THE ROLE OF THE TEAR FILM:
A healthy tear film lubricates and moisturizes the surface of the eye. It also has an important role in clearing away debris and protecting against infections. The lipid, or oil layer, prevents evaporation of the tears, while the water layer provides most of the lubrication. The mucin layer is the innermost layer and is produced by the cells in the conjunctiva (the clear skin that lines the eye). This mucus helps the overlying
watery layer to spread evenly over the eye.
WHAT IS DRY EYE SYNDROME?
Dry eye syndrome (DES) is a result of a deficiency in any or all of the layers of the tear film. Common causes include aging, hormonal changes, medications, and environment, although often a cause cannot be found. Common symptoms of dry eye include:
- Blurred vision
Many think that their eyes cannot be dry if they are watery. However, the excess tearing is a reflex due to irritation of the surface of the eyes and is not adequate to protect and lubricate the surface.
HOW IS DRY EYE TREATED?
The mainstay of treatment is artificial tear drops. These can be used multiple times per day, although if used more than 4-6 times per day, a preservative-free preparation should be considered. Tear ointments (such as Lacrilube) may help and are best used at bedtime because of the blurring that they cause. Additional conservative measures that may help dry eye include warm compresses and eyelid scrubs (either with baby shampoo or with a commercially prepared product) to help the lipid/oil component of the tear film and prevent evaporation. An Omega-3 supplement may also help the lipid component of the tear film.
If the above methods are not sufficient, then Restasis drops or punctal plugs may be an option. Restasis is a twice daily drop, which acts to decrease the inflammation on the surface of the eye and help the eye produce tears. Punctal plugs are tiny silicone plugs that are placed in the tear duct opening on the eyelids. They prevent the tears from draining from the surface of the eye, thereby keeping them on the surface for lubrication.