Posters

Assessment of the intraocular pressure (IOP) on the cornea and lens radius of curvatures: a numerical finite element modeling

Poster Details

First Author: A.Shojaei Baghini IRAN

Co Author(s):    A. Karimi   R. Razaghi   M. Navidbakhsh   H. Mohammad Rabie           

Abstract Details

Purpose:

Increasing the pressure in the eye would lead to bulge of the cornea and, consequently, distortion of the corneal surface that causes blurred vision. In this study a three-dimensional computational Fluid-Structure Interaction (FSI) model was established to analyze the biomechanical factors contributing to the distorted shape of the cornea and lens. Furthermore, the deformations as well as the stresses induced on the lens have also been measured.

Setting:

To do this, the radius of curvature of the cornea and lens was measured at three different intraocular pressure (IOP). The tissue deformations and stresses maps predicted by the models for the IOP of 10, 20, and 30 mmHg.

Methods:

The analyses revealed that three factors affect the shape distortion of the corneas: (i) localized thinning at its apex, and (ii) reduction or minimization of the tissues meridian elastic modulus as well as (iii) increasing the maximum von Mises stress perpendicular to the corneal surface.

Results:

The highest radius of curvature was seen in the IOP of 30 mmHg, while the lowest one was in 10 mmHg. In contrast, the highest radius of curvature for the lens was seen to be located in the IOP of 10 mmHg, whereas the lowest one was observed in the IOP of 30 mmHg. The numerical results also depicted the highest von Mises stresses in the IOP of 30 mmHg with 244.90 kPa, while the lowest one was observed in the cornea with 10 mmHg (28.89 kPa). The von Mises stress on the lens was showed the same pattern as the stress of 9.14 and 19.38 kPa were seen in the IOP of 10 and 30 mmHg, respectively.

Conclusions:

Maximal stress levels occurred at the centers of the bulged regions, at the thinnest points. The IOP levels showed a little influence on the dioptric power of the healthy cornea, however, a substantial influence in keratoconic conditions would be expected. Theese results might allowed characterization of the biomechanical interactions in keratoconus, toward understanding the aetiology of this poorly studied malady.

Financial Disclosure:

NONE