Relationships between early postnatal cranial ultrasonography linear measures and neurobehaviour at term-equivalent age in infants born <30 weeks' gestational age

Background: The relationship between early postnatal brain development and neurobehaviour at term-equivalent age (TEA) remains uncertain. Aim: We aimed to explore relationships between early postnatal cranial ultrasonography (cUS) linear measures of brain size and brain growth with neurobehaviour at TEA in infants born <30 weeks' gestational age (GA). Study design: Prospective observational cohort study. Subjects: 137 infants born <30 weeks' GA without major brain injury on neonatal cUS. Outcome measures: Neurobehaviour at TEA assessed using the General Movements Assessment (GMA) and Hammersmith Neonatal Neurological Examination (HNNE). Results: The GMA was administered in 115/137 (84%) infants; 80 (70%) presented with abnormal general movements (GMs) (79 poor repertoire, 1 cramped synchronised). The HNNE was assessed in 106/137 (77%) infants; 52 (49%) had a suboptimal total score. With respect to brain size, larger measures of the corpus callosum length (CCL) and right anterior horn width (AHW) at 1-month were related to lower risk of abnormal GMs, and larger measures of the biparietal diameter at 1-week and 2-months were related to lower risk of a suboptimal HNNE. As for brain growth, increases of the CCL and transcerebellar diameter between birth and 1-month, and left and right AHWs between 1- and 2-months, were related to lower risk of abnormal GMs. Conclusion: Early postnatal brain size and brain growth were related to neurobehaviour at TEA in infants born <30 weeks' GA. This study provides preliminary evidence for the prognostic utility of early postnatal cUS linear measures as potential markers of neurodevelopment in later childhood.