Dry eye is one of the most common eye disorder reported by the patients when they see their eyecare practitioner. Dry eye can affect patients in different severity, ranges from mild irritation to sight threatening scarring. Indeed, the classification of dry eye is more complicated than you think. Instead of trying to self-treat the dry eye problem by buying artificial tears over the counter, let’s take a deeper look into the dry eye syndrome first.
Dry Eye Questionnaire
Before we start, let’s fill in the dry eye questionnaire to briefly assess your dry eye condition. The questionnaire is simple yet effective to grade dry eye severity and it is very useful to monitor the dry eye treatment efficiency. You are probably suffer from symptomatic dry eye if you score 6 marks or more in the questionnaire.
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Dry Eye Classifications
According to the American Optometric Association, dry eye patients can be divided into either producing inadequate tears, namely aqueous deficient dry eye, or the tears evaporate too fast, namely evaporative dry eye. These two kinds of dry eye have different causes. Optometrists can conduct various assessments during eye exams to confirm the category of your dry eye problem.
Aqueous deficient dry eye
Aqueous deficient dry eye is the most common dry eye cause. According to the US National Eye Institute, normal aging decreases tears secretion and dry eye is more common in people over age 50 years. At the same time, women are more likely to develop dry eye due to hormonal changes. Besides aging, there are a wide range of medications which will limit tears production as side effect, such as drugs for anti-allergy, antidepressants and even birth control pills. On the other hand, autoimmune disease can cause inflammation of the lacrimal gland and reduces tears secretion. LASIK surgery will also reduce reflex tears and cause dry eye.
Evaporative dry eye
For evaporative dry eye, part of them are resulted from environmental factor. For example, windy, hot and dry environment increases tears evaporation. Smoking affects the tear quality, let the tears become more prone to evaporation. Also, the blinking rate can be slowed down by 4 times when people are concentrating on reading and using computer. Tears are easier to be evaporated between blinking and cause dryness. Moreover, eyelid inflammation and blockage of the oily glands on the lid, even being subtle, will also disrupt the oily layer of the tears and speed up tears evaporation. Other reasons of evaporative dry eye include contact lens deposits, preservatives from eyedrops and contact lens solutions, and eyelid anomalies which expose too much of the eyeball.
Dry Eye Consequences
Mild dry eye usually only causes discomfort and do not threaten vision. However, when the dry eye develops to a certain extent, the ocular surface will be damaged and start to affect the vision. In advanced cases, it can lead to corneal inflammation and infection which can cause blindness.
Easy-to-do Treatment Options of Dry Eye
In order to completely treat the dry eye disorder, we need to remove all of the underlying causes. However, it is not easy to find out all of them. Even so, you still cannot get rid of some dry eye causes, for example, aging. Therefore, some patients and even practitioners tend to just use artificial tears to cope with dry eye discomfort. But actually you can do more to further improve your dry eye condition. Below lists some of the easy-to-do options to tackle dry eye in general.
- Artificial Tears
It is true that artificial tears can alleviate the dryness sensation for most of the mild dry eye cases, especially in aqueous deficient cases. However, it is better to use artificial tears that are unidose, preservative free and without any additives and medications. Artificial tears are also available in different thickness and even in ointment form for overnight use. Your optometrist can give you better idea of the kind of artificial tears that suit you. - Lifestyle and environmental modification
Changing the visual habit, lifestyle and the living environment can improve evaporative dry eye conditions. For the visual habit, you should take at least 20 seconds of rest by looking at objects 20 feets or further on every 20 minutes of near work. Also, you should keep the working distance not closer than 35-40cm, allow enough lighting at appropriate angle and remind yourself to blink more during work. Correcting refractive error and binocular vision anomalies reduce fatigue and relieve dry eye sensation. Quit smoking, adjust the angle of air conditioning and use humidifier to slow down the evaporation of tears. - Lid hygiene and hot compress
Bacteria at the lid margin will break down the oily layer of the tears. But it is difficult to clean the lid margin by just washing the face. To improve the lid hygiene, you can fill in a bottle cap with water and then add a drop of baby shampoo. Then use a cotton bud to stir the solution and gently scrub your lid margin. This can also be done by commercially available lid scrubs. To free the blocked oily gland on the lid margin, you can use clean hot towel or eye mask at 40 degree Celcius. Close your eyes, place it on your lid and gently apply pressure on lid margin for 8-10 minutes. - Review your contact lenses
Contact lenses with high water content tend to compete water with your eye and worsen dry eye problem. At the same time, contact lenses that dispose less frequently have more deposits coat on the surface. These deposits reduce the wetting of the contact lens and elicit allergic inflammation, both contribute to dry eye problem. Some patients are allergic to contact lens solution preservatives and will also cause dry eye. Therefore, you should attend regular contact lens aftercare and let your optometrist to do necessary modifications. - Dry eye nutrition supplement
Researchers show omega-3 fatty acids supplement can regulate ocular inflammation and reduce dry eye severity. Natural omega-3 fatty acids food sources are cold water fish and flaxseed oil. Oral omega-3 fatty acids supplement, for example fish oil, can also act as dry eye supplement to reduce dry eye discomfort. Besides omega-3 fatty acids, some researches also reported the antioxidation property of blueberry can inhibit inflammation and reduce dry eye severity. However, currently there is still no official recommendations on the suggested dosage of omega-3 fatty acid or blueberry consumption for dry eye.
The cause and severity of dry eye disorder varies a lot. In order to better diagnose your situation, remember to seek expertise of your optometrist and do regular comprehensive eye exam.
By Jeff Tang, Registered (Part I) Optometrist
Eyecare information by Swisscoat Vision Centre
Address : G/F Yuen Yick Building, 27-29 Wellington Street, Central, Hong Kong
Appointment :+852 3579 4763
Website : www.swisscoat.com
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