title: A poroelastic model for the perfusion of the lamina cribrosa in the optic nerve head.
abstract: In this work we present a mathematical model for the coupling between biomechanics and hemodynamics in the lamina cribrosa, a thin porous tissue at the base of the optic nerve head which is thought to be the site of injury in ocular neurodegenerative diseases such as glaucoma. In this exploratory two-dimensional investigation, the lamina cribrosa is modeled as a poroelastic material where blood vessels are viewed as pores in a solid elastic matrix. The model is used to investigate the influence on the distributions of stress, blood volume fraction (or vascular porosity) and blood velocity within the lamina cribrosa due to the application of different levels of the intraocular pressure (IOP) and the enforcement of different mechanical constraints at the lamina's boundary. The model simulations suggest that the degree of fixity of the boundary constraint strongly influences the lamina's response to IOP elevation. Specifically, when the boundary is mechanically clamped, IOP elevation leads to an increase in stress close to the lamina's boundary, making it more susceptible to tissue damage. On the other hand, when rotations are allowed at the boundary, the most vulnerable region appears to be located at the lamina's central axis, in proximity of the eye globe, where increased stress and reduced vascular porosity and blood velocity are predicted for increased levels of IOP.
authors.affiliation: Dipartimento di Matematica "F. Enriques", Università degli Studi di Milano, via Saldini 50, 20133 Milano, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Causin
authors.affiliation: Department of Mathematical Sciences, Indiana University Purdue University, Indianapolis, 402 N. Blackford St., LD270 Indianapolis, IN, USA; Eugene and Marilyn Glick Eye Institute, Indiana University, 1160 W. Michigan St., LD270 Indianapolis, IN, USA; Institut de recherche en mathématiques, interactions et applications, 7 rue René Descartes, F-67084 Strasbourg Cedex, France.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Guidoboni
authors.affiliation: Eugene and Marilyn Glick Eye Institute, Indiana University, 1160 W. Michigan St., LD270 Indianapolis, IN, USA.
authors.forename: Alon
authors.initials: A
authors.lastname: Harris
authors.affiliation: Department of Mathematical Sciences, Indiana University Purdue University, Indianapolis, 402 N. Blackford St., LD270 Indianapolis, IN, USA.
authors.forename: Daniele
authors.initials: D
authors.lastname: Prada
authors.affiliation: Dipartimento di Matematica "F. Brioschi", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Sacco
authors.affiliation: Degreed in Mathematical Engineering, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: Samuele
authors.initials: S
authors.lastname: Terragni
mesh_terms: D006801:Humans; D008954:Models, Biological; D009900:Optic Nerve / Q000502:physiology*; D012590:Sclera / Q000098:blood supply*
keywords: Biological tissues; Eye; Finite element method; Lamina cribrosa; Optic nerve head; Poroelastic models