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About Your Computed Tomography (CT) Exam

What is a CT scan?

A computed tomography (CT or CAT) scan lets doctors see inside your body. It uses a combination of X-rays and software to create images of your organs, bones, and other soft tissues. Sometimes contrast is used to see even more clearly.

A CT scan is painless and can take anywhere between 1 to 30 minutes. There is some exposure to radiation, but it's minimal. If you have concerns, please call your doctor to learn more.

How do I prepare?

Specific prep steps for this scan:

  • We'll message you detailed instructions for your specific scan. So, keep an eye out for new texts/emails.
  • Please check patient gateway for arrival time and required forms for your
  • If you have a known allergy to x-ray dye (contrast) please inform your doctor.
  • Wear loose, comfortable clothing. We may ask you to change into a hospital gown.
  • Leave jewelry and valuables at home.
  • Children and family are not allowed in the exam room. Please make childcare arrangements before your appointment.
What should I expect?
  • Once you arrive, you may need to fill out some forms about your medical history, allergies, and current medications.
  • If you will be taking oral contrast before your scan, you'll need to drink it and then wait for it to absorb, this may take over an hour.
  • The technologist will escort you back to the exam room and will help you get situated on the CT table.
  • The CT scanner is a large, donut-shaped machine. You will lay on a narrow examination table that slides in and out of the opening, which will rotate during the scan.
  • The technologist will be able to hear and talk to you from their workstation. Speak up if you get anxious, have questions, or experience any pain.

Patient lying on CT scanner

What’s the difference between an MRI & CT?

CTs are relatively quick scans and do not require you to enter a tunnel. The CT is open on both sides and while you may go through the opening, you are not encased entirely by the machine. The CT machines are not as loud as the MRI machines and do not require headphones or earplugs.

What is contrast?

Some exams use contrast either oral, IV, or both. Contrast helps the Radiologist see more clearly. 

Oral contrast takes time to absorb into the body (which is why you may have to come an hour before your scan).

IV contrast is administered on the scan table. You might feel warm after it’s injected and even feel like you need to urinate. That’s normal, and passes quickly. 

If you have had a previous contrast reaction in the past, you might need to be premedicated before your exam. Call your referring physician if you aren’t sure about an allergy to contrast.

What happens during the scan?

The technologist will assist you onto the CT exam table. They may use straps and pillows to adjust your position.

The technologist will go back to their workstation behind a clear window. They will be able to hear you and see you.

Then, the table will move slowly through the machine during the scan. Depending on the type of CT scan, the machine will make several passes back and forth. The exam may take anywhere from 1 to 30 minutes.

You may be told how to breathe - hold your breath, breathe normally, breathe out during the scanning.

After the scan is done, you will be asked to wait until the technologist reviews the images.

Are there any risks?

The amount of radiation delivered during the scan is very minimal.

CT scans are generally not recommended for pregnant women unless necessary. If you are pregnant, please inform your physician.

If you have had a previous contrast reaction in the past, you might need to be premedicated before your exam. Call your referring physician if you aren’t sure about an allergy to contrast.

Let your physician know if you have any concerns. They’ll be happy to help explain the risks, benefits, and if there are other options.

When will I get my results?

Once the scan is done, the images are sent over to a Radiologist. The Radiologist will read the images and send a report over to your referring physician. This can take a few days.

Please contact your referring physician to review your results and discuss next steps.

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