Strabismus - squint

Squint, or strabismus as a technical term, is a visual disorder when cooperation between both eyes is disrupted. In such a case each eye points in a different direction. In strabismus if one eye looks directly forward then the other one points inward, outward, upward or downward. The angle of eye deflection from a normal position is called a deviation. Deviation can be permanently visible or it sometimes appears and then disappears.

Strabismus is a relatively common disorder which affects approximately one child out of thirty. Boys and girls are equally affected. Strabismus is often inherited but it is true that many squinters do not have any ancestors or relatives affected by strabismus.

Causes of strabismus

The exact cause of squint is not yet entirely clarified. However, refractive disorders (for example high dioptric difference between both eyes), disorders of the ocular muscles or their innervations are considered to be the main causes of squint. Eye movement is exercised by six ocular muscles. Two of these muscles influence eye movement to sides and four muscles move the eye upward and downward. The accurate focus of both eyes on one observed object depends on perfect synchronization of all twelve ocular muscles. Muscle activity is controlled by complex brain centers. Squint is more common in children who suffer from diseases which affect the brain such as: poliomyelitis, hydrocephalus, brain tumors and Down syndrome.

Squint can be caused by cataract, eye injury or other eye diseases which influence the vision. On the other hand it is true that in a large percentage of children it is not possible to find any associated disease which could be connected with the formation of strabismus.

Symptoms of strabismus

The main symptom of squint is a deviation of the eye to certain direction while the other eye looks directly. Other symptoms can include narrowing one eye or moving head to the side with the aim to focus on observed object.

Possibilities of strabismus treatment

In general it is true that the earlier the strabismus treatment begins the higher is the chance of correcting it. In the case when strabismus is diagnosed after sixth year of life there is a very low probability that conservative treatment will be effective.

It is necessary to undergo a complex eye examination immediately after any type of squint emerges. The cause of strabismus can be determined based on the results of the examination and the treatment can be prescribed.

If a dioptric disorder is the cause then the solution is to correct it by eyeglasses. It is important to cover healthy eye with an eye patch to prevent the formation of amblyopia. This will force squinting eye to try to see properly. One can also use various pleoptic and orthoptic exercises.

When conservative treatment is not sufficient then a doctor recommends surgical treatment. It is usually performed on both eyes. It consists of cutting the conjunctiva and through created opening a surgeon adjusts the length or movement of the ocular muscles. The aim of surgical strabismus treatment is to achieve balanced position of the eyes.

The final result of surgery is influenced by accurate execution of orthoptic exercises and wearing of prescribed eyeglasses.

It can happen that first surgery is not sufficient and after certain time it is necessary to repeat it because squint returned again and sometimes in opposite direction.

In cases of elder patients, surgical procedure is often only an esthetic affair when the aim is to achieve balanced position of the eyes because as a result of untreated strabismus in childhood large percentage of patients suffers from amblyopia on one eye which cannot be treated and the visual sharpness remains limited.