Amblyopia/ Lazy Eye

Amblyopia is the term used for a condition in children where one eye has poorer vision than the other. Treatment of this condition is important to ensure the correct development of vision. If left untreated, the vision will only get poorer in the effected eye as the child gets older – and could eventually lead to vision loss of one eye.

The Cause of Amblyopia

There are different types, and therefore different causes, of Amblyopia or ‘lazy eye’. In most cases it usually starts when one eye has the ability to focus better than the other. This can be down to factors such as one eye being nearsighted, or having a great level of astigmatism, whilst the other eye can see clearly. The brain realises that there is one clear image and one unfocused image from the eyes, which is why it starts to ignore the blurry image. When the brain has done this for months (or longer) the sight of the blurry eye will become worse, and can even result in changes in the alignment of the eyes, where one eye becomes ‘lazy’ and turns either outwards or inwards.

Other forms of lazy eye might prevent the child‘s eyes from focusing together on an image, which results in double vision. The brain will again ignore the image from one eye resulting in deteriorating vision of that eye. Other causes of one eye seeing less well than the other could include cataracts or material in the eye.

Treatment of Amblyopia

Usually treatment involves forcing the brain to make use of the worse eye. A patch is put over the good eye, which can make it hard for the child to see at first. After weeks or even months vision should start to improve in the bad eye. Once vision has returned to normal levels then the patch will no longer need to be worn. Alternatively the doctor may prescribe a certain type of eye drop that makes it impossible for the good eye to focus close-up, again making the bad eye work harder.

If the cause of a child’s Amblyopia is down to something blocking the light in the eye then surgery may be required to remove this. Glasses or contact lenses may also be used to correct the focus of eyes which differ greatly.