Ptosis is drooping of the upper eyelid. The upper lid descends and in severe cases starts to obstruct vision. Most cases occur as a result of stretching of the tissues that lift the lid due to ageing. This process can be accelerated by contact lens wear. Less common causes include impairment of the nerve supply to the muscles that elevate the eyelid (levator muscle: third cranial nerve, or Muller’s muscle: sympathetic nerves, Horner’s syndrome), interference with the connection between nerve and muscle as in myasthenia gravis, defective muscles as in congenital ptosis (present from birth) or muscular dystrophy (onset later in life), or large masses or folds of skin that pull the lid downwards.
Clinical Features
Drooping of the upper eyelid, often worse towards end of day
Reduction in upper field of vision if severe
Hollowed out upper eyelid appearance in age-related ptosis
Additional eye features may be present depending on underlying cause:
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Double vision eg with third cranial nerve palsy, myasthenia gravis
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Large pupil with third cranial nerve palsy, small pupil with Horner’s syndrome
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Impaired movements of the eye eg with congenital ptosis, muscular dystrophy or myasthenia gravis
Congenital ptosis sufficient to cover the eye may lead to impaired visual development (amblyopia)
Management
See ophthalmologist with experience in oculoplastic surgery. Sudden onset ptosis and severe congenital ptosis needs to be seen urgently.
Where the cause is stretching of the eyelid opening tissues surgery to tighten and strengthen these tissues is effective at lifting the lid and is normally carried out under a local anaesthetic as a day case.
Defective muscles may also respond to similar surgery as long as there is adequate residual power in the muscles. If not it may be necessary to provide a connection to the eyelid from the eyebrow so that raising the eyebrows enables eyelid opening. This is effective but rarely needed. Congenital ptosis needs to be corrected urgently if occluding the pupil or impairing visual development. Otherwise surgery is usually deferred until age 3-5
Other causes of ptosis will require specific investigation and treatment. (See our specialist practice section)
