Clinical pointers and radiological features in parkinsonian syndromes
| Clinical pointers | Radiological features | |
|---|---|---|
| Multiple system atrophy | ▸ May be indistinguishable from PD in early stages ▸ Jerky finger tremor related to mini-polymyoclonus ▸ ‘Strangulated’ dysarthria ▸ Axial/cranio-cervical levodopa-induced dyskinesia | ▸ Cerebellar atrophy ▸ T2 high signal in degenerating pontocerebellar fibres leading to ‘hot-cross bun’ sign (figure 2) ▸ T2 low signal in putamen with rim of increased signal on lateral edge |
| Progressive supranuclear palsy | ▸ Erect posture with good step size at presentation ▸ Frequent falls and injuries early in the disease course ▸ Slowed saccadic eye movements may be subtle in early disease | ▸ Midbrain atrophy (with ‘hummingbird’ sign on sagittal brainstem images, figure 3) ▸ 3rd ventricle dilatation |
| Corticobasal degeneration | ▸ Markedly asymmetrical rigid/akinetic/apraxic limb with relatively normal contralateral limb in early disease | ▸ Asymmetric fronto-parietal atrophy on MRI |
| Essential tremor | ▸ High-frequency tremor ▸ The tremor is postural and kinetic, and improves with rest ▸ Absent PD non-motor features ▸ Head and neck tremor ▸ May have a long and benign course | ▸ DaTscan is normal |
| Dystonic tremor | ▸ Thumb extension tremor ▸ Jerky tremor with flurries of tremor ▸ May be task-specific or task-exacerbated | ▸ DaTscan is normal |
| Vascular parkinsonism | ▸ Presents as gait disorder ▸ ‘Lower body’ parkinsonism with mild or absent upper body parkinsonism | ▸ Neuroimaging shows variable degrees of small-vessel ischaemic changes |
PD, Parkinson's disease.