ABSTRACT
To this day, mammography represents the main imaging modality for early detection of breast cancer. The chapter will provide a thorough treatment of the basic physical principles and the technological aspects of X-ray digital mammography. A general introduction to the biophysical properties of the tissues composing the breast and of their interactions with X-rays (see Section II, Chapter 28 of this book), together with an introduction to the concept of task-dependent detection performance, will be given in Section 19.2. Afterward, Section 19.3 will describe the geometrical specifications of a mammography device and the adaptation of the spectral composition of X-ray beams (and consequently the filtration choices) from the case of general radiology to the one peculiar to mammography. Section 19.4 is devoted instead to the calculation of the radiation dose imparted to the breast (see Section II, Chapter 29 of this book), to the application to the case at study of the most commonly used objective metrics for image quality evaluation (see Section II, Chapter 24 of this book), and to the description of the physical phantoms dedicated to their measurement (see Section IV, Chapters 55 and 57). A discussion dedicated to the various X-ray imagers used in digital mammography, driven from a treatment of the physical effects on which their detection properties are based, will be covered by Section 19.5 (see Section II, Chapter 23 of this book). Moreover, an overview of the up-to-date techniques for image display and processing (see also Section IV, Chapter 64 of this book), followed by a general description of computer-aided detection algorithms (see also Section IV, Chapter 60), will be given in Section 19.6. Finally, the last section of the chapter will be devoted to the introduction of advanced techniques stemming from digital mammography, like contrast-enhanced digital mammography, dual energy digital mammography, and breast density measurement, focusing on both the promising features and the unresolved issues of these techniques.356
