Dry eyes

Dry eyes are a symptom that most of us have experienced. This condition is also known as dry eye syndrome or xerophthalmia. Dry eyes occur when the lacrimal gland does not produce enough fluid. As a result, the composition of the tear film on the surface of the cornea is disturbed, its properties change, causing serious discomfort in a person: the illusion of “sand in the eyes”, pain, burning, a feeling of “tightness”, inflammation and decreased vision.

It was previously believed that dry eye is a disease that mainly affects the elderly. However, in recent years, dry eye syndrome has significantly “younger”. Young people who are forced to spend a lot of time at the computer complain about drying out of the eyes. Also, the problem is often faced by those who use the means of contact vision correction, especially in conditions of increased dryness of the air or strong winds.

The structure of the tear film

The essence of xerophthalmia is insufficient moistening of the surface of the eye with the help of the tear film, which is formed by the tear fluid. Due to the fact that the film becomes less dense, and its composition changes, the cornea of ​​​​the eye dries up. The result is a feeling of dryness and irritation. Eyes begin to react painfully to dry air, wind, cigarette smoke. There can be many reasons for the violation of normal hydration of the eyes.

Recall that the tear film includes three layers. The main one is medium, which is 98% water, and also includes salts and proteins. This layer is called the watery layer and it is this, in fact, that we call tears that appear in the eyes during crying or laughter. The lacrimal glands, which are located at the outer edge of the eye, create a watery layer. They constantly secrete a small amount of lacrimal fluid. When blinking, this fluid is distributed over the entire surface of the eye.

At the edges of the eyelids are small meibomian glands that secrete fats (lipids). They form the outer layer of the tear film. Lipids do not allow moisture to evaporate from the aqueous layer, acting as a natural protective barrier. In addition, it is thanks to them that the surface of the tear film becomes smooth and the light rays passing through it are refracted at the right angle.

Finally, the thin transparent membrane of the conjunctiva, which covers the inner surface of the eyelid and the sclera of the eye, secretes a mucous substance that forms the so-called mucin layer. It helps to smooth out all the micro-irregularities on the surface of the cornea and helps the tear fluid to be evenly distributed over the surface of the eye. After the lacrimal fluid washes the surface of the organs of vision, it enters the lacrimal sac through the lacrimal canaliculi, and then into the nasal cavity.

There are many factors that lead to dry eyes. Traditionally, they are divided into two groups depending on the pathogenetic mechanism that “triggers” the development of the “dry eye syndrome”. The first group are pathological conditions associated with a decrease in the production of tear fluid or its release, and the second are factors that lead to a decrease in the stability of the precorneal tear film.

Causes of decreased tear production

This group includes several reasons at once: failures in the activity of the immune system (Sjögren’s syndrome, transplant rejection, complications after radiotherapy of the head and neck); diseases of the hematopoietic system (malignant tumors, anemia, etc.); endocrine disorders (hypothyroidism, diabetes mellitus, menopause), infectious diseases (HIV, cholera, tuberculosis, etc.), dermatological problems (neurodermatitis, dermatitis, etc.).

Autoimmune diseases

The essence of autoimmune diseases is that there is a failure in the process of recognition by cells of the immune system of body tissues, which begin to be perceived as foreign. As a result, an abnormal immune response develops, the target of which is healthy tissues and organs.

The most common condition associated with xerophthalmia is Sjögren’s syndrome or disease. It can be either primary or secondary. Primary Sjögren’s syndrome is manifested by an autoimmune lesion of the salivary and lacrimal glands, and in the secondary syndrome, which manifests itself several years after the onset of the disease, there are problems with the connective tissue (systemic lupus erythematosus, primary biliary cirrhosis, etc.).

Sometimes dry eye syndrome develops as a complication after radiation therapy of the neck and head due to the fact that the tissue of the lacrimal gland is also irradiated. Its structure undergoes changes, and the immune system begins to attack it as a foreign one.

In addition, an autoimmune response may develop after corneal transplantation from a donor.

