Abstract: Objective To investigate the features of magnetic resonance imaging (MRI) in the brain of patients with progressive supranuclear palsy (PSP). Methods 17 patients with PSP and 30 patients with Pakinson disease (PD) were retrospectively studied with MRI. Results The atrophy of the midbrain tegmentum and hummingbird sign were demonstrated in all of the PSP patients studied, but were only flatness observed in 13% of PD patients. The area of the midbrain and the ratio of midbrain versus pons areas in the patients with PSP were significantly smaller than in those with PD. The average of midbrain transverse diameter in PSP was smaller than those in PD, but an overlap was observed. Tegmental T₂ hyperintensity had lower sensitivity. Conclusion MRI may be useful to distinguish PSP from PD.

Key words: progressive supranuclear palsy, Parkinson disease, magnetic resonance imaging