title: Pure natural orifice transluminal endoscopic surgery (NOTES) with ultrasonography-guided transgastric access and over-the-scope-clip closure: a porcine feasibility and survival study.
abstract: BACKGROUND
  Most natural orifice transluminal endoscopic surgery (NOTES) procedures to date rely on the hybrid technique with simultaneous laparoscopic access to protect against access-related complications and to achieve adequate triangulation for dissection. This is done at the cost of the potential benefits of this new minimally invasive technique. This study aimed to evaluate the feasibility and safety of a transgastric (TG) pure-NOTES procedure in a diagnostic setting.
  
  
  METHODS
  A TG pure-NOTES procedure with endoscopic ultrasonograpy (EUS)-guided access and over-the-scope-clip (OTSC) closure was performed for 10 pigs in a survival and feasibility study. A full macroscopic necropsy with subsequent histologic evaluation was performed on postoperative day (POD) 14. The outcome parameters were uncomplicated follow-up assessment, survival, intraoperative complications, intraabdominal pathology, macroscopic full-thickness closure, and histology-proven full-thickness healing of the gastrotomy.
  
  
  RESULTS
  An uncomplicated postoperative course was reported for 9 of the 10 pigs, and survival was reported for all 10 pigs. For all the pigs, EUS-guided access was performed successfully with a median duration of 25 min (range, 12-62 min) and without intraoperative complications or access-related lesions at necropsy. An OTSC closure was achieved with a median duration of 11 min (range, 3-28 min). The OTSC provided immediate closure, but according to the authors' definition of a full-thickness healing evaluated by histologic examination, this was not achieved in any of the cases. Although all the animals survived until POD 14, intraabdominal chronic abscesses were present in 3 of the 10 pigs at necropsy.
  
  
  CONCLUSIONS
  The EUS-guided TG access proved to be feasible without access-related complications. Although OTSC provided an immediate closure, the histopathology raised concerns regarding the risk of perforation. Together with the high risk of intraabdominal infection, TG pure-NOTES is not yet ready for routine clinical practice.
authors.affiliation: Department of Surgical Gastroenterology, Herlev Hospital, University of Copenhagen, Herlev Ringvej 75, 2730 Herlev, Denmark. andersdonatsky@gmail.com
authors.forename: Anders Meller
authors.initials: AM
authors.lastname: Donatsky
authors.forename: Luise
authors.initials: L
authors.lastname: Andersen
authors.forename: Ole Lerberg
authors.initials: OL
authors.lastname: Nielsen
authors.forename: Barbara Juliane
authors.initials: BJ
authors.lastname: Holzknecht
authors.forename: Peter
authors.initials: P
authors.lastname: Vilmann
authors.forename: Søren
authors.initials: S
authors.lastname: Meisner
authors.forename: Lars Nannestad
authors.initials: LN
authors.lastname: Jørgensen
authors.forename: Jacob
authors.initials: J
authors.lastname: Rosenberg
mesh_terms: D000818:Animals; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D005773:Gastroscopy / Q000379:methods; D057605:Natural Orifice Endoscopic Surgery / Q000295:instrumentation / Q000379:methods*; D013525:Surgical Instruments; D016019:Survival Analysis; D034421:Sus scrofa; D018084:Ultrasonography, Interventional / Q000379:methods; D058106:Wound Closure Techniques / Q000295:instrumentation*