Dry eye disease (DED) is known to be among the most frequently occuring ocular morbidities. It is a growing public health concern affecting 25% of patients who visit ophthalmic clinics.For many years, DED was considered to be limited to dryness of the eyes due to decrease in the aqueous phase in the tear film. In 2007, the International Dry Eye Workshop discussed the definition and classification of DED and developed a new vision for the definition and the three-part classification of DED on the basis of etiology, mechanism, and severity of DED. Moreover, DED can be episodic or chronic. Episodic DED occurs when environmental or visual tasks with reduced blinking overwhelm the stability of the tear and produce symptomatic DED. Chronic DED, although aggravated by the same environmental conditions, persists continuously with symptoms and possible damage to the ocular surface. Because the tear film in DED patients is not stable and incapable to maintain the protective qualities that are important for its structure and function, patients usually experience the discomfort manifestations associated with DED such as burning, stinging, foreign body sensation, ocular fatigue, grittiness, tearing, and dryness. Patients may complain of symptoms of DED in the presence or absence of the known signs and DED may be diagnosed based only on the signs observed by a healthcare professional in the absence of symptoms reported by the patients.Since the initial description, the therapeutic efficacy of CsA for human KCS has been well documented, with evidence ranging from several small single center randomized double-masked clinical trials to several large multicenter randomized, double-masked clinical trials.Therefore, the aim of the work is to evaluate the effect of using topical CsA in treatment of moderate to severe dry eye.
Since the initial description, the therapeutic efficacy of CsA for human KCS has been well documented, with evidence ranging from several small single center randomized double-masked clinical trials to several large multicenter randomized, double-masked clinical trials.(10-12) Therefore, the aim of the work is to evaluate the effect of using topical CsA in treatment of moderate to severe dry eye.