The importance of stereoscopic vision in virtual surgical planning

Rendering software provides opportunities to display 3D images on a 2D display for the purposes of pre-operative planning, though with inherent size and depth ambiguity. The addition of stereoscopy as provided by modern virtual reality (VR) devices to traditional rendering principles may provide a more accurate conveyance of 3D patient anatomy. However, the added benefit of stereoscopic vision to pre-operative virtual planning has not been rigorously studied. A small pilot study was conducted to evaluate the following question: among a cohort of pediatric oncologic surgeons, how does stereoscopic vision resolve size-distance ambiguity during 3D virtual modeling using a commercially available virtual reality VR headset? The findings and interpretation of the results are discussed here to promote awareness of the issue of ambiguity in virtual modeling in light of the increasing popularity of virtual reality devices. In summary, surgeons viewing virtual 3D models are often not aware of the inherent ambiguity in the scene. Stereoscopic vision as provided by commercially available VR headset helps resolve ambiguity inherent to virtual scenes containing structures of unknown size and location. Transparent rendering, a mainstay of virtual pre-operative planning, is an ideal use case for stereoscopic vision. The use of stereoscopic displays for 3D surgical planning may reduce unanticipated intra-operative findings.