Difference between revisions of "Main Page/SlicerCommunity/2021"

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'''Authors:''' Eördögh M, Baksa G, Grimm A, Bárány L, Petneházy Ö, Reisch R, Schroeder HWS, Briner HR, Hosemann W.
 
'''Authors:''' Eördögh M, Baksa G, Grimm A, Bárány L, Petneházy Ö, Reisch R, Schroeder HWS, Briner HR, Hosemann W.
  
'''Institution:''' Department of Neurosurgery, University Medicine Greifswald, Sauerbruchstraße, 17475, Greifswald, Germany.
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'''Institution:''' Department of Neurosurgery, University Medicine Greifswald, Sauerbruchstraße, Greifswald, Germany.
  
 
'''Abstract:''' The middle turbinate's basal lamella (3BL) is a variable landmark which needs to be understood in endoscopic transnasal skull base surgery. It comprises an anterior frontal and a posterior horizontal part and appears in its simplest depiction to be "L"-shaped, when viewed laterally. In this study we analyzed its 3D morphology and variations focusing on a precise and systematic description of the anatomy. CBCTs of 25 adults, 19 cadavers and 6 skulls (total: 100 sides) were investigated with the [http://www.slicer.org '''3D Slicer'''] software, creating 3D models of the 3BL. We introduced a novel geometrical classification of the 3BL's shape, based on segments. We analyzed their parameters and relationship to neighboring structures. When viewed laterally, there was no consistent "L"-shaped appearance of the 3BL, as it is frequently quoted. A classification of 9 segment types was used to describe the 3BL. The 3BLs had in average of 2.95 ± 0.70 segments (median: 3), the most frequent was the horizontal plate (23.05% of all segments), next a concave/convex plate (22.71%), then a sigma plate (22.37%). Further types were rare. We identified a horizontal plate in 68% of all lateral views whilst 32% of the 3BLs were vertical. A sigma-concave/convex-horizontal trisegmental 3BL was the most common phenotype (27%). Globally, the sigma-concave/convex pattern was present in 42%. The 3BL adhered the ethmoidal bulla in 87%. The segmenting method is eligible to describe the 3BL's sophisticated morphology.
 
'''Abstract:''' The middle turbinate's basal lamella (3BL) is a variable landmark which needs to be understood in endoscopic transnasal skull base surgery. It comprises an anterior frontal and a posterior horizontal part and appears in its simplest depiction to be "L"-shaped, when viewed laterally. In this study we analyzed its 3D morphology and variations focusing on a precise and systematic description of the anatomy. CBCTs of 25 adults, 19 cadavers and 6 skulls (total: 100 sides) were investigated with the [http://www.slicer.org '''3D Slicer'''] software, creating 3D models of the 3BL. We introduced a novel geometrical classification of the 3BL's shape, based on segments. We analyzed their parameters and relationship to neighboring structures. When viewed laterally, there was no consistent "L"-shaped appearance of the 3BL, as it is frequently quoted. A classification of 9 segment types was used to describe the 3BL. The 3BLs had in average of 2.95 ± 0.70 segments (median: 3), the most frequent was the horizontal plate (23.05% of all segments), next a concave/convex plate (22.71%), then a sigma plate (22.37%). Further types were rare. We identified a horizontal plate in 68% of all lateral views whilst 32% of the 3BLs were vertical. A sigma-concave/convex-horizontal trisegmental 3BL was the most common phenotype (27%). Globally, the sigma-concave/convex pattern was present in 42%. The 3BL adhered the ethmoidal bulla in 87%. The segmenting method is eligible to describe the 3BL's sophisticated morphology.
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Conclusions: By providing a method to analyze the morphology of the MC, we found that there is an asymmetry in the morphology of bilateral MC in the PTN and HC groups. It can be inferred that the flatness of the MC may be a cause of PTN.
 
