Astigmatism
- Reviewed by Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing
What is astigmatism?
Astigmatism means that the cornea of the eye has an irregular shape, causing vision problems. The cornea is the clear covering over the lens and the iris. It protects these structures and helps to transmit light through the eye. The cornea is normally spherical, although in people with astigmatism, it may be shaped like a football or oval. This causes light to scatter instead of focus on a single point as it passes through the cornea, resulting in blurred vision.
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About the Reviewer
Howard E. LeWine, MD, Chief Medical Editor, Harvard Health Publishing; Editorial Advisory Board Member, Harvard Health Publishing
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