title: Narrow band imaging for characterization of high grade dysplasia and specialized intestinal metaplasia in Barrett's esophagus: a meta-analysis.
abstract: OBJECTIVE
  Narrow band imaging (NBI), a novel endoscopic technique that highlights mucosal surface structures and microvasculature is increasingly advocated as a tool to detect and characterize neoplasia and intestinal metaplasia in patients with Barrett's esophagus. We aimed to assess the diagnostic accuracy of NBI with magnification for the diagnosis of high grade dysplasia (HGD) and specialized intestinal metaplasia (SIM) in patients with Barrett's esophagus.
  
  
  METHODS
  We performed a meta-analysis of studies which compared NBI-based diagnosis of HGD and SIM with histopathology as the gold standard.
  
  
  RESULTS
  Eight studies including 446 patients with 2194 lesions met the inclusion criteria. For diagnosing HGD, the pooled sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC) were 0.96 (95 % confidence interval [CI] 0.93-0.99), 0.94 (95 %CI 0.84-1.0), 342.49 (95 %CI 40.49 - 2896.89) and 0.99 (SE 0.01) on a per-lesion analysis with similar results on per-patient analysis.. For the characterization of SIM, the pooled sensitivity, specificity, DOR, and AUC were 0.95 (95 %CI 0.87-1.0), 0.65 (95 %CI 0.52-0.78), 37.53 (95 %CI 6.50-217.62) and 0.88 (SE 0.08) on a per-lesion analysis.
  
  
  CONCLUSIONS
  NBI with magnification is accurate with high diagnostic precision for diagnosis of HGD in Barrett's esophagus on the basis of irregular mucosal pit patterns and/or irregular microvasculature. NBI has high sensitivity but poor specificity for characterizing SIM.
authors.affiliation: Nottingham Digestive Diseases Centre, NIHR Biomedical Research Unit, Queens Medical Centre Campus, University of Nottingham, UK.
authors.forename: J
authors.initials: J
authors.lastname: Mannath
authors.forename: V
authors.initials: V
authors.lastname: Subramanian
authors.forename: C J
authors.initials: CJ
authors.lastname: Hawkey
authors.forename: K
authors.initials: K
authors.lastname: Ragunath
mesh_terms: D001471:Barrett Esophagus / Q000473:pathology*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D004945:Esophagoscopy / Q000379:methods; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007413:Intestinal Mucosa / Q000473:pathology*; D008679:Metaplasia; D015588:Observer Variation; D011230:Precancerous Conditions / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity