Children's astigmatism

The medical term is…

Astigmatism

Intro

Astigmatism (pronounced ah-stig-mah-tism) is a common and treatable eye condition. The front surface of a normal eye is round like a football. But if you have astigmatism the eye is shaped more like an oval rugby ball, making your vision blurred. A person with astigmatism will usually also be short or long sighted.

People can be born with astigmatism or it can develop later in life.  It can be treated by wearing glasses or contact lenses, or by having laser surgery.

How you see the world

Many of us have a little astigmatism and our sight is unaffected. If the astigmatism is more severe you might notice:

  • blurring and distortion of near or far-away objects
  • headaches when trying to focus
  • tired eyes
 
 

What does that word mean?  

In Greek ‘a-‘ means ‘without’ and ‘stigma’ means ‘point’. So together they mean ‘without point’ because the eye can’t focus clearly on a single point.

 

 
Light rays are focused to more than one point in the eye if you have astigmatism

Light rays are focused to more than one point in the eye if you have astigmatism

How the world sees you

Your condition is not visible to other people, though you might have to wear glasses or contact lenses.

Why did I get it?

The exact cause is usually unknown although genes inherited from your parents can play a part. Sometimes astigmatism can develop after an eye injury, surgery or because of an eye disease. Astigmatism is not caused by reading in bad light, using a computer or watching too much television.

What causes it?

The cornea (‘window’) at the front of your eye and the lens inside i, work together to create an image that is in focus. The cornea and the lens must form a smooth round shape, so that light passing through becomes sharply focused at the back of the eye, allowing you to see clearly. 

Astigmatism occurs when the shape of the cornea or lens is not round (like a football) but oval (like a rugby ball). This changes the path of light so that the image formed at the back of the eye is not sharply focused.

How can the doctor tell

If you have astigmatism, an eye specialist can examine your eye to detect the problem. They might do a test called retinoscopy (refraction or sight test) to measure the eyes’ focusing power, or use a keratometer or keratoscope machine, which shine a light at the eye and measure the distortion of light reflected back by the cornea.

 
 
  • Astigmatism is extremely common and usually easily treated
  • It can be corrected by glasses or contact lenses
  • Laser surgery can correct astigmatism once the eye is fully grown
 

Getting it sorted

Glasses and contact lenses can be used to correct vision. Mild astigmatism might not require treatment unless you do something that puts demands on the eyes, such as using a computer screen for long periods.

If the front surface of the cornea is uneven, hard contact lenses can help create a smooth, even surface. Normal soft contact lenses don’t always work well as they mould to the uneven surface of the cornea, but special “toric” soft lenses can be used. There is also refractive surgery where the cornea is reshaped by laser, small incisions (cuts) or implants, but this is usually only suitable for adults, when the eye has finished growing.

An optometrist can discuss which treatment best suits your lifestyle.

If you have astigmatism or any other eye problems, you should get your eyes checked regularly.

If you have astigmatism or any other eye problems, you should get your eyes checked regularly.

Stopping it before it starts

Astigmatism cannot be prevented.

Moorfields Eye Hospital NHS Foundation Trust
City Road, London EC1V 2PD
Phone: 020 7253 3411 
www.moorfields.nhs.uk

Moorfields Direct Telephone Helpline
Phone: 020 7566 2345
Monday to Friday 09.00 to 16.30 for further information and advice. 

 

Date Published: April 2011 Date for review: April 2013
Author: Moorfields Paediatric Information Group 

 

 

Last updated: 20th November 2017