Anatomy-Guided Inverse-Gradient Susceptibility Artifact Correction Method for High-Resolution FMRI

Functional Magnetic Resonance Imaging (fMRI) is a widely used and non-invasive technique for recording changes in brain activity. However, susceptibility artifacts are ubiquitous distortions in fMRI, especially strong in high-resolution images, causing the misrepresentation of brain function and structure in the affected regions. Here, we present a novel method for correcting these distortions in high-resolution fMRI images based on the hyper-elastic susceptibility artifact correction (HySCO) method. The novelty of the proposed method is the utilization of the easily-acquired T1-weighted ( $\mathrm{T}_{1w}$ ) anatomy image as a ground-truth measurement to regularize deformations, thereby obtaining meaningful corrections. The performance of the new method is compared to that of HySCO. Results from high-resolution (1mm) EPI data are presented demonstrating the robustness of the new method for image correction and its suitability for subsequent fMRI analysis.