When a person’s eyes aren’t aligned, they don’t work together as a team. This is known as strabismus, which you’ve heard colloquially deemed “crossed eyes.” The condition can be constant or intermittent. Because the brain is receiving two different signals, it begins to ignore one of the eyes, which typically leads to amblyopia, lazy eye.
Dr. Thom treats strabismus in our patients from Fargo and the surrounding areas.
What is strabismus?
Strabismus is a condition in which both eyes do not look at the same place at the same time. Also known as having crossed eyes, this moniker isn’t completely accurate, as strabismus can have the effect of the eyes looking over toward the center, but they can also look outward, or upward or downward.
Our eyes have six muscles that control movement. When the eyes are normal, all six muscles work together and point both eyes in the same direction or object. Patients with strabismus have problems with the control of eye movement and cannot keep normal ocular alignment.
Strabismus usually develops in infants and young children, typically by the age of 3. Older children and adults can develop the condition, but this is far less common.
Strabismus is classified by the direction the eye turns:
- Esotropia — the eye turns inward
- Exotropia— the eye turns outward
- Hypertropia — the eye turns upward
- Hypotropia — the eye turns downward
What are the symptoms of strabismus?
The primary sign of strabismus is a visible misalignment of the eyes, with one eye turning in, out, up, down, or at an oblique angle. Large-angle strabismus is the term when the misalignment is large and obvious. Small-angle strabismus is less noticeable and maybe alternating or intermittent.
Large-angle strabismus typically doesn’t cause symptoms such as eye strain and headaches because there is virtually no attempt by the brain to straighten the eyes. Because of this, large-angle strabismus usually causes severe amblyopia, where the brain simply ignores the signals coming from the misaligned eye.
Small-angle strabismus is much more likely to cause disruptive visual symptoms, especially if the strabismus is alternating. Headaches, eye strain, inability to read comfortably, fatigue when reading and unstable or “jittery” vision are common symptoms.
What causes strabismus?
Most strabismus results from an abnormality with the patient’s neuromuscular control of his or her eye movement. It’s less common for it to be an anatomical problem with the six extraocular muscles. Strabismus has a genetic association, with about one-third of children with strabismus having a family member with a similar problem.
Various other conditions can be associated with strabismus:
- Uncorrected refractive errors
- Poor vision in one eye
- Cerebral palsy
- Down syndrome
- Brain tumors
- Strokes (the leading cause of adult strabismus)
- Head injuries
- Neurological problems
- Graves’ disease
In what is known as accommodative esotropia, a farsighted child tries to focus to compensate for uncorrected farsightedness and the eyes cross due to excessive focusing effort. This condition usually occurs before the child is 2 years old. It can be fully corrected with eyeglasses or contact lenses.
Can adults develop strabismus?
Whereas around 4 percent of U.S. children have strabismus, it’s not as common in adults. Many adults have had strabismus since childhood, but it was small-angle strabismus, and it simply becomes more noticeable. If strabismus develops suddenly in an adult, it’s important to look for causes such as strokes, tumors, and thyroid eye disease.
What is the difference between strabismus and a lazy eye?
Strabismus is a misalignment of the eyes, where both eyes are not focusing on the same area. Lazy eye, clinically known as amblyopia, is often a result of strabismus. In amblyopia, one eye doesn’t develop normally. This is typically due to alignment issues. The brain cannot handle two different visual signals coming in, as the eyes are aimed at two different objects/areas at the same time. Its way of coping is to ignore the signals from one of the eyes. Over time, this causes the ignored eye to deteriorate, even leading to blindness in the ignored eye.
What happens if strabismus is left untreated?
People often think strabismus is a passing condition that will correct itself. This can only really be true with newborns, who have intermittent crossed eyes due to incomplete vision development. This frequently disappears as the baby’s vision system matures.
Most types of strabismus, however, will not go away or improve. The condition will actually worsen if left untreated. Lazy eye is a common result, as the brain ignores the signals from one of the two eyes and the eye development ceases. Beyond that, blurry vision will affect performance in school or at work. The person will have continual eye strain, fatigue, headaches, double vision, and even poor three-dimensional vision. Also, if the condition is obvious in the person’s facial appearance, it will lead to low self-esteem.
If your child is over 4 months old, and his or her eyes do not appear to be straight all the time, this merits an appointment with Dr. Thom to check the child’s visual alignment.
What are some strabismus treatment options?
Dr. Thom may use one of several treatment options to improve the patient’s eye alignment and coordination. These include:
- Eyeglasses or contact lenses — This corrects the refractive errors, typically farsightedness, that is causing the straining of the eye muscles.
- Prism lenses — These special lenses are thicker on one side than the other. The prisms alter the light entering the eye and reduce how much turning the eye must do to view objects. Sometimes these lenses can eliminate the eye turning.
- Vision therapy — Vision therapy trains the eyes and brain to work together more effectively. These visual activities and exercises can help problems with eye movement, eye focusing, and eye teaming, and they can reinforce the eye-brain connection.
- Eye muscle surgery — Surgery can physically correct the length or position of the muscles controlling the eyes.
What surgery is used to correct strabismus?
In most cases, the only effective treatment for a constant eye turn is strabismus surgery. Dr. Thom performs these procedures. He changes the length or position of the muscles around the eyes to straighten their orientation. Surgery is the most likely treatment that will allow the patient to develop normal visual acuity and have their two eyes function together properly as a team.
Is strabismus surgery painful?
Recovery after strabismus surgery with Dr. Thom is not overly painful for children or adults. There will be mild pain and swelling around the eye, but this will resolve in a few days.
Schedule a Consultation
If you’re interested in learning more about strabismus please contact us for a consultation at (701) 235-5200 or fill out our contact us form. We will discuss your needs and concerns, and determine your best course of action.