Surgical material is noted in the region of the cisternal left trigeminal nerve. Wedge-shaped region of hypoattenuation involving the superior and lateral aspect of the left cerebellar hemisphere does not conform to an arterial vascular territory, in keeping with a venous infarct. Anteriorly there is a small amount of hyperdense blood which is likely subarachnoid. There is mild mass-effect within the posterior cranial fossa, with displacement of the fourth ventricle to the right. No supratentorial midline shift or hydrocephalus. No hypodensity within the left sigmoid and transverse sinus.