Vertebral Artery-to-Middle Cerebral Artery Bypass with Coil Embolization of Giant Internal Carotid Artery Aneurysm: Technical Case Report

Abstract

Cerebral revascularization with extracranial-to-intracranial bypass is often required during the surgical treatment of complex intracranial aneurysms. This report is the first in which a vertebral artery (VA)-to-middle cerebral artery (MCA) bypass in conjunction with endovascular coil embolization is used in the successful treatment of a giant intracranial aneurysm. A 68-year-old man previously diagnosed with a 6-cm internal carotid artery (ICA) aneurysm presented complaining of progressing left hemiparesis and mental status changes. His aneurysm had been treated previously by common carotid artery occlusion 20 years earlier. Arteriography defined the partially thrombosed, right supraclinoid ICA aneurysm arising at the junction of the posterior communicating artery and the supraclinoid ICA. Because of the patient's worsening symptomatology, endovascular coiling with placement of a superficial temporal artery-to-MCA bypass was performed. The patient tolerated this procedure well, and his symptoms resolved. However, they recurred several months later, and imaging suggested poor right hemispheric perfusion despite a patent bypass. A VA-MCA bypass using a saphenous vein graft was then performed using the distal right VA at the level of cervical vertebra 1 (C1) as the donor vessel with a distal anastomotic site on the right MCA. Coil embolization of the aneurysm was repeated, and the feeding posterior communicating artery was sacrificed. The patient is currently asymptomatic more than 1 year after the second bypass and coil embolization. This report describes a safe and definitive treatment option for a giant intracranial ICA aneurysm using a posterior-to-anterior circulation (VA-MCA) bypass, followed by endovascular coil embolization in a patient with previous ligation of the common carotid artery. VA-MCA high-flow saphenous vein bypass followed by coil embolization is a useful technique that is especially valuable in the subset of giant aneurysm patients who have previously been treated by carotid ligation.