Motion artefact reduction for exact cone-beam CT reconstruction algorithms

Abstract

Katsevich proposed a reconstruction algorithm for helical cone-beam CT which is theoretically exact. Even for large cone angles, it performs very well on static objects. But due to its limitation to the PI illumination window, it produces strong artefacts in the presence of motion. We propose a method to reduce these spreading motion artefacts significantly by adding a correction image. It uses a small portion of the voxel-dependent over-scan. Results of a simulation study with a 128 row scanner are shown.