An improved anger detector approach for PET with high resolution and sensitivity

Small-animal PET has become a rapidly growing approach to problems in human health, from addiction to cancer to drug development. However, the best presently available PET technology (∼2 mm resolution) still has significant limitations in spatial resolution and sensitivity which are particularly problematic for applications attempting to take advantage of powerful transgenic mouse models. Most currently proposed approaches to improving resolution face a number of technical obstacles which force trade-offs in performance. A novel design which circumvents many of these compromises is a miniaturized and modernized "Anger" or "gamma" camera, with a principle similar to well-known detectors for SPECT, in which a continuous scintillator crystal is used and position is determined from light-sharing among groups of photodetectors. Critical improvements over the traditional Anger design include a more appropriate scintillator for PET (LSO), a thinner crystal for higher spatial resolution, and large-area avalanche photodiode (APD) technology as the photodetector which allows layering of the detector to improve sensitivity, among other benefits. The feasibility of the approach has been studied in terms of spatial and energy resolution, sensitivity, and cost, with promising results. A prototype is complete and preliminary measurements have been performed.