Guidelines for the treatment of chronic dry eye disease.

Keratoconjunctivitis sicca (KCS), also known as dry eye syndrome, dry eye disease, chronic dry eye disease, or keratitis sicca, refers to disorders of the tear film caused by reduced tear production, poor tear quality, or excessive tear evaporation. These disorders are associated with such symptoms of ocular discomfort as irritation, foreign body sensation, or redness, and may cause disease of the ocular surface.