Demyelinating Diseases USMLE Step 1 Practice Question
A 30-year-old woman presents with acute-onset diplopia and gait imbalance. Vital signs: BP 118/76, HR 88, RR 16, Temp 37.2°C, SpO2 98%. On neurologic exam, leftward gaze produces failure of right eye adduction with left eye abducting nystagmus; convergence remains intact. Brain MRI reveals periventricular T2 hyperintensities. She denies prior neurologic symptoms. Which of the following best explains these findings?
Answer choices
- AOptic neuritis
- BTransverse myelitis
- CAmyotrophic lateral sclerosis
- DMultiple sclerosis
- EInternuclear ophthalmoplegia from medial longitudinal fasciculus lesionCorrect answer
- FSixth nerve palsy from pontine glioma
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