Have you ever wondered why some people seem to have eyes that
don't look straight ahead? Maybe you've noticed that
sometimes their eyes go in different directions when they're
looking at an object or at you.
Let's find out why some eyes don't see straight and how
kids with this problem get help to fix it.
Why Are Some Eyes Not Straight?
Strabismus
(say: struh-
biz
-mus) is the term used for eyes that are not straight and do not
focus on the same object. Eyes can turn in (toward the nose) or out
(toward the ear) if the muscles that move the eyes do not work
right or if the eyes are not able to focus properly. Strabismus is
also sometimes called crossed eyes, when they turn in, or walleye,
when they turn out. It affects about four out of every 100 kids in
the United States.
You may have heard someone describe an eye that is not straight
as a lazy eye, but that is not what lazy eye means. It means that a
person's vision is weak or lazy. The medical term for lazy eye
is
amblyopia
(say: am-blee-
o
-pee-uh).
Strabismus and amblyopia are closely related and often (but not
always) occur together. Sometimes strabismus can cause amblyopia,
and sometimes it's the other way around with amblyopia causing
strabismus. When a kid has both conditions, it may be difficult to
say which came first.
The Eyes Have It!
So what happens when a kid has an eye that isn't straight?
To understand, first you need to know a little bit about the
eye
. The eye is like a camera, and the back of the eye, called the
retina
, is the film. Objects that your eyes see are projected onto the
retina, and these pictures are sent to the brain by way of nerve
signals. The brain detects these signals, puts them together to
form an image, and that's how you see. It's amazing that it
all happens so quickly - in a split second!
When a kid has strabismus, the eyes don't focus together on
the same object and each eye sends a different picture to the
brain. As a result, the brain sees two images (double vision) or
the object looks blurry.
The brain is really smart, and it doesn't like getting two
different pictures instead of one. To fix the problem, the brain
may ignore the picture coming from the one eye so it gets only one
clear image. By shutting off the bad eye in favor of the good one,
the bad eye gets weak or lazy (causing amblyopia), and without
treatment the bad eye might eventually even become blind.
What Will the Doctor Do?
Usually doctors diagnose strabismus when a baby or young kid has
a
regular checkup
. If a doctor or parent suspects a kid has strabismus, he or she
will be sent to a special eye doctor called an
ophthalmologist
(say: af-thuh-
mah
-luh-jist). The doctor will examine the kid's eyes and ask him
or her to read a chart on the wall or look into a microscope-type
machine. None of these tests hurt.
If the doctor thinks a kid has strabismus, there are different
ways to treat it. Some kids just need to wear
glasses
. Others may need surgery to straighten their eyes. Kids who have
amblyopia will need to wear a patch over the good eye to strengthen
the weaker one. For any kid who has strabismus or amblyopia,
starting treatment as soon as possible is the best way to improve
vision.
What's It Like?
Sometimes kids who have strabismus get teased. Like teasing for
any reason, this causes hurt feelings. If you know someone with
strabismus, be a friend and do not tease him or her.
And if you are the one who has strabismus, talk with a parent,
teacher, or counselor if you are being teased. The good news is
that this condition almost always can be treated, so someday you
can say so long to strabismus!
Reviewed by:
Sharon Lehman, MD
Date reviewed: December 2007
Originally reviewed by:
Alexander E. Pogrebniak, MD
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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