Diplopia is also known as Double
Vision (or Double-Vision).
Diplopia may be described as the simultaneous awareness
of two images of the same object. The two images may be
- displaced horizontally, vertically, or diagonally (i.e. both vertically
and horizontally) in relation to each other, and/or
- may over-lap each other (to varying extents), and/or
- may be diffuse / blurred / out-of-focus.
Diplopia may occur because the two eyes are unable to
move normally such that both are looking at, and focussing correctly,
onto a particular object. This may be due to problems with
- nerves controlling movement of one or both eyes,
- muscular problems moving one or both eyes, or
- some mechanical restriction resisting movement of one or both eyeballs
in their respective sockets.
Examples of conditions in which the eyes are misaligned such that diplopia
may result include squints such as esotropia
In some cases diplopia may occur as a temporary
effect or symptom.
For example, temporary diplopia may result from
- intoxication (due to excessive consumption of alcohol),
- certain head injuries, e.g. concussion,
- as a side-effect of some drugs (which, if suspected, should be reported
- tired and/or strained eye muscles, or
- "crossing" of one's eyes their own eyes intentionally.
As diplopia may be an initial indication of a serious
underlying condition, it is reason to seek prompt medical advice in case
of concern and especially if accompanied by other symptoms such as fatigue
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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