#### Presentation Title

Mathematical Model to Noninvasively Detect Dry-Eye Diseases

#### Start Date

November 2016

#### End Date

November 2016

#### Location

HUB 302-165

#### Type of Presentation

Poster

#### Abstract

Wavelength-dependent interferometry is a non-invasive technique that can accurately diagnose patients with dry eye diseases. The method requires shining a light onto the surface of the eye while measuring the reflectance. Since there are several layers of the tear film laying on the cornea, light must be emitted at multiple wavelengths to produce sufficient degrees of freedom to determine the thicknesses. Based on the resulting reflectance the thicknesses of the tear film layers can be extracted implicitly from the reflectance. In this work, a mathematical model that describes the reflectance of the eye is derived. The model takes into account electromagnetic properties of how light is transmitted and reflected through different media. Numerical implementation of the interferometry technique is quite complicated. In a 2013 patent, the calculation of the reflectance alone takes over ten pages of code and a spectrum could take up to 45 minutes to generate. Our future work is to speed up the curving fitting process so that diagnoses in the optometry office will not take so long. It has also been found that the current model may fit well in some cases while not for other sets of data. It was believed that the model is lacking the inclusion of the scalar light scattering theory; thus our future work will also include refining the inclusion of this essential theory into the mathematical model.

Mathematical Model to Noninvasively Detect Dry-Eye Diseases

HUB 302-165

Wavelength-dependent interferometry is a non-invasive technique that can accurately diagnose patients with dry eye diseases. The method requires shining a light onto the surface of the eye while measuring the reflectance. Since there are several layers of the tear film laying on the cornea, light must be emitted at multiple wavelengths to produce sufficient degrees of freedom to determine the thicknesses. Based on the resulting reflectance the thicknesses of the tear film layers can be extracted implicitly from the reflectance. In this work, a mathematical model that describes the reflectance of the eye is derived. The model takes into account electromagnetic properties of how light is transmitted and reflected through different media. Numerical implementation of the interferometry technique is quite complicated. In a 2013 patent, the calculation of the reflectance alone takes over ten pages of code and a spectrum could take up to 45 minutes to generate. Our future work is to speed up the curving fitting process so that diagnoses in the optometry office will not take so long. It has also been found that the current model may fit well in some cases while not for other sets of data. It was believed that the model is lacking the inclusion of the scalar light scattering theory; thus our future work will also include refining the inclusion of this essential theory into the mathematical model.