What Is a Breast Ultrasound?

A breast ultrasound is a medical imaging study of the breast that a doctor might request to learn more about a lump or unusual structure, or if a mammogram is not suitable for a patient. During the ultrasound, the doctor or a technician will move a probe across the breast to introduce high-frequency sound waves, and the probe will record the waves as they return, generating an image of the inside of the breast. This test is not invasive and carries no known risks to the patient. It can take about a hour to complete, including all of the paperwork, a preparatory interview and the test itself.

One reason a doctor might ask for a breast ultrasound is if a patient has extremely dense breasts or large implants that make it difficult to visualize the breast tissue on a mammogram. Although mammography is the standard for early detection of breast abnormalities, it can be difficult to evaluate some women, so ultrasound might be preferable. A doctor also can order an ultrasound if mammography or a physical exam reveals a lump or abnormality in the breast.

During a breast ultrasound, the doctor can identify any structures in the breast and determine whether they are simply fluid-filled cysts, cancerous growths or something else. The doctor might request a follow-up breast ultrasound to monitor the size and development of any breast abnormalities. It also is possible to use Doppler ultrasound to evaluate the blood supply to the breast or to a specific lesion or growth inside the breast.

In the event that a doctor thinks a biopsy would be advisable, one option is to perform an ultrasound-guided procedure. During this procedure, the doctor uses the real-time images of ultrasound to carefully guide a needle into place to collect a sample of fluid or tissue with an aspiration biopsy. This is less invasive than some other biopsy options and can be a good start for evaluating a medical issue.

When a doctor requests a breast ultrasound, the patient might want to ask why the procedure is recommended and what might happen next. This information can help a patient prepare and might make the experience less frightening. During the test itself, the patient will need to take off her shirt and bra before lying on a table and moving her arm up and behind her head to expose the breast tissue. The technician will apply a small layer of conductive gel to make the images clearer and might warm the gel briefly for comfort. During the test, the patient might experience some pressure from the probe, but it should not be painful.