Effect of virtual reality on spatial-anatomical understanding in preoperative liver surgery: a randomized crossover study.

Precise spatial understanding of complex anatomy is critical for preoperative planning in hepatobiliary surgery. Traditional CT and MRI imaging require mental reconstruction of anatomy from 2D slices, imposing substantial cognitive load. Although 3D reconstructions improve spatial understanding, they are typically displayed on 2D screens, limiting true depth perception. Virtual Reality (VR) visualization offers both stereoscopic depth and embodied interaction to improve spatial-anatomical understanding, yet its quantitative advantage over standard desktop visualization remains uncertain, especially regarding task complexity. In this randomized crossover study, 58 medical students analyzed 3D liver models of varying complexity using both VR and desktop visualization. Performance on lesion/vessel relations and lesion segment allocation tasks served as a measure of spatial-anatomical understanding, while visuospatial ability was assessed with the Mental Rotations Test. In complex models, VR significantly improved performance compared with desktop visualization (28.0 ± 3.3 vs. 26.4 ± 3.6; p = 0.002, d = 0.46), whereas results for simpler models were comparable. The VR advantage scaled with task complexity and correlated with higher visuospatial ability (r = 0.31, p = 0.018). These findings indicate that VR is associated with measurable advantages under higher task complexity, supporting its potential role in surgical education and preoperative planning, although the present design cannot isolate which immersive features drive this benefit.