NeuroTrauma Department, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD 20910, USA.
J Neurosci Methods. 2011 Jan 30;195(1):61-6. doi: 10.1016/j.jneumeth.2010.11.019. Epub 2010 Dec 1.
Exposure to a blast wave generated during an explosion may result in brain damage and related neurological impairments. Several mechanisms by which the primary blast wave can damage the brain have been proposed, including: (1) a direct effect of the shock wave on the brain causing tissue damage by skull flexure and propagation of stress and shear forces; and (2) an indirect transfer of kinetic energy from the blast, through large blood vessels and cerebrospinal fluid (CSF), to the central nervous system. To address a basic question related to the mechanisms of blast brain injury, pressure was measured inside the brains of rats exposed to a low level of blast (~35kPa), while positioned in three different orientations with respect to the primary blast wave; head facing blast, right side exposed to blast and head facing away from blast. Data show different patterns and durations of the pressure traces inside the brain, depending on the rat orientation to blast. Frontal exposures (head facing blast) resulted in pressure traces of higher amplitude and longer duration, suggesting direct transmission and reflection of the pressure inside the brain (dynamic pressure transfer). The pattern of the pressure wave inside the brain in the head facing away from blast exposures assumes contribution of the static pressure, similar to hydrodynamic pressure to the pressure wave inside the brain.
爆炸产生的爆震波会导致脑损伤和相关神经功能障碍。已经提出了几种原发性爆震波损伤大脑的机制，包括：（1）冲击波对大脑的直接作用，通过颅骨弯曲和应力及剪切力的传播导致组织损伤；（2）爆震通过大血管和脑脊液（CSF）将动能间接传递到中枢神经系统。为了解决与爆震性脑损伤机制相关的一个基本问题，对暴露于低水平爆震（约 35kPa）的大鼠大脑内的压力进行了测量，同时大鼠相对于原发性爆震波处于三种不同的位置；头部朝向爆震源、右侧暴露于爆震源和头部背向爆震源。数据显示，根据大鼠相对于爆震源的方向，大脑内的压力迹线呈现不同的模式和持续时间。正面暴露（头部朝向爆震源）导致压力迹线的幅度更高、持续时间更长，这表明压力在大脑内的直接传递和反射（动态压力传递）。在头部背向爆震源暴露的情况下，大脑内的压力波模式假设静压力的贡献类似于对大脑内压力波的动压力。
