CT Colonoscopy

CT Colongraphy, also called Virtual Colonoscopy

A colonoscopy is used to screen for colorectal cancer—cancer of the colon or rectum. Colonoscopy is the gold standard for colorectal screening. If you can’t undergo a traditional colonoscopy, or chose not to, a virtual colonoscopy is another way to look for cancer or polyps (growths on the wall of the colon that could develop into cancer). A CT colonography uses special x-rays to look at the large intestines. It’s best at finding large polyps (bigger than 1 centimeter), which are the ones most likely to become cancerous.

Like a regular colonoscopy, a CT colonography requires that you clean your bowels thoroughly the day before your procedure. Your doctor will recommend the bowel cleansing prep he or she prefers. It’s important that you follow the directions carefully. If your bowel is not completely clean, you will have to repeat the procedure. A CT colonoscopy can also diagnose diverticulitis, a condition in which you develop small pouches on the wall of the colon.

What happens during a CT colonography?

You will lie on your left side with your knees drawn up towards your chest. Your radiologist will insert a small, flexible tube into your rectum and use air to inflate it so it’s easier to see on the x-ray. You’ll lie on your back while we move the table into the CT machine and take images of your lower abdomen. Then you’ll flip onto your stomach and we’ll take additional x-rays.

If your radiologist finds polyps or cancer, you’ll have to have a full colonoscopy to remove the polyps or to take a biopsy of the tumor. You may be able to have the colonoscopy the same day so you don’t have to repeat the bowel cleansing routine. If your CT colonoscopy is normal, we’ll ask you to come back in five years for your next one.