Journal of Surgical Simulation 2020; 7: 85 - 91

Published: 02 February 2021


Original article

Assessing round window depiction in a virtual reality environment for cochlear implantation

Justin T. Lui, Garrett D. Locketz, Joseph C. Dort, Joseph M. Chen, Justin K. Chau, Sonny K. Chan, Sumit K. Agrawal, J. Kenneth Salisbury and Nikolas H. Blevins
Corresponding author: Justin T. Lui, Department of Otolaryngology–Head & Neck Surgery, University of Toronto, 2075 Bayview Avenue, Room M1 102, Toronto, Ontario, M4N 3M5, Canada. Email:


Background: A recently developed patient-specific virtual reality (VR) simulator has previously shown value in surgical rehearsal, but not clinical utility. Adequate round window exposure during cochlear implantation dictates the route of electrode insertion, however, anatomic variability among patients exists. Using patient-specific specimens, this study assessed the VR platform’s ability to depict round window exposure during cochlear implantation surgery to evaluate its clinical utility.

Methods: Retrospective data from 21 patients who had undergone cochlear implantation surgery by a single surgeon were collected. Based on the operative notes and video, round window exposure was classified as grade I (≥50%) or grade II (<50%). Segmented preoperative clinical computed tomography datasets were loaded into a custom surgical rehearsal platform. Six experienced cochlear implantation otologists (including the operative surgeon) from four institutions performed virtual cochlear implantation surgery and graded round window exposure. These results were compared with the intraoperative findings.

Results: Overall, VR grading was congruent with the intraoperative gold standard in 78.6% (95% confidence interval, 73.3%–83.8%) of cases. Surgeons were more likely to correctly identify grade I (86.9%) than grade II (61.9%) exposures. The primary surgeon identified all five cases requiring a cochleostomy in comparison with the secondary surgeons, who correctly identified 48.0% (95% confidence interval, 14.7%–81.3%) of the cases.

Conclusion: Surgically relevant temporal bone anatomic variations can be accurately identified with VR rehearsal. Accuracy may depend on individual surgical technique, because one surgeon’s intraoperative findings may not be replicated by another’s rehearsal. Further prospective assessments will help establish the utility of VR rehearsal in cochlear implantation preparation.


virtual reality simulation; otology; temporal bone surgery; case-specific rehearsal; surgical rehearsal; surgical training;

Additional Information

Presented as a poster at the American Otologic Society meeting at the Combined Otolaryngologic Spring Meeting, April 1822, 2018, in National Harbor, MD, USA.