Transrectal laparoscopy using flexible endoscopy with a submucosal tunneling method: Porcine survival model

Transrectal laparoscopy (TRLS) using a flexible endoscope was recently proposed for peritoneal observation. Although previous studies have reported its feasibility, follow-up durations were insufficient to ascertain technical safety. Moreover, knowledge about the technical feasibility of collecting peritoneal cytological lavage or ascites during TRLS is limited. Thus, this study aimed to confirm the safety and efficacy of TRLS in a porcine survival model.

After creating artificial ascites in 10 animals, TRLS was performed as follows: submucosal tunnel creation on the anterior wall of the rectum, intentional perforation at the distal end of the tunnel, endoscopic ascites collection and intraperitoneal observation, and clip closure at the mucosal incision site. The pigs were administered antibiotics orally for 7 days after TRLS and killed for histological evaluation and bacterial culture after 28 days of observation.

The technical success rates of insertion into the abdominal cavity, ascites collection, and clip closure were 100%. All frequent anatomical sites for peritoneal dissemination including the stomach, subdiaphragmatic space, and pelvic space were fully observable without adverse events. The median procedure time was 36.3 min. Full 28-day survival was observed in all cases without any infection. The autopsies showed no infection, including abscess formation. Bacterial cultures of the peritoneal cavity were negative 28 days after TRLS in all cases.

Transrectal laparoscopy enabled ascites collection and intraperitoneal observation without adverse events. All animals survived without peritonitis. Therefore, TRLS can be an option for intraperitoneal examination.