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The community that relies on 3D Slicer is large and active: (numbers below updated on December 1st, 2023)

  • 2,147+ papers on PubMed citing the Slicer platform paper
    • Fedorov A., Beichel R., Kalpathy-Cramer J., Finet J., Fillion-Robin J-C., Pujol S., Bauer C., Jennings D., Fennessy F.M., Sonka M., Buatti J., Aylward S.R., Miller J.V., Pieper S., Kikinis R. 3D Slicer as an Image Computing Platform for the Quantitative Imaging Network. Magnetic Resonance Imaging. 2012 Nov;30(9):1323-41. PMID: 22770690. PMCID: PMC3466397.


The following is a sample of the research performed using 3D Slicer outside of the group that develops it. in 2022

We monitor PubMed and related databases to update these lists, but if you know of other research related to the Slicer community that should be included here please email: marianna (at) bwh.harvard.edu.

Contents

2022

Myosteatosis Is Not Associated with Complications or Survival in HCC Patients Undergoing Trans Arterial Embolization

Publication: J Clin Med. 2022 Dec 29;12(1):262. PMID: 36615062 | PDF

Authors: Masetti C, Pugliese N, Lofino L, Colapietro F, Ceriani R, Lleo A, Poretti D, Pedicini V, De Nicola S, Torzilli G, Rimassa L, Aghemo A, Lanza E.

Institution: Division of Internal Medicine and Hepatology, Department of Gastroenterology, IRCCS Humanitas Research Hospital, Milan, Italy.

Abstract: Alterations in nutritional status, in particular sarcopenia, have been extensively associated with a poor prognosis in cirrhotic patients regardless of the etiology of liver disease. Less is known about the predictive value of myosteatosis, defined as pathological fat infiltration into the skeletal muscle. We retrospectively analyzed a cohort of 151 cirrhotic patients with unresectable hepatocellular carcinoma (HCC) who underwent their first trans-arterial embolization (TAE) between 1 March 2011 and 1 July 2019 at our Institution. Clinical and biochemical data were collected. Sarcopenia was assessed using the L3-SMI method while myosteatosis with a dedicated segmentation suite (3D Slicer), using a single slice at an axial plane located at L3 and calculating the IMAC (Intramuscular Adipose Tissue Content Index). The sex-specific cut-off values for defining myosteatosis were IMAC > -0.44 in males and >-0.31 in females. In our cohort, 115 (76%) patients were included in the myosteatosis group; 128 (85%) patients had a coexistent diagnosis of sarcopenia. Patients with myosteatosis were significantly older and showed higher BMI than patients without myosteatosis. In addition, male gender and alcoholic- or metabolic-related cirrhosis were most represented in the myosteatosis group. Myosteatosis was not associated with a different HCC burden, length of hospitalization, complication rate, and readmission in the first 30 days after discharge. Overall survival was not influenced by the presence of myosteatosis.

Open-Source Image Analysis Tool for the Identification and Quantification of Cortical Interruptions and Bone Erosions in High-Resolution Peripheral Quantitative Computed Tomography Images of Patients With Rheumatoid Arthritis

Publication: Bone. 2022 Dec;165:116571. PMID: 36174928 | PDF

Authors: Zhao M, Tse JJ, Kuczynski MT, Brunet SC, Yan R, Engelke K, Peters M, van den Bergh JP, van Rietbergen B, Stok KS, Barnabe C, Pauchard Y, Manske SL.

Institution: Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Canada.

Abstract: Identification of bone erosions and quantification of erosion volume is important for rheumatoid arthritis diagnosis, and can add important information to evaluate disease progression and treatment effects. High-resolution peripheral quantitative computed tomography (HR-pQCT) is well suited for this purpose, however analysis methods are not widely available. The purpose of this study was to develop an open-source software tool for the identification and quantification of bone erosions using images acquired by HR-pQCT. The collection of modules, Bone Analysis Modules (BAM) - Erosion, implements previously published erosion analysis techniques as modules in 3D Slicer, an open-source image processing and visualization tool. BAM includes a module to automatically identify cortical interruptions, from which erosions are manually selected, and a hybrid module that combines morphological and level set operations to quantify the volume of bone erosions. HR-pQCT images of the second and third metacarpophalangeal (MCP) joints were acquired in patients with RA (XtremeCT, n = 14, XtremeCTII, n = 22). The number of cortical interruptions detected by BAM-Erosion agreed strongly with the previously published cortical interruption detection algorithm for both XtremeCT (r2 = 0.85) and XtremeCTII (r2 = 0.87). Erosion volume assessment by BAM-Erosion agreed strongly (r2 = 0.95) with the Medical Image Analysis Framework. BAM-Erosion provides an open-source erosion analysis tool that produces comparable results to previously published algorithms, with improved options for visualization. The strength of the tool is that it implements multiple image processing algorithms for erosion analysis on a single, widely available, open-source platform that can accommodate future updates.

Evaluation of Scapula and Humerus Bone Change after Repair of Small- to Medium-Sized Rotator Cuff Tears: Comparison between Healing and Retear Groups Using Three-Dimensional Computed Tomography

Publication: Clin Orthop Surg. 2022 Dec;14(4):564-75. PMID: 36518931 PDF

Authors: Kim JH, Min YK, Kim DY, Kim JW.

Institution: Department of Orthopedic Surgery, Inje University Busan Paik Hospital, Inje University College of Medicine, Busan, Korea.

Abstract: Background: Rotator cuff tendon retears after rotator cuff repair cause glenohumeral joint instability, which results in changes in the glenoid and humerus head. However, limited data are available on the bone change after repair of small- to medium-sized rotator cuff tears. The aim of this study was to evaluate the difference of glenoid and humerus bone changes between healing and retear groups after repair of small- to medium-sized rotator cuff tears.

Methods: Among patients who had arthroscopic repair due to small- to medium-sized rotator cuff tears from January 2009 to January 2017, 49 patients who underwent both preoperative and postoperative (at least 3 years after surgery) shoulder computed tomography were enrolled. Using three-dimensional reconstruction program, 3D Slicer and shape analysis program (SlicerSALT), we compared the occurrence and degree of glenoid bone change, glenoid inclination change, retroversion change, and glenoid center, as well as the degree of humerus head change, between the healing and retear groups.

Results: The occurrence of glenoid bone change was significantly more common in the retear group than in the healing group (p = 0.026). The degree of bone change in the 11-1 o'clock axial plane and 10-8 o'clock, 11-7 o'clock, and 12-6 o'clock coronal plane and the degree of glenoid inclination change were significantly larger in the retear group than the healing group (p = 0.026, p = 0.026, p = 0.026, p = 0.026, and p = 0.014, respectively), but the average value of glenoid bone change in the retear group was within the range of 0.14 to 1.01 mm for each plane. The mean humeral head change was 5.69 ± 3.67 mm increase in the retear group and 1.27 ± 2.02 mm increase in the healing group. Compared with the healing group, the retear group showed statistically significantly increased humeral head change (p < 0.001).

Conclusions: There was difference in glenoid and humerus bone change between the healing and retear groups at midterm follow-up after repair of small- to medium-sized tears. However, considering the measurement bias, the difference between the two groups was within the measurement error range.


A Nomogram Based on CT Radiomics and Clinical Risk Factors for Prediction of Prognosis of Hypertensive Intracerebral Hemorrhage

Publication: Comput Intell Neurosci. 2022 Dec 7;2022:9751988. PMID: 36531926 PDF

Authors: Fang C, An X, Li K, Zhang J, Shang H, Jiao T, Zeng Q.

Institution: Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, Shandong, China.

Abstract: Purpose: To develop and validate a clinical-radiomics nomogram based on clinical risk factors and CT radiomics feature to predict hypertensive intracerebral hemorrhage (HICH) prognosis.

Methods: A total of 195 patients with HICH treated in our hospital from January 2018 to January 2022 were retrospectively enrolled and randomly divided into two cohorts for training (n = 138) and validation (n = 57) according to the ratio of 7 : 3. All CT radiomics features were extracted from intrahematomal, perihematomal, and combined intra- and perihematomal regions by using free open-source software, 3D Slicer. The least absolute shrinkage and selection operator method was used to select the optimal radiomics features, and the radiomics score (Rad-score) was calculated. The relationship between Rad-score, clinical risk factors, and the HICH prognosis was analyzed by univariate and multivariate logistic regression analyses, and the clinical-radiomics nomogram was built. The area under the receiver operating characteristic curve (AUC) and decision curve analysis (DCA) were used to evaluate the performance of the clinical-radiomics nomogram in predicting the prognosis of HICH.

Results: A total of 1702 radiomics features were extracted from the CT images of each patient for analysis. By univariate and stepwise multivariate logistic regression analyses, age, sex, RBC, serum glucose, D-dimer level, hematoma volume, and midline shift were clinical risk factors for the prognosis of HICH. Rad-score and clinical risk factors developed the clinical-radiomics nomogram. The nomogram showed the highest predictive efficiency in the training cohort (AUC = 0.95, 95% confidence interval (CI), 0.92 to 0.98) and the validation cohort (AUC = 0.90, 95% CI, 0.82 to 0.98). The calibration curve indicated that the clinical-radiomics nomogram had good calibration. DCA showed that the nomogram had high applicability in clinical practice.

Conclusions: The clinical-radiomics nomogram incorporated with the radiomics features and clinical risk factors has good potential in predicting the prognosis of HICH.

the Traction Force of the Pulled Limb in Hip Arthroscopic Surgery Is Determined by Stiffness Coefficient Which Is Significantly Related to Muscle Volume

Publication: Knee Surg Sports Traumatol Arthrosc. 2022 Dec 7. PMID: 36477348

Authors: Yin Y, Xue S, Zhang X, Yang G, Xu Y, Wang J, Huang H.

Institution: Department of Sports Medicine, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Institute of Sports Medicine of Peking University, Beijing, China.

Abstract: Purpose: To verify the relationship between muscle volume, lateral centre-edge angle (LCEA), alpha angle (AA), body mass index (BMI) and Beighton score with stiffness coefficient (SC). To analyse the difference of traction force at different physical states of hip joint capsule.

Methods: Thirty-six patients who underwent hip arthroscopy operation were included. The volumes of some related muscles were measured in MRI images by 3D Slicer. We recorded and tested differences in traction force of five joint capsule physical states, including before (State 1) and after joint capsule puncture (State 2), after the establishment of anterolateral and mid-anterior approaches (State 3) and after incision of the joint capsule through these two approaches (States 4, 5). The correlation between muscle volume, BMI, LCEA, AA and SC was verified by Spearman test. Poisson regression was used to explain confounding variables.

Results: The average force at State 1 was 531.8 N. There were significant differences in traction force between these five states (p < 0.001). There was a significant positive correlation between muscle volumes and SC (p < 0.001). BMI had no correlation with SC (n.s.). The preoperative LCEA of the affected side was correlated with SC (p = 0.043). AA and SC were not correlated (n.s.).

Conclusion: The physical states of the hip joint capsule affected traction force. Muscle volume rather than BMI is an ideal index to estimate preoperative traction force. LCEA affected traction force, whilst AA and Beighton score did not. Measuring the muscle volume can help estimate the most suitable traction force for the patient.

3D Slicer-Based Calculation of Hematoma Irregularity Index for Predicting Hematoma Expansion in Intracerebral Hemorrhage

Publication: BMC Neurol. 2022 Dec 5;22(1):452. PMID: 36471307 PDF

Authors: Cao L, Liu M, Wang M, Ding J, Mao K, Liu K, Li S.

Institution: Department of Sports Medicine, Beijing Key Laboratory of Sports Injuries, Peking University Third Hospital, Institute of Sports Medicine of Peking University, Beijing, China.

Abstract: Background: Irregular hematoma is considered as a risk sign of hematoma expansion. The aim of this study was to quantify hematoma irregularity with computed tomography based on 3D Slicer.

Methods: Patients with spontaneous intracerebral hemorrhage who underwent an initial and subsequent non-contrast computed tomography (CT) at a single medical center between January 2019 to January 2020 were retrospectively identified. The Digital Imaging and Communication in Medicine (DICOM) standard images were loaded into the 3D Slicer, and the surface area (S) and volume (V) of hematoma were calculated. The hematoma irregularity index (HII) was defined as [Formula: see text]. Logistic regression analyses and receiver operating characteristic (ROC) curve analysis were performed to assess predictive performance of HII.

Results: The enrolled patients were divided into those with hematoma enlargement (n = 36) and those without the enlargement (n = 57). HII in hematoma expansion group was 130.4 (125.1-140.0), and the index in non-enlarged hematoma group was 118.6 (113.5-122.3). There was significant difference in HII between the two groups (P < 0.01). Multivariate logistic regression analysis revealed that the HII was significantly associated with hematoma expansion before (odds ratio = 1.203, 95% confidence interval [CI], 1.115-1.298; P < 0.001) and after adjustment for age, hematoma volume, Glasgow Coma Scale score (odds ratio = 1.196, 95% CI, 1.102-1.298, P < 0.001). The area under the ROC curve was 0.86 (CI, 0.78-0.93, P < 0.01), and the best cutoff of HII for predicting hematoma growth was 123.8.

Conclusion: As a quantitative indicator of irregular hematoma, HII can be calculated using the 3D Slicer. And the HII was independently correlated with hematoma expansion.


Interrelations Between the Too-Long Anterior Calcaneal Process, Hind and Mid-tarsal Bone Volumes, Angles and Osteochondral Lesion of the Dome of the Talus: Analysis by Software Slicer of 69 CT Scan of Feet

Publication: Indian J Orthop. 2022 Nov 16;56(12):2228-36. PMID: 36507201

Authors: Lucchesi G, Bonnel F, Mainard N, Orlando N, Sacco R, Dimeglio A, Boutry N, Canavese F.

Institution: Ortopediatria Center for Education, Research and Patient Care in Paediatric Orthopedics, Bologna, Italy.

Abstract: Introduction: Although the association between Too-Long Anterior Calcaneal Process (TLACP) and osteochondral lesion of the dome of the talus (OCL) has been hypothesized, no study has investigated the interrelations between TLACP, hind and mid-tarsal volumes and angles and the development of OCL. The main goals of this work are: (1) to measure the volume of the calcaneum, talus, navicular and cuboid in subjects with and without TLACP; (2) to evaluate the angular relationships between talus, calcaneum and navicular in subjects with and without TLACP; (3) to assess whether TLACP has an effect on the volume of OCL.

Methods: This is a retrospective study of 69 CT scans of 54 consecutive children aged 11-15 years who had undergone a CT scan due to symptomatology suggestive of TLACP. The 3D Slicer software allowed to calculate the volume of the talus, calcaneum, navicular, cuboid, TLACP and OCL (in cm3). The PACS system was used to perform the angular measurements (in degrees) between talus, calcaneum and navicular in the frontal, axial and sagittal plane.

Results: Amid the 69 CT scans, 49 were found to have pathologies related to TLACP (71%, TLACP Group) and 20/69 were normal (29%, Control Group). The mean hind and mid-tarsal bone volumes of the TLACP group were comparable to those of the control group. There were 40 (81.6%) OCLs detected exclusively in pathological feet (TLACP group); 32 lesions were medial (80%), and 8 lesions were lateral (20%). According to Ferkel and Sgaglione CT Staging System, there were 22 (55%) stage 1 lesions, 5 (12.5%) stage 2A, 3 (7.5%) stage 2B and 10 (25%) stage three lesions. Only the angle between the talus and calcaneum in the frontal plane was significantly lower in pathological feet with respect to the control group (p < 0.001). In pathological feet, the talus was supinated, and the calcaneus pronated.

Conclusions: TLACP tend to stiffen the foot, modifying its biomechanics and leading to supination of the talus and pronation of the calcaneum. This induces an overpressure at the medial side of the talus where we observed a greater frequency of medial OCL with larger volume than lateral OCL.


A Novel Three-Step Process for the Identification of Inner Ear Malformation Types

Publication: Laryngoscope Investig Otolaryngol. 2022 Nov 24;7(6):2020-8. PMID: 36544941 PDF

Authors: Dhanasingh AE, Weiss NM, Erhard V, Altamimi F, Roland P, Hagr A, Van Rompaey V, Van de Heyning P.

Institution: Research and Development Department, MED-EL Innsbruck Austria.

Abstract: Objective: We hypothesize that visualizing inner-ear systematically in both cochlear view (oblique coronal plane) and in mid-modiolar section (axial plane) and following three sequential steps simplifies, identification of inner-ear malformation types.

Methods: Pre-operative computer-tomography (CT) scans of temporal bones of 112 ears with various inner ear malformation (IEM) types were taken for analysis. Images were analyzed using DICOM viewers, 3D Slicer, and OTOPLAN®. The inner-ear was captured in the oblique-coronal plane for the measurement of length and width of cochlear basal turn which is also called as A-, and B-values respectively (Step 1). In the same plane, the angular-turns of lateral-wall (LW) of cochlear basal turn were measured (Step 2). As Step 3, the mid-modiolar section of inner ear was captured in the axial plane by following the A-value and perpendicular to cochlear view. From the mid-modiolar section, the outer-contour of inner ear was captured manually by following contrasting gray area between fluid filled and bony promontory and was compared to known resembling objects to identify IEM types (Step 3).

Results: Following reference values have emerged from our analysis: A-, and B-values (Step 1) on average are >8 mm and >5.5 mm respectively, in normal cochleae (NA), enlarged vestibular aqueduct syndrome (EVAS), incomplete partition (IP) type-I and -II, whereas it is <8 mm and <5.5 mm respectively, in IP type-III and cochlear hypoplasia (CH). Angular-turn of LW is consistently observed in cochlear basal turn (Step 2), is 540° in NA and EVAS, 450° in IP-II, and 360° in IP types I & III. In subjects with CH type, angular-turn of LW is either 360° or 450° or 540°. In true mid-modiolar section, outer-contour of inner-ear (Step-3), other than in CH and cystic inner-ear malformations, resembles recognizable shapes of known objects. Absence of EVA is an additional characteristic that confirms diagnosis of CH when the A-, B-values, and angular-turn of LW can be similar to other anatomical types. Drawing a straight line along posterior edge of internal auditory canal (IAC) in axial view can differentiate a true common cavity (CC) from cochlear aplasia-vestibular cavity (VC).


Chew on This: Oral Jaw Shape Is Not Correlated With Diet Type in Loricariid Catfishes

Publication: PLoS One. 2022 Nov 2;17(11):e0277102. PMID: 36322589 | PDF

Authors: Black CR, Armbruster JW.

Institution: Department Entomology National Museum of Natural History Smithsonian Institution, Washington, District of Columbia, USA.

Abstract: The correlation between form and function is influenced by biomechanical constraints, natural selection, and ecological interactions. In many species of suction-feeding fishes, jaw shape has shown to be closely associated with diet. However, these correlations have not been tested in fishes that have more complex jaw functions. For example, the neotropical loricariid catfishes possess a ventrally facing oral disk, which allows for the oral jaws to adhere to surfaces to conduct feeding. To determine if jaw shape is correlated to diet type, we assessed oral jaw shape across 36 species using CT scans. Shape was quantified with traditional and automated landmarking in 3D Slicer, and diet type correlation was calculated using the phylogenetic generalized least squares (PGLS) method. We found that traditional and automated processes captured shape effectively when all jaw components were combined. PGLS found that diet type did not correlate to jaw shape; however, there was a correlation between clades with diverse diets and fast evolutionary rates of shape. These results suggest that shape is not constrained to diet type, and that similarly shaped jaws coupled with different types of teeth could allow the fishes to feed on a wide range of materials.

Can Quantitative Peritumoral CT Radiomics Features Predict the Prognosis of Patients With Non-Small Cell Lung Cancer? A Systematic Review

Publication: Eur Radiol. 2022 Oct 29. PMID: 36307554

Authors: Wu L, Lou X, Kong N, Xu M, Gao C.

Institution: Department of Radiology, The First Affiliated Hospital of Zhejiang Chinese Medical University (Zhejiang Provincial Hospital of Chinese Medicine), Hangzhou, China.

Abstract: Objectives: To provide an overarching evaluation of the value of peritumoral CT radiomics features for predicting the prognosis of non-small cell lung cancer and to assess the quality of the available studies.

Methods: The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for studies predicting the prognosis in patients with non-small cell lung cancer (NSCLC) using CT-based peritumoral radiomics features. Information about the patient, CT-scanner, and radiomics analyses were all extracted for the included studies. Study quality was assessed using the Radiomics Quality Score (RQS) and the Prediction Model Risk of Bias Assessment Tool (PROBAST).

Results: Thirteen studies were included with 2942 patients from 2017 to 2022. Only one study was prospective, and the others were all retrospectively designed. Manual segmentation and multicenter studies were performed by 69% and 46% of the included studies, respectively. 3D Slicer and MATLAB software were most commonly used for the segmentation of lesions and extraction of features. The peritumoral region was most frequently defined as dilated from the tumor boundary of 15 mm, 20 mm, or 30 mm. The median RQS of the studies was 13 (range 4-19), while all of included studies were assessed as having a high risk of bias (ROB) overall.

Conclusions: Peritumoral radiomics features based on CT images showed promise in predicting the prognosis of NSCLC, although well-designed studies and further biological validation are still needed.

A Custom-Made Removable Appliance for the Decompression of Odontogenic Cysts Fabricated Using a Digital Workflow

Publication: J Dent. 2022 Nov;126:104295. PMID: 36116543 | PDF

Authors: Kivovics M, Pénzes D, Moldvai J, Mijiritsky E, Németh O.

Institution: Department of Community Dentistry, Semmelweis University, Budapest, Hungary.

Abstract: This case series aimed to assess the feasibility of a custom-made decompression appliance fabricated using a digital workflow to decompress odontogenic cysts. Additionally, the treated cysts were assessed for volumetric changes.

Methods: A three-dimensional (3D) reconstruction software (CoDiagnostiX version 10.4) was used to obtain the master cast STL (Standard Tessellation Language) file by placing a customized virtual implant to create a recess for the tube of the decompression device. The decompression appliance was planned using Dental Wings Open Software (DWOS). Following rapid prototyping, the tube of the appliance was perforated using round burs. In cases where the appliances were designed to replace teeth, denture teeth were added using the conventional workflow. The appliances were delivered on the day of the cystostomy. Following decompression, cyst enucleation was performed. Cyst volume was assessed by manual segmentation of pre- and post-operative cone-beam computed tomography (CBCT) reconstructions using slice-by-slice boundary drawing with a scissors tool in the 3D Slicer v4.10.2 software. Percentage of volume reduction was calculated as follows: volume reduction/pre-operative volume × 100.

Results: Six odontogenic cysts in six patients (5 male, 1 female; age 40 years, range: 15-49 years) with a pre- and post-operative cyst volume of 5597 ± 3983 mm3 and 2330 ± 1860 mm3 respectively (p < 0.05) were treated. Percentage of volume reduction was 58.84 ± 13.22 % following a 6-month-long decompression period.

Conclusions: The digital workflow described in this case series enables the delivery of decompression appliances at the time of cystostomy, thus effectively reducing the volume of odontogenic cysts. The resulting bone formation established a safe zone around the anatomical landmarks; therefore, during enucleation surgery, complications to these landmarks can be avoided.

Associations of Depressive Symptoms With White Matter Abnormalities and Regional Cerebral Blood Flow in Patients With Amnestic Mild Cognitive Impairment

Publication: Geriatr Gerontol Int. 2022 Oct;22(10):846-850. PMID: 36058887

Authors: Hirao K, Yamashita F, Kato H, Kaneshiro K, Tsugawa A, Haime R, Fukasawa R, Sato T, Kanetaka H, Umahara T, Sakurai H, Hanyu H, Shimizu S.

Institution: Department of Geriatric Medicine, Tokyo Medical University, Tokyo, Japan.

Abstract: Aim: Depressive symptoms are one of the most common neuropsychiatric symptoms in patients with mild cognitive impairment (MCI) and Alzheimer's disease (AD), although the pathophysiologies of the depressive symptoms that occur in these diseases have not been elucidated to date. In this study, we therefore investigated the associations between depressive symptoms and cognitive performance, white matter abnormalities, and regional cerebral blood flow (rCBF) in amnestic MCI patients.

Methods: Thirty-eight patients with amnestic MCI were analyzed. The volumes of periventricular hyperintensities (PVH) and deep white matter hyperintensities (DWMH) were measured on T2-fluid-attenuated inversion recovery magnetic resonance imaging using the imaging software 3D Slicer. Associations between the Geriatric Depression Scale (GDS) score and other neuropsychological test scores on the one hand and the PVH and DWMH volumes on the other were analyzed. Voxel-wise correlations of rCBF with GDS score, after controlling for the effects of age, were investigated using SPM8 software.

Results: Significant correlations were identified between GDS score, Trail Making Test B and apathy scale scores on the one hand and PVH volume on the other. A significant negative association between GDS score and rCBF was identified in the right dominant bilateral dorsolateral prefrontal cortex (DLPFC).

Conclusions: Depressive symptoms are significantly associated with PVH volume in MCI patients. The rCBF of the DLPFC was significantly associated with depressive symptoms, suggesting that this area might be closely involved in the pathogenesis of the depressive symptoms observed in MCI patients.

Preoperative MRI for Postoperative Seizure Prediction: A Radiomics Study of Dysembryoplastic Neuroepithelial Tumor and a Systematic Review

Publication: Neurosurg Focus. 2022 Oct;53(4):E7. PMID: 36183180

Authors: Wang J, Luo X, Chen C, Deng J, Long H, Yang K, Qi S.

Institution: Department of Neurosurgery, Nanfang Hospital, Southern Medical University, Guangzhou, China.

Abstract: Objective: In this systematic review the authors aimed to evaluate the effectiveness and superiority of radiomics in detecting tiny epilepsy lesions and to conduct original research in the use of radiomics for preliminary prediction of postoperative seizures in patients with dysembryoplastic neuroepithelial tumor (DNET).

Methods: The PubMed and Web of Science databases were searched from the earliest record, January 1, 2018, to December 29, 2021, for reports of the detection of epilepsy using radiomics, and the resulting articles were carefully checked according to the PRISMA 2020 guidelines. The authors then conducted original research by evaluating MR images in 18 patients, who were then separated into two groups, the epilepsy recurrence group (ERG) and the epilepsy nonrecurrence group. The tumor region and the edema region were segmented manually by 3D Slicer. The radiomics data were extracted from MR images by using "Slicer Radiomics" running on Mac OS X. Tumor regions were observed with T1-weighted imaging, and edema with FLAIR imaging. Radiomics features with significant differences were selected through comparison according to epilepsy relapses performed with the Mann-Whitney U-test. The edema and tumor regions were also compared within groups to identify their distinctive features. Radiomics features were tested to verify their ability to predict recurrence epilepsy by receiver operating characteristic curve.

Results: This systematic review located 9 original articles related to epilepsy and radiomics published from 2018 to 2021. The reported studies demonstrated that radiomics is useful for detecting tiny epilepsy lesions. Among the radiomics features used, the predictive ability of the area under the curve was more than 0.8. The heterogeneity of the peritumoral edema region was found to be higher in the ERG.

Conclusions: Satellite lesions in the peritumoral edema region of DNET patients may cause epilepsy recurrence, and radiomics is an emerging method to detect and evaluate these epilepsy-associated lesions.

Three-Dimensional Changes in the Mandibular Proximal Segment After Using a Surgery-First Approach in Patients With Class III Malocclusion and Facial Asymmetry

Publication: J Craniofac Surg. 2022 Oct 1;33(7):1956-1961. PMID: 35175981 | PDF

Authors: Kim M, Jha N, Choi JH, Kim YJ, Lee U, Cevidanes L, Choi JY, Baek SH.

Institution: University of Ulsan Department of Oral and Maxillofacial Surgery, Chungang University Hospital, Seoul, South Korea.

Abstract: This study was performed to evaluate condylar position and angulation after asymmetric mandibular setback between a conventional (CA) and surgery-first approach (SFA) using three-dimensional analysis. The condylar positions of 30 patients with skeletal Class III malocclusion and facial asymmetry who underwent 1-jaw (sagittal split ramus osteotomy) or 2-jaw orthognathic surgery (Le Fort I osteotomy and sagittal split ramus osteotomy) with CA (n = 18) or SFA (n = 12) from 2 university hospitals were studied. The three-dimensional assessment of condylar changes was performed using computed tomography images at the initial time point (T0) and at least 6 months after surgery (T1). Segmentation of condyles and cranial base assessment from cone-beam computed tomography images were performed using ITK-SNAP software (version 3.4.0). Condylar position and angulation changes were calculated using 3D Slicer v. 4.10.2 software, and statistical analysis was performed. No significant translational or rotational condylar changes were observed between the deviated and nondeviated sides in each group or between the CA and SFA groups except yaw (P = 0.014). Linear mixed-model analysis and multivariate analysis showed no significant difference between the CA and SFA groups. Surgery-first approach might not be associated with more harmful effects on the condylar position and angulation changes as compared with CA.

A Novel Stereotactic Aspiration Technique for Intracerebral Hemorrhage

Publication: World Neurosurg. 2022 Oct 18:S1878-8750(22)01467-X. PMID: 36270590

Authors: Xu HZ, Guo J, Wang C, Liu X, Song ZQ, Chen RF, Qiu B, Wang Q, Huang Y.

Institution: Departments of Neurosurgery, Civil Aviation General Hospital, Beijing, China.

Abstract: Background: Minimally invasive surgery (MIS) is effective and recommended for the treatment of intracerebral hemorrhage (ICH), whereas neurosurgeons in grass-root hospitals in undeveloped countries are lacking in effective and precise MIS techniques. Hereby, we present the technique of CTA-based 3D-printed navigation mold-guided stereotactic aspiration and demonstrate its clinical application using a hard needle for a series of patients.

Methods: We give a detailed description of the procedure and technique used in the novel stereotactic aspiration and report on its clinical outcome in our center. Moreover, we compared the volume of hematoma measured by three different methods: ABC/2 formula, manual segmentation with Osirix and manual segmentation with 3D Slicer.

Results: The surgery was completed safely within an average operation time of 15.11 minutes, achieving the goal of < 15ml residual clot volume or >70% clot removal in all patients. No intracranial rebleeding or infection was observed postoperatively. 61.11% (11/18) of patients achieved mRS< 3 after 6 months' rehabilitation. There was overall better agreement of hematoma measurement using segmentation with 3D Slicer rather than the ABC/2 measurement, when compared with hematoma measurement using segmentation with Osirix.

Conclusions: We present a new method of stereotactic aspiration, which benefits patients in this study with good percent clot removal, few surgery-related complications, and a favorable prognosis. And manual segmentation with 3D Slicer could be used to provide neurosurgeon with solid information about hematoma volume. This cheap and convenient technique may provide a novel choice for grass-root hospitals in undeveloped countries, but it needs to be assessed in multicenter prospective clinical trials.

Characteristics of Cognitive Function in Patients With Cerebellar Infarction and Its Association With Lesion Location

Publication: Front Aging Neurosci. 2022 Oct 4;14:965022. PMID: 36268191 | PDF

Authors: Liu Q, Liu C, Zhang Y.

Institution: Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Abstract: Objective: This study aimed to explore the characteristics of cognitive function in patients with cerebellar infarction and its association with lesion location. Methods: Forty-five patients with isolated cerebellar infarction were collected in the Department of Neurology, Beijing Tiantan Hospital. Thirty healthy controls were recruited matched by age and education. Global cognitive function was evaluated by using Addenbrooke's Cognitive Examination version III (ACE-III). An extensive neuropsychological assessment battery was also tested to evaluate the characteristics of each cognitive domain. 3D Slicer software was used to draw the lesion, and evaluate the lesions' volume, side, and location. Group analysis was used to compare the differences in cognitive performance between patients and healthy controls, and patients with left and right cerebellar hemisphere infarction. Spearman analysis was used to explore the correlation between cognitive function and lesion volume. We also subdivided each patient's lesions according to the cerebellar atlas to identify the specific cerebellar location related to cognitive decline. Results: Patients with cerebellar infarction had a lower ACE-III score compared with the healthy group (87.9 ± 6.2 vs. 93.7 ± 2.9, p < 0.001), and 22 (48.9%) patients were diagnosed with cognitive impairment. The z-transformed score of attention and executive function in the patients' group was -0.9 ± 1.4 and -0.8 ± 1.0 respectively, with 19 (43.2%) and 23 (56.4%) patients impaired. Compared with healthy controls, the relative risk ratio with 95% confidence interval (CI) for impairment in attention and executive function were 3.24 (1.22-8.57) and 3.39 (1.45-7.89). However, only 10 (22.1%) patients showed impairment in more than two cognitive domains. Compared with the left lesion group, patients with right cerebellar infarction showed significantly impaired executive function (-1.1 ± 0.3 vs. -0.5 ± 0.2, p = 0.01). And the cerebellar posterior lobe regions, especially lobules VI, VIII, and IX, were explored to have lower cognitive performance. Furthermore, lesion volume was identified to be associated with the ACE-III score (r = -0.37, p = 0.04). Conclusion: We identified that cerebellar involvement in cognition, especially in attention processing and executive function. Cerebellar right-sided lateralization of cognition and functional topography were also revealed in the current study.

The Reliability of the Measurement of Muscle Volume Using Magnetic Resonance Imaging in Typically Developing Infants by Two Raters

Publication: Sci Rep. 2022 Oct 28;12(1):18191. PMID: 36307532 | PDF

Authors: Whitta G, Liang J, Stott NS, Mirjalili SA, Battin M, Williams SA.

Institution: Department of Anatomy and Medical Imaging, Faculty of Medical and Health Sciences, University of Auckland, Auckland, New Zealand.

Abstract: To assess intra-rater and inter-rater reliability of the manual segmentation of Magnetic Resonance Imaging (MRI) for the in vivo measurement of infant muscle volume of the knee extensor and flexor muscles by two raters. Muscles of the knee extensor and flexor muscle of ten typically developing infants (86 days ± 7 days) were scanned with MRI (Proton density sequence). Scans were then segmented using 3D Slicer software, and volumes rendered by two raters. Intra-rater and inter-rater reliability were assessed using intra-class correlation (ICC), with mean difference (MD), standard error of the mean (SEM), and minimal detectable change (MDC) for each muscle calculated. ICCs for Intra-rater reliability of the segmentation process for the muscle volume of the muscles of the knee extensors and flexor muscles were 0.901-0.972, and 0.776-0.945 respectively, with inter-rater reliabilities between 0.914-0.954 and 0.848-0.978, for the knee extensor and flexors muscles respectively. For intra-rater reliability, MD ≤ - 0.47 cm3, MDCs for were < 1.09 cm3 and for inter-rater MD ≤ - 1.40 cm3, MDCs for were < 1.63 cm3 for all muscles. MRI segmentation for muscle volumes showed good to excellent reliability, though given the small volumes of the muscles themselves, variations between raters are amplified. Care should be taken in the reporting and interpretation of infant muscle volume.

Minimizing MR Image Geometric Distortion at 7 Tesla for Frameless Presurgical Planning Using Skin-Adhered Fiducials

Publication: Med Phys. 2022 Oct 27. PMID: 36301228

Authors: Kirby KM, Koons EK, Welker KM, Fagan AJ.

Institution: Department of Radiology, Mayo Clinic, Rochester, MN, USA.

Abstract: Background: 7T MRI offers significant benefits to spatial and contrast resolution compared to lower field strengths. This superior image quality can help better delineate targets in stereotactic neurosurgical procedures; however, the potential for increased geometric distortions at 7T has impaired its widespread use for these applications. Image geometric distortions can be due to distortions of B0 arising from tissue magnetic susceptibility effects or inherent field inhomogeneities, and nonlinearity of the magnetic field gradients.