Diseases of the hematopoietic system

Scientists were able to establish that there is a connection between a decrease in the functions of the lacrimal gland and a number of diseases of the hematopoietic system. In particular, tear production is reduced in hemolytic anemia, lymphoma, lymphosarcoma, lymphocytic leukemia, and other diseases.

endocrine disorders

The purpose of the endocrine system is to maintain the stability of the internal environment of the body due to the release of hormones into the blood. “Breakdown” in the operation of this system is always the cause of violations in the work of a number of organs.

Dry eyes can occur with diabetes mellitus, hypothyroidism, and also in women during menopause. So, with diabetes, the secretion of the lacrimal glands decreases. Insufficient secretion of tear fluid leads to a feeling of discomfort and “sand” in the eyes.

Hypothyroidism is an insufficient production of thyroid hormones. It is accompanied by a decrease in the secretion of exocrine glands: lacrimal and salivary. That is why patients with hypothyroidism often complain of dry eyes.

Finally, menopausal syndrome occurs in women after the cessation of the production of estrogen and progesterone in the body. It is often accompanied by mood swings, insomnia, general malaise, “jumping” pressure, as well as a violation of the secretion of the lacrimal glands.

Infectious diseases

Infectious diseases are usually accompanied by a syndrome of general intoxication. As a rule, this raises the body temperature and may begin dehydration. In this case, the reserves of the lacrimal gland are depleted and its secretion is reduced.

Dermatological diseases

Xerophthalmia is a symptom that accompanies a number of skin diseases. These are congenital ichthyosis, herpetic dermatitis, neurodermatitis, etc.

Congenital ichthyosis is manifested by thickening of the skin, which begins to peel off with plates resembling fish scales. In addition to changes in the relief of the skin, there is itching of the eyes and a violation of the secretion of the lacrimal glands.

Neurodermatitis is an allergic-immunological disease that affects the mucous membranes and skin. In addition, the functioning of the autonomic nervous system, which is involved in the functioning of the lacrimal glands, is disrupted. As a result, the secretion of tear fluid is significantly reduced.

Herpetic dermatitis is a lesion of the skin and mucous membranes with the herpes simplex virus. If herpes vesicles are localized in the eye area, they can spread to the conjunctiva and the lacrimal gland.

Causes of reduced tear film stability

A decrease in the thickness of the tear film and a decrease in its stability can be caused by a number of reasons: both related to a person’s lifestyle and caused by disturbances in the functioning of internal organs and body systems.

Corneal scars

Often, as a result of the presence of foreign bodies in the eye or as a result of corneal tuberosity associated with the presence of postoperative scars, the tear film becomes thinner and ruptures, resulting in xerophthalmia.

Neuroparalytic keratitis

This is inflammation of the cornea, which leads to the fact that its sensitivity is reduced. In a normal state, a person blinks, moistening the eye, when he feels irritation of the cornea due to the thinning of the tear film. If the cornea loses sensation, the patient’s brain does not receive the signal to blink, and the surface of the eye remains dry for a long time. As a result, inflammation, clouding of the cornea and a significant decrease in vision develop.

Incomplete closure of the eyelids

Sometimes the eyelids simply do not match the size of the eye. This condition is called lagophthalmos and can be either congenital or appear after surgery. In addition, there is also exophthalmos – protrusion of the eyeballs, which also provokes incomplete closure of the eyelids. This condition is often observed in patients with hyperthyroidism, and may also be the result of trauma or a tumor process.

In patients suffering from incomplete closure of the eyelids, even during sleep, part of the cornea remains open, which provokes the development of xerophthalmia.

Allergy

Allergy is a sharp reaction of the immune system to the contact of the body with any substance. Allergens are most often plant pollen, citrus fruits, pet hair, dust mites, etc.

When the allergen enters the mucous membrane of the nose or eyes, its swelling develops. The patient complains of a feeling of “sand” in the eyes, discomfort, the illusion of a foreign body on the mucosa.

Stagnation of tear fluid

In the normal state, the lacrimal fluid, having been on the surface of the cornea and moistened it, moves to the inner corner of the eye when blinking and enters the nasal cavity through the system of lacrimal ducts. In the event that these tubules fail due to the inflammatory process, lacrimal fluid stagnates and its chemical composition changes. Bacteria begin to multiply in it and dust particles settle, which irritate the mucous membrane, causing the eyes to dry out.

