Full field digital mammography: which equipment?

A wide variety of digital mammography systems are now commercially available. These include digital radiography (DR) systems such as the CSi/amorphous silicon detector (for example, GE Senographe 2000D, DS and Essential models), amorphous selenium (for example, LoRad Selenia, Siemens Novation and Inspiration models, IMS Giotto, Planmed Nuance) and a scanning system with silicon detectors (for example, Sectra Micro Dose Mammography). A variety of computerised radiography (CR) systems for mammography are also available (for example, Fuji Profect, Kodak DirectView, Konica Regius 190, Agfa CR 85-X). Recently the CR manufacturers have introduced new designs of phosphor plates. Such a wide variety of systems raises the question of how the performances of these systems compare with each other and with film-screen technology. Another factor to be considered is the radiation dose required by each system to reach an acceptable level of image quality.

To help answer these questions, the National Health Service Breast Screening Programme and European Guidelines specify minimum and achievable standards for dose and image quality. The minimum standard is designed to ensure that new digital systems are at least as good as the previous film-screen systems. This lecture compares the measurements on a wide range of digital systems against the standards in the European Guidelines. The overall conclusion is that the DR systems can generally meet the achievable image quality standards for a dose lower than that used for film-screen systems. While the new designs of CR plate have brought about measurable improvements, most CR systems still require doses higher than film-screen systems to meet the minimum standards for image quality.