What Is Astigmatism?

Answer 1

Astigmatism is a type of refractive error in which the eye cannot focus light evenly on the retina. This causes distorted or blurred vision at all distances. Other symptoms can include eyestrain, headaches, and trouble driving at night. The cause of astigmatism is unclear. It is believed to be partly related to genetic factors. It can be diagnosed by eye exam. There are three treatments:

• Glasses are the simplest.
• Contact lenses can provide a wider field of vision.
• Refractive surgery will change the shape of the eye permanently.

Types of astigmatism       Divided by the surface of the cornea

• Regular astigmatism
• Irregular astigmatism

      Divided by the focus of images

• Simple astigmatism

1. Simple hyperopic astigmatism
2. Simple myopic astigmatism

• Compound astigmatism

1. Compound hyperopic astigmatism
2. Compound myopic astigmatism

• Mixed astigmatism

Keywords: astigmatism; hyperopic astigmatism; myopic astigmatism.