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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 is a common vision condition that happens when a person's cornea is not symmetrical. A normal cornea is round like a baseball. With astigmatism, the cornea curves more severely, like a football.