Narrow-band imaging optical chromocolonoscopy: Advantages and limitations

Abstract

Narrow-band imaging (NBI) is an innovative optical technology that modifies the center wavelength and bandwidth of an endoscope's light into narrow-band illumination of 415 ± 30 nm. NBI markedly improves capillary pattern contrast and is an in vivo method for visualizing microvessel morphological changes in superficial neoplastic lesions. The scientific basis for NBI is that short wavelength light falls within the hemoglobin absorption band, thereby facilitating clearer visualization of vascular structures. Several studies have reported advantages and limitations of NBI colonoscopy in the colorectum. One difficulty in evaluating results, however, has been nonstandardization of NBI systems (Sequential and nonsequential). Utilization of NBI technology has been increasing worldwide, but accurate pit pattern analysis and sufficient skill in magnifying colonoscopy are basic fundamentals required for proficiency in NBI diagnosis of colorectal lesions. Modern optical technology without proper image interpretation wastes resources, confuses untrained endoscopists and delays interinstitutional validation studies. Training in the principles of "optical image-enhanced endoscopy" is needed to close the gap between technological advancements and their clinical usefulness. Currently available evidence indicates that NBI constitutes an effective and reliable alternative to chromocolonoscopy for in vivo visualization of vascular structures, but further study assessing reproducibility and effectiveness in the colorectum is ongoing at various medical centers.

Non-sequential narrow band imaging for targeted biopsy and monitoring of gastric intestinal metaplasia

“…However, most GI endoscopists worldwide have no access to this system and instead, they are more familiar with the non-sequential system. Many endoscopists are impressed with the difference in the contrast and the brightness of the nonsequential image compared with those images published in the literature using sequential NBI [13,19] . Studies of the feasibility of NBI to detect a minute abnormality in the GI tract mucosa have been widely published [10][11][12][16][17][18] .…”

“…This system is not widely available for other commercial users. The slight differences in color spectrum of sequential and non-sequential NBI processors provide some differences in color images [13] . Therefore the excellent results from the sequential system may not be replicable in the non-sequential system.…”

Coeliac disease and the videocapsule: what have we learned till now

“…Local binary pattern (LBP) operators and wavelet transform subbands are both useful to subdivide regions of atrophy into a four-class system according to the Marsh score (36). Narrow-band imaging (NBI), which utilizes blue and green wavelengths of light for illumination, can be incorporated for contrast enhancement of vascular patterns on the mucosal surface (37). It is also possible to inspect multiple mucosal layers simultaneously for the presence of pathology, using confocal laser endomicroscopy, also known as visual biopsy (38).…”

Predicting Pathology in Medical Decision Support Systems in Endoscopy of the Gastrointestinal Tract

“…Chromoendoscopy aims at enhancing superficial patterns on a mucosal layer by topically applying color dyes. An alternative to this rather time-consuming procedure is to use Narrow Band Imaging (NBI), which allows to enhance the contrast of vascular patterns on the mucosal surface (Emura et al, 2008). Since NBI is based on a rotating filter in front of the light source (narrowing the spectrum of the visible light to bands of blue and green) this technique is not dependent on applying color dyes.…”