Purpose: The purpose of this study was to investigate the use of 7T MRI for neurosurgical frameless stereotactic navigation procedures. Image geometric distortions at the skin surface in 7T images were minimized and compared to results from clinical 3T frameless imaging protocols.

Methods: A 3D-printed grid phantom filled with oil was designed to perform a fine calibration of the 7T imaging gradients, and an oil-filled head phantom with internal targets was used to determine ground truth (from CT) positioning errors. Three volunteers and the head phantom were imaged consecutively at 3T and 7T. 10 skin-adhesive fiducial markers were placed on each subject's exposed skin surface at standard clinical placement locations for frameless procedures. Imaging sequences included MPRAGE (three bandwidths at 7T: 400, 690, and 1020 Hz/pixel, and one at 3T: 400 Hz/pixel), T2 SPACE, and T2 SPACE FLAIR acquisitions. An additional GRE fieldmap was acquired on both scanners using a multi-echo GRE sequence. Custom Matlab code was used to perform additional distortion correction of the images using the unwrapped field maps. Fiducial localization was performed with 3D Slicer , with absolute fiducial positioning errors determined in phantom experiments following rigid registration to the CT images. For human experiments, 3T and 7T images were registered and relative differences in fiducial locations were compared using two-tailed paired t-tests.

Results: Phantom measurements at 7T yielded gradient distance scaling errors of 1.1%, 2.2%, and 1.0% along the x-, y- and z-axes, respectively. These system miscalibrations were traced back to phantom manufacturing deviations in sphericity of the vendor's gradient calibration phantom. Correction factors along each gradient axis were applied, and afterward, geometric distortions of less than 1 mm were obtained in the 7T MR head phantom images for the 1020 Hz/pixel bandwidth MPRAGE sequence. For the human subjects, four fiducial locations were excluded from analysis due to patient positioning differences. Differences between 3T and 7T MPRAGE with low/medium/high bandwidth were 2.2mm / 2.6mm / 2.3mm, respectively, before the correction, reducing to 1.6mm / 1.3mm / 1.0mm after the correction (p<0.001). T2 SPACE and T2 SPACE FLAIR yielded a similar pattern when the correction was applied, decreasing from 2.1mm to 0.8mm, and 2.6mm to 1.0mm, respectively.

Conclusions: 7T MRI can be used to perform frameless presurgical planning with skin-adhesive fiducials. Geometric distortions can be reduced to a clinically relevant level (errors <∼1mm) with no significant susceptibility-related distortions, by using high receiver bandwidth, ensuring gradients are properly calibrated, and placing skin fiducials in areas where distortions from patient positioning are minimal.

Machine Learning for the Prediction of Osteopenia/Osteoporosis Using the CT Attenuation of Multiple Osseous Sites From Chest CT

Publication: Eur J Radiol. 2022 Oct;155:110474. PMID: 35988394

Authors: Sebro R, De la Garza-Ramos C.

Institution: Department of Radiology, Mayo Clinic, Jacksonville, FL, USA.

Abstract: To use machine learning and the CT attenuation of all bones visible on chest CT scans to predict osteopenia/osteoporosis.

Method: We retrospectively evaluated 364 patients with CT scans of the chest, and Dual-energy X-ray absorptiometry (DXA) scans within 6 months of each other. Studies were performed between 01/01/2015 and 08/01/2021. Volumetric segmentation of the ribs, thoracic vertebrae, sternum, and clavicle was performed using 3D Slicer to obtain the mean CT attenuation of each bone. The study sample was randomly split into training/validation (80 %, n = 291 patients) and test (20 %, n = 73 patients) datasets. Univariate analyses were used to identify the optimal CT attenuation thresholds to diagnose osteopenia/osteoporosis. We used penalized multivariable logistic regression models including Least Absolute Shrinkage and Selection Operator (LASSO), Elastic Net, and Ridge regression, and Support Vector Machines (SVM) with radial basis functions (RBF) to predict osteopenia/osteoporosis and compared these results to the CT attenuation threshold at T12.

Results: There were positive correlations between the CT attenuation between all bones (r > 0.6, P < 0.001 for all). There were positive correlations between CT attenuation of the bones and the L1-L4 BMD T-score, total hip T-score, and femoral neck T-scores (r > 0.4, P < 0.001 for all). A CT attenuation threshold of 170.2 Hounsfield units (HU) at T12 had an AUC of 0.702, while a threshold of 192.1 HU at T4 had an AUC of 0.757. The SVM with RBF had the highest AUC (AUC = 0.864) and was better than the LASSO (P = 0.011), Elastic Net (P = 0.011), Ridge regression (P = 0.011) but was not better than using the CT attenuation at T12 (P = 0.060).

Conclusions: The CT attenuation of the ribs, thoracic vertebra, sternum, and clavicle can be used individually and collectively to predict BMD and to predict osteopenia/osteoporosis.

Can Radiomic Feature Analysis Differentiate Adrenal Metastases From Lipid-Poor Adenomas on Single-Phase Contrast-Enhanced CT Abdomen?

Publication: Clin Radiol. 2022 Oct;77(10):e711-e718. PMID: 35948490

Authors: O'Shea A, Kilcoyne A, McDermott E, O'Grady M, McDermott S.

Institution: Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.

Abstract: Aim: To assess if radiomic feature analysis could help to differentiate between the lipid-poor adenomas and metastases to the adrenal glands.

Materials and methods: Eighty-six patients (women:men 42:44; mean age 66 years) with biopsy-proven adrenal metastases and 55 patients (women:men 39:16; mean age 67 years) with lipid-poor adenomas who underwent contrast-enhanced, portal-venous phase CT of the abdomen. Radiomic features were extracted using the PyRadiomics extension for 3D Slicer. Following elastic net regularisation, seven of 1,132 extracted radiomic features were selected to build a radiomic signature. This was combined with patient demographics to create a predictive nomogram. The calibration curves in both the training and validation cohorts were assessed using a Hosmer-Lemeshow test.

Results: The radiomic signature alone yielded an area under the curve of 91.7% in the training cohort (n=93) and 87.1% in the validation cohort (n=48). The predictive nomogram, which combined age, a previous history of malignancy, and the radiomic signature, had an AUC of 97.2% in the training cohort and 90.4% in the validation cohort.

Conclusion: The present nomogram has the potential to differentiate between a lipid-poor adrenal adenoma and adrenal metastasis on portal-venous CT.

Application of Machine Learning Model to Predict Osteoporosis Based on Abdominal Computed Tomography Images of the Psoas Muscle: A Retrospective Study

Publication: BMC Geriatr. 2022 Oct 13;22(1):796. PMID: 36229793 | PDF

Authors: Huang CB, Hu JS, Tan K, Zhang W, Xu TH, Yang L.

Institution: Department of Orthopaedic Surgery, The Second Affiliated Hospital and Yuying Childrens Hospital of Wenzhou Medical University, Wenzhou, China.

Abstract: Background: With rapid economic development, the world's average life expectancy is increasing, leading to the increasing prevalence of osteoporosis worldwide. However, due to the complexity and high cost of dual-energy x-ray absorptiometry (DXA) examination, DXA has not been widely used to diagnose osteoporosis. In addition, studies have shown that the psoas index measured at the third lumbar spine (L3) level is closely related to bone mineral density (BMD) and has an excellent predictive effect on osteoporosis. Therefore, this study developed a variety of machine learning (ML) models based on psoas muscle tissue at the L3 level of unenhanced abdominal computed tomography (CT) to predict osteoporosis.

Methods: Medical professionals collected the CT images and the clinical characteristics data of patients over 40 years old who underwent DXA and abdominal CT examination in the Second Affiliated Hospital of Wenzhou Medical University database from January 2017 to January 2021. Using 3D Slicer software based on horizontal CT images of the L3, the specialist delineated three layers of the region of interest (ROI) along the bilateral psoas muscle edges. The PyRadiomics package in Python was used to extract the features of ROI. Then Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) algorithm were used to reduce the dimension of the extracted features. Finally, six machine learning models, Gaussian naïve Bayes (GNB), random forest (RF), logistic regression (LR), support vector machines (SVM), Gradient boosting machine (GBM), and Extreme gradient boosting (XGBoost), were applied to train and validate these features to predict osteoporosis.

Results: A total of 172 participants met the inclusion and exclusion criteria for the study. 82 participants were enrolled in the osteoporosis group, and 90 were in the non-osteoporosis group. Moreover, the two groups had no significant differences in age, BMI, sex, smoking, drinking, hypertension, and diabetes. Besides, 826 radiomic features were obtained from unenhanced abdominal CT images of osteoporotic and non-osteoporotic patients. Five hundred fifty radiomic features were screened out of 826 by the Mann-Whitney U test. Finally, 16 significant radiomic features were obtained by the LASSO algorithm. These 16 radiomic features were incorporated into six traditional machine learning models (GBM, GNB, LR, RF, SVM, and XGB). All six machine learning models could predict osteoporosis well in the validation set, with the area under the receiver operating characteristic (AUROC) values greater than or equal to 0.8. GBM is more effective in predicting osteoporosis, whose AUROC was 0.86, sensitivity 0.70, specificity 0.92, and accuracy 0.81 in validation sets.

Conclusion: We developed six machine learning models to predict osteoporosis based on psoas muscle images of abdominal CT, and the GBM model had the best predictive performance. GBM model can better help clinicians to diagnose osteoporosis and provide timely anti-osteoporosis treatment for patients. In the future, the research team will strive to include participants from multiple institutions to conduct external validation of the ML model of this study.

Radiomics Combined With Clinical Features in Distinguishing Non-Calcifying Tuberculosis Granuloma and Lung Adenocarcinoma in Small Pulmonary Nodules

Publication: PeerJ. 2022 Oct 19;10:e14127. PMID: 36281359 | PDF

Authors: Dong Q, Wen Q, Li N, Tong J, Li Z, Bao X, Xu J, Li D.

Institution: Department of Thoracic Surgery at No. 4 Affiliated Hospital, Harbin Medical University, Harbin, China.

Abstract: Aim: To evaluate the performance of radiomics models with the combination of clinical features in distinguishing non-calcified tuberculosis granuloma (TBG) and lung adenocarcinoma (LAC) in small pulmonary nodules.

Methodology: We conducted a retrospective analysis of 280 patients with pulmonary nodules confirmed by surgical biopsy from January 2017 to December 2020. Samples were divided into LAC group (n = 143) and TBG group (n = 137). We assigned them to a training dataset (n = 196) and a testing dataset (n = 84). Clinical features including gender, age, smoking, CT appearance (size, location, spiculated sign, lobulated shape, vessel convergence, and pleural indentation) were extracted and included in the radiomics models. 3D Slicer and FAE software were used to delineate the Region of Interest (ROI) and extract clinical features. The performance of the model was evaluated by the Area Under the Receiver Operating Characteristic (ROC) Curve (AUC).

Results: Based on the model selection, clinical features gender, and age in the LAC group and TBG group showed a significant difference in both datasets (P < 0.05). CT appearance lobulated shape was also significantly different in the LAC group and TBG group (Training dataset, P = 0.034; Testing dataset, P = 0.030). AUC were 0.8344 (95% CI [0.7712-0.8872]) and 0.751 (95% CI [0.6382-0.8531]) in training and testing dataset, respectively.

Conclusion: With the capacity to detect differences between TBG and LAC based on their clinical features, radiomics models with a combined of clinical features may function as the potential non-invasive tool for distinguishing TBG and LAC in small pulmonary nodules.

Insights into Inner Ear Function and Disease Through Novel Visualization of the Ductus Reuniens, a Seminal Communication Between Hearing and Balance Mechanisms

Publication: J Assoc Res Otolaryngol. 2022 Oct;23(5):633-645. PMID: 35804276

Authors: Smith CM, Curthoys IS, Plontke SK, Menzel M, Mukherjee P, Wong C, Laitman JT.

Institution: Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.

Abstract: The sensory end-organs responsible for hearing and balance in the mammalian inner ear are connected via a small membranous duct known as the ductus reuniens (also known as the reuniting duct (DR)). The DR serves as a vital nexus linking the hearing and balance systems by providing the only endolymphatic connection between the cochlea and vestibular labyrinth. Recent studies have hypothesized new roles of the DR in inner ear function and disease, but a lack of knowledge regarding its 3D morphology and spatial configuration precludes testing of such hypotheses. We reconstructed the 3D morphology of the DR and surrounding anatomy using osmium tetroxide micro-computed tomography and digital visualizations of three human inner ear specimens. This provides a detailed, quantitative description of the DR's morphology, spatial relationships to surrounding structures, and an estimation of its orientation relative to head position. Univariate measurements of the DR, inner ear, and cranial planes were taken using the software packages 3D Slicer and Zbrush. The DR forms a narrow, curved, flattened tube varying in lumen size, shape, and wall thickness, with its middle third being the narrowest. The DR runs in a shallow bony sulcus superior to the osseous spiral lamina and adjacent to a ridge of bone that we term the "crista reuniens" oriented posteromedially within the cranium. The DR's morphology and structural configuration relative to surrounding anatomy has important implications for understanding aspects of inner ear function and disease, particularly after surgical alteration of the labyrinth and potential causative factors for Ménière's disease.

Analysis of Cochlear Parameters in Paediatric Inner Ears with Enlarged Vestibular Aqueduct and Patent Cochlea

Publication: J Pers Med. 2022 Oct 7;12(10):1666. PMID: 36294805 | PDF

Authors: Li J, Kang S, Du H, Wang S, Wang D, Liu M, Yang S.

Institution: Department of Thoracic Surgery at No. 4 Affiliated Hospital, Harbin Medical University, Harbin, China.

Abstract: Is cochlear implant (CI) electrode selection for cochleae with an enlarged vestibular aqueduct (EVA) the same as that for patent cochleae with a normal inner ear structure? Preoperative high-resolution computed tomography (HRCT) images of 247 ears were assessed retrospectively. The A-value, B-value, and H-value were measured with OTOPLAN, and Bell curves were created to show the distribution. All ears with EVA were re-evaluated using a 3D Slicer to confirm whether incomplete partition type II (IP II) existed. The Mann-Whitney U-test was applied to determine a statistically significant difference. After adjustment with the Bonferroni correction method, a p-value ≤ 0.006 was considered significant. In total, 157 ears with patent cochlea and 90 ears with EVA were assessed. Seventy (82%) of the EVA ears had an IP II malformation, and 14 (19%) of these were not detected by CT scan but were later seen through the 3D reconstruction. A significant difference was found for the A value and B value between the patent cochleae and EVA-only and between the patent cochleae and EVA with IP II. Most EVA cases had an IP II malformation. The basal turn of the cochlea may be smaller in EVA cases than in the patent cochleae. Electrode selection should be adjusted accordingly.

Location Angle of Second Mesio-Buccal Canal in Maxillary Molars of an Indian Population: An in Vivo Retrospective CBCT Evaluation and Proposal of a New Classification

Publication: PeerJ. 2022 Oct 10;10:e14234. PMID: 36248703 | PDF

Authors: Vhorkate K, Banga K, Pawar AM, Mir S, Arora S, Wahjuningrum DA, Bhardwaj A, Luke AM.

Institution: Department of Conservative Dentistry and Endodontics, Nair Hospital Dental College, Mumbai, Maharashta, India.

Abstract: Background: The current investigation was designed for predicting the location angle of second mesio-buccal root canal in permanent maxillary (first and second) molars with the aid of proposed measuring points and line using cone beam computed tomography in an Indian population.

Methods: Three-hundred and twenty-four scans of permanent maxillary (first (n = 162) and second (n = 162)) molars with mesio-buccal 2 root canals and unassociated to the current evaluation were acquired. The maxillary molars were viewed with CSI imaging software. The images were captured and were further assessed using 3D Slicer. The assessment included of measuring the distance between the main mesio-buccal and mesio-buccal 2 canal and the angle at which the MB2 it is located utilizing proposed lines joining the disto-buccal and palatal canals. The data was tabulated for the incidence of various angles where the MB2 is located and MB-MB2 distance was determined. The angles denoted were either positive; I (0.1° to 1.9°), II (2° to 4°), III (>4°) or negative I (-0.1° to -1.9°), II (-2° to -4°), III (>-4°). On the data tabulated a new Banga Vhorkate and Pawar's (BVP's) angular classification for maxillary molars was proposed.

Results: The existence of positive angle III was found in 41.35% of maxillary first molars (36 right and 31 left of 162), whereas positive angle II appeared in 41.98% of maxillary second molars (32 right and 36 left of 162). The MB1-MB2 in maxillary 1st molar is seen to be 3.12-3.31 mm and this distance in maxillary 2nd molar is 2.8-3.1 mm. The disto-buccal to palatal canal orifice mean distance was 5.06-5.22 mm in maxillary first molars and 4.9-5.8 mm in maxillary second molars.

Conclusion: Accurate diagnosis of the location of second mesio-buccal canal increases the success rate of endodontic treatment and a better prognosis. The new proposed classification may be considerably helpful in the urge to locate the mesio-buccal 2 canal.

Enhanced Visualisation of Normal Anatomy with Potential Use of Augmented Reality Superimposed on Three-Dimensional Printed Models

Publication: Micromachines (Basel). 2022 Oct 10;13(10):1701. PMID: 36296054 | PDF

Authors: Geerlings-Batt J, Tillett C, Gupta A, Sun Z.

Institution: Discipline of Medical Radiation Science, Curtin Medical School, Curtin University, Perth, Australia.

Abstract: Anatomical knowledge underpins the practice of many healthcare professions. While cadaveric specimens are generally used to demonstrate realistic anatomy, high cost, ethical considerations and limited accessibility can often impede their suitability for use as teaching tools. This study aimed to develop an alternative to traditional teaching methods; a novel teaching tool using augmented reality (AR) and three-dimensional (3D) printed models to accurately demonstrate normal ankle and foot anatomy. An open-source software, 3D Slicer was used to segment a high-resolution magnetic resonance imaging (MRI) dataset of a healthy volunteer ankle and produce virtual bone and musculature objects. Bone and musculature were segmented using seed-planting and interpolation functions, respectively. Virtual models were imported into Unity 3D, which was used to develop user interface and achieve interactability prior to export to the Microsoft HoloLens 2. Three life-size models of bony anatomy were printed in yellow polylactic acid and thermoplastic polyurethane, with another model printed in white Visijet SL Flex with a supporting base attached to its plantar aspect. Interactive user interface with functional toggle switches was developed. Object recognition did not function as intended, with adequate tracking and AR superimposition not achieved. The models accurately demonstrate bony foot and ankle anatomy in relation to the associated musculature. Although segmentation outcomes were sufficient, the process was highly time consuming, with effective object recognition tools relatively inaccessible. This may limit the reproducibility of augmented reality learning tools on a larger scale. Research is required to determine the extent to which this tool accurately demonstrates anatomy and ascertain whether use of this tool improves learning outcomes and is effective for teaching anatomy.

Whole Tumor Radiomics Analysis for Risk Factors Associated with Rapid Growth of Vestibular Schwannoma in Contrast-Enhanced T1-Weighted Images

Publication: 2022 Oct;166:e572-e582. PMID: 35863640

Authors: Itoyama T, Nakaura T, Hamasaki T, Takezaki T, Uentani H, Hirai T, Mukasa A.

Institution: Departments of Neurosurgery Kumamoto University Hospital, Kumamoto, Japan.

Abstract: Objective: To investigate the features associated with rapid growth of vestibular schwannoma using radiomics analysis on magnetic resonance imaging (MRI) together with clinical factors.

Methods: From August 2005 to February 2019, 67 patients with vestibular schwannoma underwent contrast-enhanced T1-weighted MRI at least twice as part of their diagnosis. After excluding three cases with an extremely short follow-up period of 15 days or less, 64 patients were finally enrolled in this study. Ninety-three texture features were extracted from the tumor image data using 3D Slicer software. We determined the texture features that significantly affected maximal tumor diameter growth of more than 2 mm/year using Random Forest and Bounty. We also analyzed age and tumor size as clinical factors. We calculated the areas under the curve (AUCs) using receiver-operating characteristic analysis for prediction models using texture, clinical, and mixed factors by Random Forest and 5-fold cross-validation.

Results: Two texture features, low minimum signal and high Idmn, were significantly associated with rapid growth of vestibular schwannoma. The mixed model of texture features and clinical factors offered the highest AUC (0.69), followed by the pure texture- (0.67), and pure clinical (0.63) models. The minimum signal was the most important variable followed by tumor size, Idmn, and age.

Conclusions: Our radiomics analysis found that texture features were significantly associated with the rapid growth of vestibular schwannoma in contrast-enhanced T1-weighted images. The mixed model offered a higher diagnostic performance than the pure texture or clinical models.

A Machine Learning-Based Predictive Model of Epidermal Growth Factor Mutations in Lung Adenocarcinomas

Publication: Cancers (Basel). 2022 Sep 25;14(19):4664. PMID: 36230590 | PDF

Authors: He R, Yang X, Li T, He Y, Xie X, Chen Q, Zhang Z, Cheng T.

Institution: School of Nuclear Science and Technology, University of South China, Hengyang, China.

Abstract: Data from 758 patients with lung adenocarcinoma were retrospectively collected. All patients had undergone computed tomography imaging and EGFR gene testing. Radiomic features were extracted using the medical imaging tool 3D Slicer and were combined with the clinical features to build a machine learning prediction model. The high-dimensional feature set was screened for optimal feature subsets using principal component analysis (PCA) and the least absolute shrinkage and selection operator (LASSO). Model prediction of EGFR mutation status in the validation group was evaluated using multiple classifiers. We showed that six clinical features and 622 radiomic features were initially collected. Thirty-one radiomic features with non-zero correlation coefficients were obtained by LASSO regression, and 24 features correlated with label values were obtained by PCA. The shared radiomic features determined by these two methods were selected and combined with the clinical features of the respective patient to form a subset of features related to EGFR mutations. The full dataset was partitioned into training and test sets at a ratio of 7:3 using 10-fold cross-validation. The area under the curve (AUC) of the four classifiers with cross-validations was: (1) K-nearest neighbor (AUCmean = 0.83, Acc = 81%); (2) random forest (AUCmean = 0.91, Acc = 83%); (3) LGBM (AUCmean = 0.94, Acc = 88%); and (4) support vector machine (AUCmean = 0.79, Acc = 83%). In summary, the subset of radiographic and clinical features selected by feature engineering effectively predicted the EGFR mutation status of this NSCLC patient cohort.

Clinical and Radiomic Factors for Predicting Invasiveness in Pulmonary Ground‑Glass Opacity

Publication: Exp Ther Med. 2022 Sep 22;24(5):685. PMID: 36277144 | PDF

Authors: Dang Y, Wang R, Qian K, Lu J, Zhang Y.

Institution: Department of Thoracic Surgery, Xuanwu Hospital, Capital Medical University, Beijing, China.

Abstract: Objectives: To provide an overarching evaluation of the value of peritumoral CT radiomics features for predicting the prognosis of non-small cell lung cancer and to assess the quality of the available studies.

Methods: The PubMed, Embase, Web of Science, and Cochrane Library databases were searched for studies predicting the prognosis in patients with non-small cell lung cancer (NSCLC) using CT-based peritumoral radiomics features. Information about the patient, CT-scanner, and radiomics analyses were all extracted for the included studies. Study quality was assessed using the Radiomics Quality Score (RQS) and the Prediction Model Risk of Bias Assessment Tool (PROBAST).

Results: Thirteen studies were included with 2942 patients from 2017 to 2022. Only one study was prospective, and the others were all retrospectively designed. Manual segmentation and multicenter studies were performed by 69% and 46% of the included studies, respectively. 3D Slicer and MATLAB software were most commonly used for the segmentation of lesions and extraction of features. The peritumoral region was most frequently defined as dilated from the tumor boundary of 15 mm, 20 mm, or 30 mm. The median RQS of the studies was 13 (range 4-19), while all of included studies were assessed as having a high risk of bias (ROB) overall.

Conclusions: Peritumoral radiomics features based on CT images showed promise in predicting the prognosis of NSCLC, although well-designed studies and further biological validation are still needed.

Myosteatosis Is Not Associated with Complications or Survival in HCC Patients Undergoing Trans Arterial Embolization

Publication: OTA Int. 2022 Sep 21;5(4):e213. PMID: 36569106 | PDF

Authors: Chai Y, Simic R, Smith PN, Valter K, Limaye A, Li RW.

Institution: Trauma and Orthopaedic Research Laboratory, Department of Surgery, The Medical School, The Australian National University, Canberra, ACT, Australia.

Abstract: Objectives: Although 3-dimensional (3D) printing is becoming more widely adopted for clinical applications, it is yet to be accepted as part of standard practice. One of the key applications of this technology is orthopaedic surgical planning for urgent trauma cases. Anatomically accurate replicas of patients' fracture models can be produced to guide intervention. These high-quality models facilitate the design and printing of patient-specific implants and surgical devices. Therefore, a fast and accurate workflow will help orthopaedic surgeons to generate high-quality 3D printable models of complex fractures. Currently, there is a lack of access to an uncomplicated and inexpensive workflow. Methods: Using patient DICOM data sets (n = 13), we devised a novel, simple, open-source, and rapid modeling process using Drishti software and compared its efficacy and data storage with the 3D Slicer image computing platform. We imported the computed tomography image directory acquired from patients into the software to isolate the model of bone surface from surrounding soft tissue using the minimum functions. One pelvic fracture case was further integrated into the customized implant design practice to demonstrate the compatibility of the 3D models generated from Drishti. Results: The data sizes of the generated 3D models and the processing files that represent the original DICOM of Drishti are on average 27% and 12% smaller than that of 3D Slicer, respectively (both P < 0.05). The time frame needed to reach the stage of viewing the 3D bone model and the exporting of the data of Drishti is 39% and 38% faster than that of 3D Slicer, respectively (both P < 0.05). We also constructed a virtual model using third-party software to trial the implant design. Conclusions: Drishti is more suitable for urgent trauma cases that require fast and efficient 3D bone reconstruction with less hardware requirement. 3D Slicer performs better at quantitative preoperative planning and multilayer segmentation. Both software platforms are compatible with third-party programs used to produce customized implants that could be useful for surgical training.


The Value of Whole-Lesion Histogram Analysis Based on Field‑of‑View Optimized and Constrained Undistorted Single Shot (FOCUS) DWI for Predicting Axillary Lymph Node Status in Early-Stage Breast Cancer

Publication: BMC Med Imaging. 2022 Sep 10;22(1):163. PMID: 36088299 | PDF

Authors: Fang S, Zhu J, Wang Y, Zhou J, Wang G, Xu W, Zhang W.

Institution: Department of Radiology, Changzhou Hospital of Traditional Chinese Medicine, Changzhou, Jiangsu Province, China.

Abstract: Background: This study aims to estimate the amount of axillary lymph node (ALN) involvement in early-stage breast cancer utilizing a field of view (FOV) optimized and constrained undistorted single-shot (FOCUS) diffusion-weighted imaging (DWI) approach, as well as a whole-lesion histogram analysis.

Methods: This retrospective analysis involved 81 individuals with invasive breast cancer. The patients were divided into three groups: N0 (negative ALN metastasis), N1-2 (low metastatic burden with 1-2 ALNs), and N≥3 (heavy metastatic burden with ≥ 3 ALNs) based on their sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND). Histogram parameters of apparent diffusion coefficient (ADC) depending basically on FOCUS DWI were performed using 3D Slicer software for whole lesions. The typical histogram characteristics for N0, N1-2, and N≥ 3 were compared to identify the significantly different parameters. To determine the diagnostic efficacy of significantly different factors, the area under their receiver operating characteristic (ROC) curves was examined.

Results: There were significant differences in the energy, maximum, 90 percentile, range, and lesion size among N0, N1-2, and N≥ 3 groups (P < 0.05). The energy differed significantly between N0 and N1-2 groups (P < 0.05), and some certain ADC histogram parameters and lesion sizes differed significantly between N0 and N≥3, or N1-2 and N≥3 groups. For ROC analysis, the energy yielded the best diagnostic performance in distinguishing N0 and N1-2 groups from N≥3 group with an AUC value of0.853. All parameters revealed excellent inter-observer agreement with inter-reader consistencies data ranging from0.919 to 0.982.

Conclusion: By employing FOCUS DWI method, the analysis of whole-lesion ADC histogram quantitatively provides a non-invasive way to evaluate the degree of ALN metastatic spread in early-stage breast cancer.

Radiomics-Based Infarct Features on CT Predict Hemorrhagic Transformation in Patients With Acute Ischemic Stroke

Publication: Front Neurosci. 2022 Sep 21;16:1002717. PMID: 36213752 | PDF

Authors: Xie G, Li T, Ren Y, Wang D, Tang W, Li J, Li K.

Institution: North Sichuan Medical College, Nanchong, China.

Abstract: Objective: To develop and validate a model based on the radiomics features of the infarct areas on non-contrast-enhanced CT to predict hemorrhagic transformation (HT) in acute ischemic stroke.

Materials and methods: A total of 118 patients diagnosed with acute ischemic stroke in two centers from January 2019 to February 2022 were included. The radiomics features of infarcted areas on non-contrast-enhanced CT were extracted using 3D Slicer. A univariate analysis and the least absolute shrinkage and selection operator (LASSO) were used to select features, and the radiomics score (Rad-score) was then constructed. The predictive model of HT was constructed by analyzing the Rad-score and clinical and imaging features in the training cohort, and it was verified in the validation cohort. The model was evaluated with the receiver operating characteristic curve, calibration curve and decision curve, and the prediction performance of the model in different scenarios was further discussed hierarchically.

Results: Of the 118 patients, 52 developed HT, including 21 cases of hemorrhagic infarct (HI) and 31 cases of parenchymal hematoma (PH). The Rad-score was constructed from five radiomics features and was the only independent predictor for HT. The predictive model was constructed from the Rad-score. The area under the curve (AUCs) of the model for predicting HT in the training and validation cohorts were 0.845 and 0.750, respectively. Calibration curve and decision curve analyses showed that the model performed well. Further analysis found that the model predicted HT for different infarct sizes or treatment methods in the training and validation cohorts with 78.3 and 71.4% accuracy, respectively. For all samples, the model predicted an AUC of 0.754 for HT in patients within 4.5 h since stroke onset, and predicted an AUC of 0.648 for PH.

Conclusion: This model, which was based on CT radiomics features, could help to predict HT in the setting of acute ischemic stroke for any infarct size and provide guiding suggestions for clinical treatment and prognosis evaluation.

Prediction of Changes in Tumor Regression during Radiotherapy for Nasopharyngeal Carcinoma by Using the Computed Tomography-Based Radiomics

Publication: Contrast Media Mol Imaging. 2022 Sep 23;2022:3417480. PMID: 36226269 | PDF

Authors: Yang Y, Wu J, Mai W, Li H.

Institution: Medical Imaging Center, The First Affliated Hospital of Jinan University, Guangzhou, China.

Abstract: This work aimed to explore the application value of computed tomography (CT)-based radiomics in predicting changes in tumor regression during radiotherapy for nasopharyngeal carcinoma. In this work, 144 patients with nasopharyngeal carcinoma who underwent concurrent chemoradiotherapy (CCRT) in our hospital from January 2015 to December 2021 were selected. The patients were divided into a radiosensitive group (79 cases) and an insensitive group (65 cases) according to the tumor volume shrinkage during radiotherapy. The 3D Slicer v.4.10.2 software was used to delineate the tumor region of interest (ROI), and a total of 1223 radiomics features were extracted using the radiomics module under the software. After between-group and within-group consistency tests, one-way ANOVA, and LASSO dimensionality reduction, three omics features were finally selected for the establishment of predictive models. At the same time, the age, gender, tumor T stage and N stage, hemoglobin, and albumin of the patients were collected to establish a clinical prediction model. The results showed that compared with logistic regression, decision tree, random forest, and AdaBoost models, the SVM model based on CT radiomics features had the best performance in predicting tumor regression changes during tumor radiotherapy (training group area under the receiver operating characteristic curve (AUC): 0.840 (95% confidence interval (CI): 0.764-0.916); validation group: AUC: 0.810 (95% CI: 0.676-0.944)). Compared with the supported vector machine (SVM) prediction model based on clinical features, the SVM model based on radiomics features had better performance in predicting the change of retraction during tumor radiotherapy (training group: omics feature SVM model AUC: 0.84, clinical feature SVM model: 0.78; validation group: omics feature SVM model AUC: 0.8, clinical feature SVM model: 0.58, P = 0.044). Based on the radiomics characteristics and clinical characteristics of patients, a nomo prediction map was established, and the calibration curve shows good consistency, which can be visualized to assist clinical judgment. In this work, the prediction model composed of CT-based radiomic features combined with clinical features can accurately predict withdrawal changes during tumor radiotherapy, ensuring the accuracy of treatment planning, and minimizing the number of CT scans during radiotherapy.

3D Printed Model to Assist Endovascular Prostate Artery Embolization for Benign Prostatic Hyperplasia

Publication: Radiol Case Rep. 2022 Sep 6;17(11):4161-4164. PMID: 36105833 | PDF

Authors: Dalla S, Richards L, Alli A, Custer B, Rohr A.

Institution: University of Kansas School of Medicine, Kansas City, KS, USA.

Abstract: With the growth and ease of 3D printing accessibility, the medical community has begun to adopt it in various ways. Modeling of prostatic arteries for embolization is an application that has yet to be fully explored. We present a case where a patient specific 3D-printed model was used as a reference during prostate artery embolization for a 70-year-old male with obstructive benign prostatic hyperplasia refractory to medical treatment. The prostate arteries were segmented from preoperative contrast enhanced computed tomography using 3D Slicer software and printed on a FormLabs Form2 resin printer. The models were then used for operative planning for the embolization of both right and left prostate arteries. The procedure was a success without complications and the patient returned 1 month later with significantly improved symptoms. Additionally, interventionists found the model to be helpful in selecting approach for arterial embolization.

Gastroenteropancreatic Neuroendocrine Neoplasms (GEP-NENs): A Radiomic Model to Predict Tumor Grade

Publication: Radiol Med. 2022 Sep;127(9):928-938. PMID: 35917099

Authors: Chiti G, Grazzini G, Flammia F, Matteuzzi B, Tortoli P, Bettarini S, Pasqualini E, Granata V, Busoni S, Messserini L, Pradella S, Massi D, Miele V.

Institution: Department of Emergency Radiology, University Hospital Careggi, Florence, Italy.

Abstract: Purpose: The aim of this single-center retrospective study is to assess whether contrast-enhanced computed tomography (CECT) radiomics analysis is predictive of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) grade based on the 2019 World Health Organization (WHO) classification and to establish a tumor grade (G) prediction model.

Material and methods: Preoperative CECT images of 78 patients with GEP-NENs were retrospectively reviewed and divided in two groups (G1-G2 in class 0, G3-NEC in class 1). A total of 107 radiomics features were extracted from each neoplasm ROI in CT arterial and venous phases acquisitions with 3D Slicer. Mann-Whitney test and LASSO regression method were performed in R for feature selection and feature reduction, in order to build the radiomic-based predictive model. The model was developed for a training cohort (75% of the total) and validated on the independent validation cohort (25%). ROC curves and AUC values were generated on training and validation cohorts.

Results: 40 and 24 features, for arterial phase and venous phase, respectively, were found to be significant in class distinction. From the LASSO regression 3 and 2 features, for arterial phase and venous phase, respectively, were identified as suitable for groups classification and used to build the tumor grade radiomic-based prediction model. The prediction of the arterial model resulted in AUC values of 0.84 (95% CI 0.72-0.97) and 0.82 (95% CI 0.62-1) for the training cohort and validation cohort, respectively, while the prediction of the venous model yielded AUC values of 0.7877 (95% CI 0.6416-0.9338) and 0.6813 (95% CI 0.3933-0.9693) for the training cohort and validation cohort, respectively.

