What it is (overview)

A Breast Ultrasound Scan (Bilateral) is a diagnostic imaging test that uses high-frequency sound waves (ultrasound) to create real-time pictures of the tissues inside both breasts. Unlike an X-ray or mammogram, ultrasound does not use radiation. A handheld device called a transducer is moved over the skin with gel to capture detailed images of breast tissue, ducts, and areas under the nipple and areola.

This imaging test does not “measure” a blood value; instead, it evaluates the structure and appearance of breast tissue. It is especially useful for: distinguishing a fluid-filled cyst from a solid mass, assessing a breast lump or area of pain, and examining findings seen on a clinical breast exam or mammogram. It can also help the radiologist look at breast tissue in people with dense breasts and can be used to guide procedures such as a needle biopsy or cyst aspiration.

What results can mean (in plain language): Your report typically describes whether an area looks like a simple cyst (usually benign and fluid-filled), a solid mass (which may be benign or suspicious depending on features), or a complex cyst/lesion that may need closer follow-up. The radiologist may provide a BI-RADS category (Breast Imaging Reporting and Data System), which helps communicate the level of concern and next steps. Results may recommend reassurance, short-interval follow-up imaging, or additional testing such as a diagnostic mammogram, MRI, or biopsy.

When & why it's usually done

A bilateral breast ultrasound is commonly ordered as part of a medical examination for breast health when there are symptoms, a physical finding, or an abnormality on another imaging test. It may be done on both breasts to compare tissue side-by-side and to check for additional areas that may not be felt on exam.

Doctors often recommend this breast screening and imaging test when you have:

• A new or changing breast lump or thickening
• Breast pain that is persistent or localized to one area
• Nipple discharge (especially spontaneous, bloody, or from one duct)
• Skin changes such as dimpling, redness, warmth, or swelling
• A change in nipple position (new inversion) or a new palpable area under the nipple
• An abnormal mammogram or unclear mammogram finding that needs further evaluation
• Dense breast tissue, where ultrasound may help detect lesions that can be harder to see on mammography
• Concern for cysts (for example, a tender, round lump that may fluctuate with the menstrual cycle)
• Enlarged lymph nodes in the armpit (axilla) or above the collarbone that may be related to breast conditions
• Monitoring a previously known benign finding (follow-up imaging)
• Guidance for procedures such as biopsy, cyst aspiration, or localization of a suspicious area

It may also be used in certain situations such as pregnancy or breastfeeding, where ultrasound is often the first-line imaging test for breast symptoms because it is safe and effective. Although breast ultrasound can help evaluate possible breast cancer, it is usually one part of an overall diagnostic plan and is often combined with mammography and/or other tests depending on age, symptoms, and risk factors.

Common diseases related to it

• Breast cysts (simple or complicated)
• Fibroadenoma (common benign solid breast lump)
• Fibrocystic breast changes
• Mastitis and breast abscess (infection/inflammation, including during breastfeeding)
• Breast cancer (including evaluation of suspicious masses)
• Intraductal papilloma (can be associated with nipple discharge)
• Duct ectasia (widened milk ducts, sometimes with discharge/inflammation)
• Breast hematoma or fat necrosis (often after injury or surgery)
• Benign lymph node enlargement or lymph node changes related to breast disease

Health goals where it may help

• Supporting breast health through timely evaluation of new symptoms or changes
• Improving early detection strategies for breast cancer alongside mammography when appropriate
• Clarifying the cause of a breast lump (solid vs. fluid-filled) to reduce uncertainty and guide next steps
• Monitoring known benign findings (e.g., cysts or fibroadenomas) with follow-up imaging test plans
• Guiding minimally invasive procedures (biopsy or cyst aspiration) to reach a diagnosis efficiently
• Enhancing women's health screening and personalized risk-based breast imaging decisions (especially with dense breasts)