The scoop on sunglasses

UV rays can cause more than sunburns


— The thought of a summer sunburn makes most people reach for a bottle of sunscreen with a protective factor of at least 15. But how many of us shield our eyes from those same ultraviolet rays with equal zeal?

"Living in the mountains, because of the altitude and thinner atmosphere, we have less protection from ultraviolet rays," said Steamboat Springs optometrist Gary Migues. "Long-term, unprotected exposure can cause cataracts to develop at a quicker rate."

Migues defines a cataract as anything that affects the clarity of the optic lens inside the eye. Development of cataracts is generally related to age. People in their 40s or 50s who require reading glasses have already lost some flexibility and transparency in their optic lenses.

"Many factors are involved in the development of cataracts, including genetic predisposition," Migues said. "Normal, age-related cataracts that would become significant at age 65 or so might show up as early as age 55 with prolonged exposure to UV rays. But I also see ranchers in their 90s who have spent their entire lives outdoors and don't have significant cataracts."

Wearing sunglasses provides automatic protection against the sun's harmful rays only if the lenses are treated with an anti-UV coating.

"You're not going to know if there is an anti-UV coating unless there's a sticker on the sunglasses," Migues said. "Just because sunglasses are tinted doesn't mean they're protecting you from UV rays it just means they're dark."

In fact, wearing untreated sunglasses can be more dangerous than going without sunglasses. Behind dark lenses, the pupils open wider and expose more of their surface to the UV rays, Migues pointed out.

Although the anti-UV coating is transparent and can be placed on clear glasses, Migues doesn't recall any customer request to coat regular glasses. "It would be a good idea, though," he said. "UV rays penetrate through clouds, so on overcast days when people wear their regular glasses but not sunglasses, UV is still getting through."

Long-term exposure to sunlight can cause more than cataracts and wrinkles from squinting. Melanoma is a potentially life-threatening type of cancer that can result from excessive contact with UV rays. Blue-eyed, fair-skinned people are more at risk for this rare but serious type of tumor.

"I've only seen two cases of melanoma of the eye in the eight years I've been here," Migues said. "In the back of the eye, on the retina, pigment shows up the same as on the skin. I routinely check for eye freckles, and if there's a freckle back there, I watch it closely, just as you would watch a mole on your skin."

Going without UV-treated sunglasses while spending a day on the slopes or the lake can teach a painful lesson. "The glare off the water or snow is actually intense reflection of UV rays, and they can damage the surface cells of the cornea," Migues said. "This can cause sunburn pain so severe that it's impossible to keep your eyes open. Fortunately, the cornea generally recovers within 24 hours, and there is no lasting damage."

The eyes are fairly resilient, and Migues doesn't want anyone to panic about past failures to use protection. A single day in the sun during childhood or young adulthood is no cause for anxiety.

"If you go for years and years with no protection, and you have a predisposition for cataracts, you're adding to your chances of developing a problem earlier in life," he said. "But you can start wearing UV-coated sunglasses now, so why not protect yourself?"

Christine McKelvie is public relations director for Yampa Valley Medical Center.


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