C. PRELIMINARY DATA Our group recently assessed the potential of NBI for the prediction of histology during screening and surveillance endoscopy in BE patients (10). Images obtained by this system were classified according to the mucosal (ridge/villous, circular, irregular/distorted) and vascular (normal, abnormal) patterns and correlated with histology in a prospective and blinded fashion. The sensitivity, specificity, and positive predictive value of the ridge/villous pattern for the diagnosis of intestinal metaplasia without high-grade dysplasia (HGD) were 93.5%, 87%, and 95% respectively. The sensitivity, specificity, and positive predictive value of the irregular/distorted patterns for HGD were 100%, 99%, and 95% respectively. These promising results have been validated by other investigators. Similarly, Dr. Sharma has published several studies involving the use of chromoendoscopy in patients with BE. In a study of 80 patients with columnar lined esophagus using indigo carmine dye and 115x magnification endoscopy, three mucosal patterns as stated above were identified. The presence of ridge/villous pattern for detecting intestinal metaplasia had high sensitivity, specificity, and positive predictive value (97%, 76%, and 92% respectively). Six patients had an irregular/distorted pattern and biopsies revealed HGD in all these patients (11). Our group has been active in evaluating the role of ablative therapies in patients with BE.