How often are ultrasounds ordered the same time a mammogram is?

It depends: If you have a lump that can be felt, it's likely the radiologist will want an ultrasound as well as mammogram. Mammogram uses x-rays to see calcifications that might indicate a breast cancer, while ultrasound uses sound waves to see different characteristics of breast tissue such as blood flow, size and shape of a lump and whether it's solid or cystic. Ultrasound is also used to guide biopsy.

Ultrasound: With the recognition of breast density as a risk factor for breast cancer, and the limitations of mammo in the setting of dense breasts, it is becoming more and more common for adjunct screening breast ultrasounds to be requested in addition to screening mammograms.The traditional role of ultrasound, as a problem solving tool and biopsy facilitator, is changing. So this is an evolving situation.