Strabismus is a failure of the two eyes to maintain appropriate alignment and collaborate as a team. If you have strabismus, one eye looks directly at the object you are seeing, while the other eye is crookeded inward (esotropia, “crossed eyes” or “cross-eyed”), external (exotropia or “wall-eyed”), upward (hypertropia) or down (hypotropia).
Strabismus can be consistent or periodic. The misalignment also may constantly affect the exact same eye (unilateral strabismus), or the two eyes may take turns being crookeded (rotating strabismus).
According to the American Association for Pediatric Ophthalmology and Strabismus, approximately 4 percent of the U.S. population has actually crossed eyes or some other type of strabismus.
Strabismus Symptoms And Signs
The main sign of strabismus is a visible misalignment of the eyes, with one eye kipping down, out, up, down or at an oblique angle.
When the misalignment of the eyes is big and obvious, the strabismus is called “large-angle,” describing the angle of discrepancy in between the line of sight of the straight eye and that of the misaligned eye. Less obvious eye turns are called small-angle strabismus.
Typically, continuous large-angle strabismus does not cause symptoms such as eye strain and headaches because there is essentially no attempt by the brain to correct the alignment of the eyes. Since of this, large-angle strabismus normally causes severe amblyopia in the turned eye if left neglected.
Less obvious cases of small-angle strabismus are most likely to cause disruptive visual symptoms, especially if the strabismus is periodic or rotating. In addition to headaches and eye strain, symptoms may consist of an inability to read comfortably, tiredness when reading and unsteady or “tense” vision. If small-angle strabismus is constant and unilateral, it can result in considerable amblyopia in the misaligned eye.
Both large-angle and small-angle strabismus can be psychologically damaging and impact the self-confidence of children and adults with the condition, as it hinders normal eye contact with others, often triggering humiliation and awkwardness.
Newborns typically have intermittent crossed eyes due to incomplete vision development, but this often vanishes as the baby grows and the visual system continues to grow. The majority of types of strabismus, nevertheless, do not vanish as a child grows.
Regular children’s eye exams are the best way to identify strabismus. Generally, the earlier strabismus is identified and treated following a child’s eye exam, the more effective the result. Without treatment, your child may establish double vision, amblyopia or visual symptoms that might interfere with reading and classroom learning.
What Causes Crossed Eyes (Strabismus)?
Each eye has six external muscles (called the extraocular muscles) that manage eye position and motion. For normal binocular vision, the position, neurological control and performance of these muscles for both eyes must be collaborated perfectly.
Strabismus occurs when there are neurological or anatomical problems that interfere with the control and function of the extraocular muscles. The problem might originate in the muscles themselves, or in the nerves or vision centers in the brain that control binocular vision.
Genes also might contribute: If you or your spouse has strabismus, your children have a higher risk of developing strabismus also.
Occasionally, when a farsighted child tries to focus to make up for uncorrected farsightedness, she or he will establish a type of strabismus called accommodative esotropia, where the eyes cross due to excessive focusing effort. This condition usually appears before 2 years of age however likewise can occur later in youth. Often, accommodative esotropia can be completely corrected with glasses or contact lenses.
For the most parts, the only effective treatment for a consistent eye turn is strabismus surgery. If your basic eye doctor discovers that your child has strabismus, he or she can refer you to an eye doctor who specializes in strabismus surgery.
For the most parts, the only efficient treatment for a consistent eye turn is strabismus surgery.
The success of strabismus surgery depends on numerous elements, including the instructions and magnitude of the eye turn. In many cases, more than one surgery may be needed. The strabismus cosmetic surgeon can give you more information about this during a pre-surgical assessment.
Strabismus surgery likewise can efficiently align the eyes of adults with enduring strabismus. In most cases of adult strabismus, nevertheless, a significant degree of amblyopia may stay after the affected eye is appropriately lined up. This is why early treatment of strabismus is so important.
The earlier strabismus is dealt with surgically, the most likely it is that the affected eye will develop normal visual acuity and the two eyes will work together effectively as a group.
Non-Surgical Strabismus Treatment
Sometimes of periodic and small-angle strabismus, it might be possible to enhance eye alignment non-surgically with vision therapy.
For example, merging insufficiency (CI) is a particular kind of periodic exotropia in which the eyes typically line up properly when seeing a far-off object, however cannot attain or preserve correct positioning when looking at close things, such as when reading, resulting in one eye wandering outward. Convergence insufficiency can hinder comfy reading, causing eye strain, blurred vision, double vision and headaches.
There likewise is some proof that suggests CI can cause attention problems and affect academic performance in children. A recent study carried out by Mayo Clinic scientists discovered that children with exotropia (including convergence deficiency) at an early age were substantially more likely to develop attention deficit hyperactivity disorder (ADHD), change disorder and discovering specials needs by early adulthood.
Certain types of strabismus also have been connected with an increased risk of myopia. Another Mayo Clinic research study released in 2010 followed 135 children with intermittent exotropia over a 20-year period and discovered that more than 90 percent of these children ended up being nearsighted by the time they reached their 20s.
On the intense side, it appears non-surgical vision therapy can be an effective treatment for merging deficiency. In a research study published in Archives of Ophthalmology, 73 percent of 221 children with symptomatic convergence insufficiency had an effective or enhanced result following a 12-week program of office-based vision therapy integrated with eye exercises performed at home.
Often, a strabismus surgeon might suggest a program of vision therapy for a period of time after strabismus surgery to treat amblyopia and minor binocular vision problems that might remain after surgery. In these cases, the term “orthoptics” (“ortho” = straight; “optics” = eyes) instead of “vision therapy” may be used to describe this treatment, which might be provided by an orthoptist working closely with the surgeon instead of by an optometrist.
Questions To Ask
When talking to your optometrist or strabismus surgeon prior to treatment, here are a couple of essential questions to ask:
- If surgery is advised, inquire whether one surgery will suffice or if extra procedures are most likely to be needed.
- Ask the eye surgeon about the success rates for the type of strabismus and the surgery she or he is recommending.
- Ask what requirements are used to determine if the treatment is a success. In other words, is “success” specified as reducing the eye turn so the eyes are much better lined up and look more natural in look, or is success specified as eyes that are perfectly lined up with normal visual skill, eye teaming and depth perception.
- For eye doctors or orthoptists, ask about the success rate, likely period and costs of vision therapy (or orthoptics).
- Ask what part of the costs of surgical or non-surgical treatments for strabismus are covered by health insurance or vision insurance coverage.
Remember, children do not “grow out of” strabismus. For best visual outcomes and to prevent developmental delays and other problems, seek treatment for strabismus as soon as possible.