Astigmatism is a common refractive error caused by an irregularly shaped cornea or lens. Rather than being perfectly spherical (like a basketball), the cornea or lens has an oblong shape (more like a football), which prevents light from focusing properly on the retina.

This vision condition causes blurred or distorted vision at all distances. People with astigmatism often experience eyestrain, headaches, squinting, and difficulty seeing clearly at night.

Most people with astigmatism can achieve clear, comfortable vision with appropriate correction. The best treatment approach depends on the severity of astigmatism.