Progressive supranuclear palsy (PSP)

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disorder representing an important differential diagnosis of Parkinson's disease. Most of the patients suffering from PSP show characteristic symptoms (Richardson syndrome) comprising a symmetric akinetic rigid Parkinson syndrome, vertical gaze palsy, early falls, dysphagia and dysarthria and poor responsiveness to levodopa. Recently, it was recognized that there are also atypical patients presenting with an asymmetric Parkinson syndrome with tremor and moderate levodopa responsiveness. The latter syndrome much more resembles Parkinson's disease (PSP-P). The classical gaze palsy may be absent. We suggest that patients with presumed Parkinson's disease who show limited or decreasing levodopa responsiveness during the course of their illness may suffer form PSP-P.