Development of a finite element model analysing traumatic brain injury for forensic medicine

三维有限元（FEM）人体头部模型(6)。6公斤)由皮肤、颅骨和颅内物质（CSF）组成。采用MRI对皮肤和颅内物质（CSF）成像，CT对颅骨成像制作头部模型。该头部模型配有颈部有限元模型（750g）和人体有限元模型（60kg）。模型各部分（皮肤、颅骨、脑脊液）的材料属性均采用文献资料。利用个人计算机和LS-TC公司的LS-Dyna有限元程序，计算了击打和跌落实验中脑卒中侧和脑卒中对侧的颅内压响应。在500g啤酒瓶以7m/sec的速度撞击头部模型额部的冲击实验中，计算出重击侧负颅内压响应为105kPa，重击侧为207kPa。另一组600kg铁质重箱以1m/s的速度撞击枕区，15kPa负颅内压响应，撞击侧颅内压响应更大，撞击侧颅内压响应为131kPa。在跌落实验中，模型从10m的高度跌落到铁甲板上，头部枕区碰撞（5m/sec）。创口侧计算30kPa负颅内压响应，创口侧计算1910kpa负颅内压响应。我们从皮质灰质、额叶髓质白质、胼胝体和脑桥的福尔马林固定组织样本中提取总RNA。这些样本是在对因交通事故死亡的头部损伤受试者（生存时间：2.5小时- 10天）进行尸检后获得的。巢式RT-PCR分析使我们能够从所有这些福尔马林固定的脑组织中检测β-APP mRNA。β-APP mRNA在皮层灰质和胼胝体中的表达明显高于白质。在用β-APP抗体对这些样本进行免疫组化研究时，我们仅在生存时间为2.5小时的病例中检测不到。少

A three dimensional finite element (FEM) human head model (6. 06kg) consists of skin, skull and intracranial substance (CSF). The head model is made using the image of MRI for skin and intracranial substance (CSF), and CT for skull. This head model is equipped with a neck FEM model (750g) and a human body FEM model (60kg). Material properties of each part of the model (skin, skull and CSF) are adopted from the literature previously published. We used personal computer and finite element code LS-Dyna made by LS-TC Co. to calculate the intracranial pressure responses in the stroke side and the opposite side of stroke in a blow and a fall experiments. In the blow experiment in which 500g beer bottle collided (7m/sec) with the frontal region of the head model, 105kPa negative intracranial pressure response was calculated in the coup side and 207kPa in the contrecoup one. In the other blow experiment in which 600kg iron heavy box collided (1m/sec) with the occipital region, 15kPa negative i … More ntracranial pressure response was done in the coup side and 131kPa in the contrecoup one. In the fall experiment, the model fell on the iron deck from the height of 10m and the occipital region of the head collided (5m/sec). 30kPa negative intracranial pressure response was calculated in the coup side and 1, 910kPa in the contrecoup one.We extracted total RNA from formalin-fixed tissue samples of the cortical gray matter, medullary white matter of the frontal lobe, corpus callosum, and pons. These samples had been obtained after autopsy of head-injury subjects who died (survival period : 2.5 hours - 10 days) due to vehicular accidents. A nested RT-PCR analysis enabled us to detect β-APP mRNA from all of these formalin-fixed brain tissues. The expression of β-APP mRNA in the cortical gray matter and corpus callosum was increased compared with that in white matter. In the immunohistochemical studies on these samples with β-APP antibody, we couldn't detect only in the the case whose survival period was 2.5 hours. Less