dry eye syndrome

Do you suffer from dry eyes? Learn all about
dry eye syndrome

Dry eye syndrome is caused by a chronic lack of sufficient lubrication and moisture on the eye’s surface. The consequences of the dry eye range from mild but constant eye irritation to significant inflammation and even the appearance of scars on the eye’s front surface.

In addition to being called dry eye syndrome, dry eye disease, or simply “dry eye,” there are more terms to describe dry eye, such as:

Sicca keratitis. They are generally used to describe the dryness and inflammation of the cornea.

Keratoconjunctivitis sicca. It is used to describe dry eye, which affects both the cornea and the conjunctiva.

Lacrimal dysfunction syndrome. Used to emphasize that inadequate tear quality can be just as important as inadequate tear quantity.

Dry eye prevalence

Dry eye is very common, and dry eye syndrome is a primary reason for consultation with eye care professionals. A recent online survey revealed that nearly half (48%) Americans age 18 and older regularly experience dry eye symptoms.

Additionally, the results of a 2012 Gallup poll show that more than 26 million Americans suffer from dry eye, and this number is estimated to increase to more than 29 million within 10 years.

Other sources estimate that nearly 5 million Americans age 50 and older have dry eye syndrome as an important clinical condition, and dry eye affects nearly twice as many women as men.
Dry eye symptoms

Symptoms of dry eye and dry eye syndrome include:

Burning sensation

Itchy eyes

Painful sensations

Heaviness in the eyelids

Fatigued eyes

Sore eyes

Feeling of dryness

Red eyes

Photophobia

Blurry vision

Another common symptom is a “foreign body sensation” – the sensation of having grit or some other object or material “inside” the eye.

And although it seems weird, watery eyes can also be a symptom of dry eye syndrome. This is because the dryness of the eye’s surface sometimes overstimulates the production of the aqueous component of tears as a protective mechanism. But this “tear reflex” does not stay in the eye long enough to correct the underlying dry eye disorder.

In addition to these symptoms, dry eye can cause inflammation and damage (sometimes permanent) to the surface of the eye.

Dry eye syndrome can also affect the results of LASIK surgery and cataract surgery.
It would help if you had tears to moisturize your eyes and remove particles that have gotten in. A healthy tear film in the eye is necessary for good vision.

Dry eyes occur when the eye is unable to maintain a healthy layer of tears.
Causes

Dry eye regularly occurs in people who are otherwise in good health. It becomes more common with age. This can occur due to hormonal changes that cause the eyes to produce fewer tears. The dry eye symptom can sometimes be caused or made worse by meibomianitis, which changes the normal tear film.

Other common causes of dry eyes include:

Dry environment or workplace (windy, air-conditioned)
Sun exposure
Smoking or second-hand smoke
Cold or allergy medicine
Wear contact lenses

Dry eye can also be caused by:

Heat or chemical burns
Previous eye surgery
Using eye drops for other eye diseases

What Causes Dry Eye Syndrome?

To keep the eyes healthy, with good vision and without discomfort, they must have an adequate and uniform tear layer. Tears wash the eye’s surface to keep it moist and remove dust, debris, and microorganisms that could damage the cornea and lead to an eye infection.

A normal tear film is made up of three important components:

An oil component (lipid)

A component of water (aqueous)

A mucous component (mucin)

Each component of the tear film serves a fundamental purpose. For example, lipids in tears help prevent the tear film from evaporating too quickly and increase lubrication, while mucin helps fix and spread tears across the surface of the eye.

Each tear component is produced by different glands of the eye or close to it:

The meibomian glands of the eyelids produce the oil component.

The watery component is produced by the lacrimal glands located behind the outer side of the eyelids superiores.

The mucin component is produced by the goblet cells of the conjunctiva that cover the white of the eye (sclera).

Any problem with one of these sources of tear film components can result in tear instability and dry eyes, and there are different categories of dry eye, depending on the component that is affected.

For example, if the meibomian glands do not produce or secrete enough oil (meibum), the tear film may evaporate too quickly, a condition called “evaporative dry eye.” The underlying disorder – called meibomian gland dysfunction – is now recognized as a significant factor in many cases of dry eye syndrome.

In other cases, the root cause of dry eye is a failure of the lacrimal glands to produce enough watery fluid to keep the eyes adequately moisturized. This condition is also called “watery, dry eye deficiency,”:

The specific type of dry eye will usually determine the type of treatment your eye care professional recommends to relieve dry eye symptoms.

Factors associated with dry eye syndrome

Several factors can increase the risk of dry eyes. These include:
Computer use

When we use a computer or smartphone and other portable digital devices, we tend to blink less deeply and less frequently, leading to more tear evaporation and an increased risk of dry eye symptoms.
Wearing contact lenses

While it can be difficult to determine the exact extent to which contact lenses contribute to dry eye problems, the discomfort of this condition is a primary reason people stop wearing them.
Aging

Dry eye syndrome can appear at any age, but it becomes more and more common as time goes on, especially after the age of 50.
Menopause

Postmenopausal women face a higher risk of dry eye than men of the same age.
Indoor environments

Air conditioning, ceiling fans, and air injection heating systems can lower indoor ambient humidity and accelerate tear evaporation, leading to dry eye symptoms.
Outdoor environments

Arid climates and windy or low-humidity conditions increase the risks of dry eye.
Frequent flights

The air in aircraft cabins is extremely dry and can cause dry eye problems, especially those who fly frequently.
Smoke

In addition to dry eyes, smoking is associated with serious eye problems such as macular degeneration, cataracts, and uveitis. (For details, see our article on why smoking is bad for your eyes.)
Healthy conditions

Certain systemic diseases, such as diabetes, thyroid-related disorders, lupus, rheumatoid arthritis, and Sjogren’s syndrome, contribute to dry eye problems.
Medicines

Many prescription and over-the-counter medications, including antihistamines, antidepressants, certain blood pressure drugs, and birth control pills, increase the risk of dry eye symptoms.
Eyelid problems

Incomplete closing of the eyelids when sleeping or blinking, a disorder called lagophthalmos, can be caused by aging or after a plastic blepharoplasty, as well as other causes, can lead to the severe dry eye that, if left untreated, could lead to a corneal ulcer.

Likewise, LASIK and other corneal refractive surgeries can sometimes cause dry eyes. In most cases, however, dry eye discomfort after LASIK surgery is temporary and resolves within a few weeks after the procedure.

Suppose you suffer from the dry eye before LASIK surgery. In that case, your eye care professional may recommend a treatment regimen for this condition before the procedure to ensure the best results with LASIK surgery.