[Virtual colonoscopy]

Colorectal cancer is a leading cause of cancer death in the western world. Virtual colonoscopy is a new method for 2-D and 3-D imaging of the colon, using a multislice helical CT technology. This method has already demonstrated excellent results in polyp and cancer detection, having similar accuracy to endoscopic colonoscopy in the detection of polyps above 6 mm in size. The major application of this novel technique is in diagnosing cases where conventional colonoscopy fails to demonstrate the entire colon due to technical problems. The second important application is to investigate the colon proximal to an obstructing tumor, where both barium enema and colonoscopy cannot overcome the obstruction. The possibility of widespread application remains in evaluating the use of virtual colonoscopy in a purely screening population. Further developments, including stool tagging, computer aided detection of polyps and faster scanners will contribute to accuracy and patient compliance with widespread use of virtual colonoscopy. This examination may dramatically improve population participation in screening programs and play a major role in minimizing the impact of colorectal cancer.