Amblyopia or Lazy Eye

Amblyopia, commonly known as a lazy eye, refers to the condition in which the brain 'turns off' or ignores the input from one eye. However, in some complex cases amblyopia can happen in both eyes.

There are a number of reasons this occurs. In a normal vision system, the brain receives an image from each eye and it merges these two images together to form one complex image. The two images are slightly different and slightly apart, and this difference creates 3D vision. 

But, if the two images are very different in size (aniseikonia) and/or too far apart (strabismus), the brain can't merge the two - resulting in double vision. 

Because the brain simply cannot process doubled vision, it will 'turn off' the signal from one eye - usually the non-dominant one. Once turned off, the eye will not function properly and hence the term 'lazy' eye.

If this happens during the critical stages of growth and development of the eye (from birth to 8-12 years old) this can cause permanent vision loss in the lazy eye. 

For this reason, it is important to pick up any vision issues as early as possible and intervene promptly with treatment.

Traditional treatments for amblyopia consist of turning off the good eye and forcing the lazy eye to work, and this is known as penalisation therapy. This is often in the form of putting an eye drop in or an eye patch over the strong eye and forcing the lazy eye to work. 

Newer research indicates that rather than promoting one eye over the other, encouraging the two eyes to work better together is more effective at resolving amblyopia. This is known as dichoptic or binocular therapy. 


  • An effective dichoptic treatment for aniseikonia-related amblyopia is specialised aniseikonic lenses, called Shaw Lenses. 
  • An effective dichoptic treatment option for strabismus-related amblyopia is vision therapy.

Often, these two treatment options will be used in conjunction with each other and/or with the traditional penalisation treatments. 

Every case of amblyopia is different. To speak to one of our Optometrists about a tailored approach to yours, or your child's case, make an appointment here.