Virtual Reality + Haptic Simulation for Retropubic Midurethral Slings (SlingVR)

Objectives: Existing training for ‘blind’ surgical procedures where surgeons rely on haptic rather than visual feedback to operate currently use expensive cadaver models, low fidelity physical models, or in an apprenticeship with live patients. A virtual reality simulator trainer with real patient-derived 3D anatomy and haptic feedback was created as a cost-effective solution for training blind operations. This study evaluated the retropubic midurethral sling prototype (SlingVR) for usability and perceived effectiveness.

Methods: A multi-disciplinary team of surgeons, engineers, motor control scientists, human factors experts, and virtual reality programmers created a Technology Readiness Level (TRL) 5 prototype of the SlingVR simulator. Expert surgeons and novices (medical students) performed surgical tasks and completed user interviews and usability evaluation surveys.
A cognitive task analysis using a think aloud protocol was used to understand how training design characteristics impacted learning and fidelity of the SlingVR system. Additional feedback was provided with semi-structured qualitative interviews after using the tool. Qualitative comments and investigator observations during the sessions were reviewed and summarized into themes. Students completed an evaluation and usability survey.

Results: 14 expert surgeons completed training and provided feedback for the first phase of the study. 6 themes were identified 1) Cognitive tasks, instruction, knowledge improvement, 2) System Feedback amount and type (ex. Continuous vs. intermittent, audio vs. visual) 3) Scoring/Competency 4) Immersion/ Realism 5) Design elements/Aesthetics 6) Gestalt/Impression. Themes were then used to make improvement to the training system.
17 fourth year medical students participated in the second phase of the study.
Students rated the SlingVR fidelity moderately high (mean = 4.06± 0.62, 8 items, coefficient alpha = 0.87) with a range of 2.67 to 4.89 out of 5 (Table 1 and 2). The visual realism of the pelvic model was rated highest (Mean = 4.33±0.77). Respondents reported the sling trocar felt and appeared realistic (72% agreed). While rated lowest, the majority (53%) agreed that the pelvic model haptics were realistic and 82% agreed that the system increased their confidence in performing the procedure. The training was rated highly effective (mean = 4.44± 0.54, 11 items, ). Respondents also reported high Usability of SlingVR (mean = 4.49± 0.49, 10 items, coefficient alpha = 0.87) Overall, the system was rated highly aesthetically pleasing, useful and easy to use for training.

Conclusions: We are innovating the way blind surgeries are taught, using virtual reality and haptics we have created a system to avoid practicing on patients or using cadaver models. Expert feedback was used to iterate the platform and trial with novices who found the training to be high fidelity, realistic, comfortable, easy to use, clear, and effective. This feedback will be used for improvement and generation of the next version.