A breast ultrasound uses high-frequency sound waves to create images of the tissues inside the breast. Unlike a mammogram, a breast ultrasound can show hard to reach areas of the breast, including the area closest to the chest wall.
It is important to note that a breast ultrasound does not replace a mammogram, but it helpful to further evaluate abnormal results from a mammogram. When used in conjunction with mammography, it can increase breast cancer detection, especially in dense-breasted patients. Ultrasounds are used to see whether a breast lump is filled with fluid or if it is solid.