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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.
Like nearsightedness and farsightedness, astigmatism is a refractive error, meaning it is not an eye disease or eye health problem; it's simply a problem with how the eye focuses light. In an eye with astigmatism, light fails to come to a single focus on the retina to produce clear vision.