Astigmatism

Introduction 

Astigmatism is a common and usually minor eye condition that causes blurred or distorted vision.

It occurs when the cornea or lens isn't a perfectly curved shape. Many people who wear glasses have some degree of astigmatism.

Astigmatism belongs to a group of related eye conditions known as refractive errors. Other common refractive errors include:

• short-sightedness (myopia)
• long-sightedness (hypermetropia)

If you have astigmatism, it's likely you'll also have one of these conditions.

Left untreated, astigmatism can cause headaches, eye strain and fatigue (tiredness), particularly after doing tasks that involve focusing on something for long periods, such as reading or using a computer.

What causes astigmatism?

Astigmatism is usually the result of an irregular-shaped cornea or lens. The cornea is the transparent layer of tissue at the front of the eye.

The cornea should be regularly curved like the surface of a football, but in cases of astigmatism it has an irregular curve, more like the shape of a rugby ball. This means that light rays entering the eye aren't focused properly, creating a blurred image.read more