054. Substitution of Head CT with Rapid Sequence MRI and Skull X-ray in the Evaluation of Non-Accidental Trauma in Children: A Validation Study

Authors: Randaline Barnett, MD

Head CT (HCT) is historically the most common imaging modality in identifying skull fractures and intracranial hemorrhage in suspected non-accidental trauma (NAT) in children. Given risks of ionizing radiation, particularly in young infants, we sought to validate a proposal to image with a rapid sequence MRI and skull x-ray to identify all injuries compared to CT.Methods: We conducted a retrospective analysis of infants who had been suspected of NAT at an academic pediatric hospital from 5/2020 to 8/2021. We identified 27 infants (ages 0-15 months) who had undergone HCT, skull x-ray, and MRI. A neurosurgeon was blinded from all clinical data and radiology interpretations of the skull x-ray and rapid sequences of MRI (T2, SWI, DWI) as they interpreted imaging to identify skull fractures, intracranial hemorrhage, and scalp swelling.
Fracture detection was different for HCT vs MRI with only 7% of infants having a detectable skull fracture on MRI (p=0.0004), but it did not differ between HCT vs x-ray (71%, p=0.9997) or HCT vs x-ray combined with MRI (79%, p=0.9874). Intracranial hemorrhage was better detected on MRI than CT (p= < 0.0001). 100% of infants who had an intracranial hemorrhage on CT had hemorrhage on MRI while 33% without hemorrhage on CT had an intracranial hemorrhage on MRI. When a scalp hematoma was present on MRI, 79% had an associated skull fracture (11/14) (p= < 0.001), and in infants who did not have a skull fracture on CT, 0% had a scalp hematoma on MRI (p= < 0.001).
While skull fractures are better detected on CT, there is no difference between their detection on CT vs x-ray or CT vs x-ray/MRI, and MRI provides superior detection of intracranial hemorrhage, suggesting the use of skull x-ray combined with MRI is an acceptable alternative for detection of NAT related injuries without additional HCT radiation.