What is Astigmatism? Astigmatism is a common vision condition caused by an irregular shape of the cornea or lens. Instead of having a perfectly round curvature, the eye is shaped more like a football, causing light to focus unevenly on the retina. This results in blurred or distorted vision at all distances. Astigmatism occurs when the cornea or lens has an uneven curve. Because of this irregular shape, light entering the eye does not focus evenly on a single point on the retina, leading to blur...