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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.
Astigmatism usually occurs when the front surface of your eye, the cornea, has an irregular curvature. Astigmatism is one of a group of eye conditions known as refractive errors and these errors cause a disturbance in the way that light rays are focused within your eye.stigmatism usually occurs when the front surface of your eye, the cornea, has an irregular curvature. Astigmatism is one of a group of eye conditions known as refractive errors and these errors cause a disturbance in the way that light rays are focused within your eye.