Conclusions: CT-radiomics analysis may aid in differentiating the histological grade for GEP-NENs.

Planning System for the Optimization of Electric Field Delivery Using Implanted Electrodes for Brain Tumor Control

Publication: Med Phys. 2022 Sep;49(9):6055-6067. PMID: 35754362

Authors: Iredale E, Voigt B, Rankin A, Kim KW, Chen JZ, Schmid S, Hebb MO, Peters TM, Wong E.

Institution: Department of Medical Biophysics, Schulich School of Medicine and Dentistry, Western University, London, Ontario, Canada.

Abstract: Background: The use of non-ionizing electric fields from low-intensity voltage sources (< 10 V) to control malignant tumor growth is showing increasing potential as a cancer treatment modality. A method of applying these low-intensity electric fields using multiple implanted electrodes within or adjacent to tumor volumes has been termed as intratumoral modulation therapy (IMT).

Purpose: This study explores advancements in the previously established IMT optimization algorithm, and the development of a custom treatment planning system for patient-specific IMT. The practicality of the treatment planning system is demonstrated by implementing the full optimization pipeline on a brain phantom with robotic electrode implantation, postoperative imaging, and treatment stimulation.

Methods: The integrated planning pipeline in 3D Slicer begins with importing and segmenting patient magnetic resonance images (MRI) or computed tomography (CT) images. The segmentation process is manual, followed by a semi-automatic smoothing step that allows the segmented brain and tumor mesh volumes to be smoothed and simplified by applying selected filters. Electrode trajectories are planned manually on the patient MRI or CT by selecting insertion and tip coordinates for a chosen number of electrodes. The electrode tip positions and stimulation parameters (phase shift and voltage) can then be optimized with the custom semi-automatic IMT optimization algorithm where users can select the prescription electric field, voltage amplitude limit, tissue electrical properties, nearby organs at risk, optimization parameters (electrode tip location, individual contact phase shift and voltage), desired field coverage percent, and field conformity optimization. Tables of optimization results are displayed, and the resulting electric field is visualized as a field-map superimposed on the MR or CT image, with 3D renderings of the brain, tumor, and electrodes. Optimized electrode coordinates are transferred to robotic electrode implantation software to enable planning and subsequent implantation of the electrodes at the desired trajectories.

Results: An IMT treatment planning system was developed that incorporates patient-specific MRI or CT, segmentation, volume smoothing, electrode trajectory planning, electrode tip location and stimulation parameter optimization, and results visualization. All previous manual pipeline steps operating on diverse software platforms were coalesced into a single semi-automated 3D Slicer-based user interface. Brain phantom validation of the full system implementation was successful in preoperative planning, robotic electrode implantation, and postoperative treatment planning to adjust stimulation parameters based on actual implant locations. Voltage measurements were obtained in the brain phantom to determine the electrical parameters of the phantom and validate the simulated electric field distribution.

Conclusions: A custom treatment planning and implantation system for IMT has been developed in this study and validated on a phantom brain model, providing an essential step in advancing IMT technology toward future clinical safety and efficacy investigations.

Diagnostic Value of 18F-FDG PET/CT-Based Radiomics Nomogram in Bone Marrow Involvement of Pediatric Neuroblastoma

Publication: Acad Radiol. 2022 Sep 15:S1076-6332(22)00476-7. PMID: 36117128

Authors: Feng L, Yang X, Lu X, Kan Y, Wang C, Zhang H, Wang W, Yang J.

Institution: Department of Nuclear Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Abstract: Objectives: To develop and validate an 18F-FDG PET/CT-based radiomics nomogram and evaluate the value of the 18F-FDG PET/CT-based radiomics nomogram for the diagnosis of bone marrow involvement (BMI) in pediatric neuroblastoma.

Materials and methods: A total of 144 patients with neuroblastoma (100 in the training cohort and 44 in the validation cohort) were retrospectively included. The PET/CT images of patients were visually assessed. The results of bone marrow aspirates or biopsies were used as the gold standard for BMI. Radiomics features and conventional PET parameters were extracted using the 3D Slicer. Features were selected by the least absolute shrinkage and selection operator regression, and radiomics signature was constructed. Univariate and multivariate logistic regression analyses were applied to identify the independent clinical risk factors and construct the clinical model. Other different models, including the conventional PET model, combined PET-clinical model and combined radiomics model, were built using logistic regression. The combined radiomics model was based on clinical factors, conventional PET parameters and radiomics signature, which was presented as a radiomics nomogram. The diagnostic performance of the different models was evaluated by receiver operating characteristic (ROC) curves and decision curve analysis (DCA).

Results: By visual assessment, BMI was observed in 80 patients. Four conventional PET parameters (SUVmax, SUVmean, metabolic tumor volume, and total lesion glycolysis) were extracted. And 15 radiomics features were selected to build the radiomics signature. The 11q aberration, neuron-specific enolase and vanillylmandelic acid were identified as the independent clinical risk factors to establish the clinical model. The radiomics nomogram incorporating the radiomics signature, the independent clinical risk factors and SUVmean demonstrated the best diagnostic value for identifying BMI, with an area under the curve (AUC) of 0.963 and 0.931 in the training and validation cohorts, respectively. And the DCA demonstrated that the radiomics nomogram was clinically useful.

Conclusion: The 18F-FDG PET/CT-based radiomics nomogram which incorporates radiomics signature, independent clinical risk factors and conventional PET parameters could improve the diagnostic performance for BMI of pediatric neuroblastoma without additional medical costs and radiation exposure.

Radiomics Nomogram: Prediction of 2-Year Disease-Free Survival in Young Age Breast Cancer

Publication: Cancers (Basel). 2022 Sep 14;14(18):4461. PMID: 36139620 | PDF

Authors: Lee J, Kim SH, Kim Y, Park J, Park GE, Kang BJ.

Institution: Department of Radiology, College of Medicine, Seoul Saint Mary's Hospital, The Catholic University of Korea, Seoul, Korea.

Abstract: This study aimed to predict early breast cancer recurrence in women under 40 years of age using radiomics signature and clinicopathological information. We retrospectively investigated 155 patients under 40 years of age with invasive breast cancer who underwent MRI and surgery. Through stratified random sampling, 111 patients were assigned as the training set, and 44 were assigned as the validation set. Recurrence-associated factors were investigated based on recurrence within 5 years during the total follow-up period. A Rad-score was generated through texture analysis 3D Slicer, v.4.8.0) of breast MRI using the least absolute shrinkage and selection operator Cox regression model. The Rad-score showed a significant association with disease-free survival (DFS) in the training set (p = 0.003) and validation set (p = 0.020) in the Kaplan-Meier analysis. The nomogram was generated through Cox proportional hazards models, and its predictive ability was validated. The nomogram included the Rad-score and estrogen receptor negativity as predictive factors and showed fair DFS predictive ability in both the training and validation sets (C-index 0.63, 95% CI 0.45-0.79). In conclusion, the Rad-score can predict the disease recurrence of invasive breast cancer in women under 40 years of age, and the Rad-score-based nomogram showed reasonably high DFS predictive ability, especially within 2 years of surgery.

Clinical-Radiomics Nomogram for Identifying HER2 Status in Patients With Breast Cancer: A Multicenter Study

Publication: Front Oncol. 2022 Sep 7;12:922185. PMID: 36158700 | PDF

Authors: Fang C, Zhang J, Li J, Shang H, Li K, Jiao T, Yin D, Li F, Cui Y, Zeng Q.

Institution: Department of Radiology, Shandong Provincial Qianfoshan Hospital, The First Hospital Affiliated Hospital of Shandong First Medical University, Jinan, China.

Abstract: Purpose: To develop and validate a clinical-radiomics nomogram based on radiomics features and clinical risk factors for identification of human epidermal growth factor receptor 2 (HER2) status in patients with breast cancer (BC).

Methods: Two hundred and thirty-five female patients with BC were enrolled from July 2018 to February 2022 and divided into a training group (from center I, 115 patients), internal validation group (from center I, 49 patients), and external validation group (from centers II and III, 71 patients). The preoperative MRI of all patients was obtained, and radiomics features were extracted by a free open-source software called 3D Slicer. The Least Absolute Shrinkage and Selection Operator regression model was used to identify the most useful features. The radiomics score (Rad-score) was calculated by using the radiomics signature-based formula. A clinical-radiomics nomogram combining clinical factors and Rad-score was developed through multivariate logistic regression analysis. The performance of the nomogram was evaluated using receiver operating characteristic (ROC) curve and decision curve analysis (DCA).

Results: A total of 2,553 radiomics features were extracted, and 21 radiomics features were selected as the most useful radiomics features. Multivariate logistic regression analysis indicated that Rad-score, progesterone receptor (PR), and Ki-67 were independent parameters to distinguish HER2 status. The clinical-radiomics nomogram, which comprised Rad-score, PR, and Ki-67, showed a favorable classification capability, with AUC of 0.87 [95% confidence internal (CI), 0.80 to 0.93] in the training group, 0.81 (95% CI, 0.69 to 0.94) in the internal validation group, and 0.84 (95% CI, 0.75 to 0.93) in the external validation group. DCA illustrated that the nomogram was useful in clinical practice.

Conclusions: The nomogram combined with Rad-score, PR, and Ki-67 can identify the HER2 status of BC.

Volumetric Pancreas Segmentation on Computed Tomography: Accuracy and Efficiency of a Convolutional Neural Network Versus Manual Segmentation in 3D Slicer in the Context of Interreader Variability of Expert Radiologists

Publication: J Comput Assist Tomogr. 2022 Sep 1. PMID: 36055122

Authors: Khasawneh H, Patra A, Rajamohan N, Suman G, Klug J, Majumder S, Chari ST, Korfiatis P, Goenka AH.

Institution: From the Department of Radiology, Mayo Clinic, Rochester, MN, USA.

Abstract: Purpose: This study aimed to compare accuracy and efficiency of a convolutional neural network (CNN)-enhanced workflow for pancreas segmentation versus radiologists in the context of interreader reliability.

Methods: Volumetric pancreas segmentations on a data set of 294 portal venous computed tomographies were performed by 3 radiologists (R1, R2, and R3) and by a CNN. Convolutional neural network segmentations were reviewed and, if needed, corrected ("corrected CNN [c-CNN]" segmentations) by radiologists. Ground truth was obtained from radiologists' manual segmentations using simultaneous truth and performance level estimation algorithm. Interreader reliability and model's accuracy were evaluated with Dice-Sorenson coefficient (DSC) and Jaccard coefficient (JC). Equivalence was determined using a two 1-sided test. Convolutional neural network segmentations below the 25th percentile DSC were reviewed to evaluate segmentation errors. Time for manual segmentation and c-CNN was compared.

Results: Pancreas volumes from 3 sets of segmentations (manual, CNN, and c-CNN) were noninferior to simultaneous truth and performance level estimation-derived volumes [76.6 cm3 (20.2 cm3), P < 0.05]. Interreader reliability was high (mean [SD] DSC between R2-R1, 0.87 [0.04]; R3-R1, 0.90 [0.05]; R2-R3, 0.87 [0.04]). Convolutional neural network segmentations were highly accurate (DSC, 0.88 [0.05]; JC, 0.79 [0.07]) and required minimal-to-no corrections (c-CNN: DSC, 0.89 [0.04]; JC, 0.81 [0.06]; equivalence, P < 0.05). Undersegmentation (n = 47 [64%]) was common in the 73 CNN segmentations below 25th percentile DSC, but there were no major errors. Total inference time (minutes) for CNN was 1.2 (0.3). Average time (minutes) taken by radiologists for c-CNN (0.6 [0.97]) was substantially lower compared with manual segmentation (3.37 [1.47]; savings of 77.9%-87% [P < 0.0001]).

Conclusions: Convolutional neural network-enhanced workflow provides high accuracy and efficiency for volumetric pancreas segmentation on computed tomography.

Stereotactic Navigation Using Registration Based on Intra-Abdominal Landmarks in Robotic-Assisted Lateral Pelvic Lymph Node Dissection

Publication: Tech Coloproctol. 2022 Sep;26(9):735-43. PMID: 35676544

Authors: Ochiai K, Kobayashi E, Sasaki K, Nozawa H, Kawai K, Murono K, Sakuma I, Ishihara S.

Institution: Department of Surgical Oncology, Faculty of Medicine, The University of Tokyo, Tokyo, Japan.

Abstract: Background: We carried out robot-assisted lateral pelvic lymph node dissection (LPLND) for rectal cancer with a stereotactic navigation system. The purpose of this study was to evaluate the accuracy and feasibility of the system.

Methods: We constructed a navigation system based on the Polaris Spectra optical tracking device (Northern Digital Inc., Canada) and the open-source software 3D Slicer v.3.8.1. We used the landmark-based registration method for patient-to-image registration. Body surface landmarks and intra-abdominal landmarks were used. We evaluated the time required for registration and target registration error (TRE; the distance between corresponding points after registration) for the root of the superior gluteal artery the root of the obturator or superior vesical artery, and the obturator foramen during minimally invasive LPLND for rectal cancer. Five patients who had LPLND for rectal cancer at the University of Tokyo Hospital between September 2020 and May 2021 were enrolled.

Results: The mean time required for registration was 49 s with the body surface landmarks and 88 s with the intra-abdominal landmarks. The mean TRE improved markedly when the registration was performed using intra-abdominal landmarks. The mean TRE of the root of the superior gluteal artery, the root of the obturator or superior vesical artery, and the obturator foramen were 55.8 mm, 53.4 mm, and 55.2 mm with the body surface landmarks and 11.8 mm, 10.0 mm, and 12.6 mm with the intra-abdominal landmarks, respectively. There were no adverse events related to the registration process.

Conclusions: When stereotactic navigation systems are used for minimally invasive LPLND, the use of intra-abdominal landmarks for registration is feasible and may allow simpler and more accurate navigation than the use of body surface landmarks.

Utilizing 3D Slicer to Incorporate Tomographic Images Into GATE Monte Carlo Simulation for Personalized Dosimetry in Yttrium-90 Radioembolization

Publication: Med Phys. 2022 Sep 13. PMID: 36098271

Authors: Abdul Hadi MFR, Abdullah AN, Hashikin NAA, Ying CK, Yeong CH, Yoon TL, Ng KH.

Institution: School of Physics, Universiti Sains Malaysia, USM, Penang, Malaysia.

Abstract: Purpose: Monte Carlo (MC) simulation is an important technique that can help design advanced and challenging experimental setups. GATE (Geant4 application for tomographic emission) is a useful simulation toolkit for applications in nuclear medicine. Transarterial radioembolization is a treatment for liver cancer, where microspheres embedded with yttrium-90 (90 Y) are administered intra-arterially to the tumor. Personalized dosimetry for this treatment may provide higher dosimetry accuracy compared to the conventional partition model (PM) calculation. However, incorporation of three-dimensional tomographic input data into MC simulation is an intricate process. In this article, 3D Slicer, free and open-source software, was utilized for the incorporation of patient tomographic images into GATE to demonstrate the feasibility of personalized dosimetry in hepatic radioembolization with 90 Y.

Methods: In this article, the steps involved in importing, segmenting, and registering tomographic images using 3D Slicer were thoroughly described, before importing them into GATE for MC simulation. The absorbed doses estimated using GATE were then compared with that of PM. SlicerRT, a 3D Slicer extension, was then used to visualize the isodose from the MC simulation.

Results: A workflow diagram consisting of all the steps taken in the utilization of 3D Slicer for personalized dosimetry in 90 Y radioembolization has been presented in this article. In comparison to the MC simulation, the absorbed doses to the tumor and normal liver were overestimated by PM by 105.55% and 20.23%, respectively, whereas for lungs, the absorbed dose estimated by PM was underestimated by 25.32%. These values were supported by the isodose distribution obtained via SlicerRT, suggesting the presence of beta particles outside the volumes of interest. These findings demonstrate the importance of personalized dosimetry for a more accurate absorbed dose estimation compared to PM.

Conclusion: The methodology provided in this study can assist users (especially students or researchers who are new to MC simulation) in navigating intricate steps required in the importation of tomographic data for MC simulation. These steps can also be utilized for other radiation therapy related applications, not necessarily limited to internal dosimetry.

Three-Dimensional Printer Use in the Australian and New Zealand Radiation Therapy Setting

Publication: J Med Radiat Sci. 2022 Sep 12. PMID: 36097141

Authors: Albantow CE, Brown SJ.

Institution: Crown Princess Mary Cancer Centre, Westmead Hospital, Westmead, New South Wales, Australia.

Abstract: Introduction: This cross-sectional survey aimed to collect data from radiation therapy departments around Australia and New Zealand to establish a baseline of 3D printer and product use.

Methods: Each department in Australia and New Zealand was contacted to determine the most appropriate person to answer the survey. A Microsoft Forms link to the survey was sent to the individual. The survey contained 47 questions in relation to what 3D printing device departments had (if any), how it was being utilised, and what 3D printed products were in use.

Results: A total of 112 departments completed the survey (100% response rate), with 22.3% reporting 3D printer ownership, and thirty-four departments (30.4%) outsourcing 3D printed products. The primary use of 3D printers was bolus production (60.9%). Public departments represented 84% of printer ownership, while private departments were the greatest users of outsourced 3D printed products (91.4%). 3D Slicer was the most common software used for Digital Imaging and Communications in Medicine (DICOM) file conversion (42.3%), while polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) were the most common filaments in use, 46% and 14%, respectively.

Conclusion: This research established a baseline for 3D printer and product use within the Australian and New Zealand radiotherapy setting.

Development of a Novel Combined Nomogram Model Integrating Rad-Score, Age and ECOG to Predict the Survival of Patients With Hepatocellular Carcinoma Treated by Transcatheter Arterial Chemoembolization

Publication: J Gastrointest Oncol. 2022 Aug;13(4):1889-1897. PMID: 36092317 | PDF

Authors: Liu A, Liu B, Duan X, Yang B, Wang Y, Dong P, Zhou P.

Institution: Department of Radiology, The Affiliated Hospital of Southwest Medical University, Luzhou, China.

Abstract: Background: Liver cancer is affecting more and more people's health. Transcatheter arterial chemoembolization (TACE) has become a routine treatment option, but the prognosis of patients is not optimistic. Effectively prediction of prognosis can provide clinicians with an objective basis for patient prognosis and timely adjustment of treatment strategies, thus improving the quality of patient survival. However, the current prediction methods have some limitations. Therefore, this study aims to develop a radiomics nomogram for predicting survival after TACE in patients with advanced hepatocellular carcinoma (HCC).

Methods: Seventy advanced HCC patients treated with TACE were enrolled from January 2013 to July 2019. Clinical information included age, sex, and Eastern Cooperative Oncology Group (ECOG) score. Overall survival (OS) was confirmed by postoperative follow-up. Radiomics features were extracted using 3D Slicer v. 4.11. software, then obtain radiomics signature and calculate radiomics score (Rad-score) for each patient. Univariate and multivariate Cox regression were used to analyze the baseline clinical data of patients and establish clinical models. The obtained radiomics signature was incorporated into the clinical model to establish the radiomics nomogram. The predictive performance and calibration ability of the model were assessed by the area under the receiver operating characteristic (ROC) curve (AUC), C-index, and calibration curve.

Results: Three significant features were selected from 851 radiomics features by the least absolute shrinkage and selection operator (LASSO) Cox regression model to construct the radiomics signature, and were significantly correlated with overall survival (P<0.001). Rad-score, age, and ECOG score were combined to construct a radiomics nomogram. The AUC, sensitivity, and specificity of the radiomics nomogram were 0.801 (95% CI: 0.693-0.909), 0.822 (95% CI: 0.674-0.915), and 0.720 (95% CI: 0.674-0.915), respectively. The C-index of the radiomics nomogram was 0.700 (95% CI: 0.547-0.853). Calibration curves showed better agreement between the predicted and actual probabilities in the radiomics nomogram among the 3 features.

Conclusions: The Rad-score was a strong risk predictor of survival after TACE for HCC patients. The radiomics nomogram might be improved the predictive efficacy of survival after TACE and it may also provide assistance to physicians in making treatment decisions.

Testing the Applicability and Performance of Auto ML for Potential Applications in Diagnostic Neuroradiology

Publication: Sci Rep. 2022 Aug 11;12(1):13648. PMID: 35953588 | PDF

Authors: Musigmann M, Akkurt BH, Krähling H, Nacul NG, Remonda L, Sartoretti T, Henssen D, Brokinkel B, Stummer W, Heindel W, Mannil M.

Institution: University Clinic for Radiology, Westfälische Wilhelms-University Muenster and University Hospital Münster, Muenster, Germany.

Abstract: To investigate the applicability and performance of automated machine learning (AutoML) for potential applications in diagnostic neuroradiology. In the medical sector, there is a rapidly growing demand for machine learning methods, but only a limited number of corresponding experts. The comparatively simple handling of AutoML should enable even non-experts to develop adequate machine learning models with manageable effort. We aim to investigate the feasibility as well as the advantages and disadvantages of developing AutoML models compared to developing conventional machine learning models. We discuss the results in relation to a concrete example of a medical prediction application. In this retrospective IRB-approved study, a cohort of 107 patients who underwent gross total meningioma resection and a second cohort of 31 patients who underwent subtotal resection were included. Image segmentation of the contrast enhancing parts of the tumor was performed semi-automatically using the open-source software platform 3D Slicer A total of 107 radiomic features were extracted by hand-delineated regions of interest from the pre-treatment MRI images of each patient. Within the AutoML approach, 20 different machine learning algorithms were trained and tested simultaneously. For comparison, a neural network and different conventional machine learning algorithms were trained and tested. With respect to the exemplary medical prediction application used in this study to evaluate the performance of Auto ML, namely the pre-treatment prediction of the achievable resection status of meningioma, AutoML achieved remarkable performance nearly equivalent to that of a feed-forward neural network with a single hidden layer. However, in the clinical case study considered here, logistic regression outperformed the AutoML algorithm. Using independent test data, we observed the following classification results (AutoML/neural network/logistic regression): mean area under the curve = 0.849/0.879/0.900, mean accuracy = 0.821/0.839/0.881, mean kappa = 0.465/0.491/0.644, mean sensitivity = 0.578/0.577/0.692 and mean specificity = 0.891/0.914/0.936. The results obtained with AutoML are therefore very promising. However, the AutoML models in our study did not yet show the corresponding performance of the best models obtained with conventional machine learning methods. While AutoML may facilitate and simplify the task of training and testing machine learning algorithms as applied in the field of neuroradiology and medical imaging, a considerable amount of expert knowledge may still be needed to develop models with the highest possible discriminatory power for diagnostic neuroradiology.

Radiomics for Pseudoprogression Prediction in High Grade Gliomas: Added Value of MR Contrast Agent

Publication: Heliyon. 2022 Aug 2;8(8):e10023. PMID: 35965975 | PDF

Authors: Mammadov O, Akkurt BH, Musigmann M, Ari AP, Blömer DA, Kasap DNG, Henssen DJHA, Nacul NG, Sartoretti E, Sartoretti T, Backhaus P, Thomas C, Stummer W, Heindel W, Mannil M.

Institution: University Clinic for Radiology, Westfälische Wilhelms-University Muenster and University Hospital Münster, Muenster, Germany.

Abstract: Objective: Our aim is to define the capabilities of radiomics in predicting pseudoprogression from pre-treatment MR images in patients diagnosed with high-grade gliomas using T1 non-contrast-enhanced and contrast-enhanced images.

Material & methods: In this retrospective IRB-approved study, image segmentation of high-grade gliomas was semi-automatically performed using 3D Slicer. Non-contrast-enhanced T1-weighted images and contrast-enhanced T1-weighted images were used prior to surgical therapy or radio-chemotherapy. Imaging data was split into a training sample and an independent test sample at random. We extracted 107 radiomic features by use of PyRadiomics. Feature selection and model construction were performed using Generalized Boosted Regression Models (GBM).

Results: Our cohort included 124 patients (female: n = 53), diagnosed with progressive (n = 61) and pseudoprogressive disease (n = 63) of primary high-grade gliomas. Based on non-contrast-enhanced T1-weighted images of the independent test sample, the mean area under the curve (AUC), mean sensitivity, mean specificity and mean accuracy of our model were 0.651 [0.576, 0.761], 0.616 [0.417, 0.833], 0.578 [0.417, 0.750] and 0.597 [0.500, 0.708] to predict the development of pseudoprogression. In comparison, the independent test data of contrast-enhanced T1-weighted images yielded significantly higher values of AUC = 0.819 [0.760, 0.872], sensitivity = 0.817 [0.750, 0.833], specificity = 0.723 [0.583, 0.833] and accuracy = 0.770 [0.687, 0.833].

Conclusion: Our findings show that it is possible to predict pseudoprogression of high-grade gliomas with a Radiomics model using contrast-enhanced T1-weighted images with comparatively good discriminatory power. The use of a contrast agent results in a clear added value.

Morphological Evaluation of the Normal and Hydrocephalic Third Ventricle on Cranial Magnetic Resonance Imaging in Children: A Retrospective Study

Publication: Pediatr Radiol. 2022 Aug 22. PMID: 35994062

Authors: Isıklar S, Turan Ozdemir S, Ozkaya G, Ozpar R, Parlak M.

Institution: Medical Imaging Techniques Program, Vocational School of Health Services, Bursa Uludag University, Bursa, Turkey.

Abstract: Background: Third ventricle morphological changes reflect changes in the ventricular system in pediatric hydrocephalus, so visual inspection of the third ventricle shape is standard practice. However, normal pediatric reference data are not available.

Objective: To investigate both the normal development of the third ventricle in the 0-18-year age group and changes in its biometry due to hydrocephalus.

Materials and methods: For this retrospective study, we selected individuals ages 0-18 years who had magnetic resonance imaging (MRI) from 2012 to 2020. We included 700 children (331 girls) who had three-dimensional (3-D) T1-weighted sequences without and 25 with hydrocephalus (11 girls). We measured the distances between the anatomical structures limiting the third ventricle by dividing the third ventricle into anterior and posterior regions. We made seven linear measurements and three index calculations using 3D Slicer and MRICloud pipeline, and we analyzed the results of 23 age groups in normal and hydrocephalic patients using SPSS (v. 23).

Results: Salient findings are: (1) The posterior part of the third ventricle is more affected by both developmental and hydrocephalus-related changes. (2) For third ventricle measurements, gender was insignificant while age was significant. (3) Normal third ventricular volumetric development showed a segmental increase in the 0-18 age range. The hydrocephalic third ventricle volume cut-off value in this age group was 3 cm3.

Conclusion: This study describes third ventricle morphometry using a linear measurement method. The ratios defined in the midsagittal plane were clinically useful for diagnosing the hydrocephalic third ventricle. The linear and volumetric reference data and ratios are expected to help increase diagnostic accuracy in distinguishing normal and hydrocephalic third ventricles.

Assessing Preoperative Risk of STR in Skull Meningiomas Using MR Radiomics and Machine Learning

Publication: Sci Rep. 2022 Aug 18;12(1):14043. PMID: 35982218 | PDF

Authors: Musigmann M, Akkurt BH, Krähling H, Brokinkel B, Henssen DJHA, Sartoretti T, Nacul NG, Stummer W, Heindel W, Mannil M.

Institution: University Clinic for Radiology, Westfälische Wilhelms-University Muenster and University Hospital Muenster, Muenster, Germany.

Abstract: Our aim is to predict possible gross total and subtotal resections of skull meningiomas from pre-treatment T1 post contrast MR-images using radiomics and machine learning in a representative patient cohort. We analyse the accuracy of our model predictions depending on the tumor location within the skull and the postoperative tumor volume. In this retrospective, IRB-approved study, image segmentation of the contrast enhancing parts of the tumor was semi-automatically performed using the 3D Slicer open-source software platform. Imaging data were split into training data and independent test data at random. We extracted a total of 107 radiomic features by hand-delineated regions of interest on T1 post contrast MR images. Feature preselection and model construction were performed with eight different machine learning algorithms. Each model was estimated 100 times on new training data and then tested on a previously unknown, independent test data set to avoid possible overfitting. Our cohort included 138 patients. A gross total resection of the meningioma was performed in 107 cases and a subtotal resection in the remaining 31 cases. Using the training data, the mean area under the curve (AUC), mean accuracy, mean kappa, mean sensitivity and mean specificity were 0.901, 0.875, 0.629, 0.675 and 0.933 respectively. We obtained very similar results with the independent test data: mean AUC = 0.900, mean accuracy = 0.881, mean kappa = 0.644, mean sensitivity = 0.692 and mean specificity = 0.936. Thus, our model exposes good and stable predictive performance with both training and test data. Our radiomics approach shows that with machine learning algorithms and comparatively few explanatory factors such as the location of the tumor within the skull as well as its shape, it is possible to make accurate predictions about whether a meningioma can be completely resected by surgery. Complete resections and resections with larger postoperative tumor volumes can be predicted with very high accuracy. However, cases with very small postoperative tumor volumes are comparatively difficult to predict correctly.

Long-Term Three-Dimensional Condylar Remodeling During Presurgical Orthodontics and After Orthognathic Surgery of Mandibular Retrognathia With High Mandibular Plane Angle

Publication: Clin Oral Investig. 2022 Aug 17. PMID: 35978222

Authors: Al-Rezami KF, Abotaleb BM, Alkebsi K, Wang R, Al-Nasri A, Sakran K, Aladimi M, Yang P.

Institution: State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.

Abstract: Objectives: Patients with high mandibular plane facial morphology are the most dominant facial type who experience TMJ abnormalities with resultant condylar resorption, affecting the orthodontic and orthognathic treatment outcomes. The study aimed to quantitatively assess the three-dimensional condylar remodeling during the presurgical orthodontics and after orthognathic surgery of the retrognathic mandible with a high mandibular plane angle. The study also investigated the correlation between the resultant remodeling based on the hypothesis that condylar resorption following orthognathic surgery is a part of a progressive presurgical resorption process.

Materials and methods: The study included adults with mandibular retrognathism and high mandibular plane angle who have computed tomography scans (CT) obtained before any treatment (T0), after completion of presurgical treatment before surgery (T1), and at long-term follow-up after surgery (T2). DICOM of CT scan was gathered and processed using ITK-SNAP and 3D Slicer software. The interval between T0 and T1 was represented as a presurgical phase, while between T1 and T2 was defined as a postsurgical phase (T1-T2).

Results: Twenty-five patients (50 condyles) were included with a mean age of 23 ± 3.2 years. The mean of the follow-up during the presurgical phase was 19.8 ± 7.1 months and 15.5 ± 5.5 months during the postsurgical phase. The condylar volume during the presurgical phase (T0-T1) was relatively stable (- 3.3 ± 37.2mm3). However, during the postsurgical phase (T1-T2), the volume was significantly reduced - 113.8 ± 98.3mm3 (P < 0.001). Localized condylar surface resorption during the postsurgical phase was significantly higher than during the presurgical phase (P < 0.05). No correlation was found between the localized condylar surface remodeling during the presurgical and postsurgical phases. However, a negative statistically significant correlation existed between the overall condylar volume changes during the presurgical and postsurgical phases (r = 0.502, P < 0.001).

Conclusion: Significant condylar resorption following orthognathic surgery of the retrognathic mandible with a high mandibular plane angle might occur regardless of the presurgical status of the condyle.

Clinical relevance: The study provided an evidence to be discussed with the patients and considered throughout the treatment of mandibular retrognathia with high mandibular plane angle.

Development and External Validation of a Novel Nomogram to Predict Prostate Cancer in Biopsy-Naïve Patients With PSA <10 Ng/Ml and PI-RADS v2.1 = 3 Lesions

Publication: Med. 2022 Aug 3. PMID: 35920264

Authors: Hu C, Sun J, Xu Z, Zhang Z, Zhou Q, Xu J, Chen H, Wang C, Ouyang J.

Institution: Department of Urology, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.

Abstract: Objective: To develop and externally validate a novel nomogram in biopsy-naïve patients with prostate-specific antigen (PSA) <10 ng/ml and PI-RADS v2.1 = 3 lesions.

Methods: We retrospectively collected 307 men that underwent initial biopsy from October 2015 to January 2022 in Cohort 1 (The First Affiliated Hospital of Soochow University). External cohort (Cohort 2, Kunshan Hospital) included 109 men that met our criteria from July 2016 to June 2021. By 3D Slicer Software, the volume of all lesions was divided into two subgroups (PI-RADS v2.1 = 3a and 3b). Logistic regression analysis was performed to screen for variables and construct nomogram by analyzing clinical data from Cohort 1. Receiver operating characteristics curve analysis, calibration plot and decision curve analysis (DCA) were plotted to validate the nomogram in external cohort.

Results: A total of 70 (22.8%) patients was diagnosed with prostate cancer in Institution 1. Among them, 34 (11.1%) had clinically significant prostate cancer (csPCa). Age, prostate-specific antigen density, digital rectal examination, PI-RADS v2.1 = 3 subgroups (3a and 3b) and apparent diffusion coefficient (ADC, <750 mm2 /s) were predictive factors for prostate cancer (PCa) and csPCa. High area under the curve of the nomogram was found in Cohort 1 and Cohort 2 for PCa (0.857 vs. 0.850) and for csPCa (0.896 vs. 0.893). Calibration curves showed excellent agreement between the predicted probability and actual risk for the models in internal and external validation. The DCA demonstrated net benefit of our nomogram.

Conclusion: Until now, this is the first nomogram that predicts PCa and csPCa in biopsy-naïve patients with PSA <10 ng/ml and PI-RADS v2.1 = 3 lesions. Furthermore, PI-RADS v2.1 = 3 subgroups were considered to be an independent risk factor in our model. Our nomogram may assist urologists in biopsy decision making for these so-called "double gray zone" patients.

Masotid Growth and the Configuration of Cochlear Implant Electrode Lead

Publication: Ear Nose Throat J. 2022 Jul 21:1455613221106221. PMID: 35861389

Authors: Alhabib SF, Almuhawas F, Hagr A, Alzhrani F, Hamed N, Alenzi S, Abdelsamad Y, Dhanasingh A.

Institution: King Abdullah Ear Specialist Center (KAESC), College of Medicine, ORL Department, King Saud University, Riyadh, Saudi Arabia.

Abstract: To study the changes in the coiled configuration of electrode excess lead in the mastoid cavity in the cochlear implant recipients over time.

Methods: Post-operative CT scans at two different appointments of fourteen patients with cochlear implants (CI) were retrospectively analyzed using a DICOM viewer software, 3D Slicer. Mastoid thickness (MT) was measured in the oblique coronal plane from the round window (RW) entrance to the mastoid edge and inter-cochlear distance (ICD) was measured in the axial plane at the fundus level between two ears. 3D segmentation of the entire inner ear of both sides and coiled electrode excess lead was performed to visually compare the changes in coiled configuration between the two CT scan time points.

Result: MT and ICD increased logarithmically with the patient's age, as has been measured from both the 1st and the 2nd CT scans and a weak linear correlation between MT and ICD was observed. Growth in MT and ICT measured between the time of 1st and 2nd CT scans showed a strong linear correlation. In eight cases, changes in the electrode excess lead have been observed in the 2nd CT scan, either a change in the coiling configuration of electrode excess lead or shifted laterally toward the mastoid edge. The ICD growth between the 1st and the 2nd CT scans was >2 mm in only seven cases and all of them were children. All other six cases had no observed changes in the coiled electrode lead. In addition, the mastoid growth between the 1st and the 2nd CT scan was >2.5 mm in only 4 cases.

