CT angiography is a type of medical test that combines a CT scan with an injection of a special dye to produce pictures of blood vessels and tissues in a part of your body. The dye is injected through an intravenous (IV) line started in your arm or hand.
A computerized tomography scan, or CT scan, is a type of X-ray that uses a computer to make cross-sectional images of your body. The dye injected to perform CT angiography is called a contrast material because it "lights up" blood vessels and tissues that are being studied.
You may need this medical test if you have an abnormality that involves the blood vessels of your brain, heart, lungs, kidneys, or other parts of your body. Healthcare providers may use the information from this test to learn more about your condition and to decide the best way to treat you. Some reasons to have a CT angiogram include:
Information from CT angiography may help prevent a stroke or a heart attack. This type of test may also help your healthcare provider plan cancer treatment or prepare you for a kidney transplant. Your healthcare provider may have other reasons for ordering this test.
There is always a slight risk for cancer from repeated exposure to radiation, but the benefits of getting an accurate diagnosis generally outweigh the risks. The amount of radiation used during CT angiography is considered minimal, so the risk for radiation exposure is low. No radiation remains in your body after a CT scan.
Other risks include:
Angiography contrast material can damage your kidneys, so you may not be able to have this test if you have severe kidney disease or diabetes.
If you are breastfeeding, you will need to wait for 24 hours after this test before nursing your baby. If you are pregnant or suspect that you may be pregnant, you should notify your healthcare provider or radiology technician.
There may be other risks, depending on your specific medical condition. Be sure to discuss any concerns with your healthcare provider or radiology technician before the test.
Tell your healthcare provider and your radiology technician about any medicines you take, including herbal supplements and other over-the-counter medicines. Also let them know about any medical conditions you may have, such as heart disease, diabetes, asthma, thyroid, or kidney disease, and any recent illness.
You may be asked to sign an informed consent that describes the risks and benefits of this test. You should discuss the risks and benefits with the healthcare provider or the radiology technician. Other preparations include:
Based on your medical condition, your healthcare provider may request other specific preparation.
You may have this test done at the hospital or at another outpatient facility. The CT scanner is a large machine with a tunnel that the examining table passes in and out of. Tests may vary depending on your condition and your healthcare provider's practices.
Here is what may happen during the test:
After the test is completed, you will have your IV removed. In most cases, you can return to all your normal activities at home. You may be given some additional instructions after the test, depending on your particular situation.