The invention relates to a medical device operating with X-rays, comprising: an X-ray source, from which an X-ray beam that has an intensity maximum along a central ray can be emitted, a rotation unit, with which the X-ray source can be rotated about an isocenter, wherein the central axis of the X-ray beam is oriented eccentrically to the isocenter such that, in particular upon rotation about the isocenter, the central rays emitted from different spatial directions are tangential to an imaginary circle around the isocenter. Furthermore, the invention relates to a method for operating a medical device, comprising the following steps: providing an X-ray source, from which an X-ray beam that has an intensity maximum along a central ray is emitted, rotating the X-ray source about an isocenter.
