What is the difference between screening mammogram and diagnostic mammogram? Why does the diagnostic one have to be done with breast ultrasound?
Purpose. The purpose of a screening mammogram is to identify breast cancer in women who have no signs of disease, while the purpose of a diagnostic mammogram is to obtain more detail on a known abnormality identified on prior physical exam or imaging study. A diagnostic mammogram need not always be done with an ultrasound.
A screening. mammogram is a study of both breasts that is performed on asymptomatic women to try and detect signs of breast cancer. A diagnostic mammogram consists of special views, and is usually targeted to a specific area of the breast, to further evaluate a potential abnormality seen on screening mammo or felt on clinical exam. The diagnostic doesn't have to have an US, but US usually very helpful.
See. Radiologyinfo.Org and womenshealth.Gov for detailed info.