Mouse Brain Microstructural Changes by High-resolution Diffusion Magnetic Resonance Imaging and Spatial Transcriptomics During Development

Motivation: Characterizing developmental brain microstructure changes is important for understanding the mechanism of brain development at cellular level. Goal(s): We aimed to study brain microstructure and to correlate phenotypical diffusivity variations with genotypic expression profiles. Approach: We imaged postnatal mouse brains by high-resolution diffusion magnetic resonance imaging (dMRI) with both DTI and NODDI models to extract quantitative diffusion metrics. dMRI-gene expression correlation was tested by regression model. Results: Distinct growth patterns are observed by quantitative dMRI parameters in white matter bundles, isocortex, hippocampus, and cerebellum. Genes related to nerve system displayed unique spatial and temporal expression patterns corresponding with dMRI alternations during brain development. Impact: This study may improve our understanding of brain microstructure changes during postnatal development at molecular and cellular level. This study also provides non-invasive imaging techniques to quantitatively investigate neurodevelopmental disorders at high resolution.