What to Expect During a Breast MRI

If your doctor has recommended a breast MRI, you might be wondering what exactly you’re signing up for. Unlike a mammogram or ultrasound, breast MRI offers extremely detailed imaging, especially useful if you have dense breast tissue, a strong family history, or a recent abnormal finding. But it’s a very different experience. Here’s what you should know.

What Happens During a Breast MRI

A breast MRI uses strong magnetic fields and radio waves, not radiation, to create high-resolution images of the breast tissue. You’ll lie face down on a padded table with two openings for your breasts. The table slides into a large tube-shaped machine.

Most breast MRIs use IV contrast dye, usually a gadolinium-based agent, to help identify abnormal tissue. The dye is injected into a vein, often in your arm, mid-scan. It’s not painful, but you might feel a brief cool sensation.

The scan itself lasts about 30 to 45 minutes (or half this time if doing an abbreviated/fast MRI), and during this time you’ll need to stay very still. The machine is loud, producing repetitive knocking sounds. You may be given earplugs or headphones to help block out the noise.

There’s no pain during the scan, but lying still in a face-down position can get uncomfortable, especially if you have back or neck issues. Communicate with the technician if you need to shift or pause.

How to Prepare for the Best Results

1. Schedule Around Your Cycle (if you’re premenopausal): For the clearest images, aim to schedule your MRI between day 7 and day 14 of your menstrual cycle. This is when hormonal breast changes are least likely to obscure the results.
2. Remove All Metal: Since MRI uses a strong magnet, you’ll need to remove everything metallic, including jewelry, piercings, hairpins, makeup with shimmer, and underwire bras. If you have a metal implant like a pacemaker, spinal hardware, or cochlear implant, let your doctor know in advance.
3. Eat Normally Unless Told Otherwise: Most breast MRIs don’t require fasting. But if you’re receiving contrast dye, some centers may ask you to avoid food for a few hours beforehand. Follow the specific instructions from your imaging center.
4. Know Your Kidney Function: Because gadolinium is cleared by the kidneys, your doctor may check your GFR (glomerular filtration rate) before the scan, especially if you have diabetes, high blood pressure, or a history of kidney disease.
5. Be Honest About Claustrophobia: The MRI machine is enclosed, which can trigger claustrophobia for some people. If you’re nervous, ask your doctor ahead of time about mild sedatives, open MRI options, or comfort aids like a mirror or music.
6. Let Them Know About Implants or Allergies: If you’ve had breast surgery, silicone implants, or a history of allergic reactions to contrast dye, let the imaging team know so they can adjust the protocol.

Bottom Line

Breast MRI is one of the best tools we have for catching breast cancer early in people who are at higher risk or have dense breast tissue. While the process might sound intense, with a little prep and the right expectations, it’s entirely manageable, and potentially life-saving.