MRI of progressive supranuclear palsy, corticobasal degeneration and multiple system atrophy.

The characteristics of progressive supranuclear palsy (PSP), corticobasal degeneration (CBD) and multiple system atrophy (MSA) on routine magnetic resonance imaging (MRI) are reviewed. In PSP, atrophy of the midbrain tegmentum, truncus of corpus callosum and anterior cingulate cortex was seen on midsagittal plane MRI. These findings probably relate to supranuclear gaze palsy, motor programming dysfunction and emotional dysfunction. In CBD, asymmetric frontoparietal atrophy is usually seen, which could be the basis of focal signs. In MSA, putaminal and pontine involvements are represented by the hyperintense rim and ,hot-cross bun' signs on MRI. These would be closely linked via the premotor and motor cortex, which supervise motor execution. MRI findings mirror the clinical signs and symptoms in atypical parkinsonism. [ABSTRACT FROM AUTHOR]