title: Narrow-band imaging flexible cystoscopy: a new user's experience.
abstract: OBJECTIVE
  We and others have demonstrated previously an improved detection rate for bladder cancer recurrences with narrow-band imaging (NBI) flexible cystoscopy when compared with conventional white-light imaging (WLI) flexible cystoscopy. We investigated whether a "new user" of NBI flexible cystoscopy, previously unfamiliar with this technique, could reproduce these results.
  
  
  METHODS
  The same protocol from our previous study was used by a new user (ZHS) for this second study at The Queen Elizabeth Hospital, Birmingham, United Kingdom. NBI flexible cystoscopy was performed on 23 patients with known recurrences of urothelial cancer (UC) of the bladder after initial conventional WLI flexible cystoscopy with the same switchable Olympus Lucera sequential red/green/blue instrument.
  
  
  RESULTS
  NBI detected 15 additional UCs in 8 of the 23 (35%) patients: Six of these patients had one additional UC, one had four additional UCs, and one had five additional UCs when compared with WLI, with a mean of 0.65 additional UCs per patient (standard deviation 1.30; Wilcoxon P = 0.01). When this second series is compared with our first published series, there is no statistical evidence that the excess number of UCs detected by NBI is different (Wilcoxon [unpaired] signed-rank test P = 0.74), which suggests that there is no difference between a new user and an experienced user in the application of NBI.
  
  
  CONCLUSIONS
  We and others continue to demonstrate a significantly improved detection rate of bladder UCs with NBI cystoscopy when compared with conventional WLI cystoscopy, even for new users previously unfamiliar with this technology.
authors.affiliation: Department of Public Health, Epidemiology and Biostatistics, and School of Cancer Sciences, University of Birmingham, Birmingham, United Kingdom. rtbryan@dsl.pipex.com
authors.forename: Richard T
authors.initials: RT
authors.lastname: Bryan
authors.forename: Zaheer H
authors.initials: ZH
authors.lastname: Shah
authors.forename: Stuart I
authors.initials: SI
authors.lastname: Collins
authors.forename: D Michael A
authors.initials: DM
authors.lastname: Wallace
mesh_terms: D003558:Cystoscopy / Q000379:methods*; D003952:Diagnostic Imaging / Q000379:methods*; D006801:Humans; D008027:Light; D018583:Pliability; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis