Sound vs xrays
Mammograms use xrays to image the breast tissue.
Screening mmgs involve 2 views (mlo, cc) of each whole breast. Ultrasound uses sound waves to produce images of the breast tissue. The area visualized is dependent upon where the probe is placed on the breast and is influenced by how it is angled, how fast it is moved around and how much attention is being paid to the screen during the exam.