A systematic review and meta-analysis of Woven EndoBridge single layer for treatment of intracranial aneurysms

Embolization of Ruptured and Unruptured Aneurysms with the Contour Neurovascular System-Summary of 106 Cases

BACKGROUND AND PURPOSE

Aneurysmal disease of the intracranial vasculature poses a relevant threat, warranting effective interventions. Minimally invasive interventional techniques for aneurysm treatment have evolved to the application of flow-diversion stents and devices. This study focuses on the Contour Neurovascular System (CNS), aiming to add knowledge regarding its mid- to long-term outcomes in treating wide-necked intracranial aneurysms.

MATERIALS AND METHODS

Conducted in accordance with STROBE guidelines, this study retrospectively evaluated all patients with intracranial aneurysms treated with CNS embolization. Demographic and interventional data were collected retrospectively, including aneurysm characteristics, procedural details, and angiographic follow-up evaluations up to 24 months after CNS implantation.

RESULTS

A total of 106 patients with 109 aneurysms were included in this study, whereby 72 patients were treated for an incidental aneurysm, while 34 patients presented with subarachnoid hemorrhage. Implantation was successful in 95.5% of patients. Occlusion rates were as follows: 6 months (69/106, 65.1%): Raymond-Roy-Scale (RRS) 1 44/69 (63.4%), RRS 2 16/69 (23.1%), RRS 3a 4/69 (5.8%), RRS 3b 5/69 (7.2%); 12 months (44/106, 41.5%): RRS 1 24/44 (55.5%), RRS 2 12/44 (27.3%), RRS 3a 4/44 (9.0%), RRS 3b 4/44 (9.0%); 24 months (30/106, 28.3%): RRS 1 21/30 (70.0%), RRS 2 8/30 (26.7%), RRS 3b 1/30 (3.3%). Periprocedural complications: Overall 8/106 (7.5%); elective cases 4/72 (5.5%); aneurysm rupture 4/34 (11.7%). Adjunctive devices were used in 13/106 cases (12.2%).

CONCLUSIONS

The present work reports the long-term angiographic and clinical follow-up results of a single-center cohort of 106 patients with intracranial aneurysms treated with the CNS. The CNS demonstrated a high rate of successful implantation and promising mid- and long-term stability, with a low reintervention rate beyond 24 months in patients exhibiting early occlusion at 6 months. While acknowledging the limitations, these findings contribute valuable information about the safety and efficacy of the CNS, and warrant continued exploration in larger, prospective studies to validate its role in aneurysm treatment.

Embolization of an anterior communicating aneurysm with a Woven EndoBridge combined with a coil: a case report

Cases of Woven EndoBridge (WEB) combined with coil embolization of ruptured anterior communicating aneurysms are rare. We report a 56-year-old male patient who underwent WEB spoiler device combined with coil embolization for ruptured anterior communicating aneurysms and benefited from it. Considering that the patient's aneurysm had ruptured and immediate hemostasis was urgently needed, a coil was introduced to reduce the patient's bleeding risk, in an effort to achieve immediate hemostasis. Considering that the patient's aneurysm morphology was long and narrow, WEB alone was not enough to completely occlude the aneurysm. The combined use of coils can ensure that the aneurysm neck is properly occluded and the aneurysm head is completely embolized. This article details the preoperative evaluation of the patient's condition, the surgical plan, and the postoperative management. The results of this case confirm the feasibility of WEB combined with coil embolization in patients with ruptured aneurysms.

Machine Learning Algorithms to Predict the Risk of Rupture of Intracranial Aneurysms: a Systematic Review

PURPOSE

Subarachnoid haemorrhage is a potentially fatal consequence of intracranial aneurysm rupture, however, it is difficult to predict if aneurysms will rupture. Prophylactic treatment of an intracranial aneurysm also involves risk, hence identifying rupture-prone aneurysms is of substantial clinical importance. This systematic review aims to evaluate the performance of machine learning algorithms for predicting intracranial aneurysm rupture risk.

METHODS

MEDLINE, Embase, Cochrane Library and Web of Science were searched until December 2023. Studies incorporating any machine learning algorithm to predict the risk of rupture of an intracranial aneurysm were included. Risk of bias was assessed using the Prediction Model Risk of Bias Assessment Tool (PROBAST). PROSPERO registration: CRD42023452509.

RESULTS

Out of 10,307 records screened, 20 studies met the eligibility criteria for this review incorporating a total of 20,286 aneurysm cases. The machine learning models gave a 0.66-0.90 range for performance accuracy. The models were compared to current clinical standards in six studies and gave mixed results. Most studies posed high or unclear risks of bias and concerns for applicability, limiting the inferences that can be drawn from them. There was insufficient homogenous data for a meta-analysis.

CONCLUSIONS

Machine learning can be applied to predict the risk of rupture for intracranial aneurysms. However, the evidence does not comprehensively demonstrate superiority to existing practice, limiting its role as a clinical adjunct. Further prospective multicentre studies of recent machine learning tools are needed to prove clinical validation before they are implemented in the clinic.

Neck apposition is a key factor for aneurysm occlusion after Woven EndoBridge device embolization

BACKGROUND

Sealing of the aneurysm neck with a Woven EndoBridge (WEB) device is recommended for disrupting the blood flow inside the aneurysm. This study investigates the relationship between WEB neck apposition and aneurysm occlusion rates.

METHODS

Aneurysms treated with a WEB from March 2017 to May 2022 at a single center were included. WEB neck apposition (poor/good) and WEB protrusion (yes/no) were evaluated on post-detachment high resolution cone beam CT images. Angiographic occlusion was assessed with the Bicêtre Occlusion Scale score (BOSS). Univariate and multivariable analysis tested the association between neck apposition and occlusion rates.

RESULTS

The study included 159 aneurysms in 141 patients (mean age 55.8±11.2 years; 64.2% women). Good neck apposition and protrusion were noted in 123 (77.4%) and 30 (18.9%) cases, respectively. Inter-rater agreements were good for neck apposition (κ=0.75) and protrusion (κ=0.78). Complete and adequate occlusion was achieved in 104 (65%) and 130 (82%) cases, respectively (median follow-up 18 months). Good neck apposition was a strong independent predictor for both adequate (adjusted OR (aOR)=5.9, 95% CI 2.4 to 14.9; P<0.001) and complete occlusion (aOR=7.1, 95% CI 3.0 to 18.1; P<0.001). Protrusion was more frequent in the adequate occlusion group versus the aneurysm recurrence group without reaching statistical significance (P=0.06), but was associated with more thromboembolic complications (9/30 (30%) vs 12/129 (9%); P<0.01). WEB shape modification was significantly greater in poor apposition cases (P=0.03).

CONCLUSIONS

Achieving good neck apposition of the WEB strongly predicts aneurysm occlusion during follow-up. WEB protrusion should be minimized due to the increase in thromboembolic risk with limited impact on aneurysm occlusion.

The impact of postoperative aspirin in patients undergoing Woven EndoBridge: a multicenter, institutional, propensity score-matched analysis

BACKGROUND

The Woven EndoBridge (WEB) device is frequently used for the treatment of intracranial aneurysms. Postoperative management, including the use of aspirin, varies among clinicians and institutions, but its impact on the outcomes of the WEB has not been thoroughly investigated.

METHODS

This was a retrospective, multicenter study involving 30 academic institutions in North America, South America, and Europe. Data from 1492 patients treated with the WEB device were included. Patients were categorized into two groups based on their postoperative use of aspirin (aspirin group: n=1124, non-aspirin group: n=368). Data points included patient demographics, aneurysm characteristics, procedural details, complications, and angiographic and functional outcomes. Propensity score matching (PSM) was applied to balance variables between the two groups.

