Dry eye disease or syndrome is usually caused either by an insufficient production of tears, or its increased evaporation. The condition causes irritation or produces a gritty sensation in the eyes. If not treated promptly, it can cause corneal infections and scarring.
Dry eye syndrome, which is also known as ‘keratoconjunctivitis sicca’, is a condition characterized by the dryness of the eyes, that usually results either from a decreased production of tears by the tear glands, or an increased evaporation of the tear film. The increased evaporation of tear can be caused by the abnormalities in its composition.
Due to an increased evaporation of the tear film, the amount of water in the film decreases, while the concentration of salt increases, which further dries the eyes by drawing out more water from the surface. This produces the characteristic sandy-gritty sensation or eye irritation, that is commonly associated with this eye disease.
The tear film consists of three layers – the outer oil layer, middle aqueous layer, and the base mucus layer. The outer layer is produced by the oil glands, and it provides a protective coating to the eye. This layer helps slow down the evaporation of tears. On the other hand, the middle aqueous layer keeps the eyes clean by removing dirt and debris, and also performs the vital functions of providing oxygen and nutrients to the eyes. The third mucus layer is mainly responsible for lubricating the eyes.
Causes
Several factors can be responsible for reducing the production of tears, and increasing its evaporation. The amount of tears in the eyes can reduce due to an inability of the lachrymal glands to produce sufficient tears. This in turn, can be caused by various factors, like aging, genetics, lacrimal ablation, and diseases like rheumatoid arthritis, Wegener’s granulomatosis, systemic lupus erythematosus, and Sjögren’s syndrome, etc.
Certain medications like diuretics, sedatives, antihistamines, beta blockers, contraceptives, and antidepressants can aggravate this condition. On the other hand, the rapid evaporation of the tear film can be caused due to an abnormal composition of tear. Factors like low humidity, use of contact lenses, and the presence of eye irritants like smoke or dry wind, can also cause this condition at times.
However, if it remains untreated, it can cause chronic dry eyes, which can lead to eye inflammation, infection of the cornea, and scarring. Some other factors that can cause this eye problem are, an injury to the eye, LASIK and refractive surgeries that involve the removal of the corneal nerves, blepharitis, and rosacea.
Signs and Symptoms
Persistent dryness, burning, itchiness, a sandy-gritty sensation in the eyes, and excessive tearing are the common symptoms of this condition. However, the excess tear secreted in this condition are watery, and so, it cannot maintain the level of moisture required for lubrication. Some other symptoms of this condition are, pain and redness of the eyes.
Treatment
Physicians usually perform several diagnostic tests to confirm the disease. The various treatment options available for this condition are either aimed at stimulating tear production or at tear retention. Some of these treatment options are, artificial tears, autologous serum eye drops, and eye ointments.
Punctal plugs can also be inserted into the puncta, the small opening in the eye that drains tears into the tear duct. The insertion of these plugs can block the drainage of tears to the nose, so that the eyes are left with more tears.
Cauterization is another treatment option which is usually performed, if the insertion of punctal plugs proves effective in retaining tears in the eyes. Here, the tear ducts are closed by destroying the tissues of the drainage area. Sometimes, surgery may also be required to treat this condition.
Dry eye syndrome can’t be prevented. But appropriate treatment can help manage this condition. Along with treatment, it is equally important to avoid irritants like smoke and dust, increase the consumption of foods that contain omega-3 fatty acids, and take proper eye care, in order to manage this condition effectively.
Disclaimer: This article is for informative purposes only, and should not be treated as a substitute for professional medical advice.