Introduction: The antibacterial and healing properties of the greater omentum have yet to be used in translumenal access closure of NOTES procedures. Objective: To evaluate the feasibility, efficacy and tolerance of the incorporation of a flap of greater omentum in gastrotomy closure sites. Methods and procedures: Survival experiments were performed in nine 40-kg pigs under general anesthesia, sterile set-up and CO2 pneumoperitoneum. Animals were randomly assigned to 3 groups: Group A (controls, 3 pigs): 1.3 cm2 endoscopic full-thickness resection (EFTR) using an EMR kit (K-003, Olympus® Endo-Therapy, Olympus® America Inc., NY) to create transgastric access to the peritoneal cavity; peritoneoscopy; no closure. Group B (3 pigs): ETFR opening; peritoneoscopy; omentoplasty closure (flap of omentum gently pulled into stomach and attached to gastric mucosa with clips; no clip used for closure of the gastrotomy site itself). Group C (3 pigs): needle knife transmural puncture followed by balloon dilation for opening, transgastric peritoneoscopy, omentoplasty closure. Animals were survived for 2 weeks and then underwent endoscopic evaluation, necropsy and histological evaluation. Results: Transgastric access into the peritoneal cavity and peritoneoscopy were achieved in all pigs. In groups B and C, a flap of omentum was easily placed to seal the gastrotomy and then attached to the gastric mucosa using 2 to 5 clips (median=4), in 7 to 20 min (median=15). In group A, all animals developed peritonitis. In both groups B and C, all animals survived 15 days with good clinical outcome, no peritonitis and minimal adhesions outside the gastrotomy site (modified More Comprehensive Adhesion Scoring Method, ranging 1 to 12, median 3). In group B, 2 animals achieved complete healing of the gastrotomy site with no complication; 1 had an 18mm abscess in the omental flap and a 2mm mucosal ulceration. In group C, 2 animals achieved complete healing of the gastrotomy; 1 had a 2mm mucosal ulceration. Conclusions: Omentoplasty of gastrotomy site is a feasible and effective method to seal NOTES transgastric access to the peritoneal cavity. It is safe and reliable for the closure of conventional NOTES transgastric access (balloon dilation techniques). However, it may require additional methods when used in the setting of more aggressive transgastric access (EFTR).
Program Number: P215