Conclusion: Coiled configuration of electrode excess lead could change when the MT and ICD increased over time.

Bridging 3D Slicer and ROS2 for Image-Guided Robotic Interventions

Publication: Sensors (Basel). 2022 Jul 17;22(14):5336. PMID: 35891016 | PDF

Authors: Connolly L, Deguet A, Leonard S, Tokuda J, Ungi T, Krieger A, Kazanzides P, Mousavi P, Fichtinger G, Taylor RH.

Institution: Whiting School of Engineering, Johns Hopkins University, Baltimore, MD, USA.

Abstract: Developing image-guided robotic systems requires access to flexible, open-source software. For image guidance, the open-source medical imaging platform 3D Slicer is one of the most adopted tools that can be used for research and prototyping. Similarly, for robotics, the open-source middleware suite robot operating system (ROS) is the standard development framework. In the past, there have been several "ad hoc" attempts made to bridge both tools; however, they are all reliant on middleware and custom interfaces. Additionally, none of these attempts have been successful in bridging access to the full suite of tools provided by ROS or 3D Slicer. Therefore, in this paper, we present the SlicerROS2 module, which was designed for the direct use of ROS2 packages and libraries within 3D Slicer. The module was developed to enable real-time visualization of robots, accommodate different robot configurations, and facilitate data transfer in both directions (between ROS and Slicer). We demonstrate the system on multiple robots with different configurations, evaluate the system performance and discuss an image-guided robotic intervention that can be prototyped with this module. This module can serve as a starting point for clinical system development that reduces the need for custom interfaces and time-intensive platform setup.

Radiomic Cancer Hallmarks to Identify High-Risk Patients in Non-Metastatic Colon Cancer

Publication: Cancers (Basel). 2022 Jul 15;14(14):3438. PMID: 35884499 | PDF

Authors: Caruso D, Polici M, Zerunian M, Del Gaudio A, Parri E, Giallorenzi MA, De Santis D, Tarantino G, Tarallo M, Dentice di Accadia FM, Iannicelli E, Garbarino GM, Canali G, Mercantini P, Fiori E, Laghi A.

Institution: Radiology Unit, Department of Medical Surgical Sciences and Translational Medicine, Sapienza University of Rome-Sant'Andrea University Hospital, Rome, Italy.

Abstract: The study was aimed to develop a radiomic model able to identify high-risk colon cancer by analyzing pre-operative CT scans. The study population comprised 148 patients: 108 with non-metastatic colon cancer were retrospectively enrolled from January 2015 to June 2020, and 40 patients were used as the external validation cohort. The population was divided into two groups-High-risk and No-risk-following the presence of at least one high-risk clinical factor. All patients had baseline CT scans, and 3D cancer segmentation was performed on the portal phase by two expert radiologists using open-source software 3D Slicer v4.10.2. Among the 107 radiomic features extracted, stable features were selected to evaluate the inter-class correlation (ICC) (cut-off ICC > 0.8). Stable features were compared between the two groups (T-test or Mann-Whitney), and the significant features were selected for univariate and multivariate logistic regression to build a predictive radiomic model. The radiomic model was then validated with an external cohort. In total, 58/108 were classified as High-risk and 50/108 as No-risk. A total of 35 radiomic features were stable (0.81 ≤ ICC < 0.92). Among these, 28 features were significantly different between the two groups (p < 0.05), and only 9 features were selected to build the radiomic model. The radiomic model yielded an AUC of 0.73 in the internal cohort and 0.75 in the external cohort. In conclusion, the radiomic model could be seen as a performant, non-invasive imaging tool to properly stratify colon cancers with high-risk disease.

Comparison of Three 3D Segmentation Software Tools for Hip Surgical Planning

Publication: Sensors (Basel). 2022 Jul 13;22(14):5242. PMID: 35890923 | PDF

Authors: Mandolini M, Brunzini A, Facco G, Mazzoli A, Forcellese A, Gigante A.

Institution: Department of Industrial Engineering and Mathematical Sciences, Università Politecnica delle Marche, Ancona, Italy.

Abstract: In hip arthroplasty, preoperative planning is fundamental to reaching a successful surgery. Nowadays, several software tools for computed tomography (CT) image processing are available. However, research studies comparing segmentation tools for hip surgery planning for patients affected by osteoarthritic diseases or osteoporotic fractures are still lacking. The present work compares three different software from the geometric, dimensional, and usability perspectives to identify the best three-dimensional (3D) modelling tool for the reconstruction of pathological femoral heads. Syngo.via Frontier (by Siemens Healthcare) is a medical image reading and post-processing software that allows low-skilled operators to produce prototypes. Materialise (by Mimics) is a commercial medical modelling software. 3D Slicer is an open-source development platform used in medical and biomedical fields. The 3D models reconstructed starting from the in vivo CT images of the pathological femoral head are compared with the geometries obtained from the laser scan of the in vitro bony specimens. The results show that Mimics and 3D Slicer are better for dimensional and geometric accuracy in the 3D reconstruction, while syngo.via Frontier is the easiest to use in the hospital setting.

The Prognostic Value of 18 F-FDG PET/CT Intra-Tumoural Metabolic Heterogeneity in Pretreatment Neuroblastoma Patients

Publication: Cancer Imaging. 2022 Jul 5;22(1):32. PMID: 35791003 | PDF

Authors: Liu J, Si Y, Zhou Z, Yang X, Li C, Qian L, Feng LJ, Zhang M, Zhang SX, Liu J, Kan Y, Gong J, Yang J.

Institution: Department of Nuclear Medicine, Beijing Friendship Hospital, Capital Medical University, Beijing, China.

Abstract: Background: Neuroblastoma (NB) is the most common tumour in children younger than 5 years old and notable for highly heterogeneous. Our aim was to quantify the intra-tumoural metabolic heterogeneity of primary tumour lesions by using 18F-FDG PET/CT and evaluate the prognostic value of intra-tumoural metabolic heterogeneity in NB patients.

Methods: We retrospectively enrolled 38 pretreatment NB patients in our study. 18F-FDG PET/CT images were reviewed and analyzed using 3D Slicer software. The semi-quantitative metabolic parameters of primary tumour were measured, including the maximum standard uptake value (SUVmax), metabolic tumour volume (MTV), and total lesion glycolysis (TLG). The areas under the curve of cumulative SUV-volume histogram index (AUC-CSH index) was used to quantify intra-tumoural metabolic heterogeneity. The median follow-up was 21.3 months (range 3.6 - 33.4 months). The outcome endpoint was event-free survival (EFS), including progression-free survival and overall survival. Survival analysis was performed using Cox regression models and Kaplan Meier survival plots.

Results: In all 38 newly diagnosed NB patients, 2 patients died, and 17 patients experienced a relapse. The AUC-CSHtotal (r=0.630, P<0.001) showed moderate correlation with the AUC-CSH40%. In univariate analysis, chromosome 11q deletion (P=0.033), Children's Oncology Group (COG) risk grouping (P=0.009), bone marrow involvement (BMI, P=0.015), and AUC-CSHtotal (P=0.007) were associated with EFS. The AUC-CSHtotal (P=0.036) and BMI (P=0.045) remained significant in multivariate analysis. The Kaplan Meier survival analyses demonstrated that patients with higher intra-tumoural metabolic heterogeneity and BMI had worse outcomes (log-rank P=0.002).

Conclusion: The intra-tumoural metabolic heterogeneity of primary lesions in NB was an independent prognostic factor for EFS. The combined predictive effect of intra-tumoural metabolic heterogeneity and BMI provided prognostic survival information in NB patients.

Practical Methods for Segmentation and Calculation of Brain Volume and Intracranial Volume: A Guide and Comparison

Publication: Quant Imaging Med Surg. 2022 Jul;12(7):3748-61. PMID: 35782251 | PDF

Authors: Harkey T, Baker D, Hagen J, Scott H, Palys V.

Institution: Department of Neurosurgery, University of Arkansas for Medical Sciences, Little Rock, AR, USA.

Abstract: Hypothesis: Automated image registration techniques can successfully determine anatomical variation in human temporal bones with statistical shape modeling.

Background: Background: Accurate segmentation and calculation of total brain volume (BV) and intracranial volume (ICV) (further-volumetry) may serve various clinical tasks and research studies in neuroscience. Manual segmentation is extremely time consuming. There is a relative lack of published broad recommendations and comparisons of tools for automated volumetry, especially for users without expertise in computer science, for settings with limited resources, and when neuroimaging quality is suboptimal due to clinical circumstances. Our objective is to decrease the barrier to entry for research and clinical groups to perform volumetric cranial imaging analysis using free and reliable software tools.

Methods: Automated volumetry from computed tomography (CT)/magnetic resonance imaging (MRI) scans was accomplished using 3D Slicer v. 4.11.0, FreeSurfer (v. 7.1.1), and volBrain (v. 1.0) in a cohort of 39 patients with ischemic middle cerebral artery territory brain infarcts in the acute stage. Visual inspection for accuracy was also performed. Statistical analysis included coefficient of determination (R2) and Bland-Altman (B-A) plots. A multifaceted comparison between 3D Slicer, FreeSurfer, and volBrain from practical user perspective was performed to compile a list of distinguishing features.

Results: BV: FreeSurfer, 3D Slicer, and volBrain provide similar estimations when high quality T1-MRI scans with 1 mm slices (3D scans) are available, whereas 3 mm and thicker slices (2D scans) introduce a dispersion in results. ICV: the most accurate volumetry is provided by 3D Slicer using CT scans. volBrain uses T1-MRIs and also provides good results which agree with 33D Slicer. Both of these methods may be more trustworthy than T1 MRI-derived FreeSurfer calculations.

Conclusions: All three studied tools of automated intracranial and brain volumetry - 3D Slicer, FreeSurfer, and volBrain-are free, reliable, require no complex programming, but still have certain limitations and significant differences. Based on our investigation findings, the readers should be able to select the right volumetry tool and neuroimaging study, and then follow provided step-by-step instructions to accomplish specific volumetry tasks.

Statistical Shape Model of the Temporal Bone Using Segmentation Propagation

Publication: Otol Neurotol. 2022 Jul 1;43(6):e679-e687. PMID: 35761465

Authors: Ding AS, Lu A, Li Z, Galaiya D, Ishii M, Siewerdsen JH, Taylor RH, Creighton FX.

Institution: Department of Computer Science, Johns Hopkins University Whiting School of Engineering, Baltimore, MD, USA.

Abstract: Hypothesis: Automated image registration techniques can successfully determine anatomical variation in human temporal bones with statistical shape modeling.

Background: There is a lack of knowledge about inter-patient anatomical variation in the temporal bone. Statistical shape models (SSMs) provide a powerful method for quantifying variation of anatomical structures in medical images but are time-intensive to manually develop. This study presents SSMs of temporal bone anatomy using automated image-registration techniques.

Methods: Fifty-three cone-beam temporal bone CTs were included for SSM generation. The malleus, incus, stapes, bony labyrinth, and facial nerve were automatically segmented using 3D Slicer and a template-based segmentation propagation technique. Segmentations were then used to construct SSMs using MATLAB. The first three principal components of each SSM were analyzed to describe shape variation.

Results: Principal component analysis of middle and inner ear structures revealed novel modes of anatomical variation. The first three principal components for the malleus represented variability in manubrium length (mean: 4.47 mm; ±2-SDs: 4.03-5.03 mm) and rotation about its long axis (±2-SDs: -1.6° to 1.8° posteriorly). The facial nerve exhibits variability in first and second genu angles. The bony labyrinth varies in the angle between the posterior and superior canals (mean: 88.9°; ±2-SDs: 83.7°-95.7°) and cochlear orientation (±2-SDs: -4.0° to 3.0° anterolaterally).

Conclusions: SSMs of temporal bone anatomy can inform surgeons on clinically relevant inter-patient variability. Anatomical variation elucidated by these models can provide novel insight into function and pathophysiology. These models also allow further investigation of anatomical variation based on age, BMI, sex, and geographical location.

CT-Based Radiomics for Prediction of Therapeutic Response to Everolimus in Metastatic Neuroendocrine Tumors

Publication: Radiol Med. 2022 Jul;127(7):691-701. PMID: 35717429 | PDF

Authors: Caruso D, Polici M, Rinzivillo M, Zerunian M, Nacci I, Marasco M, Magi L, Tarallo M, Gargiulo S, Iannicelli E, Annibale B, Laghi A, Panzuto F.

Institution: Department of Medical Surgical Sciences and Translational Medicine, "Sapienza"-University of Rome, Sant'Andrea University Hospital, Rome, Italy.

Abstract: To test radiomic approach in patients with metastatic neuroendocrine tumors (NETs) treated with Everolimus, with the aim to predict progression-free survival (PFS) and death.

Materials and methods: Twenty-five patients with metastatic neuroendocrine tumors, 15/25 pancreatic (60%), 9/25 ileal (36%), 1/25 lung (4%), were retrospectively enrolled between August 2013 and December 2020. All patients underwent contrast-enhanced CT before starting Everolimus, histological diagnosis, tumor grading, PFS, overall survival (OS), death, and clinical data collected. Population was divided into two groups: responders (PFS ≤ 11 months) and non-responders (PFS > 11 months). 3D segmentation was performed on whole liver of naïve CT scans in arterial and venous phases, using a dedicated software, 3D Slicer v4.10.2. A total of 107 radiomic features were extracted and compared between two groups (T test or Mann-Whitney), radiomics performance assessed with receiver operating characteristic curve, Kaplan-Meyer curves used for survival analysis, univariate and multivariate logistic regression performed to predict death, and interobserver variability assessed. All significant radiomic comparisons were validated by using a synthetic external cohort. P < 0.05 is considered significant.

Results: 15/25 patients were classified as responders (median PFS 25 months and OS 29 months) and 10/25 as non-responders (median PFS 4.5 months and OS 23 months). Among radiomic parameters, Correlation and Imc1 showed significant differences between two groups (P < 0.05) with the best performance (internal cohort AUC 0.86-0.84, P < 0.0001; external cohort AUC 0.84-0.90; P < 0.0001). Correlation < 0.21 resulted correlated with death at Kaplan-Meyer analysis (P = 0.02). Univariate analysis showed three radiomic features independently correlated with death, and in multivariate analysis radiomic model showed good performance with AUC 0.87, sensitivity 100%, and specificity 66.7%. Three features achieved 0.77 ≤ ICC < 0.83 and one ICC = 0.92.

Conclusions: In patients affected by metastatic NETs eligible for Everolimus treatment, radiomics could be used as imaging biomarker able to predict PFS and death.

Smartphone Navigated Endoscopic Port Surgery of Hypertensive Basal Ganglia Hemorrhage

Publication: J Clin Neurosci. 2022 Jul;101:193-7. PMID: 35609413

Authors: Li F, Gan Z, Xu X, Zhao Y, Wang Q, Chen C, Liu H, Xiong R, Qi Z, Sun G, Zhang J, Xu B, Chen X.

Institution: Department of Neurosurgery, Chinese PLA General Hospital, Beijing, China.

Abstract: Objective: Endoscopic port surgery is a promising alternative for the surgical treatment of intracerebral hypertensive basal ganglia hemorrhage (HBGH). The precise location of hematoma is a crucial step for surgery. The authors developed a simple, low-cost navigation method using an Android smartphone for the localization of HBGH.

Methods: All patients' CT DICOM data were processed with an open-source software, 3D Slicer. The volume of hematoma, angle, and length of trajectory were calculated automatically. A smartphone running the Android system and the Compass APP was used to help insert the inner introducer. An endoscopic port system was applied to create a working channel for neuro-endoscopic hematoma evacuation.

Results: There were 27 patients enrolled in this study (mean age 56). All patients underwent successful surgical evacuation of HBGH with neuroendoscopic evacuation. The mean time taken for the surgical plan was 4 min. The total operation time from skin incision to final suture was 82.6 min. Compared with standard neuronavigation, mean error of trajectory was 5.1 mm. The mean preoperative hematoma volume was 44.8 ml. The optimal trajectory angle averaged 39.5°and the length was 71 mm. Intraoperative blood loss was about 45 ml. Post-operative hematoma volume was 2.9 ml, and the average evacuation rate was 93.6%. One week after surgery, the mean GCS score was improved from 8.2 to 13.8 (p < 0.01).

Conclusions: This simple, low-cost navigation method using 3D Slicer, an Android smartphone with the Compass APP, helps precisely insert the endoscopic working channel to the desired point, which is crucial for satisfactory evacuation of HBGH.

A Predictive Nomogram for Atypical Meningioma Based On Preoperative Magnetic Resonance Imaging and Routine Blood Tests

Publication: World Neurosurg. 2022 Jul;163:e610-e616. PMID: 35430397

Authors: Lin Y, Dai P, Lin Q, Chen J.

Institution: Dongshan County Hospital of Fujian Province, Zhangzhou, Fujian, China.

Abstract: Objective: The objective of the study was to establish a 5-year progression-free survival prediction nomogram using preoperative routine blood tests and magnetic resonance imaging to guide postoperative treatment.

Methods: Our study was a retrospective analysis of patients with atypical meningioma admitted into our facility from January 31, 2010, to January 31, 2016. We used single-factor logistic analysis to extract valuable indicators from preoperative blood test results and 3D Slicer software to extract radiomic features from magnetic resonance imaging. The radiomics score was calculated by least absolute shrinkage and selection operator logistic regression analysis. We then combined blood indicators and radiomic signatures to construct a radiomic nomogram image. The performance of the model was evaluated comprehensively using the following three aspects: recognition ability, accuracy, and clinical value.

Results: Six significant radiological features were selected through least absolute shrinkage and selection operator logistic regression analysis. The radiometric label established by these six features has satisfactory predictive performance. The area under the curve in the training group was 0.885 (95% confidence interval, 0.8037-0.9659), and the area under the curve in the validation set was 0.789 (95% confidence interval, 0.6092-0.9686). We used the combined image tags and preoperative leukocyte and neutrophil count to construct a 5-year progression-free survival prediction nomogram.

Conclusions: The analysis results of the calibration curve and the decision curve show that the nomogram constructed by combining radiomics and preoperative blood tests has a good predictive value for 5-year progression-free survival in atypical meningioma and can provide a reference for selecting postoperative treatment options.

A Hybrid Registration Method Using the Mandibular Bone Surface for Electromagnetic Navigation in Mandibular Surgery

Publication: Int J Comput Assist Radiol Surg. 2022 Jul;17(7):1343-53. PMID: 35441961

Authors:de Geer AF, van Alphen MJA, Zuur CL, Loeve AJ, van Veen RLP, Karakullukcu MB.

Institution: Verwelius 3D Lab, Department of Head and Neck Surgery and Oncology, Netherlands Cancer Institute, Antoni van Leeuwenhoek, Amsterdam, The Netherlands.

Abstract: Purpose: To utilize navigated mandibular (reconstructive) surgery, accurate registration of the preoperative CT scan with the actual patient in the operating room (OR) is required. In this phantom study, the feasibility of a noninvasive hybrid registration method is assessed. This method consists of a point registration with anatomic landmarks for initialization and a surface registration using the bare mandibular bone surface for optimization.

Methods: Three mandible phantoms with reference notches on two osteotomy planes were 3D printed. An electromagnetic tracking system in combination with 3D Slicer software was used for navigation. Different configurations, i.e., different surface point areas and number and configuration of surface points, were tested with a dentate phantom (A) in a metal-free environment. To simulate the intraoperative environment and different anatomies, the registration procedure was also performed with an OR bed using the dentate phantom and two (partially) edentulous phantoms with atypical anatomy (B and C). The accuracy of the registration was calculated using the notches on the osteotomy planes and was expressed as the target registration error (TRE). TRE values of less than 2.0 mm were considered as clinically acceptable.

Results: In all experiments, the mean TRE was less than 2.0 mm. No differences were found using different surface point areas or number or configurations of surface points. Registration accuracy in the simulated intraoperative setting was-mean (SD)-0.96 (0.22), 0.93 (0.26), and 1.50 (0.28) mm for phantom A, phantom B, and phantom C.

Conclusion: Hybrid registration is a noninvasive method that requires only a small area of the bare mandibular bone surface to obtain high accuracy in phantom setting. Future studies should test this method in clinical setting during actual surgery.

Generating Patient-Matched 3D-Printed Pedicle Screw and Laminectomy Drill Guides From Cone Beam CT Images: Studies in Ovine and Porcine Cadavers

Publication: Med Phys. 2022 Jul;49(7):4642-52. PMID: 35445429 | PDF

Authors: Kanawati A, Constantinidis A, Williams Z, O'Brien R, Reynolds T.

Institution: Westmead Hospital, Sydney, NSW, Australia.

Abstract: Background: The emergence of robotic Cone Beam Computed Tomography (CBCT) imaging systems in trauma departments has enabled 3D anatomical assessment of musculoskeletal injuries, supplementing conventional 2D fluoroscopic imaging for examination, diagnosis, and treatment planning. To date, the primary focus has been on trauma sites in the extremities.

Purpose: To determine if CBCT images can be used during the treatment planning process in spinal instrumentation and laminectomy procedures, allowing accurate 3D-printed pedicle screw and laminectomy drill guides to be generated for the cervical and thoracic spine.

Methods: The accuracy of drill guides generated from CBCT images was assessed using animal cadavers (ovine and porcine). Preoperative scans were acquired using a robotic CBCT C-arm system, the Siemens ARTIS pheno (Siemens Healthcare, GmbH, Germany). The CBCT images were imported into 3D Slicer v.4.10.2 where vertebral models and specific guides were developed and subsequently 3D-printed. In the ovine cadaver, 11 pedicle screw guides from the T1-T5 and T7-T12 vertebra and six laminectomy guides from the C2-C7 vertebra were planned and printed. In the porcine cadaver, nine pedicle screw guides from the C3-T4 vertebra were planned and printed. For the pedicle screw guides, accuracy was assessed by three observers according to pedicle breach via the Gertzbein-Robbins grading system as well as measured mean axial and sagittal screw error via postoperative CBCT and CT scans. For the laminectomies, the guides were designed to leave 1 mm of lamina. The average thickness of the lamina at the midpoint was used to assess the accuracy of the guides, measured via postoperative CBCT and CT scans from three observers. For all measurements, the intraclass correlation coefficient (ICC) was calculated to determine observer reliability.

Results: Compared with the planned screw angles for both the ovine and porcine procedures (n = 32), the mean axial and sagittal screw error measured on the postoperative CBCT scans from three observers were 3.9 ± 1.9° and 1.8 ± 0.8°, respectively. The ICC among the observes was 0.855 and 0.849 for the axial and sagittal measurements, respectively, indicating good reliability. In the ovine cadaver, directly comparing the measured axial and sagittal screw angle of the visible screws (n = 14) in the postoperative CBCT and conventional CT scans from three observers revealed an average difference 1.9 ± 1.0° in axial angle and 1.8 ± 1.0° in the sagittal angle. The average thickness of the lamina at the middle of each vertebra, as measured on-screen in the postoperative CBCT scans by three observes was 1.6 ± 0.2 mm. The ICC among observers was 0.693, indicating moderate reliability. No lamina breaches were observed in the postoperative images.

Conclusion: Here, CBCT images have been used to generate accurate 3D-printed pedicle screw and laminectomy drill guides for use in the cervical and thoracic spine. The results demonstrate sufficient precision compared with those previously reported, generated from standard preoperative CT and MRI scans, potentially expanding the treatment planning capabilities of robotic CBCT imaging systems in trauma departments and operating rooms.

Investigating Metacarpi of Hamdani Sheep via Different Measurement and Modelling Methods: A Methodological Study

Publication: Anat Histol Embryol. 2022 Jul;51(4):484-91. PMID: 35608253

Authors: Güzel BC, Koçyiğit A, Demircioğlu İ, Demiraslan Y.

Institution: Department of Anatomy, Faculty of Veterinary Medicine, Fırat University, Elazig, Turkey.

Abstract: The aim of the study was to perform the morphometric analyses on metacarpi of Hamdani sheep via different measurement methods and to compare the methods. Thus, metacarpal bones of 15 females and 15 males were used in the study. Measurements were taken from the measurement points determined on metacarpus via four methods, and their statistical analyses were performed. When both male and female metacarpal bones were examined in the De parameter in the comparison with the methods, it was observed that the four measurement methods were different from one another (p < 0.01). When DEM and DEL measurement parameters were examined in male metacarpus, the highest value was measured in ImageJ and the smallest value was measured in 3D Slicer software; however, it was found that the statistical difference was not significant when compared numerically (p > 0.05). As a result, while it was observed that the measurements made by using digital calliper measurements, photometric analysis, and 3D software were similar in some of the parameters but there was no statistically significant difference; whereas, Statistical difference was detected in some parameters.

Continuous Subcortical Monitoring of Motor Pathways During Glioma Surgery With Ultrasonic Surgical Aspirator: Technical Description in a Single Institute Experience

Publication: J Neurosurg Sci. 2022 Jun 28. PMID: 35766211

Authors: D'Elia A, Lavalle L, Bua A, Schiano DI Cola M, Ciavarro M, Esposito V.

Institution: Neurosurgery Department, IRCCS Neuromed, Pozzilli, Isernia, Italy.

Abstract: Background: Actual challenge in surgical treatment of intra-axial gliomas involving eloquent areas is maximal safe resection. Mapping and monitoring of cortical and subcortical motor functions are important tools to avoid postoperative deficits. In the present study, we present our experience with a continuous dynamic motor mapping technique pairing a traditional monopolar stimulator with a Cavitron Ultrasonic Surgical Aspirator (CUSA) to perform a continuous stimulation of the white matter avoiding removal interruption.

Methods: We describe a single center retrospective analysis of 1-year consecutive patients with intraxial tumors located adjacent to corticospinal tract and treated with surgical resection adopting "continuous dynamic mapping technique". With the support of a reconstruction software, 3D Slicer, we classified the Extent Of Resection (EOR) as Gross Total Resection (GTR) (>98%), Sub-Total Resection (STR) (from 90% to 97%), and Partial Resection (<90%). Medical Research Council (MRC) grading was adopted to evaluate neurological outcomes (from 0 to 5), assessed on 1st postoperative day, at 1 week, 1 month and 3 months.

Results: From July 2017 to July 2018, 29 patients underwent to surgical removal of intraxial tumor adjacent to motor areas, using continuous dynamic subcortical mapping. Median age was 54 years old (range 12-75 years). At preoperative MRI tractography reconstruction, mean distance between tumor and corticospinal tract was 4,4 mm (range At 1 week post-operative assessment, motor deficits were still present in 12 patients (41%). At 1 month, 10 patients (35%) had persisting deficits, which required admission to rehabilitation department. At 3 months, 4 patients (14%) had persistent motor impairment and overall 28 patients (98%) were able to walk by themselves.

Conclusions: Our early experience showed that a combination of dynamic subcortical mapping with transcranial and cortical strip MEP (Motor Evoked Potentials) monitoring is useful in tumors close to motor eloquent areas to extend surgical resection avoiding permanent consequences. However, we need for further experience to consolidate and improve this technique.

A New Method of Preoperative Assessment of Correct Electrode Array Alignment Based on Post-Operative Measurements in a Cochlear Implanted Cohort

Publication: Eur Arch Otorhinolaryngol. 2022 Jun 21. PMID: 35727414

Authors: Horvath B, Perenyi A, Molnar FA, Nagy R, Csanady M, Kiss JG, Rovo L.

Institution: Doctoral School of Clinical Medicine, University of Szeged, Szeged, Hungary.

Abstract: Purpose: During cochlear implantation surgery, a range of complications may occur such as tip fold-over. We recently developed a method to estimate the insertion orientation of the electrode array. The aim of the study was to determine the optimal angle of orientation in a cohort of cochlear implanted patients.

Methods: On eighty-five CT scans (80 uncomplicated insertions and 5 cases with tip fold-over), location of the electrode array's Insertion Guide (IG), Orientation marker (OM) and two easily identifiable landmarks (the round window (RW) and the incus short process (ISP)) were manually marked. The angle enclosed by ISP-RW line and the Cochlear™ Slim Modiolar electrode array's OM line determined the electrode array insertion angle.

Results: The average insertion angle was 45.0-47.2° ± 10.4-12° SD and was validated with 98% confidence interval. Based on the measurements obtained, patients' sex and age had no impact on the size of this angle. Although the angles of the tip fold-over cases (44.9°, 46.9°, 34.2°, 54.3°, 55.9°) fell within this average range, the further it diverted from the average it increased the likelihood for tip fold-over.

Conclusion: Electrode array insertion in the individually calculated angle relative to the visible incus short process provides a useful guide for the surgeon when aiming for the optimal angle, and potentially enhances good surgical outcomes. Our results show that factors other than the orientation angle may additionally contribute to failures in implantation when the Slim Modiolar electrode is used.

Keywords: 3D Slicer; Cochlear implant; Medical image processing; Neuro-otology surgery; Slim Modiolar.

Role of Personalized 3D Printing in Brain Protection After Decompressive Craniectomy

Publication: Zhonghua Yi Xue Za Zhi. 2022 Jun 21;102(23):1766-70. PMID: 35705481 |

Authors: Shi ZJ, Zhang H, Jiang DH, Chen SF, Zhou LW, Tan GW, Wang ZX.

Institution: Department of Neurosurgery, the First Affiliated Hospital of Xiamen University, Xiamen, China.

Abstract: Objective: To explore the application value of personalized three-dimensional (3D) printed protective cap in brain protection after decompressive craniectomy (DC). Methods: Fourty-five patients who underwent DC from January 2021 to October 2021 were selected, including 26 males and 19 females, aged 5-73 (50±13) years old. The brain CT data were imported into 3D Slicer software to rebuild the protective cap through 3D printing. The cap was worn on the head of the patient, thereby preventing secondary braindamage. The follow-up results were compared with 53 patients without protective capduring the same period. Results: There were no statistically significant differences in age, skull defect location and follow-up time between the two groups (all P>0.05).Among 45 patients, 47 brain protective caps (2 cases with bilateral skull defects) were successfully designed. The time for image post-processingand 3D printing was (21.2±6.0) min and (62.4±8.3) min, respectively. There were 6 cases of low compliance, 9 cases of moderate compliance, 32 cases of high compliance, respectively. Six cases with low conformity were redesigned and printed, 2 of 9 cases with moderate conformity were redesigned and printed, and the remaining 7 cases reached high compliance after grinding and packaging. In the current study, 45 patients with brain protective caps were followed up for 3 months, and no secondary brain injury occurred. However, among 53 patients without brain protective caps during the same period, 4 patients had secondary accidental brain compression. The incidence of injury was 7.5 %, and the difference was statistically significant (P<0.001). Conclusion: Brain protective cap designed based on cranial CT and 3D printing can be used in patients with skull defects to protect the brain tissue from secondary crush damage and has certain clinical value.

Different Lung Parenchyma Quantification Using Dissimilar Segmentation Software: A Multi-Center Study for COVID-19 Patients

Publication: Diagnostics (Basel). 2022 Jun 20;12(6):1501. PMID: 35741310 | PDF

Authors: Risoli C, Nicolò M, Colombi D, Moia M, Rapacioli F, Anselmi P, Michieletti E, Ambrosini R, Di Terlizzi M, Grazioli L, Colmo C, Di Naro A, Natale MP, Tombolesi A, Adraman A, Tuttolomondo D, Costantino C, Vetti E, Martini C.

Institution: Department of Radiological Function, "Guglielmo da Saliceto" Hospital, Piacenza, Italy.

Abstract: Background: Chest Computed Tomography (CT) imaging has played a central role in the diagnosis of interstitial pneumonia in patients affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and can be used to obtain the extent of lung involvement in COVID-19 pneumonia patients either qualitatively, via visual inspection, or quantitatively, via AI-based software. This study aims to compare the qualitative/quantitative pathological lung extension data on COVID-19 patients. Secondly, the quantitative data obtained were compared to verify their concordance since they were derived from three different lung segmentation software.

Methods: This double-center study includes a total of 120 COVID-19 patients (60 from each center) with positive reverse-transcription polymerase chain reaction (RT-PCR) who underwent a chest CT scan from November 2020 to February 2021. CT scans were analyzed retrospectively and independently in each center. Specifically, CT images were examined manually by two different and experienced radiologists for each center, providing the qualitative extent score of lung involvement, whereas the quantitative analysis was performed by one trained radiographer for each center using three different software: 3D Slicer, CT Lung Density Analysis, and CT Pulmo 3D.

Results: The agreement between radiologists for visual estimation of pneumonia at CT can be defined as good (ICC 0.79, 95% CI 0.73-0.84). The statistical tests show that 3D Slicer overestimates the measures assessed; however, ICC index returns a value of 0.92 (CI 0.90-0.94), indicating excellent reliability within the three software employed. ICC was also performed between each single software and the median of the visual score provided by the radiologists. This statistical analysis underlines that the best agreement is between 3D Slicer "LungCTAnalyzer" and the median of the visual score (0.75 with a CI 0.67-82 and with a median value of 22% of disease extension for the software and 25% for the visual values).

Conclusions: This study provides for the first time a direct comparison between the actual gold standard, which is represented by the qualitative information described by radiologists, and novel quantitative AI-based techniques, here represented by three different commonly used lung segmentation software, underlying the importance of these specific values that in the future could be implemented as consistent prognostic and clinical course parameters.

Assessment of the Accuracy of Imaging Software for 3D Rendering of the Upper Airway, Usable in Orthodontic and Craniofacial Clinical Settings

Publication: Prog Orthod. 2022 Jun 13;23(1):22. PMID: 35691961 | PDF

Authors: Lo Giudice A, Ronsivalle V, Gastaldi G, Leonardi R.

Institution: Department of General Surgery and Medical-Surgical Specialties, School of Dentistry, Unit of Orthodontics, University of Catania, Policlinico Universitario "Gaspare Rodolico - San Marco", Catania, Italy.

Abstract: Background: Several semi-automatic software are available for the three-dimensional reconstruction of the airway from DICOM files. The aim of this study was to evaluate the accuracy of the segmentation of the upper airway testing four free source and one commercially available semi-automatic software. A total of 20 cone-beam computed tomography (CBCT) were selected to perform semi-automatic segmentation of the upper airway. The software tested were Invesalius, ITK-Snap, Dolphin 3D, 3D Slicer and Seg3D. The same upper airway models were manually segmented (Mimics software) and set as the gold standard (GS) reference of the investigation. A specific 3D imaging technology was used to perform the superimposition between the upper airway model obtained with semi-automatic software and the GS model, and to perform the surface-to-surface matching analysis. The accuracy of semi-automatic segmentation was evaluated calculating the volumetric mean differences (mean bias and limits of agreement) and the percentage of matching of the upper airway models compared to the manual segmentation (GS). Qualitative assessments were performed using color-coded maps. All data were statistically analyzed for software comparisons.

Results: Statistically significant differences were found in the volumetric dimensions of the upper airway models and in the matching percentage among the tested software (p < 0.001). Invesalius was the most accurate software for 3D rendering of the upper airway (mean bias = 1.54 cm3; matching = 90.05%) followed by ITK-Snap (mean bias = - 2.52 cm3; matching = 84.44%), Seg 3D (mean bias = 3.21 cm3, matching = 87.36%), 3D Slicer (mean bias = - 4.77 cm3; matching = 82.08%) and Dolphin 3D (difference mean = - 6.06 cm3; matching = 78.26%). According to the color-coded map, the dis-matched area was mainly located at the most anterior nasal region of the airway. Volumetric data showed excellent inter-software reliability (GS vs semi-automatic software), with coefficient values ranging from 0.904 to 0.993, confirming proportional equivalence with manual segmentation.

