title: Endoscopic pyloromyotomy: a new concept of minimally invasive surgery for pyloric stenosis.
abstract: OBJECTIVE
  Pyloric stenosis is currently managed using open or laparoscopic pyloromyotomy. However, with recent improvements in flexible endoscopic instrumentation and techniques, totally peroral endoscopic approaches could reduce the invasiveness of myotomic procedures. The aim of the study was to establish the feasibility and efficacy of endoscopic submucosal pyloromyotomy in a porcine model.
  
  
  METHODS
  Four pigs were included in a preliminary study and a 2-week survival study was performed in another four pigs. An esophagogastroduodenoscope was inserted perorally into the stomach. Saline solution was injected into the submucosal space proximal to the pylorus. The gastric mucosa was incised and a 5-cm submucosal tunnel was created. After exposure of the muscular layer in a submucosal tunnel, myotomy of the circular muscle layer was performed until the longitudinal muscular layer was reached. Once myotomy was completed, endoscopic clips were used to re-approximate the mucosal incision.
  
  
  RESULTS
  Submucosal dissection, identification of the circular muscular layer, and pyloromyotomy were achieved in all animals. Acute complications such as bleeding and perforation were not observed in any cases. Median pyloric resting pressure was reduced from 16.5 mmHg to 6.1 mmHg immediately after myotomy and 8.4 mmHg at 14 days after myotomy.
  
  
  CONCLUSIONS
  Peroral endoscopic submucosal pyloromyotomy appears to be technically feasible and effective. Potential clinical applications, such as for infantile hypertrophic pyloric stenosis or delayed gastric emptying after esophagectomy, could be considered after confirmation of safety in additional survival studies.
authors.affiliation: Department of Surgery, IRCAD/EITS, Strasbourg, France. sur080@poh.osaka-med.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Kawai
authors.forename: S
authors.initials: S
authors.lastname: Peretta
authors.forename: O
authors.initials: O
authors.lastname: Burckhardt
authors.forename: B
authors.initials: B
authors.lastname: Dallemagne
authors.forename: J
authors.initials: J
authors.lastname: Marescaux
authors.forename: N
authors.initials: N
authors.lastname: Tanigawa
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005240:Feasibility Studies; D005753:Gastric Mucosa / Q000601:surgery; D005773:Gastroscopy / Q000379:methods*; D008365:Manometry; D057605:Natural Orifice Endoscopic Surgery / Q000379:methods*; D011707:Pyloric Stenosis / Q000601:surgery*; D011708:Pylorus / Q000473:pathology / Q000601:surgery*; D013552:Swine; D016896:Treatment Outcome