Perinatal Events and Early Magnetic Resonance Imaging in Therapeutic Hypothermia

Objective To 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 design We 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. Results Neonates 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% Cl, 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. Conclusions These results validate reports of reduced brain injury after therapeutic hypothermia and suggest that perinatal factors are important indicators of response to treatment. (J Pediatr 2011; 158:360-5).