Dr. M.J. Bazos,
Patient Handout
Amblyopia
What is amblyopia?
Amblyopia (say this: "am-blee-oh-pee-ah") is an
eye problem that causes poor vision in children. The problem starts when the
pathways of vision in the brain don't grow strong enough. Pathways are a little
like roads--they carry vision messages from eye to brain. Amblyopia is also
called "lazy eye."
What causes amblyopia?
All babies are born with poor eyesight. As
babies grow, their eyesight gets better. Good eyesight needs a clear, focused
image that is the same in both eyes. If the image isn't clear in one eye, or if
the image isn't the same in both eyes, the vision pathways won't develop right.
In fact, the pathways may actually get worse.
Anything that happens to blur the vision or
cause the eyes to be crossed during childhood may cause amblyopia. For example,
the image might be different in both eyes if the child has strabismus.
Strabismus (also called "crossed eyes") causes the eyes to not focus the same.
Children who need glasses to see better, or have cataracts, a droopy eyelid, or
crossed or wandering eyes may also get amblyopia. About 5% of children have
amblyopia.
How is amblyopia
treated?
Because there are several causes of amblyopia,
the treatment must match the problem. Glasses fix some problems. Surgery may be
needed for cataracts, droopy eyelids or crossed eyes. After the cause of the
amblyopia is found, the child will need to use the weaker eye most of the time,
so it will get stronger. To make the child use the weaker eye, a patch can be
put over the stronger eye. Sometimes, eye drops or special glasses are used to
blur the vision in the stronger eye. This makes the weaker eye become stronger.
Patches may be used all day or part of the day, depending on the child's age and
vision.
The treatment usually lasts until vision is
normal, or until vision stops getting better. For most children, this takes
several weeks. A few children need to use eye patches until they are 8 to 10
years old.
Why is early treatment
important?
The vision pathways in the brain must become
strong early, when children are very young. The first few years of life are the
most important for eyesight. After a child is 8 to 10, the brain's vision system
is complete. It can't develop anymore. If the amblyopia hasn't been treated by
this age, the child will have poor vision for life. It won't be possible to fix
it with glasses, patching or any other treatment.
There's a small chance that using an eye patch
for too long can hurt the strong eye. For this reason, children who are wearing
eye patches should see their doctor often during the treatment.