Seeing things straight

In most cases, it can be easily seen, by merely looking at someone's eyes. Indeed, this is the way parents usually recognize that their children have strabismus (crossed eyes). Sometimes a kindergarten or primary school teacher will notice the condition first. Strabismus is a situation whereby the two eyes are not looking at the same point. The phenomenon is typically caused by an imbalance in the muscles of the eyeball, because of optical problems.

In addition to the easily identified form of this condition, there is also latent strabismus, which a doctor can diagnose as follows: He asks the patients to cover one eye and look straight ahead. If the uncovered eye moves and cannot focus on a given spot - that is a sign of the hidden form of strabismus.

Strabismus is most prevalent among children: Three percent of them suffer from it, as compared to 2 percent of adults. It is sometimes inherited, but there are no iron-clad situations here. Thus if a parent has suffered from it, the likelihood that his child will be cross-eyed is not necessarily high.

The medical literature indicates that even though a person with strabismus may have 20:20 vision in both eyes, he will not have three-dimensional, or depth, vision per se; the latter will be constructed in his brain on the basis of other clues received from the surroundings, such as size, light, shadow and so on. With respect to field of vision, too, the picture received in the brain of a person with strabismus is different from that of a person without the condition: In the latter situation, when a person looks straight ahead, his field of vision is 180 degrees, whereas a person with strabismus will have a limited field of 140 degrees.

Strabismus may develop among adults and is sometimes manifested in double vision. When an ophthalmologist discovers this, he must clarify its source. One possibility that it is a result of a neurological problem - perhaps of paralysis of one of the nerves that operate the eye muscles. In such a case, it is necessary to carry out an urgent neurological examination. If the problem is not neurological, it may be a case of strabismus from which the patient has suffered in the past. In this situation, an eye that has been treated and has succeeded in overcoming the strabismus for a time becomes weak again and the condition returns. In many cases, adults who suffer from cataract and retina problems may develop strabismus.

Two treatments

There are two ways of treating strabismus in both adults and children. The doctor may be able to fit them with glasses that solve the problem. In other, more severe cases, however, surgery is indicated and is carried out under full anesthesia; the procedure takes between half an hour and an hour. In most of the modern surgical procedures employed locally in recent years, the doctor weakens one or more eyeball muscles that are working too hard, and "pulls" the eye so that it looks toward the left or the right. Sometimes, however, the surgeon will strengthen muscles to help overcome the strabismus.

The decision of whether to weaken or strengthen muscles depends on the extent of the deviation of the eyeballs relative to each other.

Among adult patients, on occasion, some surgeons do not at first suture the area involved completely. Instead, they wait four or five hours and then carry out a thorough examination of the patient, with the aim of checking whether the eyeball has been completely straightened out. If not, they make final adjustments and put final sutures in place. The sutures melt over time and there is no need to have them removed. Immediately after surgery, the eye is bandaged and the patient must use drops for a number of weeks. These operations have a 70 percent success rate if the post-operative treatment is not carried out, and 90 percent if it is.

It is important to note that infections or loss of vision resulting from the above-mentioned procedures are very rare. Indeed, in general, this is a simple and easy operation, with tremendous physical and psychological benefits. A cross-eyed child is likely to grow up rejected by his classmates; a cross-eyed adult usually develops feelings of inferiority with respect to his appearance. In most cases, strabismus damages one's self-confidence and it can interfere with finding a job - or even a mate.

Can strabismus be prevented? I am asked this question by hundreds of mothers each month. My recommendation? Every infant should be checked during the period between six months and one year of age. In addition, examinations should be carried out at the ages of three and five by a pediatric specialist. It often happens that the doctor will notice that a child needs glasses, even though a general eye doctor has said that everything is fine. Every parent should realize that it is important to have their children's eyes examined, as early as possible. Over time, a strabismic eye that is not treated becomes a "lazy eye": Acuity of vision declines and cannot be fixed with the help of glasses or contact lenses.

Ocular medicine has progressed amazingly in the past decade and offers innovative solutions to problems of strabismus with excellent results. The right treatment, at an early age, will ensure beautiful and healthy eyes, and good vision.

Dr. Benjamin Shalev is an specialist in eyelid, tear duct and strabismus surgery at the Tel Aviv Medical Center.