What is Dry Eye? How is Dry Eye Treated?

Dry eye is an eye disorder that occurs as a result of insufficient tears or inability to provide sufficient lubrication in the eye. Tears are the liquid that is constantly produced and keeps the surface of the eye slippery, moist and clean. In this way, it helps to provide clear and smooth vision and protect the eyes against infections. However, in some cases, problems may occur in the production, function or quality of tears and the eyes may be directly affected. Tear production and function may be inadequate due to many reasons. Factors such as change in tear quality, aging, problems in tear production, medications and infection can negatively affect tear production. Insufficient and low quality tears; It may cause eye discomfort, burning, stinging, itching and inflammation. Dry eyes can negatively affect daily activities and social life, cause vision problems and pain, and cause redness. In addition, inflammation may occur in irritated eyes, in which case additional treatments may be required. There are various treatment methods used to control dry eyes and other related symptoms. It is important to determine the underlying cause in the treatment of dry eye (1).

dry eye

What is Dry Eye?

The moistness of the eyes is ensured by continuous tear production. As the eyelids close, tears spread to the cornea, the front layer of the eye. Tears help clear foreign matter from the eye, keep the eye surface smooth, reduce the risk of eye infections and provide clear vision. Eyes need a tear film to achieve clear and comfortable vision. The tear film layers are produced from different tear glands. The tear film that covers the surface of the eye and helps protect the eyes from external factors consists of 3 layers:

Oil layer:It is the outermost layer of the tear film. It helps prevent tears from drying out quickly and makes the tear surface smooth. This layer is produced in the meibomian glands.
Aqueous layer:It is the middle layer of the tear film. The aqueous layer, which makes up the majority of tears, helps clean the eye from foreign particles. This layer is produced in the lacrimal glands.
Mucus layer:It is the inner layer of the tear film. Mucus helps spread the watery layer on the surface of the eye. Without mucus, tears cannot adhere to the eye and the eye may not be able to stay moist. Mucus is produced in the conjunctiva. Conjunctiva is the transparent structure that covers the white of the eye and remains inside the eyelids.

In case there are more tears than normal in the eyes, the excess tears flow into small drainage channels towards the back of the nose with the help of channels located in the corners of the eyelids. Dry eyes can occur if one or more of the eye film layers are affected, the eyes are irritated, not enough tears are produced, and tear drainage is not balanced. Deterioration of the tear film structure may cause eye discomfort such as burning, itching, and watering (2, 3).

Causes of Dry Eye

In people with dry eyes, not enough tears can be produced or the quality of tears produced may be low. There are various conditions that can cause problems in tear production:

Inadequate tear production: Tear production may decrease due to factors such as aging, certain medications, and medical conditions. Wind, sun and dry climates can cause rapid evaporation of tears. When tear production decreases and tear evaporation accelerates, dryness may occur in the eyes.
Low quality tear production:The healthy tear structure consists of 3 layers. Oil, water and mucus layers play an important role in maintaining the function of tears. Missing one or more of these layers can cause poor tear quality. Poor quality tears may not spread optimally throughout the cornea and lead to dry eyes.
Aging: The natural aging process can cause decreased tear production in the eyes and cause dry eye symptoms.
Drugs:Antihistamines (allergy medications), blood pressure medications, decongestants and some antidepressant medications may negatively affect tear production.
Environmental conditions:Wind. Due to exposure to sun, smoke and dry climatic conditions, tear evaporation may accelerate and as a result, dryness may occur in the eyes. In addition, looking at phone, computer and television screens for a long time can also cause dry eyes. Medical conditions: The possibility of dry eye symptoms may be high in diseases such as diabetes, thyroid diseases and rheumatoid arthritis. In addition, dry eyes may occur as a result of inflammation in the eyelids or their surface.

In addition to common causes, women may be more likely to develop dry eye as a result of hormonal changes during pregnancy and menopause. Prolonged use of contact lenses can cause dry eyes. Additionally, LASIK surgery may also cause dryness in the eyes by negatively affecting tear production (3).

Symptoms of Dry Eye

Disruption or problems in the function of tears may cause dry eyes. Dry eyes cannot stay moist and can cause discomfort. Generally, dryness in the eyes can affect both eyes and the following symptoms may be observed:

Burning in the eye,
Itching in the eye,
Blurred vision,
Eye redness,
Stinging feeling in the eye,
Sensitivity to light,
Mucus accumulation in or around the eyes,
In the eyes foreign body sensation,
Watery eyes in response to dry eyes,
Difficulty wearing contact lenses,
Problems with night vision,
Eye fatigue.

