Astigmatism is a condition in which an abnormal curvature of the cornea can cause two focal points to fall in two different locations – making objects up close and at a distance appear blurry. Astigmatism may cause eye strain and may be combined with nearsightedness or farsightedness. Eyeglasses, contact lenses, or corrective surgery may help to correct or improve the condition.
Astigmatism makes it hard to see fine details of objects, either close up or from a distance. Though common, the cause of astigmatism is unknown. It is usually present from birth, and sometimes occurs after certain types of eye surgery.