Effects of collagen microstructure and material properties on the deformation of the neural tissues of the lamina cribrosa.
Effects of collagen microstructure and material properties on the deformation of the neural tissues of the lamina cribrosa.
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DOI：
10.1016/j.actbio.2017.05.042
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发表时间：
2017-08
影响因子：
9.7
通讯作者：
Sigal IA
中科院分区：
文献类型：
--
作者：
Voorhees AP;Jan NJ;Sigal IA
人们普遍认为眼压（IOP）引起的神经组织孔内变形是导致神经退行性变和青光眼的原因之一。我们的目的是研究LC的微观结构和力学性能如何决定LC孔内神经组织的力学损伤。采用偏振光显微镜对3只羊视神经头（ONH）在中尺度（4.4µm）和微尺度（0.73µm）分辨率下的组织学切片进行胶原密度和取向测定。中尺度纤维感知有限元模型首先用于计算眼压为30 mmHg时ONH的变形。然后将结果用作LC区域微尺度模型的边界条件。模型预测LC神经组织受到较大损伤，第95百分位第一主应变在7-12%之间。靠近巩膜边界的毛孔比靠近中心区域的毛孔有更大的拉伸（10.0±1.4% vs. 7.2±0.4%;p=0.014; mean±SD）。材料特性的变化改变了神经组织损伤的最小、中值和最大水平，但在很大程度上没有改变孔间变化的模式，这表明这些模式是由LC梁和孔的底层结构和几何形状决定的。据我们所知，这是第一个重现实验观察到的高度异质神经组织应变场的计算模型。
It is widely considered that intraocular pressure (IOP)-induced deformation within the neural tissue pores of the lamina cribrosa (LC) contributes to neurodegeneration and glaucoma. Our goal was to study how the LC microstructure and mechanical properties determine the mechanical insult to the neural tissues within the pores of the LC. Polarized light microscopy was used to measure the collagen density and orientation in histology sections of three sheep optic nerve heads (ONH) at both mesoscale (4.4 µm) and microscale (0.73 µm) resolutions. Mesoscale fiber-aware FE models were first used to calculate ONH deformations at an IOP of 30 mmHg. The results were then used as boundary conditions for microscale models of LC regions. Models predicted large insult to the LC neural tissues, with 95th percentile 1st principal strains ranging from 7–12%. Pores near the scleral boundary suffered significantly higher stretch compared to pores in more central regions (10.0 ± 1.4% vs. 7.2 ± 0.4%; p=0.014; mean ± SD). Variations in material properties altered the minimum, median, and maximum levels of neural tissue insult but largely did not alter the patterns of pore-to-pore variation, suggesting these patterns are determined by the underlying structure and geometry of the LC beams and pores. To the best of our knowledge, this is the first computational model that reproduces the highly heterogeneous neural tissue strain fields observed experimentally.
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DOI：
10.1115/1.3113682
发表时间：
2009-05
期刊：
Journal of biomechanical engineering
影响因子：
--
作者：
Girard MJ;Downs JC;Burgoyne CF;Suh JK
通讯作者：
Suh JK
影响因子：
3.7
作者：
Exler, Rachel E.;Guo, Xiaoxin;Sivak, Jeremy M.
通讯作者：
Sivak, Jeremy M.
DOI：
10.1080/10255842.2015.1052417
发表时间：
2016
影响因子：
1.6
作者：
Ayyalasomayajula A;Park RI;Simon BR;Vande Geest JP
通讯作者：
Vande Geest JP
影响因子：
3.4
作者：
Burgoyne, Claude F.
通讯作者：
Burgoyne, Claude F.
影响因子：
4.4
作者：
Fazio, Massimo A.;Grytz, Rafael;Downs, J. Crawford
通讯作者：
Downs, J. Crawford