A Visco-Hyperelastic Model for Prediction of The Brain Tissue Response and The Traumatic Brain Injuries

Abstract

Background: Numerous geometrically simplified models may be found in literature for simulation of the traumatic brain injuries due to the increased intracranial pressure caused by sever translational accelerations of the brain inside the cranium following the impact waves. Some researchers have used a more accurate model but employed a specific hyperelastic material model. No research has presented a comprehensive comparison among results of various geometric and hyperelasticity models, so far. Methods: In the present research, two distinct finite element models and four hyperelastic constitutive models (i.e., polynomial, Yeoh, Arruda-Boyce, and Ogden models) are employed to accomplish the mentioned task. Therefore, the motivation is checking accuracy of the modeling procedure rather than presenting clinical results. In this regard, a realistic skull-brain model is reconstructed in CATIA software based on the MRI scans and employed for optimized mesh generation in HYPERMESH finite element software. Results: Influence of the contact and nonlinear characteristics of the brain tissues are considered in simulation of the relative motions in LS-DYNA software. Finally, time histories of the accelerations and the pressures (stresses) are derived from ANSYS finite element analysis software. Discussion: Comparisons made with the available experimental results for the four hyperelastic constitutive equations confirm that employing Arruda-Boyce or Ogden models may lead to inaccurate or even erroneous results.