Using air heaters

Under normal temperature and humidity conditions, moisture evaporates from the surface of the eyes in about 10 seconds. After that, the person blinks, closing the eyelids and moistening the eyes with tear fluid. However, if the air temperature rises and its humidity decreases, moisture from the surface of the eyes begins to evaporate faster. Therefore, people often experience discomfort while in a room where an air heater or air conditioner is operating.

Prolonged work at the monitor

Scientists have proven that when a person works at a monitor, he blinks at least half as often. As a result, the cornea inevitably dries up and dry eye syndrome develops.

Use of contact lenses

Contact correction involves placing lenses on the cornea that help improve visual acuity. Ideally, the lenses should fully match the size of the cornea and repeat its shape. However, often contact correction products provoke passive irritation of the conjunctiva, causing the eyes to dry out. This is fraught with the development of keratoconjunctivitis.

Use of low-quality cosmetics

Unscrupulous manufacturers of cosmetics in the low price segment often use substances that are similar in their characteristics to those used for the production of expensive counterparts, but differ from them in quality characteristics. As a rule, such cosmetics have a number of side effects. In particular, poor quality mascara, eyeliner and eye shadow can cause contact dermatitis or conjunctivitis and provoke the development of “dry eye syndrome”.

Pregnancy

Often xerophthalmia develops in ladies in an “interesting position”. Why this happens, doctors have not yet fully understood. As one of the reasons, a change in the hormonal background and an increase in temperature are considered.

Side effects of some drugs

Sometimes medications can trigger xerophthalmia. A number of medications, if used for a long time, can cause a feeling of drying out of the surface of the eye or aggravate already existing discomfort. These drugs include diuretics, some antidepressants, oral contraceptives, antihistamines, beta-blockers, peptic ulcer drugs, etc.

Symptoms of xerophthalmia

Dry eye is a problem that comes with many symptoms.

1. Feeling of discomfort. It may seem to the patient that there is some kind of foreign body in the eye (“sand” and “mote”). There is also irritation, burning, pain, photophobia.
2. A person complains that periodically the image seems to become fuzzy, blurry. Most often, the quality of vision decreases towards the end of the day.
3. Photophobia. Bright light causes discomfort, tearing, burning sensation.
4. Poor tolerance of wind, smoke, air-conditioner air flow, etc.
5. Patients resorting to contact vision correction tools complain that the lenses suddenly become uncomfortable. They begin to be perceived as a foreign body, they can even cause pain.
6. “Adhesion” and slow opening of the eyelids.

How is dry eye diagnosed?

The diagnosis of dry eye is usually made by an ophthalmologist based on the symptoms. At the same time, given the fact that “dry eye syndrome” may indicate another disease (for example, Sjögren’s syndrome), the doctor may conduct a more detailed examination and history taking.

In order to confirm that a person really suffers from “dry eye syndrome”, a special study is carried out – the Schirmer test.

This study is also known as the Schirmer test.

Carry out the test as follows. The doctor takes a strip of filter paper measuring 5 × 50 mm, bends the end of it and leads it over the edge of the lower eyelid. The patient is asked to close their eyes. After that, the strip should absorb the precorneal tear film and fluid from the lacrimal canal for five minutes. In the event that the patient suffers from dry eyes, the amount of tears absorbed by the paper may be negligible or zero. If the tear film is significantly thinned, the Schirmer test will show an extremely low result. In this case, the paper is considered to be wetted by 10 mm in 5 minutes.

It is noteworthy that this test can be performed both with local anesthesia and without it. In the event that the doctor suspects that the patient has a “dry eye syndrome”, the paper, in contact with the conjunctiva, can cause reflex lacrimation, which “masks” this problem. To prevent such a possibility, an anesthetic is instilled into the eye a few minutes before the test, as a result of which reflex lacrimation is eliminated.

