Dry eye is a disorder of the tear film due to tear deficiency or excessivetear evaporation which causes damage to the interpalpebral ocular surfaceand is associated with symptoms of ocular discomfort.The current understanding of the pathogenesis of DES has proceeded fromthe mere recognition of a lack of, or altered quality of tears to recognition ofinflammation as the key pathogenetic mechanism, whether from a systemicautoimmune disease or a local