Three-dimensional Anatomical Model Research Articles

Immersive Photorealistic Three-Dimensional Neurosurgical Anatomy of the Cerebral Arteries: A Photogrammetry-Based Anatomic Study.

Neurosurgeons need a profound knowledge of the surgical anatomy of the cerebral arteries to safely treat patients. This is a challenge because of numerous branches, segments, and tortuosity of the main blood vessels that supply the brain. The objective of this study was to create high-quality three-dimensional (3D) anatomic photorealistic models based on dissections of the brain arterial anatomy and to incorporate this data into a virtual reality (VR) environment. Two formaldehyde-fixed heads were used. The vessels were injected with radiopaque material and colored silicone and latex. Before the dissections, the specimens were computed tomography scanned. Stratigraphical anatomic dissection of the neck and brain was performed to present the relevant vascular anatomy. A simplified surface scanning method using a mobile phone-based photogrammetry application was used, and the data were incorporated into a VR 3D modeling software for post-processing and presentation. Fifteen detailed layered photorealistic and two computed tomography angiography-based 3D models were generated. The models allow manipulation in VR environment with sufficient photographic detail to present the structures of interest. Topographical relevant anatomic structures and landmarks were annotated and uploaded for web-viewing and in VR. Despite that the VR application is a dedicated 3D modeling platform, it provided all necessary tools to be suitable for self-VR study and multiplayer scenarios with several participants in one immersive environment. Cerebral vascular anatomy presented with photogrammetry surface scanning method allows sufficient detail to present individual vessel's course and even small perforating arteries in photorealistic 3D models. These features, including VR visualization, provide new teaching prospects. The whole study was done with simplified algorithms and free or open-source software platforms allowing creation of 3D databases especially useful in cases with limited body donor-based dissection training availability.

Efficient musculoskeletal annotation using free-form deformation

Traditionally, constructing training datasets for automatic muscle segmentation from medical images involved skilled operators, leading to high labor costs and limited scalability. To address this issue, we developed a tool that enables efficient annotation by non-experts and assessed its effectiveness for training an automatic segmentation network. Our system allows users to deform a template three-dimensional (3D) anatomical model to fit a target magnetic-resonance image using free-form deformation with independent control points for axial, sagittal, and coronal directions. This method simplifies the annotation process by allowing non-experts to intuitively adjust the model, enabling simultaneous annotation of all muscles in the template. We evaluated the quality of the tool-assisted segmentation performed by non-experts, which achieved a Dice coefficient greater than 0.75 compared to expert segmentation, without significant errors such as mislabeling adjacent muscles or omitting musculature. An automatic segmentation network trained with datasets created using this tool demonstrated performance comparable to or superior to that of networks trained with expert-generated datasets. This innovative tool significantly reduces the time and labor costs associated with dataset creation for automatic muscle segmentation, potentially revolutionizing medical image annotation and accelerating the development of deep learning-based segmentation networks in various clinical applications.

Everyone can draw: An inclusive and transformative activity for conceptualization of topographic anatomy.

Anatomical drawing traditionally involves illustration of labeled diagrams on two-dimensional surfaces to represent topographical features. Despite the visual nature of anatomy, many learners perceive that they lack drawing skills and do not engage in art-based learning. Recent advances in the capabilities of technology-enhanced learning have enabled the rapid and inexpensive production of three-dimensional anatomical models. This work describes a "drawing on model" activity in which learners observe and draw specific structures onto three-dimensional models. Sport and exercise sciences (SES, n = 79) and medical (MED, n = 156) students at a United Kingdom medical school completed this activity using heart and femur models, respectively. Learner demographics, their perceptions of anatomy learning approaches, the value of the activity, and their confidence in understanding anatomical features, were obtained via validated questionnaire. Responses to 7-point Likert-type and free-text items were analyzed by descriptive statistics and semi-quantitative content analysis. Learners valued art-based study (SES mean = 5.94 SD ±0.98; MED = 5.92 ± 1.05) and the "drawing on model" activity (SES = 6.33 ± 0.93; MED = 6.21 ± 0.94) and reported enhanced confidence in understanding of cardiac anatomy (5.61 ± 1.11), coronary arteries (6.03 ± 0.83), femur osteology (6.07 ± 1.07), and hip joint muscle actions (5.80 ± 1.20). Perceptions of learners were independent of both their sex and their art-based study preferences (p < 0.05). Themes constructed from free-text responses identified "interactivity," "topography," "transformative," and "visualization," as key elements of the approach, in addition to revealing some limitations. This work will have implications for anatomy educators seeking to engage learners in an inclusive, interactive, and effective learning activity for supporting three-dimensional anatomical understanding.

