title: Carbon dioxide submucosal injection cushion: an innovative technique in endoscopic submucosal dissection.
abstract: OBJECTIVE
  Endoscopic submucosal dissection (ESD) can successfully resect large lesions en bloc, but it requires a satisfactory submucosal (sm) injection agent for proper safety and efficacy. The aim of the present study was to evaluate the effectiveness of carbon dioxide (CO(2) ) as an ESD sm injection agent.
  
  
  METHODS
  In vitro study using porcine stomachs compared CO(2) with normal saline (NS) and sodium hyaluronic acid (SHA) solution, both of which are currently used to provide long-lasting sm elevation during ESD. Histopathological examination assessed differences between CO(2) and NS sm cushions. ESD were then carried out in vivo in the stomach and rectum of a live pig using CO(2) sm injection.
  
  
  RESULTS
  CO(2) sm elevation was significantly longer lasting than either NS or SHA (P<0.001). Histopathology revealed no mucosal layer tissue damage, and dissection of honeycomb-like fibrous connective tissue in the CO(2) sm cushion. Creating and maintaining a CO(2) sm cushion of sufficient elevation combined with partial physical dissection of the sm layer was achieved, followed by complete endoscopic dissection of the sm layer with all ESD, resulting in successful en-bloc resections having a mean specimen size of 24.3mm within 15min.
  
  
  CONCLUSIONS
  Safety and efficacy of CO(2) as a satisfactory sm injection agent during ESD was successfully demonstrated in these preliminary studies, warranting further investigation of this innovative technique.
authors.affiliation: Department of Endoscopy, Okayama University Hospital, Japan. toshi_urao@yahoo.co.jp
authors.forename: Toshio
authors.initials: T
authors.lastname: Uraoka
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Kawahara
authors.forename: Nobuya
authors.initials: N
authors.lastname: Ohara
authors.forename: Jun
authors.initials: J
authors.lastname: Kato
authors.forename: Keisuke
authors.initials: K
authors.lastname: Hori
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Okada
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage*; D004210:Dissection / Q000379:methods*; D004724:Endoscopy / Q000379:methods*; D007413:Intestinal Mucosa / Q000601:surgery*; D013552:Swine
chemical_list: D002245:Carbon Dioxide