Medical questions & health advice by board certified doctors

"What is a rectal contrast?"

ZocdocAnswersWhat is a rectal contrast?


My doctor ordered a CT scan that includes something called a rectal contrast. What does this mean? What is involved with this kind of a test?


A CT scan (also known as "CAT scan") is an imaging test which takes serial x-ray images of your body and reconstructs it using computer software to create an image of internal organs and structures. This is a great test, but there are several things that can make it even better. Giving contrast highlights specific organs and/or structures to give a better view or image of the organ in question. IV contrast is given to look at blood vessels and organs that are highly vascularized (for example: the liver). Oral contrast is given to look for bowel obstructions. Rectal contrast is a liquid which is given by way of injecting the contrast into the rectum to highlight the colorectal anatomy. This is administered similar to how an enema would be given. Usually this is done to give better visualization of the lower GI tract (specifically the colon and the rectum). Sometimes giving rectal contrast can detect, strictures, masses, or leaks. After the contrast is administered, the CT scan can be performed. What this entails is for the patient to lay on a bed which then moves through a CT scanner gate. The entire test usually only takes 3-4 mintues, depending on how much of your body is being scanned. I recommend that you speak to your physician, who can give you more information regarding details of your testing.

Zocdoc Answers is for general informational purposes only and is not a substitute for professional medical advice. If you think you may have a medical emergency, call your doctor (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Medical professionals who provide responses to health-related questions are intended third party beneficiaries with certain rights under Zocdoc’s Terms of Service.