Astigmatism is like long- and short-sightedness in that it is a problem with how the eye focuses light; the horizontal and vertical lines of letters do not come into focus at the same time, causing the word to be distorted.
Mild astigmatism can be a normal finding in young children. As they grow up, the cornea changes shape and most children will lose their astigmatism.
Moderate to severe astigmatism affects the eye's ability to see clearly constantly and is likely to worsen over time, rather than a child 'growing out' of it. If light from an object cannot be focussed sharply on to the back of the eye then the child may develop a 'lazy' eye. This is also known as amblyopia.
Sometimes parents and teachers may notice, by the way a child acts, that their vision is impaired. Signs to watch out for include:
- Squinting or straining to see far away or up close
- Red or watering eyes
- Holds books and near materially very close
- Difficulty recognising similar looking letters or words
- Closing or blocking an eye to focus or concentrate
- Eye rubbing
- Blurred vision
Astigmatism frequently occurs in combination with long- and short-sightedness, creating long- sighted astigmatism or short-sighted astigmatism. In these instances, symptoms are then combined, and the overall effect on the vision is greater.
Treatment of hyperopia, or long-sightedness, often involves correction with glasses or contact lenses. As the eye's focusing ability is different when looking far away compared to looking up close, often different powers are needed for different viewing distances. In this instance, a bifocal or progressive lens is prescribed. Those who wear glasses do not become dependent on them and do not get worse through the use of spectacles.