title: Selective fluid cushion in the submucosal layer by water jet: advantage for endoscopic mucosal resection.
abstract: OBJECTIVE
  Numerous new techniques have recently been reported and described for the endoscopic mucosal resection of large superficial lesions of the gastrointestinal tract. We present here for the first time the application of a water jet dissector for mucosa elevation.
  
  
  METHODS
  In an ex vivo study, the effectiveness of a water jet dissector (Helix Hydro-Jet) placed directly on the stomach walls of 8 pigs was examined to create a mucosal elevation. After having determined optimal pressures, angle of application, and application times, 13 submucosal fluid cushions were produced in different areas of the stomach walls of 8 pigs in vivo, and the sizes of the resulting submucosal cushions were measured.
  
  
  RESULTS
  Using pressures between 30 and 70 bar, it was routinely possible to create submucosal fluid cushions in the stomach wall ex vivo as well as in vivo. Histological examination showed a selective edema in the submucosa without damage to the deeper mucosal layers of the gastric wall.
  
  
  CONCLUSIONS
  The capacity of a targeted high-pressure water jet to penetrate the mucosa and selectively create a fluid cushion in the submucosa facilitates endoscopic resection of the mucosa. This new method could contribute to ameliorate the endoscopic treatment of mucosal tumors which previously could not be resected endoscopically due to their size, extent, or location.
authors.affiliation: Department of Surgery, University Hospital Mannheim, Ruprecht-Karls University Heidelberg, Mannheim, Germany. georg.kaehler@chir.ma.uni-heidelberg.de
authors.forename: G F B A
authors.initials: GF
authors.lastname: Kaehler
authors.forename: M G
authors.initials: MG
authors.lastname: Sold
authors.forename: K
authors.initials: K
authors.lastname: Fischer
authors.forename: S
authors.initials: S
authors.lastname: Post
authors.forename: M
authors.initials: M
authors.lastname: Enderle
mesh_terms: D000818:Animals; D001826:Body Fluids; D004210:Dissection / Q000295:instrumentation* / Q000379:methods; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005753:Gastric Mucosa / Q000601:surgery*; D007277:Injections, Jet / Q000295:instrumentation* / Q000379:methods; D013552:Swine; D014867:Water
chemical_list: D014867:Water