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Top Ten Things You Should Know About Contact Lenses

2008-03-06来源:
Soft lenses are perceived by most patients and practitioners alike to be more immediately comfortable while adequately correcting vision. They come in all formats - even toric and bifocal. Disposable soft lenses take minimal but important care to maintain their safety and usefulness.

Soft lenses do absorb elements from the tears and the environment. They can change in fit with their age and cleanliness, perhaps causing a lack of oxygen to the eyes. Their surfaces break down rapidly, causing a decreasing sharpness of vision.

On the other hand, many patients feel they see sharper and more clearly with rigid gas permeable (RGP) lenses. RGPs become very comfortable after adapting to them. They are easier and less expensive to maintain, last longer and are available in all formats. RGPs can more easily be custom designed to offer a wider range of vision correction than soft lenses. They can breathe more oxygen, don't deteriorate as fast and don't absorb things as easily as soft lenses.

2. Soft lenses generally center by themselves if they fit well. Just put them straight on the cornea and they will go where they belong. Use the iris, the colored part of the eye, as a guide. Make sure you have a competent eye care practitioner evaluate the fit of your lenses before you wear them, though. Improperly fit soft lenses can cause damage to your eyes!

3. Almost all nearsighted people can wear contact lenses, no matter how high their prescription. In fact, there are contact lens laboratories that make custom lenses up to -30.00 diopters! It is essential to follow your contact lens practitioner's rules, however. Contact lenses are extremely safe when prescribed and cared for properly.

4. Improperly worn contact lenses can cause a loss of oxygen to the cornea, which in turn can lead to blood vessels growing over the front of your eyes, infections, lid changes, allergies, corneal warping, corneal swelling and possibly even blindness.

5. Do not share contact lenses with your friends. Everyone's tears are filled with normal bacteria, but transferring these bacteria to someone else's eyes is not a good idea. And not only is there a risk of infection, if the lenses don't fit, the eye can suffer from a lack of oxygen or develop other problems.

6. Contact lenses are medical devices. Changing parameters should be done under the supervision of an eye care practitioner. Do not take chances!

7. If you sunbathe while wearing contact lenses, there is no problem with heat. But your corneas can swell and make your lenses fit tighter, causing some temporary redness and irritation. Put some form of lubricating drops in your eyes before tanning. Wear protective glasses to block the really harmful UV radiation from getting to your eyes - it has been linked to cataracts, macular degeneration, etc.

8. Bloodshot eyes are a sign that something is not right. It could be as simple as a solution allergy or dirty lenses. But it could also be a sign that your corneas are not getting enough oxygen. Go see your eye care practitioner and find out why your eyes are so red!

9. Eyeglass prescriptions are higher than contact lens prescriptions because contact lenses sit on the eye, whereas eyeglasses sit in space in front of the eye. This is called the vertex distance. The closer a lens sits to the eye, the less strength is needed to focus light on the retina. And the stronger the prescription, the more the power adjustment. This is true for both soft and RGP lenses.

10. Some contact lens practitioners find that lenses with lower water content can sometimes be better for people who have dry eyes. But some patients actually do better with high-water contact lenses. It has long been felt by some practitioners that the thicker the lens, the better, as well.

Are you planning to wear contact lenses? Visit Contact Lenses Center for the latest news and information on contact lenses.