Table of Contents - This Web Page

• What is Amblyopia?
• What Causes Amblyopia?
• What Are The Signs of Amblyopia?
• Making The Diagnosis
• Treatment
• What if My Child Refuses to Wear the Patch?

• What Is Amblyopia?

  Amblyopia refers to reduced vision in one or both eyes caused by visual deprivation in childhood.  That is, even with proper eyeglasses, an eye with amblyopia does not see well!  It is often reversible with the appropriate treatment.  The term "lazy eye" is often used to describe amblyopia.
  
  Amblyopia results from actual atrophy of the visual pathways in the brain that allow an individual eye to "see."  That is, because of improper stimulation of the involved eye, the portion of the brain serving that eye does not develop properly.
  
  Amblyopia affects approximately 2-5% of all children.

• What Causes Amblyopia?

  The causes of amblyopia are varied and include:
  

  • Strabismus ("crossed-eyes") - this refers to any misalignment of the eyes.   When the eyes are not aligned, the child's brain will often select one eye to view the world while the other will be "shut off" or "suppressed".   The eye that is habitually deviated or crossed is at risk for developing amblyopia.
  • Anisometropia - this refers to an unequal eyeglass prescription between the eyes.   If eyeglasses are not worn, then the eye that receives the more blurred images (the eye with the higher eyeglass prescription) is at risk for developing amblyopia.
  • Visual deprivation - any ocular disease that blocks the visual images from reaching the back surface of the eye (retina) can cause amblyopia.  Examples include congenital cataracts, corneal opacities or droopy eyelids (ptosis).  Even if the underlying disease is corrected with the appropriate surgery, a significant amblyopia may persist.

  The extent of visual loss due to amblyopia ranges from mild to severe.

• What are the Signs of Amblyopia?

  
  

  Unless an obvious abnormality is present (e.g. crossing of the eyes, a droopy eyelid or a dense cataract), amblyopia may have no obvious signs.  When only one eye is affected, a young child will not usually complain of blurred vision.
  Fortunately, children undergo vision screening periodically at their pediatrician's office and at school in an effort to detect amblyopia.

• Making the Diagnosis...

  The pediatric ophthalmologist performs all of the necessary tests to confirm whether your child has amblyopia.
  
  Vision testing is accomplished with methods appropriate for your child's age.
  
  An examination with eye drops that dilate the pupils is performed. A refraction, or measurement of how nearsighted, farsighted and how much astigmatism is present, is performed for each eye. (Astigmatism means the eye is shaped more like a football than a basketball.)  This permits an evaluation of the internal ocular structures and allows a determination whether or not there is a need for eyeglasses.

• Treatment

  The key to successful treatment of amblyopia, is early detection.  See Vision Screening If the amblyopia is caused by a strabismus (misaligned eyes), patching therapy, and sometimes glasses,are generally recommended.
  
  If there is a significant difference in refraction between the two eyes (anisometropia), an anisometropic amblyopia is present. Appropriate glasses are prescribed in conjunction with patching therapy.
  
  If there is a cataract or other ocular abnormality present, the appropriate surgery may be recommended.
  
  If the vision remains, poor despite treating any underlying causes, an appropriate eye patch will be recommended to be worn over the stronger eye.  This will force the brain to use the eye with amblyopi, or "lazy" eye.  After wearing the patch for the prescribed duration of time, the amblyopia will often improve.

  Eye patch worn over this child's right eye to improve amblyopia in the left eye.

  For achieving the best results in amblyopia therapy, total visual deprivation of the stronger eye is recommended.  For this reason, eye patches that adhere to the skin around the eye socket are most the most effective.  Patients who are unable, or unwilling, to wear a "sticky patch" may try a patch worn over the glasses. Special plastic patches worn unobtrusively on the inside of the glasses, called Bangeter Foils, may also be effective, especially in older children who do not want to wear an obvious patch in school.

  Sometimes, particularly if a child is resistant to tradtional patching regimens, "atropine" dilating eyedrops may be helpful.  Atropine is instilled onto the dominant eye, creating a blurring effect, which may allow the child to switch fixation and use the fellow eye with amblyopia - thus "patching without a patch."
  
  The pediatric ophthalmologist will prescribe the appropriate number of hours that the patch should be worn each day.  While undergoing patching therapy, it is critical that your child return for a vision check at the recommended time intervals!  This is to safeguard against the development of amblyopia in the eye being patched.
  
  Generally, the younger the child, the faster the desired results are obtained with amblyopia therapy.  After about the age eight or nine years, improvement in vision with patching therapy becomes more difficult, but not impossible.

• What if My Child Refuses to Wear the Patch?

  It is common that children with amblyopia will refuse to wear the patch and remove it when left unsupervised.
  
  Patching should commence during a time when you can devote all of your attention to your child (ie, on a weekend).  Typically, the first few days are the most difficult.   Keep your child occupied with games, computer, or television when wearing the patch.  If your child removes the patch, then promptly replace it. Be firm.  When all else fails, bribery may sometimes be necessary.
  
  In some younger children, the use of mittens or socks over the hands taped to the wrists may be required.  Sometimes, elbow splints are needed to prevent a child from removing the patch.
  
  

• Can surgery correct amblyopia?

  No!

• If not treated, can my child outgrow amblyopia?

  No! Uncorrected amblyopia leads to permanent vision loss!