RESULTS

Prior to PSM, the aspirin group exhibited significantly higher rates of modified Rankin scale (mRS) mRS 0-1 and mRS 0-2 (89.8% vs 73.4% and 94.1% vs 79.8%, p<0.001), lower rates of mortality (1.6% vs 8.6%, p<0.001), and higher major compaction rates (13.4% vs 7%, p<0.001). Post-PSM, the aspirin group showed significantly higher rates of retreatment (p=0.026) and major compaction (p=0.037) while maintaining its higher rates of good functional outcomes and lower mortality rates. In the multivariable regression, aspirin was associated with higher rates of mRS 0-1 (OR 2.166; 95% CI 1.16 to 4, p=0.016) and mRS 0-2 (OR 2.817; 95% CI 1.36 to 5.88, p=0.005) and lower rates of mortality (OR 0.228; 95% CI 0.06 to 0.83, p=0.025). However, it was associated with higher rates of retreatment (OR 2.471; 95% CI 1.11 to 5.51, p=0.027).

CONCLUSIONS

Aspirin use post-WEB treatment may lead to better functional outcomes and lower mortality but with higher retreatment rates. These insights are crucial for postoperative management after WEB procedures, but further studies are necessary for validation.

Woven endo bridge device for recurrent intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

Recurrent intracranial aneurysms present a significant clinical challenge, demanding innovative and effective treatment approaches. The Woven EndoBridge (WEB) device has emerged as a promising endovascular solution for managing these intricate cases. This study aims to assess the safety and efficacy of the WEB device in treating recurrent intracranial aneurysms.

METHODS

We conducted a comprehensive search across multiple databases, including PubMed, Scopus, Embase, and Web of Science, from inception to June 5, 2023. Eligible studies focused on evaluating WEB device performance and included a minimum of five patients with recurrent intracranial aneurysms. The complete and adequate occlusion rates, neck remnant rates, and periprocedural complication rates were pooled using SATA V.17.

RESULTS

Our analysis included five studies collectively enrolling 73 participants. Participant ages ranged from 52.9 to 65 years, with 64.4% being female. Aneurysms were wide-necked and predominantly located in the middle cerebral artery, basilar artery, and anterior cerebral artery. Previous treatments encompassed coiling, clipping, and the use of WEB devices. Our study found an overall adequate occlusion rate of 0.80 (95% CI 0.71-0.89), a complete occlusion rate of 0.39 (95% CI 0.28-0.50), and a neck remnant rate of 0.38 (95% CI 0.27-0.48). Periprocedural complications were reported at a rate of 0%, although heterogeneity was observed in this data. Notably, evidence of publication bias was identified in the reporting of periprocedural complication rates.

CONCLUSION

Our findings suggest that the WEB device is associated with favorable outcomes for treating recurrent wide-neck intracranial aneurysms.

Intrasaccular Treatment of Intracranial Aneurysms: A Comprehensive Review

Background: The endovascular treatment of complex intracranial aneurysms, such as wide-neck aneurysms (WNAs), remains a challenge. More established endovascular techniques, which include balloon-assisted coiling, stent-assisted coiling, and flow diversion, all have their drawbacks. Intrasaccular flow disruptor devices have emerged as a useful tool for the neurointerventionalist. Methods: Here, we discuss landmark studies and provide a comprehensive, narrative review of the Woven EndoBridge (WEB; Microvention, Alisa Viejo, CA, USA), Artisse (Medtronic, Irvine, CA, USA), Contour (Stryker, Kalamazoo, MI, USA), Saccular Endovascular Aneurysm Lattice Embolization System (SEAL; Galaxy Therapeutics Inc, Milpitas, CA, USA), Medina (Medtronic, Irvine, CA, USA), and Trenza (Stryker, Kalamazoo, MI, USA) devices. Results: Intrasaccular devices have proven to be effective in treating complex aneurysms like WNAs. Conclusions: Intrasaccular flow disruptors have emerged as a new class of effective endovascular therapy, and results of ongoing clinical studies for the newer devices (e.g., SEAL and Trenza) are much anticipated.

Intrasaccular Flow Disruption: Examining Global Access and Research Trends

The Woven EndoBridge (WEB) and other intrasaccular flow disruptors show promise in treating intracranial aneurysms. We performed a bibliometric analysis to provide novel insights into the trends and trajectory of these devices. We systematically assessed bibliometric data such as citations, journals, study designs, open access status, and multi-institutional involvement for the top-cited articles on WEB and other disruptors. The top 100 cited studies on the WEB had citations from 7 to 144 (mean ± standard deviation 35.6 ± 29.5), while only 33 studies were published for other intrasaccular flow disruptors (4.24 ± 8.45). Of the other devices, the Contour has the most publications (n = 21). Retrospective reviews were the most common study design for both WEB and other intrasaccular devices. France published the most studies in the top 100 WEB papers (n = 35), while Germany led for other flow disruptors (n = 10). In all studies analyzed, no senior authors from Africa are present. The top 100 WEB publications had a higher mean citation count (35.6 vs. 4.24, P<0.001), higher mean citations per year (5.24 vs. 1.03, P<0.01), and a higher proportion of multi-institutional collaborations (44.0% vs. 12.1%, P<0.01) than other intrasaccular flow disruptors. In conclusion, countries with the most publications on WEB are not necessarily the ones leading the way with newer intrasaccular devices, while study designs remain similar. There is a limited contribution to the literature outside of Europe and North America. Our findings identify notable collaborators and trends, providing a snapshot of the field and a roadmap for future research.

Variability patterns in dual antiplatelet therapy following endovascular repair of intracranial aneurysms: Insight into regimen heterogeneity and the need for a consensus

This comprehensive review delves into the evolving field of neurointervention for intracranial aneurysms, exploring the critical adjunct of Dual Antiplatelet Therapy (DAPT) to endovascular coiling, stent-assisted coiling (SAC), flow-diversion stents, and flow-disruption (intrasaccular) devices. Despite growing evidence supporting the success of DAPT in reducing thromboembolic events, the lack of consensus on optimal regimens, doses, and duration is evident. Factors contributing to this variability include genetic polymorphisms affecting treatment response and ongoing debates regarding the clinical significance of hemorrhagic complications associated with DAPT. This review analyzes pre- and post-procedural antiplatelet usage across various interventions. The imperative lies in ongoing research to define optimal DAPT durations, ensuring a nuanced approach to the delicate balance between thrombosis and hemorrhage in intracranial aneurysm management.

Rescue Stenting for Inadvertent Branch Vessel Occlusion Following Cerebral Aneurysm Embolization With the Woven EndoBridge Device

Intrasaccular flow modification with devices like the Woven EndoBridge (WEB, MicroVention, Inc., Aliso Viejo, California, US) is an increasingly utilized endovascular treatment for bifurcation aneurysms. Among the potential complications of the procedure is branch vessel occlusion. There are no previous publications of rescue stenting for inadvertent branch vessel occlusion with the WEB device. We report two cases of rescue stenting following branch vessel occlusion after cerebral aneurysm embolization with the WEB device. In both cases, rescue stenting with a Neuroform Atlas stent Stryker, Fremont, CA, US) successfully revascularized the occluded vessel and led to good patient outcomes.

