MODEL RELEASED. Woman patient undergoing a cranio caudal mammography examination of her right breast. Mammography is an X-ray technique which reveals fine details of internal breast tissues; its main application is in the early detection of breast cancer. To obtain an image, the breast is compressed into a relatively flat plane between two plastic sheets before exposing the tissues to X-rays. Small tumours detected at an early stage may sometimes be treated in a conservative manner without resort to a mastectomy, the surgical removal of the whole breast. Photographed at King's College Hospital, London.