A large mixed-signal intensity solid hyperintense mass, and heterogeneous contrast enhancement is noted epicentre in the 4th ventricle resulting in obstruction with supratentorial ventricular dilatation and periventricular lucencies in keeping with transependymal CSF leak due to acute obstruction. ADC maps demonstrate intermediate values, facilitated compared to the adjacent cerebellum. The mass is diffusion restricted with minimal perilesional oedema. The rest of the brain parenchyma appears normal.