A mesh-free approach to cornea-aqueous humor interaction during tonometry tests

Andrea Montanino, Maurizio Angelillo, Anna Pandolfi

Abstract


The dynamic tonometer test (air-puff test) is an in-vivo investigative procedure routinely utilized in ophthalmology to estimate the intraocular pressure (IOP). A rapid, localized air jet applied on the anterior surface induces the inward motion of the cornea, which interacts with the aqueous humor — filling the narrow space between cornea and iris — and has a strong influence on corneal dynamics. Potentially, this quick and painless test could be combined with inverse analysis methods to characterize the patient-specific mechanical properties of the human cornea. As a step towards this aim, the present study describes a fluid-structure interaction (FSI) approach based on a simplified geometry to simulate the anterior chamber of the eye undergoing the air-puff test. We regard the cornea as a non-linear, elastic, and isotropic membrane described through an analytical model, discretizing the weakly compressible Newtonian fluid with a mesh-free particle approach. Numerical analyses reveal a marked influence of the fluid on corneal dynamics. Additionally, we investigate the possibility of using the test dynamics to estimate IOP.


Keywords


air-puff test; collocation methods; fluid-dynamics, fluid-solid interaction; mesh-free methods; particle methods

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References


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