CT scans are commonly used to diagnose traumatic brain injury (TBI) in young children; however, this is a significant source of ionizing radiation and often anesthesia is required.
In a prospective cohort study published in the journal Pediatrics, researchers discovered that fast MRI – which does not require the child to be motionless or sedated like conventional MRI – is able to accurately test for TBI.
The team of scientists from the University of Colorado School of Medicine (CO, USA) carried out fast MRI in children under the age of 6 years who had already had head CT scans performed following head trauma. The researchers measured accuracy of the fast MRI by comparing against CT findings of TBI, such as skull fractures, intracranial haemorrhages and parenchymal injuries.
A total of 223 participants successfully had both scans within 24 hours of each other so the child’s condition would not change significantly. TBI was identified by CT in 111 whilst fast MRI identified TBI in 103, missing six isolated skull fractures and two subarachnoid hemorrhages. The team calculated fast MRI’s sensitivity to be 92.8% but had previously set 95% as the target to be considered useful.
In the paper authors wrote:
Although the sensitivity of fast MRI did not meet our pre-specified threshold, we feel that the benefit of avoiding radiation exposure outweighs the concern for missed injury.”
Authors noted that the injuries missed by fast MRI are rarely treated, furthermore, fast MRI found cases of TBI that CT did not – for example, two injuries were detected in one child.
The team of researchers also reported that median imaging time was 59 seconds for the CT scans and 365 seconds for fast MRI, suggesting that fast MRI was also a feasible method.
The authors added:
The ability to complete imaging in ~6 minutes, without the need for anesthesia or sedation, suggests that fast MRI is appropriate even in acute settings where patient throughput is a priority.”
The results from this paper suggest great potential for the use of fast MRI in TBI diagnosis, however, the study is limited by the fact only clinically stable children were used. Therefore, in future more generalizable studies are required to confirm the suitability of fast MRI for acutely head-injured children.
Sources: Lindberg DM, Stence NV, Grubenhoff JA et al. Feasibility and accuracy of fast MRI versus CT for traumatic brain injury in young children. Pediatrics. doi:10.1542/peds.2019-0419 (2019) (Epub ahead of print); www.aappublications.org/news/2019/09/18/fastmri091819