MRI
Cerebellar midline patchily enhancing mass that is T2/FLAIR high signal centered on the vermis extending into the cerebellar hemispheres, more so on the right. No abnormally restricted diffusion or blooming artifact.
Superiorly, high FLAIR signal extends through the left superior cerebellar peduncle into the left periaqueductal grey matter and tectal plate with narrowing of the cerebral aqueduct. Inferiorly, high FLAIR signal extends into the left cerebellar tonsil.
Mass effect on the fourth ventricle, which is nearly effaced. Mild ventriculomegaly. Scattered high FLAIR signal foci in the centrum semiovale.