In this day and age, computers, smart phones and similar technologies are everywhere. Many hours are spent by most of us, either during our leisure time or for work, looking at the lighted screen of a computer or smart phone. As our eye doctor can explain during your next eye exam, this often leads to a group of eye and vision-related disorders commonly referred to as Computer Vision Syndrome.
Symptoms of Computer Vision Syndrome
As much as 90 percent of all people who consistently work with computers suffer from eye strain and other symptoms associated with Computer Vision Syndrome. The most common symptoms associated with Computer Vision Syndrome (CVS) are:
- blurred vision
- dry eyes
- neck and shoulder pain
A number of causes may lead to these symptoms, including:
- poor lighting
- glare on the computer screen
- improper viewing distances
- poor seating posture
- uncorrected vision problems
- a combination of these factors
Fortunately, many of these symptoms are temporary and tend to fade as soon as the person leaves the computer for a significant amount of time. However, there are instances in which individuals do experience reduced visual abilities, such as blurred distance vision, even though they have stopped working at their computer. In this case, symptoms may continue to recur and even worsen with future computer use if steps are not taken to address the issue.
Fortunately, there are many steps one can take to reduce his/her risk of computer eye strain and other common symptoms of computer vision syndrome. These include changing your monitor settings to accommodate your vision more comfortably, performing certain eye exercises to keep your eyes from straining and changing your work set up to reduce glare and uncomfortable lighting conditions.
Causes of Computer Vision Syndrome
At greatest risk for developing CVS are those persons who spend two or more continuous hours at a computer every day. The eyes tend to have to work harder when viewing a computer screen, making many individuals susceptible to the development of eye and vision-related symptoms.
Letters on the computer screen are often not as precise or sharply defined as they are on a printed page, and the level of contrast of the letters to the background is also generally reduced, making letters harder to discern.
Viewing distances and angles used for computer work are also often different from those commonly used for other reading or writing tasks. As a result, the eye focusing and eye movement requirements for computer viewing can place additional demands on the visual system.
Vision problems like farsightedness and astigmatism that have gone untreated tend to make symptoms worse, as do inadequate eye focusing or eye coordination abilities, and changes in the eyes as a consequence of aging, such as presbyopia.
Even those with a proper eyeglass or contact lens prescription may find specific viewing distances of their computer screen uncomfortable. This causes some people to tilt their heads at odd angles or bend toward the screen because their glasses aren’t designed for some of the difficulties of computer viewing. Poor posture often results, and can cause muscle spasms or pain in the neck, shoulder or back.
Diagnosis of Computer Vision Syndrome
Usually a comprehensive eye examination is enough to identify symptoms of CVS. Testing, with special emphasis on visual requirements at the computer working distance, may include:
- Patient history to identify symptoms and the presence of any general health problems, medications being taken, or environmental factors that may contribute to computer related symptoms.
- Visual acuity measurements to assess the extent to which vision may be affected.
- A refraction to determine appropriate lens power to compensate for refractive errors such as nearsightedness, farsightedness or astigmatism.
- Testing how the eyes focus, move and work together. In order to obtain a clear, single image of what is being viewed, the eyes must effectively change focus, move and work in unison. This testing will look for problems that keep your eyes from focusing effectively or make it difficult to use both eyes together.
- Using the information obtained from these tests, along with results of other tests, your optometrist can determine if you have Computer Vision Syndrome and advise you on treatment options.
Eye Care When Using The Computer
Even individuals who do not require eyeglasses or contacts for other daily activities can benefit from specially designed “computer glasses,” prescribed specifically for computer use. Persons already wearing glasses may find their current prescription does not provide optimal vision for viewing a computer, and may also consider computer glasses.
Some computer users experience problems with eye focusing or eye coordination that can’t be adequately corrected with eyeglasses or contact lenses. A program of vision therapy may be needed to treat these specific problems. Vision therapy, also called visual training, is a structured program of visual activities prescribed to improve visual abilities. It trains the eyes and brain to work together more effectively. These eye exercises help remediate deficiencies in eye movement, eye focusing and eye teaming and reinforce the eye-brain connection. Treatment may include office-based as well as home training procedures.
How You Should Be Viewing Your Computer
Some important factors in preventing or reducing the symptoms of CVS have to do with the computer and how it is used. The following are a few factors to consider:
Location of computer screen
Most people find it more comfortable to view a computer when the eyes are looking downward. Optimally, the computer screen should be 15 to 20 degrees below eye level (about 4 or 5 inches) as measured from the center of the screen and 20 to 28 inches from the eyes.
These materials should be located above the keyboard and below the monitor. If this is not possible, a document holder can be used beside the monitor. The goal is to position the documents so you do not need to move your head to look from the document to the screen.
Lighting at the computer
Position the computer screen to avoid glare, particularly from overhead lighting or windows. Use blinds or drapes on windows and replace the light bulbs in desk lamps with bulbs of lower wattage.
If there is no way to minimize glare from light sources, consider using a screen glare filter. These filters decrease the amount of light reflected from the screen.
Chairs should be comfortably padded and conform to the body. Chair height should be adjusted so your feet rest flat on the floor. If your chair has arms, they should be adjusted to provide arm support while you are typing. Your wrists shouldn’t rest on the keyboard when typing.
To prevent eyestrain, try to rest your eyes when using the computer for long periods. Rest your eyes for 15 minutes after two hours of continuous computer use. Also, for every 20 minutes of computer viewing, look into the distance for 20 seconds to allow your eyes a chance to refocus.
Blinking when using the computer
To minimize your chances of developing dry eye when using a computer, make an effort to blink frequently. Blinking keeps the front surface of your eye moist.
Regular eye examinations at our Toronto eye clinic and proper viewing habits can help to prevent or reduce the development of the symptoms associated with Computer Vision Syndrome.