Preventing computer vision syndrome

By Dr Monda Ang’awa

For many of us, our eyes and the computer have an intimate relationship, spending countless hours together every day. With this has come an occupational hazard, the Computer Vision Syndrome (CVS), a group of eye problems caused by prolonged and repeated computer use — blurred vision, redness, burning, excessive tearing and itching, eye strain and fatigue, dry eye, light sensitivity, frequent headaches and frequent changes in eyeglass prescription. It is the result of our eyes getting stressed from spending too much time looking at the same thing and doing the same task day in and day out. The level of discomfort increases with the amount of computer use. It does not cause permanent eye damage, but reduces productivity and causes lost work time.

Here are some simple solutions to prevent or relieve CVS:

Computer eyewear

Get customised prescription glasses for your computer work especially if you usually wear contact lenses that may become dry and uncomfortable during sustained computer work.

Proper lighting

When using a computer, your ambient lighting should be about half that found in most offices. Closing curtains or blinds should eliminate sunlight. Reduce interior light by using fewer bulbs or lower intensity sources of light. Windows should be to the side of the monitor, not the front or back.

Minimise glare

Computer screens should have an anti-glare screen or a computer hood. The monitor should be cleaned frequently to remove dust that can contribute to glare. Walls should be painted a matte finish. Your spectacles should have lenses with an anti-reflective coat.

Liquid crystal display screens

These are easier on the eyes because they do not flicker, the contrast is higher and they have an anti-reflective surface.

Brightness and contrast

These should be about the same as your work environment and the contrast between the screen background and the on-screen characters high. Your text size should be three times the smallest text size you can read from your normal viewing position. Black text on a white background is the best colour combination for your eyes or other high-contrast, dark-on-light combinations.

Blinking

The eye normally blinks 10-15 times every minute spreading tears evenly on the eyeball surface keeping it moist and lubricated. The rate of blinking decreases by almost half when using the computer and the tears coating the eye evaporate faster during these long non-blinking phases causing itching and dryness.

Try blinking as often as you can or using artificial tears when using the computer to help rewet your eyes

Exercise your eyes

Eyestrain, blurred vision, headaches and difficulty changing focus occur when your eyes are tired.

Relax eye muscles by looking at a distant object for 10-15 seconds, then gaze at something up close for 10-15 seconds, then look back at the distant object. Do this 10 times. Also, take frequent breaks.

Your workstation

A poorly located computer screen causes awkward body positions. Position your computer screen two feet from your eyes with the centre of your screen four to nine inches below your eyes, because your eyes work best with a slight downward gaze the way you would hold a book for comfortable positioning of your head and neck. Place written pages on a well-lit copy stand adjacent to the monitor.