Optimal position of working ports in laparoscopic surgery: an in vitro study.

We investigated the optimal position of the laparoscope in relationship to the working ports. The optical angle (theta), defined as the angle formed by the line of action (determined by the working ports) and the line of vision (determined by the laparoscope), was varied by 30 degrees intervals from 0 degree to 180 degrees to the left and to the right. We also studied the time taken to accomplish a standardized task of tying a square knot with each optical angle in a laparoscopic simulator setting. The optimal position is at the optical angle of 0 degree. The optimal range of the optical angle is 60 degrees to the left and 60 degrees to the right of the optimal position of 0 degree.