颅脑接触面不同设置以及脑脊液单元划分密度对脑组织动态响应的影响

Effects of Dynamic Brain Response under Different Setting of Skull-Brain Interface and Mesh Density Division of Cerebrospinal Fluid

目的 探讨颅脑接触面不同定义方式和脑脊液(cerebrospinal fluid,CSF)单元划分密度对脑组织动态响应的影响。方法 基于第50百分位成人头部有限元模型,通过重构尸体直线撞击试验和旋转试验,将颅骨、CSF和脑组织之间定义为共节点、固连和滑动不分离接触面,研究不同接触面类型对脑组织动态响应的影响;颅骨、CSF和脑组织实现共节点接触,将CSF划分为1层和3层六面体单元并保持厚度不变,研究不同CSF划分密度对脑组织动态响应的影响。结果 颅内压力对不同接触面类型较敏感,但脑组织响应对不同CSF单元的划分层数不敏感。结论 研究结果对头部有限元模型中CSF构建以及颅脑接触界面的选择提供理论参考。

Objective To explore the effects of different skull-brain interfaces and mesh density of the cerebrospinal fluid(CSF)on dynamic responses of the brain.Methods The impact kinematics on cadaver head under rotation and translation impacts were reconstructed based on the 50th percentile adult head finite element model.The interfaces between skull and CSF,CSF and brain were modeled with different types of interfaces,which were set as sharing nodes,tied,frictionless sliding,so as to investigate the effect of different interface types on dynamic responses of the brain.Then,the interfaces between CSF,skull and brain were set as sharing nodes,while CSF was divided into single-layer and tri-layer of hexahedral element with the constant thickness of CSF,to study influences of CSF with different mesh density layers on dynamic responses of the brain.Results The intracranial pressure was highly sensitive to the interface types,while the brain response seemed to be relatively insensitive to the variation in CSF layers.Conclusions The research findings provide theoretical references for the construction of CSF and the selection of skull-brain contact interface of the head finite element model.