title: Transrectal peritoneal access with the submucosal tunnel technique in NOTES: a porcine survival study.
abstract: BACKGROUND
  Natural orifice transluminal endoscopic surgery (NOTES) procedures have been performed via transgastric, transvaginal, or transcolonic approaches. However, the transcolonic approach has potential disadvantages including intraperitoneal infection. To avoid such disadvantages, we applied the submucosal tunnel technique to transrectal peritoneal access in this study. Study aims are to clarify the technical feasibility of a submucosal tunnel method for transrectal abdominal access and to assess the healing process of the submucosal tunnel histopathologically.
  
  
  METHODS
  The study comprised six female pigs. The following procedures were performed: (1) The mucosa was cut after injection of sodium hyaluronate into the submucosa at the upper rectum. (2) Submucosal tunneling was performed by endoscopic submucosal dissection technique. (3) A small incision was made at the end of the tunnel. (4) After transrectal peritoneoscopy, the mucosal incision site was closed with endoclips.
  
  
  RESULTS
  Transrectal peritoneoscopy was successfully performed in all pigs. Necropsy revealed no findings of peritonitis. Histopathologic examination showed good healing of the submucosal tunnel. The wound healing process of the submucosal tunnel on postoperative day 7 was mainly in the inflammatory phase at the mucosal incision site, the proliferative phase at the submucosal tract, and the proliferative/remodeling phase at the seromuscular incision site.
  
  
  CONCLUSIONS
  The submucosal tunnel technique appears to be useful and safe for transrectal peritoneal access because healing at the seromuscular incision site proceeded rapidly.
authors: Department of Gastroenterological Surgery, Oita University Faculty of Medicine, Yufu, Oita, Japan. k-yohei@oita-u.ac.jp
authors: Yohei
authors: Y
authors: Kono
authors: Kazuhiro
authors: K
authors: Yasuda
authors: Kazuaki
authors: K
authors: Hiroishi
authors: Tomonori
authors: T
authors: Akagi
authors: Koji
authors: K
authors: Kawaguchi
authors: Kosuke
authors: K
authors: Suzuki
authors: Fumitaka
authors: F
authors: Yoshizumi
authors: Masafumi
authors: M
authors: Inomata
authors: Norio
authors: N
authors: Shiraishi
authors: Seigo
authors: S
authors: Kitano
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D005260:Female; D007413:Intestinal Mucosa / Q000473:pathology / Q000601:surgery*; D010535:Laparoscopy / Q000379:methods*; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D061646:Operative Time; D011349:Proctitis / Q000473:pathology; D012007:Rectum / Q000601:surgery*; D034421:Sus scrofa; D014945:Wound Healing / Q000502:physiology*