FIG 3.

MR imaging in MSA and APDs. ADC, apparent diffusion coefficient; APDs, atypical parkinsonian disorders; DNH, dorsal nigral hyperintensity; FA, fractional anisotropy; HC, healthy control; MCP, middle cerebellar peduncle; MD, mean diffusivity; MR, magnetic resonance; MRI, magnetic resonance imaging; MRPI, Magnetic Resonance Parkinsonism Index; MSA, multiple system atrophy; NM, neuromelanin; PD, Parkinson's disease; PSP, progressive supranuclear palsy; SWI, susceptibility weighted imaging; VM, white matter; GM, gray matter; M/P, midbrain‐to‐pons ratio.