Fig. 6

Radiological findings demonstrating response to chemotherapy. Case #4 shown. A A small foci of calcification is depicted on CT scan and susceptibility-weighted imaging MRI (short white arrow). Supratentorial obstructive hydrocephalus and macrocrania are also observed. A, B Heterogeneous tectal and pineal region solid cystic mass, with intense heterogeneous enhancement and rapid overgrowth within two months. B The solid component is highly cellular with marked restriction on ADC map (white star). A rim of increased blood flow on ASL perfusion map is observed in the periphery of the mass (long white arrows), possibly related to neovascularization. Leptomeningeal enhancement is also observed (open black arrow). C Significant shrinkage of the tectal and pineal region mass after chemotherapy was observed, with nearly complete resolution of the intracranial leptomeningeal enhancement