Ptosis of the eyelids, adult: Drooping of the upper eyelids in adults, most commonly due to separation of the tendon of the lid-lifting (levator) muscle from the eyelid. This may occur with age, after cataract or other eye surgery, an injury, eye tumor or a complication of other diseases involving the levator muscle or its nerve supply, such as diabetes. If treatment is necessary, it is usually surgical. Sometimes a small tuck in the lifting muscle and eyelid can raise the lid sufficiently. More severe ptosis requires reattachment and strengthening of the levator muscle.