- double vision
* * *or diplopiaPerception of two images of an object, usually caused by temporary or permanent eye-muscle paralysis.Normally, the brain fuses slightly different images from each eye by matching corresponding points on each retina. When an eye muscle is paralyzed, the image falls at a different point and the images do not correspond. Double vision may be an early symptom of botulism or myasthenia gravis and occurs in other infections, head injuries, and nerve or muscle disorders.
* * *also called diplopiaperceiving of two images of a single object.Normal binocular vision results from the brain's fusion of slightly different images from each eye (eye, human), with points on the retina of each eye corresponding to points on the retina of the opposite eye. Binocular diplopia occurs when the eyes are not properly aligned, and the image of an object that projects onto one retina does not fall spatially to the matching point on the other retina. In such a situation, the double image is eliminated when either eye is covered. It is commonly caused by temporary or permanent paralysis or restriction of one or more of the external eye muscles (muscle). The orientation of the double image is determined by the particular muscle (sometimes more than one muscle) that is not working properly.Causes of binocular diplopia include myasthenia gravis, inflammatory (inflammation) processes, thyroid (thyroid gland) eye disease (Graves ophthalmopathy), small blood vessel disease (e.g., diabetes mellitus), trauma, infections, and various tumours (tumour). These processes usually induce diplopia by impairing the external eye muscles themselves or the nerves that directly or indirectly control their function. However, an underlying cause of diplopia is not always found. Frank displacement of the eyeball, via large orbital fractures or a mass pressing on the eyeball, can also cause double vision.The treatment for binocular double vision varies depending on the cause, severity, and duration. Many cases of diplopia resolve on their own and require only temporary patching of one eye to eliminate the offending second image. People with permanent diplopia may benefit from prisms placed in eyeglasses or from surgical realignment of the eyes. Of course, treatment of underlying diseases or injuries is also essential.Misalignment of the eyes in early childhood is a special situation. It usually does not result in symptomatic diplopia, as the child's developing brain suppresses the second image. Without correction, this often leads to amblyopia and permanent vision loss in the “suppressed” eye.Monocular diplopia differs from binocular diplopia in that the double vision remains present when the nonaffected eye is covered. Monocular diplopia is due to abnormalities in the structure of the eyeball itself, most notably the lens and cornea. Treatment is directed at correcting the abnormality.
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Double vision — refers to Diplopia, the perception of two images from a single object.Double vision may also refer to: *Double Vision, a Malaysian TV network. *Double Vision (Foreigner album), a 1978 album by Foreigner *Double Vision (Bob James and David Sanborn … Wikipedia
Double Vision — Données clés Titre original Shuang tong Réalisation Kuo Fu Chen Scénario Kuo Fu Chen Chao Bin Su Acteurs principaux David Morse Tony Leung Ka fai Pays d’origine … Wikipédia en Français
Double Vision — („Doppeltsehen“) ist der Name eines aus Spanien kommenden Eurodance Duos, siehe Double Vision (Band) eines taiwanischen Filmes, siehe Double Vision – Fünf Höllen bis zur Unsterblichkeit Diese Seite ist eine Begriffsklärung zur Unterscheid … Deutsch Wikipedia
double vision — n DIPLOPIA * * * see diplopia * * * diplopia … Medical dictionary
double vision — n [U] a medical condition in which you see two objects instead of one all the time, for example after an accident … Dictionary of contemporary English
double vision — noun uncount a medical condition in which you see a single object as two objects … Usage of the words and phrases in modern English
double vision — n. DIPLOPIA … English World dictionary
double vision — noun visual impairment in which an object is seen as two objects diplopia often disappears when one eye is covered • Syn: ↑diplopia • Hypernyms: ↑visual impairment, ↑visual defect, ↑vision defect, ↑visual disorder * * * … Useful english dictionary
double vision — N UNCOUNT If someone is suffering from double vision, they see a single object as two objects, for example because they are ill or have drunk too much alcohol … English dictionary
double vision — noun a disorder of vision, (diplopia), in which a single object is seen as two … Wiktionary