MRI obtained a number of weeks earlier (before the VP shunt as inserted) demonstrates a large pineal region mass with intermediate signal intensity is seen in T2W images. Hydrocephalus and periventricular CSF flow (interestitial edema) are also visible.
Post contrast T1W images shows mildly heterogenous but vivid enhancement and invasion to the quadrigeminal plate, third ventricle and superior cerebellum.
Two regions of ependymal enhancement are seen in frontal horns of lateral ventricles as well as filling of the infundibular and supraoptic recesses of the third ventricles. Leptomeningeal enhancement is also prominent elsewhere. These are in keeping with ependymal dissemination.