Virtual Reality versus Screen-Based 3D Anatomy Applications for Teaching Lower Gastrointestinal Anatomy: A Pilot Randomized Controlled Trial (Preprint)

<sec> <title>BACKGROUND</title> <p>Undergraduate anatomy teaching has faced sustained pressure from reduced curricular time, diminished access to cadaveric dissection, and variable teaching quality. The lower gastrointestinal tract (GI), with its complex three-dimensional (3D) relationships between the small and large bowel, mesentery, and vasculature, is particularly difficult to teach using conventional two-dimensional (2D) resources. Immersive virtual reality (VR) offers stereoscopic visualization that may better support spatial understanding, but high-quality comparative trials evaluating VR against other digital (non-VR) platforms for lower GI anatomy remain scarce.</p> </sec> <sec> <title>OBJECTIVE</title> <p>To compare the effects of an immersive VR platform (3D Organon) with a non-immersive, screen-based 3D anatomy platform (Human BioDigital) on medical students' knowledge, confidence, and spatial understanding of lower GI anatomy.</p> </sec> <sec> <title>METHODS</title> <p>This prospective, multicenter pilot randomized controlled trial was conducted across four workshops at the Universities of Bristol and Exeter, following CONSORT e-Health guidelines. Medical students were randomized to VR (via PICO 4 Ultra headsets) or non-VR (via laptop), with both groups completing an identical structured task list of lower GI anatomical structures over a 20-minute session; participants subsequently crossed over to the alternate modality. Knowledge was assessed via a 10-item multiple-choice question test; confidence, spatial understanding, presence, and usability were assessed via pre- and post-session Likert-scale questionnaires. Within-group changes were analyzed using Wilcoxon signed-rank tests, and between-group differences using Mann–Whitney U tests.</p> </sec> <sec> <title>RESULTS</title> <p>Forty-three participants were analyzed (VR = 26, non-VR = 17). The VR group showed significant within-group improvements in MCQ score (change = 1.48 ± 1.887; P=0.003) and confidence in lower GI anatomy (change = 1.00 ± 1.020; P=0.001), while the non-VR group did not (MCQ P=0.091; confidence P=0.444); however, between-group differences in these changes were not statistically significant (MCQ P=0.607; confidence P=0.139). In contrast, VR was rated significantly higher than non-VR across all measures of spatial understanding and immersion, including depth perception (3.88 ± 0.993 vs 2.71 ± 1.047; P=0.001) and sense of presence (4.08 ± 1.017 vs 2.47 ± 1.281; P=0.001). When asked to choose directly, participants overwhelmingly preferred VR for spatial relationships (91%), enjoyment (91%), and future preference (79%), with non-VR favored only for ease of use by a minority (28%).</p> </sec> <sec> <title>CONCLUSIONS</title> <p>VR produced significant short-term gains in knowledge and confidence not observed with a non-VR digital platform, though between-group differences did not reach significance. VR demonstrated a clear, consistent advantage in spatial understanding and immersion. These findings support VR as a promising adjunct to conventional lower GI anatomy teaching, warranting larger, longer-term trials incorporating objective measures of presence and cognitive load.</p> </sec>