What is an MRA test?
Magnetic resonance angiography (MRA) is an imaging test that shows your blood vessels and blood flow. An MRA can detect narrowing or blockages in your arteries in a noninvasive way.
You can have a non-enhanced MRA or a contrast-enhanced MRA. Images can be two-dimensional or three-dimensional.
Magnetic resonance angiography vs. CT angiography
Both of these are noninvasive imaging methods providers can use to see your blood vessels. However, a CT (computed tomography) angiogram is faster than an MRA. Also, they use different kinds of contrast materials. A CT angiogram exposes you to radiation during the scan. An MRA doesn’t use radiation.
What is the difference between an MRI and an MRA?
An MRA is a type of MRI. They use the same magnetic resonance imaging machine. An MRA uses an MRI to create images of your blood vessels. Also, a provider can use IV contrast to enhance imaging of your arterial system. An MRI can make images of your blood vessels, organs or even your whole body.
When would an MRA be needed?
Your healthcare provider can use MRA testing to diagnose a problem, such as a narrow artery. Also, they can use the information from an MRA scan to plan a surgery or check out an artery for a bypass graft.
They can use a magnetic resonance angiogram to look at your:
- Peripheral arteries.
- Carotid arteries.
- Renal (kidney) arteries.
- Pulmonary (lung) arteries.
- Coronary (heart) arteries.
- Arteries of your whole body if you have vasculitis or atherosclerosis.
Your provider can use an MRA test to diagnose multiple conditions, including:
- Aortic dissection.
- Pulmonary embolism (blood clot in your lung).
- Aneurysm (stretched out artery wall).
- Deep vein thrombosis (DVT).
- Congenital (since birth) heart disease.
- Arteriovenous malformation.
- Artery stenosis (narrowing).
Who performs an MRA?
An MRI technologist performs an MRA. They’ll make sure you’re in the right position for the required image. They’ll also explain the procedure, operate the MRI machine, give you the contrast in an IV and communicate with you during your MRA scan.
How does an MRA test work?
An MRA uses a strong magnetic field and radio waves to create images. Your provider can see these images on a computer. Unlike an X-ray, an MRA doesn’t use radiation. It gets information from energy your body gives off in a magnetic field.
Can MRA be done without contrast?
Yes, it can. This is called a non-enhanced or non-contrast MRA.
How long does an MRA scan take?
An MRA test can take 20 to 60 minutes. However, it takes a few minutes to put in an IV and get into position in the machine.
How do I prepare for an MRA?
Your provider will ask you questions to make sure you don’t have any metal in your body that could be a hazard during an MRA. This could be a medical device or a foreign object from an accident.
Some devices are safe to use in an MRI. Others aren’t. Your provider can check to see if it’s safe for you to have an MRI. Show them your medical device card if you have one.
If you get uncomfortable in tight spaces, ask your provider for a sedative that you can take before your MRA scan.
Tell your provider if you’re pregnant or breastfeeding (chestfeeding). Also, tell them about any health issues, allergies or surgeries you’ve had. If you have kidney or liver disease, your provider may not be able to use contrast for your scan.
Follow your provider’s instructions for eating, drinking and taking medicine before your MRA test.
What to expect on the day of an MRA
Wear comfortable clothes that don’t have metal in or on them. You can change into hospital clothing that doesn’t have zippers or any other metal.
Leave your watch, wallet and jewelry at home or put them in a hospital locker. An MRI can damage credit cards and send metals flying.
What happens during an MRA?
During an MRA, your provider will:
- Have you lie on a table that slides into and out of the MRI machine.
- Put headphones or earplugs on you to soften the machine’s loud noises.
- Remind you to lie still during the scan. Moving can cause distorted images.
- Give you a small ball to hold and squeeze if you need to contact the MRI operator. They can talk with and see you from an adjoining room.
- Press a button to slide the table you’re on into the middle of a large, round device with a hole in the middle.
- Start the MRI machine and start scanning.
- Possibly inject a contrast agent (dye) into your IV. This may give you a metal taste in your mouth for a short time.
- Take more images.
- Press a button to move the table you’re on out of the machine.
- Take out your IV.
What to expect after an MRA test
If you took a sedative to relax, you’ll need someone to drive you home.
If you didn’t take a sedative, you can drive yourself and go back to work or other activities right away.
What are the risks of an MRA test?
MRA testing is noninvasive and painless. You may feel a pinch when they put the IV in your arm.
Some people can have side effects from the contrast (dye), such as a headache, upset stomach or allergic reaction. This is rare.
People who have kidney failure are at risk of a rare condition called nephrogenic systemic fibrosis. The contrast agent can cause this condition, and it can be life-threatening.
Are MRA scans safe?
Yes, an MRA is safe. It doesn’t use radiation. An MRA doesn’t put anything into your body other than a contrast dye. People who are at risk of problems from the dye can have the scan without it.
Results and Follow-Up
What type of results do you get and what do the results mean?
Your provider will tell you if you have an issue in your blood vessels or other area they were examining. Based on your symptoms, they may have been looking for a certain condition. An MRA can confirm that you have a condition and show how severe it is.
When should I know the results of an MRA test?
It will most likely take a few days for a radiologist to review your MRA scan and send the results to your provider.
When should I call my doctor?
Contact your provider if you have a reaction to the contrast agent or if you haven’t received results a week after your MRA test.
A note from Cleveland Clinic
An MRA gives your healthcare provider valuable information about your body. This helps them make a diagnosis so you can get the care you need. An MRI machine can appear large and intimidating, but it’s harmless. You can wear headphones to soften the noise and take a sedative if the tight space makes you uncomfortable. The only thing you’ll feel going into your body is an IV if you’re receiving a contrast dye.
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