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Transcripts: 533-1 and 533-2
Week: 533.1 Guest: Dr. Donald G. Pitts, Optometry, Ret. Prof., Univ. Of Houston Topic: UV Rays and The Eyes- Part One Producer/Host: Steve Girard
NEMA: We know about the dangers of the sun where our skin is concerned...though many of us still don't take precautions, but the sun can cause serious damage to our eyes...but taking precautions can be, well, cool...with the right pair of sunglasses. We're with Dr. Donald Pitts, a retired Professor of Optometry at the University of Houston....
PITTS: Well, sunlight can do a number of things to unprotected eyes, and a number of them are permanent, but most of them come along very, very gradually. Let's enumerate some of them: One of them is if you're in the sunlight a lot, as you grow older, your cornea becomes thinner. Another one is that you can get cataracts...of the lens of the eye, and I think many of the older people in the country know that's one of the leading causes of blindness. A third thing is you can have damage to the retina. And, even though not all scientists agree, as to the full extent of the damage, we all agree that the damage that's been done is irreversible. So these are the areas that are very serious as far as I'm concerned, and require protection in sunlight.
NEMA: What do you tell people to look for when looking for eye protection?
PITTS: Well, there are several things I think they should look for, and there are several things they should do...one of them, they should get a lens that controls ambient luminance when you're outside...in other words, it controls the visible part of the spectrum. Because what happens if you stay out in sunlight, over two hours of time, during the daytime, you reduce your ability to see at night by 50%. The second thing we need to do is eliminate part of the spectrum that causes damage, and we just talked about it...and ultraviolet is the major part. And the third thing we need to do when selecting a sunglass is make certain we have normal color vision. Because some of the sunglass lenses that are sold on the market actually are dangerous, because they eliminate the ability of normals to see the traffic lights..extremely green color lenses will eliminate your ability to see the red in a traffic light. Its very, very important to remember that you can get color shifts, and you want to stay with a good, neutral or gray tint to give you good color vision.
NEMA: What about those very dark sunglass lenses you see some people wearing?
PITTS: This has become a fashion fad in the last two years, and unfortunately, its not desirable, because if you get the transmittence in the lens down below ten percent of the light you're looking at, you begin to lose your ability to see well. Consequently, real dark filters are not desirable, except in certain occupational conditions.
NEMA: Dr. Pitts says older folks have never really gotten into the habit of protecting their eyes with sunglasses...and so that generation has a higher incidence of cataracts than younger people. He also says the pupils get smaller when you get older, so older people need more light to see as well as they can...and that's another reason they won't wear sunglasses. Dr. Pitts believes you should make sure your regular eyeglasses have a UV protective coating, because you can get a dose of UV light from working in an area lighted by fluorescent bulbs. I'm Steve Girard.
Week: 533.2 Guest: Dr. Donald G. Pitts, Optometry, Ret. Prof., Univ. Of Houston Topic: UV Rays and The Eyes- Part Two Producer/Host: Steve Girard
NEMA: Once again, we're talking with retired University of Houston Optometry Professor Dr. Donald Pitts...about protecting our eyes from the long-term effects that can be caused by sunlight. What are the signs that someone is having problems with their eyes caused by UV radiation?
PITTS: The first sign is usually that the individual notices the eyeball itself, the white part of the eye, becomes bloodshot. ..okay, this indicates you've got an inflammation there. The second sign that these people will give you is they'll feel like they have sand in their eyes. Those two are the two most differentiating symptoms that people who have had too much sunlight will describe for you. And if you have skiers, that snow is reflecting another 85 to 95 % of that ultraviolet radiation right back into their face. And if they don't have good protection, at night, when they go in, they will begin to experience these symptoms. Then the last thing that happens is, because of the conditions we've just talked about, indicates the swelling of the cornea. Then you're ability to see well will drop off....it will come back, in a period of 24 to 36 hours, but there's no need in stressing yourself, you can protect against it.
NEMA: What about those people who pop their lenses directly in their eyes...how do they make sure their eyes are protected from the sun?
PITTS: Now, we're talking about contact lenses. Now, how do they get the protection? Well, one...they can get it in the contact lens...there are not very many lenses there that they have a choice for. ..but they can get that. But number two is...they can get it by wearing sunglass lenses all of the time when they're outside. Now, one other thing that they need to think about is, that one of the fastest growing skin cancers in the United States is the eyelids, the outside of the eyelids. Consequently, these contact lens wearers need to add to their protection to the interior of the eye....they do a beautiful job there with good UV absorbing contact lenses...they need to add a sunglass, or a clear lens, whichever they choose, just make certain its full UV protection.
NEMA: Another bright spot...the beach....
PITTS: When people are on the beach, many people will go to the beach, put out a white umbrella, and lay under the umbrella and think they're being protected. About 35% of the UV radiation that hits that beach is reflected up into the white umbrella, and about 15 to 20 % of that is reflected back down, so that the individual under the umbrella....that umbrella acts as a lens and concentrates on them, they're getting almost as much UV radiation laying under the umbrella as you would if you just throw the umbrella away.
NEMA: Dr. Donald Pitts says, for comparison, your lawn reflects three and a half to five percent of UV radiation. The beach reflects about 35%. And the snow, 85 to 95 %. So, give a lot of thought to using sunglasses with complete UV light protection...and consider getting eyeglasses or contact lenses with a protective coating...it could help prevent the development of cataracts or retinal damage over the years. I'm Steve Girard.
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