Does Autofluorescence Imaging Videoendoscopy System Improve the Colonoscopic Adenoma Detection Rate?-A Prospective Study

Abstract

Background: Colonoscopy is considered as the gold standard for the detection of colorectal adenomas, however, overlooking of neoplastic lesions are well documented. Autofluorescence imaging (AFI) system is an emerging technique for neoplasia detection, including the gastrointestinal tract. Aim: The aim of this randomized prospective study is to value whether an AFI videoendoscopy system can improve the colorectal adenoma detection rate, as compared to conventional white light (WL) colonoscopy. Methods: Between June and October 2006, a total of 167 consecutive patients were enrolled in this study, and underwent modified back-to-back colonoscopy using AFI system (XCF-H240FZI video colonoscope, Olympus Corp., Tokyo, Japan) by a single experienced colonoscopist. Each patient was randomized in one of two groups; Group A: examination from the cecum to the splenic flexure with AFI, and then with WL after having reinserted the scope to the cecum; Group B: examination in an inverse order than in Group A (first WL and then AFI examination). The time consumption and the number of detected lesions were recorded for both the first and second examinations. In both groups, all visualized lesions diagnosed as neoplasia were removed and sent individually for histopathological examination. Results: Eighty-three patients were randomized to Group A and 84 to B. Indications for colonoscopy were similar between both groups. There was no difference in the duration of withdrawal between the first and second examination in both groups. The total number of neoplastic lesions detected by AFI and WL colonoscopy was 92 and 69 respectively (p = 0.055). Among the 66 neoplastic lesions in group A, 47 (71%) were detected by with the first withdrawal technique (AFI). On the other hand, among the 95 neoplastic lesions in group B, 50 (53%) were detected at the first withdrawal technique (WL), and 45 (47%) lesions were detected by second AFI examination (p = 0.018). Characteristics of the missed lesions by WL colonoscopy in group B were as follows; flat lesion: 39 (87%), diminutive (≦5 mm) polyp: 41 (91%), low-grade dysplasia (LGD): 45 (100%). Conclusion: AFI videoendoscopy system might be useful for the detection of colorectal adenomas compared to conventional (white light) colonoscopy, especially for flat and/or diminutive lesions.