title: Pure NOTES rectosigmoid resection: transgastric endoscopic IMA dissection and transanal rectal mobilization in animal models.
abstract: BACKGROUND
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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).
  
  
  CONCLUSIONS
  A pure NOTES approach to rectosigmoid resection using transgastric endoscopic IMA dissection is technically feasible in animal models.
authors.affiliation: Department of Surgery, School of Medicine, Kyung Hee University, Seoul, Korea.
authors.forename: Sun Jin
authors.initials: SJ
authors.lastname: Park
authors.forename: Kil Yeon
authors.initials: KY
authors.lastname: Lee
authors.forename: Sung Il
authors.initials: SI
authors.lastname: Choi
authors.forename: Byung Mo
authors.initials: BM
authors.lastname: Kang
authors.forename: Chang
authors.initials: C
authors.lastname: Huh
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Choi
authors.forename: Chang Kyun
authors.initials: CK
authors.lastname: Lee
mesh_terms: D000714:Anastomosis, Surgical; D000818:Animals; D012809:Colon, Sigmoid / Q000601:surgery*; D004210:Dissection; D004285:Dogs; D005240:Feasibility Studies; D005774:Gastrostomy; D017537:Mesenteric Artery, Inferior / Q000601:surgery*; D023421:Models, Animal; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D012007:Rectum / Q000601:surgery*; D017792:Surgical Stapling; D013552:Swine