Creation of Three-dimensional Anatomic Models in Pediatric Surgical Patients Using Cross-sectional Imaging: A Demonstration of Low-cost Methods and Applications

BackgroundPediatric surgery patients often present with complex congenital anomalies or other conditions requiring deep understanding of their intricate anatomy. Commercial applications and services exist for the conversion of cross-sectional imaging data into three-dimensional (3D) models for education and preoperative planning. However, the associated costs and lack of familiarity may discourage their use in centers with limited resources. The purpose of this report is to present a low-cost, reproducible method for generating 3D images to visualize patient anatomy. MethodsDe-identified DICOM files were obtained from the hospital PACS system in preparation for assorted pediatric surgical procedures. Using open-source visualization software, variations in anatomic structures were examined using volume rendering and segmentation techniques. Images were further refined using available editing tools or artificial intelligence-assisted software extensions. ResultsUsing the described techniques we were able to obtain excellent visualization of desired structures and associated anatomic variations. Once structures were selected and modeled in 3D (segmentation), they could be exported as one of several 3D object file formats. These could then be retained for 3D printing, visualization in virtual reality, or as an anatomic reference during the perioperative period. Models may also be imported into commercial gaming engines for rendering under optimal lighting conditions and with enhanced detail. ConclusionPediatric surgeons are frequently tasked with the treatment of patients with complex and rare anomalies. Visualization and preoperative planning can be assisted by advanced imaging software at minimal to no cost, thereby facilitating enhanced understanding of these conditions in resource-limited environments. Level of EvidenceV, Case Series, Description of Technique.

Mean S1 inlet and outlet view angles are not safe for all individuals according to three-dimensional tomographic measurements.

Although there are many studies evaluating optimal inlet and outlet angles required for the correct placement of S1 iliosacral screws, there is no study evaluating reliability and feasibility of these angles for all individuals on three-dimensional (3D) anatomical models. A total of 100 women and 100 men were selected randomly. A vertical line was created according to long axis of the tomography device on which patient was lying in supine position. The automatized best-fit planes were created on superior and inferior endplates, anterior cortex including notch region and posterior cortex of first sacral vertebrae using 3D imaging software to measure mean inlet and outlet angles. We observed no statistically significant difference between gender groups in terms of inlet and outlet angles. Mean inlet view is obtained for anterior cortex of S1 in 22.5 ± 9.5° and for posterior cortex in 46.5 ± 9.3°. Mean fluoroscopic view angle of S1 for superior outlet is 40.3 ± 7.6 and for inferior outlet is 46.9 ± 8.8. Mean anterior and posterior S1 inlet view angles do not accurately visualize anterior cortex of 74 (37%) and posterior cortex of 66 (33%) individuals. Mean superior and inferior S1 outlet view angles do not accurately visualize superior endplate of 74 (37%) and inferior endplate of 56 (28%) individuals. Due to individual alterations of spatial position of sacrum, mean inlet and outlet view angles of S1 are not sufficient to visualize the iliosacral screws under fluoroscopy in many individuals.

Mixed Reality for Pediatric Brain Tumors: A Pilot Study from a Singapore Children’s Hospital

Mixed reality (MR) platforms for neurosurgical education, training, and clinical use have gained popularity in recent years. However, their use in pediatric neurosurgery is comparatively unexplored. We designed a study to explore the use of an MR-based application for pediatric brain tumors. The primary aim is to determine if the use of MR provides the neurosurgical team with a better understanding of the visuospatial anatomy of neoplasms in pediatric craniums and to guide operative planning. Secondary aims include exploring its use as an educational tool for junior doctors and medical students. Methods: Three-dimensional anatomical models of selected pediatric brain tumors are created and uploaded to an MR application. The processed data is transferred into designated MR head-mounted devices. At the end of the trial, users are required to fill in an evaluation form. Results: A total of 30 participants took part in this study. Based on the collated feedback data, all of them agreed that the MR platform was useful as a tool in different aspects of understanding the selected pediatric brain tumors. Conclusions: This study demonstrates a proof of concept of the feasibility of MR platforms for a better understanding of pediatric brain tumors. Further development is needed to refine the current setup to be more versatile.

