DefinitionPtosis is also called "drooping eyelid." It is caused by weakness of the muscle responsible for raising the eyelid, damage to the nerves that control those muscles, or looseness of the skin of the upper eyelids.Alternative NamesDrooping eyelidsCauses, incidence, and risk factorsDrooping eyelid can be caused by the normal aging process, a congenital abnormality (present before birth), or the result of an injury or disease.Risk factors include aging, diabetes, stroke, Horner syndrome, myasthenia gravis, and a brain tumor or other cancer, which can affect nerve or muscle reactions.SymptomsDrooping of one or both eyelidsIncreased tearingIf ptosis is severe, interference with vision.Signs and testsA physical examination to determine the causeSpecial tests may be done to evaluate suspe