Large intraventricular haemorrhage evident with blood evident in all ventricles, greatest in the right lateral ventricle and third ventricles. There is associated marked hydrocephalus and signs of raised intracranial pressure with effacement of the cortical sulci and basal cisterns. There are probable small amounts of subarachnoid blood evident.
Abnormality is seen in relation to the A1 segments of the anterior cerebral arteries, M1 segments of the middle cerebral arteries and distal internal carotid arteries. These vessels are of narrow calibre and there is irregular luminal enhancement, particularly involving the A1 segments bilaterally. There are mildly prominent collateral vessels. A definite focal aneurysm is not identified. The differential diagnosis for this appearance includes vasospasm, secondary to the large amount of haemorrhage. Other causes would include an obstructive vasculopathy (moya-moya) and vasculitis. Whilst not identified on this study, an aneurysm is not excluded.