Neurodegenerative Diseases USMLE Step 1 Practice Question
A 6-year-old boy presents with progressive morning headaches, vomiting, and ataxic gait for 3 weeks. Vital signs show BP 128/82 mmHg, HR 92 bpm, RR 20/min, temperature 37.2°C, SpO2 98% on room air. MRI reveals a 3 cm posterior fossa mass arising from the fourth ventricular wall causing obstructive hydrocephalus with elevated intracranial pressure. CSF analysis shows normal glucose and protein levels. Histopathology demonstrates perivascular pseudorosettes and true ependymal rosettes. Which tumor is most likely?
Answer choices
- AOligodendroglioma
- BEpendymomaCorrect answer
- CPilocytic astrocytoma
- DMedulloblastoma
- EMeningioma
- FChoroid plexus papilloma
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