Neurodegenerative Diseases USMLE Step 1 Practice Question
A 70-year-old man with hypertension presents with sudden-onset violent flinging movements of his left arm and leg. Vitals: BP 158/92 mmHg, HR 88, RR 16, temp 37.2°C, SpO2 98%. He remains alert and oriented with intact strength throughout. MRI reveals a small lacunar infarct in the right diencephalon; diffusion-weighted imaging confirms acute ischemia. No sensory deficits are noted. Which of the following structures is most likely involved?
Answer choices
- ARed nucleus
- BSubthalamic nucleusCorrect answer
- CGlobus pallidus internus
- DSubstantia nigra pars compacta
- ECaudate nucleus
- FContralateral putamen
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