title: Clip retention rates and rates of residual polyp at the base of retained clips on colorectal EMR sites.
abstract: OBJECTIVE
  Prophylactic endoscopic clipping may be effective in preventing delayed post-polypectomy hemorrhage after EMR of large colorectal lesions. The rate of retention of hemoclips on EMR sites has not been fully described. The aim of this study was to evaluate the adherence rates of hemoclips placed after EMR of large colorectal lesions.
  
  
  METHODS
  This was a retrospective review of a prospectively maintained database of large colorectal polyps (≥20 mm) referred to Indiana University Hospital between June 2006 and August 2015. Sites were closed with a mean of 4 clips. Patients were followed up for 3 to 6 months after EMR with a second follow-up 1 year later. Biopsy specimens of EMR scars were examined at follow-up, including the tissue at the base of retained clips.
  
  
  RESULTS
  There were 479 EMR sites in 424 patients that had first follow-up at our center with high-quality photographs of the EMR sites taken immediately after clip placement and at follow-up. Of 1407 Boston Scientific Resolution clips placed, 59 (4.2%) were retained at follow-up. Of 532 Cook Instinct clips placed, 46 (8.6%) were retained at first follow-up (P = .0001). There was no difference in the follow-up interval for the 2 clips. No patient had residual polyp by biopsy at the base of a retained clip.
  
  
  CONCLUSIONS
  Clip retention at first follow-up at 3 to 6 months after EMR was twice as high for the Cook Instinct clip compared with Boston Resolution clip but retention rates were low for both clips. Residual polyp at the base of retained clips was not a significant clinical problem.
authors.affiliation: Indiana University School of Medicine, Division of Gastroenterology and Hepatology, Indianapolis, Indiana, USA.
authors.forename: Prasanna L
authors.initials: PL
authors.lastname: Ponugoti
authors.affiliation: Indiana University School of Medicine, Division of Gastroenterology and Hepatology, Indianapolis, Indiana, USA.
authors.forename: Douglas K
authors.initials: DK
authors.lastname: Rex
mesh_terms: D000236:Adenoma / Q000601:surgery*; D000368:Aged; D003106:Colon; D003111:Colonic Polyps / Q000601:surgery*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000601:surgery*; D016208:Databases, Factual; D000069916:Endoscopic Mucosal Resection; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D005547:Foreign Bodies / Q000453:epidemiology*; D006801:Humans; D007417:Intestinal Polyps / Q000601:surgery; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual; D019106:Postoperative Hemorrhage / Q000517:prevention & control; D012007:Rectum; D012189:Retrospective Studies; D013525:Surgical Instruments