The Performance of Silicon Photomultipliers in Cherenkov TOF PET

Silicon photomultipliers (SiPMs) were considered as photodetectors in Cherenkov time-of-flight positron emission tomography (TOF PET) due to their relatively high photon detection efficiency (PDE) which resulted in a higher gamma detection efficiency of the Cherenkov PET detector. SiPMs produced by KETEK, AdvanSiD, SensL and Hamamatsu were tested in this application. The coincidence time resolution, gamma detection efficiency and single side event rates were measured in a simple experimental setup, consisting of two detectors placed in a coincidence configuration. The apparatus was cooled to -25° C in order to reduce the SiPM dark count rates. A single side gamma detection efficiency of up to 26% was measured, which is a marked improvement over previous Cherenkov TOF PET measurements. The best measured coincidence time resolution of 297 ps FWHM was limited by the time response of the SiPMs used for this experiments.