Gas Permeable (GP) Lenses

Potential patients often ignore the many advantages that these lenses offer. They associate the modern gas permeable (GP) lens with the old 'hard' lenses, and tales of red-eyes and irritation. The modern Rigid Gas Permeable (RGP) lens can offer patients all day comfort with the quality of vision normally only achieved with glasses. Because the lens is rigid, it will not flex or distort on an irregular cornea, so if a patient has astigmatism, as do many individuals, a soft hydrogel or silicone hydrogel lens may offer slightly compromised visual acuity due to the lens flexing. An RGP lens will also transmit the levels of oxygen only recently achieved with silicone hydrogel lenses and so the incidence of complications or infections with these GP lenses are far lower than other lens types. They are also durable and so will last for much longer than other lens types, and the upkeep costs of solutions tend to be less expensive.

Modern designs of RGP lenses - notably semi-scleral designs - offer improved comfort and vision for complicated prescriptions that were not previously available. Keratoconus sufferers can now be fitted, whereas several years ago they struggled to achieve satisfactory vision and comfort. For those older patients who require bifocals, RGPs offer greater options than soft hydrogel and silicone hydrogel designs.

Another exciting development over recent years is the Ortho-Keratology field. A specially designed RGP lens is worn overnight to re-shape the cornea. After several nights' treatment, the patient can see without glasses. The process is totally reversible and the patient uses the lens most nights to mould the front of the cornea in order that vision is clear during the following day.

In other words – do not write off RGP lenses! The developments and results achieved in this method of eye correction still have much to offer patients who demand the highest standard of vision correction.