A Condition Where the Eyes are not Aligned

What is strabismus?

Strabismus (often referred to as cross-eyes, lazy eye, wandering eye or squint) is a condition where both eyes are, either constantly or occasionally, not aligned with each other, despite looking at the same object.

There are several types of strabismus and they include: outward turning of the eye (exotropia), inward turning of the eye (esotropia), upward turning of the eye (hypertropia) or downward turning of the eye (hypotropia). The degree of the turning may also be mild or severe.

What causes strabismus?

There are a number of causes of strabismus and they include an imbalance in the degree of pulling from the muscles that control the position of the eyes or poor vision in one eye. It usually affects infants and children/adolescents, however, adults can experience the condition after trauma, a neurological disease, cardiovascular disease, or endocrinopathy (disease of the endocrine glands).

Infantile esotropia develops in infants before 6 months of age and often runs in families. Accommodative esotropia develops between the ages of 6 months and 7 years and the misalignment is the result of how the eyes move when focusing on nearby or distant objects.

Intermittent exotropia begins to occur after the age of 6 months and results when the child is focusing on distant objects or when they are tired or sick.

In paralytic strabismus, one or more of the muscles that move the eye becomes paralysed. This is usually due to nerve disruption caused by some viral illnesses, brain injuries or tumours that compress the nerves.

What are the signs and symptoms of strabismus?

Some signs of the more severe forms of strabismus are quite evident but in milder forms, parents may sometimes notice the condition because the child either squints or covers one eye. Individuals with strabismus may also experience double-vision, a decrease in vision or a permanent loss of vision if untreated.