There is a 2.9 x 1.9 x 2.4 cm mass within the right inferior fourth ventricle extending through the right foramina of Luschka with distortion of the right medulla and partial effacement of the ventricle.
It is predominantly solid with a few small cystic foci at its periphery.
The solid component is hyperintense to brain parenchyma on T2 weighted sequence, isointense on T1, and enhances vividly.
There are multiple vascular flow voids. No abnormal diffusion restriction within the lesion. Multiple foci of coarse calcification on recent non-contrast CT scan is noted.
Inferiorly, the mass abuts the right PICA at its origin. T2 flow-void in the right vertebral artery is preserved.
There is mass effect and partial effacement of the inferior aspect of the fourth ventricle. No upstream ventricular dilation or evidence of transependymal CSF shift.No other abnormal enhancement is demonstrated.
Enhancing mass with peripheral cystic foci within fourth ventricle and extending through foramina of Luschka, without obstructive hydrocephalus.
Haemangioblastoma would be the most common adult solid/cystic posterior fossa tumour with flow voids, but classically should not contain calcification.
Medulloblastoma, choroid plexus papilloma and infratentorial ependymoma are possibilities although rare in adults.