Understanding Dry Eye
The Sticky Foundation
The mucin (mucous) layer at the bottom of the tear film provides a “sticky” foundation and acts as a barrier to the eye surface.
The Watery Center
The aqueous layer is the “juicy” center that is comprised of tears produced by the lacrimal glands.
The Oily Top
Finally, the top “oily” lipid layer of the tear film is made up of lipids or oils produced from the meibomian glands. The lipid layer is necessary for a stable tear film and keeps the aqueous layer from evaporating.
The tear film is a complex structure of mucin, tears and oil that protects the surface of the eyes. When the tear film is compromised, it results in a variety of symptoms, most of which have been associated with Dry Eye and MGD (Meibomian Gland Dysfunction). Understanding the tear film is key to seeing the clear differences between tear deficiency issues and MGD, especially since MGD is more common and has greater long term impact on Dry Eye symptoms.
The Leading Cause of Dry Eye Symptoms: Blocked Glands in the Eyelids
Fortunately, many dry eye patients enjoy healthy tear production that, in some, can be evidenced by a common dry eye symptom, excessive tearing, the eyes response to combat irritation and dryness. If your tear production is healthy, your eye care professional should check meibomian gland function and structure to determine if the protective tear film oil is being properly produced and spread on the surface off your eye.
While MGD is most often detected in adults over 40, the condition does not discriminate based on age and has also been seen in kids and young adults. That is why checking for MGD should be a part of a regular eye exam. MGD, if caught early, may play a significant role in avoiding chronic dry eye symptoms and to prevent the potential for permanent gland loss.
Normal Gland Structure
Gland Shortening and Loss
Significant Gland Loss
Severe Gland Loss