2007年12月15日星期六

Contact Lenses - Simple Tips And Facts For Shoppers

Contact lens sales are regulated by the FDA (Food And Drug Administration) and the FTC (Federal Trade Commission.) In the U.S. contact lens marketplace, 82 percent wear soft lenses, 16 percent wear rigid gas-permeable, and only 2 percent wear hard. There are 75 million contact lens wearers worldwide and 31 million in the U.S. alone.

Among the many kinds of contact lenses you can buy are: novelty, colored, crazy, Halloween, special effects, theatrical, costume, scary, glow in the dark, wild eyes, mirrored, black, white, and red. All correcting contact lenses must have a valid prescription from an ophthalmologist or optometrist.

With planned-replacement lenses, the doctor works out a replacement schedule tailored to the needs of each patient. Rigid gas permeable contact lenses are more durable, resistant to deposit buildup, and generally give a clearer, crisper vision. Some doctors prescribe disposables as planned-replacement lenses, which are removed, disinfected, and reused before being discarded.

Soft lenses are easier to adjust and are much more comfortable than rigid lenses, because they conform to the eye and absorb and hold water. There are differences in the water content and shape of the lens between different brands. Soft lenses have the added benefit in that soft lenses aren't as likely as rigid lenses to pop out or get foreign material like dust underneath.

Soft contact lenses are made of soft, flexible plastics that allow for oxygen to pass through to the cornea. Rigid lenses generally give you more clear vision. There are several types of lenses including: soft contact lenses, rigid gas permeable lenses, extended wear lenses and disposables.

Rigid gas permeable lenses tend to be less expensive over the life of the lens since they last longer than soft lenses. People who have good distance vision but need help for reading can get a monovision reading lens for one eye.

Check to see if you have a health insurance plan that includes vision coverage. When you place your order make sure your lenses are available and not out of stock, because you'll need them now. When you receive your order, if you think you've received an incorrect contact lens, check with your doctor or eye care professional right away; don't accept any substitution unless your eye care professional approves it.

Before you buy online, check to see if there are any testimonials at the online supplier's website. You can buy contact lenses from an eye doctor, on the Internet, from an optical store or a warehouse club. When you place your contact lens order, request the manufacturer's written patient information for your contact lenses; it'll give you important risk and benefit information as well as instructions for use.

Ask about prices at your doctor's office when you have your eye examination, or during a follow-up visit after you get your prescription. Always ask what rebates are available. Carefully check to make sure the company gives you the exact brand you ordered, the name of the lens, the power, sphere, cylinder, if any, axis, if any, diameter base curve, and peripheral curves, if any.

Basic rule: never swap your contact lenses with anyone else. The FDA has approved extended-wear lenses for use up to seven days before removal for cleaning; but there are risks with use of extended-wear lenses even for one night. Soft extended-wear lenses bind down on the closed eye, but they are porous and allow some tears through during sleep; because they have so little form, their binding has very little effect on the shape of the eye.

Under the binding down of a rigid contact lens during sleep, the flow of tears and oxygen to the cornea is reduced; lack of oxygen leaves the eye vulnerable to infection. To be sure your eyes remain healthy you shouldn't order lenses with a prescription that's expired or stock up on lenses right before the prescription is about to expire; it's much safer to be re-checked by your eye doctor. Be aware that extended-wear (overnight) contact lenses - rigid or soft - increase the risk of corneal ulcers, which are infection-caused eruptions on the cornea that can lead to blindness; symptoms include vision changes, eye redness, eye discomfort or pain, and excessive tearing.

Laser surgery and its risks can be frightening and too expensive for some people; contacts can provide a safe, comfortable and time-tested alternative. Make sure to visit a reputable eye doctor for a complete eye examination once a year, or more frequently if needed. Ordering contact lenses online has never been simpler with, and sometimes without, a credit card.