UCLA

Minimally invasive surgery (MIS) provides profound and well-known benefits to patients at the cost of increased technical difficulty for surgeons. In all types of minimally invasive surgery, including robotic, laparoscopic, and remote surgery, tactile information is altered, or in the case of robotic procedures, completely absent.

The first version of a tactile feedback system for robotic surgery was completed in 2008. During the course of this research, the feedback system was iteratively redesigned in order to address some of its shortcomings, improve its performance, and to allow the necessary expansion to other applications and in-vivo use.

When the improved tactile feedback system was integrated with a non-robotic laparoscopic grasper, it was found that tactile feedback significantly decreased the grip force of novice subjects during laparoscopic training, but had little impact on experts.

After designing a new water insulation methodology, the system was integrated with the da Vinci surgical robot and used for the first time in a live tissue experiment. This experiment showed that there was a high variability between subjects, and that there was a correlation between the amount of force used and amount of damage observed. Most expert and novice subjects used significantly decreased grasping forces, and had significantly fewer sites of damage when evaluated by a blinded pathologist, but some of this may have been caused by familiarization with the task.

The first prototype remote surgery system with tactile feedback was developed by combining three existing systems: The University of Washington RAVEN-II, the UCLA LapaRobot, and the improved tactile feedback system. In a preliminary investigation of remote surgery over a simulated network with delays of 100 ms and then 1 ms, there were decreases in grasping force for most subjects, and more significant retention when the time delay was minimized.

Together these findings suggest that tactile may be a beneficial addition to minimally invasive surgical systems - especially for cases with heavy cognitive demand, such as training of novice users, challenging control schemes, and when handling delicate tissue - and that efforts should continue to advance the feedback system towards clinical viability.