Flat polyps of the colon: detection with 16-MDCT colonography--preliminary results

This study evaluates the ability of contrast-enhanced, 16-MDCT colonography to display flat colonic lesions when a very narrow slice thickness (1 mm) is used.

Less than 50% of flat lesions in our population could be visualized by blinded and unblinded review. Before they could be visualized, flat lesions were 2 mm or greater in height and 7 mm or greater in diameter. Lesions with a height of 1 mm or less were not seen on CT colonography. Contrast enhancement, location on a haustral fold, and abnormal 2D and 3D morphology contributed to lesion conspicuity.