Low performing pixel correction in computed tomography with unrolled network and synthetic data training
This work addresses the challenge of ring and streak artifacts in computed tomography (CT) caused by low-performance pixels (LPP) in detectors, which severely compromise clinical diagnosis. The authors propose a dual-domain joint correction method based on an unrolled network that, for the first time, integrates the CT geometric forward model into a deep learning framework to collaboratively model LPP-induced artifacts in both the sinogram and image domains. Training data are synthesized from natural images, eliminating the need for real clinical defect measurements and enabling end-to-end training as well as cross-scanner deployment. Under simulated detector defect rates of 1–2%, the proposed method significantly outperforms existing techniques, effectively suppressing artifacts while demonstrating strong practicality and generalization capability.