There is a large T2 hyperintense avidly enhancing heterogeneous mass centred within and splaying the fourth ventricle extending downward through the bilateral foramina of Luschka, foramen of Magendie, into the cisterna magna and approximately 1.7 cm below the foramen magnum. The mass exerts mass effect compressing the brainstem most notably at the level of the pons and medulla with mass effect on the proximal cervical spinal cord at C2. The mass also causes superior vermian deviation. Mild punctate calcifications and/or microhemorrhages are within the tumor along with minimal foci of tumoral increased DWI signal.
There is moderate obstructive hydrocephalus with periventricular edema.
No visible associated leptomeningeal metastasis.