Types of Contact Lenses

What are the different types of Contact Lenses?
There are two general categories of contact lenses – soft and rigid gas permeable (RGP). All contact lenses require a valid prescription.

Soft Contact Lenses
Rigid Gas Permeable (RGP) Contact Lenses
Extended Wear Contact Lenses
Disposable (Replacement Schedule) Contact Lenses
Lens Comparison
Specialized Uses of Contact Lenses
Orthokeratology (Ortho-K)
Decorative (Plano) Contact Lenses
 

Soft Contact Lenses
Soft contact lenses are made of soft, flexible plastics that allow oxygen to pass through to the cornea. Soft contact lenses may be easier to adjust to and are more comfortable than rigid gas permeable lenses. Newer soft lens materials include silicone-hydrogels to provide more oxygen to your eye while you wear your lenses.



Rigid Gas Permeable (RGP) Contact Lenses
Rigid gas permeable contact lenses (RGPs) are more durable and resistant to deposit buildup, and generally give a clearer, crisper vision. They tend to be less expensive over the life of the lens since they last longer than soft contact lenses. They are easier to handle and less likely to tear. However, they are not as comfortable initially as soft contacts and it may take a few weeks to get used to wearing RGPs, compared to several days for soft contacts.



Extended Wear Contact Lenses
Extended wear contact lenses are available for overnight or continuous wear ranging from one to six nights or up to 30 days. Extended wear contact lenses are usually soft contact lenses. They are made of flexible plastics that allow oxygen to pass through to the cornea. There are also a very few rigid gas permeable lenses that are designed and approved for overnight wear. Length of continuous wear depends on lens type and your eye care professional’s evaluation of your tolerance for overnight wear. It’s important for the eyes to have a rest without lenses for at least one night following each scheduled removal.



Disposable (Replacement Schedule) Contact Lenses
The majority of soft contact lens wearers are prescribed some type of frequent replacement schedule. “Disposable,” as defined by the FDA, means used once and discarded. With a true daily wear disposable schedule, a brand new pair of lenses is used each day.

Some soft contact lenses are referred to as “disposable” by contact lens sellers, but actually, they are for frequent/planned replacement. With extended wear lenses, the lenses may be worn continuously for the prescribed wearing period (for example, 7 days to 30 days) and then thrown away. When you remove your lenses, make sure to clean and disinfect them properly before reinserting.



Lens Comparison
The American Optometric Association ( http://www.aoa.org/x1827.xml ) has more detailed information about contact lenses including a lens comparison chart.