Posterior fossa gangliocytoma with facial nerve invasion: case report.

A 5 year-old boy with a cerebellar gangliocytoma with a peripheral right facial paresis and ataxia is presented. His MRI showed a heterogenous, diffuse lesion, isointense on T1 and hyperintense on T2-weigthed sequences, involving the right cerebellar hemisphere with direct extension into the right facial nerve. The present case is the first description of a gangliocytoma with direct facial nerve invasion, as demonstrated for the facial nerve paresis and supported by MRI and surgical inspection.