Narrow-band imaging in the diagnosis of colorectal mucosal lesions: A pilot study

Background and Study Aims: A newly developed narrow-band imaging (NBI) technique, in which modified optical filters were used in the light source of a video endoscope system, was applied during colonoscopy in a clinical setting. This pilot study evaluated the clinical feasibility of the NBI system for evaluating colorectal lesions. Patients and Methods: A total of 43 colorectal lesions in 34 patients were included in the study. The quality of visualization of colorectal lesions and the accuracy of differentiation between neoplastic and non-neoplastic lesions using the NBI system were evaluated in comparison with results from conventional colonoscopy and with chromoendoscopy. Results: For pit pattern delineation, NBI was superior to conventional endoscopy (P < 0.001 ), but inferior to chromoendoscopy (P < 0.05. NBI achieved better visualization of the mucosal vascular network and of the hue of lesions than conventional endoscopy (P < 0.05). However there was no significant difference between NBI and chromoendoscopy in differentiating neoplastic from non-neoplastic lesions (both techniques had a sensitivity of 100% and a specificity 75%). This was better than the results of conventional colonoscopy (sensitivity 83%, specificity 44%; P < 0.05 for specificity). Conclusions: These results suggest that in the examination of colonic lesions the NBI system provides imaging features additional to those of both conventional endoscopy and chromoendoscopy. For distinguishing neoplasms from non-neoplastic lesions, NBI was equivalent to chromoendoscopy.