Dry Eye is a chronic disease, estimated to affect nearly 22 million Americans. Dry Eye occurs when eyes do not produce the necessary quantity or quality of tears. One of the most critical components to having healthy, comfortable eyes and good vision is the tear film.
The tear film is comprised of three layers that work together to provide lubrication and nutrients to the front surface of the eye as well as protect the eye from infection and environmental irritants:
The Mucous Layer: The innermost layer, which helps to spread the tear evenly over the surface of the eye.
The Aqueous Layer: The middle and largest layer, which contains a dilute salt water solution
The Lipid Layer: The outermost layer, which helps to decrease evaporation of the aqueous layer.
If there is a lack of tear production or a problem with any of these three layers (e.g., a lack of sufficient moisture, tears are not spread evenly, or tears evaporate too quickly), Dry Eye symptoms may occur.
Although anyone can have Dry Eye, it most commonly affects people over the age of 50. It is especially common in postmenopausal women due to hormonal changes that effect tear quality and tear production.