Woven EndoBridge Shape Modification
After Intracranial aneurysm embolization with the Woven EndoBridge (WEB) device, worsening of aneurysm occlusion or re-opening was reported to be possibly associated with WEB shape modification, it is a frequently observed phenomenon.
Woven EndoBridge Shape Modification can be partly overcome by use of an appropriate width oversizing strategy that could lead to improved angiographic results 1)
Woven EndoBridge shape modification was strongly influenced by the aneurysm shape and ostium size, and it was not independently associated with the angiographic occlusion 2)
Nawka ete al. from University Medical Center Hamburg tested the hypothesis that WSM is associated with worse aneurysm occlusion on short-term angiographic follow-up images.
Patients with short-term follow-up digital subtraction angiography (DSA) available were included. Baseline patient characteristics, aneurysm morphometrics, and WEB dimensions (“conventional” parameters) and height and width WSM (“WSM” parameters) in the initial and the follow-up examination were analyzed. For ordinal regression analyses, aneurysm occlusion was graded according to the Bicêtre Occlusion Scale Score (BOSS; grades 0, 0', 1, 2, 3, and 1 + 3). Receiver operating characteristic curve analysis was used to distinguish adequately (BOSS 0, 0', and 1) from incompletely (BOSS 2, 3, and 1 + 3) occluded aneurysms.
They included 93 patients with 96 aneurysms. Adequate occlusion was observed in 72 cases (75.0%). In univariate ordinal regression analysis, width WSM in anteroposterior DSA (odds ratio = 0.96, 95% CI: 0.94-0.99, P = .010) and in lateral DSA (odds ratio = 0.98, 95% CI: 0.97-0.99, P = .049) were significantly associated with the BOSS after 6 months. In multivariate regression analysis, WSM was not independently associated with aneurysm occlusion. Based on receiver operating characteristic curve analysis, the area under the curve (AUC) of the “conventional” model (AUC = 0.83, 95% CI 0.74-0.90) was higher than the AUC of the “WSM” model (WSM; AUC = 0.70, 95% CI 0.60-0.79).
WSM was not independently associated with angiographic aneurysm occlusion status after 6 months. However, the “conventional” parameters including sex, rupture state, WEB type, WEB width, aneurysm width, height, and volume were associated with partial aneurysm recanalization in WEB-treated patients at the short-term follow-up 3).
Thirty patients with 32 WEB-treated intracranial aneurysms fulfilled the inclusion criteria of cranial CT at baseline (day of intervention) and a follow-up CT at least >1 months' later (median follow-up time, 11.4 months; interquartile range, 6.5-21.5 months). Adequate occlusion was observed in 84.4%, and aneurysm remnant, in 15.6%. WEB shape modification was quantified by a semiautomated approach on CT scans. Time courses were evaluated graphically and analytically; association analyses were performed by linear mixed-effects regression models.
In 29/32 WEB devices (90.6%), the reduction in height was found to be at least 5%. The decrease in height with time was significantly associated with the time interval in days since the intervention (P < .0001): A stronger decrease in WEB height was associated with a longer time since the intervention (median reduction in 1 year, 19.2%; range, 8.6%-52.3%). No significant association was found with the quality of aneurysm occlusion, device size, rupture status of the aneurysm, aneurysm location, and reintervention rate.
Shape modification was common in WEB-treated intracranial aneurysms with a median height reduction of 19.2% in 1 year. The quality of aneurysm occlusion was not associated with WEB modification 4).
All patients with aneurysms treated with the WEB were prospectively included in a data base. Demographics, aneurysm characteristics, adverse events, and anatomic results were retrospectively analyzed. Anatomic results and modification of the WEB shape on the follow-up examinations were independently evaluated by a core laboratory.
Results: Thirty-nine patients were included. We observed few complications: intraoperative rupture in no patients (0.0%) and thromboembolic events in 3 patients (7.7%) with a permanent deficit in 1 (2.6%). At short-term, midterm, and long-term follow-up, adequate occlusion was obtained in 86.8%, 83.3%, and 87.5%, respectively. Retreatment rates were low (5.1%). At 6 months, WEB shape modification (compression/retraction) was observed in 31.6% of patients but was not associated with a lower rate of adequate occlusion.
Conclusions: This prospective, single-center series with WEB devices used in 39 patients during 3.5 years confirms data from previous multicenter studies. Treatment can be accomplished with good safety and efficacy, with a high rate of adequate occlusion. Anatomic results were not worse in case of WEB shape modification 5)