
MRI-Guided Breast Biopsy

What Is an MRI-Guided Biopsy of the Breast?
Your physician may order an MRI for a more detailed look at breast tissues for prevention or diagnosis. Sometimes a breast MRI is performed as a preventative imaging scan in high-risk women with a strong family history of breast cancer. These women may undergo regular MRI imaging to look for subtle differences that may represent cancer, as a supplemental imaging scan in addition to mammograms.
A breast MRI can evaluate the extent of disease in patients with a recent breast cancer diagnosis. Contrast MRI imaging looks for additional breast cancers within either breast. It can also provide a detailed map for surgeons before surgery.
Radiologists specializing in women’s imaging look for subtle tissue changes in the breast, including vascular changes found by breast MRI. These changes may be as obvious as a rapidly enhancing mass or as subtle as a non-mass-like enhancement. The radiologist will recommend a biopsy if the test shows a suspicious MRI lesion.
How Do Breast Abnormalities Appear on an MRI?
MRI, magnetic resonance imaging, uses magnets and radio waves to produce detailed 3D imaging of the breast or other organs. A breast MRI helps to distinguish normal tissues from abnormal tissue. Signs that may indicate breast tissue changes can include:
- Masses
- Lumps
- Calcifications
- Abnormal tissue
We use contrast to show blood vessels and help identify any potentially cancerous breast tissue, which needs a blood supply to grow. On a breast MRI, the contrast tends to become more concentrated in areas of cancer growth. These areas may show up as white areas on a dark background.
A specialized radiologist with many years of training in women’s imaging and breast imaging interprets the MRI scan images to distinguish the different patterns of vascular uptake in the tissues called enhancement. Some patterns of enhancement in the breast are normal, while others may represent breast cancer. The background parenchymal enhancement (PBE) refers to the qualitative enhancement of fibro glandular tissue. A subtle MRI abnormality will be less evident in a breast with moderate background enhancement. In comparison, an abnormal finding will stand out better in a breast with minimal background enhancement.

Who’s Reading Your MRI?
At The Women’s Imaging Center, we perform thousands of MRIs. The more experience the facility has with breast MRIs, the better the images will be for interpretation. Our radiologists are experts at both reading breast MRIs and performing MRI-guided breast biopsies. The radiologists at The Women’s Imaging Center specialize in performing any or all modalities utilized in women’s radiology, including breast, gynecologic, abdominal, thyroid, pelvic, and endocrine bone density.
What to Expect With an MRI-Guided Breast Biopsy
There are a few things we ask you to do to prepare before your procedure.
- Before the scan, we will determine if the imaging service is best for you by taking a complete medical history. If there is any question about your kidney function, your ordering physician will order a blood test called "creatinine clearance."
- We may use a contrast dye called gadolinium. Please let us know if you have ever had a reaction to contrast dye (different from the dye used in a CT exam.) For most people, this is not an issue.
- We ask that you do not take medicines that can thin the blood unless you are directed to continue taking them by your referring physician. Some patients may have special reasons to stay on their blood thinners, such as a clotting disorder. Always listen to your referring clinician regarding those decisions. We advise against taking aspirin if you are solely on it for prevention reasons.
- Your technologist will place a small catheter called an IV in your arm. You will lie comfortably on your abdomen with your breasts gently suspended with the excess room. Your head will be near the end of the magnet so you can see out. Your forehead rests on a special pad like a massage table with a mirror so you can see all around you. The MRI we use features a large bore opening called an “Open Solution MRI.”
- The technologist will inject the contrast while you lie comfortably. You may feel a warm sensation for a few seconds during the injection.
The magnet makes a loud clunking sound, so the technologists will fit you with comfortable headphones, and you may choose to listen to music through the headphone that makes the magnet sound indistinct. Many patients actually find the exam soothing because of the music and may fall asleep. - It is important not to move quickly or jerk during the exam because this may cause irregularities in the images constituted from signals of the magnets.
- You will see several assistants to help with the procedure: the technologist, the radiologist, and a patient navigator.
- The technologist will obtain MRI images for targeting, and contrast dye will be injected to show the lesion.
- The radiologist will anesthetize the skin with a tiny numbing needle and use MRI guidance to see exactly where the abnormality is located in 3D space.
- Another special needle called a “probe” is inserted at the target site, more anesthetic is given through that probe, and a light vacuum is directed to the lesion. A clip is placed at the biopsy site so that we know exactly where the tissue sample originated. The sample is then delivered to the pathologist.
- We ask that you refrain from vigorous activities for one to two days after the procedure. If you are planning an active vacation to include swimming or similar active pursuits, consider postponing the biopsy until you return. Even though there will be only a tiny nick on the skin, we want to minimize the chance of soreness, infection, or bleeding at the site.
- You will likely experience slight bruising of the breast for a few days. Some women may complain of feeling a lump under the biopsy site for up to a week. When we take a tissue sample containing the calcifications out of the breast at a particular site, the body sends serum and blood to that area to help it heal.
- Infection is extremely rare, but if you have any redness at the site, any fevers or chills, we ask that you call us or return to The Women's Imaging Center for evaluation. Direct contact sensitivity from the tape on the skin can be common in some people. A tape sensitivity is associated with a local area that perfectly fits the tape's line. So if the tape is itchy or burning, remove it and wear a tight sports bra instead. Call your referring clinician or us if you have any concerns.
The results of your MRI-guided breast biopsy will be available in a few working days. The Women’s Imaging Center Patient Navigator and the radiologist correlate the results and coordinate any follow-up care or management indicated. Follow-up magnification images after the biopsy may be recommended even for benign biopsies. A contrast breast MRI can help with treatment planning if the biopsy proves to be cancer. We will work with your referring clinician to coordinate an individualized treatment plan with surgeons or oncologists to fit your particular needs.
MRI-Guided Breast Biopsy in Denver
Meet Our Specialists
Kelly McAleese, M.D.
Timothy Colt, M.D.
Barbara Jaegar, M.D.
John Lewin, M.D.

