The relationship between early life EEG and brain MRI in preterm infants: A systematic review

Objective: To systematically review the literature on the associations between electroencephalogram (EEG) and brain magnetic resonance imaging (MRI) measures in preterm infants (gestational age < 37 weeks). Methods: A comprehensive search was performed in PubMed and EMBASE databases up to February 12th, 2024. Non-relevant studies were eliminated following the PRISMA guidelines. Results: Ten out of 991 identified studies were included. Brain MRI metrics used in these studies include volumes, cortical features, microstructural integrity, visual assessments, and cerebral linear measurements. EEG parameters were classified as qualitative (Burdjalov maturity score, seizure burden, and background activity) or quantitative (discontinuity, spectral content, amplitude, and connectivity). Among them, discontinuity and the Burdjalov score were most frequently examined. Higher discontinuity was associated with reduced brain volume, cortical surface, microstructural integrity, and linear measurements. The Burdjalov score related to brain maturation qualitatively assessed on MRI. No other consistent correlations could be established due to the variability across studies. Conclusions: The reviewed studies utilized a variety of EEG and MRI measurements, while discontinuity and the Burdjalov score stood out as significant indicators of structural brain development. Significance: This review, for the first time, provides an extensive overview of EEG-MRI associations in preterm infants, potentially facilitating their clinical application.