Computed Tomography Angiogram (CT Angiogram)
What Affects the Test
You may not be able to have a CT
- You are pregnant. A CT angiogram isn't usually
done when a woman is pregnant, because there is a chance that the baby might be
harmed by the radiation.
- You have had an X-ray test that used
contrast material (such as a
barium enema) in the past 4 days. Barium shows up on
a CT angiogram and makes it hard to see the picture clearly. A CT angiogram
should be done before any tests that use barium.
- You are
allergic to the dye (contrast material) that is used during the
- You have kidney problems. The dye used during the test can
cause kidney damage in people whose kidneys don't work well.
take metformin (such as Glucophage) to control your
diabetes. The dye used during the test may cause
problems if you take this medicine.
- You are obese. A person who is
very overweight may not fit into a standard CT machine, or the X-ray table may
not be able to support his or her weight.
- You can't lie still
during the test.
- You have metal objects in your body, such as
surgical clips or metal in joint replacements. These objects may prevent a
clear view of the areas being examined.
What To Think About
Benefits and limitations
A CT angiogram is a less
invasive test than a standard angiogram. A standard angiogram involves
threading a thin tube called a catheter through an artery in your arm or leg up
to the area being studied. But with a CT angiogram, no tubes are put in your
body. To learn more, see the topic
If your doctor sees that one
or more of your blood vessels are narrowed or blocked, you may need a standard angiogram
anyway to double-check the abnormal results from the CT angiogram. This is more
likely to happen if your doctor is considering surgery to treat the
narrowing or blockage.
If your doctor finds a major blockage in one of your
blood vessels during a CT angiogram, you won't be able to get an immediate
angioplasty to clear the blockage. You will need a
separate procedure. But if you have a standard angiogram and the doctor finds a
major blockage, he or she can perform an angioplasty during the