Eye Conditions

Amblyopia

Amblyopia

Amblyopia is a condition that reduces vision in an eye that has not been used enough during early childhood. Double vision or blurred vision in one eye often causes the problem. About 2-4% of Americans have amblyopia. If not treated, an amblyopic eye may never develop good vision and may become functionally blind.

Amblyopia, also known as “lazy eye,” has many causes. Most often it results from a misalignment of a child’s eyes, such as crossed eyes. A difference in image quality between the two eyes (one eye has a clearer image than the other) can also lead to amblyopia. In either case, one eye becomes stronger and takes over the job of seeing while the other eye goes unused. If the condition continues, vision worsens in the unused eye. The eye becomes weaker and less capable of seeing. Early diagnosis and treatment can restore sight in the “lazy eye”. The earlier the treatment is started the better the chances of preventing or reversing the vision loss. Older children can sometimes be treated for amblyopia. For more information link to http://www.nei.nih.gov/ats3/ba...

What are the signs and symptoms?

  • Favoring one eye
  • Tilting the head
  • Drifting of an eye when the child is either tired, ill or in bright light
  • Any tendency to close one eye, especially in sunlight
  • Rubbing the eyes
  • Excessive blinking
  • Holding objects very close to the eyes

If parents notice any of these signs, the child should have a professional comprehensive eye examination. Be aware that children with amblyopia often show no obvious signs of trouble.

How do you treat Amblyopia?

In addition to treating amblyopia, the doctor must treat its underlying causes. These include misaligned eyes (strabismus) or unequal refractive errors (anisometropia).

  • Glasses are commonly prescribed to improve asymmetrical or different refractive errors or to correct for a misalignment of the eyes.
  • Surgery is performed on the eye muscles to help straighten the eyes if non-surgical means are unsuccessful. Surgery can help the eyes to work together better. Occasionally, it may be necessary to repeat the surgery.

To correct amblyopia, it is necessary to strengthen the vision in the poorer seeing eye. There are several ways to accomplish this.

  • Patching or covering the better seeing eye forces the “lazy” eye to work. The patient will wear the patch a variable amount of time depending upon improvement. This helps improve the vision.
  • Bangerter filters are translucent plastic sheets placed on the back surface of the spectacles. This filter slightly blurs the “good” eye. This is worn full time and is very well accepted by most patients.
  • Medication in the form of Atropine ophthalmic solution or ointment may be used daily or on a Saturday/Sunday schedule for a varying amount of time. Atropine blurs the vision in the “good” eye primarily up close, forcing the weaker eye to work.
  • Glasses or contact lenses may be used to blur the image in the stronger eye in an effort to get the “lazy” eye to work harder.

Patients will need to visit the doctor regularly to measure improvement in the amblyopic eye. The greatest and quickest improvements will tend to occur in the younger children. Treatment however may be recommended even in older children with successful outcomes.

Why is prompt treatment important?

The preschool years are critical ones in the development of a child’s vision. By the age of six to seven vision may be completely developed.

Without treatment for amblyopia, the unused eye will lose vision, possibly leading to a permanent partial loss of sight. With early detection and treatment before the age of three, the chance for restoring vision is excellent: about 95 percent. After the age of six, however, the chances of succeed decline. By the age of nine or 10, the chances of correcting amblyopia are limited, although some children in their teens have experienced an improvement of vision loss.

At first, a child may feel frustrated while being treated for amblyopia. Proper treatment, along with supportive parents who understand the problem and show patience toward the child, usually result in successfully restoring vision.

Reproduced with permission and thanks to PREVENT BLINDNESS AMERICA®.
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