Neoplastic cerebral aneurysm from metastatic lung adenocarcinoma associated with cerebral thrombosis and recurrent subarachnoid haemorrhage.

A 38 year old woman presented with a short history of headache, double vision, and rotatory vertigo. Medical history was negative except years of nicotine misuse. Cranial MRI disclosed a large infarction in the area supplied by the left posterior inferior cerebellar artery (PICA). Occlusion of the left vertebral artery was confirmed by MR angiography. Five months later, she was again admitted with headache, vomitus, and marked meningism. Cranial CT showed sub-arachnoid haemorrhage pronounced in the basal cisterns. Cerebral panangiography disclosed no vascular abnormality which could have explained the subarachnoid haemorrhage. Due to the angiography negative subarachnoid haemorrhage