Left atrium surface mesh reconstruction from cardiac MRI

Abstract Funding Acknowledgements Type of funding sources: None. Background The strive towards personalised medicine is universal across all aspects of healthcare. In the management of atrial fibrillation (AF), this can take the form of shape analysis tools to predict an individual’s outcome from catheter ablation (1–3), or electrophysiological simulations to plan an ablation strategy (4–6). Fundamental to their application is our ability to derive accurate three-dimensional (3D) anatomical models of a patient’s left atrial geometry from cross-sectional imaging. MRI is widely utilised in this regard due to its excellent tissue characterisation. However, constructing surface meshes can be challenging given its relatively sparse two-dimensional (2D) image planes. A particular challenge exists in producing a mesh that balances concordance with left atrium segmentation and smoothing terms to eliminate sharp edges and artifact from the contouring process. Objective Here, we describe a novel method for left atrium surface mesh reconstruction from MRI contours. Methods Cardiac MRI was performed on ten patients with paroxysmal or persistent AF, on a 3T clinical MR scanner using phased-array receiver coils. Image sequences included respiratory and ECG-gated 15-minute post contrast late gadolinium enhancement, with a 1.3mm slice thickness and in-plane resolution of 0.66×0.66mm2. Seven individuals were in sinus rhythm, and three in AF at the time of MRI. A single, custom, graphical interface tool implemented in Matlab R2014a enabled 3D mesh reconstruction from 2D MRI slices (7,8). Endocardial surfaces of the left atrium were manually segmented by an experienced clinician, with the pulmonary veins and left atrial appendage excluded at their ostia (Figure 1A). Our tool produced an initial sparse representation with vertices equally spaced along the contours (Figure 1B). Attractor points were defined along the contours, with subdivision and Laplacian smoothing applied to the mesh. This was balanced with a deformation step, which iteratively pulled the mesh towards the attractor points (Figure 1C), resulting in its final shape (Figure 1D). Results Reconstruction performance was evaluated by measuring the distance between heart contours and the reconstructed 3D surface for each case, producing the value for average misalignment 0.71 ± 0.58mm, which compares favourably to the in-plane resolution. Conclusions Our approach offers a highly accurate method for producing 3D anatomical models of the left atrium from MRI, which is fully automated following segmentation through an interactive graphical interface. The iterative optimisation between attractor-based deformation towards the original contours and the Laplacian smoothing enables us to create smooth geometries which remain true to their segmentations. Furthermore, our approach does not require the use of a template mesh, which can result in final geometries being biased towards the template.

Numerical simulations for characterization of missing articulatory information in ultrasound imaging of speech

The air–tissue interface at the tongue surface allows submental (below the chin) B-mode ultrasound images to depict the shape of the tongue in real time, useful for measuring and understanding typical and disordered tongue articulation during speech production. However, parts of the tongue are obscured; depending on an individual speaker's anatomy and tongue movement patterns, the anterior tongue tip may be shadowed by the mandible bone and the sublingual airspace. To characterize this missing information about the tongue tip in ultrasound images, midsagittal ultrasound images were numericallysimulated. Three-dimensional anatomic models were constructed using magnetic resonance imaging (MRI) data to map tongue tissue, surrounding air, and an estimated position of the mandible. Pulse-echo ultrasound images were then numerically simulated using the open-source k-Wave toolbox. Acoustic properties of the medium and an imaging array model are identified that allow simulations to replicate features in ultrasound images recorded from the same speakers as the MRI data, while maintaining computational efficiency. The potential to recover missing information on the tongue tip position from reverberation artifacts is assessed.

Can preoperative planning using IRIS™ three-dimensional anatomical virtual models predict operative findings during robot-assisted partial nephrectomy?

