Narrow-band imaging on screening of esophageal lesions using an ultrathin transnasal endoscopy

Background and Aim: Ultrathin transnasal endoscopy, used extensively in Japan, is considered to have inferior image quality and suction performance, and questionable diagnostic performance. So the aim of the present study was to compare the diagnostic performance of white light (WL) examination and non-magnified narrow-band imaging (NBI) examination in screening for esophageal disorders with ultrathin transnasal endoscopy. Methods: A prospective case study of 105 consecutive patients screened for upper gastrointestinal disorders at a single clinic in Tokyo Medical University Hospital. All subjects were diagnosed using WL, NBI and Lugol-staining examinations. Areas >= 5 mm clearly not a Lugol-staining lesion were defined as esophageal disorders and the rates of detection of the two examination methods (WL vs NBI) were compared. Results: For WL examination, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy (concordance rate) for esophageal disorders were 19.6%, 98.1%, 90.9%, 55.4%, and 59.2%, respectively, versus 60.8% 96.2%, 93.9%, 71.4%, and 78.6% for NBI. Conclusion: A useful level of diagnostic performance for esophageal disorders can be achieved with non-magnified narrow-band NBI ultrathin transnasal endoscopy.