Conclusion: Despite the excellent inter-software reliability, different semi-automatic segmentation algorithms could generate different patterns of inaccuracy error (underestimation/overestimation) of the upper airway models. Thus, is unreasonable to expect volumetric agreement among different software packages for the 3D rendering of the upper airway anatomy.

3D Printing of Subclavian Artery: Utility for Preprocedural Planning and Correlation With Subclavian Artery Percutaneous Vascular Interventions

Publication: J Invasive Cardiol. 2022 Jun;34(6):E455-E461. PMID: 35652708

Authors: Memon S, Janzer S, Friend E, Kalra S, George JC.

Institution: Pennsylvania Hospital, University of Pennsylvania Health System, Philadelphia, PA, USA.

Abstract: Background: Three-dimensional (3D) printing for subclavian artery (SA) percutaneous vascular interventions (PVI) may allow superior understanding of patient specific complex anatomy and aid with preprocedural planning.

Methods: Five patients with computed tomography angiography (CTA) of the neck who underwent SA PVI were queried retrospectively. 3D printing of aortic arch and great vessels was accomplished with 3D Slicer software and painted with acrylic paint to highlight anatomic features. The aortic arch type and implications for preprocedural planning for SA interventions including complex chronic total occlusion (CTO) lesions were determined. Comparisons were made with SA angiograms and 3D-CTA.

Results: Of the 5 patients, type I (n = 2), type II (n = 1), and type III (n = 2) aortic arches were identified. Proximal and distal reference vessel size and total lesion length were determined using a digital millimeter caliper and correlated with intraprocedural balloons and stents. In 3D-printed models (3D-PMs) of patients with SA-CTO (n = 2), cap morphology (tapered vs blunt) and distal vessel filling were visualized, permitting optimal arterial access site selection for successful cap crossing. The vertebral arteries (VAs) were also 3D printed which further allowed the ability to delineate optimal stent deployment site (proximal or distal to VA), a common dilemma that is faced intraprocedurally. The 3D-PMs also allowed preprocedural precision in stent and balloon size and length, potentially leading to procedural efficiency and cost-effectiveness.

Conclusion: 3D printing of aortic arch and great vessel anatomy for SA-PVI allows multiple procedure-related factors to be predicted in advance, translating to decrease in contrast volume, radiation time, procedure and fluoroscopic time, thereby improving procedure and cost efficiency.

The Use of Augmented Reality Navigation Technology in Combination With Endoscopic Surgery for the Treatment of an Odontogenic Cyst of the Upper Jaw: A Technical Report

Publication: Imaging Sci Dent. 2022 Jun;52(2):225-30. PMID: 35799962 | PDF

Authors: Lysenko A, Razumova A, Yaremenko A, Ivanov V, Strelkov S, Krivtsov A.

Institution: Department of Dental Surgery and Maxillofacial Surgery, First Pavlov State Medical University, Saint-Petersburg, Russia.

Abstract: Purpose: This report presents the first known use of a rigid endoscope with augmented reality technology for the removal of an odontogenic cyst that penetrated the maxillary sinus and illustrates its practical use in a patient.

Materials and methods: In the preoperative period, cone-beam computed tomography was performed in a specially designed marker holder frame, and the contours of the cyst and the nearest anatomical formations were segmented in the 3D Slicer program. During the operation, a marker was installed on the patient's head, as well as on the tip of the endoscope, which made it possible to visualize the mass and the movement of the endoscope. The surgical intervention was performed with the support of augmented reality in HoloLens glasses (Microsoft Corporation, Redmond, WA, USA).

Results: The use of this technology improved the accuracy of surgical manipulations, reduced operational risks, and shortened the time of surgery and the rehabilitation period.

Conclusion: With the help of modern technologies, a navigation system was created that helped to track the position of the endoscope in mixed reality in real time, as well as to fully visualize anatomical formations.

Comparison of Response Assessment in Veterinary Neuro-Oncology and Two Volumetric Neuroimaging Methods to Assess Therapeutic Brain Tumour Responses in Veterinary Patients

Publication: Vet Comp Oncol. 2022 Jun;20(2):404-15. PMID: 34792828

Authors: Coppola G, Morris J, Gutierrez-Quintana R, Burnside S, José-López R.

Institution: School of Veterinary Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK.

Abstract: Standardized veterinary neuroimaging response assessment methods for brain tumours are lacking. Consequently, a response assessment in veterinary neuro-oncology (RAVNO) system which uses the sum product of orthogonal lesion diameters on 1-image section with the largest tumour area, has recently been proposed. In this retrospective study, 22 pre-treatment magnetic resonance imaging (MRI) studies from 18 dogs and four cats with suspected intracranial neoplasia were compared by a single observer to 32 post-treatment MRIs using the RAVNO system and two volumetric methods based on tumour margin or area delineation with HOROS and 3D Slicer software, respectively. Intra-observer variability was low, with no statistically significant differences in agreement index between methods (mean AI ± SD, 0.91 ± 0.06 for RAVNO; 0.86 ± 0.08 for HOROS; and 0.91 ± 0.05 for 3D Slicer), indicating good reproducibility. Response assessments consisting of complete or partial responses, and stable or progressive disease, agreed in 23 out of 32 (72%) MRI evaluations using the three methods. The RAVNO system failed to identify changes in mass burden detected with volumetric methods in six cases. 3D Slicer differed from the other two methods in three cases involving cysts or necrotic tissue as it allowed for more accurate exclusion of these structures. The volumetric response assessment methods were more precise in determining changes in absolute tumour burden than RAVNO but were more time-consuming to use. Based on observed agreement between methods, low intra-observer variability and decreased time constraint, RAVNO might be a suitable response assessment method for the clinical setting.

Intracardiac MR Imaging (ICMRI) Guiding-Sheath With Amplified Expandable-Tip Imaging and MR-Tracking for Navigation and Arrhythmia Ablation Monitoring: Swine Testing at 1.5 and 3T

Publication: Magn Reson Med. 2022 Jun;87(6):2885-900. PMID: 35142398

Authors: Schmidt EJ, Olson G, Tokuda J, Alipour A, Watkins RD, Meyer EM, Elahi H, Stevenson WG, Schweitzer J, Dumoulin CL, Johnson T, Kolandaivelu A, Loew W, Halperin HR.

Institution: Medicine (Cardiology), Johns Hopkins University, Baltimore, MD, USA.

Abstract: Purpose: Develop a deflectable intracardiac MR imaging (ICMRI) guiding-sheath to accelerate imaging during MR-guided electrophysiological (EP) interventions for radiofrequency (500 kHz) ablation (RFA) of arrhythmia. Requirements include imaging at three to five times surface-coil SNR in cardiac chambers, vascular insertion, steerable-active-navigation into cardiac chambers, operation with ablation catheters, and safe levels of MR-induced heating.

Methods: ICMRI's 6 mm outer-diameter (OD) metallic-braided shaft had a 2.6 mm OD internal lumen for ablation-catheter insertion. Miniature-Baluns (MBaluns) on ICMRI's 1 m shaft reduced body-coil-induced heating. Distal section was a folded "star"-shaped imaging-coil mounted on an expandable frame, with an integrated miniature low-noise-amplifier overcoming cable losses. A handle-activated movable-shaft expanded imaging-coil to 35 mm OD for imaging within cardiac-chambers. Four MR-tracking micro-coils enabled navigation and motion-compensation, assuming a tetrahedron-shape when expanded. A second handle-lever enabled distal-tip deflection. ICMRI with a protruding deflectable EP catheter were used for MR-tracked navigation and RFA using a dedicated 3D Slicer user-interface. ICMRI was tested at 3T and 1.5T in swine to evaluate (a) heating, (b) cardiac-chamber access, (c) imaging field-of-view and SNR, and (d) intraprocedural RFA lesion monitoring.

Results: The 3T and 1.5T imaging SNR demonstrated >400% SNR boost over a 4 × 4 × 4 cm3 FOV in the heart, relative to body and spine arrays. ICMRI with MBaluns met ASTM/IEC heating limits during navigation. Tip-deflection allowed navigating ICMRI and EP catheter into atria and ventricles. Acute-lesion long-inversion-time-T1-weighted 3D-imaging (TWILITE) ablation-monitoring using ICMRI required 5:30 min, half the time needed with surface arrays alone.

Conclusion: ICMRI assisted EP-catheter navigation to difficult targets and accelerated RFA monitoring.

Three-Dimensional Condylar Displacement and Remodelling Following Correction of Asymmetric Mandibular Prognathism With Maxillary Canting

Publication: Int J Oral Maxillofac Surg. 2022 Jun;51(6):813-22. PMID: 34924271

Authors: Abotaleb BM, Bi R, Jiang N, Ye B, Bai Y, Al-Watary MQ, Zhu S.

Institution: Department of Oral and Maxillofacial Surgery, West China Hospital of Stomatology, Sichuan University, China.

Abstract: The aim of this study was to investigate the three-dimensional condylar displacement and long-term remodelling following the correction of asymmetric mandibular prognathism with maxillary canting. Thirty consecutive patients (60 condyles) with asymmetric mandibular prognathism >4 mm and occlusal canting >3 mm, treated by Le Fort I osteotomy and bilateral sagittal split ramus osteotomy, were included. Spiral computed tomography scans obtained at different periods during long-term follow-up (mean 17 ± 7.2 months) were gathered and processed using ITK-SNAP and 3D Slicer. The condyles were subjected to translational and rotational displacements immediately after the surgery (T2), which had not fully returned to the original preoperative positions at the last follow-up (T3). Condylar remodelling was observed at the last follow-up (T3), with the shorter side condyles subjected to higher surface resorption and overall condylar volume loss. The overall condylar volume on the shorter side was significantly reduced compared to the volume on the elongated side (-11.9 ± 90.6 vs -131.7 ± 138.2 mm3; P = 0.001). About 73%, 87%, 53%, and 54% of the shorter side condyles experienced resorption on the posterior, superior, medial, and lateral surfaces, respectively; in contrast, only 50% of the elongated side condyles showed resorption on the superior surface. Higher preoperative asymmetry was significantly correlated with increased postoperative condylar displacement (P < 0.05). The vertical asymmetry and the vector of condylar displacement were associated with the resultant remodelling process. It is concluded that condylar resorption of the shorter side condyle, which may affect the long-term surgical stability, has to be considered.

New Ultra-Fast Algorithm for Cochlear Implant Misalignment Detection

Publication: Eur J Radiol. 2022 Jun;151:110283. PMID: 35390602

Authors: Waldeck S, Helal R, Al-Dhamari I, Schmidt S, von Falck C, Chapot R, Brockmann M, Overhoff D.

Institution: Department of Diagnostic and Interventional Radiology and Neuroradiology, Bundeswehr Central Hospital Koblenz, Germany.

Abstract: Purpose: Postoperative imaging following cochlear implant (CI) placement is currently the only means of diagnosing proper electrode position. Manual multiplanar reconstruction (MPR) analysis of CT and CBCT is time-consuming and requires extensive training. This study aims to evaluate the rate of CI misalignment and to determine the amount of time necessary to reach a diagnosis of correct versus incorrect CI placement for readers of different experience levels, using a novel algorithm for image analysis (ACIR) compared to MPR analysis.

Method: The retrospective single centre study included 333 patients with cochlear implant surgery between May 2002 and May 2021. Postoperative CT and CBCT images were evaluated in three subgroups and the time to diagnosis was documented. Group 1: image evaluation using conventional MPR analysis; group 2: image evaluation by an experienced neuroradiologist via a novel ultra-fast algorithm; group 3: image evaluation by a young specialist via novel ultra-fast algorithm. T-test and Pearson's chi-squared test were used for inter-group comparisons.

Results: 333 patients (63.3 ± 15.9 years; 188 men) with 335 CIs were evaluated. The rate of CI misalignment diagnosed from 3D imaging was 14.3% (n = 48). MPR analysis required 255.7 ± 70.4 s per temporal bone, whereas 3D Slicer plugin reduced analysis time to 83.3 ± 7.7 s (p < 0.001) for the experienced reader and 89.6 ± 8.7 s for the young specialist (p < 0.001).

Conclusion: 3D postoperative imaging reveals high incidences of CI misalignment. Application of a novel ultra-fast algorithm significantly reduces the time for diagnosis compared to MPR analysis for readers of varying experience levels.

COVID-19 CT Scan Lung Segmentation: How We Do It

Publication: J Digit Imaging. 2022 Jun;35(3):424-31. PMID: 35091874 | PDF

Authors: Negroni D, Zagaria D, Paladini A, Falaschi Z, Arcoraci A, Barini M, Carriero A.

Institution: Department of Radiology, "Maggiore Della Carità" Hospital, AOU Maggiore Della Carità, Corso Mazzini 18, Novara, Italy.

Abstract: The National Health Systems have been severely stressed out by the COVID-19 pandemic because 14% of patients require hospitalization and oxygen support, and 5% require admission to an Intensive Care Unit (ICU). Relationship between COVID-19 prognosis and the extent of alterations on chest CT obtained by both visual and software-based quantification that expresses objective evaluations of the percentage of ventilated lung parenchyma compared to the affected one has been proven. While commercial applications for automatic medical image computing and visualization are expensive and limited in their spread, the open-source systems are characterized by not enough standardization and time-consuming troubles. We analyzed chest CT exams on 246 patients suspected of COVID-19 performed in the Emergency Department CT room. The lung parenchyma segmentation was obtained by a threshold-based method using the open-source 3D Slicer software and software tools called "Segment Editor" and "Segment Quantification." For the three main characteristics analyzed on lungs affected by COVID-19 pneumonia, a specifical densitometry value range was defined: from - 950 to - 700 HU for well-aerated parenchyma; from - 700 to - 250 HU for interstitial lung disease; from - 250 to 250 HU for parenchymal consolidation. For the well-aerated parenchyma and the interstitial alterations, the procedure was semi-automatic with low time consumption, whereas consolidations' analysis needed manual interventions by the operator. After the chest CT, 13% of the sample was admitted to intensive care, while 34% of them to the sub-intensive care. In patients moved to intensive care, the parenchyma analysis reported a higher crazy paving presentation. The quantitative analysis of the alterations affecting the lung parenchyma of patients with COVID-19 pneumonia can be performed by threshold method segmentation on 3D Slicer. The segmentation could have an important role in the quantification in different COVID-19 pneumonia presentations, allowing to help the clinician in the correct management of patients.

A Novel Method for Observing Tumor Margin in Hepatoblastoma Based on Microstructure 3D Reconstruction

Publication: Fetal Pediatr Pathol. 2022 Jun;41(3):371-380. PMID: 32969743

Authors: Liu J, Wu X, Xu C, Ma M, Zhao J, Li M, Yu Q, Hao X, Wang G, Wei B, Xia N, Dong Q.

Institution: Department of Pediatric Surgery, Affiliated Hospital of Qingdao University, Qingdao University, Qingdao, China.

Abstract: Objective: We investigated three-dimensional (3 D) reconstruction for the assessment of the tumor margin microstructure of hepatoblastoma (HB). Methods: Eleven surgical resections of childhood hepatoblastomas obtained between September 2018 and December 2019 were formalin-fixed, paraffin-embedded, serially sectioned at 4 μm, stained with hematoxylin and eosin (every 19th and 20th section stained with alpha-fetoprotein and glypican 3), and the digital images of all sections were acquired at 100× followed by image registration using the B-spline based method with modified residual complexity. Reconstruction was performed using 3D Slicer software. Results: The reconstructed orthogonal 3 D images clearly presented the internal microstructure of the tumor margin. The rendered 3 D image could be rotated at any angle. Conclusions: Microstructure 3 D reconstruction is feasible for observing the pathological structure of the HB tumor margin.

The Preoperative Evaluation Value of 3D-Slicer Program Before Microsurgical Vascular Decompression in Patients With Hemifacial Spasm

Publication: Clin Neurol Neurosurg. 2022 Jun;217:107241. PMID: 35429853

Authors: Shi H, Li Y, Wang Y, Guo W, Zhang K, Du Y, Shi H, Qian T.

Institution: Department of Neurosurgery, Hebei General Hospital, Shijiazhuang, China.

Abstract: Background: To compare the diagnostic accuracy of 3D fast imaging employing steady-state acquisition (FIESTA) combined with 3D-time-of-flight (TOF) MR angiography (MRA) sequences (FTMS) and 3D-reconstuction synthesized by 3D Slicer program in evaluation the neurovascular relationships and offending vessels preoperatively in patients with hemifacial spasm (HFS).

Methods: Clinical data of HFS patients who underwent microsurgical vascular decompression (MVD) were analyzed. All patients underwent MRA scans with FTMS and 3D-reconstruction before surgery. The neurovascular relationship and offending vessels were evaluated and compared with intraoperative findings.

Results: Forty patients were included in this study, 18 (45%) of them were male. The mean age was 49.6 years. The Kappa identity tests identified the agreement between the FTMS and intraoperative findings in evaluating the neurovascular relationship and offending vessel was 0.263 and 0.643, respectively. The agreement between the 3D-reconstruction and intraoperative findings was 0.633 and 0.921 respectively. There was borderline significant difference between the two methods in predicting neurovascular relationship (χ2 = 9.363, P = 0.053), and there were significant differences between the two methods in predicting offending vessels (χ2 = 188.408, P < 0.001). The sensitivity and specificity of FTMS in evaluating the neurovascular relationship were 89.7% and 100%, respectively, while those with 3D-reconstruction were both 100%. Moreover, the correct 3D- reconstruction examinations in predicting vessel and nerve relationships (r = 0.634, P = 0.034) and offending vessels (r = 0.652, P = 0.028) were significantly correlated with completely symptoms remission.

Conclusions: The 3D-reconstuction synthesized by 3D Slicer program was more accurate than FTMS in preoperative evaluation of neurovascular relationship and offending vessel. The technique is expected to be helpful in preoperative evaluation.

Availability of data and material: The dataset used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Treatment of Pediatric Vaginal Rhabdomyosarcoma With the Use of a Real-Time Tracked Custom Applicator

Publication: Brachytherapy. May-Jun 2022;21(3):291-9. PMID: 35623721 | PDF

Authors: Morcos M, Vogel J, Garcia JR, Gomez-Lobo V, Bartolac S.

Institution: Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Medicine, Baltimore, MD, USA.

Abstract: Purpose: To describe the development, design, and implementation of a 3D printed MR-compatible pediatric vaginal multichannel brachytherapy cylinder. Safety and quality measures to ensure consistent treatment required innovative identification on MR and CT, and real-time tracking.

Methods and materials: A 4-year-old with vaginal botryoides rhabdomyosarcoma underwent MR-simulation with a custom 3D printed biocompatible resin cylinder with four channels to ensure dose optimization capability. A total of four identifier regions were designed into the applicator in order to utilize these for MR-visualization and real-time tracking. A biocompatible 3D printed cylinder was designed to meet dose objectives using an MR and CT compatible material. 3D Slicer was required for real-time tracking during treatment.

Results: Based on MR simulation, a treatment plan was created with dose differentials in the area of prior surgery versus normal vaginal tissue. Creation of a low dose CT scan on a mobile CT allowed CT visualization of the applicator for verification. Treatment was administered under the use of a real-time optical tracking with rotational and depth adjustments monitored.

Conclusions: This advanced integration of 3D printed MR and CT biocompatible material, with unique design features consistent with a multi-channel vaginal cylinder, and incorporation of real-time optical tracking ensured that no positional changes were required, allowed successful treatment with differential dosing for a post-operative pediatric vaginal rhabdomyosarcoma patient.

The Prognostic Impact of Preoperative Body Composition in Perihilar and Intrahepatic Cholangiocarcinoma

Publication: Hepatol Commun. 2022 May 26. PMID: 35616275 | PDF

Authors: Lurje I, Czigany Z, Eischet S, Bednarsch J, Ulmer TF, Isfort P, Strnad P, Trautwein C, Tacke F, Neumann UP, Lurje G.

Institution: Department of Hepatology and Gastroenterology, Campus Charité Mitte, Campus Virchow-Klinikum, Charité-Universitätsmedizin Berlin, Berlin, Germany.

Abstract: Cholangiocarcinoma (CCA) is a rare but highly aggressive malignancy of the biliary system. Although it is amenable to surgical resection in early disease, outcomes are frequently dismal. Here, we investigated the prevalence of body composition (BC) alterations and their prognostic role for surgical patients with intrahepatic (iCCA) and perihilar (pCCA) disease. Patients undergoing curative-intent surgery for iCCA or pCCA between 2010 and 2019 at University Hospital Aachen were included. Axial computed tomography images were retrospectively assessed with a segmentation tool, 3D Slicer at the level of the third lumbar vertebra to determine lumbar skeletal muscle (SM) index, mean SM radiation attenuation, and visceral fat area. The related BC pathologies sarcopenia, myosteatosis, visceral obesity, and sarcopenic obesity were determined using previously described cutoffs. A total of 189 patients (86 with iCCA, 103 with pCCA) were included. Alterations of BC were highly prevalent in iCCA and pCCA, respectively: sarcopenia, 33% (28/86) and 39% (40/103); myosteatosis, 66% (57/86) and 66% (68/103); visceral obesity, 56% (48/86) and 67% (69/103); sarcopenic obesity, 11% (9/86) and 17% (17/103). Sarcopenia and myosteatosis did not have a significant prognostic role for disease-free survival (DFS) and overall survival (OS). Patients with iCCA with sarcopenic obesity (n = 9) had significantly shorter OS than patients without sarcopenic obesity (n = 7; log-rank p = 0.002; median OS, 11 months and 31 months; 1-year mortality, 55.6% [5/9] and 22% [17/77]; 5-year mortality, 88.9% [8/9] and 61% [47/77], respectively). In multivariable analysis, only tumor-related risk factors remained prognostic for DFS and OS. Sarcopenic obesity may affect clinical outcomes after curative-intent surgery for iCCA, indicating that imaging-based analysis of BC may hold prognostic value for long-term survival and could aid preoperative patient selection.

HEARTBEAT4D: An Open-source Toolbox for Turning 4D Cardiac CT into VR/AR

Publication: J Digit Imaging. 2022 May 25. PMID: 35614275

Authors: Bindschadler M, Buddhe S, Ferguson MR, Jones T, Friedman SD, Otto RK.

Institution: Department of Pediatrics, Seattle Children's Heart Center and the University of Washington, Seattle, WA, USA.

Abstract: Four-dimensional data sets are increasingly common in MRI and CT. While clinical visualization often focuses on individual temporal phases capturing the tissue(s) of interest, it may be possible to gain additional insight through exploring animated 3D reconstructions of physiological motion made possible by augmented or virtual reality representations of 4D patient imaging. Cardiac CT acquisitions can provide sufficient spatial resolution and temporal data to support advanced visualization, however, there are no open-source tools readily available to facilitate the transformation from raw medical images to dynamic and interactive augmented or virtual reality representations. To address this gap, we developed a workflow using free and open-source tools to process 4D cardiac CT imaging starting from raw DICOM data and ending with dynamic AR representations viewable on a phone, tablet, or computer. In addition to assembling the workflow using existing platforms (3D Slicer and Unity), we also contribute two new features: 1. custom software which can propagate a segmentation created for one cardiac phase to all others and export to surface files in a fully automated fashion, and 2. a user interface and linked code for the animation and interactive review of the surfaces in augmented reality. Validation of the surface-based areas demonstrated excellent correlation with radiologists' image-based areas (R > 0.99). While our tools were developed specifically for 4D cardiac CT, the open framework will allow it to serve as a blueprint for similar applications applied to 4D imaging of other tissues and using other modalities. We anticipate this and related workflows will be useful both clinically and for educational purposes.

Three-Dimensional Evaluation of Maxillary Second Molar Position in Untreated Patients With Normal Occlusion: Implications for Preadjusted Appliance Prescriptions

Publication: J Orofac Orthop. 2022 May;83(3):172-180. PMID: 33783560

Authors: Goracci C, Ruellas AC, Nieri M, Crouch S, McNamara JA Jr, Franchi L.

Institution: Department of Medical Biotechnologies, University of Siena, Policlinico Le Scotte, Siena, Italy.

Abstract: A sample of 41 subjects (16 females, 25 males) was selected from the University of Michigan Growth Study (UMGS). Digital dental casts with fully erupted second molars in occlusion were chosen (mean age 14.9 ± 1.3 years). Digital measurements were recorded with the open source software 3D Slicer. The digital measurements of the UMGS sample were compared with the manual measurements collected by Andrews from his sample of untreated class I subjects with normal overbite and overjet. Two mixed effect models (sagittal and transversal inclinations) were performed. The "random effect" was represented by the subjects, while the "fixed effects" were the two compared groups, the side of the arch (right and left), and the group × side interaction. Outcome variables were sagittal and transversal inclinations of the upper second molars.


Evidence of Linear Bone Flap Resorption in Patients Undergoing Autologous Cranioplasty Following Decompressive Craniectomy: A 3D Slicer Segmented Analysis of Serial CT Images

Publication: World Neurosurg. 2022 May 18:S1878-8750(22)00677-5. PMID: 35597539

Authors: Spake CS, Goli R, Beqiri D, Crozier JW, Cielo DJ, Klinge PM, Svokos K, Woo AS.

Institution: Division of Plastic Surgery, The Warren Alpert Medical School of Brown University, Providence, RI, USA.

Abstract: Objectives: Autologous cranioplasty (CP) following decompressive craniectomy (DC) carries risk of bone flap resorption (BFR). The current literature offers limited information regarding the natural progression of BFR, and the rate at which it occurs. We aim to characterize the progression of BFR over time and elucidate risk factors for accelerated BFR.

Methods: A retrospective analysis was conducted on patients who underwent DC and autologous CP. Serial computed tomography (CT) images were used to quantify degree of BFR over time. Risk factors included age, diabetes, smoking status, flap fragmentation, defect size, and DC-CP time interval. Chi-square analyses and Student's t-tests were performed to examine differences between patients who experienced BFR and those who did not.

Results: Overall, 82% of patients demonstrated evidence of clinically relevant resorption on CT. On average, the bone flap decreased in volume by 36.7% within the first year, with a linear loss in volume after multiple years of follow-up. Individuals who developed greater BFR were significantly younger (43 ± 17 vs. 56 ± 12, p=0.022), had a lower incidence of diabetes (5.9% vs. 43%, p=0.037), and had more bone flap fragments (1.4 ± 0.67 vs. 1.00 ± 0, p <0.001) than those who did not.

Conclusion: Resorption following CP with cryopreserved bone appears to progress in a fairly linear and continuous fashion over time. Using serial CT images, we found a resorption rate of 82% at our institution. We identified several possible risk factors for resorption, including flap fragmentation, younger age, and absence of diabetes.

Custom Massive Allograft in a Case of Pelvic Bone Tumour: Simulation of Processing with Computerised Numerical Control vs. Robotic Machining

Publication: J Clin Med. 2022 May 15;11(10):2781. PMID: 35628908 | PDF

Authors: Vivarelli L, Govoni M, Attala D, Zoccali C, Biagini R, Dallari D.

Institution: Reconstructive Orthopaedic Surgery and Innovative Techniques-Musculoskeletal Tissue Bank, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy.

Abstract: The use of massive bone allografts after the resection of bone tumours is still a challenging process. However, to overcome some issues related to the processing procedures and guarantee the best three-dimensional matching between donor and recipient, some tissue banks have developed a virtual tissue database based on the scanning of the available allografts for using their 3D shape during virtual surgical planning (VSP) procedures. To promote the use of future VSP bone-shaping protocols useful for machining applications within a cleanroom environment, in our work, we simulate a massive bone allograft machining with two different machines: a four-axes (computer numerical control, CNC) vs. a five-axes (robot) milling machine. The allograft design was based on a real case of allograft reconstruction after pelvic tumour resection and obtained with 3D Slicer and Rhinoceros software. Machining simulations were performed with RhinoCAM and graphically and mathematically analysed with CloudCompare and R, respectively. In this case, the geometrical differences of the allograft design are not clinically relevant; however, the mathematical analysis showed that the robot performed better than the four-axes machine. The proof-of-concept presented here paves the way towards massive bone allograft cleanroom machining. Nevertheless, further studies, such as the simulation of different types of allografts and real machining on massive bone allografts, are needed.

Combination of Preoperative Multimodal Image Fusion and Intraoperative Dyna CT in Percutaneous Balloon Compression of Trigeminal Ganglion for Primary Trigeminal Neuralgia: Experience in 24 Patients

Publication: Front Surg. 2022 May 9;9:895394. PMID: 35615652 | PDF

Authors: Liao CC, Li JY, Wu KH, Jian ZH, Yi XF, Weng ZJ, Chen G.

Institution: Department of Neurosurgery, Zhuhai People's Hospital (Zhuhai Hospital Affifiliated With Jinan University, China), Zhuhai, China.

Abstract: Objective: We retrospectively assessed the surgical results of PBC with preoperative multimodal image fusion and intraoperative Dyna Computed Tomography (CT) in 24 patients with primary trigeminal neuralgia (PTN) to explore a valuable aid for Percutaneous balloon compression (PBC).

Methods: We studied the data of 24 patients with PTN. All patients underwent PBC and were assessed with preoperative multimodal image fusion [computed tomography (CT) and magnetic resonance imaging (MRI)] and intraoperative Dyna CT in the Department of Neurosurgery of Zhuhai People's Hospital between October 2020 and September 2021. Multimodal image fusion-three-dimensional (3D) reconstruction of CT and MRI data-was performed using 3D Slicer software, and preoperative evaluation was performed according to the results of image fusion. Dyna CT was used to dynamically observe the position and shape of the metallic hollow introducer and Fogarty catheter and balloon during the operation to guide the operation in real time. We performed follow-up assessments each month and summarized the clinical characteristics, surgical effects, and complications in all patients.

Results: Surgery was successful for all patients; the patients reported immediate pain relief. Surgical complications included facial numbness in 24 patients (100%), mild masseter weakness in three (12.5%), herpes zoster in three (12.5%), and balloon rupture in one (4.2%). None of the patients had serious surgical complications. The mean follow-up time was 9.6 ± 2.7 months. During the follow-up period, 22 patients (91.7%) experienced no recurrence of pain, and two patients (8.3%) experienced recurrence of pain, of which one underwent secondary PBC surgery.

Conclusions: Preoperative multimodal image reconstruction can help fully evaluate PBC surgery, clarify the etiology, and predict the volume of contrast medium required during the operation. It provided important assistance for PBC treatment of trigeminal neuralgia patients when preoperative multimodal image fusion is combined with intraoperative Dyna CT.

TITAN: An End-to-End Data Analysis Environment for the Hyperion™ Imaging System

Publication: Cytometry A. 2022 May;101(5):423-33. PMID: 35060322

Authors: Thirumal S, Jamzad A, Cotechini T, Hindmarch CT, Graham CH, Siemens DR, Mousavi P.

Institution: School of Computing, Queen's University, Kingston, Canada.

Abstract: Imaging Mass Cytometry (IMC) is a powerful high-throughput technique enabling resolution of up to 37 markers in a single fixed tissue section while also preserving in situ spatial relationships. Currently, IMC processing and analysis necessitates the use of multiple different software, labour-intensive pipeline development, different operating systems and knowledge of bioinformatics, all of which are a barrier to many potential users. Here we present TITAN - an open-source, single environment, end-to-end pipeline that can be utilized for image visualization, segmentation, analysis and export of IMC data. TITAN is implemented as an extension within the publicly available 3D Slicer software. We demonstrate the utility, application, reliability and comparability of TITAN using publicly available IMC data from recently-published breast cancer and COVID-19 lung injury studies. Compared with current IMC analysis methods, TITAN provides a user-friendly, efficient single environment to accurately visualize, segment, and analyze IMC data for all users.

Kidney Hypertrophy in Living Kidney Donors and Their Corresponding Recipients

Publication: Transplant Proc. 2022 Apr;54(3):627-31. PMID: 35248353

Authors: Steden K, Figiel J, Hoyer J, Kamalanabhaiah SR.

Institution: Department of Nephrology, University Hospital of Marburg, UKGM GmbH, Marburg, Germany.

Abstract: Background: In this long-term study we compared kidney volume changes and function between living kidney donors and their corresponding recipients via magnetic resonance imaging after 3 to 8 years post transplantation.

Methods: For measurement of the kidney volume in magnetic resonance imaging images we used 3D Slicer. Statistical analysis was performed via t test and correlation.

Results: A profound volume increase was observed in both transplanted and orthotopic kidney. The volume increase of the orthotopic kidneys was with 58 cm³ ± 23.8 cm³ SD (41%) greater than in the corresponding transplanted kidneys with 43 cm³ ± 36.9 cm³ SD (30%).

Conclusions: This study detected a persistent volume increase in both orthotopic and transplanted kidneys after donation. Neither significant increases of hypertension or proteinuria were observable or could be correlated to renal hypertrophy.

Hematoma Segmentation of Spontaneous Intracerebral Hemorrhage Based on Watershed and Region-Growing Algorithm

Publication: Sichuan Da Xue Xue Bao Yi Xue Ban. 2022 May;53(3):511-6. PMID: 35642163

Authors: Zhao JY, Zhou ZS, Wang XY, Zhang HY, Duan ZH, Wang SM, Wan HL, Zhang T.

Institution: Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu, China.

Abstract: Objective: To establish a brain hematoma CT image segmentation method based on watershed and region-growing algorithm so as to measure hematoma volume quickly and accurately, to explore the consistency between the results of this segmentation method and those of manual segmentation, the clinical gold standard, and to compare the results of this method with the calculation of the two Tada formulas commonly used in clinical practice.

Methods: The preoperative CT images of 152 patients who were treated for spontaneous cerebral hemorrhage at the Department of Neurosurgery, West China Hospital, Sichuan University between January 2018 and June 2019 were retrospectively collected. The CT images were randomly assigned, by using a random number table, to the training set, the test set and the validation set, which contained 100 patients, 22 patients and 30 patients, respectively. The labeling results of the training set and the test set were used in algorithm training and testing. Four methods, namely, manual segmentation, algorithm segmentation, i.e., segmentation calculation based on watershed and regional growth algorithm, Tada formula, i.e., the traditional Tada formula calculation, and accurate Tada formula, i.e., accurate Tada formula calculation based on 3D Slicer, were applied on the validation set to measure the hematoma volume. The Digital Imaging and Communications in Medicine (DICOM) data of subjects meeting the selection criteria of the study were manually segmented by two experienced neurosurgeons. The hematoma segmentation model was built based on watershed algorithm and regional growth algorithm. Seed point selected by neurosurgeons was taken as the starting point of growth. Regional grayscale difference criterion combined with manual segmentation validation were adopted to determine the regional growth threshold that met the segmentation precision requirements for intracranial hematoma. Using manual segmentation as the gold standard, Bland-Altman consistency analysis was used to verify the consistency of the three other methods for measuring hematoma volume.

Results: With manual segmentation as the gold standard, among the three methods of measuring hematoma volume, algorithm segmentation had the smallest percentage error, the narrowest range of difference, the highest intra-group correlation coefficient (0.987), good consistency, and the narrowest 95% limits of agreement ( LoA). The percentage error of its segmentation was not statistically significant for hematomas of different volumes.

Conclusion: The segmentation method of spontaneous intracerebral hemorrhage based on watershed and regional growth algorithm shows stable measurement performance and good consistency with the clinical gold standard, which has considerable clinical significance, but it still needs further validation with more clinical samples.

