Today there are many options for contact lens wear. Contact lenses come in different sizes, different chemical compositions, varying degrees of hardness or softness, clear and in colors, and with varying wearing schedules. Lenses are generally worn as daily wear or extended wear (during sleeping hours). The United States Food & Drug Administration (FDA) approves contact lenses for daily wear and extended wear based on a number of factors including amounts of oxygen transmitted to the cornea of the eye.
Daily wear lenses are normally removed every evening or after a waking days wear, and cleaned, disinfected. The contact lenses are reinserted after a minimum of six hours depending on the cleaning system used.
Most extended wear lenses are FDA-approved to be worn for no more then seven (&) days. At present, he only soft lens approved for longer then seven days is Ciba Visions Focus Night & Day lens. This lens is approved for thirty (30) days. The only gas permeable lens approved for night wear is Paragons CRT lens used to reduce myopia. The rigid gas permanent lens (RGP) with the longest continuous wear is the Menicon Z lens approved for thirty (30) days.
Contact lenses are made of many different types of plastic, but they are divided into two main groups: soft or rigid gas permeable. Soft contacts contain from 25-79% water, are easy to adjust to and are quite comfortable. Rigid gas permeable contact lenses take longer to adjust to, but are more durable and more resistant to deposit buildup. They tend to be less expensive over the life of the lens (but the upfront cost is higher) and can offer some people crisper vision than they would get with soft contacts.
The replacement schedule of a contact lens refers to how long you can safely wear it before you need to throw it away. With RGPs, you generally replace them every several years; because they're so hardy, it doesn't make sense to replace them more often. Soft contact lenses come in a wider variety of replacement schedules:
Contact lenses are fit to your individual eyes needs. Oxygen demand, corneal dimensions, conjunctival dimensions and tear film quality and quantity, all playa role in determining which lenses are correct for you. This is as true for non prescription color lenses as it is for prescription lenses.
Soft contact lenses are available for:
Rigid Gas Permeable lenses are available for:
For to fit eyes due to size and or shape
Bifocal Astigmatic prescriptions
For Corneal Transplant irregular astigmatism
Kerataconus prescriptions OrthoK prescriptions
Corneal Refractive Therapy
For additional information and questions about contact lenses, Call or e-mail me