Breast imaging is an umbrella term for various medical tests that x-ray or scan breasts for abnormalities. These tests include mammograms, ultrasounds, magnetic resonance imaging (MRI), and ductograms. As the name suggests, breast imaging provides physicians with an internal picture of the breast, thereby allowing doctors to check for diseases such as cancer or to further examine suspicious lumps or other anomalies.
Breast imaging tests are an accompaniment to other exams to check for breast health. Self-exams, for instance, are non-invasive, non-medical tests that women are encouraged to perform regularly. If the self-exam detects lumps or other abnormalities, an imaging test may be ordered. The results from the imaging tests then help determine if further interventions, such as a biopsy, are necessary.
Physicians have used imaging since the 1920s to help detect diseases, but the modern tests for breast health were not used until the late 1960s with the first mammograms. Mammograms became mainstream a decade later as techniques improved. Since the 1970s, breast imaging technology has steadily evolved to include new types of tests and to provide clearer internal pictures of breast tissue. Medical studies credit advances in imaging with reducing the mortality rates of breast cancer and early detection of other diseases and conditions.
Mammograms are the best known form of breast imaging and remain the most common imaging test for breast health. Physicians began using mammography because the test exposes patients to much lower radiation levels than previous screening methods. In mammograms, breasts are compressed between two plates to thin the tissue so it is more easily x-rayed. Regular, preventative mammograms provide a baseline picture and are generally recommended as a normal screening tool once a woman reaches age 40. Women already diagnosed with breast diseases also are likely to receive regular mammograms to monitor the disease’s progress.
An ultrasound is a no-radiation form of breast imaging. High-frequency sound waves are aimed at the breast and the echos help create an internal picture. Ultrasounds may be helpful for women with dense breast issue, which makes a mammogram more difficult. The ultrasound test is usually used in conjunction with, rather than in place of, a mammogram.
MRIs of the breast also typically are used alongside, rather than instead of, mammography. Like the ultrasound, the MRI is a non-invasive, no-radiation imaging test. MRI images are produced by a combination of magnetic fields and radio frequency pulses. The images often are more detailed than those provided by a mammogram or ultrasound.
Ductograms are a fourth type of breast imaging test. Also known as an galactogram, the ductogram is a more specialized imaging test that focuses on the breast ducts. Physicians often order this test when a patient experiences unusual nipple discharge. A specialist injects the breast ducts with a contrasting agent and then performs a mammogram. The contrasting agent helps highlight any abnormalities in the ducts that a regular mammogram may miss.