title: Mucosal morphology in Barrett's esophagus: interobserver agreement and role of narrow band imaging.
abstract: OBJECTIVE
  We have recently proposed a classification of mucosal morphology in Barrett's esophagus based on three criteria: regularity of mucosal pattern, regularity of vascular pattern, and presence of abnormal blood vessels. We aimed to evaluate the interobserver agreement with the proposed mucosal morphology classification and to assess the additional value of narrow band imaging (NBI) over high resolution white light endoscopy (HR-WLE).
  
  
  METHODS
  Five international experts in the field of Barrett's imaging and seven community endoscopists with no expertise in this field independently evaluated magnified still images from 50 areas, obtained with HR-WLE and NBI, in Barrett's esophagus patients. Visual analogue scales (VAS) were used for scoring imaging quality. Interobserver agreement for mucosal morphology and yield for identifying early neoplasia were assessed.
  
  
  RESULTS
  Imaging qualities of NBI were rated more highly than HR-WLE, when evaluated separately as well as in a side-by-side comparison. The interobserver agreement ranged from 0.40 to 0.56 and did not significantly differ between expert and non-expert endoscopists. The overall yield for correctly identifying images of early neoplasia was 81 % for HR-WLE, 72 % for NBI and 83 % for HR-WLE + NBI, with no significant difference between experts and non-experts.
  
  
  CONCLUSIONS
  Interobserver agreement for the classification of mucosal morphology was moderate. Although NBI was rated more highly than HR-WLE for imaging quality, this did not result in improved interobserver agreement or increased yield for identifying early neoplasia in Barrett's esophagus. This applied to non-expert as well as expert endoscopists.
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: W L
authors.initials: WL
authors.lastname: Curvers
authors.forename: C J
authors.initials: CJ
authors.lastname: Bohmer
authors.forename: R C
authors.initials: RC
authors.lastname: Mallant-Hent
authors.forename: A H
authors.initials: AH
authors.lastname: Naber
authors.forename: C I
authors.initials: CI
authors.lastname: Ponsioen
authors.forename: K
authors.initials: K
authors.lastname: Ragunath
authors.forename: R
authors.initials: R
authors.lastname: Singh
authors.forename: M B
authors.initials: MB
authors.lastname: Wallace
authors.forename: H C
authors.initials: HC
authors.lastname: Wolfsen
authors.forename: L-M Wong Kee
authors.initials: LM
authors.lastname: Song
authors.forename: R
authors.initials: R
authors.lastname: Lindeboom
authors.forename: P
authors.initials: P
authors.lastname: Fockens
authors.forename: J J
authors.initials: JJ
authors.lastname: Bergman
mesh_terms: D001471:Barrett Esophagus / Q000145:classification / Q000473:pathology*; D002277:Carcinoma / Q000473:pathology*; D002983:Clinical Competence; D004724:Endoscopy; D004938:Esophageal Neoplasms / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement; D008027:Light; D008853:Microscopy; D009092:Mucous Membrane / Q000098:blood supply / Q000473:pathology*; D015588:Observer Variation; D011230:Precancerous Conditions / Q000473:pathology*; D015203:Reproducibility of Results; D012189:Retrospective Studies