- Astigmatism occurs when the cornea is shaped like an oblong baseball whereas normal cornea is spherical football. This causes light rays to focus on two points beside the retina.
- Astigmatism induces distortion of vision.
- Astigmatism can be associated to myopia or hyperopia.
- Correction of astigmatism by glasses, contact lenses or refractive surgery focuses light rays on one point of the retina.
PRK and Lasik surgery are able to correct astigmatism by shaping the cornea and making it spherical.