Unlike other colon cancer screening tests, this imaging test doesn't use a scope to examine your colon. Learn how it works and what to expect.
Virtual colonoscopy is a less invasive way to check for cancer of the large intestine. Virtual colonoscopy is also known as screening CT colonography.
Unlike the usual or traditional colonoscopy, which needs a scope to be put into your rectum and advanced through your colon, virtual colonoscopy uses a CT scan to take hundreds of cross-sectional pictures of your belly organs. The pictures are then added together to provide a complete view of the inside of the colon and rectum. Virtual colonoscopy needs a similar bowel cleaning as a usual colonoscopy.
Virtual colonoscopy is one way to check for colon cancer. Discuss your colon cancer screening choices with your health care provider to see if virtual colonoscopy is the right choice for you.
Virtual colonoscopy is used to check for colon cancer in people who are at least 45 years old.
Your health care provider may suggest a virtual colonoscopy if you:
You aren't able to have a virtual colonoscopy if you have:
Studies have shown that virtual colonoscopy finds large polys and cancer at about the same rate as usual colonoscopy.
Because virtual colonoscopy looks at the entire abdomen and pelvic area, many other diseases may be found. Problems unrelated to colon cancer such as irregularities in the kidneys, liver or pancreas can be detected. This may lead to more testing.
Virtual colonoscopy is generally safe. Risks include:
Not all health insurance providers pay for virtual colonoscopy for colon cancer screening. Check with your health insurance provider to see which tests are covered.
Before a virtual colonoscopy, you'll need to empty your colon. Any bowel movement, or stool, left in your colon may cloud the pictures taken during the exam.
To empty your colon, follow your health care provider's instructions carefully. You may be asked to:
You'll wear a gown but likely no other clothes. Medicine to put you to sleep usually isn't necessary, but you may be given medicine to relax your colon.
You'll begin the exam lying on your side on the exam table, usually with your knees drawn toward your chest. A nurse or technologist will place a small tube called a catheter inside your rectum. Through this catheter, your colon will be filled with air or carbon dioxide as you roll over on the table while keeping your spine straight. The air or gas helps create clear pictures and may cause a feeling of pressure in your stomach area.
For the next part of the exam, you'll lie on your back. The exam table will be moved into the CT machine, and your body will be scanned. Then you'll turn over to lie on your belly or your side and your body will be scanned again.
You may be asked to turn and hold some other positions as well as hold your breath at times.
A virtual colonoscopy typically takes about 15 minutes.
You can restart your usual activities after your virtual colonoscopy. You may feel bloated or pass gas for a few hours after the exam as you clear any remaining air or gas from your colon.
Your health care provider will go over the results of the colonoscopy and then share them with you.
Your test results may be: