Movement Disorders USMLE Step 1 Practice Question
A 64-year-old man with a 2-year history of progressive ataxia, vertical supranuclear gaze palsy, and postural instability presents with newly documented bradykinesia and cogwheel rigidity. Vital signs: BP 145/88, HR 82, RR 16, Temp 37°C, SpO2 98%. He requires a cane for ambulation with multiple recent falls. Brain MRI shows midbrain atrophy. He denies tremor. He takes no antiparkinsonian medications. Which diagnosis best explains his presentation?
Answer choices
- ACerebellar atrophy from alcohol
- BParkinson disease with cerebellar involvement
- CProgressive supranuclear palsyCorrect answer
- DMultiple system atrophy with parkinsonism
- EFriedreich ataxia with late-onset features
- FCorticobasal degeneration
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