A mammogram is a specific test used exclusively to x-ray the breast for both screening and diagnostic purposes. When used in a screening capacity, each breast is positioned between two plates to flatten and spread the tissue, a necessary uncomfortable factor to enable good imaging. This typically will last only a few seconds with the whole process lasting about 20 minutes. The machine will take general x-rays of each breast to ensure detection of abnormalities missed during breast exams.

Diagnostic mammograms are much the same process save they take longer and have a different emphasis. If an abnormality is detected through breast exam, screening mammogram or naturally occurring symptoms, a diagnostic exam is needed to produce a higher resolution image of a specific region (or regions) to gain greater detail for better analysis. The machine takes a larger number of x-rays from various angles compared to regular screenings, resulting in a longer test . Your doctor will use these pictures to gain a better understanding to make a diagnosis, or to initiate more tests including an ultrasound, MRI, or biopsy.