Cortical Sparing in Preterm Ischemic Arterial Stroke

Background and Purpose-Residual injury after perinatal arterial ischemic stroke in the middle cerebral artery territory usually involves the loss of cortical gray matter and subcortical white matter. In this article, we describe a different pattern of residual injury after middle cerebral artery stroke in preterm-born infants, in which the cortex is spared.

Methods-Magnetic resonance imaging scans of 40 infants (12 preterm and 28 full-term infants) with a large middle cerebral artery stroke were reviewed and correlated with outcome.

Results-Complete sparing of the cortex with cavitation of the underlying white matter was observed in 3 preterm infants, and partial sparing was noted in another 4 late preterm-born infants. One full-term infant had partial cortical sparing, and all others showed no sparing. Overall, 86% developed a hemiplegia and 30% had a developmental quotient below 85, but this did not vary between the different types of cortical injury.

Conclusions-The pattern of cortical injury after middle cerebral artery stroke changes with gestational age and may be related to maturational changes of the vascular system. Outcome did not vary between the different patterns of cortical injury.