APPARATUS AND METHOD FOR FAST ITERATIVE RECONSTRUCTION IN COMPUTED TOMOGRAPHY

摘要

A computed tomography (CT) apparatus and a method for reducing computational complexity in reconstructing a region of interest within an image is provided. The CT apparatus includes a processing circuit that obtains scan data from a scan of an object and computes a system matrix for one view angle of an X-ray source. The system matrix maps an image of the object represented on a circular, symmetric grid to the scan data of the object. Further, the processing circuit reconstructs the image iteratively until a predetermined stopping criterion is satisfied using the scan data and the computed system matrix and generates a sinogram of the reconstructed image based on a forward-projection model. The processing circuit analytically reconstructs a region of interest using the generated sinogram and a predetermined reconstruction kernel.