Development of a compact laparoscope manipulator (P-arm).

BACKGROUND: Laparoscope manipulating robots are useful for maintaining a stable view during a laparoscopic operation and as a substitute for the surgeon who controls the laparoscope. However, there are several problems to be solved. A large apparatus sometimes interferes with the surgeon. The setting and repositioning is awkward. Furthermore, the initial and maintenance costs are expensive. This study was designed to develop a new laparoscope manipulating robot to overcome those problems. METHODS: We developed a compact robot applicable for various types of laparoscopic surgery with less expensive materials. The robot was evaluated by performing an in vitro laparoscopic cholecystectomy using extracted swine organs. Then, the availability of the robot to various operations was validated by performing a laparoscopic cholecystectomy, anterior resection of the rectum, and distal gastrectomy using a living swine. The reliability of the system was tested by long-time continuous running. RESULTS: A compact and lightweight laparoscope manipulating robot by the name of P-arm was developed. The surgical time of an in vitro laparoscopic cholecystectomy with and without the P-arm was not different. The three types of operations were accomplished successfully. During the entire procedure, the P-arm worked without trouble and did not interfere with the surgeons. Continuous 8-h operating tests were performed three times and neither discontinuance nor trouble occurred with the system. CONCLUSIONS: The P-arm worked steadily for various swine operations, without interfering with surgeon's work.