The RatCAP conscious small animal PET tomograph

The RatCAP is a small, head mounted PET tomograph being designed and built to image the brain of an awake rat It will allow PET imaging studies to be carried out on laboratory rats without the use of anesthesia, which severely suppresses brain functions and affects many of the neurological activities that one would like to study using PET. In addition, it will allow the study of animal behavior while simultaneously acquiring PET data. The tomograph consists of a 4 cm diameter ring containing 12 block detectors, each of which is comprised of a 4×8 array of 2.2×2.2×5 mm ³ LSO crystals read out with a matching APD array. The APDs are read out using a custom designed ASIC and VME readout system. Most of the detector components for the RatCAP have been received and the final detector is now under construction. This paper summarizes the status of the project and gives results on detector component testing and performance, development of the readout system, results on image reconstruction, and studies on animal behavior while wearing the ring.