title: Overtube-balloon-assisted direct peroral cholangioscopy by using an ultra-slim upper endoscope (with videos).
abstract: BACKGROUND
  The "mother-baby" endoscope system currently used for peroral cholangioscopy (POC) has several limitations. Endoscopic direct cholangioscopy when using an ultra-slim upper endoscope with a guidewire to maintain access has been reported, but appropriate accessories are required to increase the success rate. Herein, we describe a novel method, overtube-balloon-assisted endoscopy, for direct POC.
  
  
  OBJECTIVE
  To evaluate the feasibility and usefulness of direct POC when using an ultra-slim upper endoscope with an overtube balloon to maintain access.
  
  
  METHODS
  A single center.
  
  
  METHODS
  Case series.
  
  
  METHODS
  Twelve patients with biliary disease.
  
  
  METHODS
  Direct POC by using an ultra-slim upper endoscope and diagnostic and/or therapeutic procedures.
  
  
  METHODS
  Success rate of this technique, diagnostic or therapeutic feasibility, and complications.
  
  
  RESULTS
  Overtube-balloon-assisted direct POC was performed successfully in 10 of 12 patients (83.3%). The procedure revealed 4 common bile duct (CBD) stones, 4 benign biliary strictures, 1 polypoid tumor, and 1 cholangiocarcinoma. Five patients underwent forceps biopsy under direct visualization of the intraductal lesion. Laser lithotripsy was successfully performed in 1 patient. No procedure-related complication occurred.
  
  
  CONCLUSIONS
  A small number of patients and no comparison with conventional cholangioscopy.
  
  
  CONCLUSIONS
  The overtube balloon appears to be a useful accessory in direct POC when using an ultra-slim upper endoscope. However, further development of a slim overtube or other accessories is necessary to improve the success rate of direct POC.
authors.affiliation: Department of Internal Medicine, Digestive Disease Center, Soon Chun Hyang University School of Medicine, Bucheon and Seoul, Korea.
authors.forename: Hyun Jong
authors.initials: HJ
authors.lastname: Choi
authors.forename: Jong Ho
authors.initials: JH
authors.lastname: Moon
authors.forename: Bong Min
authors.initials: BM
authors.lastname: Ko
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Hong
authors.forename: Hyun Cheol
authors.initials: HC
authors.lastname: Koo
authors.forename: Young Koog
authors.initials: YK
authors.lastname: Cheon
authors.forename: Young Deok
authors.initials: YD
authors.lastname: Cho
authors.forename: Joon Seong
authors.initials: JS
authors.lastname: Lee
authors.forename: Moon Sung
authors.initials: MS
authors.lastname: Lee
authors.forename: Chan Sup
authors.initials: CS
authors.lastname: Shim