Conference Paper

Can large-area avalanche photodiodes be used for a clinical PETIMRI block detector

Department of Radiology and Molecular Imaging Program, Stanford, University, CA, USA
DOI: 10.1109/NSSMIC.2008.4774466 Conference: Nuclear Science Symposium Conference Record, 2008. NSS '08. IEEE
Source: IEEE Xplore


We are investigating a high resolution, Angerlogic based PET block detector using large-area avalanche photodiodes (LAAPD). Such block detectors will be used in a simultaneous PET/MRI clinical scanner. Using a Monte-Carlo simulation tool, we systemically optimized the detector design taking into account the following factors: the dimensions of the scintillation crystal and the optical diffuser, the surface finish of crystals, the layout of APD arrays, and the signal-to-noise (SNR) of the system. Based on the simulation results, a block detector prototype was built with an 8×8 LYSO crystal array (crystal pitch size: 2.75 × 3.00 × 20 mm3) coupled to four APDs. The performance of the block detector with regard to the crystal resolving ability and the energy resolution is reported.

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