Strategic Dual Approach for the Management of a Symptomatic Giant Partially Thrombosed Aneurysm at the Basilar Tip - Integrating Intrasaccular Flow Diversion and Endovascular Flow Reversal

Managing giant partially thrombosed intracranial aneurysms presents significant challenges due to their unfavorable natural history and the lack of standardized treatment approaches. Conventional treatments, whether open surgical or endovascular, often struggle to manage these aneurysms effectively, resulting in high recurrence rates or significant morbidity. The patient was a 62-year-old male with a symptomatic giant partially thrombosed aneurysm at the tip of the basilar artery, presenting with left-sided hemiparesis and dysarthria. Diagnostic imaging revealed a giant aneurysm with a wide-necked, canalized portion. A two-stage endovascular treatment was conducted, involving a balloon occlusion test and intraoperative monitoring for maximum patient safety. The treatment utilized stent-assisted Woven EndoBridge (WEB) embolization and serial bilateral vertebral artery trapping. The procedure successfully isolated the aneurysm and postoperative imaging confirmed the absence of recanalization, preserving the intact posterior circulation. The patient showed stable recovery and no neurological deficits during the 12-month follow-up period. This technical note demonstrates the feasibility and efficacy of strategically integrating intrasaccular flow diversion using a WEB device and flow reversal through bilateral vertebral artery trapping for treating giant partially thrombosed aneurysms.