Imperial College London
Alternate

Professor C. Ross Ethier

Faculty of Engineering, Department of Bioengineering

Visiting Professor
 
 
 
//

Contact

 

r.ethier

 
 
//

Location

 

Royal School of MinesSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Safa:2021:10.1101/2021.04.16.440170,
author = {Safa, BN and Read, AT and Ethier, CR},
doi = {10.1101/2021.04.16.440170},
title = {Assessment of the Viscoelastic Mechanical Properties of the Porcine Optic Nerve Head using Micromechanical Testing and Finite Element Modeling},
url = {http://dx.doi.org/10.1101/2021.04.16.440170},
year = {2021}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - <jats:title>Abstract</jats:title><jats:p>Optic nerve head (ONH) biomechanics is centrally involved in the pathogenesis of glaucoma, a blinding ocular condition often characterized by elevation and fluctuation of the intraocular pressure and resulting loads on the ONH. Further, tissue viscoelasticity is expected to strongly influence the mechanical response of the ONH to mechanical loading, yet the viscoelastic mechanical properties of the ONH remain unknown. To determine these properties, we conducted micromechanical testing on porcine ONH tissue samples, coupled with finite element modeling based on a mixture model consisting of a biphasic material with a viscoelastic solid matrix. Our results provide a detailed description of the viscoelastic properties of the porcine ONH at each of its four anatomical quadrants (i.e., nasal, superior, temporal, and inferior). We showed that the ONH’s viscoelastic mechanical response can be explained by a dual mechanism of fluid flow and solid matrix viscoelasticity, as is common in other soft tissues. We obtained porcine ONH properties as follows: matrix Young’s modulus <jats:italic>E</jats:italic>=1.895 [1.056,2 .391] kPa (median [min., max.]), Poisson’s ratio <jats:italic>ν</jats:italic>=0.142 [0.060,0 .312], kinetic time-constant <jats:italic>τ</jats:italic>=214 [89,921] sec, and hydraulic permeability <jats:italic>k</jats:italic>=3.854 × 10<jats:sup>−1</jats:sup> [3.457 × 10<jats:sup>−2</jats:sup>,9.994 × 10<jats:sup>−1</jats:sup>] mm<jats:sup>4</jats:sup>/(N sec). These values can be used to design and fabricate physiologically appropriate <jats:italic>ex vivo</jats:italic> test environments (e.g., 3D cell culture) to further understand glaucoma pathophysiology.</jats:p>
AU  - Safa,BN
AU  - Read,AT
AU  - Ethier,CR
DO  - 10.1101/2021.04.16.440170
PY  - 2021///
TI  - Assessment of the Viscoelastic Mechanical Properties of the Porcine Optic Nerve Head using Micromechanical Testing and Finite Element Modeling
UR  - http://dx.doi.org/10.1101/2021.04.16.440170
ER  -
Download