TeleRobotic fundamentals of laparoscopic surgery (FLS): effects of time delay--pilot study

Within the area of telerobotic surgery no standardized means of surgically relevant performance evaluation has been established. The Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) Fundamentals of Laparoscopic Surgery (FLS) program provides a set of standardized tasks that are considered the 'gold standard' in surgical skill assessment. We present a methodology for using one of the SAGES FLS tasks for surgical robotic performance evaluation. The TeleRobotic FLS methodology is extendable to two other FLS tasks. Time delay in teleoperation in general and telesurgery in particular is one of the fundamental effects that limits performance in telerobotic surgery. In this pilot study the effect of time delay on the Block Transfer task performance was investigated. The RAVEN Surgical Robot was used in a master/slave configuration in which time delays of 0, 250, 500, and 1000 ms were introduced by a network emulator between the master (Surgeon Site) and the slave (Patient Site). The study included three subjects, each of whom was presented with three of the four conditions. The results show that one subject had a lower error rate with increasing time delay, whereas the other subjects had a higher error rate with increased delay. The subject with the longest average completion time suffered the least performance decrease under time delay.