Abstract :Progressive Supranuclear Palsy (PSP) is a Parkinson-plus syndrome associated with a variety of
different clinical presentations. We describe the clinical and pathological features of the 7 major
phenotypes of PSP in addition to new information about the genetic causes of PSP. We also discuss
useful imaging tools, and review various management strategies. The classic form of PSP (PSPRichardson
syndrome) is more likely to be associated with postural instability, vertical gaze palsy,
akinesia and cognitive changes, compared to the milder variants of PSP. There are 6 other variants
of PSP besides PSP-RS, including PSP-parkinsonism, which can imitate Parkinson disease and can
respond to levodopa for the first 2-3 years. The Microtubular Associated Protein Tau (MAPT) gene
has a larger influence in PSP-RS than in PSP-parkinsonism. The rarer cortical variants of PSP (PSPprogressive
non-fluent aphasia, PSP-frontal temporal dementia and PSP-cortical basal syndrome)
can be mistaken for other neurodegenerative diseases, since the classic PSP signs may not appear
for months to years after the cortical signs present themselves. MRI and Diffusion Tensor Imaging
(DTI) scans are useful tools in assessing patients with signs of PSP. There is currently no disease
modifying therapy available for PSP, but many signs of PSP can be managed with symptomatic
treatments and various non-pharmacologic approaches.