A large UK single-centre experience in the long-term safety and efficacy of Woven Endobridge in the treatment of wide-neck intracranial aneurysms and risk factors associated with re-bleeding and re-treatment

INTRODUCTION

Endovascular treatment of wide neck aneurysms remains complicated with a determined and continuous technological effort towards treatment options that can offer safer and efficacious outcomes. The Woven Endobridge device was introduced in 2010 and has become a mainstay endovascular treatment for wide neck and large intracranial aneurysms. A recent review of the Woven Endobridge Clinical Assessment of Intrasaccular Aneurysm Therapy (WEBCAST) and WEBCAST2 trials and the five-year follow-up of patients was published. Our aim is to demonstrate real-life experience of aneurysms and patients treated with Woven Endobridge from a large high-volume specialist centre.

METHODS

A retrospective review was performed of patients treated with Woven Endobridge from March 2013 to March 2018. Primary efficacy outcomes were defined as per Raymond-Roy Occlusion Criteria (RROC) resulting in long-term complete occlusion (RROC1) and adequate occlusion (RROC1 and RROC2). Primary Safety outcomes were defined as procedure-related morbidity, rate of re-bleeding and rate of re-treatment.

RESULTS

Seventy-nine aneurysms were treated during the five-year period. Adequate aneurysm occlusion (RROC1 and RROC2) achieved was 81%. Retreatment was required in 18% of patients (14/79). Greater retreatment rate was demonstrated in partially thrombosed aneurysms, aneurysms with larger neck and dome diameter and dome heights.

CONCLUSION

Woven Endobridge treatment of wide-neck intracranial aneurysms offers a safe and efficacious outcome. This large UK single-centre experience demonstrates congruity with recent five-year outcomes of WEBCAST and WEBCAST2 trials.

WEB embolization of very broad-based intracranial aneurysms with a dome-to-neck ratio ≤ 1.1

OBJECTIVE

The Woven EndoBridge (WEB) is a well-studied intrasaccular device for endovascular treatment of wide-necked bifurcation aneurysms. We evaluated the feasibility, safety and efficacy of the WEB for the treatment of very broad-based aneurysms with a dome-to-neck ratio ≤ 1.1.

METHODS

Thirty-four aneurysms treated at three neurovascular centers were retrospectively identified. The mean aneurysm size was 5.5 ± 1.6 mm with a mean neck width of 4.7 ± 1.5 and a mean dome-to-neck ratio of 1.0 ± 0.1. The primary outcome measures were immediate technical treatment success by WEB only, complete or near-complete occlusion at 6-month follow-up and ischemic stroke.

RESULTS

Aneurysm embolization by WEB only was technically feasible in 79.4%. Additional stenting was required in 14.7%. In two aneurysms (5.9%), WEB implantation failed, and the aneurysm was treated by stent- and balloon-assisted coiling, respectively. Thromboembolic events occurred during 5 interventions (14.7%), all of these performed in ruptured aneurysms. One patient (2.9%) remained asymptomatic (follow-up modified Rankin scale [mRS] score: 0), 2 patients (5.9%) had a transient deficit (mRS 0 and 1, respectively), and 2 (5.9%) had a disabling ischemic stroke (mRS 3, respectively). Mid-term angiographic follow-up of 29 patients (4.0 ± 2.6 months, range: 2-9 months) showed complete occlusion (WEB occlusion scale [WOS] A) in 41.4%, near-complete occlusion (WOS B) in 34.5%, a neck remnant (WOS C) in 10.3%, and aneurysm remnants (WOS D) in 13.8%.

CONCLUSIONS

WEB embolization of very broad-necked aneurysms was technically feasible and could be achieved by WEB only in the majority of cases. Considering the challenging anatomy of very broad-based aneurysms, the WEB procedure was reasonably safe and efficient.

Dual Layer vs Single Layer Woven EndoBridge Device in the Treatment of Intracranial Aneurysms: A Propensity Score-Matched Analysis

BACKGROUND

The Woven EndoBridge (WEB) devices have been used for treating wide neck bifurcation aneurysms (WNBAs) with several generational enhancements to improve clinical outcomes. The original device dual-layer (WEB DL) was replaced by a single-layer (WEB SL) device in 2013. This study aimed to compare the effectiveness and safety of these devices in managing intracranial aneurysms.

METHODS

A multicenter cohort study was conducted, and data from 1,289 patients with intracranial aneurysms treated with either the WEB SL or WEB DL devices were retrospectively analyzed. Propensity score matching was utilized to balance the baseline characteristics between the two groups. Outcomes assessed included immediate occlusion rate, complete occlusion at last follow-up, retreatment rate, device compaction, and aneurysmal rupture.

RESULTS

Before propensity score matching, patients treated with the WEB SL had a significantly higher rate of complete occlusion at the last follow-up and a lower rate of retreatment. After matching, there was no significant difference in immediate occlusion rate, retreatment rate, or device compaction between the WEB SL and DL groups. However, the SL group maintained a higher rate of complete occlusion at the final follow-up. Regression analysis showed that SL was associated with higher rates of complete occlusion (OR: 0.19; CI: 0.04 to 0.8, p = 0.029) and lower rates of retreatment (OR: 0.12; CI: 0 to 4.12, p = 0.23).

CONCLUSION

The WEB SL and DL devices demonstrated similar performances in immediate occlusion rates and retreatment requirements for intracranial aneurysms. The SL device showed a higher rate of complete occlusion at the final follow-up.

Systematic Review and Meta-Analysis of Endovascular Therapy Effectiveness for Unruptured Saccular Intracranial Aneurysms

Background

Currently, endovascular treatment of intracranial aneurysms (ICAs) is limited by low complete occlusion rates. The advent of novel endovascular technology has expanded the applicability of endovascular therapy; however, the superiority of novel embolic devices over the traditional Guglielmi detachable coils (GDCs) is still debated. We performed a systematic review of literature that reported Raymond-Roy occlusion classification (RROC) rates of modern endovascular devices to determine their immediate and follow-up occlusion effectiveness for the treatment of unruptured saccular ICAs.

Methods

A search was conducted using electronic databases (PUBMED, Cochrane, ClinicalTrials.gov, Web of Science). We retrieved studies published between 2000-2022 reporting immediate and follow-up RROC rates of subjects treated with different endovascular ICA therapies. We extracted demographic information of the treated patients and their reported angiographic RROC rates.

Results

A total of 80 studies from 15 countries were included for data extraction. RROC rates determined from angiogram were obtained for 21,331 patients (72.5% females, pooled mean age: 58.2 (95% CI: 56.8-59.6), harboring 22,791 aneurysms. The most frequent aneurysm locations were the internal carotid artery (46.4%, 95% CI: 41.9%-50.9%), the anterior communicating artery (26.4%, 95% CI: 22.5%-30.8%), the middle cerebral artery (24.5%, 95% CI:19.2%-30.8%) and the basilar tip (14.4%, 95% CI:11.3%-18.3%). The complete occlusion probability (RROC-I) was analyzed for GDCs, the Woven EndoBridge (WEB), and flow diverters. The RROC-I rate was the highest in balloon-assisted coiling (73.9%, 95% CI: 65.0%-81.2%) and the lowest in the WEB (27.8%, 95% CI:13.2%-49.2%). The follow-up RROC-I probability was homogenous in all analyzed devices.

Conclusions

We observed that the coil-based endovascular therapy provides acceptable rates of complete occlusion, and these rates are improved in balloon-assisted coils. Out of the analyzed devices, the WEB exhibited the shortest time to achieve >90% probability of follow-up complete occlusion (~18 months). Overall, the GDCs remain the gold standard for endovascular treatment of unruptured saccular aneurysms.

