Study On The Correlation Between Neonatal Hypoxic-ischemic Encephalopathy (HIE) And Head Growth

Objectives: The aims of the study were to find out the relationship between head growth in the first year of life and the pattern of injury on neonatal computerized tomography (CT) in infants with hypoxic-ischemic encephalopathy (HIE) and their effects on the neurodevelopmental outcome.Methods: One hundred and eighteen term neonates who suffering from neonatal HIE and who had brain CT scan were entered into the study. Head circumference charts were evaluated retrospectively and the head growth during the first year of life were compared with the pattern of brain lesions on CT and with the neurodevelopmental outcome at 1 year of age. Suboptimal head growth was classified as a drop of >2 standard deviations across the percentile with or without the development of microcephaly, which was classified as a head circumference below the third percentile.Results : There was no statistical difference of neonatal head circumferences between neonates with HIE and the controls. At 12 months, microcephaly was present in 12.5% of the neonates with HIE, compared with 2% of the controls. Suboptimal head growth was documented in 25% of the neonates with HIE, compared with 3% of the controls. Suboptimal head growth was significantly associated with the pattern of brain lesions, in particular to involvement of severe extentive white matter and to severebasal ganglia and thalamic lesions. Suboptimal head growth predicted abnormal neurodevelopmental outcome with a sensitivity of 77% and a specificity of 91%, compared with the presence of microcephaly at 1 year of age, which had a sensitivity of only 42% and a specificity of 96%. The exceptions were explained by neonates with only moderate white matter abnormalities who had abnormal suboptimal head growth but normal outcome at 1 year of age and by neonates with moderate basal ganglia and thalamic lesions only who had normal head growth but significant motor abnormality.Conclusions: Antepartum risk factors accounts for the majority of neonatal encephalopathy in full-term infants. The mostly type of cerebral palsy associated with intrapartum hypoxia is spastic quadriplegia. We found that suboptimal head growth is a better predictor of neurodevelopmental outcome than the presence of microcephaly alone at the age of 12 months. Infants who have suboptimal head growth but normal development at 1 year of age need to be closely followed up,because assessment at 1 year of age primarily measures motor items and cognitive, perceptual, or minor neurological signs might become obvious later in childhood.