Intracranial aneurysms in twins: case report and review of the literature.

Intracranial aneurysm in twins is a rare clinical disease entity. Only 15 cases have been described in the literature. We report on a pair of identical twins with intracranial aneurysms. One presented with subarachnoid haemorrhage; digital subtraction angiography showed a left posterior communicating artery aneurysm, which was treated by coiling. The patient's twin sister was called for screening, whereupon digital subtraction angiography revealed a right ophthalmic internal carotid artery aneurysm that was treated conservatively.