Conclusions: By providing a method to analyze the morphology of the MC, we found that there is an asymmetry in the morphology of bilateral MC in the PTN and HC groups. It can be inferred that the flatness of the MC may be a cause of PTN.
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==An Unsupervised Learning Approach to Ultrasound Strain Elastography With Spatio-Temporal Consistency==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34298531 Phys Med Biol. 2021 Sep 3;66(17):175031. PMID: 34298531] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8417818/pdf/pmb_66_17_175031.pdf PDF]
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'''Authors:''' Delaunay R, Hu Y, Vercauteren T.
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'''Institution:''' Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, UK.
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'''Abstract:''' Quasi-static ultrasound elastography (USE) is an imaging modality that measures deformation (i.e. strain) of tissue in response to an applied mechanical force. In USE, the strain modulus is traditionally obtained by deriving the displacement field estimated between a pair of radio-frequency data. In this work we propose a recurrent network architecture with convolutional long-short-term memory decoder blocks to improve displacement estimation and spatio-temporal continuity between time series ultrasound frames. The network is trained in an unsupervised way, by optimising a similarity metric between the reference and compressed image. Our training loss is also composed of a regularisation term that preserves displacement continuity by directly optimising the strain smoothness, and a temporal continuity term that enforces consistency between successive strain predictions. In addition, we propose an open-accessin vivodatabase for quasi-static USE, which consists of radio-frequency data sequences captured on the arm of a human volunteer. Our results from numerical simulation andin vivodata suggest that our recurrent neural network can account for larger deformations, as compared with two other feed-forward neural networks. In all experiments, our recurrent network outperformed the state-of-the-art for both learning-based and optimisation-based methods, in terms of elastographic signal-to-noise ratio, strain consistency, and image similarity. Finally, our open-source code provides a [http://www.slicer.org '''3D Slicer'''] visualisation module that can be used to process ultrasound RF frames in real-time, at a rate of up to 20 frames per second, using a standard GPU.
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==A Mandible with the Temporomandibular Joint-A New FEM Model Dedicated to Strength and Fatigue Calculations of Bonding Elements Used in Fracture and Defect Surgery==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34501120 Materials (Basel). 2021 Sep 2;14(17):5031. PMID: 34501120] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8434464/pdf/materials-14-05031.pdf PDF]
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'''Authors:''' Mańkowski J, Piękoś J, Dominiak K, Klukowski P, Fotek M, Zawisza M, Żach P.
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'''Institution:''' Institute of Machine Design Fundamentals, Warsaw University of Technology, Warsaw, Poland.
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'''Abstract:''' The aim of the study was to develop a new FEM (finite element method) model of a mandible with the temporal joint, which can be used in the numerical verification of the work of bonding elements used in surgical operations of patients with mandibular fractures or defects. Most of such types of numerical models are dedicated to a specific case. The authors engaged themselves in building a model that can be relatively easily adapted to various types of tasks, allowing to assess stiffness, strength and durability of the bonded fragments, taking into account operational loads and fatigue limit that vary in time. The source of data constituting the basis for the construction of the model were DICOM (digital imaging and communications in medicine) files from medical imaging using computed tomography. On their basis, using the [http://www.slicer.org '''3D Slicer'''] program and algorithms based on the Hounsfield scale, a 3D model was created in the STL (standard triangle language) format. A CAD (computer-aided design) model was created using VRMesh and SolidWorks. An FEM model was built using HyperWorks and Abaqus/CAE. Abaqus solver was used for FEM analyses. A model meeting the adopted assumptions was built. The verification was conducted by analyzing the influence of the simplifications of the temporomandibular joint in the assessment of mandibular strain. The work of an undamaged mandible and the work of the bonded fracture of the mandible were simulated.
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==Mini Hyrax vs Hyrax Expanders in the Rapid Palatal Expansion in Adolescents With Posterior Crossbite: A Randomized Controlled Clinical Trial==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34467450 Prog Orthod. 2021 Sep 1;22(1):30. PMID: 34467450] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8408292/pdf/40510_2021_Article_365.pdf PDF]
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'''Authors:''' Silveira GS, Abreu LG, Palomo JM, da Matta Cid Pinto LS, de Sousa AA, Gribel BF, Oliveira DD.
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'''Institution:''' School of Dentistry, Pontifical Catholic University of Minas Gerais, Belo Horizonte, MG, Brazil.
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'''Abstract:''' Purpose: The aim of this study was to compare the dental effects, impact on quality of life, and pain perception of adolescents wearing Mini Hyrax and Hyrax expanders in rapid palatal expansion.
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Methods: Thirty-four adolescents aged 11 to 16 years, with maxillary transverse deficiency (unilateral or bilateral posterior crossbite), were randomly allocated into two groups, Mini Hyrax group and Hyrax group (1:1 ratio). Dental effects were evaluated by digitally superimposed pretreatment and postretention three-dimensional intraoral scans on the palatal rugaes using the software [http://www.slicer.org '''3D Slicer''']. Impact on quality of life was assessed with the OHIP-14 questionnaire applied in the pretreatment, posttreatment and postretention. Visual analog scale was applied 24, 48, and 72 h and 7 days after the first activation of the expander.
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Results: Thirty of the 34 adolescents recruited completed the study. There were no statistically significant differences in dentoalveolar effects between groups. OHIP-14 scores across time among Mini Hyrax wearers were similar to those of the Hyrax wearers. The inter-group comparisons showed no difference between groups with respect to the OHIP-14 scores in posttreatment and postretention (p > 0.05). There were no differences in pain perception between groups. Considering intra-group comparison, the reduction in pain perception among adolescents in the Mini Hyrax group was gradual. Among adolescents in the Hyrax group, a statistically significant reduction between 48 and 72 h was observed.
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Conclusion: There were no significant differences in dental effects, impact on quality of life and pain perception between adolescents wearing Mini Hyrax and Hyrax expanders in rapid palatal expansion.
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==A Novel Dynamic Electromagnetic Tracking Navigation System for Distal Locking of Intramedullary Nails==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34433127 Comput Methods Programs Biomed. 2021 Sep;209:106326. PMID: 34433127]
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'''Authors:''' Gao Y, Wang H, Tu P, Hu J, Wang Q, Chen X.
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'''Institution:''' School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China.
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'''Abstract:''' Background: The accurate distal locking of intramedullary (IM) nails is a clinical challenge for surgeons. Although many navigation systems have been developed, a real-time guide method with free radiation exposure, better user convenience, and high cost performance has not been proposed.
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Methods: This paper aims to develop an electromagnetic navigation system named TianXuan-MDTS that provides surgeons with a proven surgical solution. And the registration method with external landmarks for IM nails and calibration algorithm for guiders were proposed. A puncture experiment, model experiments measured by [http://www.slicer.org '''3D Slicer'''] and cadaver experiments (2 cadaveric leg specimens and 6 drilling operations) are conducted to evaluate its performance and stability.
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Results: The registration deviations (TRE) is 1.05± 0.13 mm. In the puncture experiment, a success rate of 96% can be achieved in 45.94 s. TianXuan-MDTS were evaluated on 3 tibia model. The results demonstrated that all 9 screw holes were successfully prepared at a rate of 100% in 91.67 s. And the entry point, end point, and angular deviations were 1.60±0.20 mm, 1.47±0.18 mm, and 3.10±0.84°, respectively. Postoperative fluoroscopy in cadaver experiments showed that all drills were in the distal locking holes, with a success rate of 100% and the average time 143.17± 18.27s.
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Conclusions: The experimental results indicate that our system with novel registration and calibration methods could serve as a feasible and promising tool to assist surgeons during distal locking.
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==TorchIO: A Python Library for Efficient Loading, Preprocessing, Augmentation and Patch-Based Sampling of Medical Images in Deep Learning==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34311413 Comput Methods Programs Biomed. 2021 Sep;208:106236. PMID: 34311413]
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'''Authors:''' Pérez-García F, Sparks R, Ourselin S.
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'''Institution:''' Department of Medical Physics and Biomedical Engineering, University College London, UK.
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'''Abstract:''' Background and objective: Processing of medical images such as MRI or CT presents different challenges compared to RGB images typically used in computer vision. These include a lack of labels for large datasets, high computational costs, and the need of metadata to describe the physical properties of voxels. Data augmentation is used to artificially increase the size of the training datasets. Training with image subvolumes or patches decreases the need for computational power. Spatial metadata needs to be carefully taken into account in order to ensure a correct alignment and orientation of volumes.
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Methods: We present TorchIO, an open-source Python library to enable efficient loading, preprocessing, augmentation and patch-based sampling of medical images for deep learning. TorchIO follows the style of PyTorch and integrates standard medical image processing libraries to efficiently process images during training of neural networks. TorchIO transforms can be easily composed, reproduced, traced and extended. Most transforms can be inverted, making the library suitable for test-time augmentation and estimation of aleatoric uncertainty in the context of segmentation. We provide multiple generic preprocessing and augmentation operations as well as simulation of MRI-specific artifacts.
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Results: Source code, comprehensive tutorials and extensive documentation for TorchIO can be found at http://torchio.rtfd.io/. The package can be installed from the Python Package Index (PyPI) running pip install torchio. It includes a command-line interface which allows users to apply transforms to image files without using Python. Additionally, we provide a graphical user interface within a TorchIO extension in [http://www.slicer.org '''3D Slicer'''] to visualize the effects of transforms.
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Conclusion: TorchIO was developed to help researchers standardize medical image processing pipelines and allow them to focus on the deep learning experiments. It encourages good open-science practices, as it supports experiment reproducibility and is version-controlled so that the software can be cited precisely. Due to its modularity, the library is compatible with other frameworks for deep learning with medical images.
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==Virtual Planning and CAD/CAM-Assisted Distraction for Maxillary Hypoplasia in Cleft Lip and Palate Patients: Accuracy Evaluation and Clinical Outcome==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33906808 J Craniomaxillofac Surg. 2021 Sep;49(9):799-808 PMID: 33906808]
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'''Authors:''' Gerbino G, Autorino U, Giaccone E, Novaresio A, Ramieri G.
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'''Institution:''' Division of Maxillofacial Surgery, Città della Salute e della Scienza Hospital, University of Torino, Italy.
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'''Abstract:''' The aim of this prospective study was to report the experience with a specific guided distraction protocol for the treatment of CLP patients with severe midface hypoplasia. From January 2016 to April 2019, six consecutive, non-growing, CLP patients with maxillary hypoplasia underwent a specific distraction protocol based on the use of VSP, CAD/CAM-generated surgical splints, cutting guides, prebent internal maxillary distractors, early removal of distractors, and acute callus manipulation and fixation. STL files for VSP, using multislice CT scans taken preoperatively (T0) and 3 months after distractor removal (T1) were superimposed using the free software [http://www.slicer.org '''3D Slicer'''] and Geomagic Wrap to evaluate the accuracy of maxillary repositioning and assess 3D bone changes. Clinical outcome was evaluated at the 1-year follow-up (T2). The patients and surgeon were satisfied with the occlusal and aesthetic outcomes. A maximum difference of 2 mm between the VSP and the actual surgical outcome was chosen as the success criterion for accuracy. The average linear difference for selected points was <2 mm in four patients and >2 mm in two patients. The average distance of the postoperative maxilla from the VSP model was 2.28 mm (median 1.85), while the average forward movement of the maxilla was 10.18 mm The protocol used is effective and accurate in the correction of severe maxillary hypoplasia in CLP patients. Early removal of the distractor and stabilization with plates reduces patient discomfort and does not jeopardize stability. This protocol should be reserved for complex cases due to the costs of the procedure, which are not negligible.
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==Novel 3D MRI Technique to Measure Perineal Membrane Structural Changes With Pregnancy and Childbirth: Technique Development and Measurement Feasibility==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33893825 Int Urogynecol J. 2021 Sep;32(9):2413-20. PMID: 33893825]
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'''Authors:''' Pipitone F, Swenson CW, DeLancey JOL, Chen L.
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'''Institution:''' Pelvic Floor Research Group, University of Michigan, Ann Arbor, MI, USA.
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'''Abstract:''' Introduction and hypothesis: We aimed to develop and validate a new MRI-based perineal membrane reconstruction and morphological measurement technique, and test its feasibility on nulliparous and parous women to determine the effects of pregnancy and childbirth on the perineal membrane.
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Methods: The perineal membrane was traced on high-resolution MRI using [http://www.slicer.org '''3D Slicer'''] and analyses performed using Rhinoceros 6.0 SR23®. Validation was done by comparing MRI-based perineal membrane reconstruction to dissection measurements in a cadaver. Feasibility of reconstruction was assessed in the following three groups: nulliparous (NP), primiparous women who underwent cesarean delivery (CD), and primiparous women with vaginal delivery (VD). The following parameters were measured: (1) swinging door angle, (2) bony and (3) soft tissue attachment lengths, (4) separation at perineal body level, (5) surface area, and (6) hiatal area. ANOVA and post-hoc comparisons were performed, and the effect sizes (d) were reported.
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Results: Model reconstruction was similar to cadaver dissection findings. Morphological measurements were feasible in all women (NP, n = 10; CS, n = 6; VD, n = 19). Swinging door angle was 13o greater in CD (p = 0.03; d = 1.15) and 16o greater in VD (p < 0.001; d = 1.41) compared to NP. VD showed 13% larger separation at the perineal body than NP (p = 0.097, d = 0.84) and 23% larger hiatal area than CD (p = 0.14, d = 0.94).
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Conclusion: This novel and anatomically validated MRI-based perineal membrane reconstruction technique is feasible. Preliminary findings show that pregnancy and childbirth both influence perineal membrane morphology with VD being associated with the largest swinging door angle and perineal body separation.
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==A Supplemental Technique for Preoperative Evaluation of Giant Intracranial Aneurysm==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33583010 J Neurol Surg A Cent Eur Neurosurg. 2021 Sep;82(5):424-9. PMID: 33583010]
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'''Authors:''' Wang HW, Wu C, Xue Z, Shu XJ, Sun ZH.
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'''Institution:''' Chinese PLA General Hospital, Neurosurgery, Beijing, China.
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'''Abstract:''' Background: Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in giant intracranial aneurysms (GIAs). In this study, we aimed to reconstruct the circulating and noncirculating parts of GIAs with the time-of-flight (TOF) and motion-sensitized driven-equilibrium (MSDE) sequences with [http://www.slicer.org '''3D Slicer'''] to reveal an integrated presentation of GIAs, compare its accuracy, and validate the usefulness for preoperative planning.
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Material and methods: Patients with GIAs who were treated with microsurgery in our department were included in this study. Both the TOF and MSDE sequence data for each patient were loaded into [http://www.slicer.org '''3D Slicer'''] for reconstruction and segmentation. The parameters measured by [http://www.slicer.org '''3D Slicer'''] were compared with those measured by DSA.
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Results: The mean diameter for all GIAs was 28.7 ± 1.5 mm (range, 25.9-31.9 mm). The mean diameter for all GIAs measured by DSA and [http://www.slicer.org '''3D Slicer'''] was 24.46 ± 5.25 and 28.66 ± 1.48 mm, respectively (t = 4.948, p < 0.01). When only the nonthrombotic GIAs were included, the mean diameter measured by DSA and [http://www.slicer.org '''3D Slicer'''] was 28.69 ± 2.03 and 28.97 ± 1.79 mm, respectively (t = 1.023, p = 0.323). The mean aneurysmal volume was 8,292.6 ± 1,175.1 mm3 and the mean thrombotic volume was 3,590.0 ± 1,003.7 mm3.
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Conclusion: The MSDE sequence brings diagnostic benefits as a comparison to other MRI sequences. Reconstruction of GIAs with [http://www.slicer.org '''3D Slicer'''] is a low-cost, dependable, and useful supplemental technique for surgical planning.
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==Maxillary Dentoskeletal Outcomes of the Expander With Differential Opening and the Fan-Type Expander: A Randomized Controlled Trial==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33580351 Clin Oral Investig. 2021 Sep;25(9):5247-56. PMID: 33580351] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8357852/pdf/nihms-1688380.pdf PDF]
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'''Authors:''' Massaro C, Garib D, Cevidanes L, Janson G, Yatabe M, Lauris JRP, Ruellas AC.
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'''Institution:''' Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil.
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'''Abstract:''' Objectives: The aim of this study was to compare the maxillary dentoskeletal outcomes of the expander with differential opening (EDO) and the fan-type expander (FE).
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Material and methods: Forty-eight patients with maxillary arch constriction in the mixed dentition were randomly allocated into EDO and FE groups. Cone-beam computed tomography scans were acquired before and after expansion. Linear and angular three-dimensional changes were assessed after cranial base superimposition using the ITK-SNAP and the [http://www.slicer.org '''3D Slicer'''] software. T or Mann-Whitney U tests were used for intergroup comparisons (P<0.05).
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Results: The EDO group comprised 24 patients treated with the EDO (13 female, 11 male; 7.6 years). The FE group comprised 24 patients treated with the FE (14 female, 10 male; 7.8 years). Skeletal lateral displacements were greater in the EDO group with greater expansion in the orbital, nasal cavity, zygomatic bone, and palate regions (mean intergroup differences of 0.4, 0.8, 0.9, and 1.1 mm, respectively). Intercanine expansion and canine buccal inclination were greater in the FE group, while intermolar distance changes and molar buccal inclination were greater in the EDO group. Similar changes were observed for vertical and anteroposterior displacements and palatal plane rotation.
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Conclusions: The EDO produced greater transverse skeletal expansion compared to the FE, with similar vertical and anteroposterior effects. Dental changes were greater in the molar region for patients treated with the EDO and in the canine region for patients treated with the FE.
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Clinical relevance: The EDO and the FE are capable of producing skeletal changes in the mixed dentition. The decision between both expanders will depend on the amount of expansion required in the molar region and in the nasomaxillary complex.
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==Utility of Machine Learning of Apparent Diffusion Coefficient (ADC) and T2-Weighted (T2W) Radiomic Features in PI-RADS Version 2.1 Category 3 Lesions to Predict Prostate Cancer Diagnosis==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34467426 Abdom Radiol (NY). 2021 Aug 31. PMID: 34467426]
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'''Authors:''' Lim CS, Abreu-Gomez J, Thornhill R, James N, Al Kindi A, Lim AS, Schieda N.
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'''Institution:''' Department of Medical Imaging, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.
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'''Abstract:''' Purpose: To evaluate if machine learning (ML) of radiomic features extracted from apparent diffusion coefficient (ADC) and T2-weighted (T2W) MRI can predict prostate cancer (PCa) diagnosis in Prostate Imaging-Reporting and Data System (PI-RADS) version 2.1 category 3 lesions.
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Methods: This multi-institutional review board-approved retrospective case-control study evaluated 158 men with 160 PI-RADS category 3 lesions (79 peripheral zone, 81 transition zone) diagnosed at 3-Tesla MRI with histopathology diagnosis by MRI-TRUS-guided targeted biopsy. A blinded radiologist confirmed PI-RADS v2.1 score and segmented lesions on axial T2W and ADC images using [http://www.slicer.org '''3D Slicer'''], extracting radiomic features with an open-source software (Pyradiomics). Diagnostic accuracy for (1) any PCa and (2) clinically significant (CS; International Society of Urogenital Pathology Grade Group ≥ 2) PCa was assessed using XGBoost with tenfold cross -validation.
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Results: From 160 PI-RADS 3 lesions, there were 50.0% (80/160) PCa, including 36.3% (29/80) CS-PCa (63.8% [51/80] ISUP 1, 23.8% [19/80] ISUP 2, 8.8% [7/80] ISUP 3, 3.8% [3/80] ISUP 4). The remaining 50.0% (80/160) lesions were benign. ML of all radiomic features from T2W and ADC achieved area under receiver operating characteristic curve (AUC) for diagnosis of (1) CS-PCa 0.547 (95% Confidence Intervals 0.510-0.584) for T2W and 0.684 (CI 0.652-0.715) for ADC and (2) any PCa 0.608 (CI 0.579-0.636) for T2W and 0.642 (CI 0.614-0.0.670) for ADC.
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Conclusion: Our results indicate ML of radiomic features extracted from T2W and ADC achieved at best moderate accuracy for determining which PI-RADS category 3 lesions represent PCa.
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==Optimized Fitting of a Midface Implant to Anchor a Magnetic Nasal Prosthesis Using 3D Printing==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34463790 HNO. 2021 Aug 31. PMID: 34463790]
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'''Authors:''' Wrobel C, Keppeler D, Meyer AC.
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'''Institution:''' Klinik für Hals-Nasen-Ohrenheilkunde, Universitätsmedizin Göttingen, Georg-August-Universität Göttingen, Göttingen, Deutschland.
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'''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.
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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, [http://www.slicer.org '''3D Slicer'''] allowed easy and fast reconstruction as well as adaptation for 3D printing using transparent plastic (MED610; stratasys Ltd., MN, USA).
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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.
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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.
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==Pars Triangularis Volume Asymmetry and Schneiderian First Rank Symptoms in Antipsychotic-naïve Schizophrenia==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34294619 Clin Psychopharmacol Neurosci. 2021 Aug 31;19(3):507-13. PMID: 34294619]| [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8316654/pdf/cpn-19-3-507.pdf PDF]
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'''Authors:''' Shivakumar V, Sreeraj VS, Kalmady SV, Gangadhar BN, Venkatasubramanian G.
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'''Institution:''' Department of Integrative Medicine, National Institute of Mental Health & NeuroSciences (NIMHANS), Bangalore, India.
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'''Abstract:''' Objective: Schizophrenia is a disorder of language and self, with first-rank symptoms (FRS) as one of the predominant features in a subset of patients. Abnormal language lateralization is hypothesized to underlie the neurobiology of FRS in schizophrenia. The role of Broca's area with its right-hemispheric counterpart, consisting of pars triangularis (PTr) and pars opercularis (POp) of the inferior frontal gyrus in FRS is undetermined. We compared the volumes and asymmetries of PTr & POp in anti-psychotic-naive schizophrenia patients with FRS (FRS[+]) with those without FRS (FRS[-]) and healthy-controls (HC) using three dimensional, interactive, semi-automated volumetric morphometry.
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Methods: Antipsychotic naïve FRS(+) (n = 27), FRS(-) (n = 24) and HC (n = 51) were carefully assessed with structured and semi-structured clinical tools. T1-weighted images were acquired in a 3T scanner. Volumes of regions of interest were measured independently for both sides using [http://www.slicer.org '''3D Slicer'''] software, and asymmetry indices were calculated.
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Results: FRS(+) but not FRS(-) had a significant volume deficit in right PTr after controlling for the potential confounding effects of age, sex, and intracranial volume (p = 0.029). There was a significant leftward asymmetry of PTr in patients with FRS (i.e., leftward asymmetry in patients) (p = 0.026). No significant volume/asymmetry abnormalities were observed in POp.
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Conclusion: Study findings suggest reduced right PTr volume with leftward asymmetry to be associated with FRS in schizophrenia. This is consistent with the loss of Yakovlevian torque in schizophrenia. Role of PTr in the neurobiology of schizophrenia as a disorder of self, speech, and social cognition needs further systematic evaluation in future research.
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==Stability and Reproducibility of Radiomic Features Based Various Segmentation Technique on MR Images of Hepatocellular Carcinoma (HCC)==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34573915 Diagnostics (Basel). 2021 Aug 30;11(9):1573. PMID: 34573915]| [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8468357/pdf/diagnostics-11-01573.pdf PDF]
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'''Authors:''' Haniff NSM, Abdul Karim MK, Osman NH, Saripan MI, Che Isa IN, Ibahim MJ.
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'''Institution:''' Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
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'''Abstract:''' Hepatocellular carcinoma (HCC) is considered as a complex liver disease and ranked as the eighth-highest mortality rate with a prevalence of 2.4% in Malaysia. Magnetic resonance imaging (MRI) has been acknowledged for its advantages, a gold technique for diagnosing HCC, and yet the false-negative diagnosis from the examinations is inevitable. In this study, 30 MR images from patients diagnosed with HCC is used to evaluate the robustness of semi-automatic segmentation using the flood fill algorithm for quantitative features extraction. The relevant features were extracted from the segmented MR images of HCC. Four types of features extraction were used for this study, which are tumour intensity, shape feature, textural feature and wavelet feature. A total of 662 radiomic features were extracted from manual and semi-automatic segmentation and compared using intra-class relation coefficient (ICC). Radiomic features extracted using semi-automatic segmentation utilized flood filling algorithm from [http://www.slicer.org '''3D Slicer'''] had significantly higher reproducibility (average ICC = 0.952 ± 0.009, p < 0.05) compared with features extracted from manual segmentation (average ICC = 0.897 ± 0.011, p > 0.05). Moreover, features extracted from semi-automatic segmentation were more robust compared to manual segmentation. This study shows that semi-automatic segmentation from 3D-Slicer is a better alternative to the manual segmentation, as they can produce more robust and reproducible radiomic features.
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==Postsurgical Stability of Temporomandibular Joint of Skeletal Class III Patients Treated with 2-Jaw Orthognathic Surgery via Computer-Aided Three-Dimensional Simulation and Navigation in Orthognathic Surgery (CASNOS)==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34409098 Biomed Res Int. 2021 Aug 6;2021:1563551. PMID: 34409098]| [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8367535/pdf/BMRI2021-1563551.pdf PDF]
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'''Authors:''' Wang LC, Lee YH, Tsai CY, Wu TJ, Teng YY, Lai JP, Lin SS, Chang YJ.
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'''Institution:''' Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
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'''Abstract:''' Objective: The aim of this study is to clarify the postsurgical stability of temporomandibular joints in skeletal class III patients treated with 2-jaw orthognathic surgery which was performed utilizing computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS) protocol.
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Materials and methods: 23 consecutive nongrowing skeletal class III patients with mandibular prognathism associated with maxillary retrognathism treated with 2-jaw orthognathic surgery between 2018 and 2019 were enrolled in this study. The surgery was planned according to the standardized protocol of CASNOS (computer-aided three-dimensional simulation and navigation in orthognathic surgery). Computed tomography (CT) scans were performed in all patients 3 weeks presurgically and 6 months postsurgically. ITKSNAP and [http://www.slicer.org '''3D Slicer'''] software were used to reconstruct three-dimensional facial skeletal images, to carry out image segmentation, and to superimpose and quantify the TMJ position changes before and after surgery. Amount of displacement of the most medial and lateral points of the condyles and the change of intercondylar angles were measured to evaluate the postsurgical stability of TMJ.
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Results: A total amount of 23 skeletal class III patients (female : male = 12 : 11) with age ranged from 20.3 to 33.5 years (mean: 24.39 ± 4.8 years old) underwent Le Fort I maxillary advancement and BSSO setback of the mandible. The surgical outcome revealed the satisfactory correction of their skeletal deformities. The mean displacement of the right most lateral condylar point (RL-RL') was 1.04 ± 0.42 mm and the mean displacement of the left most lateral condylar point (LL-LL') was 1.19 ± 0.41 mm. The mean displacement of the right most medial condylar point (RM-RM') was 1.03 ± 0.39 mm and the left most medial condylar point (LM-LM') was 0.96 ± 0.39 mm. The mean intercondylar angle was 161.61 ± 5.08° presurgically and 159.28 ± 4.92° postsurgically.
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Conclusion: The postsurgical position of TM joint condyles in our study only presented a mild change with all the landmark displacement within a range of 1.2 mm. This indicates the bimaxillary orthognathic surgery via 3D CASNOS protocol can achieve a desired and stable result of TMJ position in treating skeletal class III adult patients with retrognathic maxilla and prognathic mandible.
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|}
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==Performances of Whole Tumor Texture Analysis Based on MRI: Predicting Preoperative T Stage of Rectal Carcinomas==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34414105 Front Oncol. 2021 Aug 3;11:678441. PMID: 34414105]| [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8369414/pdf/fonc-11-678441.pdf PDF]
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'''Authors:''' You J, Yin J.
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'''Institution:''' Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China.
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'''Abstract:''' Objective: To determine whether there is a correlation between texture features extracted from high-resolution T2-weighted imaging (HR-T2WI) or apparent diffusion coefficient (ADC) maps and the preoperative T stage (stages T1-2 versus T3-4) in rectal carcinomas.
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Materials and methods: One hundred and fifty four patients with rectal carcinomas who underwent preoperative HR-T2WI and diffusion-weighted imaging were enrolled. Patients were divided into training (n = 89) and validation (n = 65) cohorts. [http://www.slicer.org '''3D Slicer'''] was used to segment the entire volume of interest for whole tumors based on HR-T2WI and ADC maps. The least absolute shrinkage and selection operator (LASSO) was performed to select feature. The significantly difference was tested by the independent sample t-test and Mann-Whitney U test. The support vector machine (SVM) model was used to develop classification models. The correlation between features and T stage was assessed by Spearman's correlation analysis. Multivariate logistic regression analysis was performed to identify independent predictors of tumor invasion. The performance of classifiers was evaluated by the receiver operating characteristic (ROC) curves.
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Results: The wavelet HHH NGTDM strength (RS = -0.364, P < 0.001) from HR-T2WI was an independent predictor of stage T3-4 tumors. The shape maximum 2D diameter column (RS = 0.431, P < 0.001), log σ = 5.0 mm 3D first-order maximum (RS = 0.276, P = 0.009), and log σ = 5.0 mm 3D first-order interquartile range (RS = -0.229, P = 0.032) from ADC maps were independent predictors. In training cohorts, the classification models from HR-T2WI, ADC maps and the combination of two achieved the area under the ROC curves (AUCs) of 0.877, 0.902 and 0.941, with the accuracy of 79.78%, 89.86% and 89.89%, respectively. In validation cohorts, the three models achieved AUCs of 0.845, 0.881 and 0.910, with the accuracy of 78.46%, 83.08% and 87.69%, respectively.
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Conclusions: Texture analysis based on ADC maps shows more potential than HR-T2WI in identifying preoperative T stage in rectal carcinomas. The combined application of HR-T2WI and ADC maps may help to improve the accuracy of preoperative diagnosis of rectal cancer invasion.
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|}
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==Patient-Specific Coronary Artery Bypass Graft 3D Printing: Implications for Procedural Planning in Complex Percutaneous Coronary Interventions==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34338650 J Invasive Cardiol. 2021 Aug;33(8):E592-E603. PMID: 34338650]| [https://www.hmpgloballearningnetwork.com/site/jic/original-contribution/patient-specific-coronary-artery-bypass-graft-3d-printing PDF]
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'''Authors:''' Memon S, Friend E, Samuel SP, Goykhman I, Janzer S, Kalra S, George JC.
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'''Institution:''' Cardiac Catheterization Laboratory, Einstein Medical Center, 5501 Old York Road, Philadelphia, PA, USA.
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'''Abstract:''' Background: Three-dimensional (3D) printing technology has seen tremendous growth in augmenting didactics, research, and preprocedural planning with structural heart procedures. Limited investigative efforts have been made in other areas of the cardiovascular spectrum. 3D-printed models (PMs) of anatomically complex coronary artery bypass graft (CABG) patients from coronary computed tomography angiography (CCTA) have implications for adaptive learning and preprocedural planning.
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Methods: Five patients with CCTA who underwent subsequent coronary angiography were 3D printed for retrospective comparisons. Standard [http://www.slicer.org '''3D Slicer'''] software was used to create a computer-aided image of the ascending aorta, native coronary arteries, bypass grafts, aortic arch, and great vessels and 3D printed using polylactic acid filament. The models were painted with acrylic paint to highlight anatomical features and comparison was made with coronary angiography and 3D-CTA images.
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Results: All occluded vein grafts, left and right internal mammary artery (IMA) grafts, patent saphenous vein grafts, along with distal graft anastomotic sites, were accurately 3D printed. In cases with chronic total occlusions (CTOs), ambiguous ostial caps, mid or distal vessel chronic occlusions, and occlusions seen as CTOs on coronary angiography were 3D printed showing either distal vessel reconstitution via collaterals or complete arterial filling seen in a setting of calcification, microchannels, and collateral flow. Lastly, 3D printing of the aortic root and great vessels allowed for better appreciation of vessel tortuosity to aid in the cannulation of IMA grafts and optimizing engagement with diagnostic and guiding catheters.
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Conclusions: 3D printing of anatomically complex CABG patients has the potential to assist with preprocedural planning and operator understanding of complex coronary anatomy.
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|}
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==Efficacy of Invisalign Attachments: A Retrospective Study==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34217574 Am J Orthod Dentofacial Orthop. 2021 Aug;160(2):250-258. PMID: 34217574]
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'''Authors:''' Karras T, Singh M, Karkazis E, Liu D, Nimeri G, Ahuja B.
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'''Institution:''' Department of Orthodontics, Marquette University School of Dentistry, Milwaukee, WI, USA.
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'''Abstract:''' Introduction: The purpose of this study was to compare the efficacy of Invisalign's (Align Technology, Santa Clara, Calif) optimized and conventional attachments on rotational and extrusive tooth movements.
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Methods: Initial, predicted, and achieved digital dental models from 100 orthodontic patients were exported from Invisalign's ClinCheck software as stereolithography files and subsequently imported into the [http://www.slicer.org '''3D Slicer'''] CMF program v.4.7.0  for superimpositions on posterior teeth with no planned movement. Rotational and extrusive measurements for both optimized and conventional attachments were made on 382 teeth from the superimposition of the initial and predicted models (predicted movement) and from the superimposed initial and achieved models (achieved movement). Predicted and achieved movements were compared along with movements of teeth with optimized and conventional attachments.
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Results: Differences between accuracies of tooth movements using optimized vs conventional attachments for both rotation and extrusion were neither statistically nor clinically significant. Mean predicted values were larger than mean achieved values for all attachment types and movements (P < 0.0001). For extrusion, the mean difference between predicted and achieved movements was clinically significant (0.40 mm and 0.62 mm for optimized and conventional attachments, respectively). Overall, the mean accuracy was 57.2%. Mean accuracy was 63.2% for rotation and 47.6% for extrusion. Interproximal reduction or spacing did not significantly affect accuracy.
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Conclusions: Conventional attachment types may be just as effective as Invisalign's proprietary optimized attachments for rotations of canines and premolars and extrusion of incisors and canines. Clinicians should consider overcorrecting tooth movements, especially anterior tooth extrusion.
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==Association of Regional White Matter Hyperintensity Volumes With Cognitive Dysfunction and Vascular Risk Factors in Patients With Amnestic Mild Cognitive Impairment==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34105230 Geriatr Gerontol Int. 2021 Aug;21(8):644-50. PMID: 34105230]| [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8453570/pdf/GGI-21-644.pdf PDF]
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'''Authors:''' Hirao K, Yamashita F, Sakurai S, Tsugawa A, Haime R, Fukasawa R, Sato T, Kanetaka H, Umahara T, Sakurai H, Hanyu H, Shimizu S.
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'''Institution:''' Department of Geriatric Medicine, Tokyo Medical University, Tokyo, Japan.
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'''Abstract:''' Aim: White matter hyperintensities (WMH) obtained by magnetic resonance imaging (MRI) have been reported to promote neurodegeneration and cognitive decline in patients with mild cognitive impairment (MCI). However, little is known about the association between regional WMH (rWMH) and cognitive dysfunction in MCI. We hence investigated the associations between rWMH volumes and cognitive dysfunction in MCI.
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Methods: Thirty-eight subjects with amnestic MCI were analysed. The volumes of periventricular hyperintensities (PVH) and deep WMH (DWMH) were measured on a T2-FLAIR MRI using [http://www.slicer.org '''3D Slicer'''], and regional PVH and DWMH (rPVH and rDWMH) volumes were calculated. The associations of rPVH and rDWMH volumes with cognition and blood levels of various molecules were investigated. Furthermore, rPVH and rDWMH volumes were compared between MCI with vascular risk factors, such as hypertension, diabetes mellitus (DM), and dyslipidemia, and those without these risk factors.
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Results: rPVH volume (bilateral cornu frontale, pars parietalis, and cornu occipitale) positively correlated with Trail Making Test-A/B scores and CysC level, whereas rDWMH volume did not correlate with any of the items. rPVH volumes (right cornu frontale, bilateral pars parietalis and cornu occipitale, and right pars temporalis) and rDWMH volumes (left frontal and parietal lobes) were significantly larger in MCI patients with DM than in those without.
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Conclusions: PVH volumes (bilateral areas of cornu frontale, pars parietalis, and cornu occipitale) were closely associated with attention and executive dysfunction. Serum CysC level and DM were associated with WMH volume, suggesting that CysC level and DM might be important markers for determining treatment strategies for white matter abnormalities in MCI.
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==Development and Validation of a CT-Based Nomogram for Preoperative Prediction of Clear Cell Renal Cell Carcinoma Grades==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33515086 Eur Radiol. 2021 Aug;31(8):6078-6086. PMID: 33515086]
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'''Authors:''' Zheng Z, Chen Z, Xie Y, Zhong Q, Xie W.
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'''Institution:''' Department of Urology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
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'''Abstract:''' Objectives: Nuclear grades are proved to be one of the most significant prognostic factors for clear cell renal cell carcinoma (ccRCC). Radiomics nomogram is a widely used noninvasive tool that could predict tumor phenotypes. In this study, we performed radiomics analysis to develop and validate a CT-based nomogram for the preoperative prediction of nuclear grades in ccRCC.
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Method: CT images and clinical data of 258 ccRCC patients were retrieved from the Cancer Imaging Archive (TCIA). Radiomics features were extracted from arterial-phase CT images using [http://www.slicer.org '''3D Slicer'''] software. LASSO regression model was performed to develop a radiomics signature in the training set (n = 143). A radiomics nomogram was constructed combining radiomics signature and selected clinical predictors. Receiver operating characteristic (ROC) curve and calibration curve were used to determine the performance of the radiomics nomogram in the training and validation set (n = 115). Decision curve analysis was used to assess the clinical usefulness of the CT-based nomogram.
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Results: One thousand three hundred sixteen radiomics features were extracted from arterial-phase CT images. A radiomics signature, consisting of 20 features, was developed and showed a favorable performance in discriminating nuclear grades with an area under the curve (AUC) of 0.914 and 0.846 in the training and validation set, respectively. The CT-based nomogram, including the radiomics signature and the CT-determined T stage, achieved good calibration and discrimination in the training set (AUC, 0.929; 95% CI, 0.886-0.972) and validation set (AUC, 0.876; 95% CI, 0.812-0.939). Decision curve analysis demonstrated the clinical usefulness of the CT-based nomogram.
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Conclusion: The noninvasive CT-based nomogram, including radiomics signature and CT-determined T stage, could improve the accuracy of preoperative grading of ccRCC and provide individualized treatment for ccRCC patients.
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==Choroidal Macrovessel: Systematic Review and Analysis of Anatomic Origin==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34332961 Surv Ophthalmol. 2021 Jul 29:S0039-6257(21)00166-1. PMID: 34332961]
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'''Authors:''' Bowen RC, Raval V, Soto H, Singh AD.
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'''Institution:''' Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA.
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'''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 [http://www.slicer.org '''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.
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==Volumetric Accuracy Analysis of Virtual Safety Barriers for Cooperative-Control Robotic Mastoidectomy==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34325455 Otol Neurotol. 2021 Jul 28. PMID: 34325455]
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'''Authors:''' Ding AS, Capostagno S, Razavi CR, Li Z, Taylor RH, Carey JP, Creighton FX.
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'''Institution:''' Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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'''Abstract:''' Hypothesis: Virtual fixtures can be enforced in cooperative-control robotic mastoidectomies with submillimeter accuracy.
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Background: Otologic procedures are well-suited for robotic assistance due to consistent osseous landmarks. We have previously demonstrated the feasibility of cooperative-control robots (CCRs) for mastoidectomy. CCRs manipulate instruments simultaneously with the surgeon, allowing the surgeon to control instruments with robotic augmentation of motion. CCRs can also enforce virtual fixtures, which are safety barriers that prevent motion into undesired locations. Previous studies have validated the ability of CCRs to allow a novice surgeon to safely complete a cortical mastoidectomy. This study provides objective accuracy data for CCR-imposed safety barriers in cortical mastoidectomies.
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Methods: Temporal bone phantoms were registered to a CCR using preoperative computed tomography (CT) imaging. Virtual fixtures were created using [http://www.slicer.org '''3D Slicer'''], with 2D planes placed along the external auditory canal, tegmen, and sigmoid, converging on the antrum. Five mastoidectomies were performed by a novice surgeon, moving the drill to the limit of the barriers. Postoperative CT scans were obtained, and Dice coefficients and Hausdorff distances were calculated.
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Results: The average modified Hausdorff distance between drilled bone and the preplanned volume was 0.351 ± 0.093 mm. Compared with the preplanned volume of 0.947 cm3, the mean volume of bone removed was 1.045 cm3 (difference of 0.0982 cm3 or 10.36%), with an average Dice coefficient of 0.741 (range, 0.665-0.802).
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Conclusions: CCR virtual fixtures can be enforced with a high degree of accuracy. Future studies will focus on improving accuracy and developing 3D fixtures around relevant surgical anatomy.
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==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==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34245016 J Periodontol. 2021 Jul 9. PMID: 34245016]
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'''Authors:''' Dowlatshahi S, Chen CY, Zigdon-Giladi H, Horwitz J, Ahn C, Kim DM, Machtei EE.
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'''Institution:''' Division of Periodontology, Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA.
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'''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).
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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 [http://www.slicer.org '''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.
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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).
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Conclusion: FDBA/CM yielded better albeit moderate increase in the volume of the edentulous ridge, while OV scaffolds failed to produce similar results.
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==Radiomics AI Prediction for Head and Neck Squamous Cell Carcinoma (HNSCC) Prognosis and Recurrence With Target Volume Approach==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34381946 BJR Open. 2021 Jul 5;3(1):20200073. PMID: 34381946] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8320130/pdf/bjro.20200073.pdf PDF]
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'''Authors:''' Fh T, Cyw C, Eyw C.
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'''Institution:''' School of Medical and Health Sciences, Tung Wah College, Hong Kong, Hong Kong.
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'''Abstract:''' Objectives: To evaluate the performance of radiomics features extracted from planning target volume (PTV) and gross tumor volume (GTV) in the prediction of the death prognosis and cancer recurrence rate for head and neck squamous cell carcinoma (HNSCC).
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Methods: 188 HNSCC patients' planning CT images with radiotherapy structures sets were acquired from Cancer Imaging Archive (TCIA). The [http://www.slicer.org '''3D Slicer'''] v.4.10.2 with the PyRadiomics extension (Computational Imaging and Bioinformatics Lab, Harvard medical School) was used to extract radiomics features from the radiotherapy planning images. An in-house developed deep learning artificial neural networks (DL-ANN) model was used to predict death prognosis and cancer recurrence rate based on the features extracted from GTV and PTV of the CT images.
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Results: The PTV radiomics features with DL-ANN model could achieve 77.7% accuracy with overall AUC equal to 0.934 and 0.932 when predicting HNSCC-related death prognosis and cancer recurrence respectively. Furthermore, the DL-ANN model can achieve an accuracy of 74.3% with AUC equal to 0.947 and 0.956 for the HNSCC-related death prognosis and cancer recurrence respectively using GTV features.
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Conclusion: Using both GTV and PTV radiomics features in the DL-ANN model, can aid in predicting HNSCC-related death prognosis and cancer recurrence. Clinicians may find it helpful in formulating different treatment regimens and facilitate personized medicine based on the predicted outcome when performing GTV and PTV delineation.
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Advances in knowledge: Radiomics features of GTV and PTV are reliable prognosis and recurrence predicting tools, which may help clinicians in GTV and PTV delineation to facilitate delivery of personalized treatment.
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==MRI Radiomic Features-Based Machine Learning Approach to Classify Ischemic Stroke Onset Time==
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34218292 J Neurol. 2021 Jul 4. PMID: 34218292]
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'''Authors:''' Zhang YQ, Liu AF, Man FY, Zhang YY, Li C, Liu YE, Zhou J, Zhang AP, Zhang YD, Lv J, Jiang WJ.
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'''Institution:''' Department of Vascular Neurosurgery, New Era Stroke Care and Research Institute, The PLA Rocket Force Characteristic Medical Center, Beijing, China.
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'''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.
 +
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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 [http://www.slicer.org '''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/ .
 +
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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.
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|}
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==Preliminary Computed Tomography Radiomics Model for Predicting Pretreatment CD8+ T-Cell Infiltration Status for Primary Head and Neck Squamous Cell Carcinoma==
 +
 +
{| width="100%"
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34519454 J Comput Assist Tomogr. 2021 Jul-Aug 01;45(4):629-36. PMID: 34519454]
 +
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'''Authors:''' Wang CY, Ginat DT.
 +
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'''Institution:''' Department of Radiology, The University of Chicago, Chicago, IL, USA.
 +
 +
'''Abstract:''' Purpose: Immunotherapy has emerged as a treatment option for head and neck squamous cell carcinoma (HNSCC), with tumor response being linked to the CD8+ T-cell inflammation. The purpose of this study is to assess whether computed tomography (CT) radiomic analysis can predict CD8+ T-cell enrichment in HNSCC primary tumors.
 +
 +
Methods: This retrospective study included 71 patients from a head and neck cancer genomics cohort with CD8+ T-cell enrichment status. Pretreatment contrast-enhanced neck CT scans were retrospectively reviewed using [http://www.slicer.org '''3D Slicer'''] for primary lesion segmentation.The SlicerRadiomics extension was used to extract 107 radiomic features. Ridge regression and lasso regression were applied for feature selection and model construction.
 +
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Results: Lasso regression defined Coarseness as the most important variable, followed by SmallDependenceEmphasis, SmallAreaLowGrayLevelEmphasis, Contrast.1, and Correlation.Ridge regression defined Coarseness as the most important variable, followed by SmallDependenceLowGrayLevelEmphasis, Contrast.1, DependenceNonUniformityNormalized, and Idmn. These variables identified by lasso and ridge regressions were used to create a combined logistic regression model. The area under the curve (AUC) for the lasso-generated model was 0.786 (95% confidence interval [CI], 0.532-1.000), and the AUC for the ridge-generated model was 0.786 (95% CI, 0.544-1.000). Combining the radiomic variables identified by lasso and ridge regressions with clinical characteristics including alcohol use, tobacco use, anatomic site, and initial T stage produced a model with an AUC of 0.898 (95% CI, 0.731-1.000).
 +
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Conclusions: T-cell inflammation status of HNSCC primary tumors can be predicted using radiomic analysis of CT imaging and thereby help identify patients who would respond well to immunotherapy.
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|}
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==3D-Printed, Patient-Specific DIEP Flap Templates for Preoperative Planning in Breast Reconstruction: A Prospective Case Series==
 +
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{| width="100%"
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34422590 Gland Surg. 2021 Jul;10(7):2192-2199. PMID: 34422590] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8340344/pdf/gs-10-07-2192.pdf PDF]
 +
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'''Authors:''' Chae MP, Hunter-Smith DJ, Chung RD, Smith JA, Rozen WM.
 +
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'''Institution:''' Department of Surgery, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.
 +
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'''Abstract:''' Background: Modern imaging technologies, such as computed tomographic angiography (CTA), can be useful for preoperative assessment in deep inferior epigastric artery perforator (DIEP) flap surgery. Planning perforator flap design can lead to improved surgical efficiency. However, current imaging modalities are limited by being displayed on a two-dimensional (2D) surface. In contrast, a 3D-printed model provides tactile feedback that facilitates superior understanding. Hence, we have 3D-printed patient-specific deep inferior epigastric artery perforator (DIEP) templates, in an affordable and convenient manner, for preoperative planning.
 +
 +
Methods: Twenty consecutive patients undergoing 25 immediate or delayed post-mastectomy autologous breast reconstruction with DIEP or muscle-sparing transverse rectus abdominis (MS-TRAM) flaps are recruited prospectively. Using free, open-source softwares ([http://www.slicer.org '''3D Slicer'''], Autodesk MeshMixer, and Cura) and desktop 3D printers (Ultimaker 3E and Moment), we created a template based on a patient's abdominal wall anatomy from CTA, with holes and lines indicating the position of perforators, their intramuscular course and the DIEA pedicle.
 +
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Results: The mean age of patients was 52 [38-67]. There were 15 immediate and 10 delayed reconstructions. 3D printing time took mean 18 hours and 123.7 g of plastic filament, which calculates to a mean material cost of AUD 8.25. DIEP templates accurately identified the perforators and reduced intraoperative perforator identification by 7.29 minutes (P=0.02). However, the intramuscular dissection time was not affected (P=0.34). Surgeons found the template useful for preoperative marking (8.6/10) and planning (7.9/10), but not for intramuscular dissection (5.9/10). There were no immediate flap-related complications.
 +
 +
Conclusions: Our 3D-printed, patient-specific DIEP template is accurate, significantly reduces intraoperative perforator identification time and, hence, may be a useful tool for preoperative planning in autologous breast reconstruction.
 +
|}
 +
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==An Efficient Method for Aneurysm Volume Quantification Applicable in Any Shape and Modalities==
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{| width="100%"
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34185985 J Korean Neurosurg Soc. 2021 Jul;64(4):514-23. PMID: 34185985] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8273770/pdf/jkns-2020-0255.pdf PDF]
 +
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'''Authors:''' Chung J, Ko JH.
 +
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'''Institution:''' Department of Neurosurgery, Dankook University College of Medicine, Cheonan, Korea.
 +
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'''Abstract:''' Objective: Aneurysm volume quantification (AVQ) using the equation of ellipsoid volume is widely used although it is inaccurate. Furthermore, AVQ with 3-dimensional (3D) rendered data has limitations in general use. A novel universal method for AVQ is introduced for any diagnostic modality and application to any shape of aneurysms.
 +
 +
Methods: Relevant AVQ studies published from January 1997 to June 2019 were identified to determine common methods of AVQ. The basic idea is to eliminate the normal artery volume from 3D model with the aneurysm. After Digital Imaging and Communications in Medicine (DICOM) data is converted and exported to stereolithography (STL) file format, the 3D STL model is modified to remove the aneurysm and the volume difference between the 3D model with/without the aneurysm is defined as the aneurysm volume. Fifty randomly selected aneurysms from DICOM database were used to validate the different AVQ methods.
 +
 +
Results: We reviewed and categorized AVQ methods in 121 studies. Approximately 60% used the ellipsoid method, while 24% used the 3D model. For 50 randomly selected aneurysms, volumes were measured using [http://www.slicer.org '''3D Slicer'''], RadiAnt, and ellipsoid method. Using [http://www.slicer.org '''3D Slicer'''] as the reference, the ratios of mean difference to mean volume obtained by RadiAnt and ellipsoid method were -1.21±7.46% and 4.04±30.54%, respectively. The deviations between RadiAnt and [http://www.slicer.org '''3D Slicer'''] were small despite of aneurysm shapes, but those of ellipsoid method and [http://www.slicer.org '''3D Slicer'''] were large.
 +
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Conclusion: In spite of inaccuracy, ellipsoid method is still mostly used. We propose a novel universal method for AVQ that is valid, low cost, and easy to use.
 +
|}
 +
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==Real-Time Tool Detection for Workflow Identification in Open Cranial Vault Remodeling==
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{| width="100%"
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34206962 Entropy (Basel). 2021 Jun 26;23(7):817. PMID: 34206962] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8303376/pdf/entropy-23-00817.pdf PDF]
 +
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'''Authors:''' Pose Díez de la Lastra A, García-Duarte Sáenz L, García-Mato D, Hernández-Álvarez L, Ochandiano S, Pascau J.
 +
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'''Institution:''' Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Leganés, Spain.
 +
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'''Abstract:''' Deep learning is a recent technology that has shown excellent capabilities for recognition and identification tasks. This study applies these techniques in open cranial vault remodeling surgeries performed to correct craniosynostosis. The objective was to automatically recognize surgical tools in real-time and estimate the surgical phase based on those predictions. For this purpose, we implemented, trained, and tested three algorithms based on previously proposed Convolutional Neural Network architectures (VGG16, MobileNetV2, and InceptionV3) and one new architecture with fewer parameters (CranioNet). A novel [http://www.slicer.org '''3D Slicer'''] module was specifically developed to implement these networks and recognize surgical tools in real time via video streaming. The training and test data were acquired during a surgical simulation using a 3D printed patient-based realistic phantom of an infant's head. The results showed that CranioNet presents the lowest accuracy for tool recognition (93.4%), while the highest accuracy is achieved by the MobileNetV2 model (99.6%), followed by VGG16 and InceptionV3 (98.8% and 97.2%, respectively). Regarding phase detection, InceptionV3 and VGG16 obtained the best results (94.5% and 94.4%), whereas MobileNetV2 and CranioNet presented worse values (91.1% and 89.8%). Our results prove the feasibility of applying deep learning architectures for real-time tool detection and phase estimation in craniosynostosis surgeries.
 +
|}
 +
 +
==Association Between Tumor Size and Peritumoral Brain Edema in Patients With Convexity and Parasagittal Meningiomas==
 +
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{| width="100%"
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 +
'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34111188 PLoS One. 2021 Jun 10;16(6):e0252945. PMID: 34111188] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8191970/pdf/pone.0252945.pdf PDF]
 +
 +
'''Authors:''' Shin C, Kim JM, Cheong JH, Ryu JI, Won YD, Ko Y, Han MH.
 +
 +
'''Institution:''' Department of Neurosurgery, Hanyang University Guri Hospital, Guri, Gyonggi-do, Korea.
 +
 +
'''Abstract:''' Background and purpose: Peritumoral brain edema (PTBE) is a common complication in meningioma and disruption of the tumor-brain barrier in meningioma is crucial for PTBE formation. To evaluate the association between meningioma size and PTBE, we measured meningioma volumes using the [http://www.slicer.org '''3D Slicer'''] in patients with convexity and parasagittal meningiomas.
 +
 +
Methods: Receiver operating characteristic curve analysis was used to determine the optimal cut-off meningioma volume values for predicting PTBE occurrence. Logistic regressions were used to estimate the odds ratios for PTBE occurrence in patients with convexity and parasagittal meningiomas according to several predictive factors.
 +
 +
Results: A total of 205 convexity or parasagittal meningioma patients with no other brain disease who underwent one or more contrast-enhanced brain MRIs were enrolled in this 10-year analysis in two hospitals. The optimal cut-off meningioma volume value for prediction of PTBE in all study patients was 13.953 cc (sensitivity = 76.1%; specificity = 92.5%). If a meningioma is assumed to be a complete sphere, 13.953 cc is about 2.987 cm in diameter.
 +
 +
Conclusions: Our study suggests a cut-off value of 3 cm meningioma diameter for prediction of PTBE in patients with convexity and parasagittal meningiomas. We believe that we have revealed why the meningioma diameter of 3 cm is clinically meaningful.
 +
|}
 +
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==Volumetric Analysis of Mucous Retention Cysts in the Maxillary Sinus: A Retrospective Study Using Cone-Beam Computed Tomography==
 +
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{| width="100%"
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34235057 Imaging Sci Dent. 2021 Jun;51(2):117-127. PMID: 34235057] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8219453/pdf/isd-51-117.pdf PDF]
 +
 +
'''Authors:''' Hung K, Hui L, Yeung AWK, Wu Y, Hsung RT, Bornstein MM.
 +
 +
'''Institution:''' Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong.
 +
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'''Abstract:''' cysts (MRCs) in the maxillary sinus and to analyze potential associations of MRCs with dentoalveolar pathologies.
 +
 +
Materials and methods: Cone-beam computed tomography (CBCT) scans exhibiting bilateral maxillary sinuses that were acquired from January 2016 to February 2019 were initially screened. A total of 227 scans (454 sinuses) that fulfilled the inclusion criteria were included. The presence, location, and volumetric characteristics of the diagnosed MRCs were evaluated on CBCT images using the [http://www.slicer.org '''3D Slicer'''] software platform. The presence of MRCs was correlated with potential influencing factors including age, sex, and dentoalveolar pathology. For MRCs located on the sinus floor, factors with a potential impact on the volume, surface, and diameter were analyzed.
 +
 +
Results: An MRC was present in 130 (28.6%) of the 454 sinuses. Most MRCs were located on the sinus walls and floor. The mean MRC volume, surface, and diameter were 551.21±1368.04 mm3, 228.09±437.56 mm2, and 9.63±5.40 mm, respectively. Significantly more sinuses with associated endodontically treated teeth/periapical lesions were diagnosed with an MRC located on the sinus floor. For MRCs located on the sinus floor, endodontic status exhibited a significant association with increased volume, surface, and diameter.
 +
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Conclusion: Periapical lesions might be a contributing factor associated with the presence and volume of MRCs located on the sinus floor. The [http://www.slicer.org '''3D Slicer'''] software platform was found to be a useful tool for clinicians to analyze the size of MRCs before surgical interventions such as sinus floor elevation procedures.
 
