Visual Displays and Visual Perception in Minimal Access Surgery

Visual perceptual processing underlies safe execution of endoscopic surgery. This review deals with the limitations of the present visual display technology used in endoscopic surgery with reference to the normal direct stereoscopic vision and points to the research and development needed in this important technological and psychomotor aspect of endoscopic surgery. Eyeball movements (saccadic and smooth pursuit), visual cues (stereoscopic and monoscopic), accommodation, individual visual attributes, and the display technology itself are all important. Monocular depth cues are degraded by the current display systems, and technological advances in this area will improve perceptual processing and reduce both fatigue and human error during endoscopic interventions. Depth perception can be improved by alternative techniques to three-dimensional imaging such as the VISTRAL system and the Suspended Image System based on projection of image by parabolic mirrors and advanced beam splitter technology.