Eye Injury In Tennis

The sclera is a dense-fibrous connective tissue extends from the cornea to the optic nerve. The sclera is primarily consisted of avascular lamellae of collagen fibers which is responsible of bearing the Intraocular Pressure (IOP) [1]. Collagen type I is the core components of the sclera and they have to provide the eye with compulsory mechanical strength to be able to bear the IOP as well [2]. Each year above 1.9 million people experience one type of eye injuries in the United States alone [3]. Trauma is one of the most usual ones which as a result of that nearly 30,000 people lost their vision in the United States [4]. The causes of these injuries have mostly been reported for the vehicle-related eye injuries with 66,000 people [3].

In addition, as the injuries related to civilian and military sectors have been a growing area of increasing, it is worth investigating that how the process of injury is and how it can affect the eye components after injury [6]. Sports injuries, including tennis injuries, can also bring about a trauma injury to the eye [7, 8]. Although the injuries occur in tennis are similar to other sports [9], the injuries that occur in the tennis do have an unique profile since the ball in this game can hit the eye at a very high velocity (155 mph serve which is the highest speed of the tennis ball in the Davis Cup match, 2004 [10]), sort, and amount of spin [11] which may invoke a serious type of injury to the eye components once has a collision with that. Experimental investigations of the process of injury to the human eye due to car crash, military issues, IOP increasing, tennis ball impact, etc, are neither plausible nor practical, and this is why there is a need to employ computational models. Stitzel et al. [12] made

Uchio et al. [22] in 1999 measured the mechanical properties of the sclera via a uniaxial tensile test machine to be incorporated in a computational Finite Element (FE) model. While Nash et al. [23] calculated the mechanical behavior of the scleral tissue under axial loading, the compressive mechanical properties of the sclera were measured by Barraglioli et al. [24]. So far there is no strong agreement as whether the sclera tissue is isotropic [25] or anisotropic [26]. Some other studies also performed a comparative study to validate the rate and the directional dependence of the sclera to figure out whether the sclera is both anisotropic and viscoelastic or not [22, 27]. Some studies by considering the anisotropic nonlinear mechanical behavior of the scleral tissue, proposed an anisotropic hyperelastic constitutive model for the posterior sclera [19]. In addition, the anisotropic responses of porcine sclera in the presence of shear stress were quantified through a new strain measurement technique, namely, ultrasound speckle tracking [28]. Downs et al. [29] in this case characterized the linear viscoelastic material properties of peripapillary sclera in both the rabbit and monkey eyes using a coupled spectral reduced relaxation function. The