Neuroimaging allows us to see inside the human brain, and researchers say the technique and a new understanding of certain biomarkers may help predict which patients have a better chance of recovery after a mild traumatic brain injury.
The findings suggest that patients with abnormally high fractional anisotropy (FA), as viewed on diffuse tensor imaging (DTI) at the time of their injury, were more likely to have a better recovery outcome. Now that last sentence was filled with some technical medical language, but we’ll do our best to help explain what it all means. Fractional anisotropy is a measure of microstructural organization, in that is allows us to better understand structural connectivity in the brain.
“It’s a feature of what is sometimes called structural connectivity, but it per se does not really speak to the functionality of the connection but speaks to the presence of normally structured white matter,” said Dr. Michael Lipton, lead author of the study.”
For their research, scientists examined brain activity and biomarkers in 39 adult patients evaluated at an emergency department and diagnosed with a concussion within 48 hours of injury. They also took the same data from 40 healthy and non-concussed volunteers. Researchers examined nine white matter regions in the brain known to be susceptible to mild traumatic brain injuries and/or linked to functions associated with mild TBI morbidity. These locations included the:
- Left and right frontal lobe
- Left and right temporal lobe
- Left and right thalamus
- Left and right cerebellum
- The corpus callosum
Researchers effectively created a “brain map” to check for levels of abnormally high FA or abnormally low FA in all nine of these regions. The team created a baseline score and then reassessed the patients at one year post injury, also testing for symptom prevalence, executive function, memory and attention.
TBI Study Results
After examining the data, researchers uncovered:
- When looking at attention scores, those with abnormally high FA scores in the left frontal lobe or the left temporal lobe performed significantly better than those with low FA scores.
- Participants with high FA in the right thalamus has significantly fewer emotional postconcussive symptoms than those with low FA.
- Individuals with high FA in the left cerebellar white matter and those with high FA in the right cerebellar white matter had significantly fewer somatic postconcussive symptoms.
“We found that the presence of abnormally high FA was a predictor of better outcome,” said Dr Lipton, noting that better outcomes weren’t just isolated to cognitive functions, but also for “emotional function and what we call health-related quality of life.”
Dr. Lipton’s team theorized that abnormally high levels of FA in the brain may represent evidence of the brain compensating for the injury.
“The way the brain recovers from, or responds to, injury is through mechanisms like neuroplasticity,” said Dr Lipton. “What we are proposing here is that the areas of high FA that we are seeing may actually represent areas of compensatory or neuroplastic responses, not the actual injury itself.”
He concluded by saying the study results may change the way we diagnose, treat and manage head injuries after concussions or traumatic brain injuries.
“Developing an effective intervention requires first identifying the people who need it.”