Demyelinating Diseases USMLE Step 1 Practice Question
A 34-year-old woman presents with acute monocular vision loss and pain with eye movements. Vital signs: BP 118/76, HR 88, RR 16, Temp 37.2°C, SpO2 98%. Examination reveals a relative afferent pupillary defect. Brain MRI is normal; however, orbital MRI demonstrates T2 hyperintensity and gadolinium enhancement of the optic nerve. She denies headache, weakness, or sensory changes. She takes no chronic medications. Which diagnosis is most likely?
Answer choices
- AMultiple sclerosis
- BOptic neuritisCorrect answer
- CAcute disseminated encephalomyelitis
- DLeber hereditary optic neuropathy
- ENeuromyelitis optica spectrum disorder
- FOrbital lymphoma
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