Strabismus (Crossed Eyes) and Amblyopia (Lazy Eyes)

Approximately 2% of American children have amblyopia and 3-5% have strabismus.

Strabismus (Crossed Eyes) and Amblyopia (Lazy Eyes) Optometrist
Specialty Vision

What is strabismus?

Strabismus is the medical term for crossed eyes which occurs when the eyes are not aligned. One or both of the eyes could be turned inwards, outwards, upwards or downwards and both eyes are not focused on the same target. It is common for this to occur when a person is very farsighted or has poor eye muscle control. The wandering eye may be a constant phenomenon or it manifests when the person is tired, ill or has done a lot of viewing up close such as reading. If left untreated, strabismus could get worse.

Risk Factors:

  • Family history
  • Refractive error - if someone is very farsighted and has not received the proper prescription for an optical correction, such as glasses
  • Various health conditions such as down syndrome, cerebral palsy or after a stroke or head injury

What are some signs of strabismus?

  • Wandering eyes
  • Eyes do not move in sync
  • Tilted head
  • Poor depth perception
  • Frequent blinking or squinting
  • Double vision

It is important to keep in mind that while strabismus may be noticeable in large angle strabismus, it could also easily be missed if it's intermittent, alternating or a small angle strabismus.


How is strabismus treated?

There are different treatment options, depending on the cause and diagnosis. Sometimes one or more methods are used for the same patient: 

  • Glasses or contact lenses - at times this is the only necessary treatment
  • Prisms - special types of lenses which bend the light in a unique way
  • Vision therapy - various exercises can be used to train the eyes to focus and coordinate properly with each other and with the brain

Often these methods of treatment will suffice, but there are cases where eye muscle surgery will be recommended. It is advisable to first try the non-invasive treatment techniques above before deciding if to operate.

What is amblyopia?

What is amblyopia?

Lazy eye, known medically as amblyopia, is the main cause of loss of vision in children in one eye. Amblyopia is a condition that occurs when the eyes are not working together properly as a team along with the brain. Each eye receives its own image which is not coordinated with the other. So in order to cope, the brain shuts off communication with one eye, nicknamed the ‘lazy eye’ by suppressing it. Clear vision is achieved by the other, stronger eye as the lazy eye cannot achieve 20/20 vision, even with an optical correction. 

Risk Factors

Some children are more prone to developing a lazy eye. The risk factors include:

  • Family history
  • Premature birth or an infant who is born with a low weight
  • Developmental delay
How is amblyopia treated?

How is amblyopia treated?

Scientific studies have proven that eye patching alone is no longer the recommended method of treating a lazy eye.

The following methods of treatment are generally offered, sometimes just one method will suffice, while other cases require a combination of various treatment methods:

  • Glasses or contact lenses - sometimes this is the only method required
  • Vision therapy - various exercises are used to train the eyes to work properly together and to communicate with the brain; studies show that treating with vision therapy could reduce the need for patching the stronger eye
  • Closing one eye - it’s now been proven that patching the stronger eye for a shorter amount of time while the patient is performing cognitive activities using the lazy eye yields similar results than if the eye is occluded for long periods of time

Common Questions

Strabismus typically precedes amblyopia. Strabismus refers to the misalignment of the eyes, where one or both eyes turn inward, outward, upward, or downward. If untreated, the brain might start ignoring the visual input from the misaligned eye to avoid double vision, leading to amblyopia, commonly known as "lazy eye." It's essential to see an eye doctor early if strabismus is suspected to prevent the onset of amblyopia.
Yes, you can have amblyopia without strabismus. While strabismus is a common cause of amblyopia, other factors, like a significant difference in refractive error between the eyes or a visual obstruction in one eye, can also lead to amblyopia. Regular check-ups with an optometrist can help in early detection and treatment.
Strabismus is considered abnormal at any age, but it's most commonly identified in children between the ages of 1 and 4. While newborns might occasionally have misaligned eyes, they typically outgrow it by 3-4 months. If a child has noticeable eye misalignment beyond this age, it's essential to consult an eye doctor for a functional eye exam and potential vision therapy.
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Strabismus, commonly known as crossed eyes, is a condition where the eyes are misaligned and not focused on the same target. It can result from farsightedness or poor eye muscle control. Symptoms include wandering eyes, lack of eye coordination, tilted head, and double vision. Strabismus can be hereditary or associated with certain health conditions. Treatment options include glasses, prisms, vision therapy exercises, and in some cases, eye muscle surgery. Amblyopia, or lazy eye, is a condition where the brain suppresses communication with one eye, leading to vision loss. Risk factors for amblyopia include family history, premature birth, and developmental delays. Treatment for amblyopia typically involves glasses, vision therapy, and patching the stronger eye for shorter periods while using the lazy eye.