CRDAMC Homepage | CRDAMC Library Phone #: (254) 288-8366 | CRDAMC Library Fax #: (254) 288-8368

Search Health Library

CT Colonography

(Computed Tomography Colonography; Virtual Colonoscopy)

Definition

CT colonography is a radiology test that looks at the colon (large intestine). It is one of many options for colon cancer screening.

Reasons for Test    TOP

This test is used to look for polyps or cancers of the colon.

Colon Polyps

Nucleus Image
Copyright © Nucleus Medical Media, Inc.

Possible Complications    TOP

CT colonography is safe. It can be used if you are too sick to have other forms of colon cancer screening.

In some cases, a contrast material is used. One complication may be an allergic reaction to the contrast.

What to Expect    TOP

Prior to Test

  • Do not eat for 8-12 hours prior to the test.
  • A bowel cleansing will be done with a laxative. The goal of the cleansing is to rid your colon of all stool. The laxative will cause you to have many bowel movements over several hours.
  • If you have diabetes, talk to your doctor about adjusting your medications.

Description of the Test

You will be positioned on your back on a movable x-ray table. Just before the test, a small tube will be inserted into your rectum. Air will be gently pumped through this tube. The table will move slowly though the donut-shaped CT scanner. While this is happening, you will need to lie very still. You will be asked to hold your breath during the scan. The scanning test will then be repeated with you lying on your stomach.

After Test    TOP

You will be able to leave after the test is done. You can resume your normal diet and activities.

How Long Will It Take?    TOP

30-40 minutes

Will It Hurt?    TOP

You may feel cramping and bloating. You may feel the urge to have a bowel movement.

Results    TOP

An specialist will review the images. If something abnormal is seen, your doctor may suggest a colonoscopy.

Call Your Doctor    TOP

It is important to monitor your recovery. Alert your doctor to any problems. If any of the following occur, call your doctor:

  • Nausea
  • Itching
  • Difficulty breathing

If you think you have an emergency, call for emergency medical services right away.

RESOURCES:

American College of Gastroenterology
http://gi.org
National Institute of Diabetes and Digestive and Kidney Diseases
https://www.niddk.nih.gov

CANADIAN RESOURCES:

Canadian Association of Gastroenterology
https://www.cag-acg.org
Canadian Cancer Society
http://www.cancer.ca

References:

CT colonography. Radiology Info—American College of Radiology website. Available at: https://www.radiologyinfo.org/en/info.cfm?pg=ct_colo. Updated March 17, 2016. Accessed October 3, 2017.
Fletcher RH. Colorectal cancer screening on stronger footing. NEJM. 2008;359(12):1285-1287.
Johnson CD, Chen MH, Toledano AY, et al. Accuracy of CT colonography for detection of large adenomas and cancers. NEJM. 2008;359(12): 1207-1217.
Mulhall P, Veerappan GR, Jackson JL. Meta-analysis: computed tomographic colonography. Ann Intern Med. 2005;142(8):635-650.
Yee J. Screening CT colonography. Radiol Clin North Am. 2004;42(4):757-766.
Last reviewed September 2017 by EBSCO Medical Review Board Daus Mahnke, MD
Last Updated: 9/17/2014

EBSCO Information Services is fully accredited by URAC. URAC is an independent, nonprofit health care accrediting organization dedicated to promoting health care quality through accreditation, certification and commendation.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

To send comments or feedback to our Editorial Team regarding the content please email us at healthlibrarysupport@ebsco.com. Our Health Library Support team will respond to your email request within 2 business days.

Health Library: Editorial Policy | Privacy Policy | Terms and Conditions | Support
36000 Darnall Loop Fort Hood, Texas 76544-4752 | Phone: (254) 288-8000