Virtual Planning and Rapid 3D Prototyping Surgical Guide for Anterior Crown Lengthening Surgery: A Clinical Case Report

Publication: J Prosthodont. 2022 Apr;31(4):275-81. PMID: 34932246

Authors: Kim J, Lin YC, Danielak M, Van M, Lee DH, Kim H, Arany PR.

Institution: Department of Oral Biology, School of Dental Medicine, University at Buffalo, NY, USA.

Abstract: Progress with additive 3D printing is revolutionizing biomaterial manufacturing, including clinical dentistry and prosthodontics. Among the several 3D additive printing technologies, stereolithography is very popular as it utilizes light-activated resin for precise resolution. A simplified digital technique was used to fabricate two designs of a surgical guide for crown lengthening. Two cases are presented that utilized digital DICOM files obtained with computed tomography (CT) imaging and processed using four CAD software (Blue Sky Plan, Exocad, Meshmixer and 3D Slicer). The final models were converted to standard tesselation (STL) files and the guides were 3D printed with an additive sterelithography (SLA) printer. The first case was fabricated with a bone model from CBCT data, and the second case was generated with intraoral and wax-up scans alone. Both methods appear to be equally effective compared to using a conventional method of guide fabrication. However, proximal bone reduction was a concern with both designs. Digitally fabricated 3D printed surgical guide for crown lengthening has merit and a practical design is needed for future clinical validation. This article is protected by copyright. All rights reserved.

A New Simple, Cost-Effective Navigation System (EASY Navigator) for Neurosurgical Interventions

Publication: World Neurosurg. 2022 Apr 29;164:143-7. PMID: 35490891

Authors: Faraj MK, Kailan SL, Al-Neami AQH.

Institution: Department of Surgery, Consultant Neurosurgeon, College of Medicine, University of Baghdad, Baghdad, Iraq.

Abstract: Navigation technique facilitates reaching deeply seated masses more precisely with the least sacrifice of normal tissues. There are 2 primary navigation systems: electromagnetic and infrared (optical). The technique is based on recording the head position intraoperatively and merging this image with preoperative magnetic resonance imaging.

Methods: We tried to replace these conventional navigating systems with a simple technique using free software, 3D Slicer and a computer air mouse. The study was designed into 3 stages. In stage 1, we used this method on 3-dimensional printed models of patients' magnetic resonance images with deeply seated brain tumors. In stage 2, we performed the surgeries on patients. In the last stage, we used both the conventional navigation system with our method simultaneously on the same patients and compared the accuracy of both methods.

Results: This new system was as accurate as conventional navigating systems, ranging from ±2 mm.

Conclusions: This new technique, if done properly, can replace conventional methods with less time of preparation, and its cost is almost free.

3D Visualization of Perianal Fistulas Using Parametric Models

Publication: Tech Coloproctol. 2022 Apr;26(4):291-300. PMID: 35094202

Authors: Navkar NV, Balakrishnan S, Kharbech S, Sabawi M, Abinahed J, Ahmed A, Al-Ansari A, Omar A, Khanna M, Darweesh A.

Institution: Department of Surgery, Hamad General Hospital, Hamad Medical Corporation, Doha, Qatar.

Abstract: Background: Magnetic resonance imaging (MRI) is used as a standard for assessment of complex perianal fistulas. Apart from textual description of the case, 3D reconstructed models from MRI further aid in understanding the entire anatomy of the fistula tract and its relation to the pelvic floor. This information is crucial as it helps surgeons to understand the extent and complexity of the disease before surgical treatment. However, 3D model generation from MRI is a time-consuming step for a radiologist as it requires tedious manual delineations to be performed on every slice of the images. The aim of this study was to develop a method that could enable radiologists to present enhanced information to surgeons for treatment of complex perianal fistulas while simultaneously reducing the manual efforts and time required to generate the information.

Methods: A method was proposed to depict relevant anatomies of complex perianal fistula as parametric models in three-dimensional (3D) space. A plugin inside 3D Slicer software was developed for the generation of the parametric models from MRI. The levator ani muscle, internal sphincter, and external sphincter are represented as tubular structures, whereas fistula tracks and abscess are presented as splines.

Results: Parametric models were generated to depict three cases of complex perianal fistulas and similarity measures were computed for ten cases. Visual comparison of the parametric models was made with the 3D models generated by the standard approach. The parametric models took less time to create and were able to visually present enriched information as compared to the 3D models generated by the standard approach.

Conclusions: The proposed method, using parametric models, shows potential for faster generation and better visualization of the 3D information required for the treatment of complex perianal fistula cases.

Optimized Tractography Mapping and Quantitative Evaluation of Pyramidal Tracts for Surgical Resection of Insular Gliomas: a Correlative Study with Diffusion Tensor Imaging-Derived Metrics and Patient Motor Strength

Publication: J Digit Imaging. 2022 Apr;35(2):356-64. PMID: 35064370

Authors: Li Y, Hou Y, Li Q, Tang J, Lu J.

Institution: Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.

Abstract: We investigate the correlation between diffusion tensor imaging (DTI)-derived metric statistics and motor strength grade of insular glioma patients after optimizing the pyramidal tract (PT) delineation. Motor strength grades of 45 insular glioma patients were assessed. All the patients underwent structural and diffusion MRI examination before and after surgery. We co-registered pre- and post-op datasets, and a two-tensor unscented Kalman filter (UKF) algorithm was employed to delineate bilateral PTs after DWI pre-processing. The tractography results were voxelized, and their labelmaps were cropped according to the location of frontal and insular parts of the lesion. Both the whole and cropped labelmaps were used as regions of interest to analyze fractional anisotropy (FA) and Trace statistics; hence, their ratios were calculated (lesional side tract/contralateral normal tract). The combination of DWI pre-processing and two-tensor UKF algorithm successfully delineated bilateral PTs of all the patients. It effectively accomplished both full fiber delineation within the edema and an extensive lateral fanning that had a favorable correspondence to the bilateral motor cortices. Before surgery, correlations were found between patients' motor strength grades and ratios of PT volume and FA standard deviation (SD). Nearly 3 months after surgery, correlations were found between motor strength grades and the ratios of metric statistics as follows: whole PT volume, whole mean FA, and FA SD. We substantiated the correlation between DTI-derived metric statistics and motor strength grades of insular glioma patients. Moreover, we posed a workflow for comprehensive pre- and post-op DTI quantitative research of glioma patients.

Keywords: 3D Slicer; Diffusion tensor imaging; Insular glioma; Pyramidal tracts.

The Significance of Nanoparticles in Brain Cancer Diagnosis and Treatment: Modeling and Simulation

Publication: Biomed Phys Eng Express. 2022 Apr 22;8(3). PMID: 35405668

Authors: Badawi MI, Hafez KS.

Institution: Biomedical Equipment Technology Department, Faculty of Applied Health Sciences Technology, Pharos University, Alexandria, Egypt.

Abstract: A numerical analysis of specific absorption rate (SAR) and temperature distributions in a realistic human head model is presented in this study. The key challenge is to rise cancer temperature to an optimal temperature without heating nearby healthy tissues. The model's uniqueness is that it captures the effect of nanoparticles on both brain cancer diagnosis and treatment. A realistic human head model with a cancerous brain segmented from 2D magnetic resonance imaging (MRI) gained from an actual patient using 3D Slicer, modeled, and simulated using CST-Microwave Studio, and illuminated by Archimedes spiral antenna. At frequencies of 2450 MHz and 915 MHz, the model simulated the absence and presence of various nanoparticles. The obtained results suggest that when using nanoparticles, it is possible to achieve sufficient energy deposition and temperature rise to therapeutic values (greater than 42 °C) in brain cancers using the proposed noninvasive hyperthermia system at 915 MHz frequency, especially for gold nanoparticles, without harming surrounding healthy tissue. Our research might pave the way for a clinical applicator prototype that can heat brain cancer.

Surgically Assisted Maxillary Expansion With or Without Pterygoid Disjunction Alters Maxillomandibular Positioning

Publication: Oral Maxillofac Surg. 2022 Apr 15. PMID: 35426586

Authors: Carvalho FSR, Soares ECS, de Medeiros JR, Júnior JMM, Hyppolito JOP, de Barros Silva PG, Ribeiro TR, Costa FWG.

Institution: Department of Oral and Maxillofacial Surgery, Federal University of Ceará Campus Sobral, Sobral, Ceará, Brazil.

Abstract: Purpose: This study aimed to analyze alterations in mandibular positioning after surgically assisted maxillary expansion (SARME) with and without pterygoid disjunction (PD).

Methods: Cone-beam computed tomography scans of 24 healthy individuals (18-45 years old) with transverse deficiency, superior to 5 mm, underwent SARME with or without PD. The aspects prospectively assessed were (1) alignment and position of the head (ITK-Snap and 3D Slicer software); (2) McNamara's and Steiner-Tweed-Wits' cephalometric analysis (Dolphin Imaging®); and (3) colorimetric evaluation based on 3D correspondence analysis (3D Slicer software).

Results: A decrease in 1-NA and 1-SN angles as well as an increased occlusal plane in both groups was observed. Superior-inferior and anteroposterior spatial displacements of the chin were statistically significant in the PD group. Altered colorimetric patterns were also observed in the PD group.

Conclusions: This study found more evident tooth inclination in the group without PD; mandibular alterations were more evident in the PD group. Further studies with 3D analysis are strongly recommended for more comprehensive results.

Reproducibility for Hepatocellular Carcinoma CT Radiomic Features: Influence of Delineation Variability Based on 3D-CT, 4D-CT and Multiple-Parameter MR Images

Publication: Front Oncol. 2022 Apr 14;12:881931. PMID: 35494061 | PDF

Authors: Duan J, Qiu Q, Zhu J, Shang D, Dou X, Sun T, Yin Y, Meng X.

Institution: School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin, China.

Abstract: Purpose: Accurate lesion segmentation is a prerequisite for radiomic feature extraction. It helps to reduce the features variability so as to improve the reporting quality of radiomics study. In this research, we aimed to conduct a radiomic feature reproducibility test of inter-/intra-observer delineation variability in hepatocellular carcinoma using 3D-CT images, 4D-CT images and multiple-parameter MR images.

Materials and methods: For this retrospective study, 19 HCC patients undergoing 3D-CT, 4D-CT and multiple-parameter MR scans were included in this study. The gross tumor volume (GTV) was independently delineated twice by two observers based on contrast-enhanced computed tomography (CECT), maximum intensity projection (MIP), LAVA-Flex, T2W FRFSE and DWI-EPI images. We also delineated the peritumoral region, which was defined as 0 to 5 mm radius surrounding the GTV. 107 radiomic features were automatically extracted from CECT images using 3D Slicer software. Quartile coefficient of dispersion (QCD) and intraclass correlation coefficient (ICC) were applied to assess the variability of each radiomic feature. QCD<10% and ICC≥0.75 were considered small variations and excellent reliability. Finally, the principal component analysis (PCA) was used to test the feasibility of dimensionality reduction.

Results: For tumor tissues, the numbers of radiomic features with QCD<10% indicated no obvious inter-/intra-observer differences or discrepancies in 3D-CT, 4D-CT and multiple-parameter MR delineation. However, the number of radiomic features (mean 89) with ICC≥0.75 was the highest in the multiple-parameter MR group, followed by the 3DCT group (mean 77) and the MIP group (mean 73). The peritumor tissues also showed similar results. A total of 15 and 7 radiomic features presented excellent reproducibility and small variation in tumor and peritumoral tissues, respectively. Two robust features showed excellent reproducibility and small variation in tumor and peritumoral tissues. In addition, the values of the two features both represented statistically significant differences among tumor and peritumoral tissues (P<0.05). The PCA results indicated that the first seven principal components could preserve at least 90% of the variance of the original set of features.

Conclusion: Delineation on multiple-parameter MR images could help to improve the reproducibility of the HCC CT radiomic features and weaken the inter-/intra-observer influence.

Pseudoprogression Prediction in High Grade Primary CNS Tumors by Use of Radiomics

Publication: Sci Rep. 2022 Apr 8;12(1):5915. PMID: 35396525 | PDF

Authors: Ari AP, Akkurt BH, Musigmann M, Mammadov O, Blömer DA, Kasap DNG, Henssen DJHA, Nacul NG, Sartoretti E, Sartoretti T, Backhaus P, Thomas C, Stummer W, Heindel W, Mannil M.

Institution: University Clinic for Radiology, Westfälische Wilhelms-University Muenster and University Hospital Muenster, Albert-Schweitzer-Campus 1, Muenster, Germany.

Abstract: Our aim is to define the capabilities of radiomics and machine learning in predicting pseudoprogression development from pre-treatment MR images in a patient cohort diagnosed with high grade gliomas. In this retrospective analysis, we analysed 131 patients with high grade gliomas. Segmentation of the contrast enhancing parts of the tumor before administration of radio-chemotherapy was semi-automatically performed using the 3D Slicer open-source software platform (version 4.10) on T1 post contrast MR images. Imaging data was split into training data, test data and an independent validation sample at random. We extracted a total of 107 radiomic features by hand-delineated regions of interest (ROI). Feature selection and model construction were performed using Generalized Boosted Regression Models (GBM). 131 patients were included, of which 64 patients had a histopathologically proven progressive disease and 67 were diagnosed with mixed or pure pseudoprogression after initial treatment. Our Radiomics approach is able to predict the occurrence of pseudoprogression with an AUC, mean sensitivity, mean specificity and mean accuracy of 91.49% [86.27%, 95.89%], 79.92% [73.08%, 87.55%], 88.61% [85.19%, 94.44%] and 84.35% [80.19%, 90.57%] in the full development group, 78.51% [75.27%, 82.46%], 66.26% [57.95%, 73.02%], 78.31% [70.48%, 84.19%] and 72.40% [68.06%, 76.85%] in the testing group and finally 72.87% [70.18%, 76.28%], 71.75% [62.29%, 75.00%], 80.00% [69.23%, 84.62%] and 76.04% [69.90%, 80.00%] in the independent validation sample, respectively. Our results indicate that radiomics is a promising tool to predict pseudo-progression, thus potentially allowing to reduce the use of biopsies and invasive histopathology.

Radiomics Analysis Based on Lumbar Spine CT to Detect Osteoporosis

Publication: Eur Radiol. 2022 Apr 30:1-8. PMID: 35499565 | PDF

Authors: Jiang YW, Xu XJ, Wang R, Chen CM.

Institution: Department of Neurosurgery, Fujian Medical University Union Hospital, No. 29, Xin Quan Road, Fuzhou City, Fujian Province, China.

Abstract: Objectives: Undiagnosed osteoporosis may lead to severe complications after spinal surgery. This study aimed to construct and validate a radiomic signature based on CT scans to screen for lumbar spine osteoporosis.

Methods: Using a stratified random sample method, 386 vertebral bodies were randomly divided into a training set (n = 270) and a test set (n = 116). A total of 1040 radiomics features were automatically retracted from lumbar spine CT scans using the 3D Slicer pyradiomics module, and a radiomic signature was created. The sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) of the Hounsfield and radiomics signature models were calculated. The AUCs of the two models were compared using the DeLong test. Their clinical usefulness was assessed using a decision curve analysis.

Results: Twelve features were chosen to establish the radiomic signature. The AUCs of the radiomics signature and Hounsfield models were 0.96 and 0.88 in the training set and 0.92 and 0.84 in the test set, respectively. According to the DeLong test, the AUCs of the two models were significantly different (p < 0.05). The radiomics signature model indicated a higher overall net benefit than the Hounsfield model, as determined by decision curve analysis.

Conclusions: The CT-based radiomic signature can differentiate patients with/without osteoporosis prior to lumbar spinal surgery. Without additional medical cost and radiation exposure, the radiomics method may provide valuable information facilitating surgical decision-making.

Key points: • The goal of the study was to evaluate the efficacy of a radiomics signature model based on routine preoperative lumbar spine CT scans in screening osteoporosis. • The radiomics signature model demonstrated excellent prediction performance in both the training and test sets. • This radiomics method may provide valuable information and facilitate surgical decision-making without additional medical costs and radiation exposure.

Characterization of Volumetric Growth of Intracranial Meningiomas in Māori and Pasifika Populations in New Zealand

Publication: ANZ J Surg. 2022 Apr;92(4):848-55. PMID: 35239240

Authors: Davis B, Beldishevski-Shotadze O, Ibrahim Z, McHugh F, Turner C, Olson S, Faull R, Dragunow M, Law AJJ, Correia JA.

Institution: Department of Neurosurgery, Auckland City Hospital, Grafton, Auckland, New Zealand.

Abstract: Background: Māori and Pasifika populations in New Zealand have a higher incidence and prevalence of intracranial meningioma (IM). We sought to evaluate the volumetric growth rate of meningiomas under surveillance in these populations.

Methods: From July 2002 to October 2020, 336 patients with a total of 408 IM underwent conservative management with serial radiological surveillance at Auckland City Hospital and met the criteria for the study. Inclusion criteria included: age >16 at diagnosis, ≥2 appropriate scans one or more years apart. Exclusion criteria included previous cranial irradiation, a diagnosis of Neurofibromatosis and prior treatment of meningioma. Demographic and clinical data were obtained from the electronic medical records. Imaging data were recorded from the first and last scans. We utilized open-source image processing software, 3D Slicer for semi-automated segmentation and volume calculation. Consistent with previous literature, we calculated the relative growth rate (RGR, %/year) and annual volume change (AVC, cm3 /year) over time.

Results: Four hundred and eight meningiomas were volumetrically characterized for a mean duration of 6.2 years. The Māori and Pasifika populations (n = 134/393) demonstrated a higher RGR (31.41 versus 14.33%/year) (P = 0.026) and AVC (2.05 versus 0.95 cm3 ) (P = 0.025) compared to the control population. They also presented at a younger age and had a higher rate of tumour multiplicity. Males represented only 17.6% of the cohort but exhibited a higher growth rate (AVC = 2.52 cm3 /year) than females (AVC = 0.99 cm3 /year) (P = 0034).

Conclusions: Māori and Pasifika populations in New Zealand have a higher incidence and volumetric growth rate of IM compared to a control population. This warrants further clinical, histopathological and genomic analysis.

Poly(L-Co-D,L Lactic Acid-Co-Trimethylene Carbonate) 3D Printed Scaffold Cultivated With Mesenchymal Stem Cells Directed to Bone Reconstruction: In Vitro and in Vivo Studies

Publication: J Biomater Appl. 2022 Apr;36(9):1550-66. PMID: 35130780

Authors: Asami J, Hausen MA, Komatsu D, Ferreira LM, Silva GBG, da Silva LCSC, Baldo DA, Oliveira Junior JM, Motta AC, Duek EAR.

Institution: Federal University of Sao Carlos (UFSCar), Sorocaba, SP, Brazil.

Abstract: A recent and quite promising technique for bone tissue engineering is the 3D printing, peculiarly regarding the production of high-quality scaffolds. The 3D printed scaffold strictly provides suitable characteristics for living cells, in order to induce treatment, reconstruction and substitution of injured tissue. The purpose of this work was to evaluate the behavior of the 3D scaffold based on Poly(L-co-D,L lactic acid-co-Trimethylene Carbonate) (PLDLA-TMC), which was designed in Solidworks™ software, projected in 3D Slicer™, 3D printed in filament extrusion, cultured with mesenchymal stem cells (MSCs) and tested in vitro and in vivo models. For in vitro study, the MSCs were seeded in a PLDLA-TMC 3D scaffold with 600 μm pore size and submitted to proliferation and osteogenic differentiation. The in vivo assays implanted the PLDLA-TMC scaffolds with or without MSCs in the calvaria of Wistar rats submitted to 8 mm cranial bone defect, in periods of 8-12 weeks. The results showed that PLDLA-TMC 3D scaffolds favored adherence and cell growth, and suggests an osteoinductive activity, which means that the material itself augmented cellular differentiation. The implanted PLDLA-TMC containing MSCs, showed better results after 12 weeks prior grafting, due the absence of inflammatory processes, enlarged regeneration of bone tissue and facilitated angiogenesis. Notwithstanding, the 3D PLDLA-TMC itself implanted enriched tissue repair; the addition of cells known to upregulate tissue healing reinforce the perspectives for the PLDLA-TMC applications in the field of bone tissue engineering in clinical trials.

Comparing Three-Dimensional Models of Placenta Accreta Spectrum With Surgical Findings

Publication: Int J Gynaecol Obstet. 2022 Apr;157(1):188-97. PMID: 33998689

Authors: Mulligan KM, Bartels HC, Armstrong F, Immel E, Corcoran S, Walsh JM, McAuliffe F, McParland P, Carroll S, Higgins S, Mahony R, Donnelly J, Geoghegan T, Colleran G, O'Cearbhaill E, Downey P, Brennan DJ.

Institution: UCD School of Medicine, National Maternity Hospital, Dublin, Ireland.

Abstract: Objective: Placenta accreta spectrum (PAS) is associated with significant maternal morbidity mainly related to blood loss. Pre-operative planning is aided by antenatal ultrasound and magnetic resonance imaging. We sought to assess whether three-dimensional (3D) models from MR images were accurate when compared with surgical and pathological findings.

Methods: Digital Imaging and Communications in Medicine files containing MR images with varying severity of PAS (n = 4) were modeled using 3D Slicer. Placenta, bladder, and myometrial defects were modeled. Myometrial defects at three different uterine locations were included-anterior, lateral and inferior. 3D models were used to identify the relationship between the myometrial defect and the internal cervical os. Findings were validated in a larger series of PAS cases (n = 14) where patterns of invasion were compared with estimated blood loss and distance from defect to the internal os.

Results: The defect illustrated in the four 3D models correlates to both surgical and pathological findings in terms of depth and pattern of invasion, location of defect, bladder involvement. Blood loss and topography of the defect from 3D modeling were examined in 14 further cases. Inferior defects were associated with increased blood loss compared with anterior defects. Increased distance from cervix was associated with reduced blood loss (R2 = 0.352, P = 0.01).

Conclusion: Three-dimensional models of PAS provide an accurate preoperative description of placental invasion and should be investigated as a tool for selecting patients for uterine-conserving surgery. Accurate 3D models of placenta accreta spectrum are achievable and may provide additional information, such as distance of the defect from the internal os.

Giant Pediatric Supratentorial Tumor: Clinical Feature and Surgical Strategy

Publication: Front Pediatr. 2022 Apr 26;10:870951. PMID: 35558365 | PDF

Authors: Zhang ZD, Fang HY, Pang C, Yang Y, Li SZ, Zhou LL, Bai GH, Sheng HS.

Institution: Department of Neurosurgery, The Second Affiliated Hospital and Yuying Children's Hospital of Wenzhou Medical University, Wenzhou, China.

Abstract: To analyze the clinical character of giant pediatric supratentorial tumor (GPST) and explore prognostic factors.

Materials and methods: We analyzed the clinical data comprising of 35 cases of GPST from a single center between January 2015 and December 2020. The tumor volume was measured by 3D Slicer software based on preoperative magnetic resonance imaging (MRI). Glasgow Outcome Scale (GOS) was used to evaluate the short-term prognosis.

Result: The tumor volume varied from 27.3 to 632.8 ml (mean volume 129.8 ml/ median volume 82.8 ml). Postoperative histopathological types include ependymoma, pilocytic astrocytoma, choroid plexus papilloma (CPP), craniopharyngioma, primitive neuroectodermal tumor (PNET), choroid plexus carcinoma (CPC), immature teratoma, atypical teratoid rhabdoid tumor (AT/RT), anaplastic astrocytoma, and gangliocytoma. Tumors in children younger than 3 years and tumors located at the hemispheres appeared to be larger than their respective counterparts, though no statistical significance was found. A patient with giant immature teratoma died during the operation because of excessive bleeding. Postoperative complications include cerebrospinal fluid subgaleal collection/effusion, infection, neurological deficits, and seizures. The mean GOS score of patients with GPST in 6 months is 3.43 ± 1.12, and 83% of patients (29/35) showed improvement. Favorable GPST characteristics to indicated better GOS included small tumor (≤100 ml) (p = 0.029), low-grade (WHO I-II) (p = 0.001), and gross total resection (GTR) (p = 0.015). WHO grade was highly correlated with GOS score (correlation coefficient = -0.625, p < 0.001). GTR and tumor volume were also correlated (correlation coefficient = -0.428, p = 0.010).

Conclusion: The prognosis of GPST is highly correlated with the histopathological type. Smaller tumors are more likely to achieve GTR and might lead to a higher GOS score. Early diagnosis and GTR of the tumor are important for GPST management.

Volumetric Assessment of Changes in the Alveolar Ridge Dimension Following GBR Using a Combination FDBA With Collagen Membrane or Novel Resorbable Scaffold: A Prospective Two-Center Clinical Trial

Publication: J Periodontol. 2022 Mar;93(3):343-53. PMID: 34245016

Authors: Dowlatshahi S, Chen CY, Zigdon-Giladi H, Horwitz J, Ahn C, Kim DM, Machtei EE.

Institution: Division of Periodontology, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA.

Abstract: Background: The aim of this study was to examine osseous changes following lateral bone augmentation using a novel Ossix Volumax (OV) scaffold alone and compare it to combination therapy using freeze-dried bone allograft (FDBA) and resorbable collagen membrane (FDBA/CM).

Methods: Thirty patients completed this 9-months prospective two-center cohort clinical trial. Before surgery and 9-months re-entry, linear measurements were performed, and impressions taken. Cone-beam computed tomography (CBCT) were done at baseline and 9 months. DICOM slice data were converted into volumetric images using 3D Slicer. Following 3D volumetric image construction, pre- and post-op Standard Triangle Language files were superimposed and volumetric data were extracted for a 10-mm region of interest. Linear measurements were compared similarly.

Results: Baseline clinical parameters were similar in both groups (4.22 and 4.53 mm for OV and FDBA/CM at -2 mm, respectively). Following treatment, vertical distance from the stent had changed minimally (-0.36 and -0.12 mm, respectively). Similarly, lateral bone gain ranged from 0 to 0.4 mm, for both groups. To the contrary, the CBCT measurements showed a significantly greater increase in horizontal width in the control at -2 mm (0.95 ± 0.2 mm) compared with -0.62 mm for the OV (P = 0.000). Similar changes were observed at -5 mm (0.63 and -0.41 mm, respectively, P = 0.01). Sites volume had increased from 266 ± 149 mm3 to 360 ± 138 mm3 (P = 0.001) for FDBA/CM with negligible changes for OV (from 334 to 335 mm3 , P = 0.952). these between-group changes being statistically significant (P = 0.023).

Conclusion: FDBA/CM yielded better albeit moderate increase in the volume of the edentulous ridge, while OV scaffolds failed to produce similar results.

Choroidal Macrovessel: Systematic Review and Analysis of Anatomic Origin

Publication: Surv Ophthalmol. 2022 Mar-Apr;67(2):570-8. PMID: 34332961

Authors: Bowen RC, Raval V, Soto H, Singh AD.

Institution: Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA.

Abstract: There are various hypotheses for the anatomic origin of a choroidal macrovessel. We assess whether a choroidal macrovessel is a dilated posterior ciliary artery. A systematic review of published literature on choroidal macrovessels was performed with two additional cases from our institution. We compared the visible entry and vascular course of the macrovessel in the published literature. We performed a comparative analysis using indocyanine green angiography, swept source optical computed tomography, and 3D reconstruction of two choroidal macrovessels using 3D Slicer (Harvard, Boston, USA). From the 14 studies found, 18 cases met inclusion criteria. The reported literature and our two cases showed a radiating course along a sectoral distribution pattern of either short or long posterior ciliary arteries. Our review of literature and 3D reconstruction analysis support the hypothesis that choroidal macrovessels are dilated posterior ciliary arteries.

Using Three-Dimensional Visualization as an Optimal Tool to Plan and Validate an Aortopexy in a Congenital Heart Disease Patient With Severe Tracheal Stenosis

Publication: Interact Cardiovasc Thorac Surg. 2022 Mar 31;34(4):708-10. PMID: 34738096

Authors: Kehl T, van Rüth V, Weinrich JM, Hübler M.

Institution: Clinic for Children's Heart Medicine, University Heart & Vascular Center, University Hospital Hamburg-Eppendorf, Hamburg, Germany.

Abstract: We present a patient with severe tracheal stenosis resulting from a compression by the innominate artery 6 months after an arterial switch operation in a dextro-transposition of the great arteries. Segmentation and three-dimensional (3D) visualization were derived from a contrast-enhanced dual-source computed tomography and post-processing was performed using a dedicated open-source platform, 3D Slicer. Post-processing allowed a comprehensible visualization of the relationship of the innominate artery to the trachea when compared to standard computer tomography reformations. Finally, the surgical approach to move the innominate artery anteriorly in order to relieve the tracheal obstruction was emphasized based on the improved 3D visualization of the actual pathology. An effective aortopexy could be performed and the postoperative result was confirmed by a second 3D visualization. About 3 months of follow-up, the patient is completely asymptomatic. Three-dimensional visualization offers excellent opportunities for diagnosis, treatment planning and follow-up in patients with a vascular-related tracheal stenosis in the context of congenital heart disease.

Bladder Urothelial Carcinoma: Machine Learning-based Computed Tomography Radiomics for Prediction of Histological Variant

Publication: Acad Radiol. 2022 Mar 26:S1076-6332(22)00116-7. PMID: 35351362

Authors: Evrimler S, Ali Gedik M, Ahmet Serel T, Ertunc O, Alperen Ozturk S, Soyupek S.

Institution: Department of Radiology, Suleyman Demirel University School of Medicine, Isparta, Turkey.

Abstract: Rationale and objectives: Histological variant (HV) of bladder urothelial carcinoma (UC) is a significant factor for therapy management. We aim to assess the predictive performance of machine learning (ML)-based Computed Tomography radiomics of UC for HV.

Materials and methods: Volume of interest of 37 bladder UC tumors, of which 21 were pure and 16 were HV, were manually segmented. The extracted first- and second-order texture features (n = 117) using 3D Slicer radiomics were compared to the radical cystectomy histopathological results. ML algorithms were performed to determine the significant models using Python 2.3, Pycaret library. The sample size was increased to 74 by synthetic data generation, and three outliers from the training set were removed (training dataset; n = 52, test dataset; n = 19). The predictive performances of 15 ML algorithms were compared. Then, the best two models were evaluated on the test set and ensembled by Voting Classifier.

Results: The ML algorithms demonstrated area under curve (AUC) and accuracy ranging 0.79-0.97 and 50%-90%, respectively on the train set. The best models were Gradient Boosting Classifier (AUC: 0.95, accuracy: 90%) and CatBoost Classifier (AUC: 0.97, accuracy: 85%). On the test set; the Voting Classifier of these two models demonstrated AUC, accuracy, recall, precision, and F1 scores as follows; 0.93, 79%, 86%, 67%, and 75%, respectively.

Conclusion: ML-based Computed Tomography radiomics of UC can predict HV, a prognostic factor that is indeterminable by qualitative radiological evaluation and can be missed in the preoperative histopathological specimens.

Semi-Automatic Segmentation of Cone Beam Computed Tomography Datasets for Volume Measurements of Equine Cheek Teeth

Publication: J Vet Dent. 2022 Mar;39(1):41-48. PMID: 34866465

Authors: Herren FL, Gerber V, Meier R, Schweizer-Gorgas D, Klopfenstein Bregger MD.

Institution: University of Bern, Switzerland.

Abstract: The volumes of equine teeth may change considerably over time for several reasons including domestication, routine dental floating, and the hypsodont and anelodont nature of the teeth. Cone beam computed tomography (CBCT) of the head is routinely performed in standing horses and, in this proof of concept study, the feasibility of measuring tooth volume from CBCT datasets was determined. The CBCT images of 5 equine cadaver cheek teeth were segmented with a 3D Slicer software using a predefined protocol, corrected manually, and re-assembled into a 3D model. Individual tooth volume (VS) was calculated from the model. After extraction, the volumes were also measured using the "gold-standard" water displacement method (VW) for comparison. The VS of 77 teeth ranged from 7114 to 42,300 mm3 which strongly correlated with VW (r = 0.99), and on average VS was 6.1% less than VW. There was no significant difference in VS between the right and left arcades in individual animals. Maxillary cheek tooth volume was on average 40% larger than it was for mandibular counterparts. Semi-automatic image segmentation of equine cheek teeth from CBCT data is feasible and accurate but requires some manual intervention. This preliminary study provides initial data on the volume of equine cheek teeth and creates new possibilities for future in vivo studies.

Radiomics-Based Artificial Intelligence Differentiation of Neurodegenerative Diseases with Reference to the Volumetry

Publication: Life (Basel). 2022 Mar 31;12(4):514. PMID: 35455005 | PDF

Authors: Cheung EYW, Chau ACM, Tang FH, On Behalf Of The Alzheimer's Disease Neuroimaging Initiative.

Institution: School of Medical Health and Sciences, Tung Wah College, Ho Man Tin, Hong Kong, China.

Abstract: This study aimed to build automated detection models-one by brain regional volume (V-model), and the other by radiomics features of the whole brain (R-model)-to differentiate mild cognitive impairment (MCI) from cognitive normal (CN), and Alzheimer's Disease (AD) from mild cognitive impairment (MCI). The objectives are to compare the models and identify whether radiomics or volumetry can provide a better prediction for differentiating different types of dementia.

Method: 582 MRI T1-weighted images were retrieved from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database, which is a multicenter operating open source database for AD. In total, 97 images of AD, 293 images of MCI patient and 192 images of cognitive normal were divided into a training, a validation and a test group at a ratio of 70:15:15. For each T1-weighted image, volumetric segmentation was performed with the image analysis software FreeSurfer, and radiomics features were retrieved by imaging research software 3D Slicer. Brain regional volume and radiomics features were used to build the V-model and R-model, respectively, using the random forest algorithm by R. The receiver operating characteristics (ROC) curve of both models were used to evaluate their diagnostic accuracy and reliability to differentiate AD, MCI and CN.

Results: To differentiate MCI and CN, both V-model and R-model achieved excellent performance, with an AUC of 0.9992 ± 0.0022 and 0.9850 ± 0.0032, respectively. No significant difference was found between the two AUCs, indicating both models obtained similar good performance. In MCI and AD differentiation, the V-model and R-model yielded AUC of 0.9986 ± 0.0013 and 0.9714 ± 0.0175, respectively. The best performance was to differentiate AD from CN, where the V-model and R-model yielded AUC of 0.9994 ± 0.0019 and 0.9830 ± 0.009, respectively. The results suggested that both volumetry and radiomics approaches could be used in differentiating AD, MCI and CN, based on T1 weighted MR images using random forest algorithm successfully.

Conclusion: This study showed that the radiomics features from T1-weighted MR images achieved excellence performance in differentiating AD, MCI and CN. Compared to the volumetry method, the accuracy, sensitivity and specificity are slightly lower in using radiomics, but still attained very good and reliable classification of the three stages of neurodegeneration. In view of the convenience and operator independence in feature extraction, radiomics can be a quantitative biomarker to differentiate the disease groups.

Optimized Fitting of a Midface Implant to Anchor a Magnetic Nasal Prosthesis Using 3D Printing

Publication: HNO. 2022 Mar;70(3):200-5. PMID: 34463790

Authors: Wrobel C, Keppeler D, Meyer AC.

Institution: Klinik für Hals-Nasen-Ohrenheilkunde, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Deutschland.

Abstract: Background: Plate-based anchorage systems for craniofacial prostheses offer advantages over extraoral solitary titanium implants in terms of the flexible choice of mounting points and higher stability. Disadvantages become apparent in the complex individual intraoperative adaptation of the plate-based systems to the usually poorly accessible bone. The current article presents a method to overcome these disadvantages and make greater use of the advantages of plate-based systems.

