Restricted diffusion in the corpus callosum in hypoxic-ischemic encephalopathy.

Restricted diffusion within the splenium of the corpus callosum was described in various conditions, but is not a prominent finding in magnetic resonance imaging after neonatal hypoxic-ischemic encephalopathy. Perinatal characteristics were reviewed in 42 term neonates with hypoxic-ischemic encephalopathy treated with selective head cooling. Neonatal images of 34 infants were reviewed. Ten of 34 (29%) infants demonstrated restricted diffusion changes within the splenium of the corpus callosum, with a significantly higher incidence of death or severe developmental delay, compared with infants without changes in the splenium of the corpus callosum (n = 24) (P = 0.002). The positive predictive value of changes in the splenium of the corpus callosum regarding poor outcomes or death was 90%. Changes in the splenium of the corpus callosum were also associated with lower birth weights, larger base deficits in cord arterial gas, and more severe encephalopathy during enrollment in selective head cooling. Restricted diffusion within the splenium of the corpus callosum of term infants with hypoxic-ischemic encephalopathy is often associated with extensive brain injury, and in these circumstances appears to be an early neuroradiologic marker of adverse neurologic outcomes.