Esotropia or crossed eyes

What causes esotropia?

Our eye movements are controlled by extraocular muscles. These muscles keep our eyes aligned when we are looking at an object. If there is a problem with these muscles it may result in different types of eye misalignments such as esotropia.
A patient's family history may also contribute to this condition. Approximately 30% of children with strabismus have a family member with the same condition.
Esotropia can also be caused by:

• Refractive errors such as farsightedness
• Poor vision in one eye
• Head injuries
• Neurological issues such as down syndrome, cerebral palsy, hydrocephalus, brain tumors
• Certain systemic diseases, like hyperthyroidism or diabetes

How is esotropia treated?

Esotropia must be detected and treated early in order to be effectively treated. During the early stages of development, the child's brain is adaptive and has a high chance of responding well to treatment. The good news is that there are effective treatments for esotropia for patients of all ages. Treatment of esotropia is determined on a case by case basis, where the functional optometrist will assess the underlying causes of the esotropia and the ideal treatment for that patient.

Treatment for esotropia involves treating the underlying cause, which may include:

• Double vision
• Weak extraocular muscles (responsible for eye movements)
• Farsightedness (hyperopia)
• Amblyopia (lazy eye)
• Binocular vision dysfunction

Vision therapy: Vision therapy has been shown to be an effective, permanent, and non-invasive way to treat esotropia. The goal of vision therapy is to train the brain to use both eyes in tandem to achieve great vision. Vision therapy for esotropia is often done in combination with special prism lenses. The therapy is done in office under the guidance of the functional optometrist and a vision therapist. The in office sessions follow a series of repeated exercises,tailored to the patient's visual deficits and progress. You can schedule an eye exam for vision therapy with our developmental optometrist by calling (423) 710 3965.

Patching is another treatment option especially in patients with acquired esotropia caused by amblyopia. This option forces the brain to utilize the eye that has been ignored. For best results patching should be done in combination with vision therapy in order to promote binocular vision once the amblyopic eye is being used.

Surgery may be performed on your extraocular muscles to fix the misalignment of your eyes. It is performed by an ophthalmologist which may be recommended by our optometrist if necessary. Ideally surgery is done in combination with vision therapy, which allows for the combination of fixing the muscle alignment while reintegrating binocular vision for the patient through therapy.

With eyeglasses, accommodative esotropia can be treated by reducing focusing effort and convergence of the eyes.

Eyeglasses with prisms may also be prescribed to correct the misalignment of the eyes, effectively correcting esotropia.

Types of esotropia

Intermittent esotropia

This type of esotropia does not cause eye deviation constantly. If a person has this type of esotropia, their eyes may deviate inward after doing near work for a long time.

Infantile esotropia

Infantile esotropia usually manifests within the first six to twelve months of life. Most children develop controlled eye movements before the age of 6 months, but they don't have them during the first few months of life. Esotropia in infants is evident by a large angle deviation. It is also associated with latent nystagmus.

Accommodative esotropia

Typically, this type of esotropia develops between 1 and 4 years of age. Initially, it is intermittent, but over time it becomes more frequent. It usually occurs in children who are more farsighted than usual. Their eyes have to work harder to see clearly when viewing an object that is up close. Due to this excess effort, the eyes become over-converged or crossed.

Acquired esotropia

Unlike esotropia that develops earlier in life, acquired esotropia develops later in life. It could be due to untreated hyperopia (inability to close up objects clearly), double vision, lazy eye (amblyopia) or diabetes.

Sensory esotropia

This type of esotropia occurs in children less than 4 years old. A child with impaired vision in one eye is most likely to suffer from this condition. To get clear vision, our brain must fuse images from both eyes. When one eye does not have good vision, it drifts inwards causing esotropia.