MRI Detects More Areas of Brain Injured in Concussions

Magnetic resonance imaging detects regional white matter damage in patients with mild traumatic brain injury (TBI) and vestibulopathy, according to a study published in the journal Radiology.

Researchers from the University of Pittsburgh Medical Center in Pennsylvania performed a study to determine if central axonal injury underlies vestibulopathy and ocular convergence insufficiency after mild TBI. Vestibulopathy is one of the most common and debilitating effects of concussions, or mild TBIs.

The researchers retrospectively reviewed imaging data from 55 patients with mild TBI – 30 of whom had vestibular symptoms and 25 who had ocular convergence insufficiency. There were 39 controls with mild TBI but who did not have vestibular difficulties and 17 with mild TBI with normal ocular convergence. Imaging was acquired by diffusion tensor imaging (DTI). Fractional anisotrophy (FA) maps were generated as a measure of white matter integrity and were analyzed with tract-based spatial statistics (TBSS) regression analysis.

“FA provides a measure of how intact the white matter is,” co-author Lea Alhilali, MD, said in a release. “The lower the FA value, the more injured the white matter is.”

The findings showed that the patients with mild TBI with vestibular symptoms also had decreased FA values in the cerebellum and fusiform gyri, regions of the brain that had not previously been suspected to be involved in post-traumatic vestibulopathy. “Patients with vestibular symptoms had white matter injury in the cerebellar area, which is known to control balance and movement, and also in the fusiform gyri, a brain area that integrates the visual fields of the left and right eye, and is important to spatial orientation,” Alhilali explained.

Patients with ocular convergence insufficiency were found to have diminished neurocognitive test scores and FA value in the right anterior thalamic radiation and right geniculate nucleus optic tracts. “Cerebellar injury showed an inverse correlation with recovery time,” the study authors wrote. “Anterior thalamic radiation injury showed correlation with decreased processing speed.”

The authors concluded that the findings appeared to show a connection between vestibulopathy and regional brain damage among patients with mild TBI. Results of DTI could eventually be used alongside neurocognitive testing to help determine a patient’s prognosis and to allow for appropriate treatments.