Excessive watering may occur in dry eyes. The reason for this can be explained as irritated eyes producing more tears to correct this situation (1, 4).

Dry Eye Treatment

Dry eye treatment aims to provide and maintain normal tear quantity. Treatments are recommended to solve the problem that causes dry eyes. Primary options for treating dry eyes generally include using artificial tear solutions, increasing tear production, and providing anti-inflammatory treatment if inflammation is present. Main dry eye treatment options:

Artificial tear solutions can be used to increase tears. It can generally be preferred in mild dry eye cases to increase natural tear production. It may be recommended to use solutions that do not contain preservatives to prevent further irritation of the eyes. Additional treatments may be required for people who do not respond to artificial tear treatment.
The aim is to prevent the loss of naturally produced tears by protecting the tears. In this application, the channels through which tears flow are blocked. The tear ducts are closed with removable gel-like plugs or silicones. In this way, tears can be kept in the eye for longer and their loss can be prevented. In some cases, tear ducts can be closed permanently.
Tear drops that support tear production may be prescribed. Some nutritional supplements such as omega 3 recommended by the doctor may help tear production.
Prescription eye drops, ointments, cleansers, hot compresses and massage applications may be recommended to reduce inflammation in the eyelids or surface.

Hot compresses or eye masks can help relieve clogged oil glands. Additionally, massage of the eyelids with intense pulsed light therapy may contribute to relieving symptoms in people with dry eyes (3, 5).

How to Diagnose Dry Eye?

In the diagnosis of dry eye, an eye examination is performed, the medications used are evaluated, and tests measuring tear production are applied. People's general health problems, medications they use and environmental conditions they are exposed to are information that can be used to diagnose dry eye. During the physical examination of the eyes, the structure of the eyes and eyelids and blinking function can be checked. The cornea and eyelids can be examined with light examination. When there is a suspicion of abnormality in tear production, various tests can be applied:

Schirmer test: It is a test that measures tear production. Strips of paper are placed on the lower eyelids and left on the eye for several minutes. The tears produced in the eyes in response to the papers are evaluated according to the area covered by the paper strips.
Slit lamp examination:It helps to determine the amount of tears produced in the eyes. A light is shined on each eye and the eyes and eyelids are examined with the help of a microscope.
Tear film breakup test (BUT): It can be used to determine the evaporation rate of tears. Dye is applied to the eyes and it is determined how long the tear film remains stable.
Tear osmolarity test:The composition of water and particles in the tears is measured.

In addition, additional tests such as antibody tests may be recommended to investigate the presence of other underlying causes that cause dry eyes (3, 5).

what is dry eye

Computer Use and Dry Eye

Due to technological developments, the time spent in front of the screen has increased today. Staring at phone and computer screens for long periods of time can cause various eye disorders. Dry eye is one of these conditions and can cause irritation of the eyes. Typically, people blink every 10 seconds and the tear film is renewed. However, you may not blink frequently when looking at tablet, computer and phone screens. Working in front of a computer for long periods of time at home or at work can lead to dry eyes. In this case, it may be necessary to limit screen exposure time and increase eye and screen distance (6).

How to Rest the Eyes?

Home care recommendations can be given to rest the eyes, relieve irritation and keep the eyes moist. A damp cloth can be applied to reduce eye irritation and flaking and to loosen clogged sebaceous glands. Frequently soaking the cloth in warm/hot water can help soothe the eyes and loosen clogged oil passages. Hot compresses can be applied regularly every day. In addition to eye care and cleaning, paying attention to facial and hair care can reduce the likelihood of eye infections. Cleansing gels recommended by your doctor can be used with light massages.

According to studies, the use of omega 3 fatty acids, which can support the functioning of the oil-producing glands in the eyes, can reduce irritation. Omega-3 is found in walnuts, flaxseed, canola and soybean oils, and fatty fish such as salmon, tuna, sardines, trout and mackerel. In addition to natural foods, omega-3 oil and capsules can be used by consulting a doctor. Sunglasses can be used to prevent rapid evaporation of tears, and attention should be paid to the use of air conditioners, fans and hair dryers. The daily amount of water drunk can be increased and moisturizing filters can be used (7).