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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.
Some cases of astigmatism are caused by problems in the lens of the eye. Minor variations in the curvature of the lens can produce minor degrees of astigmatism (lenticular astigmatism). In these patients, the cornea is usually normal in shape. Infants, as a group, have the least amount of astigmatism.