Vitreous humor viscosity effect on temperature distribution within a human eye model

Abstract

The eye is a complex organ that responds to light by processing its signal and sending it to the brain and producing images. Therefore, the human eye is a major organ of the human body. A lens is a significant component of the human eye and also plays a central role in vision. The normal temperature of the eye lens should be below 38.5°C. The homogeneous gel in the eye is the vitreous humor. Due to aging, it gradually becomes a liquefied vitreous humor. This causes a phenomenon called eye-floaters. The vitreous humor viscosity effects caused by temperature increases of the lens and maybe a very important influence the thermal physiological responses, which can be the cause of deterioration of the lens. However, the results of vitreous humor viscosity effects due to aging are not well understood. Thus, investigation to obtain knowledge and guidelines to avoid the vitreous humor viscosity effects will help prevent damage to the eyes. This study presents a numerical analysis of temperature distribution and thermal physiologic response within a heterogeneous model of the human eye. A three-dimensional (3D) human eye model and finite element method (FEM) are used. The heat transfer equation in a porous media and the Navier-Stroke equation characterizes the thermal behavior and blood (fluid) flow in a 3D human eye model. The effects of vitreous humor viscosity are investigated. These obtained results from this study provide guidelines that can indicate limitations regarding temperature increase in the human eye during exposure to thermal effects.