A drooping eyelid is also called ptosis or blepharoptosis. In this condition, the border of the upper eyelid falls to a lower position than normal. In severe cases, the drooping eyelid can cover all or part of the pupil and interfere with vision.
Ptosis can affect one or both eyes. It may be present at birth (congenital ptosis), or it may develop gradually over decades. Sometimes ptosis is an isolated problem that changes a person's appearance without affecting vision or health. In other cases, however, it can be a warning sign that a more serious condition is affecting the muscles, nerves, brain or eye socket. Ptosis that develops over a period of days or hours is more likely to signify a serious medical problem.
What are the causes of ptosis or drooping eyelid?
- Congenital ptosis: In this condition, an infant is born with ptosis because of a developmental problem involving the muscle that raises the upper eyelid (levator muscle). In approximately 7 out of 10 cases, the condition affects only one eye. If the drooping eyelid obscures part of the baby's visual fields, surgery must be done to correct the problem early in life to prevent permanent loss of vision.
- Aponeurotic ptosis: Aging is the most common cause of ptosis that is not present at birth. In senile ptosis, the long-term effects of gravity and aging cause stretching of a wide, tendon-like tissue that helps the levator muscle lift the eyelid. Although both eyes usually are affected, drooping may be worse in one eye.
- Myasthenia gravis: Ptosis can be one of the first symptoms of myasthenia gravis, a rare disorder that affects the ways muscles respond to nerves. Myasthenia gravis can cause progressive muscle weakness, not only in the eyelids but also in the facial muscles, arms, legs and other parts of the body.
- Muscle diseases: Ptosis can be a symptom of an inherited muscle disease called oculopharyngeal muscular dystrophy that affects eye motion and can cause difficulty swallowing. In younger adults, ptosis can be caused by a group of muscle illnesses called progressive external ophthalmoplegia, which cause ptosis in both eyes, problems with eye movement, and sometimes other muscle symptoms that involve the throat or heart muscle.
- Nerve problems: Because the eye muscles are controlled by nerves that come from the brain, conditions that injure the brain or its cranial nerves sometimes can cause ptosis. These conditions include stroke, brain tumour, a brain aneurysm (a grapelike swelling on a blood vessel inside the brain), and nerve damage related to long-term diabetes. Another cause of ptosis is Horner's syndrome, which also can cause an abnormally small pupil and loss of the ability to sweat - on half the face. One particularly dangerous cause of Horner's syndrome is a cancerous tumour located at the top portion of the lungs.
- Local eye problems: In some cases, an eyelid droops because of an infection or tumour of the eyelid, a tumour inside the eye socket, or a blow to the eye.
Ophthalmologists assess the severity of eyelid droop by taking precise measurements of the eyelid and eye opening. You can screen for the problem yourself by looking straight ahead in a mirror. As you look at your eye, a sizable part of your iris (the eye's coloured circle) should be visible above your pupil, and no part of the pupil itself should ever be covered by the eyelid.
If you have ptosis, the drooping eyelid narrows your eye's opening, which makes your affected eye appear smaller than normal. You also may lose the crease (fold of skin) that normally lies between your upper eyelid and eyebrow. If ptosis covers your pupil and limits your vision, you may try to compensate unconsciously by raising your eyebrows. This can cause tension headaches and give your eyes an odd, surprised appearance. You also may tilt your chin up and look down your nose as a way of seeing out from under your eyelid's lower margin.
If you have simple, uncomplicated ptosis, you won't have any other symptoms. If your ptosis is caused by a more serious medical problem, however, you may have additional symptoms that are related to the underlying illness.
How ptosis or drooping eyelid is diagnosed?
If you notice that both of your upper eyelids have become progressively droopy with age, then you probably have simple age-related ptosis. Some old photographs usually can confirm the diagnosis because they prove that your drooping eyelids have worsened gradually over the years.
In other cases of ptosis, an ophthalmologist must diagnose the problem. The ophthalmologist will begin by reviewing all of your symptoms, not just your eyelid complaints. This review includes any symptoms of double vision, muscle fatigue or weakness, difficulty speaking or swallowing, headache, or tingling or numbness anywhere in your body. Your doctor also will review your past medical history and ask about any family history of ptosis or inherited muscle diseases.
Then, your ophthalmologist will do a physical examination, a neurological examination, and a thorough examination of your eye. If your eye specialist finds anything abnormal, special diagnostic tests are necessary. For example, you may need a computed tomography (CT) scan or magnetic resonance imaging (MRI) scan if you have signs of a neurological problem or if your eye examination reveals evidence of a mass or swelling inside your eye socket.
If age-related ptosis blocks your vision or seriously affects your appearance, a plastic surgeon usually can correct the problem by surgically raising your eyelid. In most adult patients, this is an outpatient procedure that is done under local anaesthesia. Local anaesthesia is preferred over general anaesthesia because it allows the surgeon to adjust the position of your eyelids while your eyes are open.
If your baby is born with severe congenital ptosis, your ophthalmologist probably will recommend prompt corrective surgery because early treatment reduces the risk of permanent vision damage. If your child has milder ptosis without impaired vision, however, the ophthalmologist may suggest waiting until the child is 3 to 5 years old to correct the drooping eyelid. During childhood, eyelid surgery is performed under general anaesthesia.
If you have ptosis that is caused by a muscle disease, neurological problem or local eye problem, your ophthalmologist will treat the illness. In some cases, this treatment either improves the drooping eyelid or keeps it from getting worse.
Ptosis or drooping eyelid surgery outlook
In most cases, the prognosis is good. Surgery usually can correct the drooping eyelid in children with congenital ptosis and adults with age-related ptosis. In some cases, corrective surgery causes the eyes to remain open slightly during sleep, so a night-time lubricant is applied to the eyes to prevent drying.