It has been demonstrated that a high-resolution positron emission tomograph can be constructed using six large-area position-sensitive sodium iodide NaI (T1) scintillation detectors. This research addresses a basic modification to the detection system that will result in significant performance improvements and a reduced system cost Specifically, it is planned to optically couple the system's detectors, enabling scintillation light to be shared by neighboring detectors. This eliminates the sharp boundaries between detectors, which will reduce the size of the effective gap between detectors, resulting in improved image quality. This should also permit substitution of a reduced number of larger round photomultipliers for the current rectangular array of the more expensive square photomultipliers. Phase I efforts will investigate techniques for optically coupling the detectors, techniques for position estimation near the boundaries of two optically coupled detectors, and the adaptation of the event-triggering system for use with optically coupled detectors. Phase II research will concentrate on incorporating the optically coupled detector system into a tomographAwardee's statement of the potential commercial applications ofthe research: This research will result in improved performance and lower cost of the current hexagonal positron emission tomograph produced by UGM Medical Systems, Inc. This will make the system even more ideally suited for clinical nuclear medicine applications such as the diagnosis of brain disorders or the assessment of myocardial viability than the currently available systemNational Cancer Institute (NCI)
