[Intracranial dissecting aneurysms of the posterior circulation: report of 3 cases and review of the literature].

Dissecting aneurysms of cerebral arteries are unusual causes of stroke. The carotid system is the commonest site of this pathology, the vertebral arteries are less involved and dissection of the basilar artery is rare. The authors report three cases of arterial dissection of the vertebrobasilar system, two of the vertebral arteries and one of the basilar artery. An extensive review of the literature is presented. The clinical picture of dissection of vertebrobasilar system was inespecific but pain was a prominent symptom, though had not occurred in the site of the arteries involved. The pain was suggestive of subarachnoid hemorrhage. Associated or risk factors were mild trauma, migraine and high blood pressure. The angiographic findings were suggestive, however just the "double lumen" has been considered pathognomonic. The prognosis is variable. It was benign in case 3, left sequela in case 2, and case 1 rebleed fatally.