Testing of the spatial resolution and efficiency of scintillating fiber PET modules

Two experimental PET (positron emission tomography) camera modules were constructed using (1) two 5-cm*5-cm*2.5-cm detector stacks made of parallel 0.5- and 1.0-mm-diameter scintillating fibers and (2) two 5-cm*5-cm*5-cm detector stacks made of alternating x and y layers of 0.5- and 1.0-mm-diameter scintillating fibers. Each stack was viewed by Hamamatsu R2486 position-sensitive photomultipliers. The time resolution of the coincidence system was 10 ns. The spatial resolution and efficiency of the PET modules were tested using an approximately 1 mu Ci. 0. 5-mm-diameter Na-22 source. The best results were achieved with the 1.0-mm parallel fiber stacks: 2.0-mm spatial resolution (full width at half maximum) and 2.3% efficiency. The possibilities of improving the characteristics of this arrangement and particularly the alternating x and y layer stacks are discussed.<
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