What is astigmatism?

Astigmatism is a problem with vision that is caused by the cornea or the lens of the eye not being perfectly curved. The result is blurred vision — mildly blurred for some people, severely blurred for others.

Eye check-ups can diagnose astigmatism, which can be treated with glasses, contact lenses or laser eye surgery.

What are the types of astigmatism?

There are 2 types of astigmatism:

• regular — where the cornea is curved more in 1 direction (say vertically) than the other (say horizontally)
• irregular — where the curvature of the cornea is uneven across the surface of the eye

What are the symptoms of astigmatism?

• blurred vision
• headaches
• tiredness
• difficulty seeing at night
• squinting
• eye strain, especially after concentrating for a long time
• a 'lazy eye' in children

Astigmatism involves poor focus at all distances. People who have astigmatism may also experience:

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

What causes astigmatism?

Astigmatism may be present at birth or develop with ageing, and may have a hereditary component. It can also result from eye disease or injury.

How is astigmatism diagnosed?

Your optometrist or ophthalmologist (specialist eye doctor) can diagnose astigmatism with an eye examination.

Testing may include:

• vision testing
• measurement of the curve of your corneas
• measurement of how well your eyes focus light

If you have any concerns about your eyesight, see your optometrist or talk to your doctor.

Astigmatism in children

Because astigmatism can be present from birth, it is important to have your child’s eyesight checked if you are concerned about their vision.

How is astigmatism treated?

For most people, astigmatism is a mild condition and does not need treatment beyond correction with glasses or contact lenses. More severe astigmatism may need treatment.

Treatments for astigmatism include:

• corrective glasses or contact lenses
• orthokeratology, which uses rigid contact lenses to reshape the cornea
• laser eye surgery, which reshapes the cornea