Clinical predictors of intracranial injuries on CT in infants younger than 2 years old with mild traumatic brain injury

Purpose Mild traumatic brain injury (TBI) is common in children. The aim of this study was to identify clinical predictors of intracranial injuries on computed tomography (CT) in infants younger than 2 years old with mild TBI, which allow reducing number of imaging. Results Of 214 enrolled infants with complete data, 30 (5.8%) sustained intracranial injuries. Younger age in months, severe injury mechanism and scalp hematomas were associated with traumatic intracranial injuries on CT. 71 had scalp hematomas and 143 had no scalp hematoma. Within infants with scalp hematomas, 26 sustained intracranial injuries and 45 presented normal. Intracranial injuries were significantly correlated with larger scalp hematomas and different scalp hematoma locations. Logistic regression analysis showed that scalp hematoma and mechanism of injury in infants younger than 2 years old with mild TBI was related to intracranial injuries (hazard ratio=38.291, P=0.0001; hazard ratio=0.174, P=0.001). In subgroup of mild TBI infants with scalp hematomas, logistic regression analysis showed age, scalp hematoma size and mechanism of injury were independently associated with intracranial injuries (hazard ratio=0.299, P=0.032; hazard ratio=5.272, P=0.006; hazard ratio=0.312, P=0.030). Methods Between 2014 and 2016, we retrospectively enrolled infants <2 years old with mild TBI. Data recorded included age, sex, mechanism of head injury, size and location of scalp hematoma, fracture and intracranial injuries on CT. Conclusion The characteristics of scalp hematomas and mechanism of injury were associated with intracranial injuries. These factors should be considered when making decisions on radiologic examinations of infants < 2 years old with mild TBI and alternative procedures, which do not involve ionizing radiation, should be used if appropriate.