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We’ve heard that sitting and staring at a computer for hours on end is bad for our physical and mental well-being.
What we may not know is that it may also be harmful to our eyesight as well.
Experts call it digital eyestrain or computer vision syndrome. If you’ve ever experienced dry eyes, blurred vision, eye fatigue or head, neck and back pain when using a computer or other digital device, then you know what it is.
And you’re hardly alone. Nearly two out of three people have experienced eyestrain after prolonged use of electronic devices, according to the 2015 report “Hindsight is 20/20/20: Protect Your Eyes from Digital Devices,” from The Vision Council.
March is Workplace Eye Wellness Month, so we asked a local expert to focus on the topic.
Experts point out that eyestrain from computer use comes from several sources. The first is the light emanating from the screen. Computer monitors and other electronic devices emit HEV light—also called blue light—which may cause permanent damage to our eyes. HEV light is that portion of the visible light spectrum that comprises light with the shortest wavelengths, which carry the greatest potential to damage living tissue, especially retinal tissue.
“In macular degeneration the receptors for blue are the first to go,” says Robert Abel, M.D., of Delaware Ophthalmology Consultants in north Wilmington.
Remember when your mother warned you about sitting too close to the TV? Turns out mom may have had a point. Here’s why: Two sets of muscles work in tandem to view the screen. One set converges on the same point. The other set flexes the lens in each eye to focus the light onto the retina. As with any other muscle, prolonged flexing can lead to repetitive stress issues. Symptoms include blurred vision, inability to focus on the screen and headache.
Do your eyes ever feel scratchy or irritated after a long session at the computer? That feeling is a common symptom of dry eyes, a condition that occurs when we blink less frequently. Blinking is important because it spreads tears over the surface of the eye. A relatively normal blink rate is 12 to 15 blinks per minute, but researchers at Ohio State University have found that people reading a computer display blink half that much, which takes a toll on the eyes.
Little wonder that computer vision issues take the No. 1 spot on OSHA’s list of workplace-related health concerns. The National Eye Institute has also released data showing a 66 percent increase in the prevalence of myopia since the 25 years following the appearance of the personal computer.
It may sound cliché but we only get one set of eyes and they do an awful lot for us.
“I think the eye is the center of the body,” says Abel. “It certainly is the center of your sensory system. Eighty percent of our connection to the world comes through the eyes and 40 percent of all nerve fibers connected to the brain are linked to the retina.”
The good news is there are many ways to lessen the strain felt when viewing the computer. Here are some recommendations from the American Academy of Ophthalmology:
1. Keep your distance. The eyes have to work harder to see close up than far away. If you’re working at a desktop, try placing the monitor approximately 25 inches away from your face. You may need to adjust the type to appear larger at that distance.
2. Take care of glare. Reflections on your computer screen can also cause computer eyestrain. Consider installing an anti-glare screen on the monitor, covering windows and reducing the intensity of light surrounding the workstation. Position your desk lamp away from the monitor. If you wear glasses, consider purchasing lenses with an anti-reflective coating. If possible, turn off overhead fluorescent lighting or use a visor.
3. Give your eyes a time-out. Just as carpal tunnel syndrome can hurt your wrists, eyestrain can result from prolonged periods of reading hard copy or viewing digital screens up close. Follow the 20-20-20 rule: Take a break every 20 minutes by looking at an object 20 feet away for 20 seconds. Looking into the distance will give your eyes a chance to relax.
4. Defy dry eye. Modern office buildings have humidity-controlled environments that suck moisture from the air. Indoor heating and air conditioning can compound the problem. Remember to blink more often and keep artificial tears at hand to help lubricate eyes. Consider purchasing a desktop humidifier to add localized moisture. This is especially important for soft contact lens wearers.
5. Dial down the color temperature. This is a technical term that refers to the spectrum of visible light emitted by a color display. Reducing the color temperature of the display lowers the amount of blue light for better—and safer—long-term viewing comfort. If you wear glasses, consider purchasing lenses, which filter out dangerous blue light from reaching your eyes or consider a pair of fit-over blocking glasses.
6. Get a comprehensive eye exam. The National Institute of Occupational Safety and Health (NIOSH) advises computer users to have an eye exam before they start working on a computer and once a year thereafter. Be sure to tell the doctor how much you use your computer and under what conditions.
“You don’t want to take anything for granted,” says Abel. “These two headlights you have do a lot of work for you and you and you never know if they’re overused until you’re 75 years old and realize you can’t read the street signs.”