Mammography is a specific type of imaging that uses a low-dose X-ray system to examine breasts. A mammography exam, called a mammogram, is used to aid in the early detection and diagnosis of breast diseases in women.
An X-ray (radiograph) is a noninvasive medical test that helps doctors diagnose and treat medical conditions. Imaging with X-rays involves exposing a part of the body to a small dose of ionizing radiation to produce pictures of the inside of the body. X-rays are the oldest and most frequently used form of medical imaging.
Two recent advances in mammography include digital mammography and computer-aided detection.
Digital mammography, also called full-field digital mammography (FFDM), is a mammography system in which the X-ray film is replaced by solid-state detectors that convert X-rays into electrical signals. These detectors are similar to those found in digital cameras. The electrical signals are used to produce images of the breast that can be seen on a computer screen or printed on special film similar to conventional mammograms. From the patient's point of view, having a digital mammogram is essentially the same as having a conventional film screen mammogram.
Stanford's all-digital mammogram creates a digital image that can be manipulated in ways that improve resolution and contrast. The clearer image improves interpretation, making it easier to view dense breast tissue and small tumors, and often eliminates the need for additional follow-up imaging.
Computer-aided detection (CAD) systems use a digitized mammographic image that can be obtained from either a conventional film mammogram or a digitally acquired mammogram. The computer software then searches for abnormal areas of density, mass, or calcification that may indicate the presence of cancer. The CAD system highlights these areas on the images, alerting the radiologist to the need for further analysis.
Tomosysnthesis (3D mammography)
Uses low dose X-rays to take mammogram images of the breast, and shows only a few layers of the breast at a time. Preliminary studies show higher cancer detection and lower false positives than full-field digital mammography (FFDM).