What is pseudo-strabismus?
Strabismus is the medical term for eye misalignment, or squint. Pseudo-strabismus refers to a false appearance of strabismus. Most often, one or both eyes have the false appearance of turning inward (See figure below).
Why do some children's eyes look crossed?
The skin fold at the inner corner of the eyelids can be broad and is often associated with a broad flat nasal bridge (epicanthal folds, or epicanthus). These features contribute to a cross eyed appearance since there is less space (white area) between the iris and the inner corner of the eyelid. This is especially noticeable in pictures, or if the child is looking at you from an angle.
The child pictured appears to have an esotropia, or convergent squint. In fact, on examination, the eyes are straight.
Corneal light reflection test
This basic test can be performed on any child using a penlight. As a child focuses on a penlight, the position of the light reflection from the front surface (cornea) of the eye is observed. The test is accurate only if the child looks directly at the light and not to the side. Normally the corneal light reflex is centered on both pupils. The test is abnormal if the corneal light reflex is "off-center”, or asymmetrical (see below).
Why is it important to differentiate pseudo-strabismus from true strabismus?
True strabismus in a child can lead to permanent vision loss and is best treated early. If a child is suspected of having strabismus, a complete eye examination is recommended.
It is often difficult to differentiate between true strabismus and pseudo-strabismus.
What is the treatment of pseudo-strabismus?
Pseudo-strabismus is common, especially in young babies, and does not require treatment. As facial features mature, the widened nasal bridge tends to narrow, and the appearance tends to improve with time.
Asian children may retain a broad nasal bridge into adulthood and this is perfectly normal.