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'''Abstract:''' Maxillary transverse deficiency is a common skeletal problem. When the patient is younger, it is treated by rapid palatal expansion by using orthodontic appliances. If this fails or the patient is older, which means skeletal growth is completed, surgically aided rapid palatal expansion (SARPE) becomes necessary. In this technique, after the osteotomies have been made, the two maxillary bones are distracted by tooth-borne device. Since a tooth-borne device will apply the distraction forces on the teeth, the pulp volumes may change. Our aim was to investigate the volume changes of the tooth pulps after SARPE in which a tooth-borne device was used. We scanned our database and included 20 patients (7 males and 13 females) aging between 16 and 30 (mean 19.5±3.97) to this retrospective study. All the patients had undergone SARPE surgeries and they had pre-surgery and postconsolidation cone beam computerized tomography (CBCT) images. All the surgeries had been done in similar ways; all the patients had used similar tooth-borne modified acrylic bonded expansion device. We divided the maxillary teeth into three groups: the incisors, the premolars and the molars. We imported the CBCT images of each patient into [http://www.slicer.org '''3D Slicer'''] software. We calculated volumes of pulps for all maxillary teeth. We compared volumes with paired t test. Statistical significance level was accepted as P< .05. The devices had been left in place between 83 and 179 days including distraction and consolidation periods (mean 121.35±27.83 days). Amount of the expansions varied between 6.03mm and 11.16mm (mean 7.19±1.18mm). We found a statistically significant decrease of the pulp volumes in incisor, premolar and molar teeth (P<.001) between pre-surgery and postconsolidation periods. When using tooth-borne devices in SARPE, their impacts on teeth pulps should also be considered.
 
'''Abstract:''' Maxillary transverse deficiency is a common skeletal problem. When the patient is younger, it is treated by rapid palatal expansion by using orthodontic appliances. If this fails or the patient is older, which means skeletal growth is completed, surgically aided rapid palatal expansion (SARPE) becomes necessary. In this technique, after the osteotomies have been made, the two maxillary bones are distracted by tooth-borne device. Since a tooth-borne device will apply the distraction forces on the teeth, the pulp volumes may change. Our aim was to investigate the volume changes of the tooth pulps after SARPE in which a tooth-borne device was used. We scanned our database and included 20 patients (7 males and 13 females) aging between 16 and 30 (mean 19.5±3.97) to this retrospective study. All the patients had undergone SARPE surgeries and they had pre-surgery and postconsolidation cone beam computerized tomography (CBCT) images. All the surgeries had been done in similar ways; all the patients had used similar tooth-borne modified acrylic bonded expansion device. We divided the maxillary teeth into three groups: the incisors, the premolars and the molars. We imported the CBCT images of each patient into [http://www.slicer.org '''3D Slicer'''] software. We calculated volumes of pulps for all maxillary teeth. We compared volumes with paired t test. Statistical significance level was accepted as P< .05. The devices had been left in place between 83 and 179 days including distraction and consolidation periods (mean 121.35±27.83 days). Amount of the expansions varied between 6.03mm and 11.16mm (mean 7.19±1.18mm). We found a statistically significant decrease of the pulp volumes in incisor, premolar and molar teeth (P<.001) between pre-surgery and postconsolidation periods. When using tooth-borne devices in SARPE, their impacts on teeth pulps should also be considered.
 
|}
 
 
==Association of Regional White Matter Hyperintensity Volumes with Cognitive Dysfunction and Vascular Risk Factors In Patients With Amnestic Mild Cognitive Impairment==
 
 
{| width="100%"
 
|
 
'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34105230 Geriatr Gerontol Int. 2021 Jun 9. PMID: 34105230]
 
 
'''Authors:''' Hirao K, Yamashita F, Sakurai S, 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:''' White matter hyperintensities (WMH) obtained by magnetic resonance imaging (MRI) have been reported to promote neurodegeneration and cognitive decline in patients with mild cognitive impairment (MCI). However, little is known about the association between regional WMH (rWMH) and cognitive dysfunction in MCI. We hence investigated the associations between rWMH volumes and cognitive dysfunction in MCI.
 
 
PVH and DWMH lesions were outlined by a neurologist, using the semiautomated freeware [https://www.slicer.org '''3D Slicer'''], which is a freely available, open-source software package for the visualization, registration, segmentation, and quantification of medical data.
 
|}
 
 
==Association Between Tumor Size and Peritumoral Brain Edema in Patients With Convexity and Parasagittal Meningiomas==
 
 
{| width="100%"
 
|
 
'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/34111188 PLoS One. 2021 Jun 10;16(6):e0252945. PMID: 34111188] | [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8191970/pdf/pone.0252945.pdf PDF]
 
 
'''Authors:''' Shin C, Kim JM, Cheong JH, Ryu JI, Won YD, Ko Y, Han MH.
 
 
'''Institution:''' Department of Neurosurgery, Hanyang University Guri Hospital, Guri, Gyonggi-do, Korea.
 
 
'''Abstract:''' Peritumoral brain edema (PTBE) is a common complication in meningioma and disruption of the tumor-brain barrier in meningioma is crucial for PTBE formation. To evaluate the association between meningioma size and PTBE, we measured meningioma volumes using the [http://www.slicer.org '''3D Slicer'''] in patients with convexity and parasagittal meningiomas.
 
  
 
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Line 486: Line 997:
 
'''Abstract:''' We reviewed imaging and clinical data of 25 patients with a first episode of optic neuritis (ON) (14 females, 11 males; 5 bilateral ON; 7 left ON; 13 right ON). All patients underwent a complete ophthalmological assessment, including visual acuity and RNFL, neurological evaluation, orbits MRI. Segmentation of the optic nerves was performed through [http://www.slicer.org '''3D Slicer'''] open software to get radiomics analysis. All patients underwent a complete neuro-ophthalmological follow-up at 6 months to assess the VO, classified as: complete recovery, partial recovery, deficit persistence/relapse, or visual worsening and were diagnosed as MS or clinically isolated syndrome.
 
'''Abstract:''' We reviewed imaging and clinical data of 25 patients with a first episode of optic neuritis (ON) (14 females, 11 males; 5 bilateral ON; 7 left ON; 13 right ON). All patients underwent a complete ophthalmological assessment, including visual acuity and RNFL, neurological evaluation, orbits MRI. Segmentation of the optic nerves was performed through [http://www.slicer.org '''3D Slicer'''] open software to get radiomics analysis. All patients underwent a complete neuro-ophthalmological follow-up at 6 months to assess the VO, classified as: complete recovery, partial recovery, deficit persistence/relapse, or visual worsening and were diagnosed as MS or clinically isolated syndrome.
  
|}
 
 
==Novel 3D MRI Technique to Measure Perineal Membrane Structural Changes With Pregnancy and Childbirth: Technique Development and Measurement Feasibility==
 
 
{| width="100%"
 
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33893825 Int Urogynecol J. 2021 Apr 24. PMID: 33893825]
 
 
'''Authors:''' Pipitone F, Swenson CW, DeLancey JOL, Chen L.
 
 
'''Institution:''' Pelvic Floor Research Group, University of Michigan, Ann Arbor, MI, USA.
 
 
'''Abstract:''' Introduction and hypothesis: We aimed to develop and validate a new MRI-based perineal membrane reconstruction and morphological measurement technique, and test its feasibility on nulliparous and parous women to determine the effects of pregnancy and childbirth on the perineal membrane.
 
 
Methods: The perineal membrane was traced on high-resolution MRI using [http://www.slicer.org '''3D Slicer'''] and analyses performed using Rhinoceros 6.0 SR23®. Validation was done by comparing MRI-based perineal membrane reconstruction to dissection measurements in a cadaver. Feasibility of reconstruction was assessed in the following three groups: nulliparous (NP), primiparous women who underwent cesarean delivery (CD), and primiparous women with vaginal delivery (VD). The following parameters were measured: (1) swinging door angle, (2) bony and (3) soft tissue attachment lengths, (4) separation at perineal body level, (5) surface area, and (6) hiatal area. ANOVA and post-hoc comparisons were performed, and the effect sizes (d) were reported.
 
 
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Methods: Patients undergoing MRI for a vertebral lesion were retrospectively analyzed (n = 146, 67 males, 79 females; mean age 63 ± 16 years, range 8-89 years) and constituted the train (n = 100) and internal test cohorts (n = 46). Part of the latter had additional prior exams which constituted a multi-scanner, external test cohort (n = 35). Lesions were labeled as benign or malignant (2-label classification), and benign, primary malignant or metastases (3-label classification) for classification analyses. Features extracted via [http://www.slicer.org '''3D Slicer'''] heterogeneityCAD module (hCAD) and PyRadiomics were independently used to compare different combinations of feature selection methods and ML classifiers (n = 19).
 
Methods: Patients undergoing MRI for a vertebral lesion were retrospectively analyzed (n = 146, 67 males, 79 females; mean age 63 ± 16 years, range 8-89 years) and constituted the train (n = 100) and internal test cohorts (n = 46). Part of the latter had additional prior exams which constituted a multi-scanner, external test cohort (n = 35). Lesions were labeled as benign or malignant (2-label classification), and benign, primary malignant or metastases (3-label classification) for classification analyses. Features extracted via [http://www.slicer.org '''3D Slicer'''] heterogeneityCAD module (hCAD) and PyRadiomics were independently used to compare different combinations of feature selection methods and ML classifiers (n = 19).
  
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==Virtual Planning and CAD/CAM-Assisted Distraction for Maxillary Hypoplasia in Cleft Lip and Palate Patients: Accuracy Evaluation and Clinical Outcome==
 
 
{| width="100%"
 
|
 
'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33906808 J Craniomaxillofac Surg. 2021 Apr 21;S1010-5182(21)00105-0. PMID: 33906808]
 
 
'''Authors:''' Gerbino G, Autorino U, Giaccone E, Novaresio A, Ramieri G.
 
 
'''Institution:''' Division of Maxillofacial Surgery, Città della Salute e della Scienza Hospital, University of Torino, Italy.
 
 
'''Abstract:''' The aim of this prospective study was to report the experience with a specific guided distraction protocol for the treatment of CLP patients with severe midface hypoplasia. From January 2016 to April 2019, six consecutive, non-growing, CLP patients with maxillary hypoplasia underwent a specific distraction protocol based on the use of VSP, CAD/CAM-generated surgical splints, cutting guides, prebent internal maxillary distractors, early removal of distractors, and acute callus manipulation and fixation. STL files for VSP, using multislice CT scans taken preoperatively (T0) and 3 months after distractor removal (T1) were superimposed using the free software [http://www.slicer.org '''3D Slicer'''].
 
|}
 
 
==The Topology of Ventricle Surfaces and Its Application in the Analysis of Hydrocephalic Ventricles: A Proof-of-Concept Study==
 
 
{| width="100%"
 
|
 
'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33860336 Neuroradiology. 2021 Apr 15. PMID: 33860336]
 
 
'''Authors:''' Lo YT, Kumar S, Tan LQ, Lock C, Keong NCH.
 
 
'''Institution:''' Department of Neurosurgery, National Neuroscience Institute, Singapore.
 
 
'''Abstract:''' Twenty-one patients with NPH were recruited from our institution, and 21 healthy controls (HC) and patients with Alzheimer's disease (AD) were identified from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. On T1-weighted fine-cut magnetic resonance sequences, [http://www.slicer.org '''3D Slicer'''] was used to segment the left frontal horn.
 
 
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Line 978: Line 1,448:
 
   
 
   
 
'''Abstract:''' Computed tomography images of pigs were acquired in different body positions (supine, head down at 5° and 10°, right lateral recumbent at 5° and 15°) before and after insufflation. We used a free software, [http://www.slicer.org '''3D Slicer'''], for image analysis. After landmark registration using 10 markers inserted into the pelvis, pelvic arterial deformation and shift of seven arterial bifurcation points were evaluated. The distance moved was the target registration error (TRE) from the points registered in the supine position. Fiducial registration error (FRE) was measured using the 10 pelvic markers.
 
'''Abstract:''' Computed tomography images of pigs were acquired in different body positions (supine, head down at 5° and 10°, right lateral recumbent at 5° and 15°) before and after insufflation. We used a free software, [http://www.slicer.org '''3D Slicer'''], for image analysis. After landmark registration using 10 markers inserted into the pelvis, pelvic arterial deformation and shift of seven arterial bifurcation points were evaluated. The distance moved was the target registration error (TRE) from the points registered in the supine position. Fiducial registration error (FRE) was measured using the 10 pelvic markers.
 
|}
 
 
==Development and Validation of a CT-Based Nomogram for Preoperative Prediction of Clear Cell Renal Cell Carcinoma Grades==
 
 
{| width="100%"
 
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'''Publication:''' [https://www.ncbi.nlm.nih.gov/pubmed/33515086 Eur Radiol. 2021 Jan 29. PMID: 33515086]
 
 
'''Authors:''' Zheng Z, Chen Z, Xie Y, Zhong Q, Xie W.
 
 
'''Institution:''' Department of Urology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.
 
 
'''Abstract:''' CT images and clinical data of 258 ccRCC patients were retrieved from the Cancer Imaging Archive (TCIA). Radiomics features were extracted from arterial-phase CT images using [http://www.slicer.org '''3D Slicer'''] software.
 
  
 
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The community that relies on 3D Slicer is large and active: (numbers below updated on October 20st, 2021)

  • 1,269+ 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 in 2021 using 3D Slicer outside of the group that develops it. (Research performed by groups that are also actively developing 3D Slicer is represented in the publication database).


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

2021

A Multicontrast MR Atlas of the Wistar Rat Brain

Publication: Neuroimage. 2021 Nov 15;242:118470. PMID: 34391877 | PDF

Authors: Johnson GA, Laoprasert R, Anderson RJ, Cofer G, Cook J, Pratson F, White LE.

Institution: Center for In Vivo Microscopy, Department of Radiology, Duke University Medical Center, Durham, NC, USA.

Abstract: We describe a multi-contrast, multi-dimensional atlas of the Wistar rat acquired at microscopic spatial resolution using magnetic resonance histology (MRH). Diffusion weighted images, and associated scalar images were acquired of a single specimen with a fully sampled Fourier reconstruction, 61 angles and b=3000 s/mm2 yielding 50 um isotropic spatial resolution. The higher angular sampling allows use of the GQI algorithm improving the angular invariance of the scalar images and yielding an orientation distribution function to assist in delineating subtle boundaries where there are crossing fibers and track density images providing insight into local fiber architecture. A multigradient echo image of the same specimen was acquired at 25 um isotropic spatial resolution. A quantitative susceptibility map enhances fiber architecture relative to the magnitude images. An accompanying multi-specimen atlas (n=6) was acquired with compressed sensing with the same diffusion protocol as used for the single specimen atlas. An average was created using diffeomorphic mapping. Scalar volumes from the diffusion data, a T2* weighted volume, a quantitative susceptibility map, and a track density volume, all registered to the same space provide multiple contrasts to assist in anatomic delineation. The new template provides significantly increased contrast in the scalar DTI images when compared to previous atlases. A compact interactive viewer based on 3D Slicer is provided to facilitate comparison among the contrasts in the multiple volumes. The single volume and average atlas with multiple 3D volumes provide an improved template for anatomic interrogation of the Wistar rat brain. The improved contrast to noise in the scalar DTI images and the addition of other volumes (eg. QA,QSM,TDI ) will facilitate automated label registration for MR histology and preclinical imaging.

Methods for Intratumoral Microdialysis Probe Targeting and Validation in Murine Brain Tumor Models

Publication: J Neurosci Methods. 2021 Nov 1;363:109321. PMID: 34390758

Authors: Rajani K, Olson I, Jacobs JJ, Riviere-Cazaux C, Burns K, Carlstrom L, Schroeder M, Oh J, Howe CL, Rahman M, Sarkaria JN, Elmquist WF, Burns TC.

Institution: Department of Neurologic Surgery, Mayo Clinic, Rochester, MN, USA.

Abstract: Background: Microdialysis is a well validated sampling technique that can be used for pharmacokinetic studies of oncological drugs targeting the central nervous system. This technique has also been applied to evaluate tumor metabolism and identify pharmacodynamic biomarkers of drug activity. Despite the potential utility of microdialysis for therapeutic discovery, variability in tumor size and location hamper routine use of microdialysis as a preclinical tool. Quantitative validation of microdialysis membrane location relative to radiographically evident tumor regions could facilitate rigorous preclinical studies. However, a widely accessible standardized workflow for preclinical catheter placement and validation is needed.

New method: We provide methods for a workflow to yield tailored placement of microdialysis probes within a murine intracranial tumor and illustrate in an IDH1-mutant patient-derived xenograft (PDX) model. This detailed workflow uses a freely available on-line tool built within 3D Slicer freeware to target microdialysis probe placement within the tumor core and validate probe placement fully within the tumor.

Results: We illustrate use of this workflow to validate microdialysis probe location relative to implanted IDH1-mutant PDXs, using the microdialysis probes to quantify levels of extracellular onco-metabolite D-2 hydroxyglutarate.

Comparison with existing methods: Previous methods have used 3D Slicer to reliably measure tumor volumes. Prior microdialysis studies have targeted expected tumor locations without validation.

Conclusions: The new method offers a streamlined and freely available workflow in 3D Slicer to optimize and validate microdialysis probe placement within a murine brain tumor.

Testing the Reliability of CT Scan-Based Dental Wear Magnitude Scoring

Publication: Am J Phys Anthropol. 2021 Nov;176(3):521-7. PMID: 34297351

Authors: Godinho RM, Gonçalves C.

Institution: Interdisciplinary Center for Archaeology and Evolution of Human Behaviour (ICArHEB), Faculdade das Ciências Humanas e Sociais, Universidade do Algarve, Campus Gambelas, Faro, Portugal.

Abstract: Objectives: Digital models are now frequently used in biological anthropology (bioanthropology) research. Despite several studies validating this type of research, none has examined if the assessment of dental wear magnitude based on Computerized Tomography (CT) scans is reliable. Thus, this study aims to fill this gap and assess if dental wear magnitude scoring based on CT scans provides results consistent with scoring based on direct observation of the physical specimens.

Materials and methods: Dental wear magnitude from 412 teeth of 35 mandibles originating from the Portuguese Muge and Sado Mesolithic shell-middens was scored. The mandibles were also CT scanned and visualized using 3D Slicer. CT scan-based scoring of dental wear magnitude was then undertaken. Two scoring rounds were undertaken for each observation method (totaling four scoring rounds) and an intra-observer error test was performed. The averaged results of the two observation methods were compared via boxplots with paired cases.

Results: Intra-observer error was negligible and non-significant. Scoring results are comparable between the two observation methods. Notwithstanding, some differences were found, in which CT scan assessment generally overestimates dental wear when compared to direct observation.

Discussion: Our results generally validate the use of CT scans in studies of dental wear magnitude. Notwithstanding several caveats relating to CT scanning and visualization limitations should be considered to avoid over or under-estimation of dental wear.

The Topology of Ventricle Surfaces and Its Application in the Analysis of Hydrocephalic Ventricles: A Proof-of-Concept Study

Publication: Neuroradiology. 2021 Oct;63(10):1689-99. PMID: 33860336

Authors: Lo YT, Kumar S, Tan LQ, Lock C, Keong NCH.

