Bidirectional Changes in Anisotropy Are Associated with Outcomes in Mild Traumatic Brain Injury.

Area of Science:

• Neuroimaging
• Neurology
• Biomarkers

Background:

• Mild traumatic brain injury (mTBI) can lead to persistent, heterogeneous deficits.
• Identifying early biomarkers is crucial for predicting long-term outcomes in mTBI patients.

Purpose of the Study:

• To identify early diffusion tensor imaging (DTI) biomarkers of mTBI that correlate with outcomes at one year post-injury.

Main Methods:

• Diffusion tensor imaging (DTI) was performed on 39 mTBI subjects and 40 controls within 16 days of injury.
• Cognitive performance and symptom burden were assessed at one year in 26 mTBI subjects.
• Subject-specific DTI abnormalities and brain-wide white matter measures were analyzed.

Main Results:

• Brain-wide DTI measures (mean radial diffusivity, mean diffusivity, mean fractional anisotropy) significantly associated with memory, and health-related quality of life.
• Abnormally high fractional anisotropy in specific regions (frontal lobe, temporal lobe, cerebellum, thalamus) correlated with better attention, somatic, and emotional postconcussion symptom outcomes at one year.

Conclusions:

• Individualized assessment of DTI abnormalities shows significant relationships with long-term mTBI outcomes.
• Abnormally high fractional anisotropy may serve as an imaging correlate of post-injury compensatory mechanisms, predicting better outcomes.