Cerebrovascular Disease USMLE Step 1 Practice Question
A 33-year-old woman presents with progressive burning injuries to both hands sustained while cooking that she did not notice. Vital signs show BP 118/76, HR 82, RR 16, Temp 37.2°C, SpO2 98% on room air. Neurologic examination reveals bilateral loss of pain and temperature sensation over the shoulders and upper extremities with preserved vibration sense and normal strength. Brain MRI shows central cord signal abnormality. She denies recent trauma or fever. Which of the following is the most likely explanation?
Answer choices
- ASelective damage to lateral corticospinal tracts
- BCavitation of the central spinal cord affecting crossing spinothalamic fibersCorrect answer
- CHemisection of the spinal cord
- DDestruction of anterior horn cells only
- ECompression of dorsal columns in the cervical cord
- FDemyelination of peripheral sensory nerves affecting all sensory modalities equally
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.