title: Use of narrow band imaging in assessing duodenal villous atrophy.
abstract: OBJECTIVE
  Narrow band imaging endoscopy with magnification (NBI-ME) has already been established in Barrett's esophagus, stomach, and colonic mucosa, but limited work has been done in the mucosal evaluation of duodenum. A study was done to determine the correlation between NBI and histology in grading villous architecture in varied etiology.
  
  
  METHODS
  A prospective observational study comprising 105 subjects with suspected malabsorption. The presence of a diagnosed celiac disease, severe life threatening comorbidity, or pregnancy was considered as exclusion criteria. Standard endoscopy (SE), NBI-ME, multiple duodenal biopsies with histopathological examination were done in all.
  
  
  RESULTS
  Fifty-one patients had celiac disease while 54 patients comprised mainly functional dyspepsia, iron deficiency anemia, tropical malabsorption syndrome, and irritable bowel syndrome. Four NBI-ME image subtypes of villous morphology have been proposed (NBI type I/II/III/IV). NBI-ME had 95 % sensitivity, 90.2 % specificity, 91.2 % positive predictive value, and 94.2 % negative predictive value for diagnosing altered villous morphology. Intraobserver kappa agreement coefficient (κ) for NBI-ME was 0.83 while interobserver agreement was 0.89 (95 % CI 0.8-0.97).
  
  
  CONCLUSIONS
  NBI-ME has good performance characteristics and very good kappa intra/interobserver agreement coefficient for varied subtypes of villous morphology. NBI-ME is most useful for obtaining a targeted biopsy which can be missed by conventional white light endoscopy.
authors.affiliation: Department of Gastroenterology, Dr. Sampurnanand Medical College, Jodhpur, 342 003, India, amitavagoswami77@gmail.com.
authors.forename: Amitava
authors.initials: A
authors.lastname: Goswami
authors.forename: Sunil
authors.initials: S
authors.lastname: Dadhich
authors.forename: Narendra
authors.initials: N
authors.lastname: Bhargava
mesh_terms: D000293:Adolescent; D000328:Adult; D001284:Atrophy; D001706:Biopsy / Q000379:methods; D002446:Celiac Disease / Q000473:pathology*; D002648:Child; D002675:Child, Preschool; D004386:Duodenum / Q000473:pathology*; D016099:Endoscopy, Gastrointestinal / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D055815:Young Adult