Like all x-rays, mammograms use doses of ionizing radiation to create images. Radiologists then analyze the image for any abnormal findings.
At this time, mammography along with physical breast examination is the modality of choice for screening for early breast cancer.In screening mammography, both head-to-foot (craniocaudal, CC) view and angled side-view (mediolateral oblique, MLO) images of the breast are taken. Diagnostic mammography may include these and other views, including geometrically magnified and spot-compressed views of the particular area of concern. Ultrasound, ductography, positron emission mammography (PEM), and magnetic resonance imaging are adjuncts to mammography. Ultrasound is typically used for further evaluation of masses found on mammography or palpable masses not seen on mammograms. Ductograms are still used in some institutions for evaluation of bloody nipple discharge when the mammogram is non-diagnostic. MRI can be useful for further evaluation of questionable findings as well as for screening pre-surgical evaluation in patients with known breast cancer to detect any additional lesions that might change the surgical approach, for instance from breast-conserving lumpectomy to mastectomy.
Breast self-examination (BSE) was once promoted as a means of finding cancer at a more curable stage, however, it has been shown to be ineffective, and is no longer routinely recommended by health authorities for general use.Awareness of breast health and familiarity with one's own body is typically promoted instead of self-exams.
Mammography has a false-negative rate of at least 10 percent. This is partly due to dense tissues obscuring the cancer and the fact that the appearance of cancer on mammograms has a large overlap with the appearance of normal tissues.