Patent ID: 7630473

Claim:
A method for correcting a truncation artifact in a tomographic process of an object under a medical examination, comprising: emitting a divergent radiation to the object by a radiation source, wherein the divergent radiation is a fan of radiation beams coming from a focus of the radiation source; transilluminating the object by the divergent radiation in a projection direction; measuring the radiation penetrating the object by a detector; recording a projection image of the object by the detector detecting the radiation at the projection direction; disposing an equivalent body in a region of the object; projecting the equivalent body onto an extended surface of the detector according to a geometry of the fan of the radiation beams without resorting the fan of the radiation beams to a parallel of the radiation beams; determining the equivalent body that attenuates the radiation based on the object in an edge region of the projection image; determining a radiation attenuation caused by the equivalent body for an extrapolated pixel outside the projection image; determining the extrapolated pixel outside the projection image based on the radiation attenuation; extending the projection image by an extrapolation based on the extrapolated pixel; and using the projection image in the medical examination.