Institution: Department of Neurosurgery, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore.

Abstract: Purpose: The cerebral ventricles deform in a non-uniform fashion in response to increased CSF volume and/or pressure in hydrocephalic syndromes. Current research is focused on volumetric analyses, while topological analysis of ventricular surfaces remains understudied. We developed a method of quantitatively modeling the curvature of ventricular surfaces to analyze changes in ventricular surfaces in normal pressure hydrocephalus (NPH) and Alzheimer's disease (AD), using the left frontal horn as an example.

Methods: Twenty-one patients with NPH were recruited from our institution, and 21 healthy controls (HC) and patients with Alzheimer's disease (AD) were identified from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. On T1-weighted fine-cut magnetic resonance sequences, 3D Slicer was used to segment the left frontal horn. Next, the mean curvatures at a set of points on the ventricular surface were determined. The frontal horns were scaled and centered into normalized volumes, allowing for pooling across the study subjects. The frontal horn was divided into superolateral, superomedial, inferolateral, and inferomedial surfaces, and locoregional mean curvatures were analyzed. Statistical comparisons were made between NPH, AD, and HC groups.

Results: Significant differences in the mean curvature of lateral surfaces of the ventricles distinguished patterns of distortion between all three cohorts. Significant flattening of the superomedial surface discriminated NPH from HC and AD. However, significant rounding of the inferomedial surface compared to controls was a distinguishing feature of NPH alone.

Conclusion: NPH ventricles deform non-uniformly. The pattern of surface distortion may be used as an additional tool to differentiate between these hydrocephalic conditions.

Prediction of Locoregional Recurrence-Free Survival of Oesophageal Squamous Cell Carcinoma After Chemoradiotherapy Based on an Enhanced CT-Based Radiomics Model

Publication: Front Endocrinol (Lausanne). 2021 Sep 30;12:748997. PMID: 34631575 | PDF

Authors: Kong J, Zhu S, Shi G, Liu Z, Zhang J, Ren J.

Institution: Department of Radiation Oncology, The Fourth Hospital of Hebei Medical University, Shijiazhuang, China.

Abstract: Background and purpose: Chemoradiotherapy is the standard treatment for moderate and advanced oesophageal cancer. The aim of this study was to establish a predictive model based on enhanced computed tomography examination, and to evaluate its clinical value for detecting locoregional recurrence-free survival (LRFS) in cases of oesophageal squamous cell carcinoma after radiotherapy.

Materials and methods: In total, 218 patients with pathologically diagnosed oesophageal squamous cell carcinoma who received radical chemoradiotherapy from July 2016 to December 2017 were collected in this study. Patients were randomly divided into either a training group (n=153) or a validation group (n=65) in a 7:3 ratio. Clinical patient information was then recorded. The enhanced computed tomography scan images of the patients were imported into 3D Slicer v.4.8.1, and the radiomic features were extracted by the Python programme package. In the training group, the dimensionality reduction of the radiomic features was implemented by Lasso regression, and then a radiological label, the model of predicting LRFS, was established and evaluated. To achieve a better prediction performance, the radiological label was combined with clinical risk factor information to construct a radiomics nomogram. A receiver operating characteristic curve was used to evaluate the efficacy of different models. Calibration curves were used to assess the consistency between the predicted and observed recurrence risk, and the Hosmer-Lemeshow method was used to test model fitness. The C-index evaluated the discriminating ability of the prediction model. Decision curve analysis was used to determine the clinical value of the constructed prediction model.

Results: Of the 218 patients followed up in this study, 44 patients (28.8%) in the training group and 21 patients (32.3%) in the validation group experienced recurrence. There was no difference in LRFS between the two groups (χ2 = 0.525, P=0.405). Lasso regression was used in the training group to select six significant radiomic features. The radiological label established using these six features had a satisfactory prediction performance. The C-index was 0.716 (95% CI: 0.645-0.787) in the training group and 0.718 (95% CI: 0.612-0.825) in the validation group. The radiomics nomogram, which included the radiological label and clinical risk factors, achieved a better prediction than the radiological label alone. The C-index was 0.742 (95% CI: 0.674-0.810) in the training group and 0.715 (95% CI: 0.609-0.820) in the validation group. The results of the calibration curve and decision curve analyses indicated that the radiomics nomogram was superior in predicting LRFS of oesophageal carcinoma after radiotherapy.

Conclusions: A radiological label was successfully established to predict the LRFS of oesophageal squamous cell carcinoma after radiotherapy. The radiomics nomogram was complementary to the clinical prognostic features and could improve the prediction of the LRFS after radiotherapy for oesophageal cancer.

Prediction of the Recurrence of Non-Functioning Pituitary Adenomas Using Preoperative Supra-Intra Sellar Volume and Tumor-Carotid Distance

Publication: Front Endocrinol (Lausanne). 2021 Sep 30;12:748997. PMID: 34659129 | PDF

Authors: Chen W, Wang M, Duan C, Yao S, Jiao H, Wang Z, Hu B, Mao Z, Zhu Y, Wang H.

Institution: Center for Pituitary Surgery, Department of Neurosurgery, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

Abstract: Background: Currently, it is difficult to estimate the possibility of recurrence of nonfunctioning pituitary adenomas (NFPAs). Markers such as Ki-67 or transcription factors rely on postoperative pathology, while few indices can be used for preoperative prediction. Therefore, we aimed to investigate the predictive effectiveness of supra-intrasellar volume and tumor-carotid distance based on measurements derived from preoperative magnetic resonance imaging (MRI) data.

Method: Ninety-eight cases of NFPAs were evaluated, along with their clinical characteristics and MRI features. Four radiologic indices were analyzed, including intrasellar tumor volume, suprasellar tumor volume, maximum horizontal tumor diameter, and intercarotid distance. The ratio of supra-intrasellar volume and ratio of tumor-carotid distance were measured using 3D Slicer software, and the sum of two ratios was defined as the V-D value. The correlation between recurrence and multiple factors was analyzed using univariate and multivariate logistic regression and Kaplan-Meier analysis, and ROC curves were used to estimate the prognostic performance of radiologic measurements in NFPAs.

Result: The supra-intrasellar volume ratio, tumor-carotid distance ratio and V-D value were significantly correlated with the recurrence of NFPAs. The predictive importance of the V-D value reached 84.5%, with a sensitivity of 83.7% and specificity of 67.3%. The cutoff limit of the V-D value was 1.53, and patients with V-D values higher than 1.53 tended to relapse much earlier.

Conclusion: The V-D value has predictive importance for the recurrence of NFPAs preoperatively. Patients with higher V-D values will undergo recurrence earlier and should be given greater consideration in terms of surgery and follow-up time.

Analysis of Changes in the Volume of Edema Around Brain Contusions and the Influencing Factors: A Single-Center, Retrospective, Observational Study

Publication: Medicine (Baltimore). 2021 Sep 24;100(38):e27246. PMID: 34559127 | PDF

Authors: Liu HB, Xu WM, Wang SS, Wei LF, Hong JF, Wang C, Xian L.

Institution: Department of Neurosurgery of the 900th Hospital, Fuzong Clinical Medical School of Fujian Medical University, Fuzhou, Fujian Province, China.

Abstract: Traumatic brain injury (TBI), a common neurosurgical condition, has well-known treatment guidelines. However, the mechanisms underlying the varying severity of brain edema secondary to TBI are largely unknown, leading to controversial treatments.This study seeks to measure edema volumes around brain contusions in different regions, analyze factors related to differences in edema volume and provide a theoretical basis for brain edema treatment.Data from 113 brain contusion patients treated at the Department of Neurosurgery of Fuzhou General Hospital from January 2017 to November 2019 were analyzed retrospectively. Based on computed tomography (CT) data, the patients were divided into the venous group (brain contusion in regions with large cortical veins, n = 47) and the nonvenous group (brain contusions in other regions, n = 66). Here, 3D Slicer software was used to calculate the brain contusion volume on the first CT obtained after injury and the brain contusion volume and its surrounding edema on the 5th day after injury. The brain contusion volume to surrounding edema volume ratio was calculated, and the number of patients who showed brain contusion progression requiring surgery was determined. Hematocrit (Hct), fibrinogen (Fg), and d-dimer levels within 6 hours and on the 5th day after admission were also compared.Patients in the venous group had a significantly increased percentage of area with edema around the brain contusion compared with patients in the nonvenous group (P < .05), and the 2 groups showed no significant difference in the number of patients with brain contusion progression or surgical treatment (P > .05) or Hct, Fg, or d-dimer (D-D) levels. For all patients, Hct, Fg, and D-D levels within 6 hours after admission were significantly different from those on the 5th day (P < .05 for all).Cortical venous obstruction may be the most important factor influencing edema around brain contusions. The Fg level decreased slightly, and the D-D level increased to its peak rapidly after mild-moderate TBI. This change was followed by a gradual increase in the former and a gradual decrease in the latter.

Hybrid Additive Fabrication of a Transparent Liver with Biosimilar Haptic Response for Preoperative Planning

Publication: Diagnostics (Basel). 2021 Sep 21;11(9):1734. PMID: 34574075 | PDF

Authors: Aseni P, Santaniello T, Rizzetto F, Gentili L, Pezzotta F, Cavaliere F, Vertemati M, Milani P.

Institution: Department of Emergency, ASST Grande Ospedale Metropolitano Niguarda, Milano, Italy.

Abstract: Due to the complexity of liver surgery, the interest in 3D printing is constantly increasing among hepatobiliary surgeons. The aim of this study was to produce a patient-specific transparent life-sized liver model with tissue-like haptic properties by combining additive manufacturing and 3D moulding. A multistep pipeline was adopted to obtain accurate 3D printable models. Semiautomatic segmentation and registration of routine medical imaging using 3D Slicer software allowed to obtain digital objects representing the structures of interest (liver parenchyma, vasculo-biliary branching, and intrahepatic lesion). The virtual models were used as the source data for a hybrid fabrication process based on additive manufacturing using soft resins and casting of tissue-mimicking silicone-based blend into 3D moulds. The model of the haptic liver reproduced with high fidelity the vasculo-biliary branching and the relationship with the intrahepatic lesion embedded into the transparent parenchyma. It offered high-quality haptic perception and a remarkable degree of surgical and anatomical information. Our 3D transparent model with haptic properties can help surgeons understand the spatial changes of intrahepatic structures during surgical manoeuvres, optimising preoperative surgical planning.

The Impact of Tumor Edema on T2-Weighted 3T-MRI Invasive Breast Cancer Histological Characterization: A Pilot Radiomics Study

Publication: Cancers (Basel). 2021 Sep 15;13(18):4635. PMID: 34572862 | PDF

Authors: Santucci D, Faiella E, Cordelli E, Calabrese A, Landi R, de Felice C, Beomonte Zobel B, Grasso RF, Iannello G, Soda P.

Institution: Department of Radiology, University of Rome "Campus Bio-Medico", Roma, Italy.

Abstract: Background: to evaluate the contribution of edema associated with histological features to the prediction of breast cancer (BC) prognosis using T2-weighted MRI radiomics.

Methods: 160 patients who underwent staging 3T-MRI from January 2015 to January 2019, with 164 histologically proven invasive BC lesions, were retrospectively reviewed. Patient data (age, menopausal status, family history, hormone therapy), tumor MRI-features (location, margins, enhancement) and histological features (histological type, grading, ER, PgR, HER2, Ki-67 index) were collected. Of the 160 MRI exams, 120 were considered eligible, corresponding to 127 lesions. T2-MRI were used to identify edema, which was classified in four groups: peritumoral, pre-pectoral, subcutaneous, or diffuse. A semi-automatic segmentation of the edema was performed for each lesion, using 3D Slicer open-source software. Main radiomics features were extracted and selected using a wrapper selection method. A Random Forest type classifier was trained to measure the performance of predicting histological factors using semantic features (patient data and MRI features) alone and semantic features associated with edema radiomics features.

Results: edema was absent in 37 lesions and present in 127 (62 peritumoral, 26 pre-pectoral, 16 subcutaneous, 23 diffuse). The AUC-classifier obtained by associating edema radiomics with semantic features was always higher compared to the AUC-classifier obtained from semantic features alone, for all five histological classes prediction (0.645 vs. 0.520 for histological type, 0.789 vs. 0.590 for grading, 0.487 vs. 0.466 for ER, 0.659 vs. 0.546 for PgR, and 0.62 vs. 0.573 for Ki67).

Conclusions: radiomic features extracted from tumor edema contribute significantly to predicting tumor histology, increasing the accuracy obtained from the combination of patient clinical characteristics and breast imaging data.

A Comparative Study Between State-of-the-Art MRI Deidentification and AnonyMI, a New Method Combining Re-Identification Risk Reduction and Geometrical Preservation

Publication: Hum Brain Mapp. 2021 Sep 14 PMID: 34520074

Authors: Mikulan E, Russo S, Zauli FM, d'Orio P, Parmigiani S, Favaro J, Knight W, Squarza S, Perri P, Cardinale F, Avanzini P, Pigorini A.

Institution: Dipartimento di Scienze Biomediche e Cliniche "L.Sacco", Università degli Studi di Milano, Milano, Italy.

Abstract: Deidentifying MRIs constitutes an imperative challenge, as it aims at precluding the possibility of re-identification of a research subject or patient, but at the same time it should preserve as much geometrical information as possible, in order to maximize data reusability and to facilitate interoperability. Although several deidentification methods exist, no comprehensive and comparative evaluation of deidentification performance has been carried out across them. Moreover, the possible ways these methods can compromise subsequent analysis has not been exhaustively tested. To tackle these issues, we developed AnonyMI, a novel MRI deidentification method, implemented as a user-friendly 3D Slicer plugin-in, which aims at providing a balance between identity protection and geometrical preservation. To test these features, we performed two series of analyses on which we compared AnonyMI to other two state-of-the-art methods, to evaluate, at the same time, how efficient they are at deidentifying MRIs and how much they affect subsequent analyses, with particular emphasis on source localization procedures. Our results show that all three methods significantly reduce the re-identification risk but AnonyMI provides the best geometrical conservation. Notably, it also offers several technical advantages such as a user-friendly interface, multiple input-output capabilities, the possibility of being tailored to specific needs, batch processing and efficient visualization for quality assurance.

Three-Dimensional Structure of the Basal Lamella of the Middle Turbinate

Publication: Sci Rep. 2021 Sep 9;11(1):17960. PMID: 34504200 | PDF

Authors: Eördögh M, Baksa G, Grimm A, Bárány L, Petneházy Ö, Reisch R, Schroeder HWS, Briner HR, Hosemann W.

Institution: Department of Neurosurgery, University Medicine Greifswald, Sauerbruchstraße, Greifswald, Germany.

Abstract: The middle turbinate's basal lamella (3BL) is a variable landmark which needs to be understood in endoscopic transnasal skull base surgery. It comprises an anterior frontal and a posterior horizontal part and appears in its simplest depiction to be "L"-shaped, when viewed laterally. In this study we analyzed its 3D morphology and variations focusing on a precise and systematic description of the anatomy. CBCTs of 25 adults, 19 cadavers and 6 skulls (total: 100 sides) were investigated with the 3D Slicer software, creating 3D models of the 3BL. We introduced a novel geometrical classification of the 3BL's shape, based on segments. We analyzed their parameters and relationship to neighboring structures. When viewed laterally, there was no consistent "L"-shaped appearance of the 3BL, as it is frequently quoted. A classification of 9 segment types was used to describe the 3BL. The 3BLs had in average of 2.95 ± 0.70 segments (median: 3), the most frequent was the horizontal plate (23.05% of all segments), next a concave/convex plate (22.71%), then a sigma plate (22.37%). Further types were rare. We identified a horizontal plate in 68% of all lateral views whilst 32% of the 3BLs were vertical. A sigma-concave/convex-horizontal trisegmental 3BL was the most common phenotype (27%). Globally, the sigma-concave/convex pattern was present in 42%. The 3BL adhered the ethmoidal bulla in 87%. The segmenting method is eligible to describe the 3BL's sophisticated morphology.

Flatness of the Meckel Cave May Cause Primary Trigeminal Neuralgia: A Radiomics-Based Study

Publication: J Headache Pain. 2021 Sep 3;22(1):104. PMID: 34479476 | PDF

Authors: Lin J, Zhang Y, Li W, Yan J, Ke Y.

Institution: Department of Neurosurgery, Guangdong Second Provincial General Hospital, Guangzhou, China.

Abstract: Background: Neurovascular contact (NVC) is the main cause of primary trigeminal neuralgia (PTN); however, cases of PTN without NVC are still observed. In this study, the Meckel cave (MC) morphology in PTN were analyzed by radiomics and compared to healthy controls (HCs) to explore the cause of PTN.

Methods: We studied the 3.0T MRI data of 115 patients with PTN and 46 HCs. Bilateral MC was modeled using the 3D Slicer software, and the morphological characteristics of MC were analyzed using the radiomics method.

Results: The right side incidence rate in the PTN group was higher than the left side incidence. By analyzing the flatness feature of MC, we observed that the affected side of the PTN was lower than that of the unaffected side, the right MC of the PTN and HC was lower than that of the left MC, the MC of the affected side of the left and right PTN without bilateral NVC was lower than that of the unaffected side.

Conclusions: By providing a method to analyze the morphology of the MC, we found that there is an asymmetry in the morphology of bilateral MC in the PTN and HC groups. It can be inferred that the flatness of the MC may be a cause of PTN.

An Unsupervised Learning Approach to Ultrasound Strain Elastography With Spatio-Temporal Consistency

Publication: Phys Med Biol. 2021 Sep 3;66(17):175031. PMID: 34298531 | PDF

Authors: Delaunay R, Hu Y, Vercauteren T.

Institution: Wellcome/EPSRC Centre for Interventional and Surgical Sciences, University College London, London, UK.

Abstract: Quasi-static ultrasound elastography (USE) is an imaging modality that measures deformation (i.e. strain) of tissue in response to an applied mechanical force. In USE, the strain modulus is traditionally obtained by deriving the displacement field estimated between a pair of radio-frequency data. In this work we propose a recurrent network architecture with convolutional long-short-term memory decoder blocks to improve displacement estimation and spatio-temporal continuity between time series ultrasound frames. The network is trained in an unsupervised way, by optimising a similarity metric between the reference and compressed image. Our training loss is also composed of a regularisation term that preserves displacement continuity by directly optimising the strain smoothness, and a temporal continuity term that enforces consistency between successive strain predictions. In addition, we propose an open-accessin vivodatabase for quasi-static USE, which consists of radio-frequency data sequences captured on the arm of a human volunteer. Our results from numerical simulation andin vivodata suggest that our recurrent neural network can account for larger deformations, as compared with two other feed-forward neural networks. In all experiments, our recurrent network outperformed the state-of-the-art for both learning-based and optimisation-based methods, in terms of elastographic signal-to-noise ratio, strain consistency, and image similarity. Finally, our open-source code provides a 3D Slicer visualisation module that can be used to process ultrasound RF frames in real-time, at a rate of up to 20 frames per second, using a standard GPU.

A Mandible with the Temporomandibular Joint-A New FEM Model Dedicated to Strength and Fatigue Calculations of Bonding Elements Used in Fracture and Defect Surgery

Publication: Materials (Basel). 2021 Sep 2;14(17):5031. PMID: 34501120 | PDF

Authors: Mańkowski J, Piękoś J, Dominiak K, Klukowski P, Fotek M, Zawisza M, Żach P.

Institution: Institute of Machine Design Fundamentals, Warsaw University of Technology, Warsaw, Poland.

Abstract: The aim of the study was to develop a new FEM (finite element method) model of a mandible with the temporal joint, which can be used in the numerical verification of the work of bonding elements used in surgical operations of patients with mandibular fractures or defects. Most of such types of numerical models are dedicated to a specific case. The authors engaged themselves in building a model that can be relatively easily adapted to various types of tasks, allowing to assess stiffness, strength and durability of the bonded fragments, taking into account operational loads and fatigue limit that vary in time. The source of data constituting the basis for the construction of the model were DICOM (digital imaging and communications in medicine) files from medical imaging using computed tomography. On their basis, using the 3D Slicer program and algorithms based on the Hounsfield scale, a 3D model was created in the STL (standard triangle language) format. A CAD (computer-aided design) model was created using VRMesh and SolidWorks. An FEM model was built using HyperWorks and Abaqus/CAE. Abaqus solver was used for FEM analyses. A model meeting the adopted assumptions was built. The verification was conducted by analyzing the influence of the simplifications of the temporomandibular joint in the assessment of mandibular strain. The work of an undamaged mandible and the work of the bonded fracture of the mandible were simulated.

Mini Hyrax vs Hyrax Expanders in the Rapid Palatal Expansion in Adolescents With Posterior Crossbite: A Randomized Controlled Clinical Trial

Publication: Prog Orthod. 2021 Sep 1;22(1):30. PMID: 34467450 | PDF

Authors: Silveira GS, Abreu LG, Palomo JM, da Matta Cid Pinto LS, de Sousa AA, Gribel BF, Oliveira DD.

Institution: School of Dentistry, Pontifical Catholic University of Minas Gerais, Belo Horizonte, MG, Brazil.

Abstract: Purpose: The aim of this study was to compare the dental effects, impact on quality of life, and pain perception of adolescents wearing Mini Hyrax and Hyrax expanders in rapid palatal expansion.

Methods: Thirty-four adolescents aged 11 to 16 years, with maxillary transverse deficiency (unilateral or bilateral posterior crossbite), were randomly allocated into two groups, Mini Hyrax group and Hyrax group (1:1 ratio). Dental effects were evaluated by digitally superimposed pretreatment and postretention three-dimensional intraoral scans on the palatal rugaes using the software 3D Slicer. Impact on quality of life was assessed with the OHIP-14 questionnaire applied in the pretreatment, posttreatment and postretention. Visual analog scale was applied 24, 48, and 72 h and 7 days after the first activation of the expander.

Results: Thirty of the 34 adolescents recruited completed the study. There were no statistically significant differences in dentoalveolar effects between groups. OHIP-14 scores across time among Mini Hyrax wearers were similar to those of the Hyrax wearers. The inter-group comparisons showed no difference between groups with respect to the OHIP-14 scores in posttreatment and postretention (p > 0.05). There were no differences in pain perception between groups. Considering intra-group comparison, the reduction in pain perception among adolescents in the Mini Hyrax group was gradual. Among adolescents in the Hyrax group, a statistically significant reduction between 48 and 72 h was observed.

Conclusion: There were no significant differences in dental effects, impact on quality of life and pain perception between adolescents wearing Mini Hyrax and Hyrax expanders in rapid palatal expansion.

A Novel Dynamic Electromagnetic Tracking Navigation System for Distal Locking of Intramedullary Nails

Publication: Comput Methods Programs Biomed. 2021 Sep;209:106326. PMID: 34433127

Authors: Gao Y, Wang H, Tu P, Hu J, Wang Q, Chen X.

Institution: School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China.

Abstract: Background: The accurate distal locking of intramedullary (IM) nails is a clinical challenge for surgeons. Although many navigation systems have been developed, a real-time guide method with free radiation exposure, better user convenience, and high cost performance has not been proposed.

Methods: This paper aims to develop an electromagnetic navigation system named TianXuan-MDTS that provides surgeons with a proven surgical solution. And the registration method with external landmarks for IM nails and calibration algorithm for guiders were proposed. A puncture experiment, model experiments measured by 3D Slicer and cadaver experiments (2 cadaveric leg specimens and 6 drilling operations) are conducted to evaluate its performance and stability.

Results: The registration deviations (TRE) is 1.05± 0.13 mm. In the puncture experiment, a success rate of 96% can be achieved in 45.94 s. TianXuan-MDTS were evaluated on 3 tibia model. The results demonstrated that all 9 screw holes were successfully prepared at a rate of 100% in 91.67 s. And the entry point, end point, and angular deviations were 1.60±0.20 mm, 1.47±0.18 mm, and 3.10±0.84°, respectively. Postoperative fluoroscopy in cadaver experiments showed that all drills were in the distal locking holes, with a success rate of 100% and the average time 143.17± 18.27s.

Conclusions: The experimental results indicate that our system with novel registration and calibration methods could serve as a feasible and promising tool to assist surgeons during distal locking.


TorchIO: A Python Library for Efficient Loading, Preprocessing, Augmentation and Patch-Based Sampling of Medical Images in Deep Learning

Publication: Comput Methods Programs Biomed. 2021 Sep;208:106236. PMID: 34311413

Authors: Pérez-García F, Sparks R, Ourselin S.

Institution: Department of Medical Physics and Biomedical Engineering, University College London, UK.

Abstract: Background and objective: Processing of medical images such as MRI or CT presents different challenges compared to RGB images typically used in computer vision. These include a lack of labels for large datasets, high computational costs, and the need of metadata to describe the physical properties of voxels. Data augmentation is used to artificially increase the size of the training datasets. Training with image subvolumes or patches decreases the need for computational power. Spatial metadata needs to be carefully taken into account in order to ensure a correct alignment and orientation of volumes.

Methods: We present TorchIO, an open-source Python library to enable efficient loading, preprocessing, augmentation and patch-based sampling of medical images for deep learning. TorchIO follows the style of PyTorch and integrates standard medical image processing libraries to efficiently process images during training of neural networks. TorchIO transforms can be easily composed, reproduced, traced and extended. Most transforms can be inverted, making the library suitable for test-time augmentation and estimation of aleatoric uncertainty in the context of segmentation. We provide multiple generic preprocessing and augmentation operations as well as simulation of MRI-specific artifacts.

Results: Source code, comprehensive tutorials and extensive documentation for TorchIO can be found at http://torchio.rtfd.io/. The package can be installed from the Python Package Index (PyPI) running pip install torchio. It includes a command-line interface which allows users to apply transforms to image files without using Python. Additionally, we provide a graphical user interface within a TorchIO extension in 3D Slicer to visualize the effects of transforms.

Conclusion: TorchIO was developed to help researchers standardize medical image processing pipelines and allow them to focus on the deep learning experiments. It encourages good open-science practices, as it supports experiment reproducibility and is version-controlled so that the software can be cited precisely. Due to its modularity, the library is compatible with other frameworks for deep learning with medical images.

Virtual Planning and CAD/CAM-Assisted Distraction for Maxillary Hypoplasia in Cleft Lip and Palate Patients: Accuracy Evaluation and Clinical Outcome

Publication: J Craniomaxillofac Surg. 2021 Sep;49(9):799-808 PMID: 33906808

Authors: Gerbino G, Autorino U, Giaccone E, Novaresio A, Ramieri G.

