What Is Strabismus?
Strabismus is when eyes
don't line up or when one or both eyes wander. The eyes may turn:
- inward (called esotropia or "cross-eyed")
- outward (exotropia)
- up (hypertropia)
- down (hypotropia)
When eyes don't line up together, the straight or straighter eye becomes dominant.
The vision strength (acuity) of this eye stays normal because the eye and its connection
to the brain are working as they should. The misaligned or weaker eye, though, doesn't
focus as it should and its connection to the brain doesn't form correctly.
Sometimes, strabismus is very noticeable. Other times, it might only be noticed
when a child is tired or looking at something very closely.
Strabismus usually can be fixed when found and treated early. If it's not treated,
the brain eventually will ignore the visual images of the weaker eye. This change
— called amblyopia,
or "lazy eye" — can make vision blurry, cause double vision, and harm a child's
depth perception (seeing in 3D). These problems can become permanent if
they're not treated.
How Do Kids Get It?
Kids can be born with strabismus or develop it in childhood. Often, it's caused
by a problem with the muscles that move the eyes, and can run in families.
Most kids with strabismus are diagnosed when they're between 1 and 4 years old.
Rarely, a child might develop strabismus after age 6. If this happens, it's important
for the child to see a doctor right away to rule out other conditions.
What Are the Signs of Strabismus?
Most kids with strabismus don't complain of eye problems or notice changes in their
vision. Usually, it's a family member, teacher, or health care provider who notices
that the eyes are not straight.
Some kids may complain of double vision (seeing two objects when there's only one
in view) or have trouble seeing things in general. These problems also can affect reading skills and classroom learning. Younger kids who aren't talking yet may squint a lot and turn
or tilt their heads in an attempt to see more clearly.
If your child has any of these signs or symptoms, tell your health care provider. He or she can refer you to a pediatric ophthalmologist
for care, if needed.