Effects of modifying hinotori™ surgical robot system on perioperative outcome of robot-assisted radical prostatectomy

Objectives One of the main advantages of the hinotori (TM) surgical robot system (HSRS) is that it can be easily adjusted. This study aimed to clarify the effects of modifying the HSRS on the perioperative outcomes of robotic-assisted radical prostatectomy (RARP). Methods Overall, 158 cases of RARP using the HSRS were classified into three groups based on the modification to the system: group A (no modification, 70 cases), group B (addition of the ability to switch between two types of scopes and to adjust the arm base tilt back and forth, left and right, 42 cases), and group C (reduction of arm floating sensation, mitigation of emergency stop during arm collision, and addition of clutch function via hand switch in addition to foot pedal, 46 cases). The perioperative outcomes of each group were compared. Results The median of operation time, cockpit time, and cockpit time excluding the time required for lymph node dissection of group C were 223, 146, and 135 min, respectively, where are significantly shorter than those of group A (308, 228, and 208 min, p < 0.0001, respectively) and group B (319, 241, and 214 min, p < 0.0001, respectively). There was no significant difference in the rate of positive margin rates and the pad-free rate before the first follow-up visit among these three groups. The complication rates in groups A, B, and C were 11.4%, 9.4%, and 8.4% (Clavien-Dindo grades I-II), and 4.3%, 2.4%, and 0% (grade III), respectively. Conclusions The modifications to the HSRS have enabled smoother surgical procedures for RARP.