Ptosis

What is ptosis?

Ptosis refers to a drooping of the eyelids. It can occur to varying degrees and can affect the visual field when it covers the pupil or part of it.

What causes ptosis?

This can be due to a number of causes of ptosis, but most commonly it is due to age related changes of the eyelid and stretching of the tendon sheet (aponeurosis) which pulls up the upper eyelid.

Exacerbating factors include long term contact lens use and eye surgery. The latter occurs as during eye surgery, a speculum is used, which stretches the eyelid to hold it open.

What are the symptoms of having a ptosis?

It can become a problem because of the appearance; a change in head posture – having to tip up the head to see under the lids; and because of loss of the superior visual field as the lid covers the top part of the vision. Field of vision is important for mobility, sport, day-to-day activities and in particular there is a specific visual field requirement for driving.

Are any tests required to investigate ptosis?

Loss of visual field can be demonstrated by means of a visual field test. If it affects the central 20 degrees, the eyelid may affect the driving vision as there is a requirement for this field of vision to be unaffected by the DVLA.

A number of clinical measurements of the eyelids and eye movements are taken to exclude other conditions that can cause ptosis such as a Horner’s syndrome, third cranial nerve palsy or myasthenia gravis. A ptosis can also be simulated if the eyeball is sunken in for example in the sick sinus syndrome. If any of the clinic tests are abnormal, it may be that a blood test or MRI or CT scan of the head may be requested to exclude any underlying pathology.

What treatment is available for ptosis?

The treatment for most ptosis is surgical. On occasion, there are some conditions such as myasthenia gravis where medication is required. There are a number of variations in how the surgery is performed and this can be done under local or general anaesthetic.