Robust preprocessing for stimulus-based functional MRI of the moving fetus.

Publication Type	Academic Article
Authors	You W, Evangelou I, Zun Z, Andescavage N, Limperopoulos C
Journal	J Med Imaging (Bellingham)
Volume	3
Issue	2
Pagination	026001
Date Published	04/05/2016
ISSN	2329-4302
Abstract	Fetal motion manifests as signal degradation and image artifact in the acquired time series of blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) studies. We present a robust preprocessing pipeline to specifically address fetal and placental motion-induced artifacts in stimulus-based fMRI with slowly cycled block design in the living fetus. In the proposed pipeline, motion correction is optimized to the experimental paradigm, and it is performed separately in each phase as well as in each region of interest (ROI), recognizing that each phase and organ experiences different types of motion. To obtain the averaged BOLD signals for each ROI, both misaligned volumes and noisy voxels are automatically detected and excluded, and the missing data are then imputed by statistical estimation based on local polynomial smoothing. Our experimental results demonstrate that the proposed pipeline was effective in mitigating the motion-induced artifacts in stimulus-based fMRI data of the fetal brain and placenta.
DOI	10.1117/1.JMI.3.2.026001
PubMed ID	27081665
PubMed Central ID	PMC4821892