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Alaska Blind Child Discovery

A cooperative, charitable research project to vision screen every preschool Alaskan

Fixation & Cover Test


Infants often have occasional misalignment of their eyes, but should have straight eyes with ability to fix and follow interesting small objects. Any infant who cannot align their eyes has some form of "STRABISMUS." Constant strabismus often results in pediatric vision loss due to "Strabismic Amblyopia." Crossed eyes (esotropia) is more likely to cause amblyopia than wall-eye (intermittent exotropia).

The AAP recommends that all infants be carefully screened for strabismus using a cover test and tests of fixation.

An interesting object, ie detailed small toy, should be presented and passed side-to-side observing whether the eyes together, and independently (covering one with your hand), can accurately and smoothly follow. Then switch the covering hand from right to left observing for a "jump" to regain fixation.

The Hirschberg Corneal Light Reflex is also helpful in detecting strabismus.

A translucent occluder is passed from right eye to left eye observing for a "jump" in refixation indicating strabismus:
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