Astigmatism; etiology, classification and management

Astigmatism is a common vision condition that occurs when the curvature of the cornea (the clear, dome-shaped structure at the front of the eye) is irregular, causing light to focus improperly on the retina (the light-sensitive layer at the back of the eye). This can result in distorted or blurred vision, especially at night or when looking at objects in the distance.

Astigmatism is usually inherited and is present at birth, but it can also develop after an injury or surgery to the eye. It can occur in combination with other vision conditions, such as myopia (nearsightedness) and hyperopia (farsightedness).

Symptoms of astigmatism include blurred vision, eyestrain or headache when reading or doing close work, and the need to squint to see clearly. It can also cause problems with driving at night, as it can make it harder to see clearly when looking at headlights or other bright lights.

Astigmatism is usually diagnosed during a comprehensive eye exam, which includes a series of tests to assess visual acuity and the health of the eyes. It can be corrected with eyeglasses, contact lenses, or refractive surgery, such as LASIK (laser-assisted in situ keratomileusis).

In conclusion, astigmatism is a common vision condition that occurs when the curvature of the cornea is irregular, causing light to focus improperly on the retina. It can cause blurred vision, eyestrain, and other symptoms and can be corrected with eyeglasses, contact lenses, or refractive surgery.


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