Neurodegenerative Diseases USMLE Step 1 Practice Question
A 27-year-old woman presents with acute left gaze palsy; the right eye fails to adduct while the left eye demonstrates nystagmus. She reports transient monocular vision loss three months prior and right-sided sensory loss six months ago. Vital signs: BP 118/76, HR 82, RR 16, Temp 37°C, SpO2 98%. Brain MRI reveals T2 hyperintense lesions in the optic nerve and periventricular white matter. CSF analysis shows oligoclonal bands. She denies fever or recent infections. Which diagnosis best explains these recurrent, anatomically distinct neurologic episodes?
Answer choices
- AParkinson disease
- BMultiple sclerosisCorrect answer
- CMyasthenia gravis
- DPosterior communicating artery aneurysm
- ETemporal arteritis
- FNeurosarcoidosis
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