Endovascular Treatment of Bifurcation Aneurysms with the Woven EndoBridge: Product Features and Selected Results of Off-Label Use

Treatment for wide-neck bifurcation cerebral aneurysms (WNBAs) is widely performed by endovascular treatment as well as open surgical clipping. However, due to factors such as the shape and size of the aneurysms, as well as the anatomical features of surrounding branch vessels, there are some cases in which simple coiling or conventional adjunctive techniques, such as balloon-assisted or neck bridge stent-assisted coiling, are not sufficient to achieve a satisfactory cure. Against this backdrop, the device known as the Woven EndoBridge (WEB) (MicroVention, Aliso Viejo, CA, USA) was developed and can be deployed directly into the aneurysm for treatment. Over a decade has passed since its development, and it is now used in many countries worldwide. This review provides insights into the evolution of the WEB device from its development to the date of this writing, highlighting the unique features of the device and its treatment indications. Additionally, it discusses the posttreatment course, perspectives on recurrence and retreatment, imaging assessments, and potential off-label use based on numerous studies primarily conducted in Europe and the USA.

Thromboembolic Events With the Woven Endobridge Device: Incidence, Predictive Factors, and Management

BACKGROUND AND OBJECTIVES

The Woven EndoBridge (WEB) device has been increasingly used to treat wide-neck aneurysms showing a safe and effective profile, but a relatively high number of thromboembolic events (TEEs) have been reported with such treatment. We aimed to evaluate the incidence and management of TEEs and possible predictive factors related to WEB embolization of ruptured and unruptured intracranial aneurysms.

METHODS

A single-center database with consecutive aneurysms treated with a WEB device between July 2012 and May 2022 was reviewed for intraoperative and delayed TEEs. Univariate and multivariable analyses were used to determine factors associated with TEEs.

RESULTS

A total of 266 independent aneurysms were treated with WEB devices in 245 patients (mean age 55.78 ± 11.64 years, 169 (63.5%) females, 80 (30%) ruptured). The overall rate of TEEs is 13% (35/266), including 8.7% intraoperative. Symptomatic TEEs with clinical sequelae at a 3-month follow-up are reported to be 2.6% (7/266) with no TEE-related mortality. Both the replacement of a WEB device during the procedure (adjusted odds ratio = 2.61, 95% CI 1.24-5.49; P = .01) and ruptured aneurysms (adjusted odds ratio = 2.74, 95% CI 1.31-5.7; P = .007) were independent predictors of TEEs. A case-by-case management of intraprocedural TEE is also presented; tirofiban was successfully used in most cases of this cohort.

CONCLUSION

In this study, we demonstrated that ruptured aneurysms and WEB device replacement during the procedure were independent predictive factors for TEEs. As a result, making the correct choice of WEB is crucial for improving treatment outcomes. Moreover, with proper medical management of TEEs, minimal morbidity and no mortality could be achieved, which reinforces the safety of the technique.

Woven EndoBridge Device for Unruptured Wide-Neck Bifurcation Aneurysm: A Multicenter 5-Year Follow-up

BACKGROUND AND OBJECTIVES

This multicenter study aimed to assess the safety and efficacy of the Woven EndoBridge (WEB) device for treating unruptured wide-neck intracranial bifurcation aneurysms (WIBAs) with short-, mid-, and long-term follow-ups (FUPs).

METHODS

Consecutive patients with unruptured WIBAs treated with WEB between December 2014 and January 2018 were included. Patient, aneurysm, and device characteristics were collected and analyzed retrospectively. Morbidity and mortality rates were determined by collecting intraprocedural, periprocedural, and delayed complications. Aneurysm occlusion was assessed at 1, 3, and 5 years using a 3-grade scale: complete occlusion, neck remnant, and residual aneurysm. Complete occlusion and neck remnant were considered as adequate occlusion. Patients who received re-treatment were also evaluated.

RESULTS

The study included 104 consecutive patients (55.8% female, mean age 58.6 ± 11.8 years). Aneurysm maximum size, neck, and dome-to-neck mean were, respectively, 6.9 ± 2.1 mm, 4.5 ± 1.2 mm, and 1.4 ± 0.3 mm. One-year FUP was collected for 95 patients, and 3- and 5-year FUPs were collected for 83 patients. Adequate occlusion was observed at 1-year FUP in 90.5% (86/95), 91.6% (76/83) was observed at 3-year FUP, and 92.8% (77/83) at 5-year FUP. None of the aneurysms bled after treatment. During FUP, 6/83 patients (7.2%) were re-treated for residual aneurysm. Morbidity and mortality rates closely related to aneurysm occlusion were 0% (0/104).

CONCLUSION

The WEB device was safe and effective for treating unruptured WIBAs, both in short-term and long-term FUPs.

The Safety and Efficacy of eCLIPs for Treatment of Wide-Necked Bifurcation Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND

Wide-necked bifurcation aneurysms (WNBAs) are challenging intracranial aneurysms. Several device and treatment approaches have been proposed for the treatment of WNBAs. The endovascular clip system (eCLIPs) is a newly developed endovascular device with flow diverter and flow disruptor features. This study aims to investigate the safety and efficacy of the eCLIPs for treatment of patients with WNBAs.

METHODS

This is a systematic review and meta-analysis study conducted in accordance with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines. The electronic databases of PubMed, Embase, Scopus, and Web of Science were systematically reviewed from inception to June 19, 2023. The rate of complete and near-complete occlusion, successful device implantation, and serious adverse events were pooled using STATA, version 17.

RESULTS

A total of 5 studies with 110 patients with WNBAs were systematically investigated. Our findings show that the immediate successful implantation rate of eCLIPs was 0.93 (95% confidence interval [CI], 0.88-0.97). Moreover, the immediate postoperative complete occlusion rate was 0.34 (95% CI, 0.10-0.58), and the immediate postoperative near-complete occlusion rate was 0.35 (95% CI, 0.24-0.45). Also, the near-complete occlusion rate at the latest follow-up was 0.3 (95% CI, 0.16-0.44). The serious adverse event rate was 0.14 (95% CI, 0.05-0.22). Stroke was also reported in 2 studies, with 1 study reporting 1 patient who experienced stroke within the first 24 hours and 1 study reporting no patients with stroke.

CONCLUSIONS

Our findings document that the eCLIPs is a safe and effective device for treating patients with WNBAs and associated with favorable outcomes.

Endovascular treatment of wide-necked intracranial aneurysms using the Nautilus Intrasaccular System: initial case series of 41 patients at a single center

BACKGROUND

Endovascular treatment of intracranial wide-necked and bifurcation aneurysms (WNBA) is technically challenging. The Nautilus Intrasaccular System is designed to provide a mechanical barrier at the aneurysm neck to support coil embolization. We report the results of a single-center series of patients treated for intracranial aneurysms with the Nautilus.

METHODS

Clinical and radiological data were retrospectively collected for all patients treated with the Nautilus for an unruptured or ruptured intracranial aneurysm at our center between March 2021 and March 2022. Clinical outcomes (modified Rankin Scale (mRS) scores), Raymond-Roy angiographic occlusion, recanalization, and complications were measured immediately post-procedure and at 3-6-month follow-up.

