Strabismus is a condition of the eye wherein the visual axes of the left, and right eye both are not aligned properly, unlike to the normal condition where both the eyes are in perfect alignment. A person suffering from this condition have both of his or her eye aligned in a different direction; both eyes appear to be looking in the opposite direction. Simply put, strabismus is an eye condition in which both the eyes are unable to focus on an object properly owing to reasons such as a defect in the ocular muscles or the brain's inability to coordinate their movement respectively.

As per the eye specialists, strabismus of myriad types, however, for the layman, it can be classified into four broad types including, Exotropia, Esotropia, Hypertropia and Hypotropia.

Exotropia, also known as divergent strabismus, is a condition where the visual axes of the eyes are focused in diverged manner. Esotropia, commonly called as convergent strabismus, is a condition in which the visual axes of the eyes are focused inward. Hypertropia and Hypotropia are the forms of Vertical strabismus,  where the eyes move abnormally in upward and downward direction.  The most common forms of strabismus are Exotropia and Esotropia, the Divergent and Convergent Strabismus respectively.

The condition is highly dangerous due to following two reasons:

1. It creates difficulty in vision

2. It impairs the victim to have a proper depth perception

3. It compels the victim to rely on the dominant eye for visual sensation

Also, since due to this eye condition, the brain of the victim adapts to focus on one eye, the use of the other eye is considerably reduced. This, in turn, can cause blindness in that eye. This cosmetic defect offers adverse psychological effects on the victim.

Causes:

There can be two types of causes which can result in strabismus, namely

  • Paralytic Strabismus
  • Non-Paralytic Strabismus

A defect in the cranial nerves that connect to the eye causes paralytic strabismus. This condition causes a lesion in the cranial nerve. Cranial nerve III, (oculomotor), IV (trochlear) and V (abducens) are most prone to the lesion formation.

in the case of non-paralytic strabismus, the problem is not related to the nerves. Instead, it generates due to a defect in the refraction of the eyes. Hence, no lesion is formed in the case of non-paralytic strabismus

Symptoms:

If both the eyes in an individual appear coherent and uncoordinated, he or she suffers from strabismus.  While one eye in such victims functions normally, the other eye is focused in a different direction.

Diagnosis:

After witnessing the symptoms, this eye condition is diagnosed by an optometrist, an optician or an ophthalmologist or a medical doctor specializing in eye and its diseases. The doctor suggests the victim undergo a cover test. Strabismus is diagnosed only when the vision of the defective eye is absolutely normal when the dominant or normal eye is covered.

Treatment:

The objective of the strabismus is to make sure that the patient restores his or her normal binocular vision.

With that being said since the condition involves risks such as blindness or amblyopia, it is carried out by making the patient wear an eye patch both on the dominant and normal eye so that the eye that is weaker gets to catch up over the time. This technique is one of the oldest management methods in order to treat strabismus.

The type of treatment chosen can depend on the particular case and requirement. This eye condition can be corrected with the help of glasses and prism lenses. But, extreme strabismus would require surgery.