title: The addition of high magnifying endoscopy improves rates of high confidence optical diagnosis of colorectal polyps.
abstract: OBJECTIVE
  The real-time optical diagnosis of colorectal polyps with high confidence predictions can achieve high levels of accuracy. Increasing the rates of high confidence optical diagnosis can improve the clinical application of real-time optical diagnosis in routine practice. The primary aim of this prospective study was to evaluate whether high magnifying endoscopy improves the rates of high confidence narrow-band imaging (NBI) - based optical diagnosis for differentiating between neoplastic and non-neoplastic colorectal lesions according to the NBI international colorectal endoscopic (NICE) classification.
  
  
  METHODS
  Consecutive adult patients undergoing colonoscopy with a high magnifying (maximum, × 80) colonoscope between April and August 2012 were recruited. The optical diagnosis for each polyp was evaluated during colonoscopy in two consecutive stages by the same endoscopist, who first used NBI with non-magnifying endoscopy (NBI-NME), then NBI with magnifying endoscopy (NBI-ME). A level of confidence was assigned to each prediction.
  
  
  RESULTS
  The analysis included 124 patients (mean age, 56.4 years; male-to-female ratio, 72:52) with 248 polyps smaller than 10 mm. Of the 248 polyps, 210 were 1 to 5 mm in size and 38 were 6 to 9 mm in size; 77 polyps were hyperplastic, 4 were sessile serrated adenomas/polyps, 160 were low grade adenomas, 5 were high grade adenomas, and 2 were deep submucosal invasive carcinomas. The rate of high confidence optical diagnosis when NBI-ME was used was significantly higher than the rate when NBI-NME was used for diminutive (1 - 5 mm) polyps (92.9 % vs 79.5 %, P < 0.001) and for small (6 - 9 mm) polyps (94.7 % vs 84.2 %, P = 0.048).
  
  
  CONCLUSIONS
  High magnifying endoscopy significantly improved the rates of high confidence NBI-based optical diagnosis of diminutive and small colorectal polyps.
  
  
  BACKGROUND
  UMIN 000007608.
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Mineo
authors.initials: M
authors.lastname: Iwatate
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Sano
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Santa
authors.initials: S
authors.lastname: Hattori
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Sano
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Noriaki
authors.initials: N
authors.lastname: Hasuike
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Ikumoto
authors.affiliation: Sano Hospital, Gastrointestinal Center, Kobe, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Kotaka
authors.affiliation: Department of Medical Statistics, Toho University, Tokyo, Japan.
authors.forename: Yoshitaka
authors.initials: Y
authors.lastname: Murakami
authors.affiliation: University of Queensland School of Medicine, Brisbane, Australia.
authors.forename: David G
authors.initials: DG
authors.lastname: Hewett
authors.affiliation: Gastroenterology, Stanford University School of Medicine, Palo Alto, California, USA.
authors.forename: Roy
authors.initials: R
authors.lastname: Soetikno
authors.affiliation: Gastroenterology, Stanford University School of Medicine, Palo Alto, California, USA.
authors.forename: Tonya
authors.initials: T
authors.lastname: Kaltenbach
authors.affiliation: Department of Surgical and Molecular Pathology, Dokkyo University School of Medicine, Tochigi, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Fujimori