ObjectiveTo evaluate the predictive validity of IRIS™ (Intuitive Surgical®, Sunnyvale, CA, USA) as a planning tool for robot-assisted partial nephrectomy (RAPN) by assessing the degree of overlap with intraoperative execution. MethodsThirty-one patients scheduled for RAPN by four experienced urologists were enrolled in a prospective study. Prior to surgery, urologists reviewed the IRIS™ three-dimensional model on an iphone Operating System (iOS) app and completed a questionnaire outlining their surgical plan including surgical approach, and ischemia technique as well as confidence in executing this plan. Postoperatively, questionnaires assessing the procedural approach, clinical utility, efficiency, and effectiveness of IRIS™ were completed. The degree of overlap between the preoperative and intraoperative questionnaires and between the planned approach and actual execution of the procedure was analyzed. Questionnaires were answered on a 5-point Likert scale and scores of 4 or greater were considered positive. ResultsMean age was 65.1 years with a mean tumor size of 27.7 mm (interquartile range 17.5–44.0 mm). Hilar tumors consisted of 32.3%; 48.4% of patients had R.E.N.A.L. nephrometry scores of 7–9. On preoperative questionnaires, the surgeons reported that in 67.7% cases they were confident that they can perform the procedure successfully, and on intraoperative questionnaires, the surgeons reported that in 96.8% cases IRIS™ helped achieve good spatial sensation of the anatomy. There was a high degree of overlap between preoperative and intraoperative questionnaires for the surgical approach, interpreting anatomical details and clinical utility. When comparing plans for selective or off-clamp, the preoperative plan was executed in 90.0% of cases intraoperatively. ConclusionA high degree of overlap between the preoperative surgical approach and intraoperative RAPN execution was found using IRIS™. This is the first study to evaluate the predictive accuracy of IRIS™ during RAPN by comparing preoperative plan and intraoperative execution.

Tridimensional models and radiographic study of dorsal laminectomy and thoracolumbar hemilaminectomy in dogs.

To create three-dimensional anatomical models of the thoracic and lumbar portions of the canine spine that reproduce the vertebral surgical approaches of dorsal laminectomy and hemilaminectomy, and to perform the respective radiographic evaluations of each approach. In a digital archive of the canine spine, digitally replicate the dorsal laminectomy and hemilaminectomy in the thoracic and lumbar portions and, then, make tridimensional prints of the vertebral models and obtain radiographs in three dorsoventral, ventrodorsal and laterolateral projections. The anatomical models of the surgical spinal canal accesses of the thoracic and lumbar portions showed great fidelity to the natural bones. The created accesses have the proper shape, location and size, and their radiographic images showed similar radiodensities. The replicas of the dorsal laminectomy and hemilaminectomy developed in the anatomical models in the thoracic and lumbar portions are able to represent the technical recommendations of the specialized literature, as well as their respective radiographic images, which have certain radiological properties that allow to make a deep radiological study. Therefore, the models are useful for neurosurgical training.

Augmented Reality Technology Applied to Surgical Planning in Oncological Colorectal Surgery

This paper describes the application of augmented reality technology from three-dimensional colon models as a method of preoperative planning in oncological colorectal surgery. We have developed holograms of augmented reality from threedimensional anatomical models of the colon, obtained from computed tomography images (Siemens Somatom Perspective 64) with abdominal image cuts 3 mm thick. The recovery of the images was in DICOM format. The processing to achieve the threedimensional reconstruction was performed with the program OsiriX, which made a complete segmentation of the colon surface and modified the image density. 3D models were obtained of the isolated colon and in relationship with the bony structures. The smartphone Colon 3D AR application was designed (increased hyper experience- visualizer with SLAM technology) to apply augmented reality technology. An individualized hologram of augmented reality (scale 1:1) was created from each three-dimensional model. A projection with the smartphone on the patient's abdomen was made by modifying the position in the height of the reconstruction, using the pelvic bones as an anatomic reference point to calibrate the hologram's orientation. Three-dimensional reconstruction of the tumor in the preoperative plan of oncological colorectal surgery, combined with hyperreality technology, allows developing augmented reality models to improve colon anatomy knowledge and plan the surgical technique. The application is easy to use and may have advantages in preoperative colon surgery planning.

Generalizable multi-task, multi-domain deep segmentation of sparse pediatric imaging datasets via multi-scale contrastive regularization and multi-joint anatomical priors.

