Issues to overcome include developing tracers for intracellular targeting with ideal lipophilicity and tracer selectivity for α-syn over amyloid and tau aggregates.369,370 More recently, however, a newly developed α-syn PET tracer, 18F-ACI-12589, was shown to bind to basal ganglia and cerebellar white matter in a small cohort, although this was confined to MSA patients.371 Larger studies examining diagnostic accuracy for distinguishing PD from MSA will be critical. Here, MAPT is linked to multiple system atrophy.