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Dry eye syndrome

Most computer users and people using contact lenses or working in an air-conditioned environment suffer from dry eye syndrome. It is a multifactorial disease of tears and the ocular surface. Common symptoms are dryness, soreness, scratchiness, eye irritation, blurred vision, burning and even dilated blood vessels (red eyes) at later stages. Reflex tearing, or the eyes "running water," is also common. Typically this is described as the eyes becoming "wet" but with rare spill over (so that the tears rarely run down the cheek). If untreated for a long period of time, it can even lead to eye damage. Dry eye syndrome affects 20% of the general population in Europe, North America and Asia [1].

Ed Jaccoma MD. explains it nicely. We all have two ways to make tears. The first is what we might call the "water sprinkler system". This constant production is coming from the many tiny glands lining the eyelids and is what normally keeps the eyes moist under most conditions. The second system is what we might call the "fire hose". This is the salty water that comes from the large tear glands responsible for the water we cry with when we get emotional, or when something gets into our eyes. While diagnosing dry eye, you may be found deficient in quantity and/or may be producing poor tear quality or have inflammatory properties that irritate your eyes.

Healthy people blink 10 to 15 times per minute. While working at computer, the majority of users blink considerably less. Blehm et al. [2] observe up to a 60% reduction in blink rate. We have observed even up to 80% (it varies from person to person). The reason for our low blink rate has to do with the brightness of computer screen. It is similar to flames: we blink significantly less while looking into the fire. With a low blink rate, the tear film is not renewed and our eyes get dry.

[1] Benitez-del-Castillo, J.M., Lemp, M.A., Ocular Surface Disorders. Jp Medical Pub 2012

[2] BLEHM, C. et al. Computer Vision Syndrome: A Review. Survey of Ophthalmology. 2005, Available online.


Blinking matters

With each blink the tear film is renewed. Tear film consists of three sublayers: mucus, watery layer and oil layer at the top, which protects the eye from dryness (water evaporation). Tear film is a microscopic layer which protects and moisturizes our eyes. It is similar to flowers; without water they dry out. We could also compare it to a car engine which ceases without oil. Blinking matters! It washes out dust and microorganisms. Healthy people have a tear film layer 6 +/- 2.4 micrometers thick, compared to people with dry eye syndrome whose tears have a film of only 2 +/- 1.5 micrometers [3].

Each eye blink restores the tear film that protects our eyes.

Holland and Tarlow [4] say that blinking is related to cognitive processes. Blink rate is low during mental activities like solving arithmetic tasks or daydreaming. A blink occurs together with cognitive change. When solving arithmetic problems, we usually do not blink at all. As soon as we find the solution, we blink. Another example is reading. Most blinks occur at punctuation marks. In contrast, emotional excitement and frustration are related to a high blink rate. This is another reason to be careful; not only monitor brightness, but also mental tasks decrease our blink rate.

Environmental factors, such as air conditioning, fans, heating systems, low humidity, and dust, can also have a negative influence on the tear film quality. Contact lenses often reduce tear film quality. Some people do not fully close their eyes while blinking. As a result, their tear film is not fully renewed [5]. Optometrists and ophtalmologists often prescribe artificial tears. The problem is that artificial tears will never heal the disease; they just suppress the symptoms. The only way to recover from dry eye syndrome is to blink more. Eyeblink can help you with this.

[3] BRIGHTBILL, FS, McDONNELL, PJ, McGHEE, CH. Corneal Surgery: Theory Technique and Tissue. 4th edition, Pennsylvania: Mosby Elsevier, 2008.

[4] HOLLAND, M. K. – TARLOW, G. Blinking And Thinking. In Perceptual and Motor Skills, 1975, Available online.

[5] ROSENFIELD, M. Computer vision syndrome: a review of ocular causes and potential treatments. Ophthalmic and Physiological Optics. 2011, Available online.


Meibomian gland dysfunction

Completeness of the blink is even more important than blink rate. While comparing reading from hard copy and a computer screen, the blink rate does not differ significantly but the number of incomplete blinks increases [6, 7]. Cardona et al. present a study [8] of blink characteristics while playing video games compared to normal conditions. Blink rate can decrease to one-half of baseline levels with a raise in incomplete blinks while playing computer games.

[6] M. Argils, et al. Blink rate and incomplete blinks in six different controlled hard-copy and electronic reading conditions blink rate and incomplete blinks, Investigative Ophthalmology and Visual Science, 2015, Available online.

