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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. Astigmatism is a refractive eye disorder caused by a misshapen cornea at the front of the eye. A normal cornea is spherical in shape, but some people are born with a more oblong shaped cornea that projects two points of light on to the retina at the back of the eye.yperopia (Far Sightedness). Hyperopia or far sightedness is a refractive eye disorder caused by a shorter than normal eyeball or a flatter than usual cornea. Light entering the unaided eye comes to focus behind the retina, thus casting a blur circle on the retina itself.