Simultaneous presentation of two cerebral arterial aneurysms.

A case of subarachnoid haemorrhage due to rupture of a middle cerebral artery aneurysm followed by immediate enlargement of a carotid intra-cavernous aneurysm is described. The enlargement of the second aneurysm was due to a rise in blood pressure caused by the subarachnoid haemorrhage. Although multiple aneurysms are common, this phenomenon is very rare and the reasons for this are discussed.