Endovascular treatment for vertebral dissecting aneurysm presenting with subarachnoid hemorrhage.

We report results and problems of the endovascular treatment in 12 cases of intradural vertebral dissecting aneurysm presenting with subarachnoid hemorrhage. There were four complications related to interventional procedure and conventional angiography. In three patients (25%), VDAs ruptured immediately after injection of contrast media or hypertension during the interventional procedure, which caused respiratory arrest. In a case of bilateral VA dissection (8%), after proximal VA occlusion had been performed for unilateral VDA, contralateral dissection extended to the basilar artery resulting in brain stem infarct. We suggest that the incidence of rebleeding of VDA during angiography and embolization is higher than that of usual saccular aneurysms. Careful injection of contrast media and strict blood pressure control seems to be more important to prevent rebleeding in VDAs than intracranial saccular aneurysms. Since unilateral VA occlusion may extend contralateral dissection in a case of bilateral VA dissection, it is necessary to check contralateral VA dissection before VA occlusion.