or diplopia
Perception 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.