Magnetic Resonance Angiogram (MRA)

Magnetic resonance imaging (MRI) is a painless test that produces images of the inside of the body without using X-rays. During an MRI, strong magnets and radio waves work together in a magnetic field to form detailed images. MRI images may provide more details about a medical condition than X-rays, CT scans, and ultrasounds can provide.

A magnetic resonance angiogram (MRA) is an MRI done on your blood vessels. During an MRA, dye (contrast material or contrast dye) is injected into your body to make the images even clearer. MRA provides images of blood vessels and blood flow. It can be used to help diagnose and treat heart disorders, stroke, and blood vessel diseases.

Tell a health care provider about:

• Any surgeries you have had.
• Any metal you may have in your body. The magnet used in MRA can cause metal objects in your body to move. Metal can also make it hard to get high-quality images. Objects that may contain metal include:
  • Any joint replacement (prosthesis), such as an artificial knee or hip.
  • An implanted defibrillator, pacemaker, or neurostimulator.
  • A metallic ear implant (cochlear implant).
  • An artificial heart valve.
  • A metallic object in the eye socket.
  • Metal splinters.
  • Bullet fragments.
  • A port for delivering insulin or chemotherapy.
• Any tattoos you have. Some red dyes contain iron, which can cause problems with testing.
• Whether you are pregnant, may be pregnant, or are breastfeeding.
• Any fear of cramped spaces (claustrophobia). If this is a problem, it usually can be relieved with medicines.
• Any allergies you have.
• All medicines you are taking, including vitamins, herbs, eye drops, creams, and over-the-counter medicines.

What are the risks?

Generally, this is a safe test. However, problems can occur:

• If you have metal in your body, it may be affected by the magnet used during the test. If you have a metallic implant close to the area being tested, it may be hard to get high-quality images.
• Allergic reaction to the contrast dye is possible.
• If you are pregnant, you should avoid MRI tests, including MRA, during the first three months of pregnancy. MRI may have effects on an unborn baby.
• If you are breastfeeding, you may need to stop temporarily. Your breast milk may contain contrast material until the material naturally leaves your body.

What happens before the procedure?

• You will be asked to remove all metal, including:
  • Your watch, jewelry, and other metal objects.
  • Hearing aids.
  • Dentures.
  • Underwire bra.
  • Makeup. Certain kinds of makeup contain small amounts of metal.
  • Braces and fillings normally are not a problem.
• If you are breastfeeding, follow instructions from your health care provider about pumping before your test and stopping breastfeeding temporarily.

What happens during the procedure?

• You may be given earplugs or headphones to listen to music. The machine can be noisy.
• An IV will be inserted into one of your veins.
• Contrast material will be injected into your IV.
• You will lie down on a platform, similar to a long table.
• The platform will slide into a long tunnel that has magnets inside of it. When you are inside the tunnel, you will still be able to talk to your health care provider.
• You will be asked to lie very still while images are taken. Your health care provider will tell you when you can move. You may have to wait a few minutes to make sure that the images produced during the test are readable.
• When all images are produced, the platform will slide out of the tunnel.

The procedure may vary among health care providers and hospitals.

What happens after the procedure?

• You may return to your normal activities right away, or as told by your health care provider.
• Contrast material will leave your body through your urine within a day. You may be told to drink plenty of fluids to help flush the contrast material out of your system.
• If you are breastfeeding, do not breastfeed your child until your health care provider says that this is safe.
• It is up to you to get your test results. Ask your health care provider, or the department that is doing the test, when your results will be ready.

Summary

• Magnetic resonance imaging (MRI) is a painless test that produces detailed pictures of the inside of your body without using X-rays. Instead, strong magnets and radio waves work together in a magnetic field to form very detailed and sharp images.
• An MRI done on your blood vessels is called a magnetic resonance angiogram (MRA).
• An MRA produces detailed images of your blood vessels and blood flow. It can be used to help diagnose and treat heart disorders, stroke, and blood vessel diseases.
• Before the test, be sure to tell your health care provider about any metal you may have in your body.
• Talk with your health care provider about what your results mean.