Materials and methods: The bony midface of a patient who had undergone rhinectomy for cancer of the nasal entrance was reconstructed as a virtual 3D model based on preoperative CT. The open-source software, 3D Slicer allowed easy and fast reconstruction as well as adaptation for 3D printing using transparent plastic (MED610; stratasys Ltd., MN, USA).

Results: A titanium mini-plate (MEDICON) for anchoring the nasal prosthesis could be fitted extremely precisely on the midface 3D print. Important anatomical structures were spared, and screw placement was selected according to the individual bone thickness. Implantation of the in-advance fitted titanium plate was performed without complications and without further adjustments.

Conclusion: In-advance fitting of plate-based systems for anchorage of craniofacial prostheses using 3D printing of the midface overcomes their disadvantages of time-consuming and possibly imprecise individual adaptation. This method further exploits the advantages of higher stability through more possible mounting points, even in thinner bone, to prevent loosening. In addition, in-advance fitting of titanium plates on the 3D model enables better identification and protection of important anatomical structures and shortens operative time.

Automatic Intra-Subject Registration and Fusion of Multimodal Cochlea 3D Clinical Images

Publication: PLoS One. 2022 Mar 2;17(3):e0264449. PMID: 35235600 | PDF

Authors: Al-Dhamari I, Helal R, Morozova O, Abdelaziz T, Jacob R, Paulus D, Waldeck S.

Institution: Computer Vision Department, Koblenz University, Koblenz, Germany.

Abstract: Background: The postoperative imaging assessment of Cochlear Implant (CI) patients is imperative. The main obstacle is that Magnetic Resonance imaging (MR) is contraindicated or hindered by significant artefacts in most cases with CIs. This study describes an automatic cochlear image registration and fusion method that aims to help radiologists and surgeons to process pre-and postoperative 3D multimodal imaging studies in cochlear implant (CI) patients.

Methods and findings: We propose a new registration method, Automatic Cochlea Image Registration (ACIR-v3), which uses a stochastic quasi-Newton optimiser with a mutual information metric to find 3D rigid transform parameters for registration of preoperative and postoperative CI imaging. The method was tested against a clinical cochlear imaging dataset that contains 131 multimodal 3D imaging studies of 41 CI patients with preoperative and postoperative images. The preoperative images were MR, Multidetector Computed Tomography (MDCT) or Cone Beam Computed Tomography (CBCT) while the postoperative were CBCT. The average root mean squared error of ACIR-v3 method was 0.41 mm with a standard deviation of 0.39 mm. The results were evaluated quantitatively using the mean squared error of two 3D landmarks located manually by two neuroradiology experts in each image and compared to other previously known registration methods, e.g. Fast Preconditioner Stochastic Gradient Descent, in terms of accuracy and speed.

Conclusions: Our method, ACIR-v3, produces high resolution images in the postoperative stage and allows for visualisation of the accurate anatomical details of the MRI with the absence of significant metallic artefacts. The method is implemented as an open-source plugin for 3D Slicer tool.

Accuracy of Patient Setup Positioning Using Surface-Guided Radiotherapy With Deformable Registration in Cases of Surface Deformation

Publication: J Appl Clin Med Phys. 2022 Mar;23(3):e13493. PMID: 35077004

Authors: Kadman B, Takemura A, Ito T, Okada N, Kojima H, Ueda S.

Institution: Division of Health Sciences, Graduate School of Medical Sciences, Pharmaceutical and Health Sciences, Kanazawa University, Japan.

Abstract: The Catalyst™ HD (C-RAD Positioning AB, Uppsala, Sweden) is surface-guided radiotherapy (SGRT) equipment that adopts a deformable model. The challenge in applying the SGRT system is accurately correcting the setup error using a deformable model when the body of the patient is deformed. This study evaluated the effect of breast deformation on the accuracy of the setup correction of the SGRT system. Physical breast phantoms were used to investigate the relationship between the mean deviation setup error obtained from the SGRT system and the breast deformation. Physical breast phantoms were used to simulate extension and shrinkage deformation (-30 to 30 mm) by changing breast pieces. 3D Slicer software was used to evaluate the deformation. The maximum deformations in X, Y, and Z directions were obtained as the differences between the original and deformed breasts. We collected the mean deviation setup error from the SGRT system by replacing the original breast part with the deformed breast part. The mean absolute difference of lateral, longitudinal, vertical, pitch, roll, and yaw, between the rigid and deformable registrations was 2.4 ± 1.7 mm, 1.3 ± 1.2 mm, 6.4 ± 5.2 mm, 2.5° ± 2.5°, 2.2° ± 2.4°, and 1.0° ± 1.0°, respectively. Deformation in the Y direction had the best correlation with the mean deviation translation error (R = 0.949) and rotation error (R = 0.832). As the magnitude of breast deformation increased, both mean deviation setup errors increased, and there was greater error in translation than in rotation. Large deformation of the breast surface affects the setup correction. Deformation in the Y direction most affects translation and rotation errors.

Quantitative Measurements of Esophageal Varices Using Computed Tomography for Prediction of Severe Varices and the Risk of Bleeding: A Preliminary Study

Publication: Insights Imaging. 2022 Mar 14;13(1):47. PMID: 35286491 | PDF

Authors: Wan S, He Y, Zhang X, Wei Y, Song B.

Institution: Department of Radiology, West China Hospital, Sichuan University, Chengdu, China.

Abstract: Background: We aimed to assess whether the quantitative parameters of esophageal varices (EV) based on computed tomography (CT) can noninvasively predict severe EV and the risk of esophageal variceal bleeding (EVB).

Methods: A total of 136 endoscopically confirmed EV patients were included in this retrospective study and were divided into a non-conspicuous (mild-to-moderate EV, n = 30) and a conspicuous EV group (severe EV, n = 106), a bleeding (n = 89) and a non-bleeding group (n = 47). EV grade (EVG), EV diameter (EVD), cross-sectional surface area (CSA), EV volume (EVV), spleen volume (SV), splenic vein (SNV), portal vein (PV), diameter of left gastric vein (DLGV), and the opening type of LGV were measured independently using 3D Slicer. Univariate and multivariate logistic analysis were used to determine the independent factors and the receiver operating characteristic (ROC) curves were performed to evaluate the diagnostic performance.

Results: The difference of EVG, EVD, CSA, EVV, DLGV, SNV between the conspicuous and non-conspicuous EV group were statistically significant (p < 0.05), area under the curves (AUCs) of them for predicting severe EV were 0.72, 0.772, 0.704, 0.768, 0.707, 0.65, with corresponding sensitivities of 70.3%, 63.5%, 50%, 74.3%, 52.7%, 48.6%, specificities of 71.4%, 85.7%, 100%, 71.4%, 81%, 81%, respectively. EVG, CSA (odds ratio 3.258, 95% CI 1.597-6.647; 1.029, 95% CI 1.008-1.050) were found to be independent predictive factors. However, there was no significant difference of the included indices between the bleeding and non-bleeding group (p > 0.05).

Conclusions: CT can be used as a noninvasive method to predict the severity of EV, which may reduce the invasive screening of endoscopy.

An Automatic Measurement System of Distal Femur Morphological Parameters Using 3D Slicer Software

Publication: Bone. 2022 Mar;156:116300. PMID: 34958998 | PDF

Authors: Chen Z, Wang Y, Li X, Wang K, Li Z, Yang P.

Institution: College of Computer Science, Xi'an University of Posts and Telecommunications, Shaanxi, China.

Abstract: In the field of joint surgery, the computer-aided design of knee prostheses suitable for the Chinese population requires a large quantity of anatomical knee data. In this study, we propose a new method that uses 3D Slicer software to automatically measure the morphological parameters of the distal femur. First, 141 femur samples were segmented from CT data to establish the femoral shape library. Next, balanced iterative reducing and clustering using hierarchies (BIRCH) combined with iterative closest point (ICP) and generalised procrustes analysis (GPA) were used to achieve fast registration of the femur samples. The statistical model was automatically calculated from the registered femur samples, and an orthopaedic surgeon marked the points on the statistical model. Finally, we developed an automatic measurement system using 3D Slicer software, and a deformable model matching method was applied to establish the point correspondence between the statistical model and the other samples. By matching points on the statistical model to corresponding points in other samples, we measured all other samples. We marked six points and measured eight parameters. We evaluated the performance of automatic matching by comparing the points marked manually with those matched automatically and verified the accuracy of the system by comparing the manual and automatic measurement results. The results indicated that the average error of the automatic matching points was 1.03 mm, and the average length error and average angle error measured automatically by the system were 0.37 mm and 0.63°, respectively. These errors were smaller than the intra-rater and inter-rater errors measured manually by two different surgeons, which showed that the accuracy of our automatic method was high. Taken together, this study established an accurate and automatic measurement system for the distal femur based on the secondary development of 3D Slicer software to assist orthopaedic surgeons in completing the measurements of big data and further promote the improved design of Chinese-specific knee prostheses.

Repeatability, Robustness, and Reproducibility of Texture Features on 3 Tesla Liver MRI

Publication: Clin Imaging. 2022 Mar;83:177-83. PMID: 35092926

Authors: Prabhu V, Gillingham N, Babb JS, Mali RD, Rusinek H, Bruno MT, Chandarana H.

Institution: Department of Radiology, NYU Langone Health, New York, NY, USA.

Abstract: Objective: Texture features are proposed for classification and prognostication, with lacking information about variability. We assessed 3 T liver MRI feature variability.

Methods: Five volunteers underwent standard 3 T MRI, and repeated with identical and altered parameters. Two readers placed regions of interest using 3D Slicer. Repeatability (between standard and repeat scan), robustness (between standard and parameter changed scan), and reproducibility (two reader variation) were computed using coefficient of variation (CV).

Results: 67%, 49%, and 61% of features had good-to-excellent (CV ≤ 10%) repeatability on ADC, T1, and T2, respectively, least frequently for first order (19-35%). 22%, 19%, and 21% of features had good-to-excellent robustness on ADC, T1, and T2, respectively. 52%, 35%, and 25% of feature measurements had good-to-excellent inter-reader reproducibility on ADC, T1, and T2, respectively, with highest good-to-excellent reproducibility for first order features on ADC/T1.

Conclusion: We demonstrated large variations in texture features on 3T liver MRI. Further study should evaluate methods to reduce variability.

Total Intracranial Volume as a Covariate for Predicting Prognosis in Patients With Primary Intracerebral Hemorrhage

Publication: Clin Neurol Neurosurg. 2022 Mar;214:107135. PMID: 35121234

Authors: Wang L, Liu C, Lu E, Zhang D, Zhang H, Xu X, Liu R, Yuan C, Sun J, Zhou Q, Chen X, Wang L, Yang G.

Institution: Department of Neurosurgery, The First Affiliated Hospital of Harbin Medical University, Harbin, China.

Abstract: Objectives: The initial hematoma volume is reliable and stable imaging predictor for the outcome of patients with intracerebral hemorrhage, and the total intracranial volume varies between patients. However, the role of total intracranial volume in predicting the prognosis of spontaneous intracerebral hemorrhage has not been previously addressed.

Methods: 782 patients with spontaneous intracerebral hemorrhage were selected in this retrospective cohort at the Neurosurgery Emergency Unit of The First Affiliated Hospital of Harbin Medical University. Due to missing CT images, initial CT exceeding 24 h, traumatic cerebral hemorrhage, and aneurysm, 145 patients were excluded and the remaining 637 patients were included in our analysis. Functional outcome was assessed using the modified Rankin Scale(mRS) and mortality at 3-months after spontaneous intracerebral hemorrhage. CT image datasets were calculated by 3D Slicer. The initial hematoma volume was normalized to the total intracranial volume to evaluate poor functional outcomes (mRS, 4-6) and mortality.

Results: The results demonstrated that normalized initial hematoma volume can be used as an indicator of poor functional outcome (mRS, 4-6) (AUCNrIHV=0.753, 95%-CI:0.710-0.795, p < 0.001), mortality (AUCNrIHV=0.808, 95%-CI:0.754-0.862, p < 0.001) and hematoma expansion (AUCNrIHV=0.690, 95%-CI:0.613-0.767, p < 0.001). Meanwhile, the initial hematoma volume in predicting poor functional outcome (AUCIHV=0.749, 95%-CI:0.707-0.792, p < 0.001), mortality (AUCIHV=0.816, 95%-CI: 0.763-0.870, p < 0.001) and hematoma expansion (AUCIHV=0.704, 95%-CI: 0.626-0.782, p < 0.001) was similar to the normalized initial hematoma volume.

Conclusions: The normalized initial hematoma volume has no apparent benefit in predicting the prognosis of patients with cerebral hemorrhage compared with initial hematoma volume.

3D-Slicer Software-Assisted Neuroendoscopic Surgery in the Treatment of Hypertensive Cerebral Hemorrhage

Publication: Comput Math Methods Med. 2022 Feb 18;2022:7156598. PMID: 35222690 | PDF

Authors: Liao R, Liu L, Song B, Wan X, Wang S, Xu J.

Institution: University of Ulsan Department of Oral and Maxillofacial Surgery, Chungang University Hospital, Seoul, South Korea.

Abstract: To explore the 3D Slicer software-assisted endoscopic treatment for patients with hypertensive cerebral hemorrhage.

Methods: A total of 120 patients with hypertensive cerebral hemorrhage were selected and randomly divided into control group and 3D Slicer group with 60 cases each. Patients in the control group underwent traditional imaging positioning craniotomy, and patients in the 3D Slicer group underwent 3D Slicer followed by precision puncture treatment. In this paper, we evaluate the hematoma clearance rate, nerve function, ability of daily living, complication rate, and prognosis.

Results: The 3D Slicer group is better than the control group in various indicators. Compared with the control group, the 3D Slicer group has lower complications, slightly higher hematoma clearance rate, and better recovery of nerve function and daily living ability before and after surgery. The incidence of poor prognosis is low.

Conclusion: The 3D Slicer software-assisted endoscopic treatment for patients with hypertensive intracerebral hemorrhage has a better hematoma clearance effect, which is beneficial to the patient's early recovery and reduces the damage to the brain nerve of the patient.

FreeSurfer and 3D Slicer-Assisted SEEG Implantation for Drug-Resistant Epilepsy

Publication: Front Neurorobot. 2022 Feb 28;16:848746. PMID: 35295674 | PDF

Authors: Liu Q, Wang J, Wang C, Wei F, Zhang C, Wei H, Ye X, Xu J.

Institution: Department of Neurosurgery, Clinical Neuroscience Center Comprehensive Epilepsy Unit, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.

Abstract: Objective: Our study aimed to develop an approach to improve the speed and resolution of cerebral-hemisphere and lesion modeling and evaluate the advantages and disadvantages of robot-assisted surgical planning software.

Methods: We applied both conventional robot planning software (method 1) and open-source auxiliary software (FreeSurfer and 3D Slicer; method 2) to model the brain and lesions in 19 patients with drug-resistant epilepsy. The patients' mean age at implantation was 21.4 years (range, 6-52 years). Each patient received an average of 12 electrodes (range, 9-16) between May and November 2021. The electrode-implantation plan was designed based on the models established using the two methods. We statistically analyzed and compared the duration of designing the models and planning the implantation using these two methods and performed the surgeries with the implantation plan designed using the auxiliary software.

Results: A significantly longer time was needed to reconstruct a cerebral-hemisphere model using method 1 (mean, 206 s) than using method 2 (mean, 20 s) (p < 0.05). Both methods identified a mean of 1.4 lesions (range, 1-5) in each patient. Overall, using method 1 required longer (mean, 130 s; range, 48-436) than using method 2 (mean, 68.1 s; range, 50-104; p < 0.05). In addition, the clarity of the model based on method 1 was lower than that based on method 2. To devise an electrode-implantation plan, it took 9.1-25.5 min (mean, 16) and 6.6-14.8 min (mean, 10.2) based on methods 1 and 2, respectively (p < 0.05). The average target point error of 231 electrodes amounted to 1.90 mm ± 0.37 mm (range, 0.33-3.61 mm). The average entry point error was 0.89 ± 0.26 mm (range, 0.17-1.67 mm). None of the patients presented with intracranial hemorrhage or infection, and no other serious complications were observed.

Conclusions: FreeSurfer and 3D Slicer-assisted SEEG implantation is an excellent approach to enhance modeling speed and resolution, shorten the electrode-implantation planning time, and boost the efficiency of clinical work. These well-known, trusted open-source programs do not have explicitly restricted licenses. These tools, therefore, seem well suited for clinical-research applications under the premise of approval by an ethics committee, informed consent of the patient, and clinical judgment of the surgeon.

SegmentGeometry: A Tool for Measuring Second Moment of Area in 3D Slicer

Publication: Integr Org Biol. 2022 Feb 28;4(1):obac009. PMID: 35291672 | PDF

Authors: Huie JM, Summers AP, Kawano SM.

Institution: Department of Biological Sciences, George Washington University, Washington, DC, USA.

Abstract: Second moment of area is a measure of how well the cross-section of a beam will resist bending because of its shape. Many have used second moment of area to investigate the mechanical adaptations of biological structures from stingray jaws to animal limb bones. In this context it is important to acknowledge the assumptions of beam theory, in which second moment of area plays a key role, if reasonable results are desired. For example, to minimize shear the structure should be at least 10 times longer than it is wide and deflection should be minimal. Analyzing the internal geometry of biological structures has never been easier or more accessible given the wide, and growing availability of micro-CT scans. Here, we offer a guide on the care that needs to be taken when interpreting second moment of area, and present open-access, open-source software that can process hundreds if not thousands of structures in a short time frame. SegmentGeometry, an extension for the open-source imaging platform 3D Slicer, iterates slice-by-slice through 3D structures to calculate second moment of area and other cross-sectional properties. We analyzed 2 case studies to demonstrate the power of this tool and to highlight interpretations that can be gleaned from second moment of area. Second moment of area is just one part of the Euler-Bernoulli beam theory and considering the full equation would greatly increase the number and diversity of questions that can be answered.

Decreased Functional Connectivities of Low-Degree Level Rich Club Organization and Caudate in Post-stroke Cognitive Impairment Based on Resting-State fMRI and Radiomics Features

Publication: Front Neurosci. 2022 Feb 16;15:796530. PMID: 35250435 | PDF

Authors: Miao G, Rao B, Wang S, Fang P, Chen Z, Chen L, Zhang X, Zheng J, Xu H, Liao W.

Institution: Department of Rehabilitation Medicine, Zhongnan Hospital of Wuhan University, Wuhan, China.

Abstract: Background: Stroke is an important cause of cognitive impairment. Rich club organization, a highly interconnected network brain core region, is closely related to cognition. We hypothesized that the disturbance of rich club organization exists in patients with post-stroke cognitive impairment (PSCI).

Methods: We collected data on resting-state functional magnetic resonance imaging (rs-fMRI) with 21 healthy controls (HC), 16 hemorrhagic stroke (hPSCI), and 21 infarct stroke (iPSCI). 3D shape features and first-order statistics of stroke lesions were extracted using 3D Slicer software. Additionally, we assessed cognitive function using the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE).

Results: Normalized rich club coefficients were higher in hPSCI and iPSCI than HC at low-degree k-levels (k = 1-8 in iPSCI, k = 2-8 in hPSCI). Feeder and local connections were significantly decreased in PSCI patients versus HC, mainly distributed in salience network (SN), default-mode network (DMN), cerebellum network (CN), and orbitofrontal cortex (ORB), especially involving the right and left caudate with changed nodal efficiency. The feeder and local connections of significantly between-group difference were positively related to MMSE and MoCA scores, primarily distributed in the sensorimotor network (SMN) and visual network (VN) in hPSCI, SN, and DMN in iPSCI. Additionally, decreased local connections and low-degree ϕnorm(k) were correlated to 3D shape features and first-order statistics of stroke lesions.

Conclusion: This study reveals the disrupted low-degree level rich club organization and relatively preserved functional core network in PSCI patients. Decreased feeder and local connections in cognition-related networks (DMN, SN, CN, and ORB), particularly involving the caudate nucleus, may offer insight into pathological mechanism of PSCI patients. The shape and signal features of stroke lesions may provide an essential clue for the damage of functional connectivity and the whole brain networks.

Morphological Changes of the Root Apex in Anterior Teeth With Periapical Periodontitis: An In-Vivo Study

Publication: BMC Oral Health. 2022 Feb 5;22(1):31. PMID: 35120518 | PDF

Authors: Zhang CC, Liu YJ, Yang WD, Zhang QN, Zha MZ, Wen SH, Wang Q.

Institution: Department of Endodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing City, China.

Abstract: Introduction: The aim was to analyze the morphological changes of root apex in anterior teeth with periapical periodontitis.

Methods: 32 untreated anterior teeth with periapical periodontitis were enrolled, compared with the healthy contralateral teeth. Two-dimensional measurement of Cone-beam computed tomography was used to determine the location and measure diameter of the apical constriction according to Schell's methods. An open-source software, 3D Slicer was used to reconstruct the teeth. The apical constriction form was analysis according to Schell's topography. The distances of apical constriction to apical foramen and anatomical apex were measured respectively.

Results: The difference value between buccolingual and mesiodistal diameter was (0.06 ± 0.09) mm and (0.04 ± 0.04) mm in periapical periodontitis and controls (p < 0.05). The mean distance between apical constriction and anatomical apex was significantly shorter in periapical periodontitis than controls, so was the mean distance of apical constriction to apical foramen. The most common form of apical constriction was flaring (65.6%) in periapical periodontitis.

Conclusions: The anterior teeth with periapical periodontitis had shorter distances of apical constriction to anatomical apex and apical foramen, bigger disparities between the diameters of buccolingual and mesiodistal, and higher proportion of flaring apical constriction.

Volumetric White Matter Hyperintensity Ranges Correspond to Fazekas Scores on Brain MRI

Publication: J Stroke Cerebrovasc Dis. 2022 Feb 11;31(4):106333. PMID: 35158149

Authors: Andere A, Jindal G, Molino J, Collins S, Merck D, Burton T, Stretz C, Yaghi S, Sacchetti DC, Jamal SE, Reznik ME, Furie K, Cutting S.

Institution: Department of Neurology, Brown University, Providence, RI, USA.

Abstract: Introduction: White matter hyperintensity (WMH) is an abnormal T2 signal in the deep and subcortical white matter visualized on MRI associated with hypertension, cerebrovascular disease, and aging. The Fazekas (Fz) scoring system is a commonly used qualitative tool to assess the severity of WMH. While studies have compared Fazekas scores to other scoring methods, the comparison of Fazekas scores and volume of WMH using current semiautomated volumetric techniques has not been studied.

Methods: We reviewed MRI studies acquired at our institution between 2015 and 2017. Relative WMH was scored by one author trained in Fazekas scoring. A board certified neuroradiologist scored them independently for confirmation. Manual segmentations of WMH were completed using 3D Slicer v.4.9. A 3D model was formed to quantify WMH in milliliters (mL). ANOVA tests were performed to determine the association of Fazekas scores with corresponding WMH volumes.

Results: Among the 198 patients in our study, WMH were visualized in 163 (Fz1: n=66; Fz2: n=49; Fz3: n=48). WMH volumes significantly differed according to Fazekas score (F = 141.1, p<0.001), with increasing WMHV associated with higher Fazekas scores: Fz1, range 0.1-8.3 mL (mean 3.7, SD 2.3); Fz2, range 6.0-17.7 mL (mean 10.8, SD 3.1); Fz3, range 14.2-77.2 mL (mean 35.2, SD 17.9); and Fz3 (excluding 11 outliers above 50 mL), 14.2-47.0 mL (mean 27.1, SD 8.9).

Conclusion: Fazekas scores correspond with distinct ranges of WMH volume with relatively little overlap, but scores based on volumes are more efficacious. A modified Fazekas from 0-4 should be considered.

A Radiomics Model Based on DCE-MRI and DWI May Improve the Prediction of Estimating IDH1 Mutation and Angiogenesis in Gliomas

Publication: Eur J Radiol. 2022 Feb;147:110141. PMID: 34995947

Authors: Wang J, Hu Y, Zhou X, Bao S, Chen Y, Ge M, Jia Z.

Institution: Department of Medical Imaging, Affiliated Hospital of Nantong University, Nantong, China.

Abstract: Purpose: To investigate the value of a radiomics model based on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion weighted imaging (DWI) in estimating isocitrate dehydrogenase 1 (IDH1) mutation and angiogenesis in gliomas.

Method: One hundred glioma patients with DCE-MRI and DWI were enrolled in this study (training and validation groups with a ratio of 7:3). The IDH1 genotypes and expression of vascular endothelial growth factor (VEGF) in gliomas were assessed by immunohistochemistry. Radiomics features were extracted by an open source software 3D Slicer and reduced using Least absolute shrinkage and selection operator (Lasso). The support vector machine (SVM) model was developed based on the most useful predictive radiomics features. The conventional model was built by the selected clinical and morphological features. Finally, a combined model including radiomics signature, age and enhancement degree was established. Receiver operator characteristic (ROC) curve was implemented to assess the diagnostic performance of the three models.

Results: For IDH1 mutation, the combined model achieved the highest area under curve (AUC) in comparison with the SVM and conventional models (training group, AUC = 0.967, 0.939 and 0.906; validation group, AUC = 0.909, 0.880 and 0.842). Furthermore, the SVM model showed good diagnostic performance in estimating gliomas VEGF expression (validation group, AUC = 0.919).

Conclusions: The radiomics model based on DCE-MRI and DWI can have a considerable effect on the evaluation of IDH1 mutation and angiogenesis in gliomas.

The Role of Pre-therapeutic 18F-FDG PET/CT in Pediatric Hemophagocytic Lymphohistiocytosis With Epstein-Barr Virus Infection

Publication: Front Med (Lausanne). 2022 Jan 21;8:836438. PMID: 35127776 | PDF

Authors: Lu X, Wei A, Yang X, Liu J, Li S, Kan Y, Wang W, Wang T, Zhang R, Yang J.

Institution: Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.

Abstract: Objective: To evaluate the role of pre-therapeutic 18F-FDG PET/CT in pediatric hemophagocytic lymphohistiocytosis (HLH) with Epstein-Barr virus (EBV) infection.

Methods: This retrospective study included 29 HLH children (1-16 years) with EBV infection, who underwent pre-therapeutic 18F-FDG PET/CT from July 2018 to November 2020. Pathology results were considered as the reference standard. These patients were divided into two groups: EBV-induced malignancy-associated HLH (M-HLH, N = 9) and EBV-induced non-malignancy-associated HLH (NM-HLH, N = 20). The regions of interest (ROIs) of the liver, spleen (Sp), bone marrow (BM), lymph nodes (LN), hypermetabolic lesions, liver background (LiBG), and mediastinum (M) were drawn with software 3D Slicer. The volumetric and metabolic parameters, including maximum standard uptake value (SUVmax), metabolic tumor volume, and total lesion glycolysis of these ROIs, clinical parameters, and laboratory parameters were compared between the two groups. The efficiency of the above parameters in predicting the treatment response and overall survival (OS) was analyzed.

Results: Receiver operating characteristic curve analysis indicated that SUVmax-lesions and SUVmax-LN/M (AUC = 0.822, 0.819, cut-off = 6.04, 5.74, respectively) performed better in differentiating M-HLH from NM-HLH. It had the best diagnostic performance when age was added with the SUVmax-LN/M (AUC = 0.933, sensitivity = 100%, specificity = 85.0%). The presence of extranodal hypermetabolic lesions in multiple organs indicated the M-HLH (P = 0.022). Older age, higher SUVmax-LN and SUVmax-lesions, and the presence of serous effusion were associated with poorer treatment response at the 2nd and 4th week (not reaching partial remission). Multivariate analysis showed that SUVmax-lesions > 7.66 and SUVmax-Sp/LiBG > 2.01 were independent prognostic factors for overall survival (P = 0.025, 0.036, respectively).

Conclusions: 18F-FDG PET/CT could be a valuable technique for identifying the underlying malignancy and predicting prognosis in pediatric HLH with EBV infection. M-HLH could be considered when SUVmax-lesions > 6.04, SUVmax-LN/M > 5.74, and the presence of extranodal hypermetabolic lesions in multiple organs on 18F-FDG PET/CT. SUVmax-lesions and SUVmax-Sp/LiBG might be independent prognostic factors for OS.

A Preoperative MRI-Based Radiomics-Clinicopathological Classifier to Predict the Recurrence of Pituitary Macroadenoma Within 5 Years

Publication: Front Neurol. 2022 Jan 5;12:780628. PMID: 35069413 | PDF

Authors: Zhang Y, Luo Y, Kong X, Wan T, Long Y, Ma J.

Institution: Department of Radiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Abstract: To investigate the ability of a MRI-based radiomics-clinicopathological model to predict pituitary macroadenoma (PMA) recurrence within 5 years. Materials and Methods: We recruited 74 recurrent and 94 non-recurrent subjects, following first surgery with 5-year follow-up data. Univariate and multivariate analyses were conducted to identify independent clinicopathological risk factors. Two independent and blinded neuroradiologists used 3D Slicer software to manually delineate whole tumors using preoperative axial contrast-enhanced T1WI (CE-T1WI) images. 3D Slicer was then used to extract radiomics features from segmented tumors. Dimensionality reduction was carried out by the least absolute shrinkage and selection operator (LASSO). Two multilayer perceptron (MLP) models were established, including independent clinicopathological risk factors (Model 1) and a combination of screened radiomics features and independent clinicopathological markers (Model 2). The predictive performance of these models was evaluated by receiver operator characteristic (ROC) curve analysis. Results: In total, 1,130 features were identified, and 4 of these were selected by LASSO. In the test set, the area under the curve (AUC) of Model 2 was superior to Model 1 {0.783, [95% confidence interval (CI): 0.718-.860] vs. 0.739, (95% CI: 0.665-0.818)}. Model 2 also yielded the higher accuracy (0.808 vs. 0.692), sensitivity (0.826 vs. 0.652), and specificity (0.793 vs. 0.724) than Model 1. Conclusions: The integrated classifier was superior to a clinical classifier and may facilitate the prediction of individualized prognosis and therapy.

Spatial Omics: Navigating to the Golden Era of Cancer Research

Publication: Clin Transl Med. 2022 Jan;12(1):e696. PMID: 35040595 | PDF

Authors: Wu Y, Cheng Y, Wang X, Fan J, Gao Q.

Institution: Center for Tumor Diagnosis & Therapy and Department of Cancer Center, Zhongshan Hospital, Fudan University, Shanghai, China.

Abstract: The idea that tumour microenvironment (TME) is organised in a spatial manner will not surprise many cancer biologists; however, systematically capturing spatial architecture of TME is still not possible until recent decade. The past five years have witnessed a boom in the research of high-throughput spatial techniques and algorithms to delineate TME at an unprecedented level. Here, we review the technological progress of spatial omics and how advanced computation methods boost multi-modal spatial data analysis. Then, we discussed the potential clinical translations of spatial omics research in precision oncology, and proposed a transfer of spatial ecological principles to cancer biology in spatial data interpretation. So far, spatial omics is placing us in the golden age of spatial cancer research. Further development and application of spatial omics may lead to a comprehensive decoding of the TME ecosystem and bring the current spatiotemporal molecular medical research into an entirely new paradigm.

"Computational strategies originally designed for radiomics, such as 3D Slicer, are expected to reconstruct the spatial molecular organization."

WHO Grade Loses Its Prognostic Value in Molecularly Defined Diffuse Lower-Grade Gliomas

Publication: Front Oncol. 2022 Jan 10;11:803975. PMID: 35083156 | PDF

Authors: Carstam L, Corell A, Smits A, Dénes A, Barchéus H, Modin K, Sjögren H, Ferreyra Vega S, Bontell TO, Carén H, Jakola AS.

Institution: Department of Neurosurgery, Sahlgrenska University Hospital, Gothenburg, Sweden.

Abstract: Background: While molecular insights to diffuse lower-grade glioma (dLGG) have improved the basis for prognostication, most established clinical prognostic factors come from the pre-molecular era. For instance, WHO grade as a predictor for survival in dLGG with isocitrate dehydrogenase (IDH) mutation has recently been questioned. We studied the prognostic role of WHO grade in molecularly defined subgroups and evaluated earlier used prognostic factors in the current molecular setting.

Material and methods: A total of 253 adults with morphological dLGG, consecutively included between 2007 and 2018, were assessed. IDH mutations, codeletion of chromosomal arms 1p/19q, and cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) deletions were analyzed.

Results: There was no survival benefit for patients with WHO grade 2 over grade 3 IDH-mut dLGG after exclusion of tumors with known CDKN2A/B homozygous deletion (n=157) (log-rank p=0.97). This was true also after stratification for oncological postoperative treatment and when astrocytomas and oligodendrogliomas were analyzed separately. In IDH-mut astrocytomas, residual tumor volume after surgery was an independent prognostic factor for survival (HR 1.02; 95% CI 1.01-1.03; p=0.003), but not in oligodendrogliomas (HR 1.02; 95% CI 1.00-1.03; p=0.15). Preoperative tumor size was an independent predictor in both astrocytomas (HR 1.03; 95% CI 1.00-1.05; p=0.02) and oligodendrogliomas (HR 1.05; 95% CI 1.01-1.09; p=0.01). Age was not a significant prognostic factor in multivariable analyses (astrocytomas p=0.64, oligodendrogliomas p=0.08).

Conclusion: Our findings suggest that WHO grade is not a robust prognostic factor in molecularly well-defined dLGG. Preoperative tumor size remained a prognostic factor in both IDH-mut astrocytomas and oligodendrogliomas in our cohort, whereas residual tumor volume predicted prognosis in IDH-mut astrocytomas only. The age cutoffs for determining high risk in patients with IDH-mut dLGG from the pre-molecular era are not supported by our results.

Keywords: CDKN2A/B deletion; IDH-mut; WHO grade; astrocytoma; extent of resection; lower-grade glioma; oligodendroglioma; prognostic factors.

"The volume of residual tumor after surgery was determined by tumor volume segmentation. The tumor volume was evaluated by semi-automatic segmentation performed with the open-source software 3D Slicer, v.4.6.2 or newer."

A Baboon Brain Atlas for Magnetic Resonance Imaging and Positron Emission Tomography Image Analysis

Publication: Front Neuroanat. 2022 Jan 14;15:778769. PMID: 35095430 | PDF

Authors: Agaronyan A, Syed R, Kim R, Hsu CH, Love SA, Hooker JM, Reid AE, Wang PC, Ishibashi N, Kang Y, Tu TW.

Institution: Center for Neuroscience Research, Children's National Hospital, Washington D.C., USA.

Abstract: The olive baboon (Papio anubis) is phylogenetically proximal to humans. Investigation into the baboon brain has shed light on the function and organization of the human brain, as well as on the mechanistic insights of neurological disorders such as Alzheimer's and Parkinson's. Non-invasive brain imaging, including positron emission tomography (PET) and magnetic resonance imaging (MRI), are the primary outcome measures frequently used in baboon studies. PET functional imaging has long been used to study cerebral metabolic processes, though it lacks clear and reliable anatomical information. In contrast, MRI provides a clear definition of soft tissue with high resolution and contrast to distinguish brain pathology and anatomy, but lacks specific markers of neuroreceptors and/or neurometabolites. There is a need to create a brain atlas that combines the anatomical and functional/neurochemical data independently available from MRI and PET. For this purpose, a three-dimensional atlas of the olive baboon brain was developed to enable multimodal imaging analysis. The atlas was created on a population-representative template encompassing 89 baboon brains. The atlas defines 24 brain regions, including the thalamus, cerebral cortex, putamen, corpus callosum, and insula. The atlas was evaluated with four MRI images and 20 PET images employing the radiotracers for [11C]benzamide, [11C]metergoline, [18F]FAHA, and [11C]rolipram, with and without structural aids like [18F]fluorodeoxyglucose images. The atlas-based analysis pipeline includes automated segmentation, registration, quantification of region volume, the volume of distribution, and standardized uptake value. Results showed that, in comparison to PET analysis utilizing the "gold standard" manual quantification by neuroscientists, the performance of the atlas-based analysis was at >80 and >70% agreement for MRI and PET, respectively. The atlas can serve as a foundation for further refinement, and incorporation into a high-throughput workflow of baboon PET and MRI data. The new atlas is freely available on the Figshare online repository (https://doi.org/10.6084/m9.figshare.16663339), and the template images are available from neuroImaging tools & resources collaboratory (NITRC) (https://www.nitrc.org/projects/haiko89/).

