Rat brain injury mechanism identification through indentation experiment FE reconstruction

The rat head Finite Element Model of the Strasbourg University is composed of three main features: a brain, a rigid skull and a layer of solid elements figuring the interface between the former two features. In order to simulate indentation, a cylinder was meshed and added to the original model. The lower part of the cylinder was positioned so as to match the position of the indentor in the experimental setup. Dimensions and mass of the cylinder matched those of the real impactor. The orientation of the main axis of the cylinder was chosen in order to improve the region of contact between the cylinder and the brain. On the external surface of the head mesh, elements from the skull components were removed in order to represent the craniotomy act and exposed the underlying cerebral matter. Two cases were made. The first one for the mild level of impact (penetration depth 0.87 mm) and the second one for the severe level (penetration depth 2.62 mm). In both cases, observed injuries were compared to calculated mechanical parameters such as brain pressure, brain shearing stress, brain strain. That correlation attempt led to brain injury mechanism identification.

 

The Author

Dr. Daniel Baumgartner
Associate Professor
University of Strasbourg