title: A novel extra-wide-angle-view colonoscope: a simulated pilot study using anatomic colorectal models.
abstract: BACKGROUND
  A major factor that may contribute to a higher adenoma miss rate during colonoscopy is undetected lesions located behind haustral folds, flexures, or rectal valves.
  
  
  OBJECTIVE
  To assess the efficacy of a prototype, novel, extra-wide-angle-view colonoscope that provides a simultaneous lateral-backward view that complements the forward view lens.
  
  
  METHODS
  A simulated pilot study of two anatomic colorectal models, each prepared with 8 polyps positioned in obvious locations and 8 polyps placed behind folds. Thirty-two endoscopists with different levels of experience performed examinations on models in a random order by using the extra-wide-angle-view colonoscope and a standard colonoscope.
  
  
  METHODS
  The detection rates of simulated polyps.
  
  
  RESULTS
  The mean detection rate for all simulated polyps with the extra-wide-angle-view colonoscope was significantly higher than that with the standard colonoscope (68% vs 51%; P < .0001). The detection rate for polyps behind folds was significantly higher in the extra-wide-angle-view colonoscope than in the standard colonoscope (61.7% vs 46.9%; P = .0009).
  
  
  CONCLUSIONS
  Not a clinical study.
  
  
  CONCLUSIONS
  The novel, extra-wide-angle-view colonoscope may represent an advancement in colorectal polyp detection. The value of the colonoscope for clinical use awaits further study.
authors.affiliation: Division of Research and Development for Minimally Invasive Treatment, Cancer Center, School of Medicine, Keio University, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Uraoka
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanaka
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Takahisa
authors.initials: T
authors.lastname: Matsuda
authors.forename: Shiro
authors.initials: S
authors.lastname: Oka
authors.forename: Tomohiko
authors.initials: T
authors.lastname: Moriyama
authors.forename: Reiji
authors.initials: R
authors.lastname: Higashi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Saito
mesh_terms: D003106:Colon; D003111:Colonic Polyps / Q000175:diagnosis*; D020685:Colonoscopes; D003113:Colonoscopy / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008953:Models, Anatomic; D055096:Optical Devices; D010865:Pilot Projects; D011897:Random Allocation; D013997:Time Factors