Breast Ultrasound

Breast ultrasound uses harmless high-frequency sound waves to create real-time images of the inside of the breast. It is often used alongside mammography rather than as a replacement, because it provides information that X-rays cannot. One of its most valuable roles is distinguishing a solid mass from a cyst, which is a harmless fluid-filled sac, since the two can feel and look similar but are managed very differently. Ultrasound is also useful for examining a specific lump, for evaluating areas that are difficult to assess on a mammogram in women with dense breast tissue, and for looking at the lymph nodes under the arm. Because it does not use radiation, it is frequently chosen for younger women and during pregnancy, and it is the most common method used to guide a needle precisely during a biopsy.

Breast ultrasound requires almost no preparation. There is no need to fast or to change medications beforehand. It is helpful to avoid applying lotion or powder to the breast on the day of the test, and wearing a two-piece outfit allows the upper clothing to be removed comfortably.

During the examination, the person lies on their back or slightly on their side, and a clear gel is applied to the breast to help the sound waves travel. The sonographer moves a small handheld device called a transducer over the breast, and images appear immediately on a screen. The test is painless and involves no radiation.

Breast ultrasound is considered safe and has no known harmful effects, since it uses sound waves rather than radiation. As with any imaging test, it can occasionally identify an area that requires further evaluation but ultimately proves harmless.

The findings are interpreted together with any mammogram and described using the standardized BI-RADS system. If an area appears suspicious, the next step is often an ultrasound-guided biopsy, in which the live images are used to direct a needle accurately to the area of concern. A clearly benign finding, such as a simple cyst, may need no further action beyond routine follow-up.

FREQUENTLY ASKED QUESTIONS

Does a breast ultrasound use radiation?

• No. Ultrasound uses harmless sound waves rather than radiation, which is one reason it is often used for younger women and during pregnancy.

Why do I need an ultrasound if I already had a mammogram?

• Ultrasound provides information a mammogram cannot, such as showing whether a lump is a solid mass or a fluid-filled cyst, and it is especially helpful in dense breast tissue. The two tests work together.