Frequently Asked Questions About MRI-Guided Breast Biopsy
An MRI-guided breast biopsy is a minimally invasive procedure that uses MRI technology to guide the biopsy needle to obtain tissue samples from suspicious areas in the breast. The radiologist removes small tissue samples to be sent off for testing.
If a patient has breast implants, we can use a special technique to safely perform the biopsy without damaging the implant. Typically, this involves using a needle that is longer than normal to reach the tissue sample through the implant.
Studies have shown that the cancer detection rate with MRI-guided biopsy ranges from 10-50%.
The main difference between an MRI-guided breast biopsy and a breast stereotactic biopsy is the type of imaging used to guide the procedure. MRI-guided biopsy uses MRI technology to locate the suspicious area, while stereotactic biopsy uses mammography or X-ray imaging. Both biopsies are minimally invasive procedures used to obtain tissue samples from the breast for further analysis.
Claustrophobia, “a fear of being in closed or narrow spaces,” is not uncommon. The MRI used at The Women’s Imaging Center has an especially wide bore (opening), so much that you can barely touch the sides with your outstretched arms. The MRI machine is also shorter than most at hospitals since we perform dedicated MRIs of specific female systems like breasts, pelvis, and abdomen. The Espirit MRI is also called an “Open MRI Solution” by the manufacturer Siemens. You will lie comfortably on your abdomen with your breasts gently suspended with the excess room. Your head will be near the end of the magnet so you can see out. Your forehead rests on a special pad like a massage table with a mirror so you can see all around you. You will be talking with the MRI technologist during the entire exam, and she can make any adjustments to make you more comfortable. The great majority of the time, no premedication is needed. However, if you feel you simply cannot perform the MRI without sedation, then our physicians or yours can write oral anxiety medications that you will have to pick up and coordinate with the timing of your MRI exam under our advice. If you need to take these medications, you will need a driver; we are not permitted to let you drive yourself if you have taken any medications that may make you drowsy.
Yes, we recommend that you talk with your insurance provider before your MRI or MRI-Guided biopsy is scheduled to determine your financial responsibility with them based on your particular insurance plan. We will also talk with an authorizing partner of your insurance company to determine if authorization is indicated. Even if your insurance plan authorizes the exam, that doesn’t mean they will fully pay for the exam or biopsy. This depends on your deductible and your particular plan.
The Women’s Imaging Center has specialist staff dedicated to requesting this authorization from your insurance. If the insurance declines to authorize an exam, you have the right to contest this with an advocate at your insurance company. Remember that you can also pay out of pocket for any of your imaging exams here at The Women’s Imaging Center. All imaging studies at The Women’s Imaging Center are outpatient, independent of hospital charges or facility step-up fees, and therefore lower cost. We work hard to ensure that women have access to imaging services they need without cost being a barrier.