RESULTS

A total of 41 patients of mean age 56.7 years (range 37-83 years) were treated with the Nautilus, with 41 saccular aneurysms (18 (43.9%) unruptured and 23 (56.1%) ruptured). The majority of aneurysms (39/41 (95.1%)) were located in the anterior circulation. We experienced no technical complications. One patient had an asymptomatic post-procedural minor stroke related to the procedure. Immediate Class I occlusion was achieved in 30 (73.1%) patients. The rate of all-cause mortality was 7.3% (3/41). One patient was lost to follow-up. At follow-up, 94.5% (35/37) of patients achieved Class I occlusion and 94.5% (35/37) had an mRS score of 0. There were no procedural-related deaths or permanent morbidities at discharge or follow-up.

CONCLUSION

This study demonstrates good safety and effectiveness using the Nautilus Intrasaccular System to treat both ruptured and unruptured intracranial aneurysms. Larger studies are needed to confirm these findings.

The Woven EndoBridge (WEB) Device for the Treatment of Intracranial Aneurysms: Ten Years of Lessons Learned and Adjustments in Practice from the WorldWideWEB Consortium

Several studies have shown promising outcomes of the Woven EndoBridge (WEB) device for the treatment of wide-necked intracranial bifurcation aneurysms. This is a multicenter study attempts to explore the changes in trends and treatment outcomes over time for WEB embolization of intracranial aneurysms. The WorldWideWEB consortium is a retrospective multicenter collaboration of data from international centers spanning from January 2011 and June 2021, with no limitations on aneurysm location or rupture status. Both bifurcation and sidewall aneurysms were included. These patients were stratified based on treatment year into five treatment intervals: 2011-2015 (N = 66), 2016-2017 (N = 77), 2018 (N = 66), 2019 (N = 300), and 2020-2021 (N = 173). Patient characteristics and angiographic and clinical outcomes were compared between these time intervals. This study comprised 671 patients (median age 61.4 years; 71.2% female) with 682 intracranial aneurysms. Over time, we observed an increasing tendency to treat patients presenting with ruptured aneurysms and aneurysms with smaller neck, diameter, and dome widths. Furthermore, we observed a trend towards more off-label use of the WEB for sidewall aneurysms and increased adoption of transradial access for WEB deployment. Moreover, the proportion of patients with adequate WEB occlusion immediately and at last follow-up was significantly higher in more recent year cohorts, as well as lower rates of compaction and retreatment. Mortality and complications did not differ over time. This learning curve study suggests improved experience using the WEB for the treatment of intracranial aneurysms and has yielded higher rates of adequate occlusion over time.

WEB (Woven EndoBridge) device for intracranial aneurysm treatment: technical, radiological, and clinical findings in a consecutive North American cohort

BACKGROUND

Utilization of Woven EndoBridge (WEB) for treatment of intracranial aneurysms has increased due to increasing operator experience. We aimed to report our contemporary series of a North American center with the WEB, examining factors associated with occlusion rates.

METHOD

Consecutive patients (2019-2022) with intracranial aneurysms treated with WEB device were included. Through a univariate and multivariate analysis, independent predictors of adequate occlusion (RR1/RR2) were examined. Procedural and clinical results were reported.

RESULTS

A total of 104 consecutive aneurysms/patients (25 men/79 women; median age, 63 years, IQR: 55-71) were treated with single-layer WEB-SL in our institution. Seventeen patients (16%) had a ruptured aneurysm. The median aneurysm dome size was 5.5 mm (IQR = 4.5-6.5), and the most common locations were AcomA (36/104 = 34.6%), MCA bifurcation (29/104 = 27.9%), and BT (22/104 = 21.2%). The rate of technical failure was 0.9%. The median intervention time was 32 min (IQR = 25-43). Overall, 8 (7.6%) cases needed additional interventions: 4 (3.8%) additional stenting, 3 cases (3.8%) of intravenous tirofiban infusion (because of the excessive WEB protrusion), and one case (0.9%) of additional coiling (need to complete the neck occlusion). At 12-month follow-up, 67 patients were available showing 59/67 (88%) and 6/67 (9%) of complete occlusion and neck remnant, respectively on dual-energy CTA. There were no cases necessitating retreatment. Ruptured presentation (OR = 0.09, 95% CI = 0.008-0.9, p = .024), undersized WEB (OR = 15, 95% CI = 1.2-50, p = .006), WEB shape change (OR = 0.07, 95% CI = 0.001-0.6, p = .05), aneurysm neck diameter (OR = 0.4, 95% CI = 0.2-0.9, p = .05), and angle between the parent artery and the aneurysm dome (OR = 0.2, 95% CI = 0.01-0.8, p = .008) were significantly associated with occlusion status (RR1-2) at follow-up. However, in the multivariate logistic regression, these factors did not reach the statistical significance. The overall rate of morbidity was 0.9%.

CONCLUSIONS

Our contemporary North American experience on consecutive intracranial aneurysms treated with WEB confirms the medium-term efficacy of this strategy, with low procedural time and morbidity. Further research is needed to demonstrate long-term occlusion rates.

A review and journey in intrasaccular treatment of intracranial aneurysms

The invested effort and collaboration of clinicians and medical device companies to improve occlusion rates and clinical outcomes for patients with intracranial aneurysms treated via less invasive endovascular means led to the development of the concept of intrasaccular devices. Intrasaccular devices were introduced to offer simple treatment options, offering easier navigation through difficult anatomy, simpler and quicker deployment into large and wide-neck aneurysms. Additionally, they offer easier sizing, whilst offering a wide range of options suitable for aneurysms of different sizes. The concept of most intrasaccular devices is to occupy the aneurysm neck, however offering better stability than simple coiling, therefore increasing the chance of long-term aneurysm occlusion. This is achieved without a sizable metal content within the parent vessel, contrary to flow diverters, theoretically reducing the risk of thromboembolic events. This review aims to discuss the history and latest developments of intrasaccular intracranial devices, which offer an exciting and potentially successful option for treatment of complex intracranial aneurysms.

Persistent contrast-filling in the woven endobridge device three months after its implantation for cerebral aneurysm: Incidence, predictive factors, and outcome

OBJECTIVE

The Woven EndoBridge (WEB) was developed to treat wide-neck bifurcation intracranial aneurysms. Occasionally, persistent contrast-filling has been observed in the WEB after treatment. The purpose of our study was to investigate its incidence, predictive factors, and clinical impact.

METHODS

All patients treated with the WEB between January 2021 and September 2021 at our institute were reviewed. Age, gender, antiplatelet therapy, and angioarchitecture were compared between the persistent-filling group and the no-filling group at the three-month follow-up angiography.

RESULTS

We included 20 patients with 20 unruptured aneurysms. Ten of the 20 intracranial aneurysms (50 %) showed contrast-filling in the WEB after three months. Two of the 10 had contrast not only inside, but around the device. Statistically significant differences were observed between the persistent-filling group and the no-filling group in neck size (median: 4.5 mm vs. 3.8 mm), deviation of the aneurysm axis from the inlet flow line where the orifice of the bifurcated arteries overlaps (mean: 15.1° vs. 33.0°), and postoperative dual antiplatelet therapy (DAPT) for at least a month (90 % vs. 20 %). One case had additional coil embolization six months after the WEB implantation. Including this case, one year after the treatment or the re-treatment, the filling in the device had disappeared in nine of 10 cases. No bleeding was observed during the mean follow-up period of 24 months.

CONCLUSION

Persistent contrast-filling was associated with postoperative DAPT for at least a month, a wide neck, and less deviation of the aneurysm axis from the inlet flow line. If the contrast-filling is only within the WEB and not between the aneurysmal wall and the WEB, we are not concerned. To further assess the clinical impact of this phenomenon, long-term follow-up will be needed.

