Neuroanatomy USMLE Step 1 Practice Question
A 38-year-old man presents with acute inability to look to the right, right facial droop, and right arm and leg weakness. Vital signs show BP 158/92 mmHg, HR 88, RR 16, temperature 37.2°C, SpO2 98% on room air. Brain MRI demonstrates a left ventromedial midbrain infarct. Laboratory studies reveal elevated fasting glucose at 126 mg/dL. He denies diplopia. Which of the following structures is damaged?
Answer choices
- ARight superior colliculus and right oculomotor nerve
- BLeft medial lemniscus and left rubrospinal tract
- CLeft trigeminal nerve and left spinothalamic tract
- DRight abducens nerve and right corticospinal tract
- ELeft oculomotor nerve and corticospinal tractCorrect answer
- FLeft trochlear nerve and left rubrospinal tract
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