Basilar Artery Fenestration Aneurysm Treated With the Woven EndoBridge (WEB) Device: A Case Report and Review of the Literature.

Fenestration of the basilar artery (BA) is a rare congenital malformation resulting from anomalies in embryonic vascular development. Basilar artery fenestration aneurysms (BAFAs), especially in the proximal region, present unique challenges in neurosurgery. Their location in the critical and eloquent brainstem area makes open surgical clipping high-risk. Endovascular management has emerged as a less invasive alternative for aneurysms in such locations. The Woven EndoBridge (WEB) device (Terumo Neuro, Aliso Viejo, CA, United States) is a self-expanding, intrasaccular flow disruptor designed to treat wide-necked aneurysms without the need for additional devices, leading to improved outcomes and fewer complications from further interventions. This case describes a 52-year-old female patient with hypertension who presented to the emergency room following a two-minute seizure attack, preceded by a severe headache that began an hour earlier. Investigations revealed fenestration of the proximal BA trunk alongside a ruptured aneurysm at the fenestration set and diffuse subarachnoid hemorrhage (SAH). Successful embolization was performed using the WEB device, followed by flow diversion. BAFAs are rare vascular anomalies, and due to their critical location, careful assessment and treatment selection are crucial to avoid further complications. The WEB device offers a successful and viable treatment option, providing favorable outcomes with fewer complications.