Astigmatism often refers to a cornea that is oval in shape, rather than round shaped. The oval shape of the cornea causes light to focus on more than one point in the eye, resulting in blurred vision. Astigmatism typically occurs along with nearsightedness and farsightedness.

Astigmatism can easily be detected in a routine eye examination, during refraction. Astigmatism can be corrected with glasses, contact lenses or refractive surgery, such as astigmatic keratotomy or LASIK. These surgeries essentially reshape the cornea, so it becomes more spherical and uniformly curved.