Understanding Amblyopia (Lazy Eye)

Amblyopia, or ‘lazy eye’, is poor vision in an eye that does not develop normally during childhood. Vision loss occurs because pathways between the brain and eye are not properly stimulated during development. As a result, the brain does learn not to see from one eye and can lead to impaired vision if left untreated.

Types of Amblyopia

There are several different causes of amblyopia, all of which can result in vision loss:

  • Refractive- large or unequal amount of refractive error between the two eyes
  • Strabismic- misalignment between the two eyes causing them to drift outwards or inwards
  • Deprivation- the eye is ‘deprived’ of vision by conditions that do not allow light to enter the eye including cataracts and droopy eyelids


A child with amblyopia may not complain of blurry vision because of the way the brain has learned to perceive images during development. Additionally, the ‘lazy eye’ may not appear any different than the normal eye. Vision screening is often the only way amblyopia is detected.

Some symptoms of amblyopia may include:

  • An eye that drifts outward or inward
  • Eyes that appear not to work together
  • Poor depth perception

Although amblyopia usually affects one eye, it is possible to develop the condition in both eyes.


One of the most important treatments for amblyopia is correction of any underlying refractive errors with glasses or contact lenses. Other treatments include stimulating the weaker eye by blurring the better-seeing eye with patching or eye drops. Surgery may be needed to repair strabismus or correct conditions that may block vision, including cataracts.

What To Expect During Your Visit

An evaluation for amblyopia will typically last about 1-2 hours from the time you enter the exam room. Your child’s entire medical, ocular, family, and social history will be reviewed as well as any current medications. The examination will start with a measurement of your child’s vision. The pupils, eye muscles, side vision, color vision, and stereoacuity will also be tested. Prisms also may be used to measure any misalignment of the eyes.

Your child will then be given eye drops that will dilate their pupils. These drops take about 30 minutes to work. They may make the eyes light sensitive and difficult to focus, especially up close, for several hours.

The doctor will then shine several lights into your child’s eyes. These instruments allow for a thorough examination of the various parts that make up both the outside and inside the eye, as well as check for any problems that may require prescription glasses.

Additional testing, including specialized imaging, may also be required to further evaluate any abnormal findings on the exam. The results of your child’s exam will then be reviewed at the completion of the visit.