title: Ex vivo comparative study using the Endolifter® as a traction device for enhancing submucosal visualization during endoscopic submucosal dissection.
abstract: BACKGROUND
  Endoscopic submucosal dissection (ESD) is a technically demanding procedure, and exposure of the submucosa depends on the action of gravity and submucosal injection. The aim of the study was to investigate the effectiveness of the Endolifter(®) as a traction device for enhancing submucosal visualization during ESD.
  
  
  METHODS
  This was a prospective ex vivo comparative study conducted between September 2010 and March 2011 in the Prince of Wales Hospital. Consecutive ESDs were performed by four experienced endoscopists in an ex vivo ESD model with or without the Endolifter(®). The Endolifter(®) allows simultaneous grasping, retracting and lifting of the mucosa during ESD, resulting in exposure of the submucosa. Each of the procedures were recorded and reviewed later by two independent assessors. The outcome measures included the proportion of time that the submucosa was visualized during the procedures (SM ratio), procedural times, perforation rates, amount of submucosal injections, and the difficulty of the procedure.
  
  
  RESULTS
  Forty-eight gastric ESD procedures were performed on the model. The SM ratio was higher in the Endolifter(®) group (P = 0.007), particularly for lesions located at the antrum (P < 0.001). The time required for submucosal dissection and the total procedural time were also less in the Endolifter(®) group. The endoscopists rated the ESD procedures in the Endolifter(®) group as less difficult (P = 0.033).
  
  
  CONCLUSIONS
  The Endolifter(®) improved submucosal visualization during gastric ESD and reduces the difficulty of performing the procedures. The device may improve the ease of performing ESD in low-volume centers or large mucosal lesions.
authors.affiliation: Department of Surgery, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong SAR, China. anthonyteoh@surgery.cuhk.edu.hk
authors.forename: Anthony Yuen Bun
authors.initials: AY
authors.lastname: Teoh
authors.forename: Philip Wai Yan
authors.initials: PW
authors.lastname: Chiu
authors.forename: So Fei
authors.initials: SF
authors.lastname: Hon
authors.forename: Tony Wing Chung
authors.initials: TW
authors.lastname: Mak
authors.forename: Enders Kwok Wai
authors.initials: EK
authors.lastname: Ng
authors.forename: James Yun Wong
authors.initials: JY
authors.lastname: Lau
mesh_terms: D000818:Animals; D004210:Dissection / Q000295:instrumentation* / Q000379:methods*; D004867:Equipment Design; D005753:Gastric Mucosa / Q000473:pathology* / Q000601:surgery*; D005773:Gastroscopy / Q000379:methods*; D066298:In Vitro Techniques; D008953:Models, Anatomic; D013552:Swine