Sometimes the Aunt Minnies of pathology is arduous to unveil when they change in appearance after complication.
Being meticulous about the content of the lesion is invaluable to narrow the diagnosis, as in this case of cavernoma which could be misinterpreted as cortical based cystic mass with non-enhancing nodule.
Cavernoma is an intracranial vascular malformation with repeated intralesional hemorrhages into thin walled angiogenically immature blood filled locules called caverns.These are well marginated lesion that do not contain normal brain parenchymas and is surrounded by hemosiderin rim. They occur anywhere in the CNS and appears as non-enhancing discrete reticular or ‘popcorn ball’ lesion with mixed signal core surrounded by complete hemosiderin rim on T2WI that boom on T2*.
Ganglioglioma: cortical based cyst with non-enhancing mural nodule but no gross hemorrhage or frank necrosis.
Pilocytic astrocytoma: supratentorial and hemorrhage uncommon, cystic with strong enhancing mural nodule and calcification, among children in the posterior fossa (60%).
Pleomorphic xanthoastrocytoma: supratentorial well delineated peripheral cortically based mass in children and young adults with cyst and enhancing nodule and calcification (40%). Despite its fat content they appear hypointense on T1. Hemorrhage is rare.
Oligodendroglioma: rare in children (1-5%), slow growing peripheral cortically based non-enhancing nodule with calcification and cystic degeneration. Gross hemorrhage and peritumoral edema less common if present indicate malignant degeneration.