Spherical rigid gas-permeable (RGP) lenses can be used to mask low levels of corneal astigmatism in patients who can tolerate RGPs.

 

Because almost all (if not all) astigmatism results are from the front surface of the cornea, GP lenses are an ideal solution. Because it is rigid, an RGP can mold the tear film on the front of the eye into a spherical shape. This will correct the astigmatism resulting in very good vision.

 

In very high astigmatism, a so-called "bitoric" lens-design can be used. This type of lens has a different back surface curve to provide a better fit, as well as, to significantly improve vision.