LOW-DOSE PET IMAGE RECONSTRUCTION METHOD AND APPARATUS, AND DEVICE AND STORAGE MEDIUM

摘要

A low-dose PET image reconstruction method and apparatus, and a device and a storage medium, applicable to the technical field of PET imaging. The method comprises: according to collected projection data and a system matrix of a PET device, reconstructing a PET image to be reconstructed by means of a PET image reconstruction algorithm, and obtaining an initial reconstructed PET image; by means of a gradient operation and dictionary learning, respectively obtaining a horizontal gradient image sparse representation and a vertical gradient image sparse representation corresponding to the initial reconstructed PET image; restoring the horizontal gradient image sparse representation and the vertical gradient image sparse representation from a gradient domain to an image domain; obtaining a reconstructed PET image; determining whether the reconstructed PET image satisfies a target function; if yes, outputting the reconstructed PET image; otherwise, continuing to perform operations of image reconstruction, gradient operation, and dictionary learning on the PET image to be reconstructed, so that the reconstructed speed of a low-dose PET image is improved, the artifact degree of the reconstructed image is reduced, and the image quality of low-dose PET image reconstruction is further improved.