The invention is a tomographic apparatus, in particular for examining a brain or a limb of a human and/or a primate animal, the apparatus (10) comprising an examination space (16) adapted for receiving a subject of a tomographic examination, and a PET ring (12) and a second imaging arrangement, being arranged around the examination space (16) in a substantially coaxial manner. The tomographic apparatus according to the invention comprises a PET ring (12) being displaceable between a PET operational state and a PET non-operational state, and comprises a second imaging arrangement adapted for being brought from a second imaging non-operational state to a second imaging operational state in the PET non-operational state of the PET ring (12).
