Woven EndoBridge (WEB) device

The WEB device is a self-expanding braided mesh that sits entirely inside the aneurysm sac. Rather than filling the sac like coils, it disrupts blood flow at the neck, leading to thrombosis inside the aneurysm. It was designed for wide-neck bifurcation aneurysms, such as those at the basilar tip, middle cerebral artery bifurcation, internal carotid terminus and anterior communicating artery.

Because the device stays within the aneurysm, it usually does not require long-term antiplatelet therapy, an advantage over stent-based options. Device shapes include a barrel-shaped single-layer version (SL) and a spherical version (SLS), and sizing to the aneurysm's width and height is critical.

Occlusion after WEB treatment is assessed on follow-up angiography, often at around six months, using scales that distinguish complete occlusion, a neck remnant and an aneurysm remnant.