EXPERIMENTAL DIFFUSE AXONAL INJURY

因为创伤性损伤对轴突和弥漫性损伤的重要性 具体为轴索损伤(DAI)，本项目将继续 描述一种独特的DAI新模式。该模型是最近开发的 在这个只有三个动物实验的中心，首先生产 根据生物力学原理建立的物理和数学模型 根据先前的研究确定的。DAI是通过应用非 小型猪口鼻受冲击冲击载荷，从而产生 旋转加速对大脑的影响。初步研究表明， 创伤性轴突损伤是在孤立的情况下产生的，至少有一些 可以通过磁转移非侵入性地检测到这种损伤 成像(MTI)，一种对白质敏感的磁共振技术 改变。31/P或1/H磁测定体内生化变化 磁共振波谱(MRS)显示显著的即刻减少 细胞内的镁是暂时的，是N-乙酰天冬氨酸的 但事实并非如此。如果挫伤是完全不同的 叠加在DAI周围的脑血流(CBF)， 磷酸肌酸(PCr)，以及PCr/PI比值明显降低。我们会 通过用MTI、MRS进一步描述这一模型来扩展这些发现 以及立即具有临床应用的CBF研究。

Because of the importance of traumatic damage to axons and of diffuse axonal injury (DAI) in specific, this project will continue to characterize a unique new model of DAI. The model was recently developed in this Center with only three animal experiments by first producing physical and mathematical models derived from biomechanics principles determined from previous research. DAI is created by applying a non- impact impulsive load to the snout of minipig thereby producing rotational acceleration to the brain. Preliminary studies show that traumatic axonal damage is produced in isolation and that at least some of this damage can be detected non-invasively by magnetic transfer imaging (MTI), a magnetic resonance technique sensitive to white matter changes. In-vivo biochemical changes determined by 31/P or 1/H magnetic resonance spectroscopy (MRS) show marked immediate reduction of intracellular magnesium that was temporary and of n-acetyl-aspartate which was not. These changes were very different if a contusion was superimposed on DAI around which cerebral blood flow (CBF), phosphocreatine (PCr), and the PCr/Pi ratio markedly decreased. We will extend these findings by further characterizing this model with MTI, MRS and CBF studies that have immediate clinical application.