How to identify strabismus in children?

We all have small defects in the face, eyes, and other parts of the body, even a very slight degree of strabismus. However, this is barely detectable, and overt or really obvious strabismus is only seen in 5% of the population.

But, what is it? Why does this happen? And how can we detect strabismus in our child?

What is strabismus?

Simply put, strabismus is an eye misalignment. That is when drawing a straight line we can see a marked difference between both eyes.

In many cases, strabismus is associated with problems with brain development. For example, in down syndrome, the risk increases 20 to 30 times. In other cases, it has nothing to do with cognitive ability.

When there is strabismus, each eye is directed to different parts of the visual field. This can cause confusion when two objects are perceived simultaneously in the center of the visual field. It can also cause diplopia or double vision. However, in those who have strabismus, vision is suppressed in one of the eyes to correct vision and allow the individual to see clearly.

How to evaluate a child with strabismus?

If you suspect that your child suffers from strabismus, there are several ways to assess the problem:

  • Visual acuity tests: using the E test, also known as the Snellen test. In this test, you may find yourself unable to pin up either of your eyes. You might even see rejections movements at the moment that covers the good eye.
  • Eye movement evaluation: in this exam, the child’s eyes are evaluated in 9 positions. These are the central position of the eyes, towards the four cardinal points, and then up and to the right, down and to the right, up and to the left and down and to the left. In each case, how the eye muscle functions on each side are evaluated.
  • Cover test: it is one of the most common and easy tests to perform. Only one of the eyes is covered and it is evaluated if the uncovered eye moves reflexively. Then, it is confirmed if there is a reflex movement of the eye when uncovering.

These tests might seem complex, and there are even many more that can be done. It may be especially difficult to detect strabismus in a child or a very young kid. For this reason, we recommend that you go to an ophthalmologist for a complete evaluation and thus detect and treat strabismus in the most appropriate way.

Thanks to Dr. Loania Restivo Milanes, for reviewing and verifying this article. She completed the Specialty in Ophthalmology at the Conde de Valenciana Foundation Ophthalmology Institute in Mexico City in 2001 and the Bachelor’s Degree as Surgeon in Havana, Cuba in 1995. He has 25 years of medical experience and has specialized in Cataract Surgery, Glaucoma , Myopia and Retina.


  1. About Kids Health
  2. American Academy of Ophthalmology