Trends of Expanding Indications of Woven EndoBridge Devices for the Treatment of Intracranial Aneurysms: A Systematic Review and Meta-analysis

PURPOSE

Woven EndoBridge (WEB) was introduced for the endovascular therapy of wide-neck intracranial aneurysms. The safety and efficacy have been evaluated through several meta-analyses. However, these reviews did not cover the expanding indications in detail. Therefore, we aimed to show the changing trends for intracranial aneurysm treatment using the WEB device.

METHODS

A systematic review and meta-analysis was conducted with PubMed, Embase, and Cochrane databases. We searched for studies that reported baseline characteristics of aneurysms and the WEB devices, which had treated more than 20 aneurysms consecutively. The pooled proportions of aneurysm indications and used WEB device types were obtained. To evaluate the changing indications for the treated aneurysm size, including the neck diameter, a trend line and linear regression model was measured.

RESULTS

A total of 27 cohorts were included encompassing 1831 aneurysms treated with the WEB. A total of 86% were used in the four major locations as on-label indications (middle cerebral artery bifurcation; 34%, anterior communicating artery; 26%, basilar tip; 18%, internal carotid artery terminus; 7%). Among off-label indications, the most common location was the posterior communicating artery (8%), followed by the anterior cerebral artery including the pericallosal artery (6%). The median aneurysm size and neck diameter was 7 mm and 4.6 mm, respectively. The WEB device has been used for the treatment of smaller aneurysms than the initial indication. Also, the proportion for ruptured aneurysm treatment was increased up to 15%.

CONCLUSION

The mechanical and technical development of the WEB resulted in expanding the indications for the treatment of intracranial aneurysms. The off-label indications accounted for 14% in total and an increasing number of small aneurysms are treated with WEB devices. Moreover, the proportion for ruptured aneurysm treatment was currently increased up to 14% more than in the beginning.

Heterogeneous model to evaluate CFD in intracranial bifurcation aneurysms treated with the WEB device to predict angiographic outcome

INTRODUCTION

The Woven EndoBridge device (WEB) was developed as an alternative to treat Wide-Necked bifurcation aneurysms. It has proven to be effective and safe, however, cases of recanalization have been reported. The purpose of this study was to evaluate and quantify hemodynamic parameters and indexes with CFD of the intracranial aneurysms before and after WEB simulation and to establish their relationship to complete occlusion.

MATERIALS AND METHODS

Using the heterogeneous model based on the marching cubes algorithm, we created 3D representations of 27 bifurcated intracranial aneurysms treated with the single-layer WEB device to evaluate hemodynamics parameters with CFD, calculated with and without the WEB.

RESULTS

We observed a lower treatment entry concentration indices (ICI) (2.12 ± 1.31 versus 3.14 ± 0.93, p-value: 0.029) previous to placement of WEB and higher pre-treatment FN (7.56 ± 5.92 versus 3.35 ± 1.51, p-value: 0.018) and post-treatment FN (5.34 ± 5.89 versus 1.99 ± 0.83, p-value: 0.021) for cases with successful occlusions. Lower post-treatment SRa (197.81 ± 221.29 versus 80.02 ± 45.25, p-value: 0.044) and higher pre (0.11 ± 0.07 versus 0.25 ± 0.19, p-value: 0.011) and post-treatment MATT (0.69 ± 1.23 versus 1.02 ± 0.46, p-value: 0.006) were observed in non-occluded cases.

CONCLUSIONS

In our CFD analysis of the hemodynamic parameters of IA, we found lower ICI before the placement of the WEB device and higher FN pre- and post-treatment for cases with successful occlusions. Non-occluded cases had lower post-treatment SRa and higher pre-treatment and post-treatment MATT.

Use of the Woven EndoBridge Device for Sidewall Aneurysms: Systematic Review and Meta-analysis

BACKGROUND

The Woven EndoBridge device was originally approved to treat intracranial wide-neck saccular bifurcation aneurysms. Recent studies have suggested its use for the treatment of sidewall intracranial aneurysms with variable success.

PURPOSE

Our aim was to evaluate the safety and efficacy of the Woven EndoBridge device for sidewall aneurysms using a meta-analysis of the literature.

DATA SOURCES

We performed a systematic review of all studies including patients treated with the Woven EndoBridge device for sidewall aneurysms from inception until May 2022 on Scopus, EMBASE, MEDLINE, the Web of Science, and the Cochrane Central Register of Controlled Trials.

STUDY SELECTION

Ten studies were selected, and 285 patients with 288 sidewall aneurysms were included.

DATA ANALYSIS

A random-effects meta-analysis of proportions using a generalized linear mixed model was performed as appropriate. Statistical heterogeneity across studies was assessed with I2 statistics.

DATA SYNTHESIS

The adequate occlusion rate at last follow-up was 89% (95% CI, 81%-94%; I2, = 0%), the composite safety outcome was 8% (95% CI, 3%-17%; I2 = 34%), and the mortality rate was 2% (95% CI, 1%-7%; I2 = 0%). Aneurysm width (OR = 0.5; P = .03) was the only significant predictor of complete occlusion.

LIMITATIONS

Given the level of evidence, our results should be interpreted cautiously until confirmation from larger prospective studies is obtained.

CONCLUSIONS

The initial evidence evaluating the use of the Woven EndoBridge device for the treatment of wide-neck sidewall intracranial aneurysms has demonstrated high rates of adequate occlusion with low procedural complications. Our findings favor the consideration of the Woven EndoBridge device as an option for the treatment of sidewall aneurysms.

Geometry of intracranial aneurysms and of intrasaccular devices may influence aneurysmal occlusion rates after endovascular treatment

INTRODUCTION

The Woven EndoBridge device (WEB) is used to treat wide-neck bifurcation aneurysms. These devices are deployed inside the sac. Therefore, the mesh structure provides apposition with the aneurysm wall and induces aneurysmal thrombosis. The objective of our study was to evaluate the anatomic and device-related parameters and indexes with Computational Fluid Dynamics (CFD) of the intracranial aneurysms before and after WEB simulation and find their relationship to complete occlusion.

MATERIALS AND METHODS

Using the heterogeneous model based on the marching cubes algorithm, we created 3D representations of 27 bifurcated intracranial aneurysms treated with the single-layer WEB device to evaluate anatomic and device-related parameters with CFD.

RESULTS

In our CFD analysis, we observed higher large volumes (Va) (0.25 ± 0.18 versus 0.39 ± 0.09, p-value= 0.025) and higher volume to neck surface ratio (Ra) (1.32 ± 0.17 versus 1.54 ± 0.14, p-value= 0.021) in cases with occlusion failure.

CONCLUSIONS

Large aneurysm volumes (Va) and higher volume to neck surface ratio (Ra) could be associated with occlusion failure in aneurysms treated with the WEB device.

A mini-review of intrasaccular flow diverters

Treatment of wide-necked complex intracranial aneurysms continues to challenge neurointerventionalists. Intrasaccular flow diverters have expanded the armamentarium considerably and are now used extensively. While five types of devices have already obtained the CE mark for use within Europe, only the Woven EndoBridge (WEB) device is approved by the US Food and Drug Administration. Other intrasaccular devices are the Luna/Artisse Aneurysm Embolization System (Medtronic), the Medina Embolic Device (Medtronic), the Contour Neurovascular System (Cerus), and the Neqstent Coil Assisted Flow Diverter (Cerus). This mini review will provide a compact overview of these devices and a summary of the current literature.

