Overview
Progressive supranuclear palsy (PSP) is a degenerative disorder characterised by features of Parkinson’s disease, impairment of eye movement, and cognitive dysfunction. It is a type of Parkinson-plus syndrome. Degeneration occurs in the basal ganglia, brainstem, frontal lobes and limbic system, cerebellum, and spinal cord.
Epidemiology
- PSP is rare with an incidence of around 18 per 100,000 in those aged >70 years
- The mean age of onset is 65 years
Features
- Parkinsonism – features remembered using TRAP:
- Tremors
- Rigidity
- Akinesia/bradykinesia
- Postural instability
- Supranuclear (relating to vertical gaze) ophthalmoplegia (ophthalmo- eyes, plegia¬- paralysis):
- Impaired vertical gaze – downwards gaze is worse than upwards
- Patients may have difficulties walking downstairs
- Cognitive impairment – mainly frontal lobe dysfunction:
- Behavioural abnormalities:
- Apathy
- Disinhibition (inability to withhold inappropriate/unwanted behaviour)
- Dysphoria (unease/dissatisfaction)
- Behavioural abnormalities:
- Poor response to levodopa
Diagnosis
The diagnosis of PSP is made clinically by a specialist. Other investigations may be performed to rule out other conditions, however, no tests are diagnostic.
