Current status and requirements for position-sensitive detectors in medicine

This review considers the current status of detector developments for medical imaging using ionising radiation. This field is divided into two major areas; the use of X-rays for transmission imaging and the use of radioactive tracers in emission imaging (nuclear medicine). Until recently, most detector developments were for applications in nuclear medicine. However, in the past 5 years new developments in large area, X-ray-sensitive detectors have meant that both application domains are equally served. ay imaging, work in CT and mammography are chosen as examples of sensor developments. Photodiode arrays in multi-slice spiral CT acquisitions are described and for mammography the use of amorphous silicon flat panel arrays is considered. The latter is an excellent example where new detector developments have required a re-think of traditional imaging methods. ma-ray imaging the recent developments in small area, task-specific cameras are described. Their limitations and current proposals to overcome those limitations are considered. PET has also received attention but recent clinical emphasis has been on the development of dual-headed gamma cameras which provides both SPECT and PET capability. Finally, some future requirements are considered.