Modern trends in tear replacement therapy for patients with dry eye syndrome

Abstract

Today, the dry eye syndrome therapy is based on the techniques aimed at compensating for loss of moisture in the conjunctival cavity (the so-called tear replacement therapy) either by additional moistening of the eye surface, or by maintaining the moisture in the conjunctival cavity. Traditionally, the first step is to moisturise the eye surface, and the artificial tear products is the leader in this area. In recent years, natural mucopolysaccharides are one of the basic components of artificial tears that attract the greatest practical interest, and among them is the hyaluronic acid, or rather its sodium salt, which is almost identical in pharmacological properties to native hyaluronic acid with the respective molecular weight. Hyaluronic acid is characterized by high mucoadhesiveness, which allows the artificial tear solution based on this polymer to bind to mucins on the eye surface and prolong the residence time of the formulation on the ocular surface. The even more significant property of high molecular-weight HyA is the so-called thixotropy: the high molecular-weight HyA has a high viscosity on the open eye, which provides good wettability of the ocular surface. Today, preservative-free solutions based on the hyaluronic acid sodium salt, which are characterized by high thixotropy, hygroscopicity, mucoadhesiveness and good tolerability, are the priority. The high effectiveness of such drugs has been established. They provide deep hydration in the treatment of dry eye syndrome due to Sjögren's syndrome, meibomian blepharitis and perimenopause, as well as dry eye syndrome in children. The latter was developed due to neuroparalytic keratitis, chronic blepharitis, and systematic damage to the ocular surface by eye drops containing preservatives.