The present disclosure relates to a PET detector module suitable for using in a PET/MR hybrid system. The PET detector module comprises a scintillator, a set of frontend electronics and a positioning means configured to securing relative position between the scintillator and the frontend electronics. The PET detector module may further comprise a temperature control system, such as an air-cooling system or a heat exchange plate. The present disclosure also relates to a heat exchange plate, which comprises a fluidic passage for containing a flow of a heat exchange media. The heat exchange plate is suitable for use in the magnetic field environment of a MRI system.
