Dry eye syndrome is triggered by a chronic lack of enough lubrication and moisture on the surface area of the eye. Consequences of dry eyes range from subtle however constant eye inflammation to significant inflammation as well as scarring of the front surface of the eye.
In addition to being called dry eye syndrome, dry eye disease, or just “dry eye,” alternative medical terms used to describe dry eyes consist of:
- Keratitis sicca. Generally used to explain dryness and inflammation of the cornea.
- Keratoconjunctivitis sicca. Used to describe dry eye that impacts both the cornea and the conjunctiva.
- Dysfunctional tear syndrome. Used to emphasize that inadequate quality of tears can be just as important as inadequate quantity.
Dry eye syndrome can likewise be partitioned into pure aqueous shortage dry eye and evaporative dry eye. Eighty-six percent of patients with dry eye syndrome also have signs of meibomian gland dysfunction.
Dry Eye vs. Dry Eye Syndrome
Dry eyes are very common, and dry eye syndrome is a significant factor for sees to the eye doctor. A recent online survey revealed that almost half (48 percent) of Americans age 18 and older frequently experience dry eye symptoms.
Also, results from a 2012 Gallup survey show that more than 26 million Americans experience dry eyes, and this number is expected to increase to more than 29 million within 10 years.
Other sources estimate that almost five million Americans age 50 and older have medically significant dry eye syndrome, and dry eyes affect almost two times as numerous women as men.
Dry Eye Symptoms
Symptoms of dry eyes and dry eye syndrome include:
- Burning feeling
- Itchy eyes
- Aching experiences
- Heavy eyes
- Fatigued eyes
- Sore eyes
- Dryness experience
- Red eyes
- Photophobia (light sensitivity)
- Blurred vision
Another typical symptom is something called a foreign body feeling– the feeling that grit or some other object or product is “in” your eye.
And as odd as it may sound, watery eyes also can be a symptom of dry eye syndrome. This is because dryness on the eye’s surface area in some cases will over-stimulate production of the watery element of your tears as a protective system. But this “reflex tearing” does not stay on the eye enough time to correct the underlying dry eye condition.
In addition to these symptoms, dry eyes can cause swelling and (in some cases long-term) damage to the surface area of the eye.
What Causes Dry Eye Syndrome?
A sufficient and constant layer of tears on the surface area of the eye is essential to keep your eyes healthy, comfortable and seeing well. Tears shower the eye’s surface area to keep it moist and wash away dust, debris and bacteria that could harm the cornea and cause an eye infection.
A typical tear movie includes 3 important parts:
- An oily (lipid) component
- A watery (liquid) element
- A mucous-like (mucin) part
Each part of the tear movie serves a crucial function. For instance, tear lipids assist keep the tear film from evaporating too quickly and increase lubrication, while mucin helps anchor and spread out the tears across the surface of the eye.
Each tear component is produced by various glands on or near the eye:
- The oily element is produced by meibomian glands in the eyelids.
- The watery element is produced by lacrimal glands located behind the external aspect of the upper eyelids.
- The mucin element is produced by goblet cells in the conjunctiva that covers the white of the eye (sclera).
A problem with any of these sources of tear film components can result in tear instability and dry eyes, and there are different classifications of dry eyes, depending on which component is affected.
For example, if the meibomian glands do not produce or secrete sufficient oil (meibum), the tear movie might evaporate too quickly– a condition called “evaporative dry eye.” The underlying condition– called meibomian gland dysfunction– is now acknowledged as a considerable factor in numerous cases of dry eye syndrome.
In other cases, the main reason for dry eye is a failure of the lacrimal glands to produce adequate watery fluid (liquid) to keep the eyes adequately moistened. This condition is called “aqueous shortage dry eye.”.
The specific kind of dry eye frequently will identify the kind of treatment your eye doctor advises to provide you remedy for your dry eye symptoms.