Virlual colonoscopy for screening: accurate, acceptable, but affordable?

Virtual colonoscopy for colorectal cancer screening sounds attractive: non-invasive, no sedation, and no collection of stool. However, a full bowel preparation is needed and so far its sensitivity and specificity for lesions measuring less than 10 mm diameter have suggested it is not accurate enough to be used for screening. This study involves 1233 average risk asymptomatic adults in three centres who underwent virtual colonoscopy followed by a some day conventional colonoscopy. Multidetector computed tomograph scans were used to generate fast high resolution images, and water soluble and barium contrast materials were used to tag residual fluid and stool.