It's safe to assume that almost everybody is exposed to UV rays on a regular basis. But the possible dangers of long-term exposure to these unsafe rays are not often thought about, to a point where most people barely take enough action to protect their eyes, even if they're planning on being exposed to the sun for long periods of time. Being exposed to too much UV is unsafe and cannot be reversed, and can cause a number of severe, sight-damaging diseases later on in life. This means that ongoing protection from these rays is vital for everyone.
UV radiation, which comes mostly from the sun, consists of two sorts of damaging rays: UVA and UVB. Even though only minimal amounts of UVA and UVB light enter the inner eye, the ocular cells are very vulnerable to the harmful effects of their rays. Small amounts of this kind of exposure can easily cause sunburn of the eye, also known as photokeratitis. When the cornea receives UVB rays, the cells that make up its exterior are severely damaged, and this can be expressed as blurred vision, pain or even temporary blindness. UVA rays can actually enter the eye more deeply, causing harm to the retina. After several years, UV rays can lead to significant and lasting damage to eye sight. Of the 20 million people suffering from cataracts, an estimated 20 percent of cases are due to long-term UV exposure.
One of the best ways to protect your eyes from UV rays is with good eyewear. Ensure that your sunglasses or regular glasses block 100 percent of UVA and UVB rays. An unsatisfactory pair of sunglasses can actually be even worse than using nothing at all. Basically, if sunglasses offer no protection against UV, you are actually getting more UV rays. Such sunglasses tend to reduce the light, causing the iris to open and let even more light in. And this means that more UV will hit the retina. Always be sure that your sunglasses provide effective UV protection.
A wide brimmed sunhat or cap can also block roughly half of UV rays. These hats may also limit UV rays that hit the eyes from above or around glasses.
Long-term exposure to UV rays can also result in an abnormal tissue growth on the eye, known as pterygium. This is a slim, wedge-shaped tissue growth with blood vessels that grow over the white part of the eye's surface. In addition to being aesthetically unappealing, a pterygium can cause discomfort, and can even change the curve of the eyeball, which will cause astigmatism. If the pterygium begins to grow over the cornea, it can damage vision and may result in surgery. Because pterygia are caused by extended UV exposure, it's entirely avoidable.
Talk to your optometrist about all the different UV protection choices, which include adaptive lenses, polarized lenses and fixed tint sunglasses.