What is astigmatism?

Astigmatism is a very common focusing problem of the eyes. Many people who wear glasses have some degree of astigmatism. It occurs when the cornea or lens of the eye isn’t a perfectly rounded shape.

In people without astigmatism, the cornea and lens are curved by the same amount in all directions, like the surface of a football. In cases of astigmatism the eye is more steeply curved in one direction than the other – more like the shape of a rugby ball. This means that light entering the eye isn’t focused properly, creating a blurred image. Astigmatism can easily be corrected with glasses or contact lenses.

You can also have an irregular astigmatism, which is less common and occurs when the cornea is curved by a different amount in multiple directions or in different areas of the cornea.  An irregular astigmatism may be caused by an eye condition or injury to the cornea, and glasses may not be able to correct your vision fully.

For further information about astigmatism and other eye conditions contact our Helpline:

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