What is Breast MRI?

Breast MRI (magnetic resonance imaging) is an imaging test that can find some breast cancers that wouldn’t be detected on a mammogram, particularly in women with dense breast tissue. 

People who already have a breast cancer diagnosis may get an MRI to check how far cancer has spread. Breast MRIs are also used to see whether breast implants have ruptured.

Breast MRI uses magnets and radio waves to produce detailed 3D images of the breast tissue.

Regardless of the type of breast MRI you get, you can expect to follow the same steps:

1. You’ll remove your clothing and change into pants that don’t have any zippers or other metal and a gown that opens in the front. You’ll also be asked to remove anything metal you may be wearing. 

2. A contrast solution (dye) will be injected into a vein in your arm or hand through an IV (intravenous line).

3. During the test, you’ll lie face down on your stomach on a padded platform that has cushioned openings for your breasts. Your breasts hang down through the openings in the platform and are not compressed. Each opening is surrounded by a breast coil, which is a signal receiver that detects magnetic signals from the MRI machine.

4. The platform slides into the center of the large, tube-shaped MRI machine. You’ll need to stay very still. You won’t feel anything, but you’ll hear loud noises from the MRI machine. Earplugs or headphones will usually be provided to block the sound. You may be able to listen to music on the headphones if you’d like.

5. The technologist or radiologist will be monitoring you from another room. They may ask you to hold your breath for a few seconds or keep extra still during some parts of the test. You’ll be able to talk to them through a special microphone.

6. The test will take a total of about 25 to 45 minutes to complete if you’re getting a conventional breast MRI or about 10 to 20 minutes if you’re getting a fast or abbreviated breast MRI.

There are several reasons why your doctor might recommend a breast MRI for you.

Informing breast cancer treatment

To find out the extent of breast cancer: After a breast cancer diagnosis, breast MRI may be used to help determine the size and location of the tumor and check for any additional tumors in the breasts. Breast MRI is also used to determine if cancer has spread to the chest wall or to lymph nodes in the armpit.

To find out how well chemotherapy is working: When chemotherapy is given before breast cancer surgery (this approach is known as “neoadjuvant chemotherapy”), breast MRIs may be used to see how well the chemotherapy is working to shrink the tumor. One breast MRI test may be done at the start of chemotherapy and one may be done in the middle or at the end of chemotherapy treatment.

Breast cancer screening

To screen for breast cancer in people with certain risk factors: If you’re at high risk for breast cancer (you have a lifetime risk of 20% or more) or you have extremely dense breast tissue, your doctor may recommend that you get a breast MRI each year in addition to your annual mammogram. They might also recommend that you get supplemental screening with a breast ultrasound instead of or in addition to breast MRI.

You can find out your personal risk for breast cancer by asking your doctor to do a risk assessment. Your doctor will factor in your breast density, which can be found on your mammogram report. When breast MRI is used for breast cancer screening, it’s almost always used in addition to — not instead of — a mammogram. That’s because each test can sometimes find cancers that the other would miss. 

To gather more information about something that looks unusual in the breast: Doctors sometimes use breast MRI to further examine an area of suspicion seen on a mammogram or ultrasound and help decide if a biopsy is needed.

Biopsy

To guide the needle during a biopsy procedure: A biopsy is the only way to know for sure if a suspicious area of breast tissue contains cancer. Breast MRI may be used to guide the positioning of the needle during a biopsy of the breast. (Note: Doctors don't always use the same type of breast imaging for the biopsy that was used to initially detect the suspicious area in the breast. For example, sometimes a suspicious area is detected using breast MRI and ultrasound is used to guide the biopsy needle.)  

Monitoring breast implants

To check if silicone gel-filled breast implants have ruptured: If you have silicone gel-filled breast implants, the U.S. Food and Drug Administration (FDA) recommends periodic imaging with breast ultrasound or breast MRI to check if the implants have ruptured. The first MRI or ultrasound should take place five to six years after the initial implant surgery and then every two to three years after that. 

Breast MRI is also recommended for those who have symptoms of silicone gel-filled implant rupture or who have had a breast ultrasound that didn’t clearly show whether or not the implants have ruptured. Contrast dye is not used during the test if the only reason you’re getting the MRI is to check for implant rupture.

