Coil Embolization and Basilar Artery Occlusion to Treat a Partially Thrombosed Aneurysm at the Basilar Artery Bifurcation

Partially thrombosed basilar artery bifurcation aneurysms that are not amenable to clip application are among the most challenging lesions. We report a case with a partially thrombosed basilar artery bifurcation aneurysm successfully treated by parent artery occlusion combined with endovascular embolization. The patient, who had undergone neck clipping 12 years before, presented with conscious disturbance, tetraparesis, dysphagia, dyarthria, and diplopia. Neuroimaging examinations such as CT scan, MRI and angiography revealed that a partially thrombosed basilar artery aneurysm compressed the brain stem severely. We performed rough packing of the aneurysm by GDC. After coil embolization, we surgically obliterated the basilar artery at the proximal portion of superior cerebellar artery. An MRI study demonstrated reduction of the mass volume of aneurysm and an angiography study did not show regrowth of the aneurysm over a 5-year follow-up period. The patient's neurological deficits caused by the compression of the brain stem disappeared. We consider that basilar artery occlusion combined with coil embolization is a valid procedure for partially thrombosed basilar artery aneurysms.