Review
Copyright ©2008 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Aug 21, 2008; 14(31): 4867-4872
Published online Aug 21, 2008. doi: 10.3748/wjg.14.4867
Narrow-band imaging optical chromocolonoscopy: Advantages and limitations
Fabian Emura, Yutaka Saito, Hiroaki Ikematsu
Fabian Emura, Advanced Digestive Endoscopy, EmuraCenter LatinoAmerica & Emura Foundation for the Promotion of Cancer Research, and Universidad de La Sabana Medical School, Bogotá DC, Colombia
Yutaka Saito, Endoscopy Division, National Cancer Center Hospital, Tokyo 104-0045, Japan
Hiroaki Ikematsu, Endoscopy Division, National Cancer Center Hospital East, Chiba 277-8577, Japan
Author contributions: All authors contributed significantly in the paper; Emura F contributed to scientific design and paper work; Saito Y contributed to manuscript edition and critical scientific concepts; Ikematsu H contributed to figures draft and data analysis.
Correspondence to: Yutaka Saito, MD, PhD, Endoscopy Division, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan. ytsaito@ncc.go.jp
Telephone: +81-3-35422511 Fax: +81-3-35423815
Received: April 18, 2008
Revised: June 30, 2008
Accepted: July 7, 2008
Published online: August 21, 2008
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 non-standardization of NBI systems (Sequential and non-sequential). 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 inter-institutional 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.

Keywords: Narrow-band imaging; Colonoscopy; Sequential system; Non-sequential system; Polyps; Chromoendoscopy