Regional mechanical properties of human brain tissue for computational models of traumatic brain injury
Regional mechanical properties of human brain tissue for computational models of traumatic brain injury
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DOI：
10.1016/j.actbio.2017.03.037
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发表时间：
2017-06-01
影响因子：
9.7
通讯作者：
Morrison, Barclay, III
中科院分区：
文献类型：
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作者：
Finan, John D.;Sundaresh, Sowmya N.;Morrison, Barclay, III
为了确定粘弹性剪切模量，应力松弛压痕测试进行癫痫手术过程中切除的人脑组织的样品。通过使用直径为500 mm的压头，测量皮质灰色和白色物质以及海马子区域的局部机械性能。所有区域均为高度粘弹性。皮质灰质比白色物质或海马体更具有顺应性，两者在模量上相似。虽然剪切模量与供体的年龄无关，但男性供体的皮质比女性供体的皮质明显更硬。所提出的材料特性将有助于填充大脑的有限元模型，因为它们变得更加解剖学detailed.Statement的显著性我们提出了第一个机械表征新鲜的，术后人脑组织使用压痕加载模式。压痕产生高度局部化的数据，允许从手术期间切除的小组织样本中确定结构特定的机械性能。它还避免了尸体组织的缺陷，并允许在退行性过程改变机械性能之前收集数据。为了正确预测创伤性脑损伤，有限元模型必须计算头部撞击时颅内变形。损伤的功能后果取决于受损的解剖结构。因此，发病率取决于变形在结构上的分布。准确预测结构特定的变形需要结构特定的力学性能。这些数据将有助于更深入地了解导致创伤性脑损伤的物理机制。(C)2017 Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
To determine viscoelastic shear moduli, stress relaxation indentation tests were performed on samples of human brain tissue resected in the course of epilepsy surgery. Through the use of a 500 mm diameter indenter, regional mechanical properties were measured in cortical grey and white matter and subregions of the hippocampus. All regions were highly viscoelastic. Cortical grey matter was significantly more compliant than the white matter or hippocampus which were similar in modulus. Although shear modulus was not correlated with the age of the donor, cortex from male donors was significantly stiffer than from female donors. The presented material properties will help to populate finite element models of the brain as they become more anatomically detailed.Statement of SignificanceWe present the first mechanical characterization of fresh, post-operative human brain tissue using an indentation loading mode. Indentation generates highly localized data, allowing structure-specific mechanical properties to be determined from small tissue samples resected during surgery. It also avoids pitfalls of cadaveric tissue and allows data to be collected before degenerative processes alter mechanical properties. To correctly predict traumatic brain injury, finite element models must calculate intracranial deformation during head impact. The functional consequences of injury depend on the anatomical structures injured. Therefore, morbidity depends on the distribution of deformation across structures. Accurate prediction of structure-specific deformation requires structure-specific mechanical properties. This data will facilitate deeper understanding of the physical mechanisms that lead to traumatic brain injury. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.