Shear shock wave propagation in the brain: high frame-rate ultrasound imaging, characterization, and simulations

描述（由申请人提供）：脑损伤的预测指标，如头部损伤标准，依赖于头部运动的外部测量。直接测量大脑运动可以更准确地预测脑损伤。目前估计脑变形的方法不能提供表征与创伤性脑损伤相关的快速瞬态事件所需的高帧率。我们已经开发了新的超声波方法和运动跟踪算法，可以产生高帧率（高达10,000张图像/秒）的电影，以高位移灵敏度（优于1微米）量化大脑运动。我们建议使用这种技术来成像和量化剪切冲击波在离体和在体大脑中的传播。初步数据显示，第一次，剪切冲击波在大脑中的传播。剪切冲击波的剧烈梯度可撕裂和损伤神经元，从而引起弥漫性轴突损伤。我们建议描述大脑的非线性特性，并开发剪切冲击波在大脑中传播的非线性模拟。我们建议将动物实验与组织学分析结合起来，以建立这些快速事件与损伤之间的联系。我们建议将模拟与头部加速度测量相结合，以预测损伤和脑震荡。如果成功，这项研究将改变我们对大脑创伤机制的看法，并将其应用于身体任何部位的创伤。

DESCRIPTION (provided by applicant): Predictors of brain injury, such as the head injury criterion, rely on external measurements of head motion. Direct measurements of brain motion could more accurately predict brain injury. Current methods of estimating brain deformation fail to provide the high frame-rates necessary to characterize the fast transient events asso- ciated with traumatic brain injury. We have developed novel ultrasonic methods and motion tracking algorithms that can generate high frame-rate (up to 10,000 images/second) movies that quantify brain motion with a high displacement sensitivity (better than 1 micron). We propose to use this technique to image and quantify shear shock wave propagation in the ex vivo and in vivo brain. Preliminary data is presented, showing for the first time, shear shock wave propagation in the brain. The violent gradients in shear shock waves may tear and damage neurons thus causing diffuse axonal injuries. We propose to characterize the nonlinear properties of the brain and to develop nonlinear simulations of shear shock wave propagation in the brain. We propose animal experiments in conjunction with histological analysis to establish a link between these rapid events and injury. We propose simulations in conjunction with measurements of head acceleration to predict injuries and concussions. If successful, this research could transform how we view the mechanics of trauma in the brain and be applied to traumatic injuries anywhere in the body.