A large (6.5 x 5.6 x 6.3 cm) extra axial, abnormal signal intensity mass lesion in the left cerebello-puntine angle extending to the foramine magnum inferiorly and to the level of tentorium cerebelli superiorly.
The lesion returns high signal intensity on T2WI, low signal on T1WI and heterogeneous signal on FLAIR images.
Diffusion restriction is noted in the mass lesion.
No dropout signal in T2* GRE images to suggest intra lesional hemorrhage/calcification.
No post contrast enhancement of the lesion or adjacent meninges.
No adjacent inflammatory or infiltrative changes.
This abnormal mass lesion is resulting in compression over the adjacent left cerebellar hemisphere, brain stem and sylvian aqueduct resulting in obstructive moderate hydrocephalus.