A prospective randomized study on computed virtual chromoendoscopy versus conventional colonoscopy for the detection of small colorectal adenomas.

BACKGROUND: Colonoscopy is considered to be the standard diagnostic test for detecting colonic neoplasia, particularly for small lesions. However, recent publications have suggested that 15-27% of small adenomas might be missed during conventional colonoscopy.

AIMS: To determine whether computed virtual chromoendoscopy (CVC) can improve the detection of small adenomas as compared to conventional colonoscopy.

METHODS: We examined 135 consecutive patients by total colonoscopy and 128 patients were randomized to compare white-light colonoscopy (65 patients) and CVC-mode colonoscopy (63 patients) after the exclusion of seven patients because of poor bowel preparation (n = 4) or other causes (one sigmoid colon cancer, two intestinal tuberculosis).

RESULTS: There were no differences between the patient characteristics for the two study groups, i.e., age, sex, body mass index, quality of bowel preparations, indications for the procedure, conscious sedation, and examination times-both insertion time and withdrawal time. The groups did not differ in the number of patients with all polyps, adenomas, or hyperplastic polyps. In the patients with adenomas, however, there was a significant difference in the detection rate for the patients with small adenomas less than 5 mm in size (P = 0.006).

CONCLUSIONS: Colonoscopy with the CVC mode identified more patients with small colorectal adenomas than conventional white-light colonoscopy. Therefore, CVC might be a supplementary tool aiding the colonoscopist in the detection of small adenomas; however, further studies will need to demonstrate whether these results are reproducible across patients in varied clinical settings.