A tool for reducing cone-beam artifacts in computed tomography data

Abstract Cone-beam computed tomography (CT) with circular scanning trajectory is known to suffer from so called cone-beam artifacts. Cone-beam artifacts are errors in the reconstructed volume due to incomplete radon data. These artifacts increase with increasing distance of the reconstructed plane from the midplane, i.e. the plane containing the X-ray source. Theoretically, the midplane represents the ideal data set for tomographic reconstruction as the entire set of line integrals, i.e. the X-ray attenuation trajectories, are parallel to the plane they are used to reconstruct. The angle between the reconstructed plane and the line integrals used to reconstruct it increases with increasing distance from the midplane. Cone-beam artifacts generally result in a degradation of tomographically reconstructed edges, subsequently affecting dimensional measurements. Appearance of cone-beam artifacts depends on the position and orientation of the object under investigation in the measurement volume.