Author:

Keywords:

computed tomography (ct) reconstruction, iterative reconstruction, metal artifact, projection completion, statistical image-reconstruction, ray computed-tomography, attenuation correction, dental implants, hip prostheses, reduction, pet/ct, algorithm, segmentation, simulation, Science & Technology, Technology, Life Sciences & Biomedicine, Computer Science, Interdisciplinary Applications, Engineering, Biomedical, Engineering, Electrical & Electronic, Imaging Science & Photographic Technology, Radiology, Nuclear Medicine & Medical Imaging, Computer Science, Engineering, Computed tomography (CT) reconstruction, STATISTICAL IMAGE-RECONSTRUCTION, RAY COMPUTED-TOMOGRAPHY, ATTENUATION CORRECTION, DENTAL IMPLANTS, REDUCTION, PET/CT, ALGORITHM, SEGMENTATION, EMISSION, SCATTER, Algorithms, Artifacts, Computer Simulation, Dental Restoration, Permanent, Hip Prosthesis, Humans, Image Processing, Computer-Assisted, Markov Chains, Metals, Phantoms, Imaging, Prostheses and Implants, Reproducibility of Results, Tomography, X-Ray Computed, 08 Information and Computing Sciences, 09 Engineering, Nuclear Medicine & Medical Imaging, 40 Engineering, 46 Information and computing sciences

Abstract:

Metal implants such as hip prostheses and dental fillings produce streak and star artifacts in the reconstructed computed tomography (CT) images. Due to these artifacts, the CT image may not be diagnostically usable. A new reconstruction procedure is proposed that reduces the streak artifacts and that might improve the diagnostic value of the CT images. The procedure starts with a maximum a posteriori (MAP) reconstruction using an iterative reconstruction algorithm and a multimodal prior. This produces an artifact-free constrained image. This constrained image is the basis for an image-based projection completion procedure. The algorithm was validated on simulations, phantom and patient data, and compared with other metal artifact reduction algorithms.