What is a stigma in the eye?

Astigmatism refers to an irregular curvature of the cornea, the front surface of the eye. This curvature affects the ability of the eye to focus, and can result in distortion or blurring of vision, both near and far, as well as headaches, squinting and eye discomfort. Astigmatism is very common and can be corrected by wearing glasses or contact lenses. Laser eye surgery can also reshape the cornea, but is usually performed only in adults, since vision may continue to change throughout adolescence.