Richardson observed an unusual clinical syndrome in the 1950s, which he later designated as progressive supranuclear palsy (PSP). In 1963, Richardson et al<sup>62 Richardson J.C., Steele J., Olszewski J. Supranuclear ophthalmoplegia, pseudobulbar palsy, nuchal dystonia and dementia: A clinical report on eight cases of “heterogenous system degeneration” Trans Am Neurol Assoc 1963 ;  88 : 29-25

Cliccare qui per andare alla sezione Riferimenti</sup> reported a series of eight cases of PSP, parkinsonism in combination with supranuclear palsy. PSP is also referred to as Steele-Richardson-Olszewski syndrome, an eponym that was first used by Barbeau in 1965.<sup>4 Barbeau A. Degenerescence plurisystematisee du nevraxe. Syndrome de Steele-Richardson-Olszewski Un Med Can 1965 ;  94 : 715-718

Cliccare qui per andare alla sezione Riferimenti</sup> Over the past 25 years, although knowledge of this disorder has gradually improved, its cause is still unknown, pathogenesis is unclear, and there is still no definitive treatment for this disorder. This article reviews the epidemiology, clinical features, diagnostic criteria, neuropathology, neuroimaging, and treatment of PSP.