Breast Ultrasound

Ultrasound produces images of the internal structures of the breast by using high frequency sound waves. Breast Ultrasound is noninvasive, painless, and uses no radiation. Ultrasound may safely be used during pregnancy and on those with a contrast dye allergy. Based on the findings, the radiologist can determine whether a suspicious mass is fluid- filled, such as a benign cyst, or solid, such as a noncancerous mass or cancerous tumor. However, a breast ultrasound cannot determine whether a lump is 100% cancerous and, if necessary, a tissue biopsy would be recommended for a positive or negative confirmation.

Breast ultra sound results being shown to patients

If you’re under the age of 30, an ultrasound may be recommended to evaluate a palpable finding before, or in addition to, a mammogram. Mammograms can be difficult to interpret in young women because their breasts tend to be extremely dense. However, with the use of tomosynthesis mammograms, radiologists are able to visualize findings in dense breasts more effectively than with 2D mammograms. Most breast lumps found in young women turn out to be benign, such as a cyst or a fibroadenoma. It is important that a palpable finding be evaluated by imaging to confirm.

In addition, a physician may use an ultrasound device to aid in determining where specifically to do a biopsy or cyst aspiration. Because an ultrasound provides real time imaging, it allows the physician to locate the suspicious finding accurately and safely preform the necessary testing.

Breast ultra sound machine being used on a patient

Scheduling a Mammogram or Ultrasound after a COVID vaccine

The Society of Breast Imaging recently reported that the COVID vaccine can cause temporary enlargement of the underarm (axillary) lymph nodes. This is a normal reaction to some vaccinations, however this can lead to unnecessary additional workup with ultrasound and or biopsies. It has been recommended to avoid breast imaging (mammograms/ultrasound MRI) immediately after a vaccine injection. In order to eliminate unnecessary workups, after receiving the vaccine, we will follow these guidelines when scheduling a mammogram or ultrasound:

Screening or Diagnostic Mammograms and Ultrasounds

In addition to the standard COVID screening questions we will also ask patients, “Have you had or will you be having a COVID vaccine?”

If the answer is “yes” we will schedule your breast screening appointment at least 1 day BEFORE the FIRST vaccine dose or at least 2 weeks AFTER the SECOND vaccine dose.

We hope this approach will avoid unnecessary tests for our patient who have normal reactive lymph nodes.

This only applies to patients who do not have breast symptoms and or concerns. For patient with a breast concern, we will schedule as normal, and our technologist will get your medical history.

How Breast Ultrasound Works

Breast ultrasound uses a handheld probe called a transducer that sends out ultrasonic sound waves at a frequency too high to be heard. When the transducer is placed on the breast at certain locations and angles, the sound waves move through the skin and other breast tissues. The sound waves bounce off the tissues, like an echo, and return to the transducer. The transducer picks up the reflected waves which are then converted into an electronic picture of the breasts.

Prior to the procedure, clear, water-based gel is applied to the skin to allow for smooth movement of the transducer over the skin and to eliminate air between the skin and the transducer.

During an ultrasound procedure, blood flow within the breast can be assessed. An ultrasound transducer capable of assessing blood flow contains a Doppler probe. The Doppler probe within the transducer evaluates the velocity and direction of blood flow in the vessel by making the sound waves audible. The degree of loudness of the audible sound waves indicates the rate of blood flow within a blood vessel. Absence or faintness of these sounds may indicate an obstruction of blood flow.

Breast Cancer Screening Methods and Myths Webinar

Watch our breast cancer doctors at the Margie Petersen Breast Center at Providence Saint John’s, discuss the different types of breast cancer screening methods including, breast exams, mammography, ultrasounds, MRI, and biopsy, as well as share the facts for all the common breast cancer myths you’ve heard.

Meet Our Breast Health Care Team

The Margie Petersen Breast Center at Providence Saint John’s Health Center brings you some of the finest breast health and cancer care in Southern California.

Meet Our Breast Health Experts

Margie Petersen Breast Team


The Breast Health Clinic can be reached at (310) 582-7209. If you have questions regarding a new symptom or want to make an appointment for evaluation please call and a staff member will assist with navigating you in the right direction.

Schedule an Appointment For more information