Extending QuickSilver™ electronics for PET insert integration

The unique, circular topology of the QuickSilver electronics of the Siemens Inveon PET scanner distributes the coincidence event matching, as opposed to the traditional star structure with a centralized coincidence processor. This architecture provides a means to extend or integrate QuickSilver based systems without hardware modification. This paper reports on integrating a small, high-resolution PET insert, developed at Washington University (WU) in St. Louis, into a Siemens Inveon PET. The detectors in WU PET insert are equipped with LSO arrays coupled to Multi-Pixel Photon Counters (MPPC). Scintillation events detected by PET insert detectors are processed by a set of independent QuickSilver electronics. By placing this insert within the Inveon PET, one can achieve sub-millimeter resolution. By rerouting RocketIO (RIO, Xilinx standard) cables and modifying Field Programmable Gate Array (FPGA) firmware, the two PET systems can be integrated in such a manner as to create coincident pairs within the insert ring, within the original Inveon ring, and between the two rings.