脳外傷発生メカニズム解明のための実形状頭部物理モデルの構築と脳部変形計測

Abstract

The purpose of this study is to construct a head physical model with actual human shape by using CAD/CAM technologies, in order to clarify head injury mechanism such as diffused axonal injury (DAI) under rotational impact. The head physical model was constructed from CT images of a subject, which consists of the parts reconstructed the skull, falx, cerebrospinal fluid (CSF) and brain. The skull model was processed from the 3D CAD model by using five axis machining. The falx celebri part was attached to the skull model. Moreover, the brain model, including complex structure and shape of the actual human head such as cerebral sulci, gyrus, and ventricles, was constructed by curing silicone gel in the mold processed by stereo-lithography. Finally, the gap between the skull and brain model was filled with water to simulate relative rotational motion of the skull and brain. Severe rotational acceleration corresponding to the occurrence of AIS5 head injury was applied around saggital axis of the model. As the results of the experiments, shear strain concentrated near the corpus callosum in depth of brain, where focal lesion is observed in grade II DAI. The result has not showed in other physical models with simplified the shape and construction. Therefore, a head physical model reconstructed a real human shape is needed to clarify the mechanism of brain injury due to rotational impact.