System integration and performance study of MicroInsert-II PET system

Shouyi Wei, Washington University in St Louis

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PET provides an in vivo molecular and functional imaging capability that could be valuable for studying various disease using animal models through small-animal imaging. Previously, Micro Insert, a high-resolution small-animal PET system that can improve the image resolution of a commercial PET scanner was developed and validated. This work studies the system integration of MicroInsert-II, a second generation PET insert system, as both a standalone PET and a virtual-pinhole PET. The initial performance of the system was evaluated based on the detector energy resolution, system timing resolution and crystal efficiency, and line source imaging experiment. The results indicate a 14.5 ± 1.1% FWHM detector block energy resolution, 1.94 ± 0.38 ns detector timing resolution from the standalone mode, and ~2 ns cross-ring timing resolution and uniform cross-ring crystal efficiencies in the scanner-insert mode. The reconstructed line source image also indicates the good working status of the system. Our system exhibits the potential to provide a sub-millimeter resolution imaging capability both as a standalone PET system and a virtual-pinhole PET insert.