Quantifying Longitudinal Microstructural Changes in Mild Traumatic Brain Injury Patients with Mean Apparent...

Area of Science:

• Neuroimaging
• Biomarkers
• Medical Physics

Background:

• Mild traumatic brain injury (mTBI) can cause subtle, yet significant, microstructural damage not detected by standard clinical scans.
• Current diffusion MRI techniques have limitations in sensitivity and specificity for assessing mTBI-related tissue alterations.
• Mean apparent propagator MRI (MAP-MRI) offers a more comprehensive assessment of tissue microstructure.

Purpose of the Study:

• To investigate the sensitivity of MAP-MRI-derived quantitative imaging biomarkers in detecting previously undetected microstructural damage in mTBI patients.
• To develop and validate an MAP-MRI data processing pipeline for analyzing longitudinal diffusion-weighted images.
• To compare longitudinal tissue changes in mTBI patients with healthy controls.

Main Methods:

• Developed and validated an MAP-MRI data processing pipeline for diffusion-weighted image analysis.
• Utilized longitudinal scans from the GE/NFL/mTBI MRI database for healthy controls and mTBI patients.
• Performed regional outlier analysis of longitudinal tissue changes over a 90-day observation period.

Main Results:

• Several MAP-MRI-derived parameters exhibited increased intersession variability in white matter tracts and deep gray matter nuclei of mTBI patients compared to controls.
• Longitudinal monitoring revealed evolving pathological changes in mTBI patients.
• Current image-based biomarkers demonstrated insufficient sensitivity and specificity for predicting patient outcomes.

Conclusions:

• Longitudinal monitoring of MAP-MRI metrics provides a comprehensive approach to studying evolving pathological changes in mTBI.
• MAP-MRI shows potential for detecting subtle microstructural damage and tracking disease progression in mTBI.
• This technique may offer improved sensitivity and specificity over current biomarkers for mTBI assessment and outcome prediction.