Saphenous vein graft reconstruction of an unclippable giant basilar artery aneurysm performed with the patient under deep hypothermic circulatory arrest: Technical case report

OBJECTIVE AND IMPORTANCE: Effective treatment for unclippable giant vertebrobasilar aneurysms remains unclear. We present the first reported case of a giant vertebrobasilar aneurysm being successfully treated with trapping of the aneurysm and internal carotid artery to basilar artery bypass with a saphenous vein graft that was performed with the patient under hypothermic circulatory arrest. CLINICAL PRESENTATION: A 15-year-old female patient with a history of probable subarachnoid hemorrhage and chronic headaches presented with a relatively acute exacerbation of her headache, nausea, vomiting, and weakness. Imaging studies revealed a 4 x 4 x 3-cm vertebrobasilar aneurysm, supplied by an angiographically dominant right vertebral artery and causing significant brain stem compression. INTERVENTION: Initially, a petrosal approach with a hearing-preserving partial labyrinthectomy was used to perform a right external carotid artery to posterior cerebral artery bypass with saphenous vein. Delayed occlusion of the right vertebral artery with an intraluminal balloon was planned; however, intraoperative angiography revealed poor graft flow, presumably because of the small size of the posterior cerebral artery. Postoperative graft occlusion was anticipated. During this same time interval, the patient deteriorated neurologically. Brain imaging failed to reveal evidence of cerebral infarction. The patient underwent subsequent surgery. After a total petrosectomy, the aneurysm was trapped, an aneurysmectomy was performed, and, with the patient under deep hypothermic circulatory arrest, a new interposition saphenous vein graft was inserted between the internal carotid and basilar arteries. Excellent flow was observed angiographically. At her 4-month follow-up examination, the patient had improved to near baseline. CONCLUSION: We present a technically challenging but safe and definitive treatment option for an unclippable giant vertebrobasilar aneurysm. Using cranial base approaches and hypothermic circulatory arrest techniques, aneurysmal trapping and successful bypass grafting directly into the basilar artery was performed.