Propensity Score-matched Comparison of WEB17 and WEB21 with 4-7 mm Device Sizes for the Treatment of Unruptured Intracranial Aneurysms.

Abstract

The WEB17 system represents the fifth generation of Woven Endobridge (WEB) flow disruptors and features alow profile with fewer wires than its predecessor, the WEB21. The present study compares the safety and efficacy of the WEB17 and WEB21 for the treatment of unruptured cerebral aneurysms with 4-7 mm device sizes, which were available for both systems. Patient and aneurysm characteristics, complications, clinical outcome and angiographic results were retrospectively analysed. 1:1 propensity score matching was performed to adjust for minor baseline differences between the groups. Sixty aneurysms treated with WEB21 and 90with WEB17 were included. The overall failure rate (deployment failure and adjunctive stent) was significantly higher with WEB21 (16.7%) than with WEB17 (3.3%, p < 0.01). The rates of neurological events between WEB21 (6.7%) and WEB 17treatment (1.1%) were not significantly different (p = 0.08). Also, procedural morbidity was comparably low in both groups (WEB21: 3.3%, WEB17: 0%, p = 0.16). The rates of complete/adequate occlusion at follow up were 69.7%/86.4% for WEB17 vs. 80.4%/91.3% for WEB21 at short-term (p = 0.27), and 64.5%/83.9% vs. 75.9%/86.2% at mid-term (p = 0.41), respectively. Propensity score matching confirmed the results of the unmatched series. WEB17 and WEB21 hadasimilar safety and efficacy profile, but WEB17 was associated with an improved feasibility. Prospective studies with long-term follow-up will define the full potential of the WEB17 system.