"Each PET image was registered to the atlas by 3D Slicer’s landmark registration tool "

SPHARM-PDM Based Image Preprocessing Pipeline for Quantitative Morphometric Analysis (QMA) for in Situ Joint Assessment in Rabbit and Rat Models

Publication: Sci Rep. 2022 Jan 21;12(1):1113. PMID: 35064147 | PDF

Authors: Durongbhan P, Davey CE, Stok KS.

Institution: Department of Biomedical Engineering, The University of Melbourne, Australia.

Abstract: The accessibility of quantitative measurements of joint morphometry depends on appropriate tibial alignment and volume of interest (VOI) selection of joint compartments; often a challenging and time-consuming manual task. In this work, we developed a novel automatic, efficient, and model-invariant image preprocessing pipeline that allows for highly reproducible 3D quantitative morphometric analysis (QMA) of the joint. The pipeline addresses the problem by deploying two modules: an alignment module and a subdivision module. Alignment is achieved by representing the tibia in its basic form using lower degree spherical harmonic basis functions and aligning using principal component analysis. The second module subdivides the joint into lateral and medial VOIs via a water shedding approach based on persistence homology. Multiple repeated micro-computed tomography scans of small (rat) and medium (rabbit) animal knees were processed using the pipeline to demonstrate model invariance. Existing QMA was performed to evaluate the pipeline's ability to generate reproducible measurements. Intraclass correlation coefficient and mean-normalised root-mean-squared error of more than 0.75 and lower than 9.5%, respectively, were achieved for joint centre of mass, joint contact area under virtual loading, joint space width, and joint space volume. Processing time and technical requirements were reduced compared to manual processing in previous studies.

"SPHARM processing, statistical shape analysis module in 3D Slicer)"

Clinical Evaluation of 3D Printed Nano-Porous Hydroxyapatite Bone Graft for Alveolar Ridge Preservation: A Randomized Controlled Trial

Publication: J Dent Sci. 2022 Jan;17(1):194-203. PMID: 35028038 | PDF

Authors: Kijartorn P, Wongpairojpanich J, Thammarakcharoen F, Suwanprateeb J, Buranawat B.

Institution: Department of Periodontology and Implantology, Faculty of Dentistry, Thammasat University, Pathum Thani, Thailand.

Abstract: Background/purpose: Ridge resorption after tooth extraction may result in inadequate bone volume and unfavorable ridge architecture for ideal implant placement. The use of bone substitutes has been advocated to fill extraction sites and to enhance primary implant stability. This study was made to evaluate the clinical efficacy of novel 3D printed nano-porous hydroxyapatite (3DP HA, test group) in comparison to nano-crystalline bone graft (NanoBone®, control group) in alveolar ridge preservation prior to implant placement.

Materials and methods: Thirty patients were randomized into two groups following tooth extraction. All extracted sockets were filled with 3DP HA or NanoBone® and covered with a non-resorbable membrane. After four months, cone-beam computed tomography (CBCT) and intraoral scanner were used to measure dimensional changes of bone and soft tissue surface. Bone core specimens were harvested for histological analysis during implant osteotomy. Implant stability was assessed using a modified damping capacity analysis.

Results: At four months postoperatively, dimensional changes in soft tissue surface resorption were less in the test group than in the control group; however, alveolar bone resorption was the same in both groups. Histological analysis revealed new bone formation, residual graft and fibrous connective tissue in both groups. The average primary implant stability (IST) value for both groups was approximately 70. There was no statistically significant difference in all parameters between two groups (p > 0.05).

Conclusion: 3DP HA could potentially be used as an alternative bone graft material for alveolar ridge preservation.

"To measure the alveolar bone changes, two DICOM files acquired from CBCT from two time points were segmented and reconstructed into 3D STL image files by using 3D Slicer software v.4.10.1."

High-Resolution MRI of the Human Palatine Tonsil and Its Schematic Anatomic 3D Reconstruction

Publication: J Anat. 2022 Jan;240(1):166-71. PMID: 34342906 | PDF

Authors: Herrmann KH, Hoffmann F, Ernst G, Pertzborn D, Pelzel D, Geißler K, Guntinas-Lichius O, Reichenbach JR, von Eggeling F.

Institution: Medical Physics Group, Institute for Diagnostic and Interventional Radiology, Jena University Hospital, Jena, Germany.

Abstract: The palatine tonsils form an important part of the human immune system. Together with the other lymphoid tonsils of Waldeyer's tonsillar ring, they act as the first line of defense against ingested or inhaled pathogens. Although histologically stained sections of the palatine tonsil are widely available, they represent the tissue only in two dimensions and do not provide reference to three-dimensional space. Such a representation of a tonsillar specimen based on imaging data as a 3D anatomical reconstruction is lacking both in scientific publications and especially in textbooks. As a first step in this direction, the objective of the present work was to image a resected tonsil specimen with high spatial resolution in a 9.4 T small-bore preclinical MRI and to combine these data with data from the completely sectioned and H&E stained same palatine tonsil. Based on the information from both image modalities, a 3D anatomical sketch was drawn by a scientific graphic artist. In perspective, such studies could help to overcome the difficulty of capturing the spatial extent and arrangement of anatomical structures from 2D images and to establish a link between three-dimensional anatomical preparations and two-dimensional sections or illustrations, as they have been found so far in common textbooks and anatomical atlases.

"3D model was assembled using the free software tool, 3D Slicer"

The Effects of Cranial Orientation on Forensic Frontal Sinus Identification as Assessed by Outline Analyses

Publication: Clin Transl Med. 2022 Jan;12(1):e696. PMID: 35053060 | PDF

Authors: Butaric LN, Richman A, Garvin HM.

Institution: Department of Anatomy, Des Moines University, 3200 Grand Avenue, Des Moines, IA, USA.

Abstract: The utility of frontal sinuses for personal identification is widely recognized, but potential factors affecting its reliability remain uncertain. Deviations in cranial position between antemortem and postmortem radiographs may affect sinus appearance. This study investigates how slight deviations in orientations affect sinus size and outline shape and potentially impact identification. Frontal sinus models were created from CT scans of 21 individuals and digitally oriented to represent three clinically relevant radiographic views. From each standard view, model orientations were deviated at 5° intervals in horizontal, vertical, and diagonal (e.g., left-up) directions (27 orientations per individual). For each orientation, sinus dimensions were obtained, and outline shape was assessed by elliptical Fourier analyses and principal component (PC) analyses. Wilcoxon sign rank tests indicated that sinus breadth remained relatively stable (p > 0.05), while sinus height was significantly affected with vertical deviations (p < 0.006). Mann-Whitney U tests on Euclidean distances from the PC scores indicated consistently lower intra- versus inter-individual distances (p < 0.05). Two of the three orientations maintained perfect (100%) outline identification matches, while the third had a 98% match rate. Smaller and/or discontinuous sinuses were most problematic, and although match rates are high, practitioners should be aware of possible alterations in sinus variables when conducting frontal sinus identifications.

"The associated frontal sinus and cranial models for each individual were imported into the program 3D Slicer."

Phenotyping Type 2 Diabetes in Terms of Myocardial Insulin Resistance and Its Potential Cardiovascular Consequences: A New Strategy Based on 18 F-FDG PET/CT

Publication: J Pers Med. 2022 Jan 2;12(1):30. PMID: 35055345 | PDF

Authors: Herance JR, Simó R, Velasquez MA, Paun B, García-Leon D, Aparicio C, Marés R, Simó-Servat O, Castell-Conesa J, Hernández C, Aguadé-Bruix S.

Institution: Medical Molecular Imaging Research Group, Nuclear Medicine Department, Vall d'Hebron Research Institute (VHIR), Vall d'Hebron University Hospital, Autonomous University Barcelona, Barcelona, Spain.

Abstract: Background: Systemic insulin resistance is generally postulated as an independent risk factor of cardiovascular events in type 2 diabetes (T2D). However, the role of myocardial insulin resistance (mIR) remains to be clarified.

Methods: Two 18F-FDG PET/CT scans were performed on forty-three T2D patients at baseline and after hyperinsulinemic-euglycemic clamp (HEC). Myocardial insulin sensitivity (mIS) was determined by measuring the increment in myocardial 18F-FDG uptake after HEC. Coronary artery calcium scoring (CACs) and myocardial radiodensity (mRD) were assessed by CT.

Results: After HEC, seventeen patients exhibited a strikingly enhancement of myocardial 18F-FDG uptake and twenty-six a marginal increase, thus revealing mIS and mIR, respectively. Patients with mIR showed higher mRD (HU: 38.95 [33.81-44.06] vs. 30.82 [21.48-38.02]; p = 0.03) and CACs > 400 (AU: 52% vs. 29%; p = 0.002) than patients with mIS. In addition, HOMA-IR and mIS only showed a correlation in those patients with mIR.

Conclusions: 18F-FDG PET combined with HEC is a reliable method for identifying patients with mIR. This subgroup of patients was found to be specifically at high risk of developing cardiovascular events and showed myocardial structural changes. Moreover, the gold-standard HOMA-IR index was only associated with mIR in this subgroup of patients. Our results open up a new avenue for stratifying patients with cardiovascular risk in T2D.

"All acquired 18F-FDG PET images in DICOM format were first SUVbw normalized using the PET DICOM Extension available in 3D Slicer."

Developing Virtual Reality Head Mounted Display (HMD) Set-Up for Thoracoscopic Surgery of Complex Congenital Lung MalFormations in Children

Publication: Children (Basel). 2022 Jan 3;9(1):50. PMID: 35053675 | PDF

Authors: Pelizzo G, Costanzo S, Roveri M, Lanfranchi G, Vertemati M, Milani P, Zuccotti G, Cassin S, Panfili S, Rizzetto F, Campari A, Camporesi A, Calcaterra V.

Institution: Pediatric Surgery Department, "Vittore Buzzi" Children's Hospital, Milan, Italy.

Abstract: Video assisted thoracoscopic surgery (VATS) has been adopted in pediatric age for the treatment of congenital lung malformations (CLM). The success of VATS in pediatrics largely depends on the surgeon's skill ability to understand the airways, vascular system and lung parenchyma anatomy in CLM. In the last years, virtual reality (VR) and 3-dimensional (3D) printing of organ models and VR head mounted display (HMD) technologies have been introduced for completion of preoperative planning in adult patients. To date no reports about the use of VR HMD technologies in a pediatric setting are available. The aim of this report is to introduce a VR HMD model in VATS procedure to improve the quality of care in children with CLM. VR HMD set-up for planning thoracoscopic surgery was performed in a series of pediatric patients with diagnosis of CLM. The preoperative VR HMD evaluation allowed a navigation into the malformation with the aim to explore, interact, and make the surgeon more confident and skilled to answer to the traps. A development of surgical simulations models and teaching program dedicated to education and training in pediatric VATS is suitable among the pediatric surgery community. Further studies should demonstrate all the benefits of such technology in pediatric patients submitted to VATS procedure.

"CT images were then exported into DICOM files and loaded into 3D Slicer."

Dynamic Contrast-Enhanced Magnetic Resonance Imaging for the Prediction of Monoclonal Antibody Tumor Disposition

Publication: Int J Mol Sci. 2022 Jan 8;23(2):679. PMID: 35054865 | PDF

Authors: Bordeau BM, Polli JR, Schweser F, Grimm HP, Richter WF, Balthasar JP.

Institution: Department of Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA.

Abstract: The prediction of monoclonal antibody (mAb) disposition within solid tumors for individual patients is difficult due to inter-patient variability in tumor physiology. Improved a priori prediction of mAb pharmacokinetics in tumors may facilitate the development of patient-specific dosing protocols and facilitate improved selection of patients for treatment with anti-cancer mAb. Here, we report the use of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), with tumor penetration of the contrast agent gadobutrol used as a surrogate, to improve physiologically based pharmacokinetic model (PBPK) predictions of cetuximab pharmacokinetics in epidermal growth factor receptor (EGFR) positive xenografts. In the initial investigations, mice bearing Panc-1, NCI-N87, and LS174T xenografts underwent DCE-MRI imaging with the contrast agent gadobutrol, followed by intravenous dosing of an 125Iodine-labeled, non-binding mAb (8C2). Tumor concentrations of 8C2 were determined following the euthanasia of mice (3 h-6 days after 8C2 dosing). Potential predictor relationships between DCE-MRI kinetic parameters and 8C2 PBPK parameters were evaluated through covariate modeling. The addition of the DCE-MRI parameter Ktrans alone or Ktrans in combination with the DCE-MRI parameter Vp on the PBPK parameters for tumor blood flow (QTU) and tumor vasculature permeability (σTUV) led to the most significant improvement in the characterization of 8C2 pharmacokinetics in individual tumors. To test the utility of the DCE-MRI covariates on a priori prediction of the disposition of mAb with high-affinity tumor binding, a second group of tumor-bearing mice underwent DCE-MRI imaging with gadobutrol, followed by the administration of 125 Iodine-labeled cetuximab (a high-affinity anti-EGFR mAb). The MRI-PBPK covariate relationships, which were established with the untargeted antibody 8C2, were implemented into the PBPK model with considerations for EGFR expression and cetuximab-EGFR interaction to predict the disposition of cetuximab in individual tumors (a priori). The incorporation of the Ktrans MRI parameter as a covariate on the PBPK parameters QTU and σTUV decreased the PBPK model prediction error for cetuximab tumor pharmacokinetics from 223.71 to 65.02%. DCE-MRI may be a useful clinical tool in improving the prediction of antibody pharmacokinetics in solid tumors. Further studies are warranted to evaluate the utility of the DCE-MRI approach to additional mAbs and additional drug modalities.

"Dynamic contrast-enhanced scans were opened in 3D Slicer, and tumor regions were defined using the segmentation editor."

Distribution of Electric Field in Patients With Obsessive Compulsive Disorder Treated With Deep Brain Stimulation of the Bed Nucleus of Stria Terminalis

Publication: Acta Neurochir (Wien). 2022 Jan;164(1):193-202. PMID: 34652518 | PDF

Authors: Naesström M, Johansson J, Hariz M, Bodlund O, Wårdell K, Blomstedt P.

Institution: Division of Psychiatry, Department of Clinical Sciences, Umea University, Umea, Sweden

Abstract: Background: Deep brain stimulation (DBS) is being investigated as a treatment for therapy-refractory obsessive compulsive disorder (OCD). Many different brain targets are being trialled. Several of these targets such as the ventral striatum (including the nucleus accumbens (NAc)), the ventral capsule, the inferior thalamic peduncle, and the bed nucleus of stria terminalis (BNST)) belong to the same network, are anatomically very close to one another, or even overlap. Data is still missing on how various stimulation parameters in a given target will affect surrounding anatomical areas and impact the clinical outcome of DBS.

Methods: In a pilot study of eleven participants with DBS of the BNST, we investigate through patient-specific simulation of electric field, which anatomical areas are affected by the electric field, and if this can be related to the clinical results. Our study combined individual patient's stimulation parameters at 12- and 24-month follow-up with image data from the preoperative MRI and postoperative CT. These data were used to calculate the distribution of electric field and create individual anatomical models of the field of stimulation.

Results: The individual electric stimulation fields by stimulation in the BNST were similar at both the 12- and 24-month follow-up, involving mainly anterior limb of the internal capsule (ALIC), genu of the internal capsule (IC), BNST, fornix, anteromedial globus pallidus externa (GPe), and the anterior commissure. A statistical significant correlation (p < 0.05) between clinical effect measured by the Yale-Brown Obsessive Compulsive Scale and stimulation was found at the 12-month follow-up in the ventral ALIC and anteromedial GPe.

Conclusions: Many of the targets under investigation for OCD are in anatomical proximity. As seen in our study, off-target effects are overlapping. Therefore, DBS in the region of ALIC, NAc, and BNST may perhaps be considered to be stimulation of the same target.


"The results were visualized in 3D Slicer v.4.6.2"

Finite Element Analysis in Clinical Patients With Atherosclerosis

Publication: J Mech Behav Biomed Mater. 2022 Jan;125:104927. PMID: 34740008

Authors: Noble C, Carlson KD, Neumann E, Lewis B, Dragomir-Daescu D, Lerman A, Erdemir A, Young MD.

Institution: Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA.

Abstract: Endovascular plaque composition is strongly related to stent strut stress and is responsible for strut fatigue, stent failure, and possible in-stent restenosis. To evaluate the effect of plaque on artery wall resistance to expansion we performed in silico analysis of atherosclerotic vessels. We generated finite element models from in vivo intravascular ultrasound virtual histology images to determine local artery surface stiffness and determined which plaque structures have the greatest influence. We validated the predictive capacity of our modeling approach by testing an atherosclerotic peripheral artery ex vivo with pressure-inflation testing at physiological pressures ranging from 10 to 200 mmHg. For this purpose, the in silico deformation of the arterial wall was compared to that observed ex vivo. We found that calcification had a positive effect on surface stiffness with fibrous plaque and necrotic core having negative effects. Additionally, larger plaque structures demonstrated significantly higher average surface stiffness and calcification located nearer the lumen was also shown to increase surface stiffness. Therefore, more developed plaques will have greater resistance to expansion and higher stent strut stress, with calcification located near the lumen further increasing stress in localized areas. Thus, it may be expected that such plaque structures may increase the likelihood of localized stent strut fracture.


"Using the segment editor module in 3D Slicer, the high intensity pixels (representing primarily the artery wall) were segmented using the “threshold” effect."

Predictive Value of Thrombus Susceptibility for Cardioembolic Stroke by Quantitative Susceptibility Mapping

Publication: Quant Imaging Med Surg. 2022 Jan;12(1):550-7. PMID: 34993100 | PDF

Authors: Chen J, Zhang Z, Nie X, Xu Y, Liu C, Zhao X, Wang Y.

Institution: Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.

Abstract: Background: The hypointense blooming signal of thrombi on susceptibility-weighted imaging (SWI), known as the susceptibility vessel sign (SVS), is predictive of cardioembolic stroke. The SVS originates from the local magnetic susceptibility effect; thus, the susceptibility value of thrombi may provide useful information in discriminating stroke etiology. We aim to utilize quantitative susceptibility mapping (QSM) to assess thrombus's susceptibility value in acute ischemic stroke patients and explore the relationship of thrombus susceptibility with cardioembolic stroke.

Methods: From 2018 to 2020, 132 consecutive acute ischemic stroke patients with middle cerebral artery occlusion were recruited within 48 hours of onset. All patients underwent a three-dimensional multi-echo SWI scan using a 3 Tesla magnetic resonance imaging scanner. The SVS presence and the diameter of the SVS-related hypointense signal were assessed on SWI. QSM was applied to compute the susceptibility value of the thrombus. The receiver operating characteristic (ROC) methodology was used to define the optimal cutoff value of the susceptibility in QSM and the diameter on SWI for predicting cardioembolic stroke.

Results: The SVS was identified in 93 (70.5%) patients with symptomatic middle cerebral artery occlusion and was significantly associated with cardioembolism. The hyperintense signal on QSM in the corresponding middle cerebral artery occlusion was present in 116 (87.9%) patients. ROC analysis indicated that thrombus susceptibility had a greater area under the curve than that of the SVS diameter (0.88 vs. 0.70, P<0.001) and that the optimal cutoff value of thrombus susceptibility for cardioembolism was 0.35 ppm. Multivariate analysis demonstrated that thrombus susceptibility (≥0.35 ppm) was an independent predictor of cardioembolic stroke (odds ratio =20.75; 95% CI, 7.19-59.87; P<0.001), with sensitivity, specificity, a positive predictive value, and a negative predictive value of 85.2%, 80.8%, 75.4%, and 88.7%, respectively, while the SVS presence showed sensitivity, specificity, a positive predictive value, and a negative predictive value of 90.7%, 43.6%, 87.2%, and 52.7%, respectively.

Conclusions: Thrombus susceptibility provides superior diagnostic performance over the SVS for discriminating between cardioembolism and other stroke subtypes. Quantitative susceptibility measurements of thrombi may help predict cardioembolic stroke in patients with acute middle cerebral artery occlusion.


"The thrombus susceptibility value [in units of parts per million (ppm)] and thrombus volume of the ROIs were extracted using the 3D Slicer quantification module."

Knee Joint Unloading and Daily Physical Activity Associate With Cartilage T2 Relaxation Times 1 Month After ACL Injury

Publication: J Orthop Res. 2022 Jan;40(1):138-49. PMID: 33783030 | PDF

Authors: Wellsandt E, Kallman T, Golightly Y, Podsiadlo D, Dudley A, Vas S, Michaud K, Tao M, Sajja B, Manzer M.

Institution: Division of Physical Therapy Education, University of Nebraska Medical Center, Omaha, NE, USA.

Abstract: Osteoarthritis (OA) is prevalent after anterior cruciate ligament (ACL) injury, but mechanisms underlying its development are poorly understood. The purpose of this study was to determine if gait biomechanics and daily physical activity (PA) associate with cartilage T2 relaxation times, a marker of collagen organization and water content, 1 month after ACL injury. Twenty-seven participants (15-35 years old) without chondral lesions completed magnetic resonance imaging, three-dimensional gait analysis, and 1 week of PA accelerometry. Interlimb differences and ratios were calculated for gait biomechanics and T2 relaxation times, respectively. Multiple linear regression models adjusted for age, sex, and concomitant meniscus injury were used to determine the association between gait biomechanics and PA with T2 relaxation times, respectively. Altered knee adduction moment (KAM) impulse, less knee flexion excursion (kEXC) and higher daily step counts accounted for 35.8%-65.8% of T2 relaxation time variation in the weightbearing and posterior cartilage of the medial and lateral compartment (all p ≤ .011). KAM impulse was the strongest factor for T2 relaxation times in all models (all p ≤ .001). Lower KAM impulse associated with longer T2 relaxation times in the injured medial compartment (β = -.720 to -.901) and shorter T2 relaxation in the lateral compartment (β = .713 to .956). At 1 month after ACL injury, altered KAM impulse, less kEXC, and higher PA associated with longer T2 relaxation times, which may indicate poorer cartilage health. Statement of Clinical Significance: Gait biomechanics and daily PA are modifiable targets that may improve cartilage health acutely after ACL injury and slow progression to OA.

"Before uninjured segmentation, a manual and affine registration technique was used to register the injured reference images to the uninjured knee using 3D Slicer software."

Low-Dose Lung Radiation Therapy for COVID-19 Lung Disease: A Preclinical Efficacy Study in a Bleomycin Model of Pneumonitis

Publication: Int J Radiat Oncol Biol Phys. 2022 Jan 1;112(1):197-211. PMID: 34478832 | PDF

Authors: Jackson MR, Stevenson K, Chahal SK, Curley E, Finney GE, Gutierrez-Quintana R, Onwubiko E, Rupp A, Strathdee K, Williams K, MacLeod MKL, McSharry C, Chalmers AJ.

Institution: Institute of Cancer Sciences, University of Glasgow, UK.

Abstract: Purpose: Low-dose whole lung radiation therapy (LDLR) has been proposed as a treatment for patients with acute respiratory distress syndrome associated with SARS-CoV-2 infection, and clinical trials are underway. There is an urgent need for preclinical evidence to justify this approach and inform dose, scheduling, and mechanisms of action.

Methods and materials: Female C57BL/6 mice were treated with intranasal bleomycin sulfate (7.5 or 11.25 units/kg, day 0) and then exposed to whole lung radiation therapy (0.5, 1.0, or 1.5 Gy, or sham; day 3). Bodyweight was measured daily, and lung tissue was harvested for histology and flow cytometry on day 10. Computed tomography lung imaging was performed before radiation (day 3) and pre-endpoint (day 10).

Results: Bleomycin caused pneumonitis of variable severity, which correlated with weight loss. LDLR at 1.0 Gy was associated with a significant increase in the proportion of mice recovering to 98% of initial bodyweight, and a proportion of these mice exhibited less severe histopathologic lung changes. Mice experiencing moderate initial weight loss were more likely to respond to LDLR than those experiencing severe initial weight loss. In addition, LDLR (1.0 Gy) significantly reduced bleomycin-induced increases in interstitial macrophages, CD103+ dendritic cells (DCs), and neutrophil-DC hybrids. Overall, bleomycin-treated mice exhibited significantly higher percentages of non aerated lung in left than right lungs, and LDLR (1.0 Gy) limited further reductions in aerated lung volume in right but not left lungs. LDLR at 0.5 and 1.5 Gy did not improve bodyweight, flow cytometric, or radiologic readouts of bleomycin-induced pneumonitis.

Conclusions: Our data support the concept that LDLR can ameliorate acute inflammatory lung injury, identify 1.0 Gy as the most effective dose, and provide evidence that it is more effective in the context of moderate than severe pneumonitis. Mechanistically, LDLR at 1.0 Gy significantly suppressed bleomycin-induced accumulation of pulmonary interstitial macrophages, CD103+ DCs, and neutrophil-DC hybrids.

"Images were analyzed using the Lung CT analyzer module from the 3D Slicer software extension SlicerCIP."

Knee Cartilage T2 Relaxation Times 3 Months After ACL Reconstruction Are Associated With Knee Gait Variables Linked to Knee Osteoarthritis

Publication: J Orthop Res. 2022 Jan;40(1):252-9. PMID: 33783867

Authors: Williams JR, Neal K, Alfayyadh A, Lennon K, Capin JJ, Khandha A, Manal K, Potter HG, Snyder-Mackler L, Buchanan TS.

Institution: Department of Mechanical Engineering, University of Delaware, Newark, DE, USA.

Abstract: Osteoarthritis development after ACL reconstruction (ACLR) is not well understood. Investigators have examined associations between knee biomechanical alterations and quantitative MRI (qMRI) variables, reflective of cartilage health, 12-60 months following ACLR; however, none have done so early after surgery. As part of an exploratory study, 45 individuals (age, 23 ± 7 years) underwent motion analysis during walking and qMRI 3 months after ACLR. For each limb, peak knee adduction moment (pKAM) and peak knee flexion moment (pKFM) were determined using inverse dynamics and peak medial compartment force was calculated using a neuromusculoskeletal model. T2 relaxation times in the medial compartment and linear regressions were used to determine the associations between gait variables and deep and superficial cartilage T2 relaxation times in six regions. pKAM was positively associated with deep layer T2 relaxation times within the femoral central and posterior regions when examined in the involved limb and from an interlimb difference perspective (involved limb - uninvolved limb). After adjusting for age, the association between interlimb difference of pKAM and interlimb difference of deep layer T2 relaxation times in the tibial central region became significant (p = .043). Interlimb difference of pKFM was negatively associated with interlimb difference of deep layer T2 relaxation times within the femoral central and posterior regions. These associations suggest that degenerative pathways leading to osteoarthritis may be detectable as early as 3 months after reconstruction. Preventative therapeutic techniques may need to be employed early in the rehabilitation process to prevent cartilage degradation.

"All images were analyzed using the 3D Slicer software."

Prognostic Value of Tumor Measurement Parameters and SCC-Ag Changes in Patients With Locally-Advanced Cervical Cancer

Publication: Radiat Oncol. 2022 Jan 10;17(1):6. PMID: 35012582 | PDF

Authors: Chen W, Xiu S, Xie X, Guo H, Xu Y, Bai P, Xia X.

Institution: Department of Radiation Oncology, Fujian Medical University Cancer Hospital, Fujian Cancer Hospital, Fujian, China.

Abstract: Objective: To investigate the prognostic relevance of specific measurement parameters such as tumor diameter, tumor volume, tumor volume reduction rate (TVRR), and changes in the squamous cell carcinoma antigen (SCC-Ag) level in patients with locally-advanced cervical cancer (LACC) undergoing concurrent radiotherapy and chemotherapy.

Methods: This was a retrospective study of 203 patients with stage IIA-IVA cervical squamous cell carcinoma who were newly diagnosed at our hospital between January 2011 and March 2015. Clinical data and pre-and post-treatment imaging information were collected and each parameter was calculated using 3D Slicer software. The pre/post-treatment tumor diameter (TDpre/post), tumor volume (TVpre/post), SCC-Ag (SCCpre/post), and TVRR, SCC-Ag reduction rate (SCCRR) were analyzed and their prognostic relevance evaluated.

Results: The median follow-up was 69 months. The 5-year overall survival (OS) and disease progression-free survival (PFS) rates were 69.5% and 64.5%, respectively. On univariate analysis, TDpre/post, TVpre/post, TVRR, SCCpre/post and SCCRR showed significant association with OS and PFS (P < 0.05). On multivariate analysis, TDpre [Hazard ratio (HR) = 0.373, P = 0.028], TDpost (HR = 0.376, P = 0.003) and SCCpost (HR = 0.374, P = 0.001) were independent predictors of OS. TVRR (HR = 2.998, P < 0.001), SCCpre (HR = 0.563, P = 0.041), and SCCpost (HR = 0.253, P < 0.001) were independent predictors of PFS. Tumor measurement parameters showed a positive correlation with SCC-Ag (P < 0.05).

Conclusion: TDpre/post, TVpre/post, TVRR, SCCpre/post, and SCCRR were prognostic factors in LACC. TDpre/post and SCCpost showed the most significant prognostic value. TVRR and SCCpre/post were closely related to disease progression. Further studies should investigate the correlation between measurement parameters of tumor and SCC-Ag.

MRI Radiomic Features-Based Machine Learning Approach to Classify Ischemic Stroke Onset Time

Publication: J Neurol. 2022 Jan;269(1):350-60. PMID: 34218292

Authors: Zhang YQ, Liu AF, Man FY, Zhang YY, Li C, Liu YE, Zhou J, Zhang AP, Zhang YD, Lv J, Jiang WJ.

Institution: Department of Vascular Neurosurgery, New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Beijing, China.

Abstract: Purpose: We aimed to investigate the ability of MRI radiomics features-based machine learning (ML) models to classify the time since stroke onset (TSS), which could aid in stroke assessment and treatment options.

Methods: This study involved 84 patients with acute ischemic stroke due to anterior circulation artery occlusion (51 in the training cohort and 33 in the independent test cohort). Region of infarct segmentation was manually outlined by 3D Slicer software. Image processing including registration, normalization and radiomics features calculation were done in R (version 3.6.1). A total of 4312 radiomic features from each image sequence were captured and used in six ML models to estimate stroke onset time for binary classification (≤ 4.5 h). Receiver-operating characteristic curve (ROC) and other parameters were calculated to evaluate the performance of the models in both training and test cohorts.

Results: Twelve radiomics and six clinic features were selected to construct the ML models for TSS classification. The deep learning model-based DWI/ADC radiomic features performed the best for binary TSS classification in the independent test cohort, with an AUC of 0.754, accuracy of 0.788, sensitivity of 0.952, specificity of 0.500, positive predictive value of 0.769, and negative predictive value of 0.857, respectively. Furthermore, adding clinical information did not improve the performance of the DWI/ADC-based deep learning model. The TSS prediction models can be visited at: http://123.57.65.199:3838/deeptss/ .

Conclusions: A unique deep learning model based on DWI/ADC radiomic features was constructed for TSS classification, which could aid in decision making for thrombolysis in patients with unknown stroke onset.

Translation and Rotation Analysis Based on Stress MRI for the Diagnosis of Anterior Cruciate Ligament Tears

Publication: Quant Imaging Med Surg. 2022 Jan; 12(1): 257–68. PMID: 34993076 | PDF

Authors: Klon W, Domżalski M, Malinowski K,Sadlik B

Institution: St Luke’s Hospital, Bielsko-Biała, Poland.

Abstract: Due to the increasing need for a detailed biomechanical analysis of anterior cruciate ligament (ACL) lesions, the aim of the study was to develop a method of direct measurement of the three-dimensional tibial translation and rotation based on stress MRI.

Methods For the purpose of the study, thirty patients with acute ACL rupture and 17 healthy control subjects were selected. Based on clinical examination, they were qualified for MRI examination using the Arthroholder Device prototype to perform anterior tibial translation. Each examination was performed at 30° of knee flexion, initially without tibia translation and then using the force applied to the calf of 80 N. The femur and tibia were separately registered using rigid local SimpleITK landmark refinement; translation and rotation parameters were then calculated using the 3D transformation algorithms. The significance level was set at 0.05.

Results Initially, the device and method for obtaining the parameters of the 3D translation and rotation were validated. The pooled Standard Deviation for translation parameters was 0.81 mm and for rotation parameters 0.87°. Compared to the control group, statistically significant differences were found in parameters such as Anterior Shift [(median ± interquartile range) 3.89 mm ±6.55 vs. 0.90 mm ±2.78, P=0.002238] and External Rotation (−0.55° ±3.88 vs. −2.87° ±2.40, P=0.005074). Statistically significant correlations were observed in combined groups between Anterior Shift and parameters such as External Rotation (P=0.001611), PCL Tibial Attachment Point (pPCL) Anterior Shift (<0.000001), Rolimeter Measurement (P=0.000016), and Side-to-Side Difference (SSD) (P=0.000383). A significant statistical correlation was also observed between External Rotation and parameters such as Rolimeter (P=0.02261) and SSD (P=0.03458).

Conclusions The analysis of the anterior tibia translation using stress MRI and the proposed three-dimensional calculation method allows for a detailed analysis of the tibial translation and rotation parameters. The correlations showed the importance of external rotation during anterior tibial translation.

The Relationship of LDH and Hematological Parameters with Ischemic Volume and Prognosis in Cerebrovascular Disease

Publication: J Coll Physicians Surg Pak. 2022 Jan;32(1):42-5. PMID: 34983146

Authors: Alatlı T, Kocaoglu S, Akay E.

Institution: Department of Emergency, Faculty of Medicine, Balikesir University, Balikesir, Turkey.

Abstract: Objective: To determine whether lactate dehydrogenase (LDH), platelet-lymphocyte ratio (PLR), neutrophil-lymphocyte ratio (NLR), and lymphocyte-monocyte ratio (LMR) values can be used as a prediction for their relationship with stroke volume (SV) and for in-hospital mortality in stroke patients in Emergency Department (ED).

Study design: Analytical study.

Place and duration of study: Balikesir University, Turkey from 24/03/2021 to 30/06/2021.

Methodology: Patients aged 18 years or older, diagnosed with stroke in ED, were included in the study. Stroke volumes were calculated from diffusion-weighted images (DWi) with 3D Slicer software using image-based semi-automatic and manual segmentation methods.

Results: Of the 265 patients, 128 (48.3%) were males. SV was significantly higher in the non-survivor group than in the survivor group (p=0.007). NLR was significantly higher in the non-survivor group than in the survivor group (p=0.018).

Conclusion: The ratios of NLR and SV stand out as practical parameters for the estimation of mortality, prognosis, and management of patients diagnosed with acute stroke. Taking into account, these parameters in the diagnosis process and prognosis management in EDs will provide convenience.