1374 Aneurysm Clipping on WEB Device: A Feasibility Study Using a Human Ex-Vivo Aneurysm Model

INTRODUCTION: The Woven EndoBridge (WEB) device is a breakthrough for brain aneurysm treatment. It's safe and effective for complex cases, but aneurysm filling or recurrence can still occur. A few cases of aneurysm clipping post-WEB use have been reported; however, the influence of clipping angulation and the ability of the clip to compress the WEB mesh is not well-defined. METHODS: The study utilized human placentas to create aneurysms via suture-closing of placental vessels. WEB devices were positioned in these aneurysms under fluoroscopic guidance, and various clip positions/angles on the WEB device were tested.DSA imaging acquisition and fluoroscopy monitored the effects of clipping on both the WEB device and aneurysm. Additionally, using a Kinevo 900 microscope (Carl Zeiss, Germany), we directly visualized the clipping process to enhance our understanding of the WEB’s mesh deformation. RESULTS: All clipping positions achieved complete aneurysm occlusion, collapsing the WEB mesh with no contrast flow observed into the aneurysm sac. Despite the WEB device's displacement within the sac, no significant morphological changes to the aneurysm were identified, and the presence of a neck remnant did not affect the adequacy of blade apposition. Notably, in direct visualization under the microscope and the placenta model, the blades of the clip were adequately opposed in all positions. CONCLUSIONS: Microsurgical clipping reliably collapses WEB devices, regardless of their placement or orientation. Our model suggests that clipping can effectively address in-vivo recurrences and persistent aneurysm filling of aneurysms treated with the WEB device. Our model does not assess the influence of WEB healing within the aneurysm.