What are Dry Eyes?
Dry eyes are a common eye condition that can occur for a variety of different reasons.
When your tear glands are not producing enough tears to keep your eyes comfortably lubricated, it is known as aqueous tear deficiency. If your tear components are poorly balanced and evaporate too quickly to keep your eyes comfortable, it is known as evaporative dry eye disease.
The surface of your eyes are covered by a “tear film.” The tear film houses the nutrients your eyes need to stay hydrated and comfortable. However, if any blockages or damage impact the glands that produce these nutrients, it can lead to dry eye symptoms.
The tear film has 3 distinct layers:
- Mucin makes up the innermost layer of the tear film. It’s responsible for making sure the rest of the tear film is spread evenly across the surface of your eyes.
- The aqueous layer is the middle layer of your tear film. This layer is responsible for keeping your eyes hydrated and washing away any foriegn particles that may land on your eyes.
- Oil or meibum is what the outermost layer of your tear film consists of. This layer is responsible for sealing in the rest of the tear film and preventing it from evaporating.
A few different glands around your eyes produce your tear film, namely the lacrimal and meibomian glands. However, if these glands become blocked or damaged, it could impact the creation and quality of the tear film layers, leading to dry and uncomfortable eyes.
Meibomian Gland Dysfunction (MGD)
Optometrists can diagnose meibomian gland dysfunction by monitoring the rate of gland secretion and the quality of the meibum produced. If these glands are blocked or damaged, it can prevent a healthy oil layer from developing, leading to discomfort.
Blockages in your meibomian glands and inflammation can also lead to blepharitis. When this happens, your eyelids can become red and swollen, which could lead to dandruff-like scales on the edges of your eyelids and even eyelash loss.
Other Common Causes of Dry Eyes
Other common causes include:
- Poorly fitted contact lenses
- Medical conditions like rheumatoid arthritis, lupus, diabetes, and Sjorgen’s Syndrome
- Laser eye surgery (Dry eyes are a common side-effect during the healing process. If your symptoms are more severe or persist longer than expected, please speak to your optometrist.)
Common dry eye symptoms include:
- A gritty, stinging, or burning sensation
- Sensitivity to light
- Stringy mucus or discharge in or around your eyes
- Blurry vision