Exotropia: Symptoms, Causes, Treatment

What are the symptoms of exotropia?

Exotropia is a type of strabismus (eye misalignment) where one or both eyes turn outward. The symptoms of exotropia can vary depending on the severity and frequency of the eye turning. Common symptoms include:

Outward eye deviation: One eye or both eyes may turn outward, especially when focusing on distant objects.
Intermittent or constant eye misalignment: The eye misalignment may be occasional (intermittent exotropia) or constant (constant exotropia).
Double vision: Some individuals may experience double vision (diplopia) when the eyes are misaligned.
Poor depth perception: Exotropia can affect depth perception, making it challenging to judge distances accurately.
Squinting or closing one eye: Individuals may squint or close one eye to reduce double vision or improve focus.
Head tilting: Tilting the head to one side may help align the eyes and reduce double vision.
Eye strain or fatigue: Straining to align the eyes can lead to eye discomfort or fatigue, especially after prolonged use.
Difficulty with near vision tasks: Exotropia can make it challenging to focus on close-up tasks like reading or writing.

It’s important to note that some people with exotropia may not exhibit noticeable symptoms, especially if the eye turning is subtle or intermittent. If you suspect you or someone you know has exotropia, it’s essential to consult an eye care professional for a comprehensive eye examination and appropriate management.

What are the causes of exotropia?

Exotropia can have several underlying causes, and the exact cause can vary from person to person. Some common causes and risk factors for exotropia include:

Muscle imbalance: Exotropia can occur due to an imbalance in the muscles that control eye movement. Weakness or paralysis of the muscles that turn the eye inward (medial rectus muscles) or overaction of the muscles that turn the eye outward (lateral rectus muscles) can lead to outward eye deviation.
Refractive errors: Uncorrected farsightedness (hyperopia) is a common risk factor for exotropia, especially in children. Farsightedness can cause the eyes to exert more effort to focus, leading to eye strain and potentially misalignment.
Eye trauma or injury: Damage to the eye muscles or nerves from trauma or injury can result in exotropia.
Neurological conditions: Certain neurological conditions, such as cerebral palsy, Down syndrome, or brain tumors, can affect the nerves and muscles that control eye movement, leading to exotropia.
Genetics: Exotropia can sometimes run in families, suggesting a genetic component to the condition.
Amblyopia (lazy eye): Amblyopia can occur when one eye has significantly better vision than the other, leading to a preference for the better-seeing eye and potential misalignment of the other eye.
Environmental factors: Prolonged periods of close work, such as reading or using electronic devices, can strain the eyes and potentially contribute to the development of exotropia, especially in individuals predisposed to the condition.
Systemic conditions: Certain systemic conditions, such as thyroid disorders or diabetes, can affect eye muscles and nerves, increasing the risk of exotropia.

It’s essential to consult an eye care professional for a comprehensive evaluation if you or someone you know has symptoms of exotropia. Treatment options can vary depending on the underlying cause and severity of the condition.

How is the diagnosis of exotropia made?

The diagnosis of exotropia is typically made through a comprehensive eye examination by an eye care professional. The diagnostic process may include the following steps:

Medical history: The eye care professional will inquire about the patient’s medical history, including any symptoms of eye misalignment, vision problems, or underlying health conditions.
Visual acuity test: This test measures the clarity of vision in each eye using an eye chart. It helps determine if there are any refractive errors (such as nearsightedness, farsightedness, or astigmatism) that could contribute to the exotropia.
Cover test: During a cover test, the eye care professional will cover one eye at a time to observe how each eye moves and if there is any deviation when one eye is covered and then uncovered.
Ocular motility (eye movement) testing: This test evaluates the range and coordination of eye movements to assess any muscle imbalance or weakness that could be causing the exotropia.
Binocular vision assessment: Tests such as the stereopsis (depth perception) test may be conducted to evaluate how well the eyes work together as a team.
Refraction test: If refractive error is suspected, a refraction test may be performed to determine the appropriate prescription for corrective lenses.
Dilation of the pupils: In some cases, the eye care professional may dilate the pupils using eye drops to get a better view of the back of the eye and to check for any other eye conditions that may be present.
Additional testing: Depending on the individual case, additional testing such as imaging studies or neurological evaluations may be recommended to rule out other underlying causes of the exotropia.

What is the treatment for exotropia?

The treatment for exotropia depends on several factors, including the severity of the eye misalignment, the underlying cause, the patient’s age, and their overall eye health. Treatment options for exotropia may include:

Glasses: If refractive errors (such as farsightedness) are contributing to the exotropia, prescription glasses may be prescribed to correct the refractive error and help align the eyes.
Prism lenses: Prism lenses can be added to glasses to help align the eyes and reduce double vision in some cases of exotropia.
Vision therapy: Vision therapy involves a series of exercises and activities designed to improve eye coordination and strengthen the eye muscles. Vision therapy can be particularly beneficial for individuals with intermittent exotropia or those with underlying binocular vision problems.
Eye patching: Patching the dominant eye (the eye that tends to turn outward less often) may be recommended to help strengthen the weaker eye and improve alignment.
Surgery: In cases where conservative treatments are not effective or if the exotropia is constant and severe, surgery may be recommended to correct the muscle imbalance and realign the eyes. Surgery involves tightening or loosening the eye muscles to improve eye alignment.
Botulinum toxin injection: In some cases, botulinum toxin (Botox) injections may be used to temporarily weaken the muscles that are pulling the eye outward. This can help align the eyes and improve symptoms, but the effects are not permanent and may require repeat injections.

The appropriate treatment for exotropia should be determined by an eye care professional based on a thorough evaluation of the individual case. It’s essential to follow up regularly with your eye care provider to monitor progress and adjust treatment as needed.

How is exotropia different from esotropia?

Exotropia and esotropia are both types of strabismus, which is a condition characterized by misalignment of the eyes. The main difference between exotropia and esotropia lies in the direction of the eye misalignment:

Exotropia: Exotropia is a type of strabismus where one or both eyes turn outward, away from the nose, when focusing on an object. It is often referred to as “wall-eyed” or “divergent” strabismus.
Esotropia: Esotropia, on the other hand, is a type of strabismus where one or both eyes turn inward, towards the nose, when focusing on an object. It is often referred to as “cross-eyed” or “convergent” strabismus.

While both exotropia and esotropia involve eye misalignment, they can have different causes, symptoms, and treatments. The underlying cause of exotropia or esotropia can vary and may include muscle imbalance, refractive errors, or neurological conditions. Treatment options for both conditions may include glasses, prisms, vision therapy, or surgery, depending on the specific needs of the individual.