Investigating Cerebrospinal Fluid (CSF) role in Traumatic Brain Injury during External Head Impacts using Fluid-Structure Interaction (FSI) Model

Traumatic Brain Injury (TBI) annually causes significant disability across various age groups. During head impacts, the soft brain tissue, surrounded by cerebrospinal fluid (CSF) within the skull, undergoes substantial motion and deformation. While existing studies have investigated brain tissue strain and stress during impacts, they often treat CSF as a viscoelastic solid, neglecting its fluidic behavior. Hence, the influence of CSF as a fluid on brain tissue motion, deformation, and force transmission from the skull to the tissue remains relatively understudied. To address this gap, our study uses numerical simulations to investigate the interaction between CSF as a fluid and brain tissue as a solid and explore the hypothesis that CSF flow can play a major role in the deformation of brain tissue by analyzing the pressure differences and shear forces induced by the fluid. We investigate how these would impact brain tissue stress and strain and consequently the magnitude and location of the potential damage. This research will advance our knowledge of injury mechanisms by providing insights into the fluid-structure interaction in the head during external impacts.