A few things can cause astigmatism. Astigmatism can be genetic, so you can inherit the problem. It can be caused by a disease. It can also be caused by an injury, resulting in scarring of the cornea. In most cases, astigmatism can be corrected either by glasses, or surgery. You can find more information here: http://www.allaboutvision.com/conditions/astigmatism.htm
