Breast MRI

Breast MRI has rapidly established itself as an essential tool for the evaluation of breast disease. When used together with mammography and ultrasound, Breast MRI can provide valuable information for the diagnosis and staging of breast cancer. It is used primarily for determining the extent of disease in newly diagnosed cases, monitoring the response to neo-adjuvant chemotherapy in breast cancer patients and screening patients at high risk for breast cancer.

Frequently Asked Questions

What is Breast MRI?

Breast MRI uses Magnetic Resonance Imaging to look at the breast. It is a non-invasive procedure that provides information that may not be available with traditional mammography. MRI does not use x-rays to make images; instead MRI creates images by detecting the response of magnetic fields to radio frequency signals.

Is it a substitute for Mammography?

No! MRI does not replace mammography. Traditional mammography remains the standard for breast cancer detection and there are breast cancers that are found on the regular mammography, that are not found on MRI. In selected patients, however, MRI may add important information that is not available by standard testing.

What is the difference between Breast MRI & Mammograms?

Mammograms use x-rays to generate images of a breast. MRI on the other hand uses no x-rays and compression of the breast is not needed. MRI does require injection of a contrast agent, which helps highlight abnormalities.

Who should have a Breast MRI?

The following patients are candidates for Breast MRI:

High Risk - The American Cancer Society guidelines recommend an annual MRI, as well as a mammogram, for women who are at high risk of developing breast cancer.

Diagnosed with Breast Cancer - The New England Journal of Medicine released information on a national study suggesting that women, who have had cancer diagnosed in one breast, also get a Breast MRI to further evaluate both breasts.

Newly Diagnosed with Breast Cancer - In many patients, MRI can help determine the extent of breast cancer and assist in choosing the best treatment options.

Cancer Treatment Therapy - It may also be useful to monitor patients for response to treatment and for evaluation of recurrent breast cancer.

Implants - MRI is also recommended for women with implants to evaluate both the implant and the breast.

What if I am claustrophobic?

Patients with minor claustrophobia (fear of enclosed spaces) or some anxiety, may want to ask their physician for a mild sedative to take at the time of the exam. There is little discomfort involved in the exam and most patients do not require sedation.

What are the limitations and risks of Breast MRI?

MRI may not detect some forms of invasive cancer or pre-invasive (in situ) cancers that may be seen on mammography or on pathology slides from a biopsy. This is one of the reasons why mammograms remain very important for diagnosis and follow-up.

The magnet attracts certain metals and you will be screened for the presence of metal before the exam. The magnet does affect dental fillings, surgical clips and staples.

What to expect during the procedure?

The Breast MRI scan takes about 25-30 minutes. Prior to the scan, the patient is asked to complete a history form that is reviewed with the technologist. Then, an IV is started and the patient is placed in the scanner facing down with both breasts suspended comfortably into a depression in the scanning table. During the scan, images are obtained for review by the radiologist.

Do hormones and menstrual cycle affect the Breast MRI exam?

Hormones create changes on MRI that may significantly alter the accuracy of the exam. For pre- menopausal women, it is best to perform MRI between days 7 and 10 from the first day of the start of the last menstrual cycle. For post-menopausal women, one must take into account hormone replacement therapy.

What happens after the scan?

The patient may leave as soon as the exam is complete. Since the computer generates thousands of images, the results will not be available immediately. A radiologist will interpret the scan and send the report to the patient's doctor. The referring doctor will contact the patient with the results.

For more information on this topic, please visit or Middle Tennessee's first dedicated bilateral Breast MRI facility at

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