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

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.