Lamina Cribrosa Pore Shape and Size as Predictors of Neural Tissue Mechanical Insult
| Autor: | John G. Flanagan, Ian A. Sigal, Morgan E. Austin, Ning-Jiun Jan, Richard A. Bilonick, Andrew P. Voorhees, Jeremy M Sivak |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Lamina Materials science microstructure Finite Element Analysis Optic Disk Optic disk Stress Ophthalmology & Optometry Medical and Health Sciences biomechanics Perimeter 03 medical and health sciences Linear regression Ultimate tensile strength Animals Computer Simulation Composite material Anisotropy Intraocular Pressure Sheep convexity Glaucoma optic nerve head finite element modeling Optic Nerve Anatomy Biological Sciences Microstructure Mechanical 030104 developmental biology glaucoma Cylinder stress Stress Mechanical lamina cribrosa |
| Zdroj: | Investigative Ophthalmology & Visual Science Investigative ophthalmology & visual science, vol 58, iss 12 |
| ISSN: | 1552-5783 0146-0404 |
| Popis: | Author(s): Voorhees, Andrew P; Jan, Ning-Jiun; Austin, Morgan E; Flanagan, John G; Sivak, Jeremy M; Bilonick, Richard A; Sigal, Ian A | Abstract: PurposeThe purpose of this study was to determine how the architecture of the lamina cribrosa (LC) microstructure, including the shape and size of the lamina pores, influences the IOP-induced deformation of the neural tissues within the LC pores using computational modeling.MethodsWe built seven specimen-specific finite element models of LC microstructure with distinct nonlinear anisotropic properties for LC beams and neural tissues based on histological sections from three sheep eyes. Changes in shape (aspect ratio and convexity) and size (area and perimeter length) due to IOP-induced hoop stress were calculated for 128 LC pores. Multivariate linear regression was used to determine if pore shape and size were correlated with the strain in the pores. We also compared the microstructure models to a homogenized model built following previous approaches.ResultsThe LC microstructure resulted in focal tensile, compressive, and shear strains in the neural tissues of the LC that were not predicted by homogenized models. IOP-induced hoop stress caused pores to become larger and more convex; however, pore aspect ratio did not change consistently. Peak tensile strains within the pores were well predicted by a linear regression model considering the initial convexity (negative correlation, P l 0.001), aspect ratio (positive correlation, P l 0.01), and area (negative correlation, P l 0.01). Significant correlations were also found when considering the deformed shape and size of the LC pores.ConclusionsThe deformation of the LC neural tissues was largely dependent on the collagenous LC beams. Simple measures of LC pore shape and area provided good estimates of neural tissue biomechanical insult. |
| Databáze: | OpenAIRE |
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