Devic’s disease /dəvēks′/ [Eugène Devic, French physician, 1869–1930] , combined, but not usually clinically simultaneous, demyelination of the optic nerve and the spinal cord, marked by diminution of vision and sometimes blindness, flaccid paralysis of the extremities, and sensory and genitourinary disturbances. Should not be confused with multiple sclerosis.