Meibomian Gland Dysfunction

Healthy eyes have a three layer tear film. First, a mucin layer is secreted by the conjunctival goblet cells. The second watery layer is secreted by lacrimal glands behind the upper eyelids. The third outer oily layer is secreted by Meibomian glands within the upper and lower eyelids.

The tear film keeps the outer surface of the eye and cornea moist, cleaned, healthy, and lubricated. For a variety of reasons, the Meibomian glands may fail to produce sufficient oil for the outer tear film layer. These glands may also become blocked. This is called Meibomian gland dysfunction.

All three tear film layers are important in transferring oxygen to the cornea. Without an adequate oily layer due to MGD, the watery layer underneath can evaporate more readily. This can lead to dry eye, irritation, inflammation, and other conditions.

Treatment

Medications & Tears

Over-the-counter artificial tears may reduce the symptoms of minor cases of dry eye. Your eye care provider may prescribe special eye drop medications.

Punctal Plugs

Another approach to treat dry eye involves the insertion of very small punctal plugs. They are placed in the openings where your tears normally drain into the lacrimal sac. This may help retain existing moisture on the surface of your eyes.

Heat Treatments

Heat therapy may be used to unblock and treat Meibomian glands to improve their oil production. Some therapies provide a thermal barrier under the eyelids to protect the eye globe during treatment. Heat is applied to the eyelids to liquify any thickened oil. Then, gentle pressure motion is applied to express the oils and unblock glands. These treatments do not regenerate nor restore “dropped out” glands.

What are “dropped out” Meibomian glands?

When we blink, oil is secreted and then spread on top of the watery tear film layer. Healthy glands produce an adequate supply of oil. These glands may degenerate and totally cease to produce oil. This is known as “dropout” of the glands. The remaining glands may not provide enough oil.

Dropout Effects

Meibomian glands that have “dropped out” cannot return or regenerate. Gland dropout results in a reduction in the overall amount of oil available for the tear film. When blinking, an insufficient amount of protective oil is secreted. The watery tear layer underneath will then evaporate more quickly. This leads to dry eye, irritation, inflammation, and other conditions.

Summary

Any changes to your eyes, eyelids, or vision should be brought to your eye care provider’s attention immediately.