Strabismus is the medical term used to define crossed eyes. People having such eyes will have one of their eyes looking in or out. They cannot focus in the same object like the other eye. One eye may turn up/down and this process is increased when the person gets stressed or with heightened emotion. The intensity of turning up/down of one of the eyes may be all the time or only during certain occasions.
Strabismus can be defined as some kind of misalignment of the eyes. Strabismus can be classified according to the direction of misalignment of eye. Some of the common kinds are exotropia (when eyes are turned in outward direction), esotropia (eyes are turned inward), hypertropia and hypotropia (both are types of vertical misalignment).
Strabismus Causes :
Often, strabismus or crossed eyes are inherited and the child is born with this defect. In some children, there is no specific cause for strabismus. It can be caused by nervous problem caused in the cranial nerves that are responsible for the movement of eyes. Any weakness in these cranial nerves can cause strabismus.
Crossed eye can be caused due to paralytic nerve and some kinds of such paralysis are oblique palsy and third nerve palsy. Strabismus can be caused due to poorly controlled neuromuscular movement. Often, strabismus can be repaired or corrected in childhood. In case necessary correction is not done, the same eye pattern will continue when the person grows into an adult. In some people, strabismus can cause double vision. If there is sudden problem in the eyes or misalignment (not from childhood) in otherwise healthy person, it can be due to serious nervous problem. In such case, you need to consult your doctor immediately.
Misalignment in the eyes can cause double vision or amblyopia. Normally when you see any object, the image of the object is perceived by the brain in the form of visual image. But in children with strabismus the brain receives two different images. Under such circumstances, the brain would ignore one image received from abnormal eye. Subsequently this can cause poor vision.
Who Are At Risk ?
Children who are born with congenital (by birth) strabismus are prone to develop misaligned eyes. If there is severe nervous problem or brain problem like cerebral palsy in the child, it can cause strabismus. Children with Down syndrome or tumor in the brain can develop strabismus later in life. In adults, people who have had a stroke have increased risk of developing strabismus. Grave’s disease can also increase the chance of getting strabismus. Severe trauma or accidental injury can affect the brain causing impaired eye movement. Sometimes it may cause nerve damage or it can affect the muscular movement of the eyes leading to strabismus.
No test is needed to detect strabismus. Any ophthalmologist can easily detect this condition.
Strabismus Treatment :
The ultimate goal of the treatment is to improve double vision and to correct the eye misalignment. Physical therapy and eye exercises are given to children to improve the muscular movement of the eyes. This type of therapy also helps in training the brain to receive the right image of the object. Eyeglasses, prism, optical devices and lenses are prescribed for correcting strabismus.
Surgery can also be done for repairing strabismus. The muscles that cause misalignment in the eyes are weakened during surgery. This can be performed under local anesthesia by numbing the eye that requires to be repaired. A small opening is made on the outer layer by the surgeon who would look out for the appropriate muscle and weaken it. In some people, the muscles are strengthened by cutting a small section at one end of the eye. The ends of the muscle are stitched back together by a suture.
After the surgery the patient may have problems in vision for few days until the brain adjusts to the new correction. However, your doctor will have to determine whether you are a right candidate for surgery. To improve the quality of life and to enhance the cosmetic appearance surgery can be done. For some people, even after surgery, double vision may continue. And additional surgery will be done for correcting the misalignment.
Effects Of Surgery :
Like any other surgery, eye surgery also carries some risk. It can cause headache, pain, pulling sensation in your eyes. Some people can feel the presence of foreign body in the eyes for few days after surgery. Your doctor may give painkillers to control the discomfort and pain. You need to abstain from doing any physical activities for many days and follow the instructions of your surgeon.