Contact Lenses
Since people of all ages enjoy very active lifestyles, it is not surprising that more and more people are choosing contact lenses instead of glasses for their vision correction. Some advantages of contact lenses include better peripheral vision and less visual distortion compared to eyeglasses. Many people also prefer the comfort of contact lenses, which do not exert pressure on the ears and nose the way eyeglasses do.
Two basic types of contact lenses are rigid gas permeable (RGP) and soft lenses. RGP lenses are made of harder plastic, while soft lenses are made of more pliable plastic. For this reason, soft lenses are generally more comfortable than RGP lenses. RGP lenses, however, are more durable and may provide better clarity of vision compared to soft lenses. Most contact lens wearers in the United States (about 82%) are soft contact lens wearers.
There are different types of soft contact lenses, depending upon how often the lenses are discarded. Most people choose disposable soft contact lenses, which are thrown away and replaced on a monthly, biweekly, or daily basis. This modality of wear provides the clearest vision, as well as superior comfort and better ocular health. In addition, maintenance and cleaning of disposable contact lenses is greatly simplified compared to nondisposable lenses, creating greater convenience. A smaller percentage of people wear conventional soft lenses which are replaced about once per year. A major disadvantage of this type of lens is the buildup of deposits and film that occurs as the lenses age, making them less comfortable, less oxygen permeable and less transparent than brand new lenses.
There are both soft and gas permeable contact lenses that have been approved by the Food and Drug Administration for extended wear. An extended wear contact lens is one that has been FDA approved for continuous overnight wear. In the past, extended wear lenses have been associated with an increased risk of ocular complications (described below) and have, therefore, not been recommended. There are, however, newer contact lens materials that provide significant oxygen permeability, which may reduce the risk of these complications.
While contact lenses are relatively safe to wear, there are risks associated with their use. Such risks include eye infection, eye inflammation, corneal abrasions and corneal ulcers. Some of these conditions can result in permanent loss of vision. For this reason, contact lenses are considered medical devices, which can only be obtained with a valid prescription written by a licensed eye care practitioner. In addition, eye doctors will ask that contact lens wearers return for regular eye evaluations in order to reduce the incidence of ocular complications. Fortunately many of the risks associated with contact lens wear are reduced when patients strictly adhere to the recommendations given to them by their eye doctor regarding the proper care and use of their contact lenses.
Certain patients may not be good candidates for contact lenses. Some conditions that may interfere with successful contact lens wear include dry eye, ocular allergy, eyelid or eye inflammation, or a history of eye infection. Check with your eye care practitioner to determine if you are a candidate for contact lens wear.