A large (5.3 x 3.6 x 3.7 cm) well-defined midline-centred mass is identified posterosuperior to cerebellum, producing apparent splitting of the falx cerebelli. It has a sharp lobulated outline, containing multiple loculi of mixed hyper & hypodense appearance. The mass compresses upon cerebellar vermis & both hemispheres as well as fourth ventricle. Rest of the ventricles and extraventricular CSF spaces appear widened.