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Published on: October 11, 2024
Smaller WEB devices show lower retreatment rates than larger devices: results from the WorldWideWEB study
Franja Dugar1, Hamza Adel Salim2,3, Basel Musmar4
1Department of Radiology, Neuroradiology and Nuclear Medicine, Stadtspital Zurich, Zurich, Switzerland.
Objectives:
Small Woven EndoBridge (WEB) devices (≤ 4.5 mm) for the intracranial aneurysm treatment are technically challenging to deploy, with limited efficacy and safety data. This study compared functional, angiographic, and safety outcomes of small WEBs with large (> 4.5 mm) and very large (> 7.5 mm) WEBs.
Materials And Methods:
The WorldWideWEB consortium is a retrospective, multicenter collaboration across 30 international institutions including adults with intracranial aneurysms treated with WEB. Patients were stratified into small (≤ 4.5 mm) and large (> 4.5 mm) groups; a subanalysis compared small with very large (> 7.5 mm) devices. Primary outcome was retreatment rate. Secondary outcomes included modified Rankin Scale (mRS), angiographic outcomes periprocedurally and last follow-up (FU), and safety events (intracranial hemorrhage (ICH) and thromboembolic complications (TECs)).
Results:
Among 1473 patients, 229 (15.5%) received small WEBs. Baseline characteristics were similar. Small WEBs showed lower retreatment (4.3% vs 8.8%, p = 0.04) and higher complete occlusion (periprocedurally: 57.1% vs 36.6%, p < 0.01; FU: 76.2% vs 58.5%, p < 0.01). Median mRS was comparable (1 [1-2] vs 1 [1-2], p = 0.88), as was safety (ICH 2.6% vs 0.9%, p = 0.10; TECs 3.1% vs 3.9%, p = 0.69). Very large WEBs had higher retreatment (16.1%, p < 0.001) and lower complete occlusion (periprocedurally: 32.2%, p < 0.001; FU: 50.5%, p < 0.001), with comparable safety (ICH 0.9%, p = 0.27; TECs 4.5%, p = 0.51).
Conclusion:
Small WEBs demonstrated lower retreatment, superior anatomic and comparable clinical outcomes compared with large devices, with similar safety profiles.
Key Points:
Question Do small Woven EndoBridge devices have comparable efficacy and safety to larger devices for intracranial aneurysm treatment despite technical deployment challenges? Findings Small Woven EndoBridge devices (≤ 4.5 mm) achieved lower retreatment rates and superior angiographic occlusion compared with larger devices, with similar safety and functional outcomes. Clinical relevance These findings support the use of small Woven EndoBridge devices for appropriately sized aneurysms, providing reassurance that deployment challenges do not translate into worse clinical outcomes, while superior anatomic outcomes may encourage their broader adoption in clinical practice.
