Contact lens-induced dry eye is different than normal dry eye because contact lenses affect the dynamics of the ocular environment, says Arthur B. Epstein, O.D., F.A.A.O. You have to differentiate pseudo dry eye from real dry eye and marginal dry eye.

Marginal dry eye basically means you have a patient who�s normal. You put a contact lens in, suddenly, he has dry eye symptoms.

Pseudo dry eye is more typical with conventional lenses, not frequently replaced lenses. With pseudo dry eye, the eye isn�t getting enough oxygen. As the cornea becomes increasingly hypoxic, the lens becomes less hydrated and less permeable. They patients don�t really have dry eye, they have marginal physiology. They need high-Dk lenses.