Analyzing the changes in the brain material properties after a mild traumatic brain injury-A pilot study

Traumatic brain injury (TBI) is a major health challenge, is very difficult to diagnose, and currently has no accepted treatment options. The difficulty in diagnosis is due to the complex pathophysiology of TBI, where the damage mechanisms span multiple spatial and temporal scales and ultimately manifest as diverse cognitive impairments in brain function. The speed and dynamic nature with which the mechanical insults occur in TBI means that computational models are the best candidate to mimic the in vivo event and to investigate the injury progression in detail. A current weakness in TBI computational models is the poor understanding of how material properties within different regions of the brain change after damage. Here, we developed an animal experiment pipeline where a controlled and reproducible mechanical insult can be applied to a sheep brain in vivo followed by ex vivo compression mechanical testing. For each brain, the compression mechanical testing was conducted across the length of the brain to assess baseline regional variations in material properties and how these properties changed after mechanical impact. Using this pipeline, we have characterized locational variations in the brain material properties both pre and post-TBI. Our preliminary results confirm that there exist locational variations in the brain material properties across all regions of cerebrum. The analysis of post-TBI tissues showed that compressive strength was reduced in the area nearest the direct impact.