While contact lenses have been available for many years, it was only in 1938 that the first practical contact lenses were fitted. However, since then there have been many developments in lens designs, manufacturing techniques and lens materials that have greatly improved their quality and performance resulting in millions of people achieving clear comfortable and effective vision without the use of spectacles.
There are two broad categories, the soft lens which is very widely utilised providing clear comfortable and safe correction of vision. However, they are not suitable for all defects and require frequent replacement.
On the other hand, rigid gas permeable (RGP) lenses are suitable for correction of a wide variety of focusing errors with excellent optical correction, requiring less frequent replacement and consequently are more economical in the long-term.
RGP lenses also have the advantage of correcting conditions such as keratoconus which in many cases cannot be corrected with a soft lens. Another more recent technique called Orthokeratology, or Ortho K, is especially suitable for myopia (shortsightedness) correction. It involves wearing a contact lens during sleep which corrects the myopia by reshaping the front of the eye thereby eliminating the need for glasses or contact lenses during the day. This technique has the added advantage in young people of arresting or slowing the development of myopia which in turn reduces the risk of glaucoma, retinal detachment and macular disease.
A comprehensive vision eye examination and assessment of individual patient needs is required before any recommendation can be of made regarding the preferred lens design.
