CAT and CT Scans

At Banner Health, our certified radiology team uses advanced medical imaging technology to give you accurate, detailed results. Whether your doctor orders a CT scan, CT angiography (CTA) or another test, you can expect clear answers and personalized care.

What is a CT scan and how does it work?

A computed tomography (CT) scan - sometimes called a CAT scan - is a type of X-ray that takes multiple images from different angles. These cross-sectional images are combined to give your doctor a complete view of your body’s internal organs, bones, muscles, blood vessels, soft tissues and nerves.

CT scans use ionizing radiation to create highly detailed CT images. Sometimes, contrast agents (also called contrast material) are used to make certain areas easier to see.

What is the difference between a CT scan and CAT scan?

You may hear both terms, but a CAT scan and a CT scan are the same test. “CAT” stands for “computed axial tomography,” while “CT” stands for “computed tomography.”

What conditions can a CT scan help diagnose?

CT scans help doctors evaluate many conditions. Your provider may order a CT scan to:

• Find tumors, infections or abscesses
• Detect internal injuries or bleeding
• Guide a biopsy or surgical procedure
• Check for signs of kidney disease or kidney function issues
• Evaluate the brain after a stroke or head injury
• Diagnose heart disease or monitor treatment progress
• Monitor cancer or assess how well treatments are working

CT scans are often combined with other imaging, like a PET scan, to provide a more complete picture of your health.

Learn more about PET scans at Banner Health.

What is a CT angiogram (CTA) and what does it show?

CT angiography (CTA) is a type of computed tomography that captures detailed images of your blood vessels. A contrast agent is injected into a vein to highlight arteries and veins.

CTA may be used to:

• Detect blood clots or blockages
• Find aneurysms or narrowed arteries
• Evaluate stroke risk or symptoms of heart disease
• Identify abnormal blood flow to or from tumors or organs
• Examine blood vessels in the brain, lungs or kidneys

For information on how CT angiography is used to examine the heart and coronary arteries, visit our angiogram page.

Where can I get a CT or CTA scan at Banner Health?

Most CT and CTA scans are outpatient procedures. They are available at Banner hospitals, clinics and select Banner Imaging locations.

Use our online tool to find a nearby location. Choose “CT/CT Angiography” under “exam type” to view available sites.

Need help scheduling? Our team is here to walk you through the process and answer any questions. Call your Banner provider or request an appointment online.

How should I prepare for a CT scan or CTA?

You’ll receive specific instructions based on the type of scan. In general, preparation may include:

• Removing metal objects: Do not wear jewelry or clothing with metal zippers or clips.
• Fasting: Some scans require you to avoid eating or drinking for a few hours.
• Drinking fluids or oral contrast: For abdominal or pelvic scans, you may be asked to drink water or oral contrast such as barium.
• Receiving a contrast agent: If your scan requires an injection of contrast material, let your doctor know if you’ve ever had allergic reactions to contrast before.

What should I expect during a CT scan or CTA?

CT scans and CTAs are quick and painless. You'll lie on a motorized table that passes through a CT scanner. To ensure clear images, you’ll be asked to stay very still and may be asked to hold your breath briefly.

If you’re having a CTA, a contrast agent will be injected through an IV in your arm. Some people notice a warm feeling or a metallic taste, which goes away quickly.

Most scans are completed within 5 to 30 minutes.

Are there risks or side effects from a CT scan or CTA?

CT scans use ionizing radiation, but the radiation dose is carefully managed to be as low as possible. CT scans are not usually recommended during pregnancy.

Side effects from contrast material are rare. Some people experience mild allergic reactions like nausea or flushing. Serious reactions are uncommon, but it’s important to share any allergies or concerns with your provider before your test.

Your care team will monitor you throughout the procedure to ensure your safety and comfort.

Why choose Banner Health for your CT or CTA scan?

With Banner’s advanced imaging tools and expert radiologists, you get fast, accurate results that support better decisions about your care. We offer a wide range of medical imaging services - including CT scans, CT angiography, and PET/CT - at comfortable, convenient locations across the communities we serve.

Don’t wait to get the answers you need. Schedule your CT scan or CTA today and take the next step toward better health.

Frequently asked questions about CT scans and CTA

What is the difference between a CT scan and a CTA? 

A CT scan shows your internal organs, bones and soft tissues. A CT angiogram (CTA) highlights blood vessels using a contrast dye to check for blood clots or blockages.

Is a CT scan the same as a CAT scan?

Yes. The names are used interchangeably. “CAT scan” is an older term for computed axial tomography.

Does a CT scan use radiation?

Yes. CT scans use ionizing radiation to create detailed CT images. The radiation dose is kept low for your safety.

Can I eat before a CT scan?

Sometimes. Your doctor will let you know if you need to fast depending on the scan type.

What if I’ve had an allergic reaction to contrast before?

Let your doctor know. Mild allergic reactions to contrast agents are rare and manageable, but precautions may be taken.

Can pregnant people have a CT scan?

CT scans are usually not recommended during pregnancy due to the use of radiation. Always inform your care team if you're pregnant.