The learning effect of using stereoscopic vision in the early phase of laparoscopic surgical training for novices

BACKGROUND: Recently to improve depth perception, the performance of three-dimensional (3D) laparoscopic surgeries has increased. However, the effects of laparoscopic training using 3D are still unclear. This study aimed to clarify the effects of using a 3D monitor among novices in the early phase of training. METHODS: Participants were 40 novices who had never performed laparoscopic surgery (20 medical students and 20 junior residents). Three laparoscopic phantom tasks (task 1: touching markers on a flat disk with a rod; task 2: straight rod transfer through a single loop; and task 3: curved rod transfer through two loops) in the training box were performed ten times, respectively. Performances were recorded by an optical position tracker. The participants were randomly divided into two groups: one group performed each task five times initially under a 2D system (2D start group), and the other group performed each task five times under a 3D system (3D start group). Both groups then performed the same task five times. After the trial, we evaluated the performance scores (operative time, path length of forceps, and technical errors) and the learning curves for both groups. RESULTS: Scores for all tasks performed under the 3D system were significantly better than scores for tasks using the 2D system. Scores for each task in the 2D start group improved after switching to the 3D system. However, scores for each task in the 3D start group were worse after switching to the 2D system, especially scores related to technical errors. CONCLUSIONS: The stereoscopic vision improved laparoscopic surgical techniques of novices from the early phase of training. However, the performance of novices trained only by 3D worsened by changing to the 2D environment.