Hardware Attenuation Correction in PET/MR Hybrid Imaging: Evaluation of -Maps for Local RF Coils

Daniel H. Paulus¹, Harald Braun¹, Harald H. Quick¹

In hybrid PET/MR imaging local receiving RF coils, placed in the FOV, attenuate and scatter PET annihilation photons thus affecting PET quantification. Flexible RF surface coils are yet omitted in PET attenuation correction (AC), because they can vary in position and geometry. Several CT-based attenuation maps (-map) of the RF coil were used for PET AC to evaluate the effect of different parameters. Furthermore small shifts and rotations of the -map simulating misregistration or motion of the patient were analyzed. Depending on the PET reconstruction algorithm the shifts can cause artifacts or just a bias of the activity concentration.