Computed Tomography Angiography (CTA)

CTA can make 3D images, such as the carotid arteries shown here.

Computed tomography angiography (CTA) is an imaging test. It uses X-rays and computer technology to make detailed pictures of your arteries. Before the test, an X-ray dye (contrast medium) is injected into your vein. The dye makes it easier to see your blood vessels on the X-ray. Pictures are then taken with the CT scanner. A computer turns the images into 2-D and 3-D pictures.

Why CTA is done

CTA may be used to:

• Check arteries in your belly, neck, lungs, pelvis, kidneys, or brain.

• Look for a ballooning of the blood vessel wall (aneurysm) or a tear (dissection).

• Check if a tube (stent) used to keep an artery open is working well.

• Find damage to your arteries due to injuries.

• Collect details on blood vessels that supply blood to tumors.

Getting ready for your test

Tell your health care provider if you:

• Have diabetes

• Have kidney disease

• Are allergic to X-ray dye or other medicines

• Are pregnant or think you may be pregnant

• Are taking any medicines, herbs, or supplements, including prescription drugs, street drugs, and over-the-counter medicines such as aspirin or ibuprofen  

You may be told not to eat or drink anything for a few hours before the CTA. Follow any other instructions from your health care provider.

During your test

• You will be asked to remove any hair clips, jewelry, false teeth, or other metal items that could show up on the X-ray.

• You will lie down on the scanning table. An IV line will be put in a vein in your arm or hand.

• The scanning table will be properly placed. The part of your body being checked will be inside the doughnut-shaped CT scanner.

• One image may be taken first to be sure you are in the proper position for the test.

• The IV will be hooked up to an automatic injection machine. This controls how often and how fast the X-ray dye is injected. The injection may continue during part of the exam.

• The dye will be put into your vein through the IV line. You may feel warmth through your body when the dye is injected.

• You can’t move while the X-rays are being taken. Pillows and foam pads may be used to help you stay still. You will be told to hold your breath for 10 to 25 seconds at a time.

• The whole procedure may take 10 to 25 minutes.

After your test

• Drink plenty of fluids to help flush the X-ray dye from your body.

• You may eat as soon as you want to.

All procedures have some risks. A CTA has some possible minor risks. These include:

• Problems due to the X-ray dye, such as an allergic reaction or kidney damage

• Skin damage from leaking X-ray dye near where the IV was put in