subject: Sunglasses - A Perfect Way To Protect Your Eyes [print this page] Ultraviolet light not only damages skin, exposure to UVA and UVB causes eye damage too. It is important to choose sunglasses carefully to reduce damage caused by UV rays. Various eye problems have been associated with overexposure to UV radiation. As an example, UVB rays are thought to help cause pingueculae and pterygia. These growths on the eye's surface can become unsightly and cause corneal problems as well as distorted vision.
In high short-term doses, UVB rays also can cause photokeratitis, a painful inflammation of the cornea. "Snow blindness" is the common term for severe photokeratitis, which causes temporary vision loss usually lasting 24-48 hours. The risk for snow blindness is greatest at high altitudes, but it can occur anywhere there is snow if you don't protect your eyes with UV-blocking sunglasses.
Because the cornea appears to absorb 100 percent of UVB rays, this type of UV radiation is unlikely to cause cataracts and macular degeneration, which instead are linked to UVA exposure.
Some sunglasses are better designed to protect your eyes than others. Here's some advice on selecting sunglasses. You cannot tell how much UV radiation a pair of sunglasses will block based on the color or darkness of the lenses. The darkness of the lens does not indicate its ability to shield your eyes from UV rays and many sunglasses with light-colored tints, such as green or amber, offer the same UV protection as very dark lenses.
Large, wrap-around style frames may provide more efficient UV protection because they cover the entire eye-socket and block UV rays from sneaking in from the side. This is especially important when doing activities around or on water or snow because UV is reflected from all directions off of the surfaces. For sunglasses to be fully protective against UV radiation the lenses must absorb all UV radiation and side protection should be provided.
Always check the sunglasses label to make sure they protect against UVA and UVB. The closer to 100% protection a pair of sunglasses provides, the safer your eyes will be from damage.
