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Abstract #61559 Published in IGR 17-1
A porohyperelastic finite element model of the eye: the influence of stiffness and permeability on intraocular pressure and optic nerve head biomechanics
Ayyalasomayajula A; Park RI; Simon BR; Vande Geest JPComputer Methods in Biomechanics and Biomedical Engineering 2015; 0: 1-12
Progressively deteriorating visual field is a characteristic feature of primary open-angle glaucoma (POAG), and the biomechanics of optic nerve head (ONH) is believed to be important in its onset. We used porohyperelasticity to model the complex porous behavior of ocular tissues to better understand the effect variations in ocular material properties can have on ONH biomechanics. An axisymmetric model of the human eye was constructed to parametrically study how changes in the permeabilities of retina-Bruch's-choroid complex [Formula: see text], sclera [Formula: see text], uveoscleral pathway [Formula: see text], and trabecular meshwork [Formula: see text] as well as how changes in the stiffness of the lamina cribrosa (LC) and sclera affect IOP, LC strains, and translaminar interstitial pressure gradients (TLIPG). Decreasing [Formula: see text] from 5 × 10(- 12) to 5 × 10(- 13) m/s increased IOP and LC strains by 17%, and TLIPG by 21%. LC strains increased by 13% and 9% when the scleral and LC moduli were decreased by 48% and 50%, respectively. In addition to the trabecular meshwork and uveoscleral pathway, the retina-Bruch's-choroid complex had an important effect on IOP, LC strains, and TLIPG. Changes in [Formula: see text] and scleral modulus resulted in nonlinear changes in the IOP, and LC strains especially at the lowest [Formula: see text] and [Formula: see text]. This study demonstrates that porohyperelastic modeling provides a novel method for computationally studying the biomechanical environment of the ONH. Porohyperelastic simulations of ocular tissues may help provide further insight into the complex biomechanical environment of posterior ocular tissues in POAG.
a Department of Aerospace and Mechanical Engineering , University of Arizona , Tucson , AZ 85721 , USA.
Full articleClassification:
6.1.3 Factors affecting IOP (Part of: 6 Clinical examination methods > 6.1 Intraocular pressure measurement; factors affecting IOP)
15 Miscellaneous