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Computed Tomography (CT)

Computed tomography (CT) is a test that combines X-rays and computer scans. The result is a detailed picture that can show problems with soft tissues (such as the lining of your sinuses), organs (such as your kidneys or lungs), blood vessels, and bones.

Man lying on back on scanner table. Table is about to move into circular opening of CT scanner. Healthcare provider is preparing scanner.
During the test, relax and remain as still as you can.

Before your test

  • Be sure to tell your health care provider if you have ever had a reaction to contrast material ("X-ray dye"). If you have had a reaction, you may need to take medicine 12 hours before your scan, so be sure to tell your doctor ahead of time. 

  • Be sure to mention the medicines you take. Ask if it's OK to take them before the test. 

  • Follow any directions you’re given for not eating or drinking before the procedure. Your provider will give you instructions if required.

  • The length of the procedure may vary, depending on your condition and your provider's practices.

  • Arrive on time to check in.

  • When you arrive, you may be asked to change into a hospital gown. Remove all metal near the part of your body that will be scanned, including jewelry, eyeglasses, and dentures. Women may need to remove any bra that has metal underwire. 

Tell the technologist 

Be sure to tell the technologist if:

  • You have allergies or kidney problems

  • You take diabetes medicine

  • You are pregnant or think you may be

  • You ate or drank anything before the test

During your test

  • You may be given contrast through an intravenous (IV) line or by injection.

  • You will lie on a table. The table slides into the CT scanner.

  • The technologist will ask you to hold your breath for a few seconds during your scan.

After your test

  • You can go back to your normal diet and activities right away. Any contrast will pass naturally through your body within a day.

  • Before leaving, you may need to wait briefly while your images are being reviewed. Your doctor will discuss the test results with you during a follow-up appointment or over the phone.

  • Your next appointment is:__________________

Online Medical Reviewer: Dozier, Tennille, RN, BSN, RDMS
Online Medical Reviewer: MMI board-certified, academically affiliated clinician
Online Medical Reviewer: Pierce-Smith, Daphne, RN, MSN, CCRC
Last Review Date: 12/28/2013
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