Another way to study when making a diagnosis of dry eye syndrome is the Norn test. A 0,2% solution of fluorescein is instilled into the upper region of the patient’s eyelids. After that, the patient should blink once. Next, it is examined, recording the time between the opening of the eyelids and the rupture of the precorneal tear film. If it breaks earlier than after 10 seconds, we can talk about the patient’s predisposition to dry eyes.

An ophthalmologist may also recommend laboratory tests to help definitively identify the cause of dry eyes. So, a cytology of a scraping or an imprint of the conjunctiva, an immunological study of the lacrimal fluid and its crystallography, which helps to identify the type of eye disease, can be carried out.

Also, the doctor may insist on conducting narrowly focused studies. They will help identify diseases, one of the secondary symptoms of which is dry eyes. This may be a general analysis of blood and urine, which will help identify anemia, inflammation and kidney disease; determination of immune complexes circulating in the blood, an increase in the number of which is a sign of autoimmune diseases; conducting rheumatic tests; determining the level of thyroid hormones to exclude hypothyroidism; blood sugar test to rule out diabetes; determination of antibodies to the herpes virus.

An ophthalmologist can also use instrumental research methods that make it possible to study the structure and properties of the lacrimal fluid. So, thiascopy can be performed – the study of the structure of the tear film, the density of the mucous, watery and lipid layers. The osmolarity of the tear fluid, which is an important factor influencing the strength of the tear film, may also be examined.

Dry eye treatment can be medical or surgical. Surgery is used when medical methods fail. As a rule, surgical treatment is aimed at correcting defects of the cornea or eyelids, as well as eliminating complications resulting from the “dry eye syndrome”.

Drug treatment of xerophthalmia

Drug therapy is the first step in the treatment of xerophthalmia. Its duration depends on how effective the treatment is. In the course of drug therapy, a number of drugs are used.

Artificial tears

To compensate for the deficiency of one’s own tear fluid, “artificial tears” preparations can be used. Their density and composition vary. If the disease is mild, the use of eye drops is recommended.

In the event that the form of the disease is moderate and severe, the drug should be on the cornea for a longer time. Therefore, it is recommended to use medicines in the form of ointments or gels, for example, Oftagel.

Oftagel – a drug with carbomer in the maximum concentration. It has the effect of long-term moisturizing, eliminates lacrimation and does not require frequent instillations. Moreover, the gel can be used once at any time of the day, which eliminates the need to use drops several times a day. Oftagel is suitable for people with complaints of periodic dry eyes and irritation.

Anti-inflammatory drugs

Anti-inflammatory drugs are one of the most widely used groups of drugs in the treatment of ocular pathologies. Stopping the inflammatory process, they at the same time prevent the development of “dry eye syndrome”. Many of these drugs are combined, combining anti-inflammatory and antibacterial effects.

Metabolic drugs

Metabolic preparations are usually ointments that should be applied to the lower eyelid several times a day. These funds help to increase the content of pantothenic acid in the tissues of the eye, which takes part in metabolism, increases the regenerative properties of cells and helps to normalize the production of tear fluid.

Antihistamines

Antiallergic drugs help to stop an allergic reaction in the body, which can manifest itself, including discomfort and a feeling of “sand” in the eyes.

Antibiotics

Antibacterial drugs are used in ophthalmology quite often, because even if the inflammatory process is not of a bacterial nature, there is always a risk of a bacterial infection. Most often, antibiotics are used in the form of topical ointments.

Surgical treatment of dry eye syndrome

Surgical intervention is resorted to in situations where drug therapy has exhausted its reserves and has not been effective enough.

There are several types of surgical interventions that are used for “dry eye syndrome”.

Blockage of the tear ducts

In order for tear fluid to accumulate in the vaults of the eyelids, a blockage of the lacrimal ducts can be performed. As a result, when blinking, the cornea begins to be washed by tears more effectively. Most often, this surgical intervention involves blockage of the lacrimal openings with special plugs, as well as their coagulation using a laser beam or an electric scalpel.

Reducing the area of ​​evaporation of tear fluid

Sometimes doctors resort to stitching the edges of the eyelids, as a result of which the palpebral fissure narrows. This helps to reduce the area of ​​tear fluid evaporation. As a rule, this intervention is carried out if a simple blockage of the lacrimal ducts did not help normalize the secretion of the lacrimal glands.

