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Prolonged exposure to the ultraviolet rays in sunlight can
cause serious eye damage. As we head into the summer season, an
expert recommends some simple and effective ways to protect
your eyes from harmful UV rays.

As the weather warms up and we spend more time outside,
ultraviolet (UV) rays pose a greater risk, not just to our skin
but also to our eyes. UV light can damage eye tissue and cause
serious vision problems.

"There are a number of potentially harmful effects of UV
radiation," explains Dr. Eric Postel, an associate professor of
ophthalmology in the Vitreoretinal Service at Duke University Eye Center.

"UV exposure can cause keratitis, an inflammation or
infection of the cornea, as well as tissue growths called
pterygia, and other processes. UV rays can also increase the
risk for cataracts. There are some suggestions that UV light
may be a risk factor for macular degeneration, although that's
not entirely borne out yet in all studies."

Postel said the incidence of UV-related eye damage is far
greater in populations near the equator and in persons who
spend a great deal of time outdoors.

"Look at the data on cataracts, for example. One of the
earliest studies, back in the 1980s, came from a study of
Chesapeake Bay watermen. They found that the guys who wore hats
or sunglasses had a far lower incidence of cataracts than those
who did not, about three times lower. Someone who works outside
is at greater risk."

Fortunately, said Postel, there are some simple and
effective preventive measures we can all take to reduce the
risk of eye damage from UV radiation. Your best protection
comes from wearing a hat with a brim, using sunblock, and, most
important, wearing sunglasses.

Here are some recommendations when selecting sunglasses:

UV protection:

"All you're really looking for is that the sunglass itself
blocks 100 percent of UV light. Another way it's sometimes
listed is that it is absorbing or blocking light up to 400
nanometers in length. Price is not necessarily an issue here,
nor is brand."

Style:

"Certainly there is access of light around any sunglass. The
smaller the sunglass, the more likely that light will get
around it. So a larger lens, or one that's wraparound may
provide more protection, as would a hat with a brim."

Polarization:

"Polarized lenses don't provide any more protection against
UV light, but they do tend to limit the amount of glare to
which you're subjected. Basically, what is happens is, you get
light oriented in different planes and polarized lenses block
one of those planes, such that you will get less glare off a
horizontal surface, for example at the lake or skiing or
driving."

Color:

"It's personal taste. There really is not a better lens
color. You may find that in certain lighting conditions, such
as skiing on a lake, you may want a certain color. But in terms
of protection for the eye, as long as they block 100 percent of
the UV light, it doesn't matter."

"All you're looking for on the label, and what I've looked
at in local shops, is that the label says there is a certain
percentage of UV light that's blocked. It may say UVA-UVB, but
all you want is UV. There is a third type, UVC, that's actually
blocked in the upper atmosphere, as long as we have all the
components up there. But there's not an SPF factor like you
have with skin sunblocks."

Since children typically spend so much time outdoors,
especially during the summer months, Postel says it's important
to make sure they wear sunglasses and that the lenses are
impact-resistant.

"Certainly, children who are outside much more frequently
than adults are more susceptible to sun damage. We're much more
aware of this nowadays than when I was a child. Excluding those
people who have diseases that may sensitize them to the sun,
the damage you receive from UV light is cumulative. So first of
all, you don't want to ignore protection for your
children."