Motion Correction in Cone-Beam CT by Tracking Internal and External Markers Using Cone-Beam Projection From a kV On-Board Imager: Four-Dimensional Cone-Beam CT and Tumor Tracking Implications

摘要

An apparatus comprising a processor configured to receive a sequence of Cone-Beam Computed Topology (CBCT) projections of a three dimensional (3D) object over a scanning period, wherein the 3D object is displaced during the scanning period, and wherein each of the CBCT projections is associated with a discrete point during the scanning period, locate a marker position in a plurality of the CBCT projections, wherein each marker position corresponds to the location of an internal marker at the corresponding discrete point during the scanning period, extract a 3D motion trajectory based on the plurality of marker positions and a plurality of time-tagged angular views, and correct the CBCT projections based on the 3D motion trajectory.