People with dense breast tissue or other factors that put them at higher-than-average risk of breast cancer may use fast (or abbreviated) breast MRI to screen for breast cancer. Fast breast MRI captures fewer images than conventional breast MRI and takes a fraction of the time. It’s considered as effective as conventional breast MRI for screening for breast cancer. As with conventional MRI, when it’s used for screening it’s always in addition to (not instead of) annual mammograms. Fast breast MRI is not used in people who have symptoms of breast cancer and/or a history of breast cancer. Fast breast MRI is not yet available at all breast imaging centers, and it’s usually not covered by insurance.

Depending on where you live, you may be able to get a breast MRI at a local hospital radiology department, breast center, or outpatient imaging center. Usually, the doctor who is recommending that you have a breast MRI will suggest a center to have the test done.

When you schedule your breast MRI, the imaging center staff will tell you how to prepare. They should let you know whether you should eat, drink, and take your medications as usual on the day of the test.

Make sure you have an order (prescription) from your doctor for the breast MRI and that you’re providing the imaging center with the names and contact info for all the doctors who should receive your test results.

In some situations, you may not be able to have an MRI. These include if you have an implanted medical device or other metal objects in your body (including some breast tissue expanders) or if you have liver or kidney problems that could cause complications from the contrast solution. Also, breast MRIs with contrast solution usually aren't used during pregnancy due to concerns that the contrast dye might pose risks to the fetus.

In the past, women were sometimes advised to stop breastfeeding temporarily when they got a breast MRI. More recent studies suggest this may not be necessary because the amount of contrast dye that is excreted into the breast milk is so small that it doesn’t pose a risk to the baby. If you’re breastfeeding, ask your doctor if they recommend that you pump and discard your milk right after the test.

If you’re scared of enclosed spaces (claustrophobia), have anxiety, or have trouble lying still on your chest, you may want to ask your doctor ahead of time for prescription medication (such as anti-anxiety medication) that could help you feel more comfortable during the test. You could also look into facilities that have a traditional breast MRI machine with a larger opening (a “wide bore” MRI scanner).

Also, if you’ve ever had an allergic reaction to the injectable contrast solution that’s used during most breast MRIs, make sure you mention this to your doctor and the imaging center staff. Your doctor can prescribe medication that you take before you receive the injectable solution that will prevent an allergic reaction. 

A radiologist (a doctor who specializes in interpreting medical images) will analyze the images from your breast MRI. The radiologist will send the images and a written report about the results to the doctor who ordered the test. In most cases, the doctor who ordered the test will be the one who shares and discusses the results and any next steps with you. But sometimes it will be the radiologist.

You should also receive the written report through a patient portal. If you want a copy of the images, you can request to have them given to you on a CD.

Radiologists use a system called the Breast Imaging Report and Database System, or BI-RADS, to report what they find on a breast MRI, mammogram, or an ultrasound. You may not see these scores, but the written report of your breast MRI results that is sent to the doctor always includes them.

Compared with mammograms and with breast ultrasound, breast MRI is a more expensive test to perform, and it’s not available at as many healthcare facilities.

It’s a good idea to contact your health insurance company before you have a breast MRI and ask if the test is covered and if you’ll have any out-of-pocket costs (such as a deductible, co-pay, or co-insurance). Also, ask if the insurance company needs to authorize the test beforehand for it to be covered. (Most insurance companies require this for breast MRIs). If your insurance company initially says they won’t cover your breast MRI, you and your doctor may want to make the case for them to cover it.

​​Insurance coverage of conventional breast MRI varies a lot. If you have to pay out-of-pocket, costs might range from about $300 to more than $1,000.

Fast (or abbreviated) breast MRI is usually not covered by insurance and typically costs $300 to $500. Sometimes people opt to get a fast breast MRI as a screening test as a way to save on out-of-pocket costs when their insurance won’t fully cover a conventional breast MRI.

DenseBreast-info.org is a good resource for finding out if the state you live in has any laws requiring insurance companies to cover supplemental breast cancer screening tests.

If your income is low and you are uninsured or underinsured, you may qualify for free or low-cost breast MRIs for screening or diagnosis through the Centers for Disease Control and Prevention (CDC)’s National Breast and Cervical Cancer Early Detection Program.