The aim of the present study is to determine if abnormalities in the splenium of the corpus callosum in neonates with hypoxic ischemic encephalopathy (HIE) are also predictive of seizures.  

We performed a retrospective chart review of 144 neonates who had a diagnosis of HIE and underwent MRI within the first 10 days of life.  The areas examined for injury include the splenium, other corpus callosum, gray matter, deep gray matter, and subcortical white matter. APGAR scores and pH, two important markers of hypoxia and encephalopathy, were also analyzed in relation to MRI abnormalities.

Approximately 50% of the neonates had at least one abnormal area on brain MRI, and 18% had abnormality in the splenium. Confirmed electrographic seizures were documented in 38%. Changes in the splenium had sensitivity = 42%, specificity = 97%, positive predictive value (PPV) = 88% for seizure. Seizure was associated with changes in all brain regions examined, whereas APGAR at 10 minutes was associated with changes in gray matter (chi square, χ² = 6.1, P<0.05) and subcortical white matter (χ² = 6.9, P<0.05), and pH was not associated with any abnormality.

The splenium is specific and predictive for seizures in neonates with HIE. Seizures represent a risk factor for brain injury in all brain areas studied, whereas low APGAR represents a risk factor for injury in only gray and subcortical white matter. These results validate reports of the splenium being suggestive of recent seizures and reinforce seizure as an important indicator of increased severity in HIE.