Contact lenses are an alternative to glasses. Invented more than 100 years ago, they were first made from glass and later hard plastic.
Today, contact lenses are made from soft plastic. They are small, thin discs designed so that you can place them directly on the surface (cornea) of the eye. Most often, eye doctors, or other licensed eye care professionals, prescribe contact lenses for vision problems such as nearsightedness, farsightedness and uneven focus (astigmatism). Eye doctors may also prescribe them to treat certain eye conditions and diseases. For example, people who have had cataract surgery, and who did not receive lens implants, may use special contact lenses.
If you are thinking about getting contact lenses, there are two things you need to do first.
1. Learn the facts about contact lenses
2. Visit your eye doctor
If you want to wear contact lenses, you must first schedule a visit with an eye doctor or other licensed eye care provider. Because contact lenses are medical devices, they need to be properly fitted by an eye care professional. This is true even if you don't wear glasses and just want to wear contacts to change your eye color.
Once the eye doctor checks your eyes to make sure it's okay for you to wear contacts, then he or she can write you a prescription for contact lenses.
Not everyone who needs glasses wants to wear contacts, but nine out of 10 people who want to wear them can wear contacts. However, contact lenses may not be a good option for people who:
There are several types of contact lenses. The most common are soft and hard (rigid gas permeable). Gas-permeable lenses allow more oxygen to reach the surface (cornea) of the eye.
Soft contact lenses come in two basic forms—daily wear and extended wear. Both lenses are made from thin, flexible, material and water. Daily-wear lenses must be removed, cleaned and stored every day. Extended-wear lenses are designed for overnight wear. However, there is an increased risk of infection associated with extended-wear lenses. They should be worn for the period of time prescribed by your eye doctor.
Hard contact lenses offer clearer vision with certain eye conditions, and specific types may last longer. Many types of hard contact lenses are available in bifocals. It may take longer to adapt to wearing hard contact lenses than soft contact lenses. Hard contact lenses may slid out of place more easily when you engage in vigorous physical activity or sports.
Daily-wear soft lenses are the most comfortable, and your eyes will adjust to wearing them in less time than with hard contact lenses. Soft lenses may be worn during vigorous physical activities and playing sports with less likelihood that the lenses will slip out of place. They are available in a variety of tinted colors. Some people may not have clear vision wearing soft contact lenses due to certain eye conditions such as severe astigmatism. Soft contact lenses need special cleaning and disinfection and tear easily, so they may not last as long as hard contact lenses. Disposable soft contact lenses are replaced every day to every few months, depending on the type of lens.
Extended-wear soft lenses offer the same advantages as daily-wear lenses. These lenses may be worn for an extended period, up to a week. However, due to the risk of infection associated with extended use, daily removal and cleaning is recommended.
How long it takes the eyes to adjust to wearing contacts depends on the person and the type of lens. Hard contact lenses may take several weeks to two months before they can be worn comfortably for any length of time. Soft contact lenses usually only take several days to a week. At first, contact wearers may experience some irritation, redness, tearing, sensitivity to light and occasional blurred vision. People with dry eyes may have greater difficulty adjusting to and wearing contact lenses, and may have a greater risk of eye damage.
Any time a foreign object or material is placed in the eye, there is an increased risk of problems. That's why it's important to follow your eye doctor's instructions about care and cleaning of your lenses, and see your eye doctor for regular follow-up exams.
If you experience any of the following problems, contact your eye doctor:
Care and cleaning of contact lenses depends on the type of lens. All lenses need regular, thorough cleaning and storing. Daily-wear and extended-wear users must be especially careful to follow the recommended regimen of lens cleaning, rinsing, disinfecting, enzymatic cleaning and lens case cleaning.
For all lenses, always buy commercially prepared sterile solutions. Never use home-made saline solutions! They are dangerous. Your eye doctor can provide information and instructions for proper care of your contact lenses.
Cosmetic contact lenses, often called zero-power or plano contact lenses, can make quite a fashion statement. But when these lenses are bought without a prescription at boutiques, beach shops, tattoo parlors and other nonprofessional retailers, they pose serious health risks.
People, teenagers in particular, have nearly lost their sight as the result of using nonprescription lenses.
Always visit an eye doctor to be fitted for contact lenses. Always wear contact lenses under the supervision of an eye doctor.
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