A radiation detector comprises: a substrate (54)； a two-dimensional array of solid state detector elements (50) disposed on or in the substrate and defining a detector array area (52)； electrodes (Ec, Ea) disposed on or in the substrate； and electrically conductive connecting lines (60, 64) disposed on or in the substrate and operatively electrically connecting the solid state detector elements and the electrodes, the electrically conductive connecting lines arranged to define a maximum area in conjunction with any one conducting solid state detector element that is less than or about one tenth of the detector array area. An imaging system comprises an MR scanner (10) and a PET or SPECT imaging system arranged to have some interaction with a magnetic field generated by the MR scanner, the PET or SPECT imaging system including scintillator elements (40) and the aforesaid radiation detectors arranged to detect scintillations generated in the scintillator elements.
