Punctate White Matter Abnormality in Moderate-to-Late Preterm Infants

Area of Science:

• Neonatal neurology
• Neuroimaging
• Developmental neuroscience

Background:

• Moderate-to-late preterm (MLP) infants represent a significant proportion of children with neurodevelopmental impairments.
• White matter injury (WMI) is a known predictor of adverse outcomes in very preterm (VP) infants, but WMA in MLP infants is poorly understood.

Purpose of the Study:

• To investigate the prevalence, burden, and topographical distribution of white matter abnormality (WMA) in moderate-to-late preterm (MLP) infants.

Main Methods:

• Brain MRI was performed on MLP infants shortly after birth and at term-equivalent age (TEA).
• Manual segmentation of WMA was conducted, calculating total and regional volumes and percentage of WMA relative to total cerebral volume.
• Probabilistic WMA maps were generated and compared with WMI in VP infants and term infants with congenital heart disease.

Main Results:

• Of 101 MLP infants, 39.6% exhibited WMA on at least one MRI scan.
• In infants with WMA, lesions often decreased in visibility or became undetectable between early-life and TEA scans.
• Probabilistic mapping revealed a distinct WMA topology, predominantly in posterior brain regions, with trigonal areas showing vulnerability across neonatal populations.

Conclusions:

• White matter abnormality (WMA) is more prevalent in moderate-to-late preterm infants than previously recognized and follows a characteristic distribution.
• WMA may be subtle or missed on term-equivalent age MRI scans.
• The clinical significance and relationship of WMA with neurodevelopmental outcomes in MLP infants require further investigation.