Lt. Col. C. Kelly Olson, O.D.
Wiesbaden Army Health Clinic
How do you feel after spending a long day working at a computer? The average American worker spends seven hours a day on the computer either in the office or at home. According to the American Optometric Association, 58 percent of adults surveyed experience eye strain as a direct result of lengthy screen time.
March is Save Your Vision Month and the American Optometric Association is working to educate people about how to avoid computer vision syndrome in the workplace.
The most common symptoms associated with CVS are eyestrain, headaches, blurred vision, dry eyes and neck and shoulder pain. Many of the visual symptoms experienced by users are only temporary and will decline after stopping computer work or use of the digital device. However, some individuals may experience continued reduced visual abilities, such as blurred distance vision, even after stopping work at a computer. If nothing is done to address the cause of the problem, the symptoms will continue to recur and perhaps worsen.
What causes CVS?
Our eyes are most relaxed when looking at something in the distance. Viewing a computer makes the eyes work harder. Additionally, we tend to hold our eyes open wider and blink less frequently when looking at digital devices, which contributes to dry eye symptoms.
Viewing a computer or digital screen is different than reading a printed page. Often the letters on the computer or handheld device are not as precise or sharply defined, the level of contrast of the letters to the background is reduced, and the presence of glare and reflections on the screen may make viewing difficult.
Viewing distances and angles used for this type of 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 digital screen viewing can place additional demands on the visual system.
Even people who have an eyeglass or contact lens prescription may find that it’s not suitable for the specific viewing distances of their computer screen. Some people tilt their heads at odd angles because their glasses aren’t designed for looking at a computer. Or, they may bend toward the screen in order to see it clearly. Their postures can result in muscle pain in the neck, shoulder or back.
How is CVS treated?
Prevention or reduction of the vision problems associated with CVS involves taking steps to control lighting and glare on the device screen, establishing proper working distances and posture for screen viewing, and assuring that even minor vision problems are properly corrected.
To help alleviate digital eyestrain, follow the 20-20-20 rule; take a 20-second break to view something at least 20 feet away every 20 minutes.
Uncorrected vision problems like farsightedness and astigmatism, inadequate eye focusing or eye coordination abilities, and aging changes of the eyes, such as presbyopia, can all contribute to visual symptoms when using a computer or digital screen device.
Proper screen placement
Most people find it more comfortable to view a computer when their 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.
Some computer monitors have an “eye saver” feature to reduce brightness of the screen. If there is no way to minimize light sources, consider using a screen glare filter.