Astigmatism (uh-STIG-muh-tiz-um) is a common, mild and generally easily treatable imperfection in the curvature of your eye. The condition can cause blurred vision.
Astigmatism occurs when the front surface of your eye (cornea) or the lens, inside your eye, has a slightly different surface curvature in one direction from the other. Instead of being even and smooth in all directions, the surface may have some areas that are flatter or steeper.
Astigmatism blurs your vision at all distances. Astigmatism is often present at birth and may occur in combination with nearsightedness or farsightedness. Often it's not pronounced enough to require corrective action. When it is, your treatment options include corrective lenses and surgery.