DRY EYE SYNDROME or keratoconjunctivitis sicca is a disease of the ocular surface attributable to different disturbances of the natural function and protective mechanism of the external eye leading to an unstable tear film. This disease is associated with a broad spectrum of ocular symptoms ranging from mild transient to persistent irritation such as burning, itching, redness, pain, ocular fatigue, and visual disturbances.
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