title: Balloon overtube-guided colorectal endoscopic submucosal dissection.
abstract: OBJECTIVE
  To evaluate the usefulness of a balloon overtube to assist colorectal endoscopic submucosal dissection (ESD) using a gastroscope.
  
  
  METHODS
  The results of 45 consecutive patients who underwent colorectal ESD were analyzed in a single tertiary endoscopy center. In preoperative evaluation of access to the lesion, difficulties were experienced in the positioning and stabilization of a gastroscope in 15 patients who were thus assigned to the balloon-guided ESD group. A balloon overtube was placed with a gastroscope to provide an endoscopic channel to the lesion in cases with preoperatively identified difficulties related to accessibility. Colorectal ESD was performed following standard procedures. A submucosal fluid bleb was created with hyaluronic acid solution. A circumferential mucosal incision was made to marginate the lesion. The isolated lesion was finally excised from the deeper layers with repetitive electrosurgical dissections with needle knives. The success of colorectal ESD, procedural feasibility, and procedure-related complications were the main outcomes and measurements.
  
  
  RESULTS
  The overall en bloc excision rate of colorectal ESD during this study at our institution was 95.6%. En bloc excision of the lesion was successfully achieved in 13 of the 15 patients (86.7%) in the balloon overtube-guided colorectal ESD group, which was comparable to the results of the standard ESD group with better accessibility to the lesion (30/30, 100%, not statistically significant).
  
  
  CONCLUSIONS
  Use of a balloon overtube can improve access to the lesion and facilitate scope manipulation for colorectal ESD.
authors.affiliation: Department of Endoscopy, The Jikei University School of Medicine, 3-25-8 Nishi Shinbashi, Minato-ku, Tokyo 105-8461, Japan.
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Ohya
authors.forename: Ken
authors.initials: K
authors.lastname: Ohata
authors.forename: Kazuki
authors.initials: K
authors.lastname: Sumiyama
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Tsuji
authors.forename: Ikuro
authors.initials: I
authors.lastname: Koba
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Matsuhashi
authors.forename: Hisao
authors.initials: H
authors.lastname: Tajiri
mesh_terms: D000230:Adenocarcinoma / Q000601:surgery*; D000236:Adenoma / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D003113:Colonoscopy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000601:surgery*; D020699:Gastroscopes; D006801:Humans; D008875:Middle Aged