Flexible versus rigid single-port peritoneoscopy: a randomized controlled trial in a live porcine model followed by initial experience in human cadavers.

INTRODUCTION: We compared single incision laparoscopic surgery with flexible endoscope ("flexible SILS") and with rigid optic ("rigid SILS") for access to 11 elective sites of peritoneal carcinomatosis.
MATERIALS AND METHODS: Back-to-back flexible and rigid SILS peritoneoscopy were performed in ten live pigs. SILS peritoneoscopy was performed using a flexible endoscope or a rigid optic, in random order, together with two rigid 5-mm laparoscopic forceps. Primary endpoint was access success rate to 11 elective sites of peritoneal carcinomatosis. Findings for the most favorable option were then assessed in four human cadavers.
RESULTS: In the porcine model, the overall rate of access to targets was 98% with flexible SILS and 87% with rigid SILS (p < 0.001). Both flexible and rigid SILS allowed a 100% access rate to diaphragmatic domes, paracolic gutters, splenic and hepatic hilum, pelvic floor, and trigonal bladder. The rates of access to other sites by flexible versus rigid SILS, respectively, were: root of the mesentery (90 vs. 50%), origin of the inferior mesenteric vein (90 vs. 50%), inferior vena cava (100 vs. 90%), and cul-de-sac of Douglas (100 vs. 50%). No complications were observed. Procedures were performed in mean time of 26 and 24 min, respectively. These findings were confirmed for flexible SILS in four human cadavers.
CONCLUSIONS: Flexible SILS is superior to rigid SILS to evaluate the peritoneal cavity in a timely manner. This suggests a need for flexible instrumentation or other technical solutions to perform thorough minimally invasive surgical evaluation of peritoneal carcinomatosis.