Presentation
Occipital headache and vomiting
Patient Data
There is a 4.3 cm predominantly solid space-occupying lesion filling and expanding the fourth ventricle. It displays diffusion restriction and is of intermediate signal on T2 imaging. The tumor is expanding the right foramen of Luschka and peripherally displacing the pons and cerebellar vermis effacing CSF from the foramen magnum and pre pontine cistern. There is striking hydrocephalus with marked dilatation of the third and lateral ventricles with extensive transependymal edema and partial effacement of the sulci. There is CSF distension of the optic nerve sheaths.
There is a small nodule of the same signal intensity involving the suprasellar cistern representing a metastatic deposit.
Case Discussion
A pathologically proven metastatic medulloblastoma.