This invention relates to magnetic resonance imaging (MRI) and spectroscopy (MRS) to single photon emission computed tomography (SPECT) imaging. In particular, the invention relates to the combination of MRI with SPECT systems for the purpose of hybrid imaging and to the use of materials with high dielectric constant or permittivity and with low electrical conductivity for RF field generation and for collimation of ionizing radiation. The invention relates to hybrid imaging and spectroscopy, in particular to industrial, preclinical and clinical applications as well as applications in material sciences.The invention describes an embodiment where a material is used in proximity of an RF coil. The material has high density and specific electromagnetic parameters (in particular the dielectric constant). The materials function is to collimate and attenuate ionizing radiation and to improve RF field profile of the RF coil.
