Detectors for digital mammography

Interest in digital radiography was stimulated by the enthusiastic acceptance of computed tomography in the early 1970s. It quickly became apparent to the medical community that images with improved information content, whose display characteristics could be manipulated by the viewer, provided many advantages. Subsequently, digital systems for subtraction angiography and later for conventional projection radiography and fluoroscopy were developed. The timing of the introduction of these systems was highly dependent on the readiness of certain key component technologies to meet the requirements of each of these applications. These components are the x-ray detectors, analog to digital converters, computers, data storage systems and high-resolution electronic displays and printers used in image acquisition, storage and display. Mammography represents one of the most demanding radiographic applications, simultaneously requiring excellent contrast sensitivity, high spatial resolution, and wide dynamic range at as low as radiation dose to the breast as is reasonably achievable while meeting the other requirements. For this reason, it is one of the last radiographic procedures to "go digital". Here, some of the considerations related to the detector technology for digital mammography will be discussed and systems currently available will be described.