Does Subarachnoid Space Protect the Brain From Blast Waves and/or Blunt Impacts?

Abstract

The objectives of this study is to investigate the transduction of blast wave through the SAS region and the influence of SAS including different types of trabeculae in reducing the strain in the brain, when the head is subjected to a blast wave, and finally, comparing that to a none blast load such as blunt impacts or angular accelerations of the head during contact sports or accidents. This is accomplished through a series of Global/Local models of the head, neck and the brain. Specifically, a validated FE 3D model of the head and neck is subjected to a blast wave and the time dependent local compressive pressure gradient on the dura matter is calculated. Then through several detailed local FE models of the head, consisting Dura mater, Gray matter, Subarachnoid space having trabeculae and the CSF, the strains in the brain are calculated. In the local models different architecture and morphology of the trabeculae (rod shaped and the tree-shaped) are considered. The Global/Local models were analyzed using ABAQUS 6.12. In addition, the same procedure has been carried out for a velocity impact profile corresponding to 1.1 mph. The results revealed that the shape of the trabeculae would not affect the severity of loads transferring to the brain from shock waves in blast scenarios. Moreover, the interaction between the CSF and Tree-shaped trabeculae and rods with smaller cross sections, protect the brain better in impacts.