Principal Considerations For The Contemporary High-Fidelity Endovascular Simulator Design Used In Training And Evaluation

Background The simulation and rehearsal of virtual endovascular procedures are anticipated to improve the outcomes of actual procedures. Contemporary, high-fidelity simulation is based on feedback systems that combine concepts of mechanical, electrical, computer, and control systems engineering to reproduce an interactive endovascular case. These sophisticated devices also include psychometric instruments for objective surgical skill assessment. The goal of this report is to identify the design characteristics of commercially available simulators for endovascular procedures and to provide a cross-section comparison across all devices to aid in the simulator selection process. Methods Data were obtained (1) by a standard questionnaire issued to four simulator companies prompting for relevant design details of each model for the expressed purpose of publication, (2) from each manufacturer\u27s respective website including appended sales brochures and specification sheets, and (3) by an evaluation of peer-reviewed literature. Focus topics include haptic technology, vessel segmentation, physiologic feedback, performance feedback, and physical logistics (ie, weight, dimensions, and portability). All data sources were surveyed between January 1, 2012, and June 30, 2013. Results All of the commercially available, high-fidelity endovascular simulators use interactive virtual environments with preprogrammed physics and physiology models for accurate reproduction of surgical reality. The principal differences between devices are the number of access sites and haptic devices, the ability to reconstruct patient-specific anatomy for preprocedural rehearsal, and the available peripheral training modalities. Hardware and software options can also vary within the same device in comparing patient-specific with generic cases. Conclusions Despite our limited knowledge about the potential of high-fidelity simulation within the endovascular world, today\u27s currently available simulators successfully provide high-fidelity reproductions of the endovascular environment. We have found that all of the commercially available devices incorporate the necessary features for a high-fidelity experience: (1) haptic technology, (2) vessel reconstruction, (3) physiology feedback, and (4) performance feedback. Significant variations in design do exist and may influence differences in skill development, evaluation, or cost. However, further validation of these differences is still needed and would benefit program directors interested in expanding these platforms for vascular training and certification as this technology matures. © 2014 by the Society for Vascular Surgery

Principal Considerations For The Contemporary High-Fidelity Endovascular Simulator Design Used In Training And Evaluation

Background The simulation and rehearsal of virtual endovascular procedures are anticipated to improve the outcomes of actual procedures. Contemporary, high-fidelity simulation is based on feedback systems that combine concepts of mechanical, electrical, computer, and control systems engineering to reproduce an interactive endovascular case. These sophisticated devices also include psychometric instruments for objective surgical skill assessment. The goal of this report is to identify the design characteristics of commercially available simulators for endovascular procedures and to provide a cross-section comparison across all devices to aid in the simulator selection process. Methods Data were obtained (1) by a standard questionnaire issued to four simulator companies prompting for relevant design details of each model for the expressed purpose of publication, (2) from each manufacturer\u27s respective website including appended sales brochures and specification sheets, and (3) by an evaluation of peer-reviewed literature. Focus topics include haptic technology, vessel segmentation, physiologic feedback, performance feedback, and physical logistics (ie, weight, dimensions, and portability). All data sources were surveyed between January 1, 2012, and June 30, 2013. Results All of the commercially available, high-fidelity endovascular simulators use interactive virtual environments with preprogrammed physics and physiology models for accurate reproduction of surgical reality. The principal differences between devices are the number of access sites and haptic devices, the ability to reconstruct patient-specific anatomy for preprocedural rehearsal, and the available peripheral training modalities. Hardware and software options can also vary within the same device in comparing patient-specific with generic cases. Conclusions Despite our limited knowledge about the potential of high-fidelity simulation within the endovascular world, today\u27s currently available simulators successfully provide high-fidelity reproductions of the endovascular environment. We have found that all of the commercially available devices incorporate the necessary features for a high-fidelity experience: (1) haptic technology, (2) vessel reconstruction, (3) physiology feedback, and (4) performance feedback. Significant variations in design do exist and may influence differences in skill development, evaluation, or cost. However, further validation of these differences is still needed and would benefit program directors interested in expanding these platforms for vascular training and certification as this technology matures. © 2014 by the Society for Vascular Surgery

Comparison Between Bench-Top And Computational Modelling Of Cerebral Thromboembolism In Ventricular Assist Device Circulation

Despite improvements in ventricular assist devices (VAD) design, VAD-induced stroke rates remain remarkably high at 14–47%. We previously employed computational fluid dynamics (CFD) to propose adjustment of VAD outflow graft (VAD-OG) implantation to reduce stoke. Herein, we present an in-vitro model of cerebral vessel embolization in VAD-assisted circulation, and compare benchtop results to CFD predictions. The benchtop flow-loop consists of a 3D printed aortic bed using Accura 60 polymer driven by a continuous-flow pump. Three hundred spherical particles simulating thrombi of 2, 3.5, and 5 mm diameters were injected at the mock VAD-OG inlet. A water and glycerin mixture (3.8 cP viscosity) synthetically mimicked blood. The flowrate was adjusted to match the CFD Reynolds number. Catch cans were used to capture and count particles reaching cerebral vessels. VAD-OG geometries were evaluated using comparison of means Z-score range of −1.96 ≤ Z ≤ 1.96 to demonstrate overall agreement between computational and in-vitro techniques. Z-scores were: (i) Z = −1.05 for perpendicular (0°), (ii) Z = 0.32 for intermediate (30°), and (iii) Z = −0.52 for shallow (60°) anastomosis and confirmed agreement for all geometries. This study confirmed added benefits of using a left carotid artery bypass-graft with percent embolization reduction: 22.6% for perpendicular, 21.2% for intermediate, and 11.9% for shallow anastomoses. The shallow anastomosis demonstrated lower degrees of aortic arch flow recirculation, consistent with steady-flow computations. Quantitatively and qualitatively, contemporary steady-flow computational models for predicting VAD-induced cerebral embolization can be achieved in-vitro to validate the CFD equivalent