Neuroanatomy USMLE Step 1 Practice Question
A 62-year-old man with hypertension and hyperlipidemia presents to the emergency department with acute onset facial drooping on the right side. On examination, he is unable to close his right eye, has hyperacusis in the right ear, and demonstrates loss of taste sensation on the anterior two-thirds of the right tongue. Strength in his right arm and leg is 5/5. An MRI brain with diffusion imaging shows an acute ischemic stroke in the left lower precentral gyrus. Which of the following structures is most likely responsible for the observed clinical findings?
Answer choices
- ALeft facial motor cortex (Brodmann area 4)Correct answer
- BLeft facial nucleus in the pontomedullary junction
- CLeft geniculate ganglion
- DRight facial nerve at the stylomastoid foramen
- ELeft corticobulbar tract in the internal capsule
- FRight trigeminal nerve (CN V)
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