A Novel Fixel-Based Approach for Resolving Neonatal White Matter Microstructure from Clinical Diffusion MRI

Area of Science:

• Neuroimaging
• Developmental Neuroscience
• Medical Physics

Background:

• Preterm birth disrupts neonatal brain development, leading to neurodevelopmental disorders.
• Neonatal brain imaging is challenging due to data quality and immature tissue.
• Current neuroimaging methods often fail with underdeveloped neonatal brains.

Purpose of the Study:

• To develop and validate an advanced diffusion MRI method for assessing white matter microstructure in premature neonates.
• To examine the relationship between white matter development, postmenstrual age, and neonatal illness severity.
• To establish a practical framework for clinical neonatal brain research.

Main Methods:

• Developed a novel diffusion MRI approach resolving multiple tissue compartments.
• Quantified white matter fiber orientation and tissue signal fraction.
• Employed automated segmentation for analyzing key brain tracts and regions.

Main Results:

• Successfully segmented and reconstructed neonatal white matter tracts.
• Demonstrated tract-specific developmental trajectories, with early pathways showing greater organization.
• Found modest, tissue-specific associations between neonatal illness severity and microstructural properties.

Conclusions:

• Advanced microstructural MRI can yield valuable white matter data from clinical scans.
• This method offers a practical approach for studying neonatal brain development in hospital settings.
• Enables early, non-invasive study of vulnerable preterm infants before clinical assessments are feasible.