Rigid gas permeable

Rigid gas permeable lenses are rigid contact lenses made of oxygen-permeable polymers. Initially developed in the late 1970s, and through the 1980s and 1990s, they were an improvement over prior 'hard' lenses that restricted oxygen transmission to the eye.

Rigid lenses are able to replace the natural shape of the cornea with a new refracting surface. This means that a regular (spherical) rigid contact lens can provide good level of vision in people who have astigmatism or distorted corneal shapes as with keratoconus. However, they are not as comfortable as soft contact lenses, and require a period of adaptation before full comfort is achieved ^[1].

References

1. ^ Terry et al., CLAO J (1986) 15:305

External links

• Use of rigid gas permeable lenses in Keratoconus