Clinical diagnosis of the pediatric musculoskeletal system relies on the analysis of medical imaging examinations. In the medical image processing pipeline, semantic segmentation using deep learning algorithms enables an automatic generation of patient-specific three-dimensional anatomical models which are crucial for morphological evaluation. However, the scarcity of pediatric imaging resources may result in reduced accuracy and generalization performance of individual deep segmentation models. In this study, we propose to design a novel multi-task, multi-domain learning framework in which a single segmentation network is optimized over the union of multiple datasets arising from distinct parts of the anatomy. Unlike previous approaches, we simultaneously consider multiple intensity domains and segmentation tasks to overcome the inherent scarcity of pediatric data while leveraging shared features between imaging datasets. To further improve generalization capabilities, we employ a transfer learning scheme from natural image classification, along with a multi-scale contrastive regularization aimed at promoting domain-specific clusters in the shared representations, and multi-joint anatomical priors to enforce anatomically consistent predictions. We evaluate our contributions for performing bone segmentation using three scarce and pediatric imaging datasets of the ankle, knee, and shoulder joints. Our results demonstrate that the proposed approach outperforms individual, transfer, and shared segmentation schemes in Dice metric with statistically sufficient margins. The proposed model brings new perspectives towards intelligent use of imaging resources and better management of pediatric musculoskeletal disorders.

Computer-aided Design of Distal Femoral Osteotomy for the Valgus Knee and Effect of Correction Angle on Joint Loading by Finite Element Analysis.

Lateral open-wedge distal femoral osteotomy (DFO) has been used to treat valgus deformity of the knee, with good clinical outcomes. However, there is a lack of biomechanical studies regarding the angle of correction. The objective of this study was to apply computer-aided design (CAD) for osteotomy planning in a three-dimensional (3D) anatomical model and to assess the biomechanical differences among the varying correction angles on joint loading by finite element analysis (FEA). To model different angles of lateral open-wedge DFO correction, the CAD software package Mimics 21.0 was used to accurately simulate the operated knee. The femur was cut to 0°, 2°, 4°, 6°, 8°, and 10° of varus (equivalent to hip-knee-ankle angles of 180°, 178°, 176°, 174°, 172°, and 170°, respectively). The original knee model and the corrected models were processed by FE software. Then, the FE models were subjected to an axial force to obtain the von Mises stress (VMS) and shear stress distributions within the femoral cartilages and menisci. Under a compressive load of 740 N, the highest VMS in lateral and medial compartments of the intact knee model was 3.418 and 3.303 MPa. The maximum value of both the VMS and the shear stress in the lateral compartment decreased as the varus angle increased, but the corresponding values in the medial compartment increased. When the hip-knee-ankle (HKA) angle was 180°, the VMS in the lateral and medial compartments was balanced (3.418 and 3.303MPa, respectively). Meanwhile, when the HKA angle was 178° (3.488 and 3.625MPa, respectively), the shear stress in the lateral and medial compartments was balanced. In addition, the magnitude of change in the stress was significantly higher in the medial compartment (90.9%) than in the lateral compartment (19.3%). The optimal correction angle of the valgus knee is close to neutral alignment or slightly varus (0° - 2°). Overcorrection is not recommended, as it can result in a steep increase of the stress within the medial compartment and may accelerate the process of medial compartment OA.

Application of Medical Imaging and 3D Printing Technology in Teaching the Handling of Novel Medicine in Periodontal Surgery.

Recently, fibroblast growth factor-2 (FGF-2) agents for periodontal tissue regeneration have been increasingly applied to the treatment of periodontal disease. Our current challenge for resident dentists with little clinical experience is to enhance instruction in the handling of new medicine in addition to teaching conventional procedures in periodontal tissue regeneration. This report describes using case-specific, cost-effective three-dimensional (3D) models for dentists' lectures and periodontal surgical training.As an educational and training aid, preoperative and postoperative cone-beam computed tomography images were superimposed to enable three-dimensional observation of postoperative bone regeneration. A three-dimensional anatomical model was fabricated based on these images. Dental laboratory materials were used to reproduce the periosteum and gum. The fabrication time per 3D model was about 2 hours and the cost per model was about $0.5. These models were used for lectures to resident dentists and periodontal surgery training, and their feedback was obtained. The resident's response to surgical training using these 3D models was generally positive.The use of FGF-2 represents a new direction in the treatment of periodontal disease. This being new, however, means that inexperienced periodontists require training in its application and how this will affect prognosis, as this will differ from that with more conventional techniques aimed at tissue regeneration. The low-cost 3D model presented in this report can be a valuable tool to help accomplish this in teaching inexperienced dentists, such as resident dentists.

Practical Application of Augmented/Mixed Reality Technologies in Surgery of Abdominal Cancer Patients.

