Strabismus
Strabismus, commonly referred to as crossed eyes, is a condition characterized by improper alignment of the eyes, where one or both eyes may deviate inward, outward, upward, or downward. Affecting approximately 5 percent of the population, strabismus can arise due to issues with the eye muscles or nerve supply, and it may also be linked to poor vision in one or both eyes. Symptoms often include the noticeable appearance of crossed eyes, double vision, and difficulties with depth perception, which can lead to amblyopia or dimness of vision if left untreated.
Diagnosis can involve the "corneal light reflex test," which evaluates the symmetry of light reflections off the pupils. Various treatment options exist, ranging from surgical intervention to the use of glasses, bifocals, eye patches, or eye drops. The primary goal of treatment is to prevent amblyopia and to realign the eyes to restore proper depth perception. It is crucial for individuals with strabismus to consult an ophthalmologist, who can provide tailored care and management to improve vision outcomes.
Strabismus
ALSO KNOWN AS: Crossed eyes
ANATOMY OR SYSTEM AFFECTED: Eyes, muscles
DEFINITION: The improper alignment or crossing of the eyes
CAUSES: Improper alignment of eyes
SYMPTOMS: Appearance of having crossed eyes, double vision, loss of vision or depth perception
DURATION: Temporary to long-term
TREATMENTS: Surgery, glasses and bifocals, patching, eye drops
Causes and Symptoms
Strabismus affects approximately 5 percent of the population. It may be caused by a problem with the nerve supply to the muscles that move the eye or by poor vision or of vision in one or both eyes.
The most common type of strabismus is an esotropia (inward deviation) of the eye, which accounts for 75 percent of the cases of crossed eyes. There is also exotropia (outward deviation), hypertropia (upward deviation), and hypotropia (downward deviation) of the eye. When a child with strabismus has a penlight shone in the eye, the light reflected back does not fall on the in the same place. This is referred to as the "corneal light reflex test." When the eyes are aligned, the corneal light reflex will be placed symmetrically on the pupil. It is important to identify strabismus and to have it evaluated to prevent amblyopia (dimness of vision) or in the eye that is deviated. It is also important because, without input from both eyes, it is difficult to perceive depth.
A condition called "pseudostrabismus" gives the appearance of having crossed eyes. It occurs because there is a flat bridge of the nose or extra skin near the nose. In this situation, the corneal light reflex will be symmetrical in the pupil.
Treatment and Therapy
Treatment of strabismus is aimed at avoiding amblyopia and realigning the eyes to restore depth perception. This realignment frequently requires eye muscle surgery. Some cases can be treated with glasses and bifocals. Patients with strabismus and amblyopia are typically prescribed glasses and may be given an eye patch to be worn over the stronger eye in order to strengthen the affected eye. Eye drops are may be substituted for patching. An ophthalmologist should be consulted for the treatment of strabismus.
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