Institution: Division of Maxillofacial Surgery, Città della Salute e della Scienza Hospital, University of Torino, Italy.

Abstract: The aim of this prospective study was to report the experience with a specific guided distraction protocol for the treatment of CLP patients with severe midface hypoplasia. From January 2016 to April 2019, six consecutive, non-growing, CLP patients with maxillary hypoplasia underwent a specific distraction protocol based on the use of VSP, CAD/CAM-generated surgical splints, cutting guides, prebent internal maxillary distractors, early removal of distractors, and acute callus manipulation and fixation. STL files for VSP, using multislice CT scans taken preoperatively (T0) and 3 months after distractor removal (T1) were superimposed using the free software 3D Slicer and Geomagic Wrap to evaluate the accuracy of maxillary repositioning and assess 3D bone changes. Clinical outcome was evaluated at the 1-year follow-up (T2). The patients and surgeon were satisfied with the occlusal and aesthetic outcomes. A maximum difference of 2 mm between the VSP and the actual surgical outcome was chosen as the success criterion for accuracy. The average linear difference for selected points was <2 mm in four patients and >2 mm in two patients. The average distance of the postoperative maxilla from the VSP model was 2.28 mm (median 1.85), while the average forward movement of the maxilla was 10.18 mm The protocol used is effective and accurate in the correction of severe maxillary hypoplasia in CLP patients. Early removal of the distractor and stabilization with plates reduces patient discomfort and does not jeopardize stability. This protocol should be reserved for complex cases due to the costs of the procedure, which are not negligible.

Novel 3D MRI Technique to Measure Perineal Membrane Structural Changes With Pregnancy and Childbirth: Technique Development and Measurement Feasibility

Publication: Int Urogynecol J. 2021 Sep;32(9):2413-20. PMID: 33893825

Authors: Pipitone F, Swenson CW, DeLancey JOL, Chen L.

Institution: Pelvic Floor Research Group, University of Michigan, Ann Arbor, MI, USA.

Abstract: Introduction and hypothesis: We aimed to develop and validate a new MRI-based perineal membrane reconstruction and morphological measurement technique, and test its feasibility on nulliparous and parous women to determine the effects of pregnancy and childbirth on the perineal membrane.

Methods: The perineal membrane was traced on high-resolution MRI using 3D Slicer and analyses performed using Rhinoceros 6.0 SR23®. Validation was done by comparing MRI-based perineal membrane reconstruction to dissection measurements in a cadaver. Feasibility of reconstruction was assessed in the following three groups: nulliparous (NP), primiparous women who underwent cesarean delivery (CD), and primiparous women with vaginal delivery (VD). The following parameters were measured: (1) swinging door angle, (2) bony and (3) soft tissue attachment lengths, (4) separation at perineal body level, (5) surface area, and (6) hiatal area. ANOVA and post-hoc comparisons were performed, and the effect sizes (d) were reported.

Results: Model reconstruction was similar to cadaver dissection findings. Morphological measurements were feasible in all women (NP, n = 10; CS, n = 6; VD, n = 19). Swinging door angle was 13o greater in CD (p = 0.03; d = 1.15) and 16o greater in VD (p < 0.001; d = 1.41) compared to NP. VD showed 13% larger separation at the perineal body than NP (p = 0.097, d = 0.84) and 23% larger hiatal area than CD (p = 0.14, d = 0.94).

Conclusion: This novel and anatomically validated MRI-based perineal membrane reconstruction technique is feasible. Preliminary findings show that pregnancy and childbirth both influence perineal membrane morphology with VD being associated with the largest swinging door angle and perineal body separation.

A Supplemental Technique for Preoperative Evaluation of Giant Intracranial Aneurysm

Publication: J Neurol Surg A Cent Eur Neurosurg. 2021 Sep;82(5):424-9. PMID: 33583010

Authors: Wang HW, Wu C, Xue Z, Shu XJ, Sun ZH.

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

Abstract: Background: Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in giant intracranial aneurysms (GIAs). In this study, we aimed to reconstruct the circulating and noncirculating parts of GIAs with the time-of-flight (TOF) and motion-sensitized driven-equilibrium (MSDE) sequences with 3D Slicer to reveal an integrated presentation of GIAs, compare its accuracy, and validate the usefulness for preoperative planning.

Material and methods: Patients with GIAs who were treated with microsurgery in our department were included in this study. Both the TOF and MSDE sequence data for each patient were loaded into 3D Slicer for reconstruction and segmentation. The parameters measured by 3D Slicer were compared with those measured by DSA.

Results: The mean diameter for all GIAs was 28.7 ± 1.5 mm (range, 25.9-31.9 mm). The mean diameter for all GIAs measured by DSA and 3D Slicer was 24.46 ± 5.25 and 28.66 ± 1.48 mm, respectively (t = 4.948, p < 0.01). When only the nonthrombotic GIAs were included, the mean diameter measured by DSA and 3D Slicer was 28.69 ± 2.03 and 28.97 ± 1.79 mm, respectively (t = 1.023, p = 0.323). The mean aneurysmal volume was 8,292.6 ± 1,175.1 mm3 and the mean thrombotic volume was 3,590.0 ± 1,003.7 mm3.

Conclusion: The MSDE sequence brings diagnostic benefits as a comparison to other MRI sequences. Reconstruction of GIAs with 3D Slicer is a low-cost, dependable, and useful supplemental technique for surgical planning.

Maxillary Dentoskeletal Outcomes of the Expander With Differential Opening and the Fan-Type Expander: A Randomized Controlled Trial

Publication: Clin Oral Investig. 2021 Sep;25(9):5247-56. PMID: 33580351 | PDF

Authors: Massaro C, Garib D, Cevidanes L, Janson G, Yatabe M, Lauris JRP, Ruellas AC.

Institution: Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, SP, Brazil.

Abstract: Objectives: The aim of this study was to compare the maxillary dentoskeletal outcomes of the expander with differential opening (EDO) and the fan-type expander (FE).

Material and methods: Forty-eight patients with maxillary arch constriction in the mixed dentition were randomly allocated into EDO and FE groups. Cone-beam computed tomography scans were acquired before and after expansion. Linear and angular three-dimensional changes were assessed after cranial base superimposition using the ITK-SNAP and the 3D Slicer software. T or Mann-Whitney U tests were used for intergroup comparisons (P<0.05).

Results: The EDO group comprised 24 patients treated with the EDO (13 female, 11 male; 7.6 years). The FE group comprised 24 patients treated with the FE (14 female, 10 male; 7.8 years). Skeletal lateral displacements were greater in the EDO group with greater expansion in the orbital, nasal cavity, zygomatic bone, and palate regions (mean intergroup differences of 0.4, 0.8, 0.9, and 1.1 mm, respectively). Intercanine expansion and canine buccal inclination were greater in the FE group, while intermolar distance changes and molar buccal inclination were greater in the EDO group. Similar changes were observed for vertical and anteroposterior displacements and palatal plane rotation.

Conclusions: The EDO produced greater transverse skeletal expansion compared to the FE, with similar vertical and anteroposterior effects. Dental changes were greater in the molar region for patients treated with the EDO and in the canine region for patients treated with the FE.

Clinical relevance: The EDO and the FE are capable of producing skeletal changes in the mixed dentition. The decision between both expanders will depend on the amount of expansion required in the molar region and in the nasomaxillary complex.

Utility of Machine Learning of Apparent Diffusion Coefficient (ADC) and T2-Weighted (T2W) Radiomic Features in PI-RADS Version 2.1 Category 3 Lesions to Predict Prostate Cancer Diagnosis

Publication: Abdom Radiol (NY). 2021 Aug 31. PMID: 34467426

Authors: Lim CS, Abreu-Gomez J, Thornhill R, James N, Al Kindi A, Lim AS, Schieda N.

Institution: Department of Medical Imaging, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, ON, Canada.

Abstract: Purpose: To evaluate if machine learning (ML) of radiomic features extracted from apparent diffusion coefficient (ADC) and T2-weighted (T2W) MRI can predict prostate cancer (PCa) diagnosis in Prostate Imaging-Reporting and Data System (PI-RADS) version 2.1 category 3 lesions.

Methods: This multi-institutional review board-approved retrospective case-control study evaluated 158 men with 160 PI-RADS category 3 lesions (79 peripheral zone, 81 transition zone) diagnosed at 3-Tesla MRI with histopathology diagnosis by MRI-TRUS-guided targeted biopsy. A blinded radiologist confirmed PI-RADS v2.1 score and segmented lesions on axial T2W and ADC images using 3D Slicer, extracting radiomic features with an open-source software (Pyradiomics). Diagnostic accuracy for (1) any PCa and (2) clinically significant (CS; International Society of Urogenital Pathology Grade Group ≥ 2) PCa was assessed using XGBoost with tenfold cross -validation.

Results: From 160 PI-RADS 3 lesions, there were 50.0% (80/160) PCa, including 36.3% (29/80) CS-PCa (63.8% [51/80] ISUP 1, 23.8% [19/80] ISUP 2, 8.8% [7/80] ISUP 3, 3.8% [3/80] ISUP 4). The remaining 50.0% (80/160) lesions were benign. ML of all radiomic features from T2W and ADC achieved area under receiver operating characteristic curve (AUC) for diagnosis of (1) CS-PCa 0.547 (95% Confidence Intervals 0.510-0.584) for T2W and 0.684 (CI 0.652-0.715) for ADC and (2) any PCa 0.608 (CI 0.579-0.636) for T2W and 0.642 (CI 0.614-0.0.670) for ADC.

Conclusion: Our results indicate ML of radiomic features extracted from T2W and ADC achieved at best moderate accuracy for determining which PI-RADS category 3 lesions represent PCa.

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

Publication: HNO. 2021 Aug 31. 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.

Pars Triangularis Volume Asymmetry and Schneiderian First Rank Symptoms in Antipsychotic-naïve Schizophrenia

Publication: Clin Psychopharmacol Neurosci. 2021 Aug 31;19(3):507-13. PMID: 34294619| PDF

Authors: Shivakumar V, Sreeraj VS, Kalmady SV, Gangadhar BN, Venkatasubramanian G.

Institution: Department of Integrative Medicine, National Institute of Mental Health & NeuroSciences (NIMHANS), Bangalore, India.

Abstract: Objective: Schizophrenia is a disorder of language and self, with first-rank symptoms (FRS) as one of the predominant features in a subset of patients. Abnormal language lateralization is hypothesized to underlie the neurobiology of FRS in schizophrenia. The role of Broca's area with its right-hemispheric counterpart, consisting of pars triangularis (PTr) and pars opercularis (POp) of the inferior frontal gyrus in FRS is undetermined. We compared the volumes and asymmetries of PTr & POp in anti-psychotic-naive schizophrenia patients with FRS (FRS[+]) with those without FRS (FRS[-]) and healthy-controls (HC) using three dimensional, interactive, semi-automated volumetric morphometry.

Methods: Antipsychotic naïve FRS(+) (n = 27), FRS(-) (n = 24) and HC (n = 51) were carefully assessed with structured and semi-structured clinical tools. T1-weighted images were acquired in a 3T scanner. Volumes of regions of interest were measured independently for both sides using 3D Slicer software, and asymmetry indices were calculated.

Results: FRS(+) but not FRS(-) had a significant volume deficit in right PTr after controlling for the potential confounding effects of age, sex, and intracranial volume (p = 0.029). There was a significant leftward asymmetry of PTr in patients with FRS (i.e., leftward asymmetry in patients) (p = 0.026). No significant volume/asymmetry abnormalities were observed in POp.

Conclusion: Study findings suggest reduced right PTr volume with leftward asymmetry to be associated with FRS in schizophrenia. This is consistent with the loss of Yakovlevian torque in schizophrenia. Role of PTr in the neurobiology of schizophrenia as a disorder of self, speech, and social cognition needs further systematic evaluation in future research.

Stability and Reproducibility of Radiomic Features Based Various Segmentation Technique on MR Images of Hepatocellular Carcinoma (HCC)

Publication: Diagnostics (Basel). 2021 Aug 30;11(9):1573. PMID: 34573915| PDF

Authors: Haniff NSM, Abdul Karim MK, Osman NH, Saripan MI, Che Isa IN, Ibahim MJ.

Institution: Department of Physics, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.

Abstract: Hepatocellular carcinoma (HCC) is considered as a complex liver disease and ranked as the eighth-highest mortality rate with a prevalence of 2.4% in Malaysia. Magnetic resonance imaging (MRI) has been acknowledged for its advantages, a gold technique for diagnosing HCC, and yet the false-negative diagnosis from the examinations is inevitable. In this study, 30 MR images from patients diagnosed with HCC is used to evaluate the robustness of semi-automatic segmentation using the flood fill algorithm for quantitative features extraction. The relevant features were extracted from the segmented MR images of HCC. Four types of features extraction were used for this study, which are tumour intensity, shape feature, textural feature and wavelet feature. A total of 662 radiomic features were extracted from manual and semi-automatic segmentation and compared using intra-class relation coefficient (ICC). Radiomic features extracted using semi-automatic segmentation utilized flood filling algorithm from 3D Slicer had significantly higher reproducibility (average ICC = 0.952 ± 0.009, p < 0.05) compared with features extracted from manual segmentation (average ICC = 0.897 ± 0.011, p > 0.05). Moreover, features extracted from semi-automatic segmentation were more robust compared to manual segmentation. This study shows that semi-automatic segmentation from 3D-Slicer is a better alternative to the manual segmentation, as they can produce more robust and reproducible radiomic features.

Postsurgical Stability of Temporomandibular Joint of Skeletal Class III Patients Treated with 2-Jaw Orthognathic Surgery via Computer-Aided Three-Dimensional Simulation and Navigation in Orthognathic Surgery (CASNOS)

Publication: Biomed Res Int. 2021 Aug 6;2021:1563551. PMID: 34409098| PDF

Authors: Wang LC, Lee YH, Tsai CY, Wu TJ, Teng YY, Lai JP, Lin SS, Chang YJ.

Institution: Department of Craniofacial Orthodontics, Department of Dentistry, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.

Abstract: Objective: The aim of this study is to clarify the postsurgical stability of temporomandibular joints in skeletal class III patients treated with 2-jaw orthognathic surgery which was performed utilizing computer-aided three-dimensional simulation and navigation in orthognathic surgery (CASNOS) protocol.

Materials and methods: 23 consecutive nongrowing skeletal class III patients with mandibular prognathism associated with maxillary retrognathism treated with 2-jaw orthognathic surgery between 2018 and 2019 were enrolled in this study. The surgery was planned according to the standardized protocol of CASNOS (computer-aided three-dimensional simulation and navigation in orthognathic surgery). Computed tomography (CT) scans were performed in all patients 3 weeks presurgically and 6 months postsurgically. ITKSNAP and 3D Slicer software were used to reconstruct three-dimensional facial skeletal images, to carry out image segmentation, and to superimpose and quantify the TMJ position changes before and after surgery. Amount of displacement of the most medial and lateral points of the condyles and the change of intercondylar angles were measured to evaluate the postsurgical stability of TMJ.

Results: A total amount of 23 skeletal class III patients (female : male = 12 : 11) with age ranged from 20.3 to 33.5 years (mean: 24.39 ± 4.8 years old) underwent Le Fort I maxillary advancement and BSSO setback of the mandible. The surgical outcome revealed the satisfactory correction of their skeletal deformities. The mean displacement of the right most lateral condylar point (RL-RL') was 1.04 ± 0.42 mm and the mean displacement of the left most lateral condylar point (LL-LL') was 1.19 ± 0.41 mm. The mean displacement of the right most medial condylar point (RM-RM') was 1.03 ± 0.39 mm and the left most medial condylar point (LM-LM') was 0.96 ± 0.39 mm. The mean intercondylar angle was 161.61 ± 5.08° presurgically and 159.28 ± 4.92° postsurgically.

Conclusion: The postsurgical position of TM joint condyles in our study only presented a mild change with all the landmark displacement within a range of 1.2 mm. This indicates the bimaxillary orthognathic surgery via 3D CASNOS protocol can achieve a desired and stable result of TMJ position in treating skeletal class III adult patients with retrognathic maxilla and prognathic mandible.

Performances of Whole Tumor Texture Analysis Based on MRI: Predicting Preoperative T Stage of Rectal Carcinomas

Publication: Front Oncol. 2021 Aug 3;11:678441. PMID: 34414105| PDF

Authors: You J, Yin J.

Institution: Department of Radiology, Shengjing Hospital of China Medical University, Shenyang, China.

Abstract: Objective: To determine whether there is a correlation between texture features extracted from high-resolution T2-weighted imaging (HR-T2WI) or apparent diffusion coefficient (ADC) maps and the preoperative T stage (stages T1-2 versus T3-4) in rectal carcinomas.

Materials and methods: One hundred and fifty four patients with rectal carcinomas who underwent preoperative HR-T2WI and diffusion-weighted imaging were enrolled. Patients were divided into training (n = 89) and validation (n = 65) cohorts. 3D Slicer was used to segment the entire volume of interest for whole tumors based on HR-T2WI and ADC maps. The least absolute shrinkage and selection operator (LASSO) was performed to select feature. The significantly difference was tested by the independent sample t-test and Mann-Whitney U test. The support vector machine (SVM) model was used to develop classification models. The correlation between features and T stage was assessed by Spearman's correlation analysis. Multivariate logistic regression analysis was performed to identify independent predictors of tumor invasion. The performance of classifiers was evaluated by the receiver operating characteristic (ROC) curves.

Results: The wavelet HHH NGTDM strength (RS = -0.364, P < 0.001) from HR-T2WI was an independent predictor of stage T3-4 tumors. The shape maximum 2D diameter column (RS = 0.431, P < 0.001), log σ = 5.0 mm 3D first-order maximum (RS = 0.276, P = 0.009), and log σ = 5.0 mm 3D first-order interquartile range (RS = -0.229, P = 0.032) from ADC maps were independent predictors. In training cohorts, the classification models from HR-T2WI, ADC maps and the combination of two achieved the area under the ROC curves (AUCs) of 0.877, 0.902 and 0.941, with the accuracy of 79.78%, 89.86% and 89.89%, respectively. In validation cohorts, the three models achieved AUCs of 0.845, 0.881 and 0.910, with the accuracy of 78.46%, 83.08% and 87.69%, respectively.

Conclusions: Texture analysis based on ADC maps shows more potential than HR-T2WI in identifying preoperative T stage in rectal carcinomas. The combined application of HR-T2WI and ADC maps may help to improve the accuracy of preoperative diagnosis of rectal cancer invasion.

Patient-Specific Coronary Artery Bypass Graft 3D Printing: Implications for Procedural Planning in Complex Percutaneous Coronary Interventions

Publication: J Invasive Cardiol. 2021 Aug;33(8):E592-E603. PMID: 34338650| PDF

Authors: Memon S, Friend E, Samuel SP, Goykhman I, Janzer S, Kalra S, George JC.

Institution: Cardiac Catheterization Laboratory, Einstein Medical Center, 5501 Old York Road, Philadelphia, PA, USA.

Abstract: Background: Three-dimensional (3D) printing technology has seen tremendous growth in augmenting didactics, research, and preprocedural planning with structural heart procedures. Limited investigative efforts have been made in other areas of the cardiovascular spectrum. 3D-printed models (PMs) of anatomically complex coronary artery bypass graft (CABG) patients from coronary computed tomography angiography (CCTA) have implications for adaptive learning and preprocedural planning.

Methods: Five patients with CCTA who underwent subsequent coronary angiography were 3D printed for retrospective comparisons. Standard 3D Slicer software was used to create a computer-aided image of the ascending aorta, native coronary arteries, bypass grafts, aortic arch, and great vessels and 3D printed using polylactic acid filament. The models were painted with acrylic paint to highlight anatomical features and comparison was made with coronary angiography and 3D-CTA images.

Results: All occluded vein grafts, left and right internal mammary artery (IMA) grafts, patent saphenous vein grafts, along with distal graft anastomotic sites, were accurately 3D printed. In cases with chronic total occlusions (CTOs), ambiguous ostial caps, mid or distal vessel chronic occlusions, and occlusions seen as CTOs on coronary angiography were 3D printed showing either distal vessel reconstitution via collaterals or complete arterial filling seen in a setting of calcification, microchannels, and collateral flow. Lastly, 3D printing of the aortic root and great vessels allowed for better appreciation of vessel tortuosity to aid in the cannulation of IMA grafts and optimizing engagement with diagnostic and guiding catheters.

Conclusions: 3D printing of anatomically complex CABG patients has the potential to assist with preprocedural planning and operator understanding of complex coronary anatomy.

Efficacy of Invisalign Attachments: A Retrospective Study

Publication: Am J Orthod Dentofacial Orthop. 2021 Aug;160(2):250-258. PMID: 34217574

Authors: Karras T, Singh M, Karkazis E, Liu D, Nimeri G, Ahuja B.

Institution: Department of Orthodontics, Marquette University School of Dentistry, Milwaukee, WI, USA.

Abstract: Introduction: The purpose of this study was to compare the efficacy of Invisalign's (Align Technology, Santa Clara, Calif) optimized and conventional attachments on rotational and extrusive tooth movements.

Methods: Initial, predicted, and achieved digital dental models from 100 orthodontic patients were exported from Invisalign's ClinCheck software as stereolithography files and subsequently imported into the 3D Slicer CMF program v.4.7.0 for superimpositions on posterior teeth with no planned movement. Rotational and extrusive measurements for both optimized and conventional attachments were made on 382 teeth from the superimposition of the initial and predicted models (predicted movement) and from the superimposed initial and achieved models (achieved movement). Predicted and achieved movements were compared along with movements of teeth with optimized and conventional attachments.

Results: Differences between accuracies of tooth movements using optimized vs conventional attachments for both rotation and extrusion were neither statistically nor clinically significant. Mean predicted values were larger than mean achieved values for all attachment types and movements (P < 0.0001). For extrusion, the mean difference between predicted and achieved movements was clinically significant (0.40 mm and 0.62 mm for optimized and conventional attachments, respectively). Overall, the mean accuracy was 57.2%. Mean accuracy was 63.2% for rotation and 47.6% for extrusion. Interproximal reduction or spacing did not significantly affect accuracy.

Conclusions: Conventional attachment types may be just as effective as Invisalign's proprietary optimized attachments for rotations of canines and premolars and extrusion of incisors and canines. Clinicians should consider overcorrecting tooth movements, especially anterior tooth extrusion.

Association of Regional White Matter Hyperintensity Volumes With Cognitive Dysfunction and Vascular Risk Factors in Patients With Amnestic Mild Cognitive Impairment

Publication: Geriatr Gerontol Int. 2021 Aug;21(8):644-50. PMID: 34105230| PDF

Authors: Hirao K, Yamashita F, Sakurai S, 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: White matter hyperintensities (WMH) obtained by magnetic resonance imaging (MRI) have been reported to promote neurodegeneration and cognitive decline in patients with mild cognitive impairment (MCI). However, little is known about the association between regional WMH (rWMH) and cognitive dysfunction in MCI. We hence investigated the associations between rWMH volumes and cognitive dysfunction in MCI.

Methods: Thirty-eight subjects with amnestic MCI were analysed. The volumes of periventricular hyperintensities (PVH) and deep WMH (DWMH) were measured on a T2-FLAIR MRI using 3D Slicer, and regional PVH and DWMH (rPVH and rDWMH) volumes were calculated. The associations of rPVH and rDWMH volumes with cognition and blood levels of various molecules were investigated. Furthermore, rPVH and rDWMH volumes were compared between MCI with vascular risk factors, such as hypertension, diabetes mellitus (DM), and dyslipidemia, and those without these risk factors.

Results: rPVH volume (bilateral cornu frontale, pars parietalis, and cornu occipitale) positively correlated with Trail Making Test-A/B scores and CysC level, whereas rDWMH volume did not correlate with any of the items. rPVH volumes (right cornu frontale, bilateral pars parietalis and cornu occipitale, and right pars temporalis) and rDWMH volumes (left frontal and parietal lobes) were significantly larger in MCI patients with DM than in those without.

Conclusions: PVH volumes (bilateral areas of cornu frontale, pars parietalis, and cornu occipitale) were closely associated with attention and executive dysfunction. Serum CysC level and DM were associated with WMH volume, suggesting that CysC level and DM might be important markers for determining treatment strategies for white matter abnormalities in MCI.

Development and Validation of a CT-Based Nomogram for Preoperative Prediction of Clear Cell Renal Cell Carcinoma Grades

Publication: Eur Radiol. 2021 Aug;31(8):6078-6086. PMID: 33515086

Authors: Zheng Z, Chen Z, Xie Y, Zhong Q, Xie W.

Institution: Department of Urology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.

Abstract: Objectives: Nuclear grades are proved to be one of the most significant prognostic factors for clear cell renal cell carcinoma (ccRCC). Radiomics nomogram is a widely used noninvasive tool that could predict tumor phenotypes. In this study, we performed radiomics analysis to develop and validate a CT-based nomogram for the preoperative prediction of nuclear grades in ccRCC.

Method: CT images and clinical data of 258 ccRCC patients were retrieved from the Cancer Imaging Archive (TCIA). Radiomics features were extracted from arterial-phase CT images using 3D Slicer software. LASSO regression model was performed to develop a radiomics signature in the training set (n = 143). A radiomics nomogram was constructed combining radiomics signature and selected clinical predictors. Receiver operating characteristic (ROC) curve and calibration curve were used to determine the performance of the radiomics nomogram in the training and validation set (n = 115). Decision curve analysis was used to assess the clinical usefulness of the CT-based nomogram.

Results: One thousand three hundred sixteen radiomics features were extracted from arterial-phase CT images. A radiomics signature, consisting of 20 features, was developed and showed a favorable performance in discriminating nuclear grades with an area under the curve (AUC) of 0.914 and 0.846 in the training and validation set, respectively. The CT-based nomogram, including the radiomics signature and the CT-determined T stage, achieved good calibration and discrimination in the training set (AUC, 0.929; 95% CI, 0.886-0.972) and validation set (AUC, 0.876; 95% CI, 0.812-0.939). Decision curve analysis demonstrated the clinical usefulness of the CT-based nomogram.

Conclusion: The noninvasive CT-based nomogram, including radiomics signature and CT-determined T stage, could improve the accuracy of preoperative grading of ccRCC and provide individualized treatment for ccRCC patients.

Choroidal Macrovessel: Systematic Review and Analysis of Anatomic Origin

Publication: Surv Ophthalmol. 2021 Jul 29:S0039-6257(21)00166-1. 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.

