Neurodegenerative Diseases USMLE Step 1 Practice Question
A 46-year-old man presents with a 2-week history of right-sided neck pain following a motor vehicle accident. Vital signs show BP 138/82, HR 82, RR 16, and normal temperature. Examination reveals mild right ptosis, miosis, and anhidrosis of the right face. Brain MRI demonstrates a right lateral medullary infarct. Cranial nerves II through XII are otherwise intact. He denies diplopia or dysphagia. Which of the following best explains this clinical presentation?
Answer choices
- ALesion of the optic chiasm
- BCompression of the oculomotor nerve by aneurysm
- CLesion of the sympathetic pathway to the eye and faceCorrect answer
- DOcclusion of the central retinal artery
- EDamage to the facial nerve nucleus
- FInternal carotid dissection causing post-ganglionic Horner syndrome
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