Contact lenses are a popular alternative for those needing corrective eyewear, and have many advantages when compared to eyeglasses. Many people wear contact lenses for the aesthetics, while others are wear them because of their lifestyle. Some advantages to wearing contact lenses include improved athletic performance without the worry of glasses, improved peripheral vision, and the ability to wear sunglasses as needed. The key to wearing contact lenses successfully is choosing the right lens option for your needs along with diligent contact lens care.
RGP vs. Soft Contact Lenses
The first contact lenses available were the hard PMMA plastic contact lens materials. Later, RGP, or rigid gas permeable contact lenses became available. These RGP lenses provide the clearest visual acuity available with contact lenses, and are preferred for patients with moderate to severe astigmatism. They also are preferred for corneal degenerative diseases such as keratoconus and PMD. The disadvantage of RGP contact lenses is the discomfort experienced by patients in the early stages of wear.
Today, most patients are fit into soft contacts lens materials because of the significantly improved comfort of these lenses. The majority of today's lenses are made of a silicone hydrogel material which allow for longer wear schedules. These lenses are also available in a wide range of powers and also correct for a decent amount of astigmatism.
Hybrid contact lenses are a new option on the contact lens market, which have an RGP center allowing for superior optics, but with a soft contact lens edge allowing for superior comfort.
Soft contact lenses need to be replaced at different frequencies, depending upon the intended use and quality of the lens. Lens replacement can play a large role in contact lens safety and comfort.
For many years, conventional soft contact lenses were used, where one pair of lenses were used for an entire year. These lenses were strong enough to withstand 12 months of wear; however, they were not approved for overnight wear and often did not provide enough oxygen to the corneal surface.
Next, manufacturers started using a soft hydrogel material which allowed for greater oxygen permeability, and required more frequent contact lens replacement. These lenses are replaced every two weeks, allowing for less build up on the contact lens surface.
Today, many contact lens makers have adopted newer silicone hydrogel materials that further increase the oxygen permeability of the lens materials. Many of these lenses have 30 day replacement schedules, and allow for overnight wear of contact lenses. Monthly replacement schedules have demonstrated higher compliance among contact lens wearers.
Another increasingly popular contact lens option is daily replacement contact lenses. These lenses are designed to be disposed after one use, allowing the wearer to use a new pair every day. Daily lenses can significantly enhance contact lens comfort because they do not allow for protein build up on the lens surface. Daily wear also has the lowest chance for contact lens related pathology.