Multi-Echo fMRI Analysis of the Fetal Brain at 0.55T

Motivation: Low field MRI carries essential benefits such as reduced distortions for fetal MRI. But reduced SNR is a key problem particularly for fMRI, dependent on a sufficient BOLD-signal. Using multiple echoes may compensate for reduced SNR, improving the available BOLD-signal for fMRI. This can yield higher-quality fetal MRI and facilitate enhanced functional assessment of fetal neurodevelopment. Goal(s): This study extends the SVRTK-pipeline for automated 3D-T2*-reconstructions to include ME-fMRI. Approach: Multi-echo-gradient-EPI scans were obtained at 0.55T from 250 fetuses and processed through the pipeline. Results: Automated spatiotemporal alignment and labeling of the fetal brain was successfully performed, enabling subsequent ME-fMRI to identify independent components. Impact: The reduced SNR for fMRI at 0.55T can be compensated by ME-fMRI. This study explores the feasibility of ME-fMRI of the fetal brain, paving the way for future research and clinical usage.