Strabismus

Causes

Muscles and nerves work together to move the eyes. Infants up to four months of age often have strabismus until their eyes straighten out. This is normal.

Strabismus can be present at birth or develop during the course of childhood. Some causes of it include:

• Visual problems with the eyes, like cataracts or farsightedness
• Problems with the muscles or nerves that support the eyes
• Trauma—this is more likely in adults
• Tumors—this is rare

The cause of strabismus is often unknown.

Risk Factors

Strabismus is most common in children, but it may happen in adults. Other things that may raise the chances of strabismus:

• Family members with strabismus
• Diabetes
• Thyroid disorders
• Retinopathy of prematurity
• Vision problems in one eye—the eye having problems will often turn in or out

Symptoms

Strabismus may cause:

• Crossed eyes
• Eyes that do not align properly
• Uncoordinated eye movements
• Double vision
• Problems with depth perception
• Eye strain, which may cause headaches or blurred vision
• Squinting
• Favoring a certain head position

Many aspects of strabismus are noticed by other people.

Diagnosis

The doctor will ask about symptoms and health history. A physical exam will be done. In general, eyes that do not align as they should can be seen. An eye specialist will test the eyesight and look for other problems. A neurological exam can help rule out other causes.

Treatment

Treatment may include:

Glasses

Glasses or contact lenses may be prescribed for the eye with weaker vision. The prescription lens helps the eye focus better and helps with poor vision. Better eyesight may help with improving strabismus.

For some health issues, special prism lenses can be placed in the glasses. The prism will help reduce double vision that may occur.

Patching

In children, an eye that is not properly aligned may not mature properly. If this is not corrected, permanent vision loss can happen. For some children, a patch is put over the unaffected eye. This forces the child to use the affected eye. This can help the visual development in that eye.

How long the patch is worn depends on how severe the strabismus is and the child's age.

Medicine

Eye drops or ointment may be put in the good eye to blur the vision for a short time. This also forces the affected eye to focus properly. These drops may be used instead of patching.

Injections of botulinum toxin may also be used to treat strabismus caused by muscle imbalances. The injections are used to partly freeze the muscle that is pulling the eye in the wrong direction.

Surgery

Surgery may be used to straighten the eyes if other treatments have not worked. The surgery may shorten certain eye muscles or move some of them into a new place. This may help the eye muscles keep the eyeball in its proper place.

Prevention

There are no current guidelines to prevent strabismus. A child whose eyes are not properly aligned should be taken to an eye doctor right away.