Dry eye disease is a common condition that occurs when your tears aren't able to provide adequate lubrication for your eyes. Tears can be inadequate and unstable for many reasons. For example, dry eyes may occur if you don't produce enough tears or if you produce poor-quality tears. This tear instability leads to inflammation and damage of the eye's surface.
Dry eyes feel uncomfortable. If you have dry eyes, your eyes may sting or burn. You may experience dry eyes in certain situations, such as on an airplane, in an air-conditioned room, while riding a bike, or after looking at a computer screen for a few hours.
Your tear film has three essential layers that work together to keep your eyes lubricated, smooth, and clear:
1. Fatty Oils (Lipid Layer)
The outer layer of the tear film is produced by the meibomian glands in your eyelids. This oily layer prevents tears from evaporating too quickly and helps keep the tear surface smooth.
2. Aqueous Fluid (Water Layer)
The middle layer is the thickest and is produced by the lacrimal glands. This watery layer cleanses the eye and washes away foreign particles or irritants.
3. Mucus (Mucin Layer)
The inner layer is produced by goblet cells in the conjunctiva. This mucus layer helps spread the watery layer evenly over the eye's surface and helps tears stick to the eye.
Problems with any of these layers can cause dry eyes and lead to discomfort and vision problems.
Types of Dry Eye Disease
This type occurs when your lacrimal glands don't produce enough of the watery component of tears to maintain a healthy eye surface.
Also called keratoconjunctivitis sicca (KCS), this is often associated with autoimmune conditions like Sjögren's syndrome.
This is the most common type, occurring when tears evaporate too quickly due to problems with the oil (lipid) layer of the tear film.
Often caused by meibomian gland dysfunction (MGD), where the glands that produce the oily layer become blocked or don't function properly.
How Common is Dry Eye?
Dry eye disease is one of the most common eye conditions, affecting millions of people worldwide. In the United States alone, approximately 16 million Americans have been diagnosed with dry eye disease.
The condition becomes more common with age, particularly affecting people over 50. Women are more likely to develop dry eye than men, especially during and after menopause due to hormonal changes.
Beyond the physical discomfort, dry eye disease can significantly impact quality of life, making it difficult to perform everyday activities such as reading, driving, working on a computer, or watching television.
If left untreated, dry eye disease can lead to more serious complications:
- Eye infections: Tears protect the surface of your eyes from infection. Without adequate tears, you have an increased risk of eye infection.
- Damage to the eye surface: Severe dry eyes may lead to eye inflammation, abrasion of the corneal surface, corneal ulcers, and vision loss.
- Decreased quality of life: Dry eyes can make it difficult to perform everyday activities and reduce your overall well-being.
The good news is that effective treatments are available. With proper diagnosis and management, most people with dry eye disease can find significant relief.