Idiopathic REM sleep behavior disorder (iRBD) is a marker of early neurodegenerative synucleinopathy. Nigrostriatal dopaminergic dysfunction is often considered the primary pathologic mechanism behind motor symptoms; however, other mechanisms have been proposed. The aim of this study was to identify patients with iRBD who demonstrated discordance between motor testing and abnormal nigrostriatal uptake and to characterize these patients.
Zatti et al. (Tue,) studied this question.