Virtual Colonoscopy (CT Colonography)

A virtual colonoscopy is a test that uses a CT scan to take pictures of your colon and rectum (your large intestine). This is done from outside of your body. You do not need general anesthesia (medication that puts you to sleep so that you will not remember the test). Virtual colonoscopy is used to find ulcers, polyps, and cancer. It can be used as a screening exam for colon cancer in people over the age of 45. It may also be called CT colonography.

How do I prepare for a virtual colonoscopy?

Your provider will give you instructions on how to prepare for the test. Often you will need to:

• Be on a clear liquid diet for 1 to 2 days before the test.
• Empty your colon by taking a laxative the night before the test.
• Drink contrast medium right before the scan to help your provider see your colon and rectum.
• Talk to your provider about all medications you take. You may need to stop taking or change the dose of some medications before your test.

How is this test done?

You will put on a hospital gown. You will lie on an exam table on your side with your knees pulled up towards your chest. A small tube will be placed into your rectum to fill your colon with air or carbon dioxide. You will then turn onto your back and the exam table will slide into the CT machine. Pictures will be taken while you are on your back and then again while lying on your side and/or on your stomach. You may have to hold your breath at certain times during the test. The test usually takes about 10-15 minutes.

What should I expect after my virtual colonoscopy?

Unless your provider tells you otherwise, you can return to normal activities and a normal diet after the test. You may feel bloated and may pass more gas than normal as your body gets rid of the gas that was put into your colon before the test.

How will I get the results of my virtual colonoscopy?

After the test, your provider will talk to you about the findings. If they see polyps or tissue that does not look normal, they may recommend more testing, such as a traditional colonoscopy. If all the findings are normal, your provider will likely ask you to repeat the test in 5 years.