How is a mammogram different from breast ultrasound?

Mammogram is an X-ray that yields images of the breast to look for microcalcifications while a breast ultrasound is an imaging study that converts high speed sound waves into pictures to assess the tissues within the breasts. A mammogram is conducted by compression of each breast in turn between two flat plates for a few seconds whilst the X-ray is taken. A breast ultrasound uses a small hand-held probe to move across the breasts, and takes about 10 to 30 minutes to complete the imaging.

A breast ultrasound is useful to:

• Evaluate the cause of breast abnormalities  
• Determine the nature of the breast lump (fluid or solid)
• Supplement other tests such as a mammogram or a breast MRI
• Aid the placement of needles for procedures such as a biopsy

Breast ultrasound cannot replace a mammogram in detecting microcalcifications useful in early breast cancer detection.