What is a computed tomography/CT scan?

Also called a CT or CAT scan, it uses x-rays to make detailed pictures of anatomy inside of the body.

A CT scan can be used to study all parts of your body, such as the chest, abdomen, pelvis, head, neck, or an arm or leg. It can also take pictures of organs, blood vessels, bones, and the spinal cord.

How should I prepare for a CT exam?

  • On the day of your exam wear comfy, loose clothing.

  • Avoid wearing any clothing with snaps or zippers. Women having a chest CT should wear a sports bra.

  • For CT scans of the abdomen and pelvis you may not eat or drink 4 hours before your exam. You may take medicines with water if needed.

  • Women who are pregnant or think they could be pregnant should tell their doctor or x-ray tech prior to their CT.

What can I expect during this procedure?

Plan on being with us for at least 30 minutes. The time it takes will depend on the part of body being scanned.

During the test, you will lie flat on a table that is attached to the CT scanner. The table will move slowly into the CT scanner opening. The CT scanner sends x-rays through the area of the body being studied. The scanner creates thin pictures and saves them to a computer. The CT is a very useful tool that helps doctors look closely at certain areas.

CT scans are quick and painless. We will give you contrast before the exam to help the CT create better pictures. The type of contrast will depend on the body part being studied.

  • Oral Contrast– When taking pictures of the abdomen, we will ask you to drink contrast. This allows us to see the stomach, colon, and bowel better. Plan to drink at least 2 glasses of contrast for up to 1 hour before your exam.

  • IV Contrast – We may inject contrast through an IV to highlight the tissues in the body, blood vessels, or organs.

  • Enema – In rare cases we may need to give contrast by an enema.

During the Exam

  • You may feel flushed and have a metallic taste while getting IV contrast.

  • You may also feel as though you have urinated, though you didn’t.

Blood Tests

You may need blood tests before your scan. This blood test will check your kidney function. We will need to check your creatinine level if you:

  • Are over the age of 60.

  • Are taking medicine to treat diabetes.

  • Take metformin or drugs that contain metformin.

  • Have had chemotherapy or aminoglycoside in the last month.

  • Have a history of kidney disease. This includes tumor, surgery, solitary kidney, kidney transplant, or dialysis.

  • Are being treated for high blood pressure.

Radiology or your doctor will decide if you need a blood test. You may have your blood test before your CT scan or the same day. If you have it done before, please bring your results with you. You may have to come one hour early to do the blood test. We will let you know.

If you have diabetes and take any of the medicines listed below we may ask you to stop taking them for 48 hours (2 days) after your scan. Please talk with your doctor about other ways to control your blood sugar during this time. You may take these medicines before your scan but not after. Your doctor will tell you what to do.

  • Advandamet

  • ActoPlus Met

  • Fortamet

  • Glucovance

  • Glumetza

  • Glyburide

  • Janumet

  • Metaglip

  • Metformin

  • Riomet

Contrast Allergy

If you have had a previous reaction to contrast or iodine, please let your doctor know. Your doctor will need to give you 2 different medicines. You will need to prepare for 12 hours, and timing is very important. This medicine will prevent an allergic reaction. If you do not follow the directions for this medicine correctly you may have to reschedule your CT scan.

What can I expect after the scan is done?

Scan results will be sent to the doctor who ordered the scan for you. If you have not received a report within a couple of weeks, please call your doctor’s office. If you have questions or concerns before or after your CT scan, please call your doctor or clinic.

To find out more, see our website at patient.uwhealth.org search: CT scan.

Who to Call

To cancel or change your visit call: 608-263-XRAY (9729) ext. #2


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