Abstract Number: Esoc2026a1925 Endovascular Vertebrobasilar Sacrifice Using the Lobo Occluder for Complex Fusiform Aneurysm Treatment

Background and aims Fusiform aneurysms of the vertebrobasilar circulation present significant therapeutic challenges due to circumferential dilation without discrete necks and involvement of critical perforating vessels. These lesions demonstrate unfavorable natural history with higher annual growth (12% vs 3%) and rupture rates compared to dolichoectatic aneurysms. The LOBO® device (Okami Medical) is a low-profile braided occluder originally developed for peripheral embolization that offers potential advantages including self-expansion, minimal porosity for immediate flow disruption, and navigation through tortuous anatomy. Methods We present a technical case report of a 61-year-old male with progressive vertigo, occipital headaches, and sixth nerve palsy. Imaging revealed a 9.5 mm fusiform basilar artery aneurysm at the vertebrobasilar junction demonstrating interval growth. A hybrid endovascular strategy was employed via bilateral radial access: flow diversion using three telescoping Pipeline devices through the dominant right vertebral artery, combined with left vertebral artery sacrifice using a 5 mm LOBO® device positioned distal to the PICA origin. Results Technical success was achieved with complete left vertebral artery occlusion, preserved retrograde PICA perfusion, and flow stasis within the aneurysmal sac. No procedural complications occurred. At 2-week follow-up, headaches and gait ataxia resolved. Three-month MRA demonstrated approximately 40% aneurysmal volume reduction with stable occlusion. At 4-month follow-up, the patient was asymptomatic with modified Rankin Scale score of 0. Conclusions This case represents one of the first reported intracranial applications of the LOBO® device for parent vessel sacrifice in complex vertebrobasilar aneurysm management, demonstrating promising technical performance and clinical outcomes.