Ptosis is the medical name for the drooping of the upper eyelid, which can happen in one or both eyes.
What is ptosis?
A low upper lid can interfere with vision by affecting the top part of your visual field. You might also have difficulty keeping your eyelids open, eyestrain or eyebrow ache (from the increased effort needed to raise your eyelids), and fatigue, especially when reading. For some patients, ptosis poses a cosmetic problem.
Ptosis can either be present at birth (congenital), or appears later in life (acquired), following long-term contact lens wear, trauma, after cataract surgery or other eye operations. There are less common causes of a droopy eyelid, such as problems with the nerves or muscles.
What causes ptosis?
Congenital ptosis affects a child from birth and is commonly due to a defect in the levator muscle which raises the eyelids. It can affect one or both lids.
Although this can be purely a cosmetic problem, it can also prevent normal visual development, so surgery to correct the lid position is sometimes necessary.
In Marcus Gunn 'jaw-winking' ptosis, the droopy eyelid rises when the jaw is opened due to an abnormal connection of the nerves. This condition is usually noticed only in small children and affects one eyelid. Surgery may be necessary. Operating on the affected eyelid could cause the unaffected eyelid to also droop. Therefore you may need surgery on both eyelids. This will be explained further by your doctor.
Acquired ptosis affects patients later in life and can be due to a defect in the muscles or nerves of the eyelid which can occur with simple ageing or injury. A weakness in the eyelid muscles can occur in some rare muscle conditions such as myasthenia gravis or myotonic dystrophy. Paralysis of the nerves supplying the eyelid can cause it to droop as in a third nerve palsy (a type of stroke). The eyelid can also droop if weighed down by a large cyst or swelling.
What does ptosis surgery involve?
Ptosis surgery usually involves shortening the muscles or tendons that raise the lid. The muscle or tendon is reattached to your eyelid using sutures, which are buried under the skin. The sutures might be visible on the skin of your eyelids, but are removed around one week after surgery.
Occasionally, the lid is suspended from the brow in order to raise it. This is done using either tendon from your thigh taken via an incision just above the knee, or using an artificial material. Brow lift surgery is often done on both sides at the same time in order to achieve a better cosmetic result. The number of stitches in your leg can vary but this is usually removed after ten to fourteen days. This can be done by your own GP.