Braak's Unfinished Hypothesis: A Clinicopathological Case Report of α-Synuclein Peripheral Neuropathy Preceding Parkinsonism by 20 Years.

This case provides important in vivo clinical correlation for the Braak hypothesis, extending its scope beyond idiopathic PD. A growing body of evidence supports the α-synuclein spreading hypothesis that posits the pathologic process begins in the peripheral nerves and spreads trans-synaptically to the CNS in an ascending pattern.