無症候性非血栓化椎骨動脈紡錘状脳動脈瘤の自然経過

―10例の検討―

抄録

The natural history of incidentally found non-thrombosed fusiform aneurysms of the vertebral artery has not yet been determined. We retrospectively analyzed 10 asymptomatic cases confirmed by head MRI and cerebral angiography. All were males aged from 42 to 73 years old (mean±SD 56.3±9.90). Three cases were found in a brain doc, another 3 were incidentally found in the workup of other neurological disease, and 4 were found in screening for chronically sustained headache. The patients’ vascular risk included hypertension, hyperlipidemia and smoking.
The aneurysms were found more often on the right (8 out of 10). The aneurysmal wall contained major cortical arteries in all cases except 1 who received endovascular trapping. The endoview mode obtained from 3D-DSA revealed smooth arterial surface seen from the inside. The treatment option was vascular risk control in most cases, with the exception of 2 endovascular procedures according to the patients’ will. Compared with the symptomatic cases, the characteristics of the asymptomatic cases resembled those of cases with cerebral infarction such as age, sex and natural history. It may be that the asymptomatic cases represent the chronic phase of unnoticed dissection of the vertebral artery. The endosurface view obtained from 3D-DSA might reflect the change they had taken.
Although based on only a limited number of cases, this study indicates the possibility of a benign natural history of asymptomatic non-thrombosed fusiform aneurysm of the vertebral artery.