Development of brain PETusing GAPD arrays

orthosilicate (LYSO) crystals coupled with a 4 � 4 array three-side tileable GAPD. The signals from each PET module were fed into preamplifiers using a 3 m long flat cable and then sent to a position decoder circuit (PDC), which output a digital address and an analog pulse of the interacted channel among 64 preamplifier signals tranmitted from four PET detector modules. The PDC outputs were fed into field programmable gate array (FPGA)-embedded data acquisition (DAQ) boards. The analog signal was then digitized, and arrival time and energy of the signal were calculated and stored. Results: The energy and coincidence timing resolutions measured for 511 keV gamma rays were 18.4 63.1% and 2.6 ns, respectively. The transaxial spatial resolution and sensitivity in the center of field of view (FOV) were 3.1 mm and 0.32% cps/Bq, respectively. The rods down to a diameter of 2.5 mm were resolved in a hot-rod phantom image, and activity distribution patterns between the white and gray matters in the Hoffman brain phantom were well imaged. Conclusions: Experimental results indicate that a PET system can be developed using GAPD arrays and the GAPD-based PET system can provide high-quality PET imaging. V C 2012 American Association of Physicists in Medicine. [DOI: 10.1118/1.3681012]