Manual MRI morphometry in Parkinsonian syndromes

ABSTRACT Background : Several morphometric magnetic resonance imaging parameters may serve for differential diagnosis of parkinsonism. The objective of this study was to identify which performs best in clinical routine. Methods : We acquired multicentric magnetization‐prepared rapid gradient echo sequences in patients with Parkinson's disease (n=204), progressive supranuclear palsy (n=106), multiple system atrophy‐cerebellar, (n = 21); multiple system atrophy‐parkinsonian (n = 60), and healthy controls (n = 73), performed manual planimetric measurements, and calculated receiver operator characteristics with leave‐one‐out cross‐validation to propose cutoff values. Results : The midsagittal midbrain area was reduced in PSP versus all other groups ( P < 0.001). The midsagittal pons area was reduced in MSA‐cerebellar, MSA‐parkinsonian, and PSP versus PD patients and healthy controls ( P < 0.001). The midbrain/pons area ratio was lower in PSP ( P < 0.001) and higher in MSA‐cerebellar and MSA‐parkinsonian versus PD and PSP ( P < 0.001). Conclusions : The midsagittal midbrain area most reliably identified PSP, the midsagittal pons area MSA‐cerebellar. The midbrain/pons area ratio differentiated MSA‐cerebellar and PSP better than the magnetic resonance‐Parkinson index. © 2017 International Parkinson and Movement Disorder Society