Image assessment of Barrett's esophagus using the simplified narrow band imaging classification

A simplified narrow band imaging (NBI) classification has been proposed with the objective of integrating multiple classifications of NBI surface patterns in Barrett’s esophagus (BE). Little is known about the impact of the simplified NBI classification on the diagnosis of BE when using high-definition magnification endoscopy with NBI (HM-NBI). This study aimed to evaluate (a) the reproducibility of NBI surface patterns and predicted histology and (b) the diagnostic accuracy of interpreting HM-NBI images by using the simplified NBI classification. Two hundred and forty-eight HM-NBI images from macroscopically normal areas in patients with BE were retrieved from endoscopy databases and randomized for review by four endoscopists (two experts, two non-experts). We evaluated inter- and intra-observer agreement of the interpretation of NBI surface patterns and the predicted histology (dysplasia vs. non-dysplasia), as calculated by using κ statistics, and diagnostic values of the prediction. The overall inter-observer agreements were substantial for mucosal pattern (κ = 0.73) and vascular pattern (κ = 0.71), and almost perfect for predicting dysplastic histology (κ = 0.80). The overall intra-observer agreements were almost perfect for mucosal (κ = 0.84) and vascular patterns (κ = 0.86), and predicting dysplastic histology (κ = 0.89). The mean accuracy in predicting dysplastic histology for all reviewers was 95 % (experts: 96.8 %, non-experts: 93.1 %). The simplified NBI classification has the potential to provide high diagnostic reproducibility and accuracy when using HM-NBI.