Neurodegenerative Diseases USMLE Step 1 Practice Question
A 4 year old girl has focal seizures and developmental delay. Examination shows a dark red vascular lesion over the forehead and upper eyelid in the distribution of the ophthalmic branch of the trigeminal nerve. CT of the head shows gyriform intracranial calcifications. Which embryologic abnormality most likely underlies this condition?
Answer choices
- ASomatic mutation causing cerebellar hemangioblastomas
- BPersistence of vascular malformations involving leptomeninges and faceCorrect answer
- CX linked mutation causing peroxisomal dysfunction
- DLoss of heterozygosity at the NF2 locus
- EFailure of neural crest migration causing absent enteric ganglia
- FAutosomal dominant VHL mutation causing hypervascular malformations
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