Neuropathologic study of newborns with prenatal-onset leukomalacia.

The distribution of leukomalacia and glial fibrillary acidic protein (GFAP)-positive glial cells in prenatal- and postnatal-onset leukomalacia were compared and diagnosed histologically in 128 autopsied infants and the different pathogeneses were examined. Prenatal-onset leukomalacia was diagnosed in 12 of 71 still-births and neonates surviving less than 3 days (16.9%). All 4 preterm infants of less than 32 gestational weeks had widespread white matter necrosis and 4 of 5 term infants had focal necrosis. GFAP-positive glial cells were more increased in the deep and intermediate white matter in both forms of leukomalacia than in the controls, although in the subcortical white matter they were less increased in prenatal- than postnatal-onset leukomalacia. These differences may indicate different pathogeneses, including vascular maturity and causal factors, in prenatal- and postnatal-onset leukomalacia.