Mechanical characterization of the human pia-arachnoid complex
Mechanical characterization of the human pia-arachnoid complex
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DOI：
10.1016/j.jmbbm.2021.104579
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发表时间：
2021-05-18
影响因子：
3.9
通讯作者：
Coats, Brittany
中科院分区：
文献类型：
--
作者：
Benko, Nikolaus;Luke, Emma;Coats, Brittany
创伤性脑损伤（TBI）是全球健康中的一个重大问题，影响着各种各样的患者。轻度 TBI，通常称为脑震荡，是直接或间接撞击导致头部快速加速的结果。撞击产生的动能转化为大脑变形，导致细胞破裂。这种能量转移部分是由软脑膜-蛛网膜复合体（PAC）介导的，PAC是一层解剖结构，形成大脑和头骨之间的物理连接。一段时间以来，人们已经了解正确量化 PAC 力学用于 TBI 计算模型的重要性，但尚未获得来自人类受试者的数据。在这项研究中，我们使用静压流体加压结合光学相干断层扫描来量化五名死后人类受试者的 PAC 正常牵引模量。在每个大脑的多个位置进行的测试表明，脑颅骨硬度分布不均匀。材料对牵引载荷的响应是线性的，平均正常牵引模量为 12.6 +/- 4.8 kPa。大脑上部区域的模量比下部区域高 21%。与区域微观结构数据的比较表明蛛网膜小梁的体积分数和模量之间存在潜在关系。与同时测量的微观结构特性的比较显示，蛛网膜厚度与正常牵引模量之间呈正相关。这项研究首次表征了人类软脑膜-蛛网膜复合体的力学特征并现场量化了材料特性。这些发现表明，在 TBI 计算模型中实施脑-颅骨界面的异质模型可能会导致更现实的损伤预测。
Traumatic brain injury (TBI) is a significant problem in global health that affects a wide variety of patients. Mild forms of TBI, commonly referred to as concussion, are a result of rapid accelerations of the head from either direct or indirect impacts. Kinetic energy from the impact is transferred into deformation of the brain, leading to cellular disruption. This transfer of energy is in part mediated by the pia-arachnoid complex (PAC), a layer of anatomical structures that forms the physical connection between the brain and the skull. The importance of properly quantifying the mechanics of the PAC for use in computational models of TBI has been understood for some time, but data from human subjects has been unavailable. In this study, we quantify the normal traction modulus of the PAC in five post-mortem human subjects using hydrostatic fluid pressurization in combination with optical coherence tomography. Testing at multiple locations across each brain reveals that brain-skull stiffness is heterogeneously distributed. The material response to traction loading was linear, with a mean normal traction modulus of 12.6 +/- 4.8 kPa. Modulus was 21% greater in superior regions of the brain compared to inferior regions. Comparisons with regional microstructural data suggests a potential relationship between the volume fraction of arachnoid trabeculae and modulus. Comparisons to coincident measurements of microstructural properties showed a positive correlation between arachnoid membrane thickness and normal traction modulus. This study is the first to characterize the mechanics of the human pia-arachnoid complex and quantify material properties in situ. These findings suggest implementing a heterogeneous model of the brain-skull interface in computational models of TBI may lead to more realistic injury prediction.