Strabismus exotropia is a common eye condition where one or both eyes turn outward, away from the nose. This deviation can be constant or intermittent. Exotropia affects both children and adults, and early recognition is important for effective management.
What is Exotropia?
Exotropia can manifest in several forms, each with distinct characteristics. Intermittent exotropia is the most frequently observed type, often appearing in childhood. In this form, the eyes may align normally at times but deviate outwards when a person is tired, daydreaming, or looking at distant objects.
Constant exotropia, on the other hand, involves a continuous outward turning of one or both eyes. Congenital or infantile exotropia is a persistent, large-angle outward deviation typically present within the first six months of life, sometimes associated with neurological or craniofacial disorders. Sensory exotropia can develop in an eye with poor vision or blindness, as the lack of clear input can cause the eye to drift outwards.
Exotropia differs from other forms of strabismus, such as esotropia, where one or both eyes turn inward towards the nose. Hypertropia involves an eye turning upward, while hypotropia involves an eye turning downward.
Identifying Exotropia
In children, exotropia might be more noticeable when they are tired, ill, or focusing on distant objects. Parents might also notice a child frequently closing one eye, especially in bright sunlight, or rubbing their eyes excessively.
Adults with exotropia may experience symptoms like eye strain, headaches, or blurred vision. Double vision, known as diplopia, can also occur, particularly if the condition develops later in life. Difficulties with reading or performing tasks requiring sustained near vision are also common reports. Seeking professional medical attention promptly, especially for children, is important to address the condition early.
Causes of Exotropia
Neurological conditions, such as cerebral palsy or certain brain disorders, can contribute to eye misalignment. A genetic component also exists, as strabismus, including exotropia, can run in families.
Refractive errors, such as uncorrected farsightedness or nearsightedness, can sometimes influence exotropia’s development. Poor vision in one eye can also lead to sensory exotropia, as the brain struggles to maintain alignment. In many instances, however, the exact cause may not be definitively identified.
Treatment Options for Exotropia
Managing exotropia involves various approaches, tailored to the individual’s age, the type and severity of the condition, and overall health. Non-surgical interventions are often the first line of treatment. Corrective eyeglasses or contact lenses can help address any underlying refractive errors that might contribute to the eye turn. Patching therapy, which involves covering the stronger eye for a period, can encourage the weaker, deviating eye to strengthen and improve its alignment.
Vision therapy exercises are another non-surgical option, focusing on improving eye teaming, focusing, and eye movement control. These exercises aim to enhance the coordination between the eyes and improve binocular vision. For some individuals, especially those with intermittent exotropia, these therapies can help reduce the frequency or magnitude of the outward turn.
When non-surgical methods are not sufficient, surgical intervention may be considered. Eye muscle surgery involves adjusting the length or position of the eye muscles to realign the eyes. This procedure aims to improve cosmetic appearance, restore proper eye alignment, and potentially enhance binocular vision. The decision to pursue surgery is made after careful consideration of the individual case and potential benefits.
Addressing Potential Consequences
If exotropia remains untreated, several long-term effects can arise. Amblyopia, commonly known as “lazy eye,” can develop, where the brain begins to ignore the visual input from the misaligned eye, leading to reduced vision that may become permanent if not addressed early. The ability to perceive depth accurately, known as binocular vision, can also be significantly impaired or lost, making tasks like catching a ball or navigating stairs more challenging.
Persistent double vision can also be a consequence, particularly when exotropia develops in adulthood, as the brain struggles to fuse the two disparate images it receives. Beyond visual implications, the cosmetic appearance of misaligned eyes can lead to psychosocial impacts, affecting self-esteem and social interactions. Therefore, timely diagnosis and appropriate treatment are important to mitigate these consequences and support visual health.