Perinatal Events and Early Magnetic Resonance Imaging in Therapeutic Hypothermia

ObjectiveTo compare the association between perinatal events and the pattern and extent of brain injury on early magnetic resonance imaging in newborn infants with and without therapeutic hypothermia for hypoxic-ischemic encephalopathy.Study designWe performed a cohort study of 35 treated and 25 nontreated neonates who underwent magnetic resonance imaging. The injury patterns were defined a priori as: normal, watershed, or basal ganglia/thalamus-predominant, as well as a dichotomous outcome of moderate-to-severe versus mild-no injury.ResultsNeonates with hypothermia had less extensive watershed and basal ganglia/thalamus injuries and a greater proportion had normal imaging. Therapeutic hypothermia was associated with a decreased risk of both basal ganglia/thalamus injury (relative risk, 0.29; 95% CI, 0.10 to 0.81, P = .01) and moderate-severe injury. Neonates with sentinel events showed a decrease in basal ganglia/thalamus-predominant injury and an increase in normal imaging. All neonates with decreased fetal movements had injury, predominantly watershed, regardless of therapeutic hypothermia.ConclusionsThese results validate reports of reduced brain injury after therapeutic hypothermia and suggest that perinatal factors are important indicators of response to treatment.