What is Astigmatism?
It is a refractive error, not an eye health problem. It is an imperfection in the curvature of your cornea. The problem with astigmatism is that the eye does not focus light evenly onto the retina.

Astigmatism can either be myopic, hyperopic or mixed. Myopic astigmatism is a combination of astigmatism and myopia, or nearsightedness. It is a condition where the light focuses before it reaches the eye. Hyperopic astigmatism, on the other hand, is a combination of astigmatism and hyperopia, or farsightedness. And in case one principal meridian of the eye is nearsighted and the other is farsighted, it is called mixed astigmatism.

Other types of astigmatism are corneal and lenticular. In corneal astigmatism, the cornea has an irregular shape while in lenticular astigmatism, the lens has an irregular shape.

Who is at Risk for Astigmatism?
Children and adult are at risk for astigmatism. It is essential to undergo eye examinations as early as possible especially children aged 5 to 17. But there are also people who are born with this condition particularly low birth weight or premature babies.

What Causes Astigmatism?
The exact cause of astigmatism is unknown but it happens when the shape of the cornea or the lens is irregular. The chance of developing it may be higher if you have a family history of astigmatism, undergone an eye injury or surgery, and have excessive nearsightedness or farsightedness.

What are the Symptoms of Astigmatism?
Symptoms of astigmatism include blurred vision, headache, eyestrain, squinting, difficulty seeing at night, and photophobia.

How is Astigmatism Treated?
Astigmatism may be diagnosed by the following tools: visual acuity test, astigmatic dial, keratometer, and keratoscope. It can be corrected with glasses, contact lenses and laser eye surgery.

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