Computer Vision Syndrome

Computers and electronic devices have become part of our lives. It’s not only with “mouse elbow,” wrist pain, and muscle tension that we see signs of this. Optometrists and ophthalmologists are seeing a collection of symptoms that they call computer vision syndrome (CVS) or sometimes digital eye strain. This constellation of symptoms includes tired eyes, dry eyes, irritation and/or burning, redness, blurred vision, possible double vision, and neck and back pain. Vision specialists estimate that about 75% of people who work at a computer screen have at least some of these symptoms.

CVS has been likened to other repetitive stress injuries—your eyes are following the same path over and over and over as you work at the computer. While we are working at the computer, our eyes constantly focus, refocus, in a repetitive way. This takes a lot of effort from the muscles that control our eyes. While even prolonged reading of a book can produce eye strain, the computer adds additional conditions. The computer and electronic devices add contrast, flicker, and glare to the repetitive eye movement experience.

Research studies have shown that we blink less when working at the computer—66% less, in fact. That leads to dry eyes, burning eyes, and tired eyes even without any other eye problem.Unfortunately, aging (over 40), and another vision dysfunction (astigmatism, etc.) make it more likely that you will develop CVS, so prevention becomes very important.

Simple things such as how your workstation is set up can help prevent CVS.

• Make sure that your monitor is positioned so that there are no reflections.
• Attention to good seated posture is important; you might find yourself in awkward positions if you try to avoid glare and reflections on your monitor.
• To avoid glare, you should not have windows directly in front of or behind the monitor. Overhead lights can also cause glare.  Rather than overhead lighting, use a lamp focused on the desk or keyboard or paper, but not on the monitor.
• Fluorescent lights have more blue light and that can increase strain. Simply changing the type of light can help reduce CVS. Try an LED light that’s labeled “sunlight.” There are also less “blue” options in the fluorescent light categories.
• The refresh rate of your monitor should be set at 70–85Hz.
• The position of the monitor is important. It’s usually suggested that the monitor should be 20 to 26 inches away. If that’s not possible, then glasses specifically for computer work may be the answer. These may make the difference in being seated ergonomically at the computer.

Blinking is important since that keeps the surface of the eye moist. A good first step toward prevention of dry eye is simply to be aware of the tendency not to blink often or to have only partial blinks. Using eye lubricants, and taking a “vision break” periodically will help prevent CVS.  The American Optometric Association recommends the 20-20-20 rule: for every 20 minutes of computer use, look at something at least 20 feet away for  20 seconds.