What is a common indication for prescribing rigid gas permeable lenses?

Rigid gas permeable (RGP) lenses are often prescribed for individuals with corneal irregularities because they can help to improve visual acuity and provide a smooth optical surface for light to enter the eye. These lenses are designed to maintain their shape on the eye, which provides better vision correction for conditions such as keratoconus or irregular astigmatism. The rigid structure of these lenses allows them to cover the irregularly shaped cornea effectively, creating a more uniform surface for light refraction.

In contrast, dry eyes can be a contraindication for RGP lenses because they can exacerbate discomfort. Myopia and presbyopia are typically managed with different types of lenses, such as soft contact lenses or multifocal lenses, which may be more effective for those conditions. Therefore, the specific capability of RGP lenses to address corneal irregularities makes them a suitable choice for that indication.