Computed tomographic (CT) colonography, also called CTC or virtual colonoscopy (VC) is a powerful minimally invasive technique for colorectal cancer diagnosis.
For CT colonography, the technologist begins by positioning you on the CT exam table, usually lying flat on your back.
A very small, flexible tube will be passed two inches into your rectum to allow air to be gently pumped into the colon using a hand-held or electronic pump. The purpose of the gas is to inflate the colon as much as possible to eliminate any folds or wrinkles that might hide polyps from the physician’s view.
Once the scanning part is done, the tube is gently removed.