Volumetric Accuracy Analysis of Virtual Safety Barriers for Cooperative-Control Robotic Mastoidectomy

Publication: Otol Neurotol. 2021 Jul 28. PMID: 34325455

Authors: Ding AS, Capostagno S, Razavi CR, Li Z, Taylor RH, Carey JP, Creighton FX.

Institution: Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Abstract: Hypothesis: Virtual fixtures can be enforced in cooperative-control robotic mastoidectomies with submillimeter accuracy.

Background: Otologic procedures are well-suited for robotic assistance due to consistent osseous landmarks. We have previously demonstrated the feasibility of cooperative-control robots (CCRs) for mastoidectomy. CCRs manipulate instruments simultaneously with the surgeon, allowing the surgeon to control instruments with robotic augmentation of motion. CCRs can also enforce virtual fixtures, which are safety barriers that prevent motion into undesired locations. Previous studies have validated the ability of CCRs to allow a novice surgeon to safely complete a cortical mastoidectomy. This study provides objective accuracy data for CCR-imposed safety barriers in cortical mastoidectomies.

Methods: Temporal bone phantoms were registered to a CCR using preoperative computed tomography (CT) imaging. Virtual fixtures were created using 3D Slicer, with 2D planes placed along the external auditory canal, tegmen, and sigmoid, converging on the antrum. Five mastoidectomies were performed by a novice surgeon, moving the drill to the limit of the barriers. Postoperative CT scans were obtained, and Dice coefficients and Hausdorff distances were calculated.

Results: The average modified Hausdorff distance between drilled bone and the preplanned volume was 0.351 ± 0.093 mm. Compared with the preplanned volume of 0.947 cm3, the mean volume of bone removed was 1.045 cm3 (difference of 0.0982 cm3 or 10.36%), with an average Dice coefficient of 0.741 (range, 0.665-0.802).

Conclusions: CCR virtual fixtures can be enforced with a high degree of accuracy. Future studies will focus on improving accuracy and developing 3D fixtures around relevant surgical anatomy.

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. 2021 Jul 9. 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.

Radiomics AI Prediction for Head and Neck Squamous Cell Carcinoma (HNSCC) Prognosis and Recurrence With Target Volume Approach

Publication: BJR Open. 2021 Jul 5;3(1):20200073. PMID: 34381946 | PDF

Authors: Fh T, Cyw C, Eyw C.

Institution: School of Medical and Health Sciences, Tung Wah College, Hong Kong, Hong Kong.

Abstract: Objectives: To evaluate the performance of radiomics features extracted from planning target volume (PTV) and gross tumor volume (GTV) in the prediction of the death prognosis and cancer recurrence rate for head and neck squamous cell carcinoma (HNSCC).

Methods: 188 HNSCC patients' planning CT images with radiotherapy structures sets were acquired from Cancer Imaging Archive (TCIA). The 3D Slicer v.4.10.2 with the PyRadiomics extension (Computational Imaging and Bioinformatics Lab, Harvard medical School) was used to extract radiomics features from the radiotherapy planning images. An in-house developed deep learning artificial neural networks (DL-ANN) model was used to predict death prognosis and cancer recurrence rate based on the features extracted from GTV and PTV of the CT images.

Results: The PTV radiomics features with DL-ANN model could achieve 77.7% accuracy with overall AUC equal to 0.934 and 0.932 when predicting HNSCC-related death prognosis and cancer recurrence respectively. Furthermore, the DL-ANN model can achieve an accuracy of 74.3% with AUC equal to 0.947 and 0.956 for the HNSCC-related death prognosis and cancer recurrence respectively using GTV features.

Conclusion: Using both GTV and PTV radiomics features in the DL-ANN model, can aid in predicting HNSCC-related death prognosis and cancer recurrence. Clinicians may find it helpful in formulating different treatment regimens and facilitate personized medicine based on the predicted outcome when performing GTV and PTV delineation.

Advances in knowledge: Radiomics features of GTV and PTV are reliable prognosis and recurrence predicting tools, which may help clinicians in GTV and PTV delineation to facilitate delivery of personalized treatment.

MRI Radiomic Features-Based Machine Learning Approach to Classify Ischemic Stroke Onset Time

Publication: J Neurol. 2021 Jul 4. 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.

Preliminary Computed Tomography Radiomics Model for Predicting Pretreatment CD8+ T-Cell Infiltration Status for Primary Head and Neck Squamous Cell Carcinoma

Publication: J Comput Assist Tomogr. 2021 Jul-Aug 01;45(4):629-36. PMID: 34519454

Authors: Wang CY, Ginat DT.

Institution: Department of Radiology, The University of Chicago, Chicago, IL, USA.

Abstract: Purpose: Immunotherapy has emerged as a treatment option for head and neck squamous cell carcinoma (HNSCC), with tumor response being linked to the CD8+ T-cell inflammation. The purpose of this study is to assess whether computed tomography (CT) radiomic analysis can predict CD8+ T-cell enrichment in HNSCC primary tumors.

Methods: This retrospective study included 71 patients from a head and neck cancer genomics cohort with CD8+ T-cell enrichment status. Pretreatment contrast-enhanced neck CT scans were retrospectively reviewed using 3D Slicer for primary lesion segmentation.The SlicerRadiomics extension was used to extract 107 radiomic features. Ridge regression and lasso regression were applied for feature selection and model construction.

Results: Lasso regression defined Coarseness as the most important variable, followed by SmallDependenceEmphasis, SmallAreaLowGrayLevelEmphasis, Contrast.1, and Correlation.Ridge regression defined Coarseness as the most important variable, followed by SmallDependenceLowGrayLevelEmphasis, Contrast.1, DependenceNonUniformityNormalized, and Idmn. These variables identified by lasso and ridge regressions were used to create a combined logistic regression model. The area under the curve (AUC) for the lasso-generated model was 0.786 (95% confidence interval [CI], 0.532-1.000), and the AUC for the ridge-generated model was 0.786 (95% CI, 0.544-1.000). Combining the radiomic variables identified by lasso and ridge regressions with clinical characteristics including alcohol use, tobacco use, anatomic site, and initial T stage produced a model with an AUC of 0.898 (95% CI, 0.731-1.000).

Conclusions: T-cell inflammation status of HNSCC primary tumors can be predicted using radiomic analysis of CT imaging and thereby help identify patients who would respond well to immunotherapy.

3D-Printed, Patient-Specific DIEP Flap Templates for Preoperative Planning in Breast Reconstruction: A Prospective Case Series

Publication: Gland Surg. 2021 Jul;10(7):2192-2199. PMID: 34422590 | PDF

Authors: Chae MP, Hunter-Smith DJ, Chung RD, Smith JA, Rozen WM.

Institution: Department of Surgery, School of Clinical Sciences at Monash Health, Monash University, Clayton, Victoria, Australia.

Abstract: Background: Modern imaging technologies, such as computed tomographic angiography (CTA), can be useful for preoperative assessment in deep inferior epigastric artery perforator (DIEP) flap surgery. Planning perforator flap design can lead to improved surgical efficiency. However, current imaging modalities are limited by being displayed on a two-dimensional (2D) surface. In contrast, a 3D-printed model provides tactile feedback that facilitates superior understanding. Hence, we have 3D-printed patient-specific deep inferior epigastric artery perforator (DIEP) templates, in an affordable and convenient manner, for preoperative planning.

Methods: Twenty consecutive patients undergoing 25 immediate or delayed post-mastectomy autologous breast reconstruction with DIEP or muscle-sparing transverse rectus abdominis (MS-TRAM) flaps are recruited prospectively. Using free, open-source softwares (3D Slicer, Autodesk MeshMixer, and Cura) and desktop 3D printers (Ultimaker 3E and Moment), we created a template based on a patient's abdominal wall anatomy from CTA, with holes and lines indicating the position of perforators, their intramuscular course and the DIEA pedicle.

Results: The mean age of patients was 52 [38-67]. There were 15 immediate and 10 delayed reconstructions. 3D printing time took mean 18 hours and 123.7 g of plastic filament, which calculates to a mean material cost of AUD 8.25. DIEP templates accurately identified the perforators and reduced intraoperative perforator identification by 7.29 minutes (P=0.02). However, the intramuscular dissection time was not affected (P=0.34). Surgeons found the template useful for preoperative marking (8.6/10) and planning (7.9/10), but not for intramuscular dissection (5.9/10). There were no immediate flap-related complications.

Conclusions: Our 3D-printed, patient-specific DIEP template is accurate, significantly reduces intraoperative perforator identification time and, hence, may be a useful tool for preoperative planning in autologous breast reconstruction.

An Efficient Method for Aneurysm Volume Quantification Applicable in Any Shape and Modalities

Publication: J Korean Neurosurg Soc. 2021 Jul;64(4):514-23. PMID: 34185985 | PDF

Authors: Chung J, Ko JH.

Institution: Department of Neurosurgery, Dankook University College of Medicine, Cheonan, Korea.

Abstract: Objective: Aneurysm volume quantification (AVQ) using the equation of ellipsoid volume is widely used although it is inaccurate. Furthermore, AVQ with 3-dimensional (3D) rendered data has limitations in general use. A novel universal method for AVQ is introduced for any diagnostic modality and application to any shape of aneurysms.

Methods: Relevant AVQ studies published from January 1997 to June 2019 were identified to determine common methods of AVQ. The basic idea is to eliminate the normal artery volume from 3D model with the aneurysm. After Digital Imaging and Communications in Medicine (DICOM) data is converted and exported to stereolithography (STL) file format, the 3D STL model is modified to remove the aneurysm and the volume difference between the 3D model with/without the aneurysm is defined as the aneurysm volume. Fifty randomly selected aneurysms from DICOM database were used to validate the different AVQ methods.

Results: We reviewed and categorized AVQ methods in 121 studies. Approximately 60% used the ellipsoid method, while 24% used the 3D model. For 50 randomly selected aneurysms, volumes were measured using 3D Slicer, RadiAnt, and ellipsoid method. Using 3D Slicer as the reference, the ratios of mean difference to mean volume obtained by RadiAnt and ellipsoid method were -1.21±7.46% and 4.04±30.54%, respectively. The deviations between RadiAnt and 3D Slicer were small despite of aneurysm shapes, but those of ellipsoid method and 3D Slicer were large.

Conclusion: In spite of inaccuracy, ellipsoid method is still mostly used. We propose a novel universal method for AVQ that is valid, low cost, and easy to use.

Real-Time Tool Detection for Workflow Identification in Open Cranial Vault Remodeling

Publication: Entropy (Basel). 2021 Jun 26;23(7):817. PMID: 34206962 | PDF

Authors: Pose Díez de la Lastra A, García-Duarte Sáenz L, García-Mato D, Hernández-Álvarez L, Ochandiano S, Pascau J.

Institution: Departamento de Bioingeniería e Ingeniería Aeroespacial, Universidad Carlos III de Madrid, Leganés, Spain.

Abstract: Deep learning is a recent technology that has shown excellent capabilities for recognition and identification tasks. This study applies these techniques in open cranial vault remodeling surgeries performed to correct craniosynostosis. The objective was to automatically recognize surgical tools in real-time and estimate the surgical phase based on those predictions. For this purpose, we implemented, trained, and tested three algorithms based on previously proposed Convolutional Neural Network architectures (VGG16, MobileNetV2, and InceptionV3) and one new architecture with fewer parameters (CranioNet). A novel 3D Slicer module was specifically developed to implement these networks and recognize surgical tools in real time via video streaming. The training and test data were acquired during a surgical simulation using a 3D printed patient-based realistic phantom of an infant's head. The results showed that CranioNet presents the lowest accuracy for tool recognition (93.4%), while the highest accuracy is achieved by the MobileNetV2 model (99.6%), followed by VGG16 and InceptionV3 (98.8% and 97.2%, respectively). Regarding phase detection, InceptionV3 and VGG16 obtained the best results (94.5% and 94.4%), whereas MobileNetV2 and CranioNet presented worse values (91.1% and 89.8%). Our results prove the feasibility of applying deep learning architectures for real-time tool detection and phase estimation in craniosynostosis surgeries.

Association Between Tumor Size and Peritumoral Brain Edema in Patients With Convexity and Parasagittal Meningiomas

Publication: PLoS One. 2021 Jun 10;16(6):e0252945. PMID: 34111188 | PDF

Authors: Shin C, Kim JM, Cheong JH, Ryu JI, Won YD, Ko Y, Han MH.

Institution: Department of Neurosurgery, Hanyang University Guri Hospital, Guri, Gyonggi-do, Korea.

Abstract: Background and purpose: Peritumoral brain edema (PTBE) is a common complication in meningioma and disruption of the tumor-brain barrier in meningioma is crucial for PTBE formation. To evaluate the association between meningioma size and PTBE, we measured meningioma volumes using the 3D Slicer in patients with convexity and parasagittal meningiomas.

Methods: Receiver operating characteristic curve analysis was used to determine the optimal cut-off meningioma volume values for predicting PTBE occurrence. Logistic regressions were used to estimate the odds ratios for PTBE occurrence in patients with convexity and parasagittal meningiomas according to several predictive factors.

Results: A total of 205 convexity or parasagittal meningioma patients with no other brain disease who underwent one or more contrast-enhanced brain MRIs were enrolled in this 10-year analysis in two hospitals. The optimal cut-off meningioma volume value for prediction of PTBE in all study patients was 13.953 cc (sensitivity = 76.1%; specificity = 92.5%). If a meningioma is assumed to be a complete sphere, 13.953 cc is about 2.987 cm in diameter.

Conclusions: Our study suggests a cut-off value of 3 cm meningioma diameter for prediction of PTBE in patients with convexity and parasagittal meningiomas. We believe that we have revealed why the meningioma diameter of 3 cm is clinically meaningful.

Volumetric Analysis of Mucous Retention Cysts in the Maxillary Sinus: A Retrospective Study Using Cone-Beam Computed Tomography

Publication: Imaging Sci Dent. 2021 Jun;51(2):117-127. PMID: 34235057 | PDF

Authors: Hung K, Hui L, Yeung AWK, Wu Y, Hsung RT, Bornstein MM.

Institution: Oral and Maxillofacial Radiology, Applied Oral Sciences and Community Dental Care, Faculty of Dentistry, The University of Hong Kong, Hong Kong.

Abstract: cysts (MRCs) in the maxillary sinus and to analyze potential associations of MRCs with dentoalveolar pathologies.

Materials and methods: Cone-beam computed tomography (CBCT) scans exhibiting bilateral maxillary sinuses that were acquired from January 2016 to February 2019 were initially screened. A total of 227 scans (454 sinuses) that fulfilled the inclusion criteria were included. The presence, location, and volumetric characteristics of the diagnosed MRCs were evaluated on CBCT images using the 3D Slicer software platform. The presence of MRCs was correlated with potential influencing factors including age, sex, and dentoalveolar pathology. For MRCs located on the sinus floor, factors with a potential impact on the volume, surface, and diameter were analyzed.

Results: An MRC was present in 130 (28.6%) of the 454 sinuses. Most MRCs were located on the sinus walls and floor. The mean MRC volume, surface, and diameter were 551.21±1368.04 mm3, 228.09±437.56 mm2, and 9.63±5.40 mm, respectively. Significantly more sinuses with associated endodontically treated teeth/periapical lesions were diagnosed with an MRC located on the sinus floor. For MRCs located on the sinus floor, endodontic status exhibited a significant association with increased volume, surface, and diameter.

Conclusion: Periapical lesions might be a contributing factor associated with the presence and volume of MRCs located on the sinus floor. The 3D Slicer software platform was found to be a useful tool for clinicians to analyze the size of MRCs before surgical interventions such as sinus floor elevation procedures.

MONAI Expands its Horizons with Healthcare Imaging Annotation

Publication: nVIDIA DEVELOPER 2021 July 19 |

Authors: Prerna Dogra

Institution: nVIDIA Corporation

Abstract: Open-source frameworks like Project MONAI provide a standardized, transparent, and reproducible template for the creation of, and deployment of medical imaged-focused machine learning models, potentiating efforts such as ours. They allow us to focus on investigating novel algorithms and their application, rather than developing and maintaining software infrastructure.  This in turn has accelerated research progress which we are actively translating into tools of practical relevance to the pediatric community we serve.

  • MONAI v0.1 includes:
    • MONAI Label server: REST API server that facilitates communication with the viewer clients i.e. (3D Slicer, OHIF, etc).
    • MONAI Label sample applications that can be adapted to a given clinical task for MR/CT modality including DeepGrow and DeepEdit which are developed by MONAI researchers.
    • With v0.1, we have released a 3D Slicer plugin for MONAI Label to kick start users in the MONAI Label experience
Build AI-Assisted Annotation Models with MONAI Label | YouTube Video

Transcanal Computed Tomography Views for Transcanal Endoscopic Lateral Skull Base Surgery: Pilot Cadaveric Study.

Publication: J Neurol Surg B Skull Base. 2021 Jun;82(3):338-44. PMID: 34026410

Authors: Lubner RJ, Barber SR, Knoll RM, Kempfle J, Lee DJ, Reinshagen KL, Remenschneider AK, Kozin ED.

Institution: Department of Otolaryngology, Massachusetts Eye and Ear, Boston, MA, USA.

Abstract: Cadaveric temporal bones ( n = 6) from three specimens underwent high-resolution CT (0.625 mm slice thickness). Using three-dimensional (3D Slicer v.4.8, reformatted "transcanal" views in the plane of the external auditory canal (EAC) were created. Axial and coronal reformats were used to compare and measure distances between anatomic structures in the plane of the EAC.

Fusion of Subarachnoid Hemorrhage Data and Computed Tomography Angiography Data Is Helpful to Identify the Rupture Source in Patients With Multiple Intracranial Aneurysms

Publication: Neurosurg Rev. 2021 Jun;44(3):1411-6. PMID: 32506389

Authors: Yao A, Jia L, Li J, Wang B, Zhang J, Xue Z, Zhao K, Zhao Y, You N, Zhang J, Xu B.

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

Abstract: Determining the rupture source is imperative in patient with aneurysmal subarachnoid hemorrhage (SAH). About one third of SAH cases with multiple intracranial aneurysms cannot be certain of the rupture source according to the hemorrhage pattern. This study aims to identify of the rupture source in patients with multiple intracranial aneurysms by fusing SAH data and computed tomography angiography (CTA) data. This retrospective study included 52 aneurysmal SAH patients with multiple intracranial aneurysms. In the 52 patients, 36 had definitive hemorrhage patterns on computed tomography imaging. And the other 16 patients had non-definitive hemorrhage patterns, which were bewildered for us to determine the ruptured aneurysms. Fusion of SAH data and CTA data was performed to demonstrate the spatial relationship between the SAH with each aneurysm by using the 3D Slicer software. For the patients with definitive bleed patterns, all of the suspected ruptured aneurysms were confirmed to be accurate according to the surgical records. Interestingly, the suspected rupture sources were correct in 14 of 16 patients with non-definitive hemorrhage patterns. For all 52 patients with multiple intracranial aneurysms, the ruptured aneurysms were identified in 50 cases (96.2%). In conclusion, fusion of SAH data and CTA data can precisely demonstrate the spatial relationship between the SAH with each aneurysm, which is helpful to determine the ruptured aneurysm in patients with multiple intracranial aneurysms.

Assessment of Pulp Volume Changes After Surgically Assisted Rapid Palatal Expansion

Publication: J Stomatol Oral Maxillofac Surg. 2021 Jun;122(3):263-6. PMID: 32621998

Authors: Guler AY, Isik BK, Esen A, Menziletoglu D.

Institution: Oral and Maxillofacial Surgery Department, Soke Oral and Dental Health Centre, Aydin, Turkey.

Abstract: Maxillary transverse deficiency is a common skeletal problem. When the patient is younger, it is treated by rapid palatal expansion by using orthodontic appliances. If this fails or the patient is older, which means skeletal growth is completed, surgically aided rapid palatal expansion (SARPE) becomes necessary. In this technique, after the osteotomies have been made, the two maxillary bones are distracted by tooth-borne device. Since a tooth-borne device will apply the distraction forces on the teeth, the pulp volumes may change. Our aim was to investigate the volume changes of the tooth pulps after SARPE in which a tooth-borne device was used. We scanned our database and included 20 patients (7 males and 13 females) aging between 16 and 30 (mean 19.5±3.97) to this retrospective study. All the patients had undergone SARPE surgeries and they had pre-surgery and postconsolidation cone beam computerized tomography (CBCT) images. All the surgeries had been done in similar ways; all the patients had used similar tooth-borne modified acrylic bonded expansion device. We divided the maxillary teeth into three groups: the incisors, the premolars and the molars. We imported the CBCT images of each patient into 3D Slicer software. We calculated volumes of pulps for all maxillary teeth. We compared volumes with paired t test. Statistical significance level was accepted as P< .05. The devices had been left in place between 83 and 179 days including distraction and consolidation periods (mean 121.35±27.83 days). Amount of the expansions varied between 6.03mm and 11.16mm (mean 7.19±1.18mm). We found a statistically significant decrease of the pulp volumes in incisor, premolar and molar teeth (P<.001) between pre-surgery and postconsolidation periods. When using tooth-borne devices in SARPE, their impacts on teeth pulps should also be considered.

A New Method to Determine the Optimal Orientation of Slim Modiolar Cochlear Implant Electrode Array Insertion

Publication: Ideggyogy Sz. 2021 May 30;74(5-6):191-5. PMID: 34106549

Authors: Horváth B, Perényi Á, Molnár AF, Csanády M, Kiss GJ, Rovó L.

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

Abstract: Our goal was to determine the optimal orientation of insertion of the Slim Modiolar electrode and develop an easy-to-use method to aid implantation surgery. In some instances, the electrode arrays cannot be inserted in their full length. This can lead to buckling, interscalar dislocation or tip fold-over. In our opinion, one of the possible reasons of tip fold-over is unfavourable orientation of the electrode array. Our goal was to determine the optimal orientation of the Slim Modiolar electrode array relative to clear surgical landmarks and present our method in one specified case.

For the measurement, we used the preoperative CT scan of one of our cochlear implant patients. These images were processed by an open source and free image visualization software: 3D Slicer.

Impact of the Craniofacial Surgery Simulation in Anterior Plagiocephaly on Orbits and Oculomotor Muscles: Biomechanical Analysis With a Finite Element Model

Publication: J Craniofac Surg. 2021 May 28. PMID: 34054084

Authors: Dalmas F, Thollon L, Beylerian M, Godio Raboutet Y, David T, Scavarda D, Denis D, Pech-Gourg G.

Institution: Department of Ophthalmology, University Medical Center, Marseille, France.

Abstract: The aim of this study was to show the displacements and strain induced by the supraorbital band advancement during a craniofacial surgery for an anterior plagiocephaly on the orbital bones and the orbital content thanks to a numerical surgical simulation using the finite element method. A three-dimensional (3D) finite element model of a child with an anterior plagiocephaly was entirely created from a tomodensitometry of a patient followed by our Craniofacial Pediatric team. Data of the tomodensitometry were computed with 3D Slicer to re-create the orbit geometry.

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

Publication: Int J Gynaecol Obstet. 2021 May 17. 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: 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. Digital Imaging and Communications in Medicine files containing MR images with varying severity of PAS (n = 4) were modeled using 3D Slicer.

Structural Failure Sites in Posterior Vaginal Wall Prolapse: Stress 3D MRI-Based Analysis

Publication: Int Urogynecol J. 2021 Jun;32(6):1399-1407. PMID: 33704534

Authors: Chen L, Xie B, Fenner DE, Duarte Thibault ME, Ashton-Miller JA, DeLancey JO.

Institution: Department of Obstetrics and Gynecology, University of Michigan, Ann Arbor, MI, USA.

Abstract: We studied three-dimensional stress MRI at maximal Valsalva of 25 women with (cases) and 25 without (controls) posterior vaginal prolapse of similar age and parity. Vaginal wall factors (posterior wall length and width); attachment factors (paravaginal posterior wall location, posterior fornix height, and perineal height); and hiatal factors (hiatal size and levator ani defects) were measured using 3D Slicer 4.3.0® and a custom Python program. Stepwise linear regression was used to assess the relative contribution of all factors to the posterior prolapse size.

Long-Term Stability and Condylar Remodeling After Mandibular Advancement: A 5-Year Follow-Up

Publication: Am J Orthod Dentofacial Orthop. 2021 May;159(5):613-26. PMID: 33712310 | PDF

Authors: Ehardt L, Ruellas A, Edwards S, Benavides E, Ames M, Cevidanes L.

Institution: Department of Orthodontics and Pediatric Dentistry, School of Dentistry, University of Michigan, Ann Arbor, MI, USA.

Abstract: Forty-two patients underwent bilateral sagittal split osteotomies for mandibular advancement using rigid fixation. Cone-beam computed tomography (CBCT) scans were acquired before surgery (T1), immediately after surgery (T2), and at long-term follow-up (T3). The average follow-up period was 5.3 ± 1.7 years after surgery. Anatomic landmark identification on the cone-beam computed tomographies and subsequent quantification of the changes from T1 to T2 and T2 to T3 were performed in ITK-SNAP (version 2.4; itksnap.org) and 3D Slicer v.4.7 software.

The Development of Novel 2-in-1 Patient-Specific, 3D-Printed Laminectomy Guides with Integrated Pedicle Screw Drill Guides

Publication: World Neurosurg. 2021 May;149:e821-e827. PMID: 33540103

Authors: Kanawati A, Rodrigues Fernandes RJ, Gee A, Urquhart J, Siddiqi F, Gurr K, Bailey CS, Rasoulinejad P.

Institution: London Health Science Centre, Victoria Hospital-London, Ontario, Canada.

Abstract: This was a cadaveric study designed to test novel 2-in-1 patient-specific laminectomy guides, with modular removable pedicle screw drill guides. Three-dimensional (3D) printing has not been applied to laminectomy. This cadaveric study tests novel 2-in-1 patient-specific laminectomy guides, with modular removable pedicle screw drill guides. Computed tomography (CT) scans of 3 lumbar spines were imported into 3D Slicer. Spinal models and patient-specific guides were created and 3D printed. The bones were cleaned to visualize and record the under surface of the lamina during laminectomy. Pedicle screws and laminectomies were performed with the aid of patient-specific guides. CT scans were performed to compare planned and actual screw and laminectomy positions.

Creating a Cross-Sectional, CT and MR Atlas of the Pannon Minipig.

Publication: Anat Histol Embryol. 2021 May;50(3):562-71. PMID: 33529429

Authors: Petnehazy O, Donko T, Ellis R, Csoka A, Czeibert K, Baksa G, Zucker E, Repa K, Takacs A, Repa I, Moizs M.

