Purpose: To determine the prevalence of parenchymal brain microhemorrhages (MHs) in infants with nonaccidental trauma (NAT) by using susceptibility-weighted (SW) magnetic resonance (MR) imaging and to assess whether the presence of MH results in improved prediction of the long-term neurologic outcome.
Materials and methods: A retrospective case-control analysis of the data for 101 children aged 1-32 months with forensic pediatric specialist-confirmed NAT was performed with institutional review board approval. Sixty-two patients were boys (mean age, 8.4 months +/- 7.4 [standard deviation]), and 39 were girls (mean age, 7.4 months +/- 7.8). The imaging findings and clinical data of the children who were examined with SW imaging were collected. Exclusion criteria included pre-existing cognitive delays, central nervous system malformations, previous brain injuries, and/or birth before 30 weeks gestation. Dichotomized long-term neurologic outcomes (good [normal, mild disability, or moderate disability] versus poor [severe disability, vegetative state, or death]) at greater than or equal to 6 months (mean, 33 months; range 6-95 months) were available for 53 patients (36 boys [mean age, 7.3 months +/- 5.9]; 17 girls [mean age, 7.4 months +/- 7.9]; overall range, 2-32 months). Logistic regression was used to determine whether the presence of SW imaging-depicted MH, as compared with other radiologic findings, resulted in improved prediction of long-term neurologic outcome.
Results: Imaging findings showed that of the 101 patients, 29 (29%) had MH at SW imaging, 66 (65%) had extraaxial hemorrhages, 52 (51%) had retinal hemorrhages, and 35 (35%) had evidence of acute ischemic injury. A significantly larger number of children with poor outcomes than children with good outcomes had brain MH (nine of 14 vs seven of 39; P = .001) and ischemic injury (13 of 14 vs 17 of 39; P = .006). Logistic regression analysis revealed presence of MH at SW imaging-followed by acute ischemic injury, initial Glasgow Coma Scale score, and age-to be the most significant single variable in the final model, with an overall predictive accuracy of 92.5%.
Conclusion: Presence of intraparenchymal brain MH in children with NAT, as detected on SW images, correlates with significantly poor long-term neurologic outcome, improves outcome prediction compared with the predictions made by using other tested clinical and imaging findings, and is most predictive when combined with presence of ischemic injury.