Lazy Eye (Amblyopia)
What is Amblyopia?
Amblyopia ('lazy eye') happens when the vision in one eye doesn't
develop properly in early childhood. You may not be able to notice it
easily in your child, but if it isn't treated it will become a permanent
visual problem.
What Causes Amblyopia?
Babies are able to see when they are born, but they have to learn how to
use their eyes. They have to learn how to focus, and then how to use
both eyes together. Our vision continues to develop until we are about 9
to 12 years old. After that, our eyesight is complete and can't be
easily changed.
However, sometimes the vision in one eye doesn't develop properly. This
may be caused by misaligned eyes (called strabismus) or because one eye
is out of focus compared with the other. When this happens, the brain
'shuts off' the eye that is out of focus, and the child depends only on
the better eye to see.
An eye disease such as a cataract or anything else that stops a clear
image from being focused inside the eye can cause amblyopia in children.
They may also inherit conditions from their parents that lead to
amblyopia.
How Is Amblyopia Diagnosed?
You may not be able to tell that your child has amblyopia. Many children
with the condition look completely normal and see well with their good
eye. If your child has an eye that turns in, out, or up, or if he or she
closes one eye (especially in bright sunlight), these are warning signs.
Some family doctors and pediatricians screen eyesight. There might also
be vision screening as part of a preschool checkup in your community. If
there is any doubt about your child's vision, they will refer you to an
eye doctor for more tests.
How Is Amblyopia Treated?
A child's vision is fully developed by age 9, so amblyopia must be
treated early in life, preferably before age 6. It is hard to reverse
amblyopia after that age. If it is treated early enough, amblyopia can
usually be reversed.
The Doctor's Role
Amblyopia is best treated by an ophthalmologist, often with the help of
an orthoptist. Treatment may involve glasses to correct blurred vision
or help straighten the eyes, and patching or blurring the vision of the
good eye to force the lazy eye to work. Surgery can be necessary as
well, to mechanically realign the eyes. Exercises or other types of
visual training are not effective in treating amblyopia.
The Parents' Role
If amblyopia isn't treated, it will lead to a lifetime of poor vision in
one eye. This puts your child at higher risk of vision loss if the
seeing eye is injured. As well, an eye with poor vision can become
misaligned (strabismus), which can affect your child's 3-D vision,
making certain activities difficult and even limiting some job
opportunities.
Parents play a vital role in making sure their child does not have this
disability. First, it is important to recognize any signs of a problem.
For example, it is not true that all babies are cross-eyed. If your
child is 6 months old and is still cross-eyed, you should see a doctor
as soon as possible. Second, you should never wait for your child to
'just grow out of' an eye problem. If you think something is wrong with
your child's eyesight, have it checked.
You will need to work with the doctors and others (such as teachers) to
ensure your child wears the glasses or patch as prescribed. You play a
key role in making sure your child has a lifetime of good eyesight. The
earlier the treatment is started, the sooner it is likely to be
successful.
© Copyright by the Canadian Ophthalmological Society