What Is Amblyopia?

You probably know this childhood eye condition by its more common name, lazy eye. It happens when the vision of one of your child’s eyes doesn’t develop like it should

If it isn't treated, your child’s brain will learn to ignore the image that comes from that eye. That could harm her vision permanently.

What Causes It?

Amblyopia commonly starts when one eye has much better focus than the other. Sometimes, one is more farsighted or has lots of astigmatism, but the other doesn’t.

When your child's brain gets both a blurry image and a clear one, it starts to ignore the blurry one. If this goes on for months or years in a young child, vision in the blurry eye will get worse.

Sometimes a child’s eyes don’t line up like they should. One could turn in or out. The doctor will call this strabismus, and it can also lead to amblyopia. Kids who have it can’t focus their eyes together on an image, so they often see double.

If your child has it, her brain will ignore the image from the eye that isn’t aligned. Vision in that eye will get worse. It’s this misalignment that led to the term "lazy eye."

Some kids can’t see well out of one eye because something is blocking light from getting through. It could be a cataract or a small amount of blood or other material in the back of the eye.

How Is Amblyopia Diagnosed?

All children should be tested before they are school-age. Your child's doctor or the vision program at school will check to make sure that:

  • Nothing blocks the light coming into her eyes.
  • Both eyes see equally well.
  • Each eye moves like it should.

If there's any problem, the doctor or school nurse may suggest you take her to an eye specialist. If you feel something’s wrong with your child's vision -- even if nothing shows up at the vision check -- make an appointment with a pediatric eye doctor.

Some eye care experts say kids should get an eye exam at 6 months, 3 years, and then every year while they’re in school. Ask your doctor what’s right for your child.

If amblyopia runs in your family, your child is more likely to get it. Remember, you can’t tell just by looking at her if she has it. Early diagnosis and treatment are the keys to good results.


How Is It Treated?

The most common method is to force your child’s brain to start using the weak eye. First, the doctor will correct any underlying problems in that eye, like nearsightedness, farsightedness, or astigmatism. Most kids with amblyopia also need glasses to help their eyes focus. If a cataract is blocking light from her eye, the doctor may recommend surgery to remove it.

Then he’ll give her a patch to wear over her strong eye. At first, she’ll have a hard time seeing with just the weak eye. But it’s important that she wear the patch. Her vision will get better, though it might take weeks or months for that to happen. Follow the doctor's instructions carefully and bring your child in for scheduled visits so the doctor can see how the treatment is working.

After the doctor says her vision is back to normal, she won’t have to wear the patch all the time. But sometimes when kids go back to using both eyes, they lose some vision in the weak eye. If that happens, she might have to wear the patch again.

In mild cases of amblyopia, the doctor might suggest using an eye drop called atropine. It blurs the strong eye so your child won’t need to wear a patch.

If strabismus prevents her eyes from moving together like they should, your doctor might recommend surgery on her eye muscles. You can talk about what treatment is best for her.

What’s the Long-Term Outlook?

With early diagnosis and treatment, most children will gain vision. Amblyopia becomes much harder to treat after about 7-9 years of age, so make sure your child gets eye exams early on. And follow your doctor's advice about treatment, even when it’s hard. Most kids don’t want to wear an eye patch every day. Ask your doctor if atropine is an option for your child.

WebMD Medical Reference Reviewed by Dan Brennan, MD on October 15, 2019



American Optometric Association.

Mayo Clinic.

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