There is itching, a burning sensation, irritation or grittiness, redness, blurred vision which improves with blinking, excessive tearing or increased discomfort after reading, watching TV or working at a computer.
Not only are the complaints numerous but the men, women and children who come to seek help are also worried because it concerns one of the most precious organs - the eye.
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| Pic courtesy doctormyeyes.net |
Dry eye is the cause, says Consultant Ophthalmologist Dr. Charith Fonseka who is attached to the Eye Hospital in Colombo, explaining that "dry eye syndrome" is extremely common now while 15 years ago it was not so.
"Dry eye syndrome is usually due to a problem with the quantity and/or quality of the tear film that lubricates the eyes," he says.
Why does it occur?
Excessive air movement dries out the eyes while other factors like hot, dry or windy climates, air-conditioning and cigarette smoke could also cause this syndrome. Contact lens wearers may also be prone, because contacts absorb the tear film, causing proteins to form on the surface of the lens, says Dr. Fonseka.
A simple measure that could be taken at home or in office against excessive air movement is to decrease the speed of ceiling or oscillating fans, advises Dr. Fonseka.
In highly urbanized areas there is much air pollution, MediScene understands, which lead to large amounts of dust and particulate matter being around us. "This particulate matter is due to the hydrocarbons including sulphur dioxide released into the air by vehicle emissions," he says, adding that these could be another cause.
How does Dry Eye Syndrome
come about?
It could result from decreased tear production, excessive tear evaporation or an abnormality in the production of mucus or lipids normally found in the tear-layer or a combination of all three, according to this eye specialist.
The normal aging process is one of the most common reasons for dryness, it is learnt. "As we grow older, our bodies produce less oil," he says pointing out that when a person is 65 years old, 60% less oil is produced than when he/she is 18. "This is more pronounced in women who tend to have drier skin than men."
The oil deficiency has a ripple effect…..without much oil to seal the watery layer, the tear film evaporates faster, leaving dry areas on the cornea.
Meibomian gland dysfunction can also lead to insufficient lipid layers, while if the oil glands are blocked or the oil is too thick, there may not be enough oil to cover the watery layer to prevent its evaporation.
Bacteria due to an infection, blepharitis, along the eyelids or eyelashes could also breakdown the oil which in turn may result in an inadequate quantity of oil being present.
Aqueous tear deficiency could be caused by either poor production -- due to age, hormonal changes or various autoimmune diseases such as primary Sjogren Syndrome, rheumatoid arthritis or lupus -- or excessive evaporation - due to an insufficient overlying lipid layer.
Some medications such as antihistamines, anti-depressants, beta-blockers and oral contraceptives may also decrease tear production, says Dr. Fonseka, while use of various eye-drops and glaucoma medication may be contributory factors. "If there is decreased blinking or if the eyelids cannot be closed, the eyes may dry out because of tear-evaporation.
When you read, watch TV, work at the computer or perform a task that requires close attention with the eyes you may not blink as you would normally do. This too leads to excessive evaporation of tears."
The third situation is when there is abnormal production of mucin by the conjunctiva which can result from chemical (alkali) burns of the eye or autoimmune diseases such as Stevens-Johnson Syndrome and cicatricial pemphigold, MediScene understands. Then there is poor spreading of tears over the eye surface which not only dries the eye but could also damage it, even though the eye has watery tears.
What of treatment?
Everyone's needs are a little different, says Dr. Fonseka, with many finding relief simply by using artificial tears regularly. Preservative-free tears are recommended as they are the most soothing and have fewer additives that could be potential irritants.
Artificial tears and lubricating eye-drops and gels, available over-the-counter provide more moisture and lubrication for the surface of the eye. What a person needs to use will depend on what provides the best relief to that person.
Lubricating eye ointments could also be used. As they are thicker than drops and gels, they may provide relief longer but could also blur the vision if used during the day. "That's why they are recommended for use overnight while you sleep," he says.
Another intervention could be closing the opening of the tear drain in the eyelid with special inserts called punctual plugs. Done on a temporary basis, with a dissolvable collagen plug or permanently with a silicon plug, it is like closing a sink drain with a stopper and traps the tears on the eye, he says.
Urging that it is important to treat dry eyes not only for comfort but also to maintain a healthy cornea, he says, hot compresses and eyelid scrubs/massages with baby shampoo help provide a thicker, more stable lipid layer. Used against meibomian gland dysfunction, rosacea or blepharitis, the heat from the compresses would warm up the oil in the glands, making it flow easily. "Massaging helps get the oil out of the glands and the cleaning process decreases the number of bacteria that breas kdown the oil."
Pointing out that simple lifestyle changes can significantly improve dry-eye irritation, Dr. Fonseka says drink eight to 10 glasses of water everyday to keep the body hydrated and flush out the impurities. Blink frequently, especially when reading or watching TV and avoid rubbing the eyes which would worsen the irritation.
If your eyes are dry mainly while watching TV or reading, take frequent breaks, suggests Dr. Fonseka, to allow your eyes to rest and become moist. And his advice: Close your eyes for 10 seconds every 5-10 minutes and also blink to improve eye comfort.
Those tears
Sometimes they flow when we are sad or happy and at other times when a speck goes into the eye.
Tears which are formed in several glands around the eye, are a vital component to keep our eyes healthy. They comprise three layers:
- The innermost mucus layer coats the cornea (the eye's clear outer window), forming a foundation so that the tear film can adhere to the eye. It is produced by small glands in the eye-lids.
- The middle aqueous layer provides moisture and supplies oxygen and other important nutrients to the cornea. It is made up of 98% water and a small amount of salt, proteins and other compounds. The aqueous or water layer is produced by the lacrimal gland under the upper eye-lid.
- The outer lipid layer is an oily film that seals the tear film on the eye and helps prevent evaporation. This layer, like the mucus layer, is produced by small meibomian glands in the eye-lids.
"When a person blinks, the eyelids spread the tears over the eye, with the excess tears flowing into two tiny drainage ducts in the corner of the eye, by the nose," says Dr. Fonseka. "These ducts lead to tiny canals that connect to the nasal passage."
Tears, in addition to lubricating the eye, are also produced as a reflex response to outside stimulus such as an injury or emotion, MediScene learns.
But, explains Dr. Fonseka, "reflex tears" do little to soothe a dry eye, pointing out that someone with "watery eyes" may still complain of irritation. |
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