Assessment and Improvement of FMRI Normalization Based on Inversion-Recovery Prepared High-Resolution EPI

Pooja Gaur¹, Helen Egger¹, Nan-kuei Chen²

EPI based fMRI has several major limitations: distortion, low spatial-resolution, and low anatomic resolvability. Therefore, it is not easy to register fMRI data to structural images, and to normalize fMRI data. EPI distortion correction and nonlinear normalization methods have been developed to address these limitations. However, it is not easy to assess how these methods perform on fMRI data with distortions, limited resolution, and anatomic resolvability. Here we report an imaging protocol based on high-resolution inversion-recovery prepared segmented EPI (with identical distortion patterns as in single-shot EPI), enabling accurate assessment of the performance for distortion correction and nonlinear normalization algorithm.