Implantation of additional lacrimal glands

An extremely difficult, but at the same time effective method of treating xerophthalmia is the transplantation of additional mucous glands. They are implanted from the patient’s oral cavity into the soft tissues of the appendages of the organs of vision. The effectiveness of this surgical intervention depends mainly on the skill of the surgeon.

Treatment of complications of xerophthalmia

“Dry Eye Syndrome” is not a “harmless” disease at all. In severe cases, it can lead to corneal ulcer and perforation. In this case, tissue flaps are transplanted from the conjunctiva and oral mucosa, the purpose of which is to promote the healing of ulcers. This operation is very serious and its success depends on how experienced the surgeon performs it.

Folk remedies for the treatment of xerophthalmia

For the treatment of “dry eye syndrome”, some remedies from the arsenal of traditional medicine have proven themselves well. At the same time, however, it should be remembered that such methods cannot increase the secretion of lacrimal fluid and are not able to heal organic eye defects. The remedies offered by traditional medicine have an antiseptic and metabolic effect on the epithelium of the eye, relieving symptoms and discomfort. Therefore, they can be used in parallel, but not instead of traditional drug treatment.

The most popular remedy to help get rid of the feeling of “sand” in the eyes is washing with decoctions of sage, chamomile and calendula. They are prepared in a water bath, at the rate of a tablespoon of raw materials for one glass of boiling water.

You can also prepare a tincture of sheepskin. To do this, mix one tablespoon of herbs with a glass of water, bring the mixture to a boil. The broth is filtered and eye baths are made.

Honey drops have proven themselves well. They are prepared by mixing a teaspoon of honey (only natural honey can be used) with 500 ml of distilled water. The honey should completely dissolve. The tool is used twice a day, one drop in each eye. Store the finished composition in the refrigerator.

Prevention of xerophthalmia

As you know, preventing a disease is always much easier than treating it later. Xerophthalmia is no exception. According to statistics, there are a number of factors that contribute to the development of this problem. So, the eyes dry up with increased eye strain, prolonged work at the computer and reading; as a result of low air humidity; in conditions of high ambient temperature; in the presence of constant directed air flows, for example, from a fan or air conditioner; due to irritants (toxins, allergens, dust).

In order not to disturb the balance between the secretion of tear fluid and its evaporation, you should limit the time spent at the computer, and also regularly, every thirty minutes, take breaks during which you close your eyes.

If the air conditioner or fan is running in the room, the air flow should not be directed towards the face.

When working in conditions of high air temperature, moisturizing drops – “artificial tears” should be used.

Xerophthalmia and contact lenses

Dry eyes are one of the most common reasons for not using contact lenses. Most often, when using lenses, patients complain of discomfort towards the end of the day, as well as when working at the monitor.

In the event that the use of contact lenses is associated with constant discomfort, you should discuss with your doctor the possibility of switching to another type of contact correction or changing the solution used to care for the lenses. In addition, the use of moisturizing drops may be recommended to reduce unpleasant symptoms.

It should be noted that many eye drops cannot be used while wearing contact lenses. As a rule, the existing restrictions are indicated in the instructions for the medicinal product. Also, eye ointments should not be used while using lenses.

What causes dry eyes

Dry eyes is a symptom that not only causes very significant discomfort, but can also cause serious complications. This is due to the development of the inflammatory process, which can lead to very serious consequences.

It should be borne in mind that with timely treatment, dry eye syndrome can be eliminated. If the patient ignores the manifestations of xerophthalmia for a long time, it can lead to inflammatory changes in the cornea and other tissues of the eye.

So, because of the dry eye syndrome, conjunctivitis (inflammatory processes in the conjunctiva) and keratitis (inflammation of the cornea) can occur. They are manifested by redness of the sclera and conjunctiva, sensation of a foreign body in the eyes, photophobia.

In especially severe cases, an expression may even appear on the cornea. Sometimes ulcers can be so deep that they penetrate the cornea through and through – in this case they speak of perforation. This is fraught with retinal detachment and complete blindness.