Pre and Post

The arrow points to a sporadic congenital developmental lesion whose pathogenesis is not well understood. Patients usually present between ages 10 to 40. Children are more likely to present with intraparenchymal or subarachnoid hemorrhage whereas adults can present either with a bleed or a seizure.

This angoigram shows the lesion after treatment.

Challenge: What are we looking at?

Both images shown under Fair Use.