The technology of augmented and mixed reality (AR/MR) is useful in various areas of modern surgery. We considered the use of augmented and mixed reality technologies as a method of preoperative planning and intraoperative navigation in abdominal cancer patients. Practical use of AM/MR raises a range questions, which demand suitable solutions. The difficulties and obstacles we encountered in the practical use of AR/MR are presented, along with the ways we chose to overcome them. The most demonstrative case is covered in detail. The three-dimensional anatomical model obtained from the CT scan needed to be rigidly attached to the patient’s body, and therefore an invasive approach was developed, using an orthopedic pin fixed to the pelvic bones. The pin is used both similarly to an X-ray contrast marker and as a marker for augmented reality. This solution made it possible, not only to visualize the anatomical structures of the patient and the border zone of the tumor, but also to change the position of the patient during the operation. In addition, a noninvasive (skin-based) marking method was developed that allows the application of mixed and augmented reality during operation. Both techniques were used (8 clinical cases) for preoperative planning and intraoperative navigation, which allowed surgeons to verify the radicality of the operation, to have visual control of all anatomical structures near the zone of interest, and to reduce the time of surgical intervention, thereby reducing the complication rate and improving the rehabilitation period.

How to Create and 3D Print a Model of the Skull and Orbit for Craniomaxillofacial Surgeons

Three-dimensional (3D) anatomical models are used in many ways in cranio-maxillo-facial (CMF) surgery, including being used to press-fit plates, mold splints, and for student teaching. Their use has many advantages, including the possibility of lowering operative time and allowing for more precise reconstructions with personalized plates, meshes, and splints. This can now be done in-house to speed up model availability for trauma surgery as well. Three-dimensional printers and software are quickly evolving—printers now are easily accessible, and the models are inexpensive to print. However, for a surgeon with no IT training, 3D printing even a simple anatomic model may be a challenge. The purpose of this article is to offer simple, step-by-step video tutorials demonstrating the process of extracting a CMF model from a patient CT scan, doing basic manipulation to the model, and then printing it in-house with a prosumer grade 3D printer. It is our hope that this user-friendly article will allow more surgeons and scientists to use 3D printing and its advantages.

The experience of using additive technologies for three-dimensional reconstruction of the lungs in the clinical practice of a tuberculosis dispensary

The aim was to study the volume of blood loss and the duration of a surgical session in patients with destructive pulmonary tuberculosis using threedimensional anatomical models of the lungs. Methods. The study was conducted in 2020 – 2021 in the State Budgetary Healthcare Institution of the Nizhniy Novgorod region “Nizhny Novgorod Regional Clinical Tuberculosis Dispensary” as part of an internal grant from the Federal State Budgetary Educational Institution of Higher Education “Privolzhsky Research Medical University” of the Ministry of Health of the Russian Federation. The prospective clinical study included 80 patients. All patients were divided into two groups. The main group included 40 patients. Preoperative lung reconstruction was performed for these patients. Thoracic surgeons used the three-dimensional anatomical models of the lungs to study the syntopy of healthy and diseased tissue (visual assessment) and prepare for the surgical session (cutting the model with a scalpel). Threedimensional preoperative lung reconstruction was not performed for the other 40 patients in the control group. In this group, the thoracic surgeons did not use 3D anatomical models of the lungs. Comparison of the results in the control and the main group was carried out using the Mann – Whitney U-test and Spearman and Kendall correlation tests. The obtained data are described with absolute and relative values, boxplots reflecting median (Me) and interquartile interval (IQI), scatter plots with trend lines, and probability density plots. The level of statistical significance of differences for testing the hypotheses was chosen at p &lt; 0.05. Results. It was shown that the volume of blood loss (U = 590; p = 0.042) and the duration of surgery (U = 587; p = 0.041) in patients of the main group are smaller than in patients in the control group. A moderate correlation was established between the volume of blood loss and the duration of the surgical session (ρ = 0.54; p &lt; 0.001) in the main group using the Spearman’s test. Kendall’s test also showed a positive correlation (τ = 0.42; p &lt; 0.001). Conclusion. The established differences between the main group and control group in the volume of blood loss and the duration of surgery due to the inclusion of polymer models of the lungs in preoperative preparation of thoracic surgeons confirm our hypothesis about the effect of additive technologies on the above parameters and indicate the significance of the applied reconstruction method.

Perspectives of online anatomy teachers: A neglected study population struggles with the invisible student.

