Tuesday, May 24, 2011

What is Computer Vision Syndrome - Symptoms & Prevention

What is computer vision syndrome ?

Computer vision syndrome (CVS) is a temporary condition resulting from focusing the eyes on a computer display for protracted, uninterrupted periods of time. Some symptoms of CVS include headaches, blurred vision, neck pain, redness in the eyes, fatigue, eye strain, dry, irritated eyes, double vision, polyopia, and difficulty refocusing the eyes. These symptoms can be further aggravated by improper lighting conditions (ie. bright overhead lighting or glare) or air moving past the eyes (e.g. overhead vents, direct air from a fan).


According to the National Institute of Occupational Safety and Health, computer vision syndrome affects some 90% of the people who spend three hours or more a day at a computer.


Dry eye is a major symptom that is targeted in the therapy of CVS. The use of over-the-counter artificial-tear solutions can reduce the effects of dry eye in CVS.

Asthenopic symptoms in the eye are responsible for much of the morbidity in CVS. Proper rest to the eye and its muscles is recommended to relieve the associated eye strain. Various catch-phrases have been used to spread awareness about giving rest to the eyes while working on computers. A routinely recommended approach is to consciously blink the eyes every now and then (this helps replenish the tear film) and to look out the window to a distant object or to the sky—doing so provides rest to the ciliary muscles. One of the catch phrases is the "20-20-20 rule": every 20 minutes, focus the eyes on an object 20 feet (6 meters) away for 20 seconds. This basically gives a convenient distance and timeframe for a person to follow the advice from the optometrist and ophthalmologist. Otherwise, the patient is advised to close his/her eyes (which has a similar effect) for 20 seconds, at least every half hour.

Decreased focusing capability is mitigated by wearing a small plus-powered (+1.00 to +1.50) over-the-counter pair of eyeglasses. Wearing these eyeglasses helps such patients regain their ability to focus on near objects. People who are engaged in other occupations—such as tailors engaged in embroidery—can experience similar symptoms and can be helped by these glasses.

Treatment for Computer Vision Syndrome

There are a number of over-the-counter eye drops you can buy to treat the symptom of dry eyes. But prevention is always better than cure.

As preventative measures you can do the following:

Follow The 10-10-10 Rule - When using a computer, look at an object 10 feet away, for 10 seconds, every 10 minutes. This relieves stress on the ciliary muscles and prevents the progression of myopia.

Blink More Often - Remember to consciously blink every now and then to replenish the tear film and prevent dry eyes.

Use Proper Lighting - Eye strain is often caused by extreme light contrast, such as excessively bright light from a window or the glare of a computer screen. Close drapes or blinds and reduce ambient lighting to lower levels.

Upgrade Your Computer Monitor - Modern LCD monitors are less likely to cause Computer Vision Syndrome than the old bulky CRT monitors. They have anti-reflective surfaces and a higher refresh rate so you don't have any flicker. Choose a screen size of at least 19 inches.

Relax with an Eye Mask - Give your eyes a rest after a long day at the computer screen. Wear a therapeutic eye mask that can be cooled or heated for fast and effective relief of eye strain, headaches and muscle tension.

Do Eye Exercises - If you are already suffering from blurry vision and worry about further vision deterioration, I recommend daily eye exercises for a set number of weeks. They can help strengthen and relax the eye muscles, which can increase your natural flexibility and focus.

What Are the Symptoms of Computer Vision Syndrome (CVS)?

Following are some common symptoms that people suffering from of Computer Vision Syndrome (CVS) experience and how to prevent them.


Squinting is the natural reaction of the eyes to the glare of the computer screen from fluorescent lights, direct sunlight from a window, or even from too much contrast between the displayed text on a screen and its background (intersights). Squinting is a primary cause of headaches, but headaches and pain in the forehead can also be attributed to the annoyance of looking at fuzzy-edged pixels on a computer screen.

The problem with staring at fuzzy pixels can be solved by purchasing a pair of glasses specifically designed to help your eyes focus on the unevenness of the pixels. These glasses can also be tinted to reduce the glare of the computer screen (eye2eye). Computer screen covers can also be purchased to reduce the glare of the screen.

Neck Pain

Neck pain can be caused in two ways. Eye glasses only use a small part of their lenses for the focusing of intermediate ranges. The neck and shoulders constantly move in an effort to view the screen clearly through this tiny part of the lenses, so the glasses that the person is wearing are the main contributors of the problem. If the person is not wearing eye glasses, then the pain is usually from the neck trying to compensate for the eye muscles being fatigued (intersights).

The neck will become sore when it's trying to compensate for tired eyes. Simply taking short breaks from the computer screen when the eyes begin to feel tired can this (intersights). If the person experiencing the neck pain is wearing multi-focal lens glasses, then merely useing a pair of single-vision glasses when working at a computer should get rid of the pain (intersights).

Burning Eyes

The longer a person looks at a computer screen, the more tired their eyes become, and the less that person blinks. Blinking is essential to maintaining a layer of water over the eyes. When blinking slows down, the eyes become drier which leads to the burning sensation (intersights).

Keeping the eyes from becoming tired will keep them from becoming dry. Preventing eye fatigue is done by simply taking short breaks from the computer screen when the eyes begin to feel tired. This will keep the eyes blinking at a normal rate and the layer of water on them will be maintained.

Double Vision

Eye muscles cramp up because people tend to stare at the computer screen as a result of fuzzy-edged pixels. When the muscles that control your eyes cramp up, double or blurred vision occurs. When a person looks up from their computer, their cramped eye muscles will cause blurred or double vision (intersights).

Glasses that are designed to prevent squinting at pixels may. Whenever the eyes get tired, a break of a few minutes from the computer screen is usually enough to get rid of the symptoms (eye2eye).