Dissecting vertebral aneurysm. Report of a case

Abstract

Aneurysms of the vertebral artery (VA) are relatively uncommon, accounting for less than 0.5-3.0% of all aneurysms and 20% of aneurysms originating in the posterior fossa. There are three distinct forms of aneurysms: saccular, fusiform and dissecting. The diagnosis of dissecting aneurysm is based on the findings of angiography, surgery and autopsy. Irregular fusiform appearance, intramural retention of contrast medium in the venous phase and alternating irregular stenotic and dilated segment (string and pearl sign) are the basal angiographic findings. Patients with dissection of VA often develop subarachnoid hemorrhages (SAHs), with the typical neck pain or suffer cerebral ischemia. Because of the high risk of rebleeding of dissecting aneurysms, they should be treated as soon as possible, with occlusion of the VA. Nowadays, both surgical and endovascular procedures allow the treatment of dissecting vertebral aneurysms. Anyway, one should be aware that vertebral occlusion performed proximal to PICA origin may be followed by ischemic complications. In this paper, we discuss the diagnostic and therapeutic difficulties associated with dissecting vertebral aneurysms on the basis of personal observation and a review of the literature.