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Contact lenses, like eyeglasses or vision surgery, can correct nearsightedness, farsightedness and astigmatism. About 20 percent of Americans who need vision correction for these refractive errors wear contact lenses.
While some people enjoy making a fashion statement with eyeglasses, others prefer their appearance without them. Contact lenses offer the ability to be glasses-free without expensive vision surgery. Contacts also provide a wider field-of-view than glasses, which is great for driving and sports.
Contact lenses have been around for more than a hundred years, and today just about everyone can wear contact lenses. If you were told in the past that you couldn't wear contacts, odds are you can today. There are more convenient and healthy contact lens options than ever, including many contact lenses that can correct astigmatism.
The first step in being fitted for contacts is to see an eye doctor for a comprehensive eye exam. In the United States, contact lenses are considered medical devices and must be prescribed and properly fitted by an eye care professional (ECP). Your ECP will evaluate your visual needs, your eye structure, and your tears to help determine the best type of contact lenses for you.
Contact lenses are classified according to:
There are four types of contact lenses, based ion the material they are made of:
The most popular contact lenses worn today are a special type of soft lens called silicone hydrogel lenses. These lenses allow more oxygen to pass through them than conventional soft lenses, reducing the risk of contact lens discomfort and complications.
There are two types of contact lenses based on recommended wearing time:
"Continuous wear" is a term that's sometimes used to describe 30 consecutive nights of lens wear — the maximum wearing time approved by the FDA for certain brands of extended wear lenses.
Even with proper care, contact lenses (especially soft contacts) should be replaced frequently to prevent the build-up of lens deposits and contamination that increase the risk of eye infections.
Soft lenses have these general classifications, based on how frequently they should be discarded:
Gas permeable contact lenses are more resistant to lens deposits and do not need to be discarded as frequently as soft lenses. Often, GP lenses can last a year or longer before they need to be replaced.
Several contact lens designs are available to correct various types of vision problems:
Custom soft and GP lens designs also are available for hard-to-fit eyes, including eyes with keratoconus.
The first step in finding the best contacts for you is to schedule a comprehensive eye exam and contact lens consultation with your eye doctor. During this exam, your doctor will make sure your eyes are healthy enough to wear contact lenses and advise you regarding what to expect when wearing contacts.
Next is the contact lens fitting itself. Detailed measurements of your eyes are taken, and trial lenses often are applied to achieve the best possible fit and determine if you can comfortably wear contacts.
A contact lens fitting takes several office visits and you will be asked to return a number of times to make sure the lenses continue to fit properly and remain comfortable after prolonged periods of wear. In some cases, changes of lens size or design are needed before the fitting process is complete.
Your prescription for contact lenses is written only after the contact lens fitting process is completed and your doctor is satisfied with the long-term fit of your lenses and how well your eyes tolerate contact lens wear.
Caring for your contact lenses — cleaning, disinfecting and storing them — is much easier than it used to be. In most cases today, only a single care solution is required for cleaning, rinsing and storing your lenses. And if you choose daily disposable soft lenses, routine lens care can be eliminated altogether.
Your eye doctor or contact lens technician will teach you how to apply, remove and care for your lenses during your contact lens fitting.
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