PATIENT MOVEMENT CORRECTION METHOD FOR CONE-BEAM COMPUTED TOMOGRAPHY

摘要

A patient movement correction method for cone-beam computed tomography based on an iterative refinement of an initial projection geometry estimate describing the spatial positions and orientation of an X-ray source and detector during the acquisition of X-ray projection images. The acquired set of X-ray projection images are used for computing intermediate CBCT reconstructions during the corrective iteration, and projection-image-specific corrective geometric transformations are established by maximizing the similarity of the measured and reprojected X-ray projection images. The corrective geometric transformations are determined in a projection-image-specific rotating coordinate system corresponding to the spatial positions and orientations of the X-ray source and X-ray detector during the acquisition of the X-ray projection images. The final CBCT reconstruction is computed using the corrected projection geometry estimate.