A CT Colonography, or virtual colonoscopy, is a safe, effective, and minimally invasive imaging scan used to screen patients for colorectal cancer. This screening is used as an alternative to a standard colonoscopy, but can also detect unexpected medical problems outside of the colon.
A CT Colonography uses x-ray equipment to examine the large intestine for cancer and growths, called polyps.
Prior to the exam, the physician may restrict the patient to clear fluids and provide prep instructions to clear the bowels. Patients will be instructed not to eat or drink anything for a few hours prior to the procedure.
During the exam, a small, flexible tube is inserted a short distance into the rectum to inflate the colon with air while CT images of the colon and the rectum are taken.
Two scans are performed: one with the patient lying on his or her back and a second lying on his or her stomach or side. Each scan takes about 10 seconds.
After the exam, the patient can continue daily activities normally.
Virtual colonoscopy is comparable in accuracy to a standard colonoscopy for patients at average risk for colorectal cancer. This scan is typically used as an alternative for those who cannot physically undergo a standard colonoscopy as determined by his or her physician. Those at high risk for the disease due to a family history or other factors should have a standard colonoscopy.