Pure NOTES rectosigmoid resection: transgastric endoscopic IMA dissection and transanal rectal mobilization in animal...

We report a pure natural orifice translumenal endoscopic surgery (NOTES(®); American Society for Gastrointestinal Endoscopy [Oak Brook, IL] and the Society of American Gastrointestinal and Endoscopic Surgeons [Los Angeles, CA]) rectosigmoidectomy in animal models using transgastric endoscopic inferior mesenteric artery (IMA) dissection and transanal rectal mobilization.

Ten live animals (2 pigs weighing 35-40 kg each and 8 dogs weighing 25-30 kg each) were used. A gastrotomy was made using a needle-knife puncture and the balloon dilatation technique or following the creation of a submucosal tunnel. A circular stapler shaft was transanally inserted up to the sigmoid colon for spatial orientation and traction of the mesocolon. The IMA was endoscopically dissected using a Coagrasper™ (Olympus, Tokyo, Japan) and then clipped. Endoscopic division of the sigmoid mesocolon was conducted laterally toward the marginal artery. Transanal full-thickness circumferential rectal and mesorectal dissections were performed, and a colorectal anastomosis was performed using a circular stapler with a single stapling technique. During the transanal approach, the gastrotomy was closed using four endoscopic clips.

Endoscopic dissection of the IMA was successful in all cases, but minor bleedings occurred in 3 cases. The mean time from dissection and clipping to division of the IMA was 36.7 minutes (range, 25-45 minutes). The mean operation time was 180.5 minutes (range, 145-210 minutes). There were no intraoperative complications or hemodynamic instability. The mean length of the resected specimen was 11.2 cm (range, 9-17 cm).

A pure NOTES approach to rectosigmoid resection using transgastric endoscopic IMA dissection is technically feasible in animal models.