Preliminary Face Validation of a Virtual Translumenal Endoscopic Surgery Trainer (VTEST)

Woojin Ahn, PhD, Saurabh Dargar, Tansel Halic, PhD, Ganesh Sankaranarayanan, PhD, Kurt Roberts, MD, Suvranu De, ScD. Rensselaer Polytechnic Institute, Troy; University of Central Arkansas, Conway; Yale University, New Haven.

INTRODUCTION
The first virtual reality simulator for the Natural Orifice Translumenal Endoscopic Surgery (NOTES), VTEST^TM was developed to train surgeons in the hybrid transvaginal NOTES cholecystectomy procedure in Figure 1. A preliminary evaluation study was performed to assess the face validity of the VTEST^TM.

METHODS AND PROCEDURES
In this Institutional Review Board (IRB) approved study, a total of thirteen subjects with varying NOTES experience (ten NOTES and three GI surgeons) participated in the study at the 2013 Natural Orifice Surgery Consortium for Assessment and Research (NOSCAR) summit. The subjects were asked to perform the hybrid transvaginal NOTES cholecystectomy procedure on VTEST^TM that included the four tasks shown in Figure 2, and then were asked to answer a 5-point Likert scale feedback questionnaire consisting of fourteen questions: (1) realism of the anatomy, (2) realism in identification of the Calot’s triangle, (3) realism of the appearance of the simulator interface, (4) realism of the instrument handling, (5) overall realism of the blunt dissection task, (6) overall realism of the gall bladder removal task, (7) overall realism compared to the traditional laparoscopic tasks, (8) quality of the force feedback, (9) usefulness of the force feedback in performing the tasks (10) usefulness in learning hand-eye coordination (11) usefulness in learning ambidexterity skills, (12) overall usefulness in learning the fundamental NOTES skills (13) trustworthiness of the simulator in quantifying accurate measures of performance (14) trustworthiness of the simulator in providing different hand-eye coordination compared to traditional two-port laparoscopic approach.

RESULTS
The results from the face validity questionnaire are given in Table 1. Overall subjects rated ten of the questions above 3 or greater (60%) which includes the realism of the anatomical features, interface, and the tasks. Subjects also rated highly of trusting this simulator for measurement of performance. Results show that further improvement in blunt dissection and gall bladder removal tasks and the quality of force feedback is required.

CONCLUSIONS
The face validity of the first virtual reality NOTES simulator VTEST^TM was established. The result from this preliminary study shows that the simulator established validity on many aspects of the simulation and further refinement are currently taking place to improve the VTEST^TM simulator based on feedback.