Strabismus
STRABISMUS - is a permanent or periodical divergence of one eye from the common fixation point, which is caused by the disturbed mechanism of eye fixation at a single point.
Strabismus is more common in children. In about 60-80 % of cases strabismus develops at the end of second year of life. Th baby usually can see by one eye only, being unable to assess exactly the distance to an object, thus experiencing considerable discomfort. The cerebral centres do not receive a signal from a squint eye and accept the view from one eye only, thus, a squint eye finally becomes permanently partially sighted. The prognosis is worse in early occurring strabismus. Strabismus in up to 2 month old infants is considered as normal condition as eye movements in babies are not coordinated and babies are far-sighted. Binocular vision develops at the age of 5 months. Sometimes it can appear that an infant has strabismus. It depends upon the anatomical structure of the face: a larger or narrower bridge of the nose, the third eye-lid, ptosis of an eyelid of one eye or a deep set eye. In case of family strabismus history child vision should be checked even when there are no signs of visual pathology. This disorder can be inherited.
There are several strabismus types – when eyes are misaligned inward (cross eyed) or outward (lazy eye), vertical strabismus when one eye is oriented upward or downward, unilateral, affecting only one eye, alternating strabismus when both eyes may take turns being misaligned and paralytic strabismus when the eye movements toward the affected muscle are restricted.
People suffering from strabismus complain of rapid eye tiredness, dizziness, double vision. Children usually experience reduced vision or even blindness in one eye. In case of paralytic strabismus, a patient keeps his head turned to the side of affected muscle aiming to compensate double vision, a large pupil, immobile eye and eyelid ptosis can be reported.
Treatment of strabismus in children is initiated just after the diagnosis. Early diagnostics and provision of required care is associated with higher likelihood of recovery. Recovery period is long, usually lasting from infancy to adolescence. Usually strabismus is predetermined by high grade refractive errors (short-sightedness far-sightedness, astigmatism). In such case continuous use of glasses is required. The ophthalmologist prescribes appropriate glasses, a complex of curative exercises, irradiation by different devices. Such treatment aims to make ocular muscles working correctly and to improve vision. Children can use glasses since the age of 6 months. Sometimes an eye patch on the dominant eye is used to strengthen and correct the squint eye. Continuous treatment is required, as two weeks spent without glasses can come to nothing.
If the treatment with glasses is ineffective, surgical treatment is indicated – a surgery on the oculomotor muscles. They can be elongated or shortened. Sometimes several surgeries are required.
Regular eye check-ups in children are very important for strabismus prophylaxis. This is done at a maternity hospital, later the check-ups should be repeated at the age of one month, three months, half a year and one year and then twice per year. Better results can be expected if timely treatment was applied.