Abnormal drooping of one or both upper eyelids
Drooping of the upper eyelid due to weakness of the muscle that raises it is called ptosis. The condition may be the result of a problem with the muscle or nerve that controls the eyelid. The sagging lid may partly or totally close the eye. One or both eyes may be affected.
Ptosis is occasionally present from birth. If a baby’s eyelid droops and it covers the pupil, his or her vision may not develop normally (see Amblyopia) and early treatment is vital.
Ptosis in adults can occur as a part of the aging process, or it may be a symptom of myasthenia gravis, which causes progressive muscle weakness. If ptosis starts suddenly, it may be due to a brain tumour or a defective blood vessel in the brain. If you develop ptosis, see your doctor to rule out a serious underlying disorder.
Ptosis in babies can be corrected by surgically tightening the eyelid muscle. If treatment is carried out early, the child’s vision should develop normally.
In adults, surgery for ptosis should be carried out only after any possible significant underlying disorders have been ruled out. Surgery is very effective for ptosis caused by the aging process.
From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.