Commonly known as a droopy eyelid, ptosis may occur because of a
birth defect, muscle weakness in the eyelid, or abnormality in
nerves controlling the muscle.
Ptosis can be present at birth, called congenital ptosis, or come
about as a result of aging, injury or an after-effect of cataract or
other eye surgery. This condition can also be caused by a problem
with the muscles lifting the eyelid, called levators. Sometimes an
individual's facial anatomy causes difficulties with the levator
muscles

Children born with ptosis may require surgical correction of the lid if it covers the pupil. In some
cases, it may be associated with a crossed or misaligned eye. Left untreated, ptosis may prevent vision
from developing properly, resulting in amblyopia or lazy eye.
Patients with ptosis often have difficult blinking, which may lead to irritation, infection and eyestrain.
If a sudden and obvious lid droop is developed, you should consult your eye doctor immediately.
Ptosis does not usually improve with time, and nearly always requires corrective surgery. In most
cases, surgery is performed to strengthen or tighten the levator muscle and lift the eyelid. If the
levator muscle is especially weak, the lid and eyebrow may be lifted. Ptosis can usually be performed
with local anesthesia except with young children.