Detection of Colorectal Adenoma by Optical Enhancement Technology vs. High-Definition Colonoscopy

Colorectal cancer is the third most common cancer in the world.Colonoscopy is the gold standard screening test for colorectal cancer.There are also emerging data to support that screening by colonoscopy reduces both the incidence and mortality of colorectal cancer.However,Colonoscopy could still miss colorectal adenomas and even cancer.The miss rate for colonic adenomas was reported to be ranging from 15 to 32% in tandem colonoscopy studies.The reasons for the miss rate may be technical(insufficient during excessively fast instrument withdrawal),but may also be the imaging method.Smaller lesions ,particularly flat ones ,may be missed as a result of their subtle appearance and limited contrast in relation to the surrounding mucosa.

Some image-enhanced modules were developed with an aim to improve colorectal polyp or adenoma detection.The widely available modules is the narrow band imaging(NBI).However,most studies failed to demonstrate any superiority of NBI system over white light colonoscopy in detecting colonic polyps.NBI provides dimmer images of the colonic mucosa ,which may limit its performance on polyp and adenoma detection.

Like NBI,OE technology is image-enhanced module,providing a more intense look at the vascular pattern morphology.Besides,OE technology provides an much brighter image compared to NBI.This may possibly increase polyp detection by enhancing visibility of the colonic mucosa with brighter image.The current study aims to tested whether OE technology would improve adenoma detection when compared with high-definition colonoscopy.