Design and Development of the Human Dynamic NeuroChemical Connectome Scanner

The Human Dynamic NeuroChemical Connectome will consist of a High Spatio-Temporal Resolution brain-dedicated PET (HSTR-BrainPET) scanner integrated with a 7T MRI system. The primary goal is to build a PET camera with an order of magnitude higher sensitivity than existing MR-compatible PET devices to allow investigators to merge seamlessly the dynamic functional capabilities of both PET and functional MRI on a comparable time scale. The HSTR-BrainPET will maximize geometric efficiency (~70% solid-angle coverage) by arranging 872 detector modules around a sphere with 32 cm inner diameter. Each module will consist of a 10×10 array of 1.6×1.6×26 mm LSO crystals coupled to a 4×4 multi-photon pixel-counter with 4×4 mm
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pixels. A 380µm light guide applied to the entry face will allow depth-dependent light sharing. The readout electronics consist of customized ASIC signal processing boards (218) and MR-side HUB boards (28) positioned in the MR scanner and PC-side HUB boards (28) located in the equipment room and connected through optical fibers. Here, we describe the results of Monte Carlo simulations that showed the sensitivity will be ~25% (before accounting for the TOF sensitivity amplifier effect) and the count rate performance will be excellent. We also provide an update on the design and development of all the components of the HSTR-BrainPET, including the detector modules, readout electronics, multi-functional gantry that will house the LSO crystal arrays and electronics, distribute the cooling channels and provide electromagnetic shielding.