Utility of low-profile visualized intraluminal support (LVIS™) stent for treatment of acutely ruptured bifurcation aneurysms: A single-center study

Objective

Stent-assisted coiling has been increasingly used in the treatment of intracranial aneurysms. However, its application in ruptured bifurcation aneurysms remains controversial and challenging. This study aimed to present the safety and feasibility of low-profile visualized intraluminal support (LVIS™, LVIS, and LVIS Jr.) stent for acutely ruptured bifurcation aneurysms.

Methods

A total of 41 patients with acutely ruptured intracranial aneurysms arising at the bifurcation were treated with LVIS™ stent-assisted coiling in our hospital between January 2017 and December 2021. The clinical data and angiographic results of the patients were analyzed.

Results

Among these patients, all stents were successfully implanted. According to the immediate angiographic results, 29 aneurysms (70.7%) were completely occluded. Intraoperative thrombosis and hemorrhage occurred in two and one cases, respectively. No post-operative thrombosis or rebleeding events were observed. The clinical follow-up of all patients revealed that 38 (92.7%) cases had favorable outcomes (modified Rankin scale: 0-2). The angiographic results available for the 36 patients during the follow-up period revealed complete occlusion was achieved in 30 patients (83.3%) and residual neck in six patients.

Conclusion

The LVIS™ stent-assistant coiling is a safe and feasible option for acutely ruptured bifurcation aneurysms. Further studies with a prospective design, a larger sample size, and long-term follow-up are needed to validate these findings.

[pConus device for endovascular treatment of basilar bifurcation aneurysms]

Aneurysm occlusion with microcoils is an effective and safe procedure. However, bifurcation aneurysms usually have a wide neck, and their occlusion is still a difficult objective.

OBJECTIVE

To evaluate the efficacy and safety of bifurcation stents in the treatment of basilar bifurcation aneurysms.

MATERIAL AND METHODS

A retrospective analysis included 34 patients with basilar bifurcation aneurysms between 2016 and 2022. The pConus bifurcation stent was used as a stent-assistance for endovascular occlusion of aneurysms with microcoils. We analyzed technical features of stent implantation and clinical results of endovascular treatment. Mean aneurysm dimension was 8.4 mm, neck size - 4.6 mm. Preoperative MSR score 0-2 was observed in 94.7% of patients, 3-5 scores - in 5.3% of patients.

RESULTS

There were no significant changes in functional status early after surgery (MSR grading system). Total aneurysm occlusion was achieved in 67.6% of patients, subtotal - 17.6% of cases, partial - 14.8%. There were no technical or early postoperative clinical complications. Six months after surgery, total occlusion was observed in 77.8% of patients, subtotal occlusion - 14.8%, partial occlusion - 4%. MSR score 0-2 was observed between 3 and 12 months after surgery. One patient died from other cause rather aneurysm. Redo intervention due to aneurysm recanalization was performed in 1 patient.

CONCLUSION

The pConus bifurcation stent is effective and safe in endovascular treatment of basilar bifurcation aneurysms of the most complex configuration. There was a minimal risk of aneurysm recanalization in long-term postoperative period.

Long-term efficacy and safety of WovenEndoBridge (WEB)-assisted cerebral aneurysm embolization

PURPOSE

Long-term compaction, compression, migration, and recurrence rates of the WovenEndoBridge devices remain unknown. The purpose of this study was to detect these rates and safety profiles of the WovenEndoBridge within 7 years period.

MATERIALS AND METHODS

Eighty-three aneurysms of 79 patients treated with the WovenEndoBridge device were retrospectively evaluated using an occlusion scale (e.g. complete occlusion, neck remnant, and aneurysm remnant) on angiography images.

RESULTS

The residual aneurysm was observed in 11 (13%) aneurysms. The mean and median diameters of the recurrent aneurysms were 6 and 7 mm. Most of the recurrent aneurysms were complex type and/or ruptured. Mean diameters and the neck-to-body ratios of all residual aneurysms in the preoperative imaging exams were above 4 mm and 0.6, respectively. The median values of preoperative height and neck measurements were higher in the recurrent aneurysms than in the adequate occlusion group (p = 0.006, p = 0.019, respectively). There was a statistically significant positive relationship between preoperative height/neck measurements and the mean diameters of residual aneurysms (rs = 0.32 and p = 0.003; rs = 0.28 and p = 0.011, respectively). The WovenEndoBridge compaction/compression and migration were observed in 5 (45%) and 2 (18%) of the recurrent aneurysms. In 7 (64%) of the residual aneurysms, thrombosed areas were found within the aneurysm. In the follow-up period, four aneurysms (4.8%) were retreated due to widened residual aneurysm. Other aneurysms were improved or stable within 7 years.

DISCUSSION

Our adequate occlusion rate was 87%. Occlusion rates are less favorable than aneurysms with a long height, wide neck, or high neck-to-body ratio. Our study confirms the high safety and efficiency of the WovenEndoBridge. Compaction, compression, and/or migration of the WovenEndoBridge and the presence of intra-aneurysmal thrombosis are the main reasons for the recurrences.

Development of the SAFETEA Scores for Predicting Risks of Complications of Preventive Endovascular or Microneurosurgical Intracranial Aneurysm Occlusion

BACKGROUND AND OBJECTIVES

Preventive unruptured intracranial aneurysm (UIA) occlusion can reduce the risk of subarachnoid hemorrhage, but both endovascular and microneurosurgical treatment carry a risk of serious complications. To improve individualized management decisions, we developed risk scores for complications of endovascular and microneurosurgical treatment based on easily retrievable patient, aneurysm, and treatment characteristics.

METHODS

For this multicenter cohort study, we combined individual patient data from patients with UIA aged 18 years or older undergoing preventive endovascular treatment (standard, balloon-assisted or stent-assisted coiling, Woven EndoBridge-device, or flow-diverting stent) or microneurosurgical clipping at one of the 10 participating centers from 3 continents between 2000 and 2018. The primary outcome was death from any cause or clinical deterioration from neurologic complications ≤30 days. We selected predictors based on previous knowledge about relevant risk factors and predictor performance and studied the association between predictors and complications with logistic regression. We assessed model performance with calibration plots and concordance (c) statistics.

RESULTS

Of the 1,282 included patients, 94 (7.3%) had neurologic symptoms that resolved <30 days, 140 (10.9%) had persisting neurologic symptoms, and 6 died (0.5%). At 30 days, 52 patients (4.1%) were dead or dependent. Predictors of procedural complications were size of aneurysm, aneurysm location, familial subarachnoid hemorrhage, earlier atherosclerotic disease, treatment volume, endovascular modality (for endovascular treatment) or extra aneurysm configuration factors (for microneurosurgical treatment, branching artery from aneurysm neck or unfavorable dome-to-neck ratio), and age (acronym: SAFETEA). For endovascular treatment (n = 752), the c-statistic was 0.72 (95% CI 0.67-0.77) and the absolute complication risk ranged from 3.2% (95% CI 1.6%-14.9%; ≤1 point) to 33.1% (95% CI 25.4%-41.5%; ≥6 points). For microneurosurgical treatment (n = 530), the c-statistic was 0.72 (95% CI 0.67-0.77) and the complication risk ranged from 4.9% (95% CI 1.5%-14.9%; ≤1 point) to 49.9% (95% CI 39.4%-60.6%; ≥6 points).

