Why is a breast ultrasound done?
Ultrasound may be used to evaluate breast lumps.
Ultrasound is often used as an initial or early diagnostic tool to evaluate breast lumps.
Unlike computed tomography (CT) and X-rays, an ultrasound does not use ionizing radiation. For this reason, it is often recommended for individuals who are not good candidates for radiation-based imaging techniques.
People who should avoid radiation include:
- pregnant or breast-feeding women
- women under the age of 25
- women with breast implants
A doctor may also use ultrasound to help guide a biopsy needle so tissues can be collected from the lump and tested. This procedure is called an ultrasound-guided biopsy.
In many cases, a doctor will schedule a breast ultrasound after a lump is discovered during a routine physical exam or at home.
Other reasons why a breast ultrasound may be performed include:
- to assess unusual nipple discharge
- to evaluate cases of mastitis or inflammation of the mammary tissues
- to evaluate breast implants
- to assess symptoms, such as breast pain, redness, and swelling
- to assess skin changes, such as discoloration
- to help monitor existing benign breast lumps
- to help read the results of other imaging tests, such as magnetic resonance imaging (MRI) or mammogram
Preparing for the test
It is not a good idea to put on any lotions or powders before the test, as they can decrease the accuracy of ultrasound images.
Any form of metal can also interfere with the test, so jewelry and watches are best left at home.
The test is usually done by a sonographer. A radiologist may also be present or perform the test.
The sonographer or radiologist may be male. Those who wish to have a female person perform the test should make this request beforehand.
It is also usually possible to bring a chaperone, such as a nurse, relative, or friend, who can stay in the room during the test.
Most breast ultrasounds are done in the radiology department of a hospital, or in a private or specialty clinic.
Wearing a separate top and bottom makes it easier to half-undress and provides more privacy. For some people, choosing a button-up or zippered shirt can also make the undressing process more comfortable.
What to expect
Most breast ultrasounds last between 15 to 30 minutes. Ultrasound tests are usually painless unless the lump is tender.
Ultrasound may be recommended as radiation should be avoided by women who are under the age of 25.
The process begins with the sonographer physically examining the breast. They will then usually ask questions about the lump, such as when it was noticed, if other symptoms are present, and how it has progressed.
After the examination, the sonographer will apply a cool, clear gel to the breast. By limiting air bubbles, this gel increases the ability of sound waves to move through tissues.
In some cases, the sonographer will place a triangular pillow under the shoulder, causing the body to roll to one side. The arm may also be raised over the head. These positions can make it easier for the sound waves to travel and be received.
The sonographer may dim the lights in the room to make the computer screen and images easier to see.
Once the gel has been evenly spread, the sonographer will pass a wand-like device called a transducer over the breast. The transducer sends sound waves through the breast and records their activity.
When a sound wave hits a tissue or structure, it is bounced back. Information about how long it takes for the wave to bounce back, its amplitude or loudness, and the pitch or frequency, is sent from the transducer to a computer that translates it into an image called a sonogram.
The sonographer will look at all the tissues and structures of the breast and take still shot pictures at several different sites and angles.
They will usually take multiple pictures of the lump and surrounding area. Short moving videos may also be recorded.
After the breast, the armpit region will also be examined for swollen or hard lymph glands and nodes.
If a sonographer has any concerns about the image's accuracy, they may ask for a radiologist's perspective. Sometimes the radiologist may need to redo portions of the ultrasound to evaluate the area of concern.
After the test is complete, the person will be given a tissue to wipe off the gel and will be given privacy to get dressed. A follow-up appointment to discuss results will usually be set up before the person leaves.
Results may be sent to a family doctor, who can explain the results at their office.
Waiting for the results of a health test can be stressful. It is easy to imagine the worst-case scenario, but it is important to note that around 80 percent of breast lumps are noncancerous, or benign.
Cysts do not usually require any further medical intervention unless they are causing pain or are near breast ducts or blood vessels.
Depending on the individual doctor, practice, or hospital, the results may be ready the same day or a few days later.
In most cases, the results will be written up and sent to a family doctor who will then go over the results during an office visit.
Other factors that influence how quickly results are processed include:
- how concerning to health the symptoms seem
- whether the radiologist needs more information to interpret the results
- whether the results need to be compared to previous ultrasounds or other imaging test results, such as a CT scan or X-ray
- whether the symptoms are considered the result of an underlying or pre-existing medical condition
- how the results are delivered, for example, by email, fax, phone, or surface mail
Fluid and solid tissue appear differently on the sonogram. If the lump is confirmed as a fluid-filled cyst, the results may be discussed over the phone.
If the lump is not diagnosed as a fluid-filled cyst, then an ultrasound alone is not enough to confirm or rule out other health complications. An MRI and biopsy are often used to evaluate further abnormal ultrasound results.
When interpreting inconclusive or abnormal results, it is helpful to keep in mind that cancer is not the only health condition known to cause breast lumps.
Common causes of noncancerous breast lumps include:
- fibrocystic breasts
- intraductal papilloma
- adenofibroma or fibroadenoma
- fatty lumps made of bruised, dead, or injured mammary fat cells
- hyperactive breast glands
- hormone conditions, changes or therapies
- mastitis or breast infection
- certain medications