SiPM applications in positron emission tomography: toward ultimate PET time-of-flight resolution

The development of PET/MRI multimodality, requiring magnetic field immunity of the photodetectors associated with an increased demand for time-of-flight capabilities with a strong impact on effective PET sensitivity and image quality, has pushed the medical imaging community to progressively replace photomultipliers, traditionally used in PET scanners, by solid-state photodetectors, avalanche diodes (APD) and silicon photomultipliers (SiPM). Recent years have seen spectacular progresses in the performances of SiPMs, in terms of photodetection efficiency (PDE), noise and cross talk reduction, timing performance, etc., not mentioning their availability in a large variety of dimensions and packages, as single photodetectors, but also linear arrays and matrices of different sizes. As a result of this, SiPMs are progressively becoming the photodetectors of choice for a new generation of time-of-flight PET scanners (TOF-PET)