[7] C. A. Chu, et al. Blink patterns: Reading from a computer screen versus hard copy. Optometry and Vision Science, 2014, Available online.

[8] G. Cardona, et al. Blink rate, blink amplitude, and tear film integrity during dynamic visual display terminal tasks. Current Eye Research, 2011, Available online.

Why blink completeness matters?

The lipid layer consists of meibum produced by Meibomian glands and it is spread on the eye surface during the complete blink only. Meibomian glands are placed at the rim of eyelids inside the tarsal plate. During eye blink, eyelids need to touch, so the meibum can be spread over the ocular surface to protect it from evaporation. Due to incomplete blinks, the meibum stays in glands. The gland orifices are blocked with clusters of keratotic cells due to which Meibomian glands are not functioning well and the lipid layer is not renewed properly. This state is referred as Meibomian Gland Dysfunction (MGD) [9]. Obstructive MGD is now recognized as the most common cause of the evaporative dry eye.

[9] D. R. Korb, et al. Tear film lipid layer thickness as a function of blinking. Cornea, 1994, Available online.


What are the possibilities to treat dry eye?

Light conditions are important aspect of eye care. Proper settings during day or night make it more comfortable for our eyes while working at a computer.

The best way to avoid dry eye syndrome is to blink properly. That is why Eyeblink should accompany you while working with computer. There are several other recommendations that can help you fight this disease. A warm eyelid massage delivers temporary relief from soreness. Just moisturize a handkerchief with warm water, put it on your eyes and massage. Focusing for long periods of time on objects at a close distance can be accompanied by headaches. Taking breaks and washing the eyes with cold water several times a day works great. After completing a small task, stand up from your computer, make a cup of tea or just look out the window. Taking small breaks (away from PC) after finishing a task will become automatic (like a reward). The 20/20/20 rule is very effective. After 20 minutes of work at computer, you should look at an object 20ft (6 meters) away for about 20 seconds. Taking small breaks is vital for maintaining eye health. Based on our observations (we recorded many people while working on our eye blink detection algorithm) people very often blink when they change their focus and look away from the computer screen.

Working environment is important; when possible, opt for matte screens. The screen should be 20 inches (0.5 meter) away from your eyes and at a 10-20 degree angle as illustrated in the picture. Light conditions are important - you should always adjust the brightness of your screen to be comfortable for your eyes (as eyeblink does). Natural light should come from the side; the window should not be behind or in front of the computer screen because of the contrast in lighting during midday or at night. During late hours, a room light or small lamp placed behind the screen will help to make lighting conditions more comfortable for our eyes.

Homemade treatment for dry eye and MGD

EyeThera provides a complex home treatment for dry eye. It contains HydroEye Daily Supplement (vitamins), Oasis Preservative-Free tears, cleanser, towelettes and mostly Bruder moist heat eye Compresses mask. The whole treatment intends to reset your Meibomian glands, mainly the mask helps to unblock clusters of keratotic cells from Meibomian glands to release the meibum. In the morning, heat the mask and wear it for 5 minutes. Then, the Avenova spray (a disinfectant) is used to kill germs. After, use the Cliradex towelettes to wipe out the dead germs. They are a tea tree oil derivative that acts as a skin cleanser and are inhibitory to the growth of bacteria, fungi and mold (but not a disinfectant). Because the goal is to kill germs that live on the oils and proteins in our tears and then procreate on our lids and lashes, it is helpful to use both methods. Use 2 capsules of HydroEye daily supplement in the morning and the other 2 in the evening. During the day use the refrigerated Oasis tears 4-6 times. Drink plenty of water. In the winter, use a humidifier. In the summer, avoid sitting near fans and air conditioners. In the evening use again the Bruder moist heat eye Compresses mask for 5 minutes and Avenova spray to disinfect your eyelids.

Which artificial tears are the best?

Based on our personal experience, we do not recommend long lasting use of any artificial tears because your eyes will get used to it. If external tears are provided, the eyes will not be forced to produce enough of their own tears. Our own tears are normally much better than any artificial ones. Care about your eyes and instead of eye drops wash them often with cold water. Eye drops can help you in the short-term. If you want to use any eye drops, use preservative-free ones and small capsules to minimize the risk of infection, e.g. Oasis tears.

Blinking exercise

When you suffer from incomplete blinks, it is important to exercise blinking. Close your eyes for 5 seconds and open them. While your eyes are closed, alse try to squeeze, put more pressure on Meibomian glands. Repeat it 5x in a row.