In this work, a unified framework was developed to jointly address scatter artifacts, detector nonuniformity-induced concentric artifacts, and beam hardening artifacts in C-arm photon counting detector (PCD) cone beam CT. By leveraging the energy-resolving capability of PCDs, a better estimation of the scattered photon signal was obtained via a photoelectric-Compton scattering decomposition. Next, detector nonuniformity and beam hardening artifacts were jointly corrected via a second-round projection domain pixel-wise material decomposition. Both phantom and in vivo animal results demonstrated that the proposed correction method generated high-quality and quantitative PCD cone beam CT images for image-guided interventions.
|