A method and a device for imaging a volume section by way of PET data are described. With the proposed solution the PET data of the volume section are acquired by way of a positron emission detector, and the MR data of the volume section are acquired by way of a magnetic resonance system. In at least one embodiment, with the aid of the MR data, PET voxels within the volume section are determined from which radiation occurring due to an annihilation is emitted. The image data are reconstructed from the PET data in that it is taken into account that the PET data are generated only by radiation from the PET voxels.