What type of pathology is rarely identified by breast ultrasounds?

Microcalcifications are small deposits of calcium that can occur in the breast tissue and are often associated with certain types of breast lesions, including breast cancer. However, they are primarily identified through mammography rather than breast ultrasound. Ultrasound is more effective at characterizing solid masses and cysts rather than detecting microcalcifications, which may be too small or not sufficiently conspicuous to be visualized on ultrasound images.

On the other hand, breast ultrasound can effectively identify cysts, fibrocystic changes, and breast cancer. Cysts appear as fluid-filled sacs, fibrocystic changes encompass a variety of tissue alterations, and breast cancer typically presents as a solid mass, all of which can be visualized with ultrasound imaging. Therefore, microcalcifications remain the type of pathology that ultrasound is least capable of identifying, making it the correct answer.