Computers and Your Eyes: Bringing CVS into Focus
Each year, the number of people using a computer grows exponentially. Many people spend hours on the computer for various reasons ranging from work to school to recreation. Unfortunately, this can lead to an acute form of eye fatigue commonly known as computer vision syndrome, or CVS. For many people, CVS is characterized by red, watery, and irritated eyes. Some also experience headaches, difficulty focusing, blurry vision, fatigue and a general sense that “something just isn’t right” while gazing at a computer screen.
It’s estimated that two-thirds of the world’s population suffer from eye fatigue related to computer use. According to the American Optometric Association, about 14% of people who schedule eye exams do so because of CVS. This condition causes excessive eye strain and often leads to a significant decline in accuracy and productivity while working on a computer. Only your licensed eye care provider can assess whether or not CVS is affecting you.
What is CVS?
Unlike a conventional photograph or painting, a computer image is actually made up of tiny dots, or pixels rather than a solid image, and these dots flicker on-and-off depending on what’s called the refresh rate of the monitor. The result is that your eyes must constantly focus and refocus in order to keep the image sharp which, in turn, leads to eye strain. To make things worse, people using a computer for long periods of time tend to blink less frequently, creating dry patches on the front surface of the eye. This combination of difficulty focusing and eye dryness, dramatically increases fatigue and decreases productivity.
Treatments for CVS.
To relieve the symptoms of CVS including burning, tearing, or a gritty sensation, artificial tears are often recommended. Talk to your licensed eye care provider for specifics on eye drops to use and treatment schedules.
One important factor affecting CVS is ergonomics. Ergonomics refers to the body’s physical interaction with its work environment. This includes lighting conditions, seating, posture, and the position of the computer display relative to the user. Adjusting these variables properly can reduce the amount of eye fatigue and eye strain due to CVS. Optimally, the computer monitor should be placed approximately five or six inches below eye level measured from the center of the monitor and 20 to 28 inches away from the eyes, which typically falls in the intermediate zone of vision.
Perhaps the most important factor for many computer users is their eyeglass prescription. For people under 40 who wear glasses, chances are their lenses only correct for distance vision; for people over 40 who wear bifocals, their lenses only correct for near and distance vision. Most conventional trifocals and progressive lenses, or no-line bifocals, dedicate only a small portion of the lens to the intermediate zone of vision, and are therefore not optimized for comfortable computer use. This is why many computer users are now asking for lenses designed specifically for vision in the intermediate zone; these glasses are commonly referred to as “computer glasses”. Only your licensed eye care provider can prescribe these specialized lenses for you.
The simplest kind of computer glasses are single vision glasses which have a modified lens power ideal for reading a computer monitor. This lens allows the eyes to minimize the accommodation needed to focus on images in the intermediate zone. Another popular type of computer eyeglasses are occupational progressive lenses, which emphasize the intermediate and near zones of vision with a small portion reserved for distance vision. This reduces the need to adjust the neck or head often experienced by those who wear conventional progressive lenses while working on a computer. An anti-reflective coating should also be included on any lens designed for computer use to reduce the amount of glare from the computer screen which can also contribute to CVS symptoms.
If you use a computer often, be sure to discuss CVS with your eye care provider at your next annual eye exam. Computer glasses can often be the simplest and most effective way to maximize accuracy and productivity, while minimizing the symptoms of computer vision syndrome. Remember, many people are experiencing the effects of CVS and are barely aware of it, so schedule an annual eye exam with your eye care provider today.