MRI
Posterior fossa mass that primarily lies in the midline of the superior cerebellum, separate from the fourth ventricle. It has heterogeneous T1 and T2 signal, and on post contrast imaging there is heterogeneous enhancement with central low signal. There is a broad dural attachment to the inferior surface of the left tentorium cerebelli, where it extends around the anterior edge and lines the superior surface.
Few foci of blooming artifact, which is likely blood product. Peripheral diffusion restriction. Surrounding in FLAIR signal in the cerebellum, tectal plate and medial left occipital lobe most in keeping with vasogenic oedema. There is partial effacement of the fourth ventricle and complete effacement of the inferior cerebral aqueduct with resultant obstructive hydrocephalus.