Influence of MRI artifacts on PET image reconstruction using MRI-based priors

MRI information can be used to improve PET images by using Maximum A Posteriori (MAP) reconstruction algorithms. The aim of this study is to assess the influence of MRI image quality using two different methods to incorporate MRI information: boundaries and Bowsher. MRI data are simulated with different artifacts: noise and intensity inhomogeneity (IIH). PET data are also simulated to assess the performance of reconstruction. MAP algorithms using MRI information improve PET image quality, but the MRI image quality clearly influences this improvement. Both methods are robust to noise and IIH, if the artifact levels are acceptable. The Bowsher method achieves better figures of merit, but it is more sensitive to noise and IIH.