Misaligned or crossed eyes is a condition medically known as strabismus, and it’s more common than you might realize. Strabismus afflicts about 4% of the population, according to the American Association for Pediatric Ophthalmology and Strabismus.
The good news is that strabismus can have a high treatment success rate, especially when diagnosed early. Strabismus can be detected during an exam by a pediatric eye specialist – yet another good reason to stay up on the recommended pediatric eye exam schedule.
Despite what your parents might have said to prevent you from misbehaving as a kid, your eyes will not stay crossed simply from making a funny face. Strabismus arises when there is an anatomical or neurological dysfunction that negatively impacts your extraocular muscles, the ones that control your eye movement.
Your 6 extraocular muscles work with adjacent nerves and your brain to coordinate movement in both eyes. The brain sends signals via the nerves to the muscles to direct their motion. Normally, the muscles direct the eyes to focus on the same point at the same time.
When this delicate interplay between extraocular muscles and coordinating neurological functions is off, the eyes may not maintain proper alignment or work together as they should. Strabismus essentially throws off binocular vision, or the vision that uses both eyes’ overlapping fields of view.
Strabismus may cause the eye to turn:
- Outward (exotropia)
- Inward (esotropia)
- Downward (hypotropia)
- Upward (hypertropia)
Strabismus can be further classified by:
- Its frequency – whether it is constant or intermittent.
- The number of eyes affected – if it is one eye (unilateral) or both (alternating).
- The degree of misalignment – significant and obvious misalignment is called large-angle, while less noticeable is called small-angle.
Have had or currently have strabismus
Is My Child at Risk?
Parents should be aware that strabismus often occurs in otherwise healthy children. The condition typically develops in babies and young kids – often by age 3 – although older children and even adults can have it.
There may be a genetic component to strabismus, making the child of a parent with the condition more likely to have it. Also, certain disorders that affect brain function like hydrocephalus or cerebral palsy can make developing strabismus a greater possibility.
Occasionally, a child with uncorrected farsightedness will develop what is called accommodative esotropia. This occurs when the child uses excessive effort to focus their eyes as a way to compensate for poor sight. Usually the condition presents before age 2, but onset later in childhood is possible. Unlike other types of strabismus, accommodative esotropia may be entirely corrected with prescription lenses.
Signs of Strabismus
The primary sign of strabismus is noticeable eye misalignment, whereby the eyes are not working as a team and one eye turns out, in, down or up.
During early vision development, newborns may have intermittent eye misalignment. Infants should outgrow this relatively quickly as their eyes and brains mature. By about 4 months, infants’ eyes should be working in tandem, and apparent eye crossing or misalignment should no longer be present.
A couple of essential facts about strabismus:
- Beyond the first few months of life, eye misalignment and crossing is not normal.
- Contrary to popular misconception, a child will not outgrow it on their own.
An ophthalmologist or optometrist should examine a child who displays signs of strabismus right away. A pediatric eye exam performed by an eye specialist is the surest way to receive an accurate diagnosis and a treatment plan with a successful outcome.
Why Strabismus Should Be Treated Right Away
Delayed treatment for strabismus can lead to the condition worsening, or to related vision problem, such as:
- Double vision – the simultaneous perception of two images, usually overlapping, of a single scene or object. This can happen in people with misaligned eyes since the brain is receiving different images from each eye to process.
- Amblyopia – better known as lazy eye, this is when vision in one eye is weaker than the other eye. In strabismus patients, this can happen over time as the brain ignores visual input from the misaligned eye. Patients with large-angle strabismus are at greater risk of developing lazy eye.
Other symptoms, more common in small-angle and alternating strabismus patients, are headaches, eye strain, unstable vision and difficulty reading (due to eye fatigue).
Besides inducing physical side-effects and vision impairments, strabismus can be damaging to a child’s self esteem. Past a certain age, a child with strabismus will be aware of their abnormal eye alignment. Strabismus can make normal eye contact with other people difficult, creating additional obstacles to positive social interaction.
Effectively Treating Strabismus
Strabismus treatment seeks to improve eye alignment and binocular vision. Some patients, especially with small-angle or alternating strabismus, may benefit from eyeglasses. The earlier strabismus is detected and treated, the greater the chances of fully correcting strabismus with non-surgical options.
In many cases, particularly for large-angle or constant strabismus patients, the sole effective form of treatment is surgery. The surgery involves loosening or tightening the extraocular eye muscles to alter the alignment of the eyes.
Strabismus surgery can effectively align the eyes in children. It should be noted that significant weakness in one eye may remain, despite lazy eye treatment and strabismus surgery, in patients who have had long-standing strabismus. This is yet another reason why regular eye exams with a pediatric ophthalmologist or optometrist are so important.
3 Questions To Ask Your Eye Doctor Before Surgery
Surgery – especially involving our children – can be a nerve-wracking experience. Below are a few questions to ask your surgeon, so that you feel better prepared before your child goes in for the procedure.
- Ask your eye surgeon about their success rates in treating your child’s type of strabismus.
- Find out what criteria are used to label a treatment a success. “Success” for one practitioner may be reducing the eye turn for better alignment. Another surgeon may only call a “success” eyes that have achieved perfect alignment and normal depth perception and vision.
- Ask if one surgery will be enough, or if additional operations are likely to be needed.
A reputable eye doctor can answer these and other concerns you may have about treating your child’s strabismus. Of course, we all want what is best for our kids, and finding the right doctor to diagnose and treat strabismus is another way of giving our kids the best shot for a happy and healthy future.