Computed virtual chromoendoscopy for classification of small colorectal lesions: a prospective comparative study.

ABSTRACT

OBJECTIVES: Standard colonoscopy offers no reliable discrimination between neoplastic and nonneoplastic colorectal lesions. Computed virtual chromoendoscopy with the Fujinon intelligent color enhancement (FICE) system is a new dyeless imaging technique that enhances mucosal and vascular patterns. This prospective trial compared the feasibility of FICE, standard colonoscopy, and conventional chromoendoscopy with indigo carmine in low- and high-magnification modes for determination of colonic lesion histology. METHODS: Sixty-three patients with 150 flat or sessile lesions less than 20 mm in diameter were enrolled. At colonoscopy, each lesion was observed with six different endoscopic modalities standard colonoscopy, FICE, and conventional chromoendoscopy with indigo carmine (0.2%) dye spraying in both low- and high-magnification modes. Histopathology of all lesions was confirmed by evaluation of endoscopic resection or biopsy specimens. Endoscopic images were stored electronically and randomly allocated to a blinded reader. RESULTS: Of the 150 polyps, 89 were adenomas and 61 were hyperplastic polyps with an average size of 7 mm. For identifying adenomas, the FICE system with low and high magnifications revealed a sensitivity of 89.9% and 96.6%, specificity of 73.8% and 80.3%, and diagnostic accuracy of 83% and 90%, respectively. Compared with standard colonoscopy, the sensitivity and diagnostic accuracy achieved by FICE were significantly better under both low (P < 0.02) and high (P < 0.03) magnification and were comparable to that of conventional chromoendoscopy. CONCLUSIONS: The FICE system identified morphological details that efficiently predict adenomatous histology. For distinguishing neoplastic from nonneoplastic lesions, FICE was superior to standard colonoscopy and equivalent to conventional chromoendoscopy.