Online teachers are an under-researched population, but their perspectives are crucial to the successful implementation of online education. A fully online section of an established face-to-face (F2F) two-semester undergraduate anatomy course with a prosection laboratory commenced in 2012 at The University of Western Ontario, Canada. Professors' lectures for F2F students were broadcast in live and archived format to online students using Blackboard Collaborate (BBC) video conferencing software. Teaching assistants (TAs) delivered online laboratories using BBC and three-dimensional (3D) anatomical computer models. This study explored the common experiences and issues faced by the course teachers from 2012 to 2014. Transcripts from open-ended, individual interviews with professors (n=4) and TAs (n=5) were coded and analyzed thematically. The teachers' concern for their inability to see the students during sessions to assess class engagement and their teaching effectiveness, and to develop social relationships, was the main finding. However, video conferencing software and email were sufficient communication methods for the students' questions and the teachers' answers. The TAs noted usability challenges and anatomical inaccuracies in the 3D models compared to cadavers. Due to limitations of BBC's screen sharing function, live manipulation for the 3D computer models was not possible; however, the TAs found pedagogical value in using screen captures of the models for drawing activities with the students. Overall, preparation time for teaching online was longer than for F2F. The study's findings provide science educators with issues to consider when preparing for online teaching and recommendations to optimize the teaching experience.

Is Proximal Tibia Sufficient for Accurate Measurement of Tibial Slope Angles on Three-dimensional Tomography-based Anatomical Models?

Tibial slope measurements performed using only the proximal part of tibia ignore the native tibial anatomical axis. Our first aim is to measure the native medial, lateral and total tibial slope angles of gender groups using the whole tibial anatomical axis on computerized tomography-based three-dimensional anatomical models. The second aim is to determine the correlation between proximal and whole tibial anatomical axis for measurement of medial, lateral, and total tibial slope angles. We randomly selected 100 females and 100 males between 18-60 years of age. Three-dimensional anatomical models of right and left tibia were created. The gender-specific differences of medial, lateral, and total tibial slope angles according to proximal and whole tibial anatomical axis were measured. Correlation coefficients (r) of medial, lateral, and total tibial slope angles measured with proximal and whole tibial anatomical axis were calculated. The mean age was 47.1 years. A statistically significant difference was observed between female (7.1 ± 3) and male (8.2 ± 2.5) groups in terms of mean lateral tibial slope angles according to the whole tibial anatomical axis (p=0.008). A strong correlation between proximal and whole tibial anatomical axis for all tibial slope angle measurements was detected. The method we determined for 3D measurement of medial, lateral and total tibial slope angles using proximal tibial anatomical axis has a strong correlation with slope angles measured in accordance with the whole tibial anatomical axis. Our 3D tibial slope angle measurement method on the proximal tibia has high reliability and could be used in the daily practice.

Abstract 9842: An Implemented Medical Mockup Modelling for Personalised Medicine and Surgery

Introduction: Virtual three-dimensional (3D) anatomical models can improve diagnostic and surgical medical procedures with a patient-specific approach. The advantage of these models, in opposition to CT scans or MRIs alone, is their unique ability to demonstrate anatomical spatial relationship with submillimetre accuracy. Methods: Starting from our platform Med3D VR Lab, we implemented, in the MMM project, a basic algorithm within a software, able to capture, from DICOM images (MRIs/CT scans), the cloud of points needed to build 3D images. Different areas of a tissue might have different radio-density levels. In these cases, we applied our patented algorithm to harmonize these values through a transformation matrix. Results: We created a VR Laboratory (via a supervised learned approach) to access the resulting 3D image. The user, by wearing a VR headset, can rotate and enlarge the heart’s model. By cutting the model with the scalpel tool, the user is able to see the interior of the 3D model. The sections of the heart are created according to the direction of the cut. Each section can be further cut into smaller sub-sections, and both sections and sub-sections can be saved for future use. Conclusions: We developed a software for the conversion of 2D cardiac images in 3D models, which can be further examined and sectioned in a VR environment. This technique could help cardiologists in refining diagnosis and surgeons in tailoring cardiac interventions on the basis of patients’ characteristics, thus reducing operating times and costs while also preventing possible complications in cardiac surgery- therefore allowing to precisely assess risks in advance. Moreover, our software, through the VR visor, allows patients to truly understand their clinical conditions, thus overcoming the drawbacks of expressing an informed consent based only on DICOM imaging: the patients themselves will be able to understand the risks and benefits of a given surgical operations or its alternatives.