There is a sharply defined, cystic, intra-axial mass lesion within the right cerebellar hemisphere. There is a mixed intensity (solid and cystic spaces within) and avidly enhancing eccentric mural nodule present. The wall of the lesion remains non-enhancing. There is no associated restriction on diffusion imaging. There are eccentric peripheral flow voids best identified on T1 imaging. There is perilesional oedema, focal mass effect with attenuated basal cisterns and brain stem. There is cerebellar tonsillar herniation at 13mm. There is tri-ventricular obstructive hydrocephalus with periventricular trans ependymal oedema. There is prominent perioptic CSF and raised intracranial pressure likely accounting for papilloedema. Multiparametric MRI brain and cervical spine are otherwise unremarkable.