Neuroanatomy USMLE Step 1 Practice Question
A 45-year-old woman presents with sudden-onset weakness of the right lower extremity and loss of pain and temperature sensation on the left side of her body below the neck. Vital signs: BP 158/92 mmHg, HR 88, RR 16, Temp 37°C, SpO2 98%. MRI demonstrates an acute infarct in the left medulla. Neurologic exam reveals intact right facial sensation. Which of the following tracts is most likely damaged?
Answer choices
- AMedial longitudinal fasciculus and corticobulbar tract
- BLateral corticospinal tract and spinal trigeminal nucleus
- CMedial lemniscus and hypoglossal nerve fibers
- DSpinocerebellar tract and vestibulospinal pathway
- ELateral spinothalamic tract and pyramidal fibersCorrect answer
- FAnterior spinothalamic tract and medial lemniscus
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