Anisometropia is a condition in which
the power of refraction (i.e. change in direction of light
rays as they pass from one optical medium to another, of a different refractive
index) in the right-eye differs significantly from the power of refraction
in the left-eye.
Possible effect on young children:
Anisometropia is a particular concern in young children
because it can lead to amblyopia
(common name: "Lazy Eye"), in which one eye significantly under-performs
compared with the other eye. This can occur because when the degree of
anisometropia reaches or extends beyond a certain level,
the brain cannot reconcile the two different images coming from the two
eyes and so develops a preference for the image coming from one eye and
suppresses the image from the other eye, effectively starting to cease
use of the eye not favoured by the brain.
Other possible effects of anisometropia:
Irrespective of the age of the patient, if untreated anisometropia
can lead to diplopia
(commonly known as "double-vision") or eyestrain.
More about Ophthalmology: This section includes short definitions
of many diseases, disorders, and conditions of the eyes and visual system.
For definitions of other terms in this category, choose from the list
to the left (but note that this is not a complete/exhaustive list).
Other related pages include the diagram
of the eye, and definitions
of parts of the eye, a description
of the human retina, and definitions
of parts of the retina, and the section of short definitions
of clinical and surgical procedures re. eyes and human visual system.
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