Over the past 15 years, the technical advancements in mammography have greatly improved both technique and results. Today, dedicated equipment, used only for breast x-rays, produces studies that are high in quality with negligible radiation risk. There are screening mammograms and diagnostic mammograms. Screening mammograms detect breast changes in women who have no sign of breast cancer and can detect a tumor that cannot be felt. Diagnostic mammogram detects unusual breast changes, such as discharge, thickening, or a lump.