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However, in some cases it can cause troublesome vision distortion. Here are the most common signs and symptoms of astigmatism: 1  Blurring or distortion of images at all distances. 2  Headache. 3  Fatigue. 4  Squinting. 5  Eye discomfort or irritation. 6  Difficulty seeing at night.
You can tell whether you have astigmatism by looking at your eye prescription. The box 'Cyl' will show the power you need to correct astigmatism, if you have one. Axis tells the manufacturer of the glasses or contact lenses where the astigmatism is and where the power should be to correct it. Causes of Astigmatism. Astigmatism is caused when the cornea of the eye becomes oblong or oval rather than spherical. A cornea which has astigmatism has two curves, a flat curve and a steep curve so light is focused at two points instead of more clearly at just one point.