Viscoelastic finite-element analysis of human skull - dura mater system as intracranial pressure changing

Abstract

In the work, the dynamic characteristics of the human skull-dura mater system were studied. For the purpose of our analysis, we adopted a model consisted of a hollow sphere. By using the ‘Patran and
Ansys’ finite element processor, a simplified three-dimensional finite element model (FEM) of a human skull was constructed. The model was used to calculate the deformation of human skull with the intracranial pressure changing. This required good representation of the complex anatomy of the skull. Four different entities are distinguished: Tabula externa, Tabula interna, and a porous Diploe sandwiched in between, and dura mater. A thin-walled skull was simulated by composite shell elements. The viscoelasticity of human skull-dura mater system was studied and analyzed by the finite-element Maxwell model. The 1/8 model consisted of 25224 nodes and 24150 three-dimensional 8-node
isoparametric solid elements. The elastic-viscous mechanical characteristics must be used for the skull. The viscous strains account for about 40% of total strains of human skull and dura mater. And the
range of strain errors is from 6.45 to 14.82% after ignoring the viscosity of skull and dura mater.