Rolf Hassler (1914–1984) was a German pathologist who made important discoveries on the pathophysiology and treatment of Parkinson's disease (PD).
[1] In 1938 he published the autopsies of PD patients that showed while the striatum and globus pallidus were mostly unaffected and the main affected structure was the substantia nigra pars compacta; it lost many neurons and also held abundant Lewy bodies.
Such findings confirmed Konstantin Tretiakoff's theories, who in 1919 had reported that the substantia nigra was the main cerebral structure affected.
[1] Hassler later was the director of the Max-Planck-Institut für Hirnforschung at Frankfurt am Main where he continued his studies on PD, becoming a pioneer in surgery for tremors.
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