Performance of Narrow Band Imaging and Magnification Endoscopy in the Prediction of Therapeutic Response in Patients With Gastroesophageal Reflux Disease

Background: Imaging-enhanced endoscopy enhances the contrast of the mucosal surface and helps in the diagnosis of gastroesophageal reflux disease. However, whether the increased detection of subtle erosive foci corresponds to the effect of acid suppression remains elusive. Goals: We aim to evaluate the utility of narrow band imaging with and without magnification endoscopy in the prediction of therapeutic response in patients with reflux. Study: Endoscopic evaluation with conventional white light, narrow band imaging, and narrow band imaging with magnification was performed sequentially in consecutive patients with reflux. All patients received proton pump inhibitor for 14 days. Their therapeutic responses were correlated with the baseline endoscopic findings, including mucosal breaks under standard endoscopy, mucosal brownish changes under narrow band imaging, and increased and/or dilated intrapapillary capillary loops or microerosions under narrow band imaging with magnification. Results: Of a total of 82 patients, 22 (26.8%) patients were diagnosed with erosive disease under standard endoscopy. Among the remaining 60 (73.2%) patients, 14 (23.3%) and 30 (50%) were considered erosive under narrow band imaging and narrow band imaging with magnification, respectively. Sixty-five (79.3%) patients showed a positive therapeutic response. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in predicting therapeutic response were 33.8%, 100%, 100%, 28.3%, and 47.6%, respectively, for standard endoscopy; 52.3%, 88.2%, 94.4%, 32.6%, and 59.8%, respectively, for narrow band imaging; and 70.8%, 64.7%, 88.4%, 36.6%, and 69.5%, respectively, for narrow band imaging with magnification. Conclusions: Narrow band imaging with and without magnification endoscopy substantially improve our ability to predict therapeutic response in patients with gastroesophageal reflux.