Astigmatism is a common vision condition that occurs when the cornea or the eye's natural lens is irregularly shaped. This asymmetric steepening prevents light from focusing properly on the retina (light-sensitive surface at the back of the eye), resulting in blurred or shadowed vision. Astigmatism can also cause discomfort and headaches.
Most people have astigmatism to some degree, usually present from birth, but mild astigmatism often doesn't affect the vision or require treatment. It often accompanies other vision conditions such as nearsightedness and farsightedness. A comprehensive exam will include a test for astigmatism. Treatment often includes eyeglasses or contact lenses, but corneal relaxing incisions, laser vision correction, and special implant lenses may be recommended.