Perinatal hypoxic/ischemic spinal cord injury.

We have reviewed our experience in 900 consecutive necropsies performed on infants who died in the first 4 weeks of life. The neuropathologic characteristics of acute hypoxic/ischemic spinal cord injury are described in 21 infants who expired in the perinatal period. Several distinct patterns of spinal cord injury were apparent in asphyxiated neonates. Cord infarction, rare in older age groups, was the commonest lesion and was associated with prematurity and with documented episodes of systemic hypotension. Lumbosacral cord segments were more severely affected, and at affected levels central cord parenchyma was completely necrotic with relative sparing of the periphery. Diffuse neuronal necrosis was more typical of infants delivered at or after term. In these neonates ventromedial neurons were most profoundly injured. Hematomyelia dissecting into spinal cord parenchyma was a consequence of germinal matrix hemorrhage in very premature infants. "Watershed zones" in the cord appear to be most severely affected in these infants. The patterns of spinal cord infarction and the association of this lesion with prematurity and systemic hypotension suggest that the absence or failure of spinal cord blood flow autoregulation may play a role in the etiopathogenesis of perinatal hypoxic/ischemic spinal cord injury.