Institution: Medicopus Nonprofit Ltd, Kaposvar, Hungary.

Abstract: The purpose of this study was to create a detailed cross-sectional anatomical reference atlas of the Pannon minipig by correlating good resolution CT and MR images with high quality cross-sectional anatomical images. According to the authors knowledge, no detailed anatomical atlas is available for the minipig.

"...the CT and MR scans were imported to 3D Slicer."

Optimization of Manufacturing Parameters and Tensile Specimen Geometry for Fused Deposition Modeling (FDM) 3D-Printed PETG

Publication: Materials (Basel). 2021 May 14;14(10):2556. PMID: 34069230 | PDF

Authors: Özen A, Auhl D, Völlmecke C, Kiendl J, Abali BE.

Institution: Institute of Material Science and Technology, Technische Universität Berlin, Germany.

Abstract: Additive manufacturing provides high design flexibility, but its use is restricted by limited mechanical properties compared to conventional production methods. As technology is still emerging, several approaches exist in the literature for quantifying and improving mechanical properties. In this study, we investigate characterizing materials' response of additive manufactured structures, specifically by fused deposition modeling (FDM). A comparative analysis is achieved for four different tensile test specimens for polymers based on ASTM D3039 and ISO 527-2 standards. Comparison of specimen geometries is studied with the aid of computations based on the Finite Element Method (FEM). Uniaxial tensile tests are carried out, after a careful examination of different slicing approaches for 3D printing. We emphasize the effects of the chosen slicer parameters on the position of failures in the specimens and propose a simple formalism for measuring effective mechanical properties of 3D-printed structures.


"...this CAD model is converted by software, called a 3D Slicer, to a 3D printing code, where process information is supplied for manufacturing."

The Use of Cochlear-Enhancement Imaging to Predict Hearing Preservation Following Vestibular Schwannoma Removal

Publication: J Neurosurg Sci. 2021 May 3. PMID: 33940784

Authors: Kim WH, Park HH, Ahn SJ, Park M, Hong CK.

Institution: Department of Neurosurgery, Brain Tumor Center, Gangnam Severance Hospital, Yonsei University Health System, Seoul, Republic of Korea.

Abstract: Background: Hearing preservation is challenging for patients after the removal of large vestibular schwannomas (VSs). Here, using preoperative magnetic resonance (MR) imaging, we investigated the significance of cochlear enhancement (CE) for predicting postoperative hearing preservation.

Methods: Between January 2014 and December 2019, 34 VS-patients with serviceable hearing underwent tumor-removal surgery using a retrosigmoid approach. The presence or absence of CE using both T2-weighted and gadolinium-enhanced T1-weighted MR images was assessed in VS patients using the pixel-analysis method. Segmented volumetric analyses were also performed using GrowCut 3D Slicer software.

Manual Versus Semiautomatic Segmentation of Soft-Tissue Sarcomas on Magnetic Resonance Imaging: Evaluation of Similarity and Comparison of Segmentation Times

Publication: Radiol Bras. May-Jun 2021;54(3):155-64. PMID: 34108762 | PDF

Authors: Dionisio FCF, Oliveira LS, Hernandes MA, Engel EE, de Azevedo-Marques PM, Nogueira-Barbosa MH.

Institution: Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo, SP, Brazil.

Abstract: Objective: To evaluate the degree of similarity between manual and semiautomatic segmentation of soft-tissue sarcomas on magnetic resonance imaging (MRI).

Materials and methods: This was a retrospective study of 15 MRI examinations of patients with histopathologically confirmed soft-tissue sarcomas acquired before therapeutic intervention. Manual and semiautomatic segmentations were performed by three radiologists, working independently, using the software 3D Slicer. The Dice similarity coefficient (DSC) and the Hausdorff distance were calculated in order to evaluate the similarity between manual and semiautomatic segmentation. To compare the two modalities in terms of the tumor volumes obtained, we also calculated descriptive statistics and intraclass correlation coefficients (ICCs).

Comparing the Inter-Observer Reliability of the Tada Formula Among Neurosurgeons While Estimating the Intracerebral Haematoma Volume

Publication: Clin Neurol Neurosurg. 2021 May 1;205:106668. PMID: 33962148

Authors: Gong K, Shi T, Zhao L, Xu Z, Wang Z.

Institution: Department of Neurosurgery, The First Affiliated Hospital of Xia'men University, Xia'men, Fujian, China.

Abstract: Objective: To compare the inter-observer reliability among neurosurgeons while estimating the intracerebral haematoma (ICH) volume by the Tada formula and assess its influence on predicting the severity and prognosis of various ICHs.

Methods: We obtained clinical data from 262 consecutive patients with spontaneous ICH. The haematoma volume was independently calculated and compared by 3D Slicer and eight neurosurgeons. The inter-observer reliability was obtained by calculating the intraclass correlation coefficients (ICC) and Cohen's kappa score (kappa), within different shape and volume ICH subgroups.

Post-Discharge Chest CT Findings and Pulmonary Function Tests in Severe COVID-19 Patients

Publication: Eur J Radiol. 2021 May;138:109676. PMID: 33798931 | PDF

Authors: Balbi M, Conti C, Imeri G, Caroli A, Surace A, Corsi A, Mercanzin E, Arrigoni A, Villa G, Di Marco F, Bonaffini PA, Sironi S.

Institution: Department of Radiology, ASST Papa Giovanni XXIII, Bergamo, Italy.

Abstract: COVID-19 patients admitted to our hospital between February 25 and May 2, 2020, were retrospectively included according to the following criteria: (a) COVID-19 defined as severe based on the WHO interim guidance (i.e., clinical signs of pneumonia plus respiratory rate > 30 breaths/min, severe respiratory distress, and/or SpO2 < 90 % on room air); (b) chest radiograph in the acute setting; (c) post-discharge unenhanced chest CT; and (d) post-discharge comprehensive PFT. Imaging findings were retrospectively evaluated in consensus by two readers, and volume of abnormal lung was measured on CT using 3D Slicer software. Differences between demographics, comorbidities, acute radiographic findings, PFT, and post-discharge clinical and laboratory data of patients with normal and abnormal CT findings were assessed by Mann-Whitney or Fisher tests, and the compromised lung volume-PFT association by Pearson correlation after removing possible outliers.

Radiomic Analysis of the Optic Nerve at the First Episode of Acute Optic Neuritis: An Indicator of Optic Nerve Pathology and a Predictor of Visual Recovery?

Publication: Radiol Med. 2021 May;126(5):698-706. PMID: 33392980

Authors: Cellina M, Pirovano M, Ciocca M, Gibelli D, Floridi C, Oliva G.

Institution: Radiology Department, ASST Fatebenefratelli Sacco, Piazza Principessa Clotilde 3, 20123, Milan, Italy.

Abstract: We reviewed imaging and clinical data of 25 patients with a first episode of optic neuritis (ON) (14 females, 11 males; 5 bilateral ON; 7 left ON; 13 right ON). All patients underwent a complete ophthalmological assessment, including visual acuity and RNFL, neurological evaluation, orbits MRI. Segmentation of the optic nerves was performed through 3D Slicer open software to get radiomics analysis. All patients underwent a complete neuro-ophthalmological follow-up at 6 months to assess the VO, classified as: complete recovery, partial recovery, deficit persistence/relapse, or visual worsening and were diagnosed as MS or clinically isolated syndrome.

Radiomic Machine Learning Classifiers in Spine Bone Tumors: A Multi-Software, Multi-Scanner Study

Publication: Eur J Radiol. 2021 Apr;137:109586. PMID: 33610852

Authors: Chianca V, Cuocolo R, Gitto S, Albano D, Merli I, Badalyan J, Cortese MC, Messina C, Luzzati A, Parafioriti A, Galbusera F, Brunetti A, Sconfienza LM.

Institution: Clinica di Radiologia EOC, Istituto di Imaging della Svizzera Italiana (IIMSI), Lugano, Switzerland.

Abstract: Purpose: Spinal lesion differential diagnosis remains challenging even in MRI. Radiomics and machine learning (ML) have proven useful even in absence of a standardized data mining pipeline. We aimed to assess ML diagnostic performance in spinal lesion differential diagnosis, employing radiomic data extracted by different software.

Methods: Patients undergoing MRI for a vertebral lesion were retrospectively analyzed (n = 146, 67 males, 79 females; mean age 63 ± 16 years, range 8-89 years) and constituted the train (n = 100) and internal test cohorts (n = 46). Part of the latter had additional prior exams which constituted a multi-scanner, external test cohort (n = 35). Lesions were labeled as benign or malignant (2-label classification), and benign, primary malignant or metastases (3-label classification) for classification analyses. Features extracted via 3D Slicer heterogeneityCAD module (hCAD) and PyRadiomics were independently used to compare different combinations of feature selection methods and ML classifiers (n = 19).

Wearable Mixed-Reality Holographic Navigation Guiding the Management of Penetrating Intracranial Injury Caused by a Nail

Publication: J Digit Imaging. 2021 Apr 12. PMID: 33846887

Authors: Li Y, Huang J, Huang T, Tang J, Zhang W, Xu W, Wang N, Deng Y, Yu X, Xu L.

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

Abstract: Penetrating brain injury caused by a nail is an extremely rare neurosurgical emergency that poses a challenge for neurosurgeons. Nail entering the brain from the orbit and lodging within the cranial cavity is even more unusual. A 53-year-old male was found unconscious at a construction site, and brain CT revealed not only the presence of a nail beneath the inner table of the parietal bone, but also traumatic intracerebral hematoma. Consequently, accurate localization of the nail and hematoma was mandatory for surgical plan. During surgical planning, computational model reconstruction and trajectory calculation were completed using preoperative CT in 3D Slicer.

BreastImplantAnalyzer: An Easy-to-Use, Validated Tool for Calculating Breast Implant Volume From MRI Data

Publication: J Plast Reconstr Aesthet Surg. 2021 Apr 8;S1748-6815(21)00158-3. PMID: 33972201

Authors: Levine L, Kassira W.

Institution: University of Miami Miller School of Medicine, Miami, USA.

Abstract: Given the prevalence of breast augmentation and prosthetic-based breast reconstruction, it is common for the plastic surgeon to see patients presenting for revisional implant surgery. A frequent issue encountered in such procedures is uncertainty of implant size, which presents numerous challenges and may lead to undesired outcomes for both the patient and the surgeon. There is currently no tool available with the purpose of measuring implant volume from magnetic resonance imaging (MRI) data. In this study, such a program was designed and tested.

"...plastic surgeons can easily calculate breast implant volume pre-operatively using BreastImplantAnalyzer, which is available to download for free from www.BreastImplantAnalyzer.com or as an extension for the popular medical imaging platform 3D Slicer.

Application of 3D Modeling and Fusion Technology of Medical Image Data in Image Teaching

Publication: BMC Med Educ. 2021 Apr 6;21(1):194. PMID: 33823845 | PDF

Authors: Yuan Q, Chen X, Zhai J, Chen Y, Liu Q, Tan Z, Chen G, Zhuang K, Zhang J, Xu X, Qiang D, Shao X.

Institution: Department of Imaging, Yi-Ji Shan Hospital, Wannan Medical College, Anhui, China.

Abstract: A total of 460 medical imaging students were selected and randomly divided into two groups. The research group received the teaching of the fusion of the original CT and MR data 3D model and the original image combined with 3D anatomical image. CT and MRI data are imported through load DICOM of 3D Slicer.

Radiomics Analysis for Predicting Pembrolizumab Response in Patients With Advanced Rare Cancers

Publication: J Immunother Cancer. 2021 Apr;9(4):e001752. PMID: 33849924 | PDF

Authors: Colen RR, Rolfo C, Ak M, Ayoub M, Ahmed S, Elshafeey N, Mamindla P, Zinn PO, Ng C, Vikram R, Bakas S, Peterson CB, Rodon Ahnert J, Subbiah V, Karp DD, Stephen B, Hajjar J, Naing A.

Institution: Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA.

Abstract: The study included 57 patients with advanced rare cancers who were enrolled in our phase II clinical trial of pembrolizumab. Tumor response was evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and immune-related RECIST (irRECIST). Patients were categorized as 20 "controlled disease" (stable disease, partial response, or complete response) or 37 progressive disease). We used 3D Slicer to segment target lesions on standard-of-care, pretreatment contrast enhanced CT scans. We extracted 610 features (10 histogram-based features and 600 second-order texture features) from each volume of interest. Least absolute shrinkage and selection operator logistic regression was used to detect the most discriminatory features. Selected features were used to create a classification model, using XGBoost, for the prediction of tumor response to pembrolizumab. Leave-one-out cross-validation was performed to assess model performance.

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

Publication: J Orofac Orthop. 2021 Mar 30. 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.

3D Printing of Rapid, Low-Cost and Patient-Specific Models of Brain Vasculature for Use in Preoperative Planning in Clipping of Intracranial Aneurysms

Publication: J Clin Med. 2021 Mar 13;10(6):1201. PMID: 33805774 | PDF

Authors: Błaszczyk M, Jabbar R, Szmyd B, Radek M.

Institution: Department of Neurosurgery, Spine and Peripheral Nerves Surgery, Medical University of Łódź, Łódź, Poland.

Abstract: We developed a practical and cost-effective method of production of a 3D-printed model of the arterial Circle of Willis of patients treated because of an intracranial aneurysm. We present and explain the steps necessary to produce a 3D model from medical image data, and express the significant value such models have in patient-specific pre-operative planning as well as education. A Digital Imaging and Communications in Medicine (DICOM) viewer is used to create 3D visualization from a patient's Computed Tomography Angiography (CTA) images. After generating the reconstruction, we manually remove the anatomical components that we wish to exclude from the print by utilizing tools provided with the imaging software. We then export this 3D reconstructions file into a Standard Triangulation Language (STL) file which is then run through a 3D Slicer software to generate a G-code file for the printer.


Early Prediction of Putamen Imaging Features in HIV-Associated Neurocognitive Impairment Syndrome

Publication: BMC Neurol. 2021 Mar 9;21(1):106. PMID: 33750319 | PDF

Authors: Qi Y, Xu M, Wang W, Wang YY, Liu JJ, Ren HX, Liu MM, Li RL, Li HJ.

Institution: Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China.

Abstract: Retrospective selection of 90 patients with HIV infection, including 36 asymptomatic neurocognitive impairment (ANI) patients and 54 pre-clinical ANI patients in Beijing YouAn Hospital. All patients received comprehensive neuropsychological assessment and MRI scanning. 3D Slicer software was used to acquire volume of interest (VOI) and radiomics features.

Use of Volumetric CT Scanning to Predict Tumor Staging and Survival in Pancreatic Cancer Patients That Are to Be Administered Curative Resection

Publication: J Surg Oncol. 2021 May;123(8):1757-63. PMID: 33684252

Authors: Sengul Samanci N, Çelik E, Bagcilar O, Tutar O, Samanci C, Velidedeoglu M, Yassa AE, Demirci NS, Demirelli FH.

Institution: Department of Medical Oncology, Cerrahpasa Medical Faculty, Istanbul University-Cerrahpasa, Istanbul, Turkey.

Abstract: Methods: Tumor volume was measured from contrast enhanced CT images of 58 patients who undergo curative resection for pancreatic cancer using the Segment Editor module implemented in 3D Slicer, a free open source software platform. Receiver operating characteristic (ROC) analysis was used to evaluate correlation between Tvol and pTNM staging.

Fitting Unbranching Skeletal Structures to Objects

Publication: Med Image Anal. 2021 May;70:102020. PMID: 33743355

Authors: Liu Z, Hong J, Vicory J, Damon JN, Pizer SM.

Institution: Department of Computer Science, University of North Carolina at Chapel Hill, USA.

Abstract: Representing an object by a skeletal structure can be powerful for statistical shape analysis if there is good correspondence of the representations within a population. Many anatomic objects have a genus-zero boundary and can be represented by a smooth unbranching skeletal structure that can be discretely approximated. We describe how to compute such a discrete skeletal structure ("d-s-rep") for an individual 3D shape with the desired correspondence across cases. The method involves fitting a d-s-rep to an input representation of an object's boundary. A good fit is taken to be one whose skeletally implied boundary well approximates the target surface in terms of low order geometric boundary properties: (1) positions, (2) tangent fields, (3) various curvatures. Our method involves a two-stage framework that first, roughly yet consistently fits a skeletal structure to each object and second, refines the skeletal structure such that the shape of the implied boundary well approximates that of the object. The first stage uses a stratified diffeomorphism to produce topologically non-self-overlapping, smooth and unbranching skeletal structures for each object of a population. The second stage uses loss terms that measure geometric disagreement between the skeletally implied boundary and the target boundary and avoid self-overlaps in the boundary. By minimizing the total loss, we end up with a good d-s-rep for each individual shape. We demonstrate such d-s-reps for various human brain structures. The framework is accessible and extensible by clinical users, researchers and developers as an extension of SlicerSALT, which is based on 3D Slicer.

Three-Dimensional Modeling and Automatic Analysis of the Human Nasal Cavity and Paranasal Sinuses Using the Computational Fluid Dynamics Method

Publication: Eur Arch Otorhinolaryngol. 2021 May;278(5):1443-53. PMID: 33068172 | PDF

Authors: Tretiakow D, Tesch K, Meyer-Szary J, Markiet K, Skorek A.

Institution: Department of Otolaryngology, Gdansk Medical University, Gdansk, Poland.

Abstract: This study is based on CT images of 16 patients. Image processing and model generation of the human nasal cavity and paranasal sinuses were performed using open-source and freeware software. 3D Slicer was used primarily for segmentation and new surface model generation. Further processing was done using Autodesk® Meshmixer TM. The governing equations are discretized by means of the finite volume method. Subsequently, the corresponding algebraic equation systems were solved by OpenFOAM software.

Comparison Between Computed Tomography and Silicone-Casting Methods to Determine Gunshot Cavities in Ballistic Soap

Publication: Int J Legal Med. 2021 May;135(3):829-36. PMID: 33190163

Authors: Burgos-Díez I, Zapata F, Chamorro-Sancho MJ, Ruano-Rando MJ, Ferrando-Gil JL, García-Ruiz C, Montalvo G, Ortega-Ojeda F.

Institution: Ballistics and Tool marks Department, Criminalistics Service, Guardia Civil HQ, Madrid, Spain.

Abstract: Current methods used in terminal ballistics to determine the volume of temporary cavities created by projectiles in soft tissue simulants (such as ballistic soap) usually involve silicone-casting to obtain the cavity moulds. However, these methods have important drawbacks including their little sensitivity and precision, besides the fact that they are destructive. Imaging techniques such as computed tomography (CT) might not only overcome those limitations but also offer useful tools for digitally reporting the scientific results. This work accomplished the 3D digital reconstruction of the cavities created by different projectiles in ballistic soap blocks. This way, the total volume of the cavities, the projectile penetration depths, and other measurements were determined, rendering better capabilities when compared to the current silicone method. All these features were achieved through the CT analysis and 3D Slicer imaging software. In addition, it is worth mentioning that the method can preserve the evidence by digitally obtaining, signing, and storing the infographic videos displaying the 3D-reconstructed cavities. Graphical abstract.

A Machine Learning-Based Radiomics Model for the Prediction of Axillary Lymph-Node Metastasis in Breast Cancer

Publication: Breast Cancer. 2021 May;28(3):664-71. PMID: 33454875

Authors: Song BI.

Institution: Department of Nuclear Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu, Republic of Korea.

Abstract: A total of 100 consecutive IDC patients who underwent surgical resection of primary tumor with sentinel lymph-node biopsy and/or ALN dissection without any neoadjuvant treatment were analyzed. Volume of interests (VOIs) were drawn more than 2.5 of standardized uptake value in the primary tumor on the PET scan using 3D Slicer. Pyradiomics package was used for the extraction of texture features in python. The radiomics prediction model for ALN metastasis was developed in 75 patients of the training cohort and validated in 25 patients of the test cohort. XGBoost algorithm was utilized to select features and build radiomics model. The sensitivity, specificity, and accuracy of the predictive model were calculated.

Cost-Effective Fetal Lung Volumetry for Assessment of Congenital Diaphragmatic Hernia

Publication: Eur J Obstet Gynecol Reprod Biol. 2021 May;260:22-8. PMID: 33713885

Authors: Corroenne R, Zhu KH, Johnson R, Mehollin-Ray AR, Shamshirsaz AA, Nassr AA, Belfort MA, Cortes MS, Shetty A, Lee W, Espinoza J.

Institution: Department of Obstetrics and Gynecology, Texas Children's Hospital & Baylor College of Medicine, Houston, TX, USA.

Abstract: Objectives: (1) To investigate the reproducibility of total fetal lung volume (TFLV) measurements using a free 3D modeling software, 3D Slicer; (2) To correlate these measurements with lung-to-head ratio (LHR) or TFLV measured using PACS and; (3) To determine the role of 3DSlicer in predicting perinatal outcomes in cases with congenital diaphragmatic hernia (CDH) who had fetal tracheal occlusion (FETO).

The Role of Recipient Myosteatosis in Graft and Patient Survival After Deceased Donor Liver Transplantation

Publication: J Cachexia Sarcopenia Muscle. 2021 Apr;12(2):358-67. PMID: 33525056 | PDF

Authors: Czigany Z, Kramp W, Lurje I, Miller H, Bednarsch J, Lang SA, Ulmer TF, Bruners P, Strnad P, Trautwein C, von Websky MW, Tacke F, Neumann UP, Lurje G.

Institution: Department of Surgery and Transplantation, University Hospital RWTH Aachen, Aachen, Germany. 

Abstract: Clinical data from 225 consecutive OLT recipients from a prospective database were retrospectively analysed (May 2010 to December 2017). Computed tomography‐based lumbar skeletal muscle index (SMI) (muscle mass) and mean skeletal muscle radiation attenuation (SM‐RA) (myosteatosis) were calculated using a segmentation tool, 3D Slicer. Patients with low skeletal muscle mass (low SMI) and myosteatosis (low SM‐RA) were identified using predefined and validated cut‐off values.

3D-Assisted Mandibular Reconstruction: A Technical Note of Fibula Free Flap With Preshaped Titanium Plate

Publication: Ann Chir Plast Esthet. 2021 Apr;66(2):174-9. PMID: 32753249

Authors: Villa S, Druelle C, Juliéron M, Nicot R.

Institution: Service de chirurgie maxillo-faciale et stomatologie, university de Lille, Lille cedex, France.

Abstract: The purpose of this technical note is to illustrate a simple and economical preoperative method for preshaping a reconstructive titanium plate in a fibula free flap (FFF) by using 3D printing of a virtually reconstructed mandible haptic model. The whole process consisted in creating a 3D model of the patient's mandible based on a CT-scan using a combination of free software (3D Slicer and ITK-snap), and simulating the surgical osteotomies and reconstruction, and print it as a guide for bending a reconstruction titanium plate. Reconstruction is performed using virtual cubes (1 to 3 cubes, according the number of FFF osteotomies). This virtual lab work is performed using 3D Builder® (Microsoft, Redmond) software. This technique allows obtaining an optimal plate application on the bony fragments. It facilitates reconstructive surgery with good functional (putting the patient back in an optimal dental occlusion based on the native maxilla) and aesthetic results. This technical note presents a simple and economical preoperative fabrication of a reconstructive plate through freeware and a low-cost 3D printer accessible to all surgeons.

Radiomics Approaches for Predicting Liver Fibrosis With Nonenhanced T1 -Weighted Imaging: Comparison of Different Radiomics Models

Publication: J Magn Reson Imaging. 2021 Apr;53(4):1080-9. PMID: 33043991

Authors: Ni M, Wang L, Yu H, Wen X, Yang Y, Liu G, Hu Y, Li Z.

Institution: Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, China.

Abstract: Liver fibrosis rats were induced via subcutaneous injection of a mixture of carbon tetrachloride. Rats in the control group were injected with saline. Segmentation and feature extraction were performed by 3D Slicer and the image biomarker explorer (IBEX) software package. Data preprocessing, feature selection, model building, and model comparative evaluation were conducted with Python. The liver fibrosis stage was determined by pathological examination.

Clinical 3D Imaging of the Anterior Segment With Ultrasound Biomicroscopy

Publication: Transl Vis Sci Technol. 2021 Mar 1;10(3):11. PMID: 34003945 | PDF

Authors: Helms RW, Minhaz AT, Wilson DL, Örge FH.

Institution: Center for Pediatric Ophthalmology and Adult Strabismus, Rainbow Babies and Children's Hospital, University Hospitals Cleveland Medical Center, Cleveland, OH, USA.

Abstract: Ultrasound biomicroscopy (UBM) is an important ophthalmic imaging modality due to its ability to see behind pigmented iris and to visualize anterior chamber when the eye's transparency is compromised. We created a three-dimensional UBM (3D-UBM) system and acquired example images to illustrate its potential.

In vivo imaging of rabbit anterior chamber. Rabbits were sedated, and the probe was attached to a flexible arm and positioned over the rabbit's eye. The AC was scanned using 100 frames. The AC was manually segmented (3D Slicer software) to determine AC volume and depth. This figure shows the segmented AC (green) with part of the cornea cropped away.

Prognosis Predicting Value of Semiquantitative Parameters of Visceral Adipose Tissue and Subcutaneous Adipose Tissue of 18F-FDG PET/CT in Newly Diagnosed Secondary Hemophagocytic Lymphohistiocytosis

Publication: Ann Nucl Med. 2021 Mar;35(3):386-96. PMID: 33469854

Authors: Liu J, Yang X, Yang J.

Institution: Department of Urology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China.

Abstract: We retrospectively collected 58 patients with newly diagnosed SHLH from August 2016 to July 2019 in our hospital. All patients were followed up between 6 and 24 months. First, a comprehensive comparison of the general data between the death and the survival group was performed. Clinical lab indexes included were recorded and analyzed retrospectively. Second, the correlation between 18F-FDG PET/CT semiquantitative metabolic parameters of VAT, SAT and inflammatory cytokines was performed. 3D Slicer software was used to get SUV and volume of VAT and SAT from 18F-FDG PET/CT. Third, overall survival (OS) analysis was performed. Finally, the prognosis predicting model was built based on risk factors to stratify SHLH patients.

An Open-Source Three-Dimensionally Printed Laryngeal Model for Injection Laryngoplasty Training

Publication: Laryngoscope. 2021 Mar;131(3):E890-E895. PMID: 32750164

Authors: Lee M, Ang C, Andreadis K, Shin J, Rameau A.

Institution: Sean Parker Institute for the Voice, Department of Otolaryngology-Head and Neck Surgery, Weill Cornell Medicine, New York, NY, USA.

