Correlating Tissue Response with Anatomical Location of mTBI Using a Human Head Finite Element Model under Simulated Blast Conditions

Mild traumatic brain injury (mTBI) has recently been shown to include deficits in cognitive function that have been correlated to changes in tissue within regions of the white matter in the brain. These localized regions show decreased anisotropy in water diffusivity, which are thought to be related to local mechanical damage. However, a specific link to mechanical factors and tissue changes in these regions has not been made. This study is an initial attempt at such a correlation. A human head finite element model, verified against experimental data under simulated blast loading conditions, was used to estimate strains within regions in the brain that are correlated to functional deficits. Strain values from the most anterior and posterior extent of the corpus callosum (the rostrum and the splenium), the right and left anterior and posterior limb of the internal capsule (ALIC and PLIC), and the left cingulum bundle were calculated under frontal blast loading at overpressure intensities below those typically known to cause injury. Strain peaks of approximately 1 percent were noted in regions associated with cognitive brain injury, indicating that loading conditions which involve higher pressures could raise strains to significant levels.