# Numerical Simulation on Corneal Surface Behavior Applying Luminous Beam Levels
## 1 Introduction  
In Mexico, visual disease cases number around 7.1 million, and based on a study by Instituto Nacional de Estadistica y Geografia (INEGI), 33% have visual impairment or blindness. These diseases affect people who are 50 years old to elderly and are often due to long periods of luminescence exposure from high-level irradiation sources toward the ocular organs [1; 2; 3]. The first model of the eye that used the Finite Element Method (FEM) was from around 1997. This model was made based on empirical values according to the anatomy of the human eye. The prediction of optical image quality at various levels of defocus aided this study with refractive surgical methods, such as photorefractive keratectomy and automated lamellar keratoplasty [4]. In 2002, in Germany, experiments in two locations with different values of UV and UVB radiation (305 nm and 315 nm) demonstrated that several instances of damage appeared in areas with higher ambient radiation [5]. In 2006 in Singapore, a 2D finite element-based model was designed as a thermal model for early detection of disease, and research revealed the effectiveness against the infrared method (0.33% error) and the FEM model (0.127 error) [6]. In 2010, a mathematical model was performed applying a variant of the FEM (sigma) to increase the accuracy of bioheat transfer due to experimental treatments by the method of immunotherapy against cancerous tumors in the eye. By using the hyperthermia method, the tumor temperature can be raised without affecting its properties [7]. In 2012, an implant was developed to treat glaucoma; the cornea model(located for transplantation) was used under specific conditions, and the simulation was performed based on the temperature variant and its prevention in the implant [8]. In 2015, Salesian Polytechnic University developed an ocular model of the human eye as a tool for intraocular pressure measurement for patients requiring glaucoma prevention. The cornea thickness was used to obtain a mathematical model to determine the severity of the disease in patients [9]. Similarly, in 2015, a model of the human organ was announced; this one was performed to study primary eye blast injury, calculating the stresses around it. Considering the eye's shape, it is possible to produce a resonance effect, increasing the damage, considering the loading conditions in different lengths from the blast and the explosive mass loading (trinitrotoluene) [10]. A numerical simulation by [PERSON] and [PERSON] aims to analyze the mechanical properties in the cornea post-surgery. It is used for visual correction in patients with eye diseases. The numerical models provide quantitative and accurate information about the refractive properties in the cornea [11]. In 2016, a FEM model of the human eye was generated, allowing daily evaluation of the optic nerve motion [12]. In Iran in 2016, a numerical analysis of the whole eyeball (cornea, aqueous humor, iris, ciliary body, crystalline lens, vitreous humor, retina, sclera, optic nerve, and external eye muscles) under loads that are created by trinitrotoluene was performed. This analysis was performed through a Lagrangian model and a Eulerian computational method [13]. In 2016, an analysis of the damage caused by a tennis ball at 69 m/s hitting a human eye (ex vivo) was performed. The study defines the stresses and deformations in the main parts of the eyeball, which, including the cornea, by magnetic resonance imaging results exhibit displacements of up to 0.045 m and stress of 8.27 MPa [14]. In the same year, by [PERSON], [PERSON] et al., an in vivo cycle method in a porcine eye was developed to determine the variation of the mechanical behavior of the ocular surface (sclera). The methodology proposes an analysis of the sclera, measuring the internal displacements generated through digital cameras and image correlation software [15]. Computational models were made using topographic data of 10 patients who suffered refractive grid extraction due to astigmatism or myopia.