Demyelinating Diseases USMLE Step 1 Practice Question
A 27-year-old woman with no prior neurologic history presents with acute onset of diplopia and facial numbness. Vital signs show BP 118/76, HR 88, RR 16, temperature 37.2°C, SpO2 98% on room air. Examination reveals bilateral internuclear ophthalmoplegia and facial sensory loss. Brain MRI demonstrates bilateral brainstem T2-hyperintense lesions. CSF analysis shows normal glucose and protein. She denies fever or recent infections. Which of the following is the most likely diagnosis?
Answer choices
- AVertebrobasilar insufficiency
- BMultiple sclerosisCorrect answer
- CBrainstem glioma
- DLyme disease
- EMiller Fisher syndrome
- FCentral pontine myelinolysis
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