Diplopia

What is diplopia?

Diplopia means double vision.

There are two types of diplopia. The first can occur when both eyes are open, and disappear when you cover either eye. This is called binocular diplopia, which is related to a loss of parallel axes of the two eyes, with deviation of one eye (strabismus).

This deviation may be due, among other things …

• to a neurological problem (for example, partial paralysis of one of the three nerves responsible for eye movements),
• to a muscle problem (for example, inflammation of one of the six muscles allowing eye movements),
• to a problem in the orbit, the bone structure that contains the eye and the muscles that make it move (for example, inflammation or a tumour).

In cases of strabismus in children, very quickly the brain no longer takes into account the perception of the deflected image, which eliminates double vision. The risk is then that the brain neglects visual learning with the deviated eye, causing poor vision, that is to say, amblyopia.

Double vision can also be present not only with both eyes open, rather it may persist when you cover one eye. This is monocular diplopia, which is due to an alteration in the passage of light rays through the transparent media of the eye, such as a refractive disorder (astigmatism) or opacity of the cornea or lens (cataract).

What are signs of diplopia in children?

Infants describe double vision, either for all distances or only in near or far vision. Double vision may or may not disappear by covering one eye. In cases of binocular diplopia, the deviation of the eyes (strabismus) may or may not be visible. In cases of monocular diplopia, generally speaking, no abnormality is visible to the naked eye. The child does not have strabismus, for example.

How can diplopia be screened for?

Diplopia must be treated without delay, in order to determine the cause and avoid the onset of amblyopia in children.

The diagnosis requires an ophthalmological examination, often combined with an orthoptic examination in cases of binocular diplopia. Depending on the case, additional investigations, such as laboratory tests or imaging, may be necessary.

How can diplopia in children be treated?

Monocular diplopia can often be resolved by the prescription of glasses.

A binocular diplopia can be relieved by prisms, which make it possible to align the shifted images, by the wearing of an occlusion (patch) on the deviated eye if a correction by prism is impossible, or by a surgical realignment of the eyes.

Find out more about children's visual disorders

Do you want to learn more about a particular visual condition? Discover our pages on myopia, dry eye, hyperopia, nystagmus, congenital glaucoma, and eye allergies. We explain these visual disorders and tell you how to treat them to preserve your children’s visual acuity.