Abstract: Computed tomography scans of the upper airways were processed with 3D Slicerto generate a computer model of the endolarynx. Blender and Fusion 360 were used to refine the mucosal model and develop casts for silicone injection molding. The casted endolaryngeal structures were inserted into a modified version of a publicly available laryngeal cartilage model. The final models were evaluated by 10 expert laryngologists using a customized version of the Michigan Standard Simulation Experience Scale. Internal consistency and interrater reliability of the survey were evaluated using Cronbach's α and intraclass correlation, respectively.

Treatment Measures of Hemimandibular Hyperplasia and Associated Facial Deformities

Publication: J Craniomaxillofac Surg. 2021 Feb;49(2):126-34. PMID: 33451941

Authors: Abotaleb B, Bi R, Telha W, Zhao W, Li Y, Zhu S.

Institution: State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.

Abstract: This study aims to show our institute's experience in the treatment of HH and its associated facial deformities in adults and growing adolescents and to investigate condylar remodeling and volumetric changes and long-term stability of orthognathic surgery in adults. The study included consecutive patients with clinical and radiological features of HH who underwent high condylectomy with or without simultaneous orthognathic surgery from 2013 to 2018. The clinical outcomes were assessed based on functional activities, TMJ pain, and recurrence. Postoperative 3D condylar remodeling and orthognathic stability were evaluated with the use of ITK-Snap and 3D Slicer. Thirteen patients (8 females and 5 males) with a mean age of 26.3 ± 5.79 years (range; 13-34 years) were included with facial asymmetry as the chief complaint. The patients were followed up for a minimum of 12 months and a maximum of 4 years (mean; 16.85 ± 10.04). There were no postoperative complications, and all patients achieved a satisfactory functional and aesthetic outcome using a one-stage surgical procedure. There was no incidence of recurrence or further asymmetries, with long-term stability at the selected points showing a mean difference of less than ±1 mm. The affected condylar volume was significantly reduced following high condylectomy, with mean changes between T1 and T2 of -144. 80 mm3 (p = .012). However, the contralateral condylar volume remained stable, with a mean change of 2.54 mm3 (p = .881). One-stage high condylectomy and orthognathic surgery is a viable measure for the treatment of HH and associated deformities in adults. High condylectomy in early adolescence could result in termination of the disease, and aesthetic improvement with further constant orthodontist-surgeon follow-up is required.

Three-Dimensional Evaluation of Dental Decompensation and Mandibular Symphysis Remodeling on Orthodontic-Surgical Treatment of Class III Malocclusion

Publication: Am J Orthod Dentofacial Orthop. 2021 Feb;159(2):184-92. PMID: 33388202 | PDF

Authors: Sendyk M, Cevidanes LHS, Ruellas ACO, Fattori L, Mendes FM, Paiva JB, Rino Neto J.

Institution: Department of Orthodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil.

Abstract: The sample consisted of 30 adults with Class III dentofacial deformity, who had presurgical orthodontic treatment. Three-dimensional images were generated by cone-beam computed tomography scans at 2 different times (initial and before orthognathic surgery). Three-dimensional virtual models were obtained and superimposed using automated voxel-based registration at the mandible to evaluate B-point displacement, mandibular molar and incisor decompensation movement, and symphysis inclination and thickness. The 3-dimensional displacements of landmarks at the symphysis were quantified and visualized with color-coded maps using 3D Slicer v.4.0. software.

A CT-Based Radiomics Nomogram for Distinguishing Between Benign and Malignant Bone Tumours

Publication: Cancer Imaging. 2021 Feb 6;21(1):20. PMID: 33549151 PDF

Authors: Sun W, Liu S, Guo J, Liu S, Hao D, Hou F, Wang H, Xu W.

Institution: Department of Radiology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.

Abstract: Background: We sought to evaluate the performance of a computed tomography (CT)-based radiomics nomogram we devised in distinguishing benign from malignant bone tumours.

Methods: Two hundred and six patients with bone tumours were spilt into two groups: a training set (n = 155) and a validation set (n = 51). A feature extraction process based on 3D Slicer software was used to extract the radiomics features from unenhanced CT images, and least absolute shrinkage and selection operator logistic regression was used to calculate the radiomic score to generate a radiomics signature. A clinical model comprised demographics and CT features. A radiomics nomogram combined with the clinical model and the radiomics signature was constructed. The performance of the three models was comprehensively evaluated from three aspects: identification ability, accuracy, and clinical value, allowing for generation of an optimal prediction model.

A Supplemental Technique for Preoperative Evaluation of Giant Intracranial Aneurysm

Publication: J Neurol Surg A Cent Eur Neurosurg. 2021 Feb 14. PMID: 33583010

Authors: Wang HW, Wu C, Xue Z, Shu XJ, Sun ZH.

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

Abstract: Preoperative planning mainly relies on digital subtraction angiography (DSA) and computed tomography angiography. However, neither technique can reveal thrombi in giant intracranial aneurysms (GIAs). In this study, we aimed to reconstruct the circulating and noncirculating parts of GIAs with the time-of-flight (TOF) and motion-sensitized driven-equilibrium (MSDE) sequences with 3D Slicer to reveal an integrated presentation of GIAs, compare its accuracy, and validate the usefulness for preoperative planning.

Maxillary Dentoskeletal Outcomes of the Expander With Differential Opening and the Fan-Type Expander: A Randomized Controlled trialA Supplemental Technique for Preoperative Evaluation of Giant Intracranial Aneurysm

Publication: Clin Oral Investig. 2021 Feb 12. PMID: 33580351

Authors: Massaro C, Garib D, Cevidanes L, Janson G, Yatabe M, Lauris JRP, Ruellas AC.

Institution: Department of Orthodontics, Bauru Dental School, University of São Paulo, Brazil.

Abstract: The aim of this study was to compare the maxillary dentoskeletal outcomes of the expander with differential opening (EDO) and the fan-type expander (FE).

Material and methods: Forty-eight patients with maxillary arch constriction in the mixed dentition were randomly allocated into EDO and FE groups. Cone-beam computed tomography scans were acquired before and after expansion. Linear and angular three-dimensional changes were assessed after cranial base superimposition using the ITK-SNAP and the 3D Slicer software. T or Mann-Whitney U tests were used for intergroup comparisons (P<0.05).

Positron Emission Tomography-Based Short-Term Efficacy Evaluation and Prediction in Patients With Non-Small Cell Lung Cancer Treated With Hypo-Fractionated Radiotherapy

Publication: Front Oncol. 2021 Feb 25;11:590836. PMID: 33718144 | PDF

Authors: Jiang YQ, Gao Q, Chen H, Shi XX, Wu JB, Chen Y, Zhang Y, Pang HW, Lin S.

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

Abstract: The 3D Slicer was used to extract the radiomics features based on positron emission tomography. Least absolute shrinkage and selection operator regression was used to eliminate redundant features, and logistic regression analysis was used to develop the curative-effect-predicting model, which was displayed through a radiomics nomogram. Receiver operating characteristic curve and decision curve were used to evaluate the accuracy and clinical usefulness of the prediction model.

Radiomics-Based Machine Learning Model to Predict Risk of Death Within 5-Years in Clear Cell Renal Cell Carcinoma Patients

Publication: Comput Biol Med. 2021 Feb;129:104135. PMID: 33254045

Authors: Nazari M, Shiri I, Zaidi H.

Institution: Department of Biomedical Engineering and Medical Physics, Shahid Beheshti University of Medical Sciences, Tehran, Iran.

Abstract: According to image quality and clinical data availability, we eventually selected 70 ccRCC patients that underwent CT scans. Manual volume-of-interest (VOI) segmentation of each image was performed by an experienced radiologist using the 3D Slicer software package. Prior to feature extraction, image pre-processing was performed on CT images to extract different image features, including wavelet, Laplacian of Gaussian, and resampling of the intensity values to 32, 64 and 128 bin levels. Overall, 2544 3D radiomics features were extracted from each VOI for each patient. Minimum Redundancy Maximum Relevance (MRMR) algorithm was used as feature selector. Four classification algorithms were used, including Generalized Linear Model (GLM), Support Vector Machine (SVM), K-nearest Neighbor (KNN) and XGBoost. We used the Bootstrap resampling method to create validation sets. Area under the receiver operating characteristic (ROC) curve (AUROC), accuracy, sensitivity, and specificity were used to assess the performance of the classification models.

Exploring the Variability of Radiomic Features of Lung Cancer Lesions on Unenhanced and Contrast-Enhanced Chest CT Imaging

Publication: Phys Med. 2021 Feb;82:321-31. PMID: 33721791

Authors: Tamponi M, Crivelli P, Montella R, Sanna F, Gabriele D, Poggiu A, Sanna E, Marini P, Meloni GB, Sverzellati N, Conti M.

Institution: Health Physics Unit, ATS Sardinia Regional Health Service, Sassari, Italy.

Abstract: Chest CT scans, unenhanced and contrast-enhanced, of 17 patients were selected from images collected as part of the staging process. The major T1-T3 lesion was contoured through a semi-automatic approach. These lesions formed the lesion phantoms to study features behavior. The stability of 94 features of the 3D Slicerr package Radiomics was analyzed. Feature discrimination power was quantified by means of Gini's coefficient. Correlation between distance matrices was evaluated through Mantel statistic. Heatmap, cluster and silhouette plots were applied to find well-structured partitions of lesions.

Regenerative Orthodontics: GBR and Corticotomy to Stretch the Limits of Orthodontic Treatment

Publication: Int J Periodontics Restorative Dent. 2021 Jan-Feb;41(1):105-11. PMID: 33528458

Authors: Brugnami F, Caiazzo A, Signorelli L, Capri D.


Abstract: Orthodontic therapy could lead to marginal bone resorption in cases where the teeth are moved outside the envelope of bone. The purpose of this case series was to test corticotomy with a guided bone regeneration (GBR) procedure to regenerate bone in the direction of movement outside the original bony housing. Ten adult patients (60 anterior teeth), all presenting with severe anterior crowding, were enrolled in the study. Orthodontic therapy in all investigated sites was associated with selective surgical corticotomies and a simultaneous GBR procedure. CBCT examinations were performed before starting orthodontic treatment (T0) and at the end of treatment (T1; mean: 7 months; range: 6 to 9 months). Pre- and postoperative CBCTs were superimposed with a DICOM viewer 3D Slicer and studied with an image-processing software (ImageJ, National Institutes of Health) to measure the area of interest of the buccal plate. The average area was found to be 0.58 ± 0.22 mm2 at T0 and 1.76 ± 0.4 mm2 at T1, with a statistically significant difference (P < .05). The combination of corticotomy and a regenerative procedure seems to have the ability to augment the original osseous anatomy when the root is moved outside of the original bony envelope.

The Effects of Age and Race on Calvarium, Tegmen, and Zygoma Thickness

Publication: J Craniofac Surg. 2021 Jan-Feb 01;32(1):345-9. PMID: 32890157

Authors: Saltagi MZ, Schueth E, Nag A, Rabbani C, MacPhail ME, Nelson RF.

Institution: Department of Neurosurgery, Indiana University School of Medicine, Indianapolis, IN, USA.

Abstract: A total of 446 patients with high-resolution head computer tomography (CT) imaging from 2003 to 2018.Intervention(s): Calvarial, tegmen, and zygoma thicknesses were measured using 3D Slicer. Main Outcome Measure(s): Effects of age and race on calvarium, tegmen, zygoma thickness.

Novel Workflow for Conversion of Catheter-Based Electroanatomic Mapping to DICOM Imaging for Noninvasive Radioablation of Ventricular Tachycardia

Publication: Pract Radiat Oncol. 2021 Jan-Feb;11(1):84-8. PMID: 32416269

Authors: Brett CL, Cook JA, Aboud AA, Karim R, Shinohara ET, Stevenson WG.

Institution: Department of Radiation Oncology, Vanderbilt University Medical Center, Nashville, TN, USA.

Abstract: The raw data export of the CARTO3 EAM system (version 6.0.45.171, ".mesh" file) was processed with a MATLAB script to generate 3-dimensional (3D) visual took kit files containing X, Y, Z coordinates obtained during mapping and corresponding impedance, voltage, and other point-based information. The image could then be visualized with standard image processing software, 3D Slicer and the target outlined on the image surface. This structure was in turn converted to a DICOM image and fused with patient thoracic imaging using anatomic landmarks. Robustness of the workflow was assessed through implementation with a second magnetic resonance imaging based VT ablation planning system, ADAS-VT.

Deformation of the Pelvic Arteries Caused by Pneumoperitoneum and Postural Changes in an Animal Model

Publication: In Vivo. 2021 Jan-Feb;35(1):275-81. PMID: 33402474 | PDF

Authors: Kiyomatsu H, Ma L, Wang J, Kiyomatsu T, Tsukihara H, Kobayashi E, Sakuma I, Ishihara S.

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

Abstract: Computed tomography images of pigs were acquired in different body positions (supine, head down at 5° and 10°, right lateral recumbent at 5° and 15°) before and after insufflation. We used a free software, 3D Slicer, for image analysis. After landmark registration using 10 markers inserted into the pelvis, pelvic arterial deformation and shift of seven arterial bifurcation points were evaluated. The distance moved was the target registration error (TRE) from the points registered in the supine position. Fiducial registration error (FRE) was measured using the 10 pelvic markers.

CardIAc: An Open-Source Application for Myocardial Strain Analysis

Publication: Int J Comput Assist Radiol Surg. 2021 Jan;16(1):65-79. PMID: 33196972

Authors: Curiale AH, Bernardo A, Cárdenas R, Mato G.

Institution: Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.

Abstract: CardIAc was developed as a 3D Slicer extension for an easy installation and usability. The main contribution of this article is to provide a general workflow, going from data and segmentation loading, 3D heart modeling, analysis and several options for visualization of the myocardial strain.

Endoscope-Assisted Fluorescence-Guided Resection Allowing Supratotal Removal in Glioblastoma Surgery

Publication: Neurosurg Focus. 2021 Jan;50(1):E3. PMID: 33386004

Authors: Bettag C, Schregel K, Langer P, Thomas C, Behme D, Stadelmann C, Rohde V, Mielke D.

Institution: Department of Neuroradiology, University Hospital Heidelberg, Germany.

Abstract: The authors conducted a retrospective single-center analysis of a consecutive series of patients with primary GBM presumed to be noneloquently located and routinely operated on at their institution between January 2015 and February 2018 using a combined microscopic and endoscopic FG resection. A 20-mg/kg dose of 5-aminolevulinic acid (5-ALA) was administered 4 hours before surgery. After complete microscopic FG resection, the resection cavity was scanned using the endoscope. Detected residual fluorescent tissue was resected and embedded separately for histopathological examination. Nonenhanced and contrast-enhanced 3D T1-weighted MR images acquired before and within 48 hours after tumor resection were analyzed using 3D Slicer. Bias field-corrected data were used to segment brain parenchyma, contrast-enhancing tumor, and the resection cavity for volume definition. The difference between the pre- and postoperative brain parenchyma volume was considered to be equivalent to the resected nonenhancing but fluorescent tumor tissue. The volume of resected tumor tissue was calculated from the sum of resected contrast-enhancing tumor tissue and resected nonenhancing tumor tissue.

Clinical and Radiological Predictors of Epidermal Growth Factor Receptor Mutation in Nonsmall Cell Lung Cancer

Publication: J Appl Clin Med Phys. 2021 Jan;22(1):271-80. PMID: 33314737 | PDF

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

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

Abstract: Patients with NSCLC who underwent EGFR mutation detection between 2014 and 2017 were included. Clinical features and general imaging features were collected, and radiomic features were extracted from CT data by 3D Slicer software. Prognostic factors of EGFR mutation status were selected by least absolute shrinkage and selection operator (LASSO) logistic regression analysis, and receiver operating characteristic (ROC) curves were drawn for each prediction model of EGFR mutation.

A User-Friendly Protocol for Mandibular Segmentation of CBCT Images for Superimposition and Internal Structure Analysis

Publication: J Clin Med. 2021 Jan 1;10(1):127. PMID: 33401443 | PDF

Authors: Li C, Lin L, Zheng Z, Chung CH.

Institution: Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, USA.

Abstract: The "sculpting tool" in the Dolphin 3D Imaging software was used for segmentation. The segmented mandible images were saved as STL files for volume matching in the 3D Slicer to validate the repeatability of the current protocol and were exported as DICOM files for internal structure analysis and voxel-based superimposition.

Development, Validation, and Pilot MRI Safety Study of a High-Resolution, Open Source, Whole Body Pediatric Numerical Simulation Model

Publication: PLoS One. 2021 Jan 13;16(1):e0241682. PMID: 33439896 | PDF

Authors: Jeong H, Ntolkeras G, Alhilani M, Atefi SR, Zöllei L, Fujimoto K, Pourvaziri A, Lev MH, Grant PE, Bonmassar G.

Institution: Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.

Abstract: Numerical body models of children are used for designing medical devices, including but not limited to optical imaging, ultrasound, CT, EEG/MEG, and MRI. These models are used in many clinical and neuroscience research applications, such as radiation safety dosimetric studies and source localization. Although several such adult models have been reported, there are few reports of full-body pediatric models, and those described have several limitations. Some, for example, are either morphed from older children or do not have detailed segmentations. Here, we introduce a 29-month-old male whole-body native numerical model, "MARTIN", that includes 28 head and 86 body tissue compartments, segmented directly from the high spatial resolution MRI and CT images. An advanced auto-segmentation tool was used for the deep-brain structures, whereas 3D Slicer was used to segment the non-brain structures and to refine the segmentation for all of the tissue compartments. Our MARTIN model was developed and validated using three separate approaches, through an iterative process, as follows. First, the calculated volumes, weights, and dimensions of selected structures were adjusted and confirmed to be within 6% of the literature values for the 2-3-year-old age-range. Second, all structural segmentations were adjusted and confirmed by two experienced, sub-specialty certified neuro-radiologists, also through an interactive process. Third, an additional validation was performed with a Bloch simulator to create synthetic MR image from our MARTIN model and compare the image contrast of the resulting synthetic image with that of the original MRI data; this resulted in a "structural resemblance" index of 0.97. Finally, we used our model to perform pilot MRI safety simulations of an Active Implantable Medical Device (AIMD) using a commercially available software platform (Sim4Life), incorporating the latest International Standards Organization guidelines. This model will be made available on the Athinoula A. Martinos Center for Biomedical Imaging website.

Condylar Changes in Children with Posterior Crossbite after Maxillary Expansion: Tridimensional Evaluation

Publication: Children (Basel). 2021 Jan 11;8(1):38. PMID: 33440762 | PDF

Authors: Fastuca R, Turiaco H, Assandri F, Zecca PA, Levrini L, Caprioglio A.

Institution: Department of Biomedical, Surgical and Dental Sciences, University of Milan, 20122 Milan, Italy.

Abstract: To investigate condylar position in subjects with functional posterior crossbite comparing findings before and after rapid maxillary expansion (RME) treatment through 3D analysis. Methods: Thirty-two Caucasian patients (14 males, mean age 8 y 8 m ± 1 y 2 m; 18 females mean age 8 y 2 m ± 1 y 4 m) with functional posterior crossbite (FPXB) diagnosis underwent rapid palatal expansion with a Haas appliance banded on second deciduous upper molars. Patients' underwent CBCT scans before rapid palatal expansion (T0) and after 12 months (T1). The images were processed through 3D Slicer software; Results: The condylar position changes between T1 and T0 among the crossbite and non-crossbite sides were not statistically significant, except for the transversal axis. At T1, the condyles moved forward (y axis) and laterally (x axis), they also moved downward (z axis) but not significantly; (4) Conclusions: Condilar position in growing patients with functional posterior crossbite did not change significantly after rapid maxillary expansion.

New Insights Into Intrinsic Foot Muscle Morphology and Composition Using Ultra-High-Field (7-Tesla) Magnetic Resonance Imaging

Publication: BMC Musculoskelet Disord. 2021 Jan 21;22(1):97. PMID: 33478467 | PDF

Authors: Franettovich Smith MM, Elliott JM, Al-Najjar A, Weber KA 2nd, Hoggarth MA, Vicenzino B, Hodges PW, Collins NJ.

Institution: School of Health and Rehabilitation Sciences, The University of Queensland, QLD, Australia

Abstract: One healthy female (age 39 years, mass 65 kg, height 1.73 m) underwent MRI. A T1-weighted VIBE - radio-frequency spoiled 3D steady state GRE - sequence of the whole foot was acquired on a Siemens 7T MAGNETOM scanner, as well as a 3T MAGNETOM Prisma scanner for comparison. A high-resolution fat/water separation image was also acquired using a 3D 2-point DIXON sequence at 7T. Coronal plane images from 3T and 7T scanners were compared. Using 3D Slicer software, regions of interest were manually contoured for each muscle on 7T images. Muscle volumes and percentage of muscle fat infiltration were calculated (muscle fat infiltration % = Fat/(Fat + Water) x100) for each muscle.

3D-Volume Rendering of the Pelvis With Emphasis on Paraurethral Structures Based on MRI Scans and Comparisons Between 3D Slicer and OsiriX®

Publication: AJ Med Syst. 2021 Jan 20;45(3):27. PMID: 33469726 | PDF

Authors: Durnea CM, Siddiqi S, Nazarian D, Munneke G, Sedgwick PM, Doumouchtsis SK.

Institution: Epsom & St. Helier University Hospitals NHS Trust, Epsom, UK.

Abstract: The feasibility of rendering three dimensional (3D) pelvic models of vaginal, urethral and paraurethral lesions from 2D MRI has been demonstrated previously. To quantitatively compare 3D models using two different image processing applications: 3D Slicer and OsiriX. Secondary analysis and processing of five MRI scan based image sets from female patients aged 29–43 years old with vaginal or paraurethral lesions. Cross sectional image sets were used to create 3D models of the pelvic structures with 3D Slicer and OsiriX image processing applications. The linear dimensions of the models created using the two different methods were compared using Bland-Altman plots. The comparisons demonstrated good agreement between measurements from the two applications. The two data sets obtained from different image processing methods demonstrated good agreement. Both 3D Slicer and OsiriX can be used interchangeably and produce almost similar results. The clinical role of this investigation modality remains to be further evaluated.

Shape of the Cochlear Basal Turn: An Indicator for an Optimal Electrode-to-Modiolus Proximity With Precurved Electrode Type

Publication: Ear Nose Throat J. 2021 Jan;100(1):38-43. PMID: 32330070 | PDF

Authors: Khurayzi T, Dhanasingh A, Almuhawas F, Alsanosi A.

Institution:King Abdullah Ear Specialist Center, 37850King Saud University, Riyadh, Saudi Arabia.

Abstract: Computed tomography (CT) preoperative image-data sets of 117 ears were made available for the measurements of cochlear parameters retrospectively. 3D Slicer was used in the visualization and measurement of cochlear parameters from both 3D and 2D (2-dimensional) images of the inner ear. Cochlear parameters including basal turn diameter (A), width of the basal turn (B), and cochlear height (H) were measured from the appropriate planes. B/A ratio was made to investigate which ratios correspond to round and elliptical shape of the cochlear basal turn.

The Use of Magnetic Resonance Imaging Technique and 3D Printing in Order to Develop a Three-Dimensional Fistula Model for Patients With Crohn's Disease: Personalised Medicine

Publication: Prz Gastroenterol. 2021;16(1):83-88. PMID: 33986892

Authors: Guz W, Ożóg Ł, Aebisher D, Filip R.

Institution: Department of Electroradiology, Medical College of Rzeszów University, University of Rzeszow, Rzeszow, Poland.

Abstract: MRI at 1.5T and a 3D printer were used. DICOM (Digital imaging and communications in medicine) images were imported into 3D Slicer v.4.8.0. Firstly, anal fistula was modelled on the basis of axial images. Fistula locations, the anus and anal canal, were marked with different coloured markers.

Impact of 3D Printing in Surgical Planning of Congenital Heart Disease

Publication: Arch Cardiol Mex. 2021;91(1):1-6. PMID: 33661871

Authors: Cano-Zárate R, Hernández-Barajas EK, Hernández-Barajas HH, Meave-González A, Espínola-Zavaleta N.

Institution: Departamento de Cardiología Nuclear, Instituto Nacional de Cardiología Ignacio Chávez. Ciudad de México, México.

Abstract: Congenital heart disease makes up for 30% of all congenital anomalies. The prevalence is 8/1,000 live newborns, without predominance of gender. Imaging methods such as echocardiography, angiography, computed tomography or magnetic resonance imaging must be routinely used in congenital heart disease. The mentioned methods can provide virtual reconstructions in volumetric reconstruction or in three dimensional (3D), but only 3D-printed heart models can provide real 3D tactile replicas of cardiac anatomy.

Objective: To make 3D printed heart models in order to provide real 3D tactile replicas of the cardiac anatomy that allow a detailed visualization from all possible perspectives, either of extracardiac or intracardiac structures.

Methods: This information is useful for surgical decision making, especially in patients with complex cardiac defects. DICOM, edited in a software package 3D Slicer v.4.3 and exported for printing in file format (.stl).

Results and conclusions: With 3D printing, the intracardiac and extracardiac anatomy can be evaluated in detail with real-scale cardiac models of the patient, avoiding unexpected findings. This technique is very useful especially in complex congenital heart defects, since it allows precise planning of the surgical procedure.

Association of White Matter Hyperintensity Progression with Cognitive Decline in Patients with Amnestic Mild Cognitive Impairment

Publication: J Alzheimers Dis. 2021;80(2):877-83. PMID: 33579856 PDF

Authors: Hirao K, Yamashita F, 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, Shinjuku-ku, Tokyo, Japan.

Abstract: Background: White matter hyperintensities (WMH) on MRI have been reported to increase the risk of conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD). However, effects of the progression of WMH on the cognition of patients with MCI remains unclear to date.

Objective: To investigate the association between WMH progression and cognitive decline in amnestic MCI patients.

Methods: Thirty-eight subjects with amnestic MCI were analyzed prospectively every year for 2 years. Fourteen MCI subjects dropped out on the final visit, and therefore 24 subjects with MCI were analyzed for the entire duration. The volumes of periventricular hyperintensities (PVH) and deep WMH (DWMH) were measured on T2 FLAIR using the 3D Slicer. The associations between PVH/DWMH progression and cognitive decline were investigated.

Results: An increase in DWMH volume significantly correlated with changes in Mini-Mental State Examination and category verbal fluency scores, whereas an increase in PVH volume did not correlate with changes in any item.

Conclusion: DWMH progression was closely associated with a decline in frontal lobe function and semantic memory, suggesting that WMH progression might affect some AD pathophysiologies in amnestic MCI patients.