Virtual reality training improves wet-lab performance of capsulorhexis: results of a randomized, controlled study

Abstract

To investigate, whether capsulorhexis training on the EYESi surgical simulator improves wet-lab operating performance of surgical novices. Randomized, masked experimental study. Thirty-one medical students and 32 ophthalmological residents were randomized to either virtual reality (VR) training, or control. Initially and after 3 weeks each participant performed three capsulorhexis tasks in a porcine wet-lab. In between, participants from the VR training groups completed two training trials on the EYESi surgical simulator (VRmagic, Mannheim, Germany). VR training consisted of basic skill tasks and capsulorhexis tasks of increasing difficulty, and preset performance goals had to be reached for each task. All wet-lab procedures (n = 372) were recorded on DVD, and assessed by a masked observer. Each wet-lab capsulorhexis was evaluated with regard to five criteria (circularity, size, centering, time, tissue protection) using a predefined scoring system with a maximum overall score of 10 points (2 per criterion). The primary outcome measure was the intra-individual difference in the average overall performance score between the first and second wet-lab capsulorhexis procedures. Ten operation videos were additionally assessed by three further investigators to determine interobserver agreement. Inter-observer agreement regarding the overall performance score was high (ICC = 0.91). Compared to control groups, VR-trained students and residents showed significant improvement in their median wet-lab capsulorhexis overall performance score compared to controls (+3.67 vs +0.33 points, P = 0.001 and +3.33 vs +/-0.00 points, P < 0.0001). The capsulorhexis performance of VR-trained students and residents was also more consistent with a lower standard deviation of scores compared to controls (SD 1.3 vs 2.1 and 1.2 vs 1.7 points respectively). Structured capsulorhexis training on the EYESi to reach specific target criteria significantly improved wet-lab capsulorhexis performance.