Far Lateral Approach and Occipital Artery to Posterior Inferior Cerebellar Artery Bypass With Staged Flow Diversion for Treatment of De Novo Vertebrobasilar Junction Aneurysm: 2-Dimensional Operative Video

Intracranial aneurysms refractory to endovascular treatment often require complex cerebral revascularization strategies, including combined open-endovascular techniques.1-3 An adolescent girl presented with headache, and a fusiform right V4 vertebral artery aneurysm was diagnosed. Initial treatment was attempted with coil embolization. Surveillance imaging at 3 years after embolization demonstrated a de novo vertebrobasilar junction (VBJ) aneurysm with involvement of the right anterior inferior cerebellar artery-posterior inferior cerebellar artery (PICA) origin. The VBJ aneurysm was initially observed. Enlargement was noted at 1 year, and secondary treatment was attempted with left V3 segment coil occlusion to induce flow reversal. Follow-up demonstrated progressive VBJ aneurysm enlargement, prompting attempted left occipital artery (OA)-PICA bypass at an outside facility, which was unsuccessful. The patient was referred to our institution. After her parents gave informed consent, she underwent right OA-PICA bypass on the contralateral side through far lateral craniotomy with inside-out harvest of the donor vessel.4 After trapping and arteriotomy of the recipient PICA, an OA-PICA end-to-side anastomosis was performed using a running continuous technique.5 Intraoperative indocyanine green videoangiography and postoperative digital subtraction angiography confirmed patency of the bypass. The patient tolerated the procedure well and remained neurologically intact. On postoperative day 3, a staged transcirculation flow diversion device was placed to facilitate progressive thrombosis of the aneurysm.6,7 Follow-up angiography at 1 year demonstrated complete occlusion of the aneurysm. This video demonstrates successful multimodal management of a complex de novo VBJ aneurysm after a series of refractory endovascular treatments and unsuccessful cerebral revascularization techniques.