Ptosis (drooping upper eyelids)
When the edge of the eyelid falls and covers part of the pupil, it blocks the upper part of your vision. In severe cases, you may have to tilt your head back or lift the eyelid with a finger in order to see out from under the drooping lid.
This droopy eyelid, or ptosis, is generally age-related and occurs when the tendon that attaches the lifting muscle to the eyelid stretches, so the eyelid falls too low. Sometimes, there is a separation between the tendon and the muscle that lifts the eyelid.
It is not uncommon to develop a drooping eyelid after cataract surgery or long-standing contact lens use. A similar drooping may also affect the eyebrow and is known as brow ptosis — the word simply means downward displacement.
Ptosis can also be present at birth, or congenital. This form of the condition is often caused by poor development of the muscle that lifts the eyelid. If uncorrected, normal vision may fail to develop and the child may adopt an abnormal posture, with his or her head tilted backwards.