This patient went on to have a biopsy which confirmed the diagnosis of a pineoblastoma. 

Pineoblastoma and germinoma are two main differential consideratins in the pediatric pineal region tumors. 

These tumors are both hypercellular lesions that share some imaging charachteristics (intermediate signal on T1 and T2 weighted images, CT hyperdensity and vivid contrast enhancement) as well as having a predilection of CSF dissemination. Germ cell tumors like germinoma engulf pineal gland calcification whereas pineoblastoma tend to disperse normal pineal calcification; thus the calcifications in these tumors are located peripherally.