Resting state functional MRI with Multi echo GRE EPI on a high performance 0.5 T Head-only Scanner

Motivation: Resting state fMRI (rs-fMRI) provides vital neurological information and mid-field scanners offer easier MRI access. Goal(s): To demonstrate feasibility and reproducibility of rs-fMRI with multi-echo EPI (ME-EPI) acquisition at 0.5 T using a large number of echoes (7) combined with TE-dependent denoising and optimal echo combination. Approach: We acquire repeated ME-_EPI rs-fMRI acquisitions of eleven healthy volunteers, on 2 consecutive days, at 0.5 T, use ICA to capture networks, and assess reproducibility. Results: Spatial consistency of correlated regions within a specific network was seen for both individual volunteers and group data. Dice coefficients > 0.5 and ICC ~0.6. Impact: ME-EPI is feasible for producing reliable rs-fMRI at 0.5 T, potentially expanding access of rs-fMRI in the acute setting.