Diplopia, commonly known as double vision, is the simultaneous perception of two images of a single object that may be displaced horizontally, vertically, or diagonally (i.e. both vertically and horizontally) in relation to each other. It is usually the result of impaired function of the extraocular muscles (EOM's), where both eyes are still functional but they cannot converge to target the desired object. Problems with EOM's may be due to mechanical problems, disorders of the neuromuscular junction, disorders of the cranial nerves (III, IV, and VI) that stimulate the muscles, and occasionally disorders involving the supranuclear oculomotor pathways or ingestion of toxins.
Diplopia is often one of the first signs of a systemic disease, particularly to a muscular or neurological process, and it may disrupt a person’s balance, movement, and/or reading abilities.
Famous quotes containing the words double and/or vision:
“The worst feature of this double consciousness is, that the two lives, of the understanding and of the soul, which we lead, really show very little relation to each other; never meet and measure each other: one prevails now, all buzz and din; and the other prevails then, all infinitude and paradise; and, with the progress of life, the two discover no greater disposition to reconcile themselves.”
—Ralph Waldo Emerson (1803–1882)
“You had such a vision of the street
As the street hardly understands;
Sitting along the bed’s edge, where
You curled the papers from your hair,
Or clasped the yellow soles of feet
In the palms of both soiled hands.”
—T.S. (Thomas Stearns)