Three-dimensional laparoscopic vision improves forceps motion more in the depth direction than in the horizontal...

Three-dimensional (3D) laparoscopic vision can improve depth perception. However, it is a question whether 3D vision can improve motion in the depth direction. The aim of this study was to compare the impact of 3D vision on forceps motion in the depth and horizontal directions.

All data were obtained from our previous two studies, where, in total, 40 novices and 20 moderately experienced surgeons participated. A simple phantom task was performed in a training box. The participants were randomly assigned to two groups. Specifically, one group performed the task five times initially under a two-dimensional (2D) system, and the other group started under a 3D system. Both groups then performed the same task five times under the alternative system. Performances were recorded by an optical position tracker. We separately evaluated forceps motion in the x-, y-, and z-axis directions.

Compared with the findings for 2D vision, the forceps path lengths were significantly decreased among novices and moderately experienced surgeons in almost all tasks under 3D vision. In a comparison of the path length ratio (3D/2D) in each direction, larger reduction was observed for the depth direction among novices, whereas no significant directional difference was noted among moderately experienced surgeons.

For novices, 3D laparoscopic vision improves depth perception and may give shorter forceps movement in the depth direction even for simple tasks.