Narrow band imaging: a wide field of possibilities.

The application of opto-electronic in video-endoscopes aims to improve accuracy in diagnosis, through image processing and digital technology. Narrow band imaging (NBI), one of the most recent techniques, consists of using interference filters for the illumination of the target in narrowed red, green, and blue (R/G/B) bands of the spectrum. This results in different images at distinct levels in the mucosa and increases the contrast of the epithelial surface and of the subjacent vascular network. NBI is combined to magnifying endoscopy with an optical zoom. After being studied in prototypes the opto-electronic technique, now available in the most recent models of video-endoscopes that use the sequential R/G/B system of illumination, should be adapted in the near future for the instruments utilizing the non-sequential system of illumination. This new technique aims to characterize the surface of the distinct types of digestive epithelia, including intestinal metaplasia in the Barrett's esophagus. The technique also allows characterizing the disorganization of the vascular pattern in inflammatory disorders of the digestive mucosa and in superficial neoplastic lesions in the esophagus, stomach, and large bowel.