Neuroanatomy USMLE Step 1 Practice Question
A 28-year-old woman with a 2-year history of pulmonary sarcoidosis presents with acute-onset right-sided facial weakness. On examination, she has complete weakness of all muscles on the right side of her face, including the frontalis muscle—she cannot wrinkle her forehead or close her right eye completely. She denies ear pain, hearing loss, or vesicular rash. Serum ACE level is elevated at 72 U/L (normal <25 U/L). Brain MRI shows nonspecific T2 hyperintensity in the right cerebellopontine angle. Which of the following anatomical locations best explains her clinical presentation?
Answer choices
- ALeft motor cortex (Brodmann area 4)
- BRight corticobulbar tract in the pons
- CRight internal capsule
- DRight facial nerve (CN VII) at or distal to the stylomastoid foramenCorrect answer
- ERight facial nerve nucleus in the medulla
- FRight geniculate ganglion
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