DISCUSSION

The SAFETEA risk scores for endovascular and microneurosurgical treatment are based on 7 easily retrievable risk factors to predict the absolute risk of procedural complications in patients with UIAs. The scores need external validation before the predicted risks can be properly used to support decision-making in clinical practice.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that SAFETEA scores predict the risk of procedural complications after endovascular and microneurosurgical treatment of unruptured intracranial aneurysms.

Treatment of Wide-Necked Cerebral Aneurysms Using the WEB Device Including Flow Alteration Assessment With Color-Coded Imaging: A Single Center Experience

Objective

The Woven EndoBridge (WEB) device (MicroVention, Tustin, CA) has extended the treatment of cerebral aneurysms. Despite the fact that the WEB device has shown promising clinical results, little is known about the caused intra-aneurysmal flow alterations. Here we present our clinical experience with the WEB, including examining various syngo iFlow (Siemens AG, Erlangen, Germany) parameters to predict aneurysm occlusion.

Methods

We reviewed the data from patients with unruptured cerebral aneurysms treated with a WEB device between 2016 and 2020. Aneurysm occlusion and complications were assessed. Furthermore, different quantitative criteria were evaluated using syngo iFlow after digital subtraction angiography.

Results

A total of 26 patients hosting 26 cerebral aneurysms met the inclusion criteria. Follow-up was available for 21 patients, with a mean of 7.3 ± 6.3 months. A total of 71.4% (n = 15) of the aneurysms included were located in the anterior and 28.6% (n = 6) in the posterior circulation. Adequate aneurysm occlusion was achieved in 85.7% (n = 18). The iFlow parameters for reduced aneurysm outflow (ID-R) differed significantly from the parameters for reduced inflow (PI-R and PI-D) (P < 0.001). The parameters did not differ significantly between adequately and insufficiently occluded aneurysms. Only a trend towards a lower ID-R of insufficiently occluded aneurysms was observed (P = 0.063), indicating a potential predictive value for insufficient aneurysmal outflow. There was no treatment-related morbidity or mortality.

Conclusions

The applied syngo iFlow parameters confirmed that flow changes induced by the WEB device significantly affect outflow compared to inflow and have potential predictive value for adequate aneurysm occlusion.

Simulation of intra-saccular devices for pre-operative device size selection: Method and validation for sizing and porosity simulation

Intra-saccular devices (ID) are novel braided devices used for complex intracranial aneurysms treatment. Treatment success is associated with correct device size selection. A technique that predicts the ID size within the aneurysm before intervention will provide a powerful computational tool to aid the interventionist during device selection. We present a method to calculate the device's final height, radial expansion and porosity within the patient's anatomy, which allows assessing different device sizes before treatment takes place. The proposed sizing technique was tested in-vitro and in real patient's geometries obtained from 3DRA angiographic images of 8 unruptured aneurysms previously treated with IDs. The obtained simulated height was compared to the real height, with a mean error of less than 0.28 mm (±0.44). The porosity calculation method was tested in-vitro with an error of 0.02 (±0.022). The results of both sizing and porosity experiments resemble well measures from real patients. This methodology could be used before treatment to provide the interventionist with additional information that allows selecting the device that best fits the patient's aneurysm to be treated.

Woven EndoBridge in Wide-Neck Bifurcation Aneurysms: Digital Subtraction Angiography at 3-Year Follow-Up

Introduction: The Woven EndoBridge (WEB) device is a self-expanding intrasaccular braided-wire device for the treatment of wide-neck bifurcation aneurysms (WNBAs). Even though this device has an excellent safety profile and a low risk of rebleeding, little is known about its long-term effects. Material and Methods: All patients treated with WEB due to ruptured WNBAs were subjected to follow-up digital subtraction angiography (DSA) at 2 and 3 years after device deployment. The degree of residual neck was assessed through BOSS, Lubicz, and WEBCAST scales. Data on modified Rankin scale (mRS), bleeding events, and ischemic events occurring during this time period were collected as well. Lastly, overall and procedure-related mortality rates were calculated. Results: A total of 21 patients were treated between 1 January 2016, and 31 December 2018. DSA demonstrated a patency grade of 57.1% and 61.1% at 2 and 3 years, respectively. The overall 2-year mortality rate due to causes unrelated to the aneurysm was 14.3%. None of the patients were retreated between the 2- and the 3-year follow-up. No rebleeding or stroke events occurred during the follow-up. Conclusions: WEB-treated ruptured aneurysms showed an excellent degree of stability over time. The overall mortality rate—unrelated to the procedure–observed in our sample was higher than what reported in the literature, a possible bias associated with the COVID-19 pandemic.

Determinants of cerebral aneurysm occlusion after embolization with the WEB device: a single-institution series of 215 cases with angiographic follow-up

Background

Woven EndoBridge (WEB) devices are becoming a reliable option for the treatment of wide-neck bifurcation aneurysms, but clear predictive factors are still missing to understand the one in five aneurysm remnant rate.

Objective

To evaluate occlusion outcomes after WEB treatment to identify potential determinants of aneurysm occlusion.

Methods

A single-center database with consecutive aneurysms treated with WEB between July 2012 and October 2021 was reviewed for potential determinants of aneurysm adequate occlusion (defined as a Bicêtre Occlusion Scale Score (BOSS) of 0, 0’, 1 or 2), through univariate and multivariable analysis. Patients without angiographic follow-up were excluded.

Results

215 of 247 individual aneurysms were included in the final analysis, of which 59 (27%) were ruptured. Mean age of patients was 56 years (range 23–90 years) and 65% were female. Mean angiographic follow-up was at 18 months (range 3–97 months). Adequate and complete occlusion were achieved in 171/215 (79.5%) and 135/215 (62.8%) of cases, respectively. Aneurysm irregular shape (aOR=0.42, 95% CI 0.20 to 0.88; p=0.02), aneurysm height (aOR=0.79, 95% CI 0.66 to 0.94; p<0.01), and WEB shape modification (aOR=0.98, 95% CI 0.97 to 1.00; p=0.02) were all independent predictors of aneurysm recurrence, whereas the WEB oversizing ratio (WEB width/aneurysm mean width) (aOR=16.4, 95% CI 1.4 to 266.7; p=0.04) was an independent predictor of adequate occlusion.

Conclusion

In this study we demonstrated that a width oversizing strategy of the WEB device was an independent predictor of aneurysm angiographic occlusion. Conversely, aneurysm height, irregular aneurysm, and WEB shape modification were all independent determinants of angiographic aneurysm remnant. These results may help to select aneurysms suitable for the WEB device and WEB sizing.

Results of the pToWin Study: Using the pCONUS Device for the Treatment of Wide-Neck Intracranial Aneurysms

Coil embolization has become a well-established option for the treatment of intracranial aneurysms. Yet, wide-neck bifurcation aneurysms (WNBAs) remain a challenge. The pCONUS is the first generation of a stent-like implant for the bridging of WNBAs to enable coiling. The pToWin study was a prospective, single-arm, multicenter study conducted to analyze the safety and efficacy of the pCONUS in the treatment of WNBAs. The primary effectiveness endpoint was the rate of adequate occlusion of the aneurysm at 3–6 and 7–12 months. The primary safety endpoint was the occurrence of major ipsilateral stroke or neurological death during the follow-up. A total of 115 patients were included. Aneurysm locations were the middle cerebral artery in 52 (45.2%), the anterior communicating artery in 35 (30.4%), the basilar artery in 23 (20%), the internal carotid artery terminus in three (2.6%), and the pericallosal artery in two (1.7%) patients. Treatment was successfully performed in all but one patient. The morbi-mortality rate was 1.9% and 2.3% at 3–6 and 7–12 