Tears serve a variety of functions, which accounts for the kinds of complications their deficiency can cause. They lubricate the eye, supply it with nutrients and oxygen, and help to focus images and clear the eye of debris.
Untreated, severe dry eye disease can result in scarring, ulceration, infection and even perforation of the cornea, the clear outer layer of the eye that protects the iris, pupil and anterior chamber and accounts for much of the eyes optical power.
But the current and evolving knowledge of the nature of tears and their production has led to a better understanding of the various causes of dry eye disease and major improvements in treating this all-too-common condition.
We used to think that tears were like salty water just add more liquid and youll be fine, Dr. Bishop explained. We now know that there are many hundreds of substances in tears, including 1,500 proteins, and three main components. We try to pinpoint why a particular person is experiencing dry eye and treat that persons specific problem.
Tears are now known to have layers: an outer fatty ...