Brain tissue microstructural and free-water composition 13 years after very preterm birth

Area of Science:

• Neuroscience
• Radiology
• Developmental Pediatrics

Background:

• Children born very preterm often experience neurodevelopmental difficulties.
• Previous research focused on white matter microstructure, with less attention to free-water content and grey matter in this population.
• Brain biophysical properties change rapidly during early development, making them vulnerable to preterm birth.

Purpose of the Study:

• To investigate the long-term effects of very preterm birth on white matter and cortical grey matter microstructure and free-water content in childhood.
• To correlate these brain alterations with neonatal abnormalities and later neurodevelopmental outcomes.

Main Methods:

• Advanced diffusion MRI analyses were performed on 130 very preterm children and 45 full-term controls at age 13.
• Single-Shell 3-Tissue Constrained Spherical Deconvolution was used to derive diffusion tissue signal fractions.
• Voxel-based and region-of-interest analyses examined brain tissue microstructural and free-water composition.

Main Results:

• Very preterm children showed reduced white matter microstructural density and increased free-water content globally.
• Alterations in microstructural density and free-water content were also observed in specific cortical regions (temporal, frontal, occipital, cingulate).
• These brain composition changes were associated with neonatal white matter abnormalities and adverse cognitive/motor outcomes.

Conclusions:

• Very preterm birth leads to persistent brain microstructural and free-water alterations evident up to age 13.
• These long-term brain changes are linked to neonatal abnormalities and contribute to adverse neurodevelopmental outcomes in very preterm children.
• The study highlights the importance of assessing both microstructure and free-water content in grey and white matter for understanding the impact of preterm birth.