Our eyes in the modern world

PHOTO: Our eyes in the modern world

On average, we spend more than three hours a day staring at the computer screen or some other electronic gadget.

I, myself, am guilty of this especially since I bought the latest MacBook Air I am writing this article on. You may well be reading this article on your computer or iPad.

This has led to the recognition amongst eye care professionals of a new syndrome called Computer Vision Syndrome (CVS). This is surprisingly common among the working population, but often untreated or mistaken for something else.

CVS is due to the eyes being used to focus on the computer screen for prolonged periods of time. Common symptoms include headaches, red eyes, blurred vision, neck pain, double vision, and dry and irritated eyes.

These symptoms may be aggravated by a smoky environment or air-conditioning vents blowing dry air in the direction of the person.

Eyes wide open

Most of us blink an average of 18 times per minute. This wipes away debris from the eye surface and keeps the eyes functioning optimally. However, when in front of computer screens, we blink less than six times per minute, which allows for dry, irritated eyes.

Our eyes are naturally developed to focus six metres (20 feet) in front, and if we look at a screen located less than a metre in front of us, we have to use our internal eye muscles to get the screen in focus. This can result in "eye-strain", which may be very uncomfortable for some people and difficult to resolve.

It is, of course, almost impossible for us to be separated from the computer as we not only need it for our work, but also for social networking.

The American Academy of Ophthalmology has recommended some simple steps to reduce CVS symptoms. These include:

  • Pasting a note on your screen to remind yourself to blink often.
  • Sitting at a comfortable position from the computer and position the screen so that your eye gaze is slightly downward.
  • Every 20 minutes, shift your eyes to look at an object at least 20 feet away, for at least 20 seconds: the "20-20-20" rule.
  • Taking regular breaks from computer work and getting enough sleep.

People with dry eyes are more likely to experience CVS. As such, artificial tear drops can help relieve eye discomfort. There are a huge variety of artificial tear drops available, and it would be best to discuss with an eye care professional the most suitable drop for yourself.

Most patients with dry eye also often have meibomian gland dysfunction (MGD) or blepharitis. MGD is very often unrecognised as a cause of eye discomfort.

The meibomian glands are located near our eye lashes and provide some of the lipid secretions that make up part of our tear film. In MGD, the glands are blocked and inflamed. This causes our eyes to feel gritty and sore, especially in the mornings.

A simple measure to treat MGD is to use a warm compress to massage the eyelids for about two minutes twice a day. The heat from the warm compress allows the sticky oily secretions from the glands to melt slightly. This can help relieve the blockage.

After the warm compresses, you can use a wet cotton bud to scrub the eyelashes to remove the oily secretions that have been released from the glands.

I tell my patients to do this whenever they brush their teeth so that they don't forget. This simple lid hygiene regimen has to be done daily for at least a month before improvement in symptoms can be seen. More severe cases of MGD may require steroid and antibiotic eye drops, and tetracycline antibiotic tablets.

 Supplement help

Supplement help

More recently, dietary supplements like omega-3 essential fatty acids (EFA) have been found to be useful for helping dry eye and MGD. Such essential fatty acids may help enhance the lipid layer of the tear film and prevent premature evaporation of the tears from our eyes.

Omega-3 EFAs also have an anti-inflammatory role in the eye. EFAs are called essential because they can't be produced in the body. There are two main groups: omega-3 and omega-6.

Omega-6 EFA is found in most vegetable oils like rapeseed, sunflower, peanut and corn, poultry, eggs, cereal, and whole grain breads. Omega-3 EFA, on the other hand, is found in oily fish (example: salmon, sardines, catfish, Indian mackerel, kembong or Spanish mackerel, tenggiri, jelawat, and canned tuna), and oils like flaxseed, rapeseed, and walnut.

Our modern diet has led to us taking an excess of omega-6 EFA, which limits the effectiveness of omega-3 EFA in helping dry eye and MGD. The ideal ratio of omega-3 to omega-6 EFA is 1:4, but most people in developed countries are taking a omega-3/omega-6 EFA ratio of up to 1:25!

In other words, we are taking more than 20 times the amount of omega-6 EFA compared with omega-3 EFA. A diet high in processed food and meat, and lacking in omega-3 fish oils causes this imbalanced ratio and can lead to higher incidence of dry eye.

Due to the difficulties at having enough omega-3 EFA in our diet, dietary supplementation of up to 500mg per day of omega-3 EFA is recommended by the American Dietetic Association.

Having said that, females who are pregnant or are breastfeeding should limit their intake of oily fish to two servings a week to avoid overconsumption of potential pollutants that may be found in the fish.

Several studies have found clear benefits of dietary supplements of omega-3 EFA for dry eye. Individuals taking these supplements had a 20 per cent reduction in the likelihood of getting dry eye compared with those with a low intake of omega-3 EFA.

New trials are now testing the use of omega-3 EFA as an eye drop for dry eye. In MGD, omega-3 EFA supplements help clear up and thin meibomian gland secretions which in turn improves dry eye symptoms.

Omega-3 EFAs have also been found to be beneficial for our heart (reduction in myocardial infarction), brain (reduced risk of stroke), and joints (helps reduce joint pain).

In summary, our eyes are not designed to look at the computer screen for hours each day. This can take a toll on our overall health, especially if we have co-existing dry eye and MGD.

The main suggestions that I have to prevent computer vision syndrome is to take regular breaks from your computer work, avoid a dry working environment, lid hygiene for MGD, consider artificial tear supplements, as well as increase omega-3 EFA intake.