Strabismus is a condition where the eyes are not properly aligned with each other. Normally, our eyes fixate to focus on the same object, and move in sync to focus on another. Like its common name, cross-eyed, an often visible misalignment of the eyes occurs causing one eye to focus in one direction and the other to focus elsewhere. Both eyes are unable to fixate simultaneously. Many babies are born with some form of misalignment, but usually outgrow it by 6-12 months of age.
The 3 most common types of Strabismus are:
- Esotropia – Commonly known as having ‘crossed eyes’. One eye turns inward and one remains straight ahead. This typically appears at birth.
- Exotropia – Also known as ‘walleye’ where one eye turns outward, away from the nose and one remains straight ahead.
- Hypertropia – Also known as Vertical Deviation and is characterized by one eye turning upwards, towards your eyebrow. This is a far less common type of Strabismus.
If you think your child may have strabismus, please book them in for an eye exam.
Causes of Strabismus
This condition, including it’s common types, are usually present at birth; alternatively, early onset symptoms arrive in young children and can be visibly noticeable. It is generally known that weakness in the eye muscles causes the eyes to look in separate directions. Although Strabismus has no known cause, it does tend to run in families and can be classified as hereditary.
Some forms of Strabismus can develop as a side effect to other illnesses and genetic disorders such as down syndrome, a traumatic head injury, brain tumour or stroke.
Signs and Symptoms
When the eyes are oriented in two different directions, they produce two different images. The brain is then tasked with either accepting both images, resulting in double vision, or favouring one eye over the other. This can result in poor vision and lack of depth perception causes the following symptoms:
- Eyes can cannot look in the same direction at the same time. Can be obvious, or slight
- The eyes do not move in unison
- Squinting one eye to see out of another
- Poor depth perception causing tripping and bumping into things
- Turning or tilting the head to focus
Strabismus is typically treated with the combination of specially designed eye glasses, vision therapy and surgery depending on the severity or reason of misalignment. Surgery can be performed in children younger than one year.
Vision therapy is a popular option for most causes of strabismus. This consists of regular eye exercises to teach the muscles to realign with one another. Usually vision therapy is coupled with the specially designed corrective lenses to aid in recovery.