Assessment of structural connectivity in the preterm brain at term equivalent age using diffusion MRI and T2...

Area of Science:

• Neuroscience
• Developmental Biology
• Medical Imaging

Background:

• Preterm birth frequently leads to adverse neurodevelopmental outcomes.
• Non-invasive methods are needed to assess neural correlates of these deficits.
• Brain structural network analysis using diffusion MRI and tractography offers a potential solution.

Purpose of the Study:

• To identify altered white matter properties in the structural brain network of preterm infants compared to term infants.
• To investigate the relationship between these alterations and gestational age at birth and postmenstrual age.
• To assess the utility of combining diffusion MRI with T2 relaxometry for evaluating preterm infant brain development.

Main Methods:

• Diffusion MRI and T2 relaxometry data acquired from 18 preterm and 9 term neonates at term equivalent age.
• Probabilistic tractography and the Johns Hopkins neonatal brain atlas used to construct structural brain networks.
• Network-based statistic framework applied to identify connections with altered diffusivity (FA) or T2 values.

Main Results:

• Significant reductions in fractional anisotropy (FA) in 17 connections and increased T2 values in 18 connections were found in preterm infants.
• Affected cortical networks primarily involved left frontal and temporal regions, crucial for higher cognitive functions.
• Gestational age at birth correlated with T2 alterations, but not diffusion measures; no association with postmenstrual age at MRI.

Conclusions:

• Alterations in the structural brain network are detectable in preterm infants at term equivalent age.
• Integrating T2 relaxometry with diffusion MRI provides complementary information for assessing brain development in preterm infants.
• Findings highlight potential imaging biomarkers for neurodevelopmental deficits associated with preterm birth.