What is a breast MRI?
Breast MRI (magnetic resonance imaging) is an imaging study that uses powerful magnets, radio energy and computers to obtain highly-detailed images of your breast tissue. In addition, breast MRIs are used to perform cancer screenings in women at high risk for breast cancer, to gather more information about abnormal areas seen on a mammogram, or to manage treatment of breast cancer. MRIs can also be used to evaluate breast implants and to determine if they’ve ruptured or if they’re leaking. Like X-rays and CT scans, breast MRIs are painless and noninvasive, but unlike those other two imaging exams, MRIs do not use ionizing radiation.
The science behind your breast MRI
Your body contains a significant amount of water, and that water contains hydrogen atoms. Each hydrogen atom has a very tiny electrical “charge.” When those atoms are exposed to a powerful magnetic field like the field used in an MRI, they shift positions and “line up” in the same direction. As the MRI sends radio waves through your body, the atoms begin to change direction and pull against the magnetic field. When the radio waves are turned “off,” the particles resume their alignment, releasing tiny bursts of energy as they move. The MRI is so sensitive, it’s able to detect and measure these tiny energy outputs. Those measurements are used to create detailed images from different angles, providing a very clear “picture” of the inside of your body.
What’s more. because different types of tissue release energy at different rates, the radiologist can use the measurements to determine what type of tissue is being imaged, helping the doctor identify abnormal growths like tumors and cysts. Because they’re so precise and detailed, a breast MRI can provide your doctor with a lot more information than a mammogram or a breast ultrasound, making them a very powerful diagnostic tool. One more thing to know: The temporary directional shift in your hydrogen atoms is completely harmless and painless; you won't even know it's occurring, and there are no "side effects" afterward.)
What to expect during your breast MRI
During your breast MRI, you’ll lie face down on an exam table that’s designed to slide inside the tube-shaped MRI device. The table has openings to accommodate your breasts so they’re not compressed or “flattened” during the imaging. During the exam, a special contrast dye will be injected into your arm through an IV. The dye helps “highlight” the breast tissue, making it easier to identify abnormal areas. Often, an initial series of images is made before the dye is injected. (If you’re having a breast MRI to examine breast implants, dye usually isn’t used.)
During the exam, you’ll need to lie very still. The magnets used in an MRI can be loud, and you’ll hear a lot of clicking or thumping noises as the magnetic field and radio waves switch on and off. To help reduce the noise, you’ll be given a headset to wear. You’ll also be able to hear the technologist through the headphones, and you’ll be able to speak with them through an intercom system as well. The technologist will be in a separate room, using a computer to guide the exam. Because the MRI device is enclosed, some people may feel a little claustrophobic.
Most breast MRI exams last from 30 minutes to an hour. Once the exam is complete, you’ll be able to go home and resume your regular activities. Your MRI images will be reviewed by one of our board-certified radiologists and the final report will be forwarded to your doctor.