  Resting-state functional Magnetic Resonance Imaging (fMRI) is a powerful
imaging technique for studying functional development of the brain in utero.
However, unpredictable and excessive movement of fetuses have limited its
clinical applicability. Previous studies have focused primarily on the accurate
estimation of the motion parameters employing a single step 3D interpolation at
each individual time frame to recover a motion-free 4D fMRI image. Using only
information from a 3D spatial neighborhood neglects the temporal structure of
fMRI and useful information from neighboring timepoints. Here, we propose a
novel technique based on four dimensional iterative reconstruction of the
motion scattered fMRI slices. Quantitative evaluation of the proposed method on
a cohort of real clinical fetal fMRI data indicates improvement of
reconstruction quality compared to the conventional 3D interpolation
approaches.
