Neuroanatomy USMLE Step 1 Practice Question
A 45-year-old woman presents with acute onset of loss of pain and temperature sensation over her right arm and shoulder with preserved motor strength. She concurrently reports loss of pain sensation on the left side of her face. Vital signs: BP 145/92, HR 88, RR 16, Temp 37.2°C, SpO2 98%. MRI brain shows acute infarction in the medulla. Proprioception remains intact. Which brainstem structure is most likely damaged?
Answer choices
- ARight medial medulla
- BRight lateral medullaCorrect answer
- CRight midbrain
- DRight pontine tegmentum
- ELeft lateral medulla
- FRight medullary pyramid
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