What is dry eye?
Dry eye occurs when the eye does not produce tears properly, or when the tears are not of the correct consistency and evaporate too quickly.
In addition, inflammation of the surface of the eye may occur along with dry eye. If left untreated, this condition can lead to pain, ulcers, or scars on the cornea, and some loss of vision. However, permanent loss of vision from dry eye is uncommon.
Dry eye can make it more difficult to perform some activities, such as using a computer or reading for an extended period of time, and it can decrease tolerance for dry environments, such as the air inside an airplane.
What are the types of dry eye?
1) Aqueous tear-deficient dry eye is a disorder in which the lacrimal glands fail to produce enough of the watery component of tears to maintain a healthy eye surface.
2) Evaporative dry eye may result from inflammation of the meibomian glands, also located in the eyelids. These glands make the lipid or oily part of tears that slows evaporation and keeps the tears stable.
Dry eye can be associated with:
- inflammation of the surface of the eye, the lacrimal gland, or the conjunctiva;
- any disease process that alters the components of the tears;
- an increase in the surface of the eye, as in thyroid disease when the eye protrudes forward;
- cosmetic surgery, if the eyelids are opened too widely.
What are the symptoms of dry eye?
Dry eye symptoms may include any of the following:
- stinging or burning of the eye;
- a sandy or gritty feeling as if something is in the eye;
- episodes of excess tears following very dry eye periods;
- a stringy discharge from the eye;
- pain and redness of the eye;
- episodes of blurred vision;
- heavy eyelids;
- inability to cry when emotionally stressed;
- uncomfortable contact lenses;
- decreased tolerance of reading, working on the computer, or any activity that requires sustained visual attention;
- eye fatigue.
What are the causes of dry eye?
Dry eye can be a temporary or chronic condition:
- Dry eye can be a side effect of some medications, including antihistamines, nasal decongestants, tranquilizers, certain blood pressure medicines, Parkinson’s medications, birth control pills and anti-depressants.
- Skin disease on or around the eyelids can result in dry eye.
- Diseases of the glands in the eyelids, such as meibomian gland dysfunction, can cause dry eye.
- Dry eye can occur in women who are pregnant.
- Women who are on hormone replacement therapy may experience dry eye symptoms. Women taking only estrogen are 70 percent more likely to experience dry eye, whereas those taking estrogen and progesterone have a 30 percent increased risk of developing dry eye.
- Dry eye can also develop after the refractive surgery known as LASIK. These symptoms generally last three to six months, but may last longer in some cases.
- Dry eye can result from chemical and thermal burns that scar the membrane lining the eyelids and covering the eye.
- Allergies can be associated with dry eye.
- Infrequent blinking, associated with staring at computer or video screens, may also lead to dry eye symptoms.
- Both excessive and insufficient dosages of vitamins can contribute to dry eye.
- Homeopathic remedies may have an adverse impact on a dry eye condition.
- Loss of sensation in the cornea from long-term contact lens wear can lead to dry eye.
- Dry eye can be associated with immune system disorders such as Sjögren’s syndrome, lupus, and rheumatoid arthritis. Sjögren’s leads to inflammation and dryness of the mouth, eyes, and other mucous membranes. It can also affect other organs, including the kidneys, lungs and blood vessels.
- Dry eye can be a symptom of chronic inflammation of the conjunctiva, the membrane lining the eyelid and covering the front part of the eye, or the lacrimal gland. Chronic conjunctivitis can be caused by certain eye diseases, infection, exposure to irritants such as chemical fumes and tobacco smoke, or drafts from air conditioning or heating.
- If the surface area of the eye is increased, as in thyroid disease when the eye protrudes forward or after cosmetic surgery if the eyelids are opened too widely, dry eye can result.
- Dry eye may occur from exposure keratitis, in which the eyelids do not close completely during sleep.
How is dry eye treated?
Dry eye conditions are treated in a step-wise approach, with a management plan tailored to each individual patient. To find out more about our dry eye clinic and our approach to treating dry eye, click here.
What can I do to help myself?
- Use artificial tears, gels, gel inserts, and ointments – available over the counter – as the first line of therapy. They offer temporary relief and provide an important replacement of naturally produced tears in patients with aqueous tear deficiency. Avoid artificial tears with preservatives if you need to apply them more than four times a day or preparations with chemicals that cause blood vessels to constrict.
- Wearing glasses or sunglasses that fit close to the face (wrap around shades) or that have side shields can help slow tear evaporation from the eye surfaces. Indoors, an air cleaner to filter dust and other particles helps prevent dry eyes. A humidifier also may help by adding moisture to the air.
- Avoid dry conditions and allow your eyes to rest when performing activities that require you to use your eyes for long periods of time. Instill lubricating eye drops while performing these tasks.