For breast ultrasound, a device called a transducer is passed over the breasts, directing high-frequency sound waves (ultrasound) through the underlying tissue. The sound waves are reflected back to the transducer, where they are electronically converted into images of the internal structures that are displayed on a viewing monitor. These images can then be saved on film or video and reviewed for abnormalities.

Ultrasound may be performed in addition to or instead of mammography to examine breast tissue in some women. For example, it is more accurate than mammography for detecting abnormalities in the denser breast tissue of younger women.

Purpose of the Breast Ultrasound

  • To determine whether a lump or abnormality found on a mammogram is a cyst (fluid-filled) or a solid tumor (which may be benign or malignant)
  • To identify and evaluate breast masses in individuals for whom mammography is less effective, including women under the age of 25 (whose breast tissue is too dense for mammography); those with silicone breast implants; obese women or those with larger breasts; and women with masses that are located in the difficult-to-assess area close to the chest wall
  • To monitor a previously detected breast cyst to see if it will enlarge and require treatment or if it will disappear
  • Breast ultrasound is used instead of mammography in pregnant women, since even small amounts of radiation may be harmful to the fetus

Who Performs It

  • An ultrasound technician, radiologist or sonographer

Before the Breast Ultrasound

  • Do not apply any lotions or powders to your breasts or wear deodorant under your arms prior to the exam.
  • Just before the test, you will be asked to disrobe from the waist up and put on a hospital gown.

What You Experience

  • You will lie on your back on an examining table and may be asked to raise your arm above your head.
  • A water-soluble gel is applied to your breasts to enhance sound wave transmission.
  • The ultrasound technician then moves the transducer back and forth over your breasts to obtain different views while observing the images displayed on a screen.
  • Once clear images are obtained, they are recorded on film, video, or paper for later analysis.
  • Alternatively, you may be asked to lie on your stomach on an examining table that contains a tank of heated, chlorinated water. One breast at a time is immersed in the water; the ultrasound transducer is located at the bottom of the tank.
  • Breast ultrasound generally takes about 30 minutes.
  • There is no discomfort associated with this procedure.

Risks and Complications

  • Ultrasound is noninvasive and involves no exposure to radiation. There are no associated risks or complications.
  • Sometimes, areas that seem concerning on an ultrasound are proven to be non-cancerous after additional testing. Know that a follow-up ultrasound and/or breast aspiration or biopsy may be needed because of this.

After the Breast Ultrasound

  • The examiner removes the conductive gel from your skin.
  • You may leave the testing facility immediately after the test and resume your normal activities.


  • A radiologist reviews the recorded images for evidence of any abnormalities such as a cyst or a tumor.
  • If the ultrasound images are normal, your physician will advise you about when to schedule your next breast ultrasound or mammography appointment, depending on your age.
  • If a fluid-filled cyst is identified, your doctor will recommend appropriate treatment, such as drainage with a needle. Most cysts are benign.
  • If a solid breast tumor is found by ultrasound, a mammogram or a breast biopsy is usually recommended for further evaluation.


The Johns Hopkins Consumer Guide to Medical Tests

Simeon Margolis, M.D., Ph.D., Medical Editor

Updated by Remedy Health Media

Publication Review By: the Editorial Staff at

Published: 11 Jan 2012

Last Modified: 17 Oct 2014