If you have strabismus, one eye looks directly at the object you are viewing, while the other eye is misaligned inward (esotropia) outward (exotropia) upward (hypertropia) or downward (hypotropia).
Strabismus can be constant or intermittent. The misalignment also might always affect the same eye (unilateral strabismus), or the two eyes may take turns being misaligned (alternating 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.
When the misalignment of the eyes is large and obvious, the strabismus is called “large-angle,” referring to the angle of deviation between the line of sight of the straight eye and that of the misaligned eye. Less obvious eye turns are called small-angle strabismus.
Corneal light reflex test is a screening test for strabismus that evaluates eye alignment based on the location of reflections of light shined at the eyes.
Typically, constant large-angle strabismus does not cause symptoms such as eye strain and headaches because there is no attempt by the brain to straighten the eyes.
Less noticeable cases of small-angle strabismus are more likely to cause disruptive visual symptoms, especially if it is intermittent or alternating. In addition to headaches and eye strain, symptoms may include an inability to read comfortably, fatigue when reading and unstable vision.
Newborns often have intermittent crossed eyes due to incomplete vision development, but this frequently disappears as the infant grows and the visual system continues to mature. Most types of strabismus, however, do not disappear as a child grows.
Routine children’s eye exams are the best way to detect strabismus. Generally, the earlier strabismus is detected and treated following a child’s eye exam, the more successful the outcome. Without treatment, your child may develop double vision, amblyopia or visual symptoms that could interfere with reading and classroom learning.