Mammography
Mammography is an X-ray examination of the breasts. A dedicated X-ray machine is required for mammography. Compared with conventional X-ray techniques, mammograms are obtained with much lower energy X-rays of around 20,000 volts. The X-rays are generated using a special fixed anode X-ray tube which has a molybdenum target rather than a tungsten target. The softer radiation produced helps to enhance the contrast between different types of breast soft tissue and makes abnormalities such as tumours and cysts more readily visible. Fine calcification, a feature of breast tumours, is also rendered more visible. The tube has a small 'focal spot' which gives excellent spatial resolution i.e. fine detail. Special X-ray film cassettes are also required to help maximize detail and contrast while minimize radiation exposure. Every step in the production and interpretation of a mammogram requires a fastidious approach and quality control is of major importance as breast cancer is a major cause of death and morbidity. Mammography is the best available technique to detect breast cancers at an early, curable stage.
