Dissecting aneurysm of the petrous portion of the internal carotid artery. Case report and review of previous cases.

A "spontaneous" dissecting aneurysm of the petrous portion of the right internal cartoid artery in a 60 year old man was demonstrated angiographically. It showed a typical double lumen which is rarely demonstrated by angiography. It was probably of atherosclerotic origin. In addition, a survey of the positions and angiographic characteristics of the 29 traumatic and "spontaneous" dissecting aneurysms of the common and internal carotid arteries found in the literature is presented.