Introduction: Our goal is to evaluate the role of bypass surgery in patients with congenital fusiform intracranial internal carotid artery (ICA) aneurysms. These are rare, morbid and direct surgical treatment is challenging 1. They are not amenable to endovascular coiling or microsurgical clipping, making bypass surgery a favorable treatment option. No clear guidelines exist regarding when bypass surgery is more appropriate than stenting.
Methods: A retrospective analysis of our database identifying all patients with symptomatic fusiform congenital intracranial ICA aneurysms who underwent surgical treatment from August 2000 to November 2016. Fifteen patients; all status-post EC-IC bypass, with or without ICA ligation.
Conclusions: Our series illustrates that EC-IC bypass surgery, combined with proximal carotid occlusion, in patients with fusiform ICA aneurysms can be done safely with minimal long-term graft-related complications. BTO tolerance was used to guide decision and timing of ICA ligation in several cases. In order to avoid perioperative ischemic events from poor collateral circulation in patients without BTO tolerance, intracranial arterial flow patterns can be analyzed using NOVA MRI techniques. Endovascular treatment with flow-diverting stents, though an appealing less-invasive alternative, also has its limitations, including higher recurrence rate (especially with large or giant aneurysms), association with perforator infarcts, increased morbidity and mortality when used with an acute subarachnoid hemorrhage, and dual-antiplatelet regimen postoperatively. Ultimately, individual patient characteristics and risk factors must be carefully weighed when deciding on a treatment strategy. Patients medically able to tolerate EC-IC bypass surgery and proximal carotid occlusion should be evaluated for this treatment strategy preferentially.
Patient Care: Our study helps shed light on one of the two major treatment options for these rare but morbid aneurysms. Many papers describe successful endovascular treatments in the current stent/flow-diverter era. Our study illustrates that bypass surgery can be done safely and with overall good outcomes and should be considered when discussing treatment of these aneurysms.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the role of balloon test occlusion in bypass surgery decision-making, 2) Discuss, in small groups, the risks and benefits of surgical revascularization versus endovascular treatments, 3) Identify the indications for bypass surgery and the different possible treatment steps
References: 1. Kai Y, Hamada J, Morioka M, et al. Treatment strategy for giant aneurysms in the cavernous portion of the internal carotid artery. Surg Neurol. 2007;67(2):148-155; discussion 155.
2. Zhu W, Tian Y-L, Zhou L-F, Song D-L, Xu B, Mao Y. Treatment Strategies for Complex Internal Carotid Artery (ICA) Aneurysms: Direct ICA Sacrifice or Combined with Extracranial-to-Intracranial Bypass. World Neurosurg. 2011;75(3-4):476-484.
3. Gross BA, Moon K, Ducruet AF, Albuquerque FC. A rare but morbid neurosurgical target: petrous aneurysms and their endovascular management in the stent/flow diverter era. J NeuroInterventional Surg. 2017;9(4):381-383.
4. Kalani MYS, Ramey W, Albuquerque FC, McDougall CG, Nakaji P, Zabramski J, Spetzler RF. Revascularization and Aneurysm Surgery: Techniques, Indications, and Outcomes in the Endovascular Era. Neurosurgery. 2014;74:482-498.
5. Kalani MYS, Elhadi AM, Ramey W, et al. Revascularization and Pediatric Aneurysm Surgery. J Neurosurg Pediatrics. 2014;13:641-646.
6. Field M, Jungreis CA, Chengelis N, et al. Symptomatic Cavernous Sinus Aneurysms: Management and Outcome After Carotid Occlusion and Selective Cerebral Revascularization. AJNR. 2003;24:1200-1207.
7. Chen C, Hou B, Li WS, Guo Y. Combining Internal Carotid Ligation with Low-Flow Bypass for Treating Large-Giant Cavernous Sinus Segment Aneurysms: A Report of Four Cases. World Neurosurgery. 2017;100:280-287.