Colorectal cancer is the 2nd-leading cause of cancer-related deaths. Although it is preventable in more than 90 percent of cases in which polyps are detected early, an estimated 80 to 85 percent of people avoid colon cancer screening, attributable partly to the discomfort of conventional optical colonoscopy. Unlike (traditional) optical colonoscopy, virtual colonoscopy requires no sedation because it is minimally invasive. This allows patients to resume their normal daily activities almost immediately after the exam.
While conventional colonoscopy takes two hours or more to perform, virtual colonoscopy can be completed within half an hour and is a far more comfortable procedure.
What to expect
The test requires the insertion of a small rectal tube, through which carbon dioxide is gently pumped to expand the folds of the colon. The process is not painful, but may cause the feeling of fullness and mild cramping, as if you need to pass gas.
At least two separate CT scans will be performed. During each scan, which takes about 10 seconds, you should remain as still as possible to produce the clearest images.
Since no sedation occurs during CT colonography, you will be able to resume normal activity immediately following your scan.
The entire procedure typically takes about 30 minutes.