Failure of stent-assisted endovascular treatment for ruptured dissecting aneurysms of the basilar artery.

We report two instructive cases of ruptured dissecting aneurysm of the basilar artery. Although stent-assisted endovascular treatment was successful, recurrent bleeding occurred 4 h after the procedure in one patient, and the other's basilar artery occluded 6 days after the procedure. These cases suggest that the high porosity of currently available stents may be insufficient to induce intraluminal thrombosis and merely stenting may fail to prevent bleeding, while postoperative anticoagulation alone may be inadequate to prevent occlusion of the stented vessel.