The Effects of Radial Keratotomy on the Asphericity of the Cornea

Radial Keratotomy (RK) causes at least three different changes in the shape of the corneal surface. Each change alters the optical properties of the surface. The first alteration is a flattening in the base curvature of the eye, which modifies the overall optical power of the eye. A second more subtle change is in the asphericity of the cornea. The asphericity of the cornea does not affect the overall power of the eye, but influences visual performance by controlling the amount of spherical aberration in the eye. Finally, there are higher-order variations in the corneal surface resulting from the RK incision pattern, which can cause a more complex change in visual performance.