Cerebrovascular Disease USMLE Step 1 Practice Question
A 63-year-old man with hypertension presents after sudden collapse. Vital signs: BP 168/94 mmHg, HR 92/min, RR 16/min, temp 37.2°C. He is intubated and awake. Examination reveals preserved vertical eye movements to command but complete paralysis of all four limbs and lower facial muscles. Sensation to pinprick remains intact throughout. Recent aspirin use noted. MRI shows acute midline pontine infarction. Which vascular lesion best explains this locked-in syndrome presentation?
Answer choices
- ARight middle cerebral artery infarction
- BCervical central cord syndrome
- CBilateral medial medullary infarction
- DPontine infarction due to basilar artery occlusionCorrect answer
- ESubthalamic nucleus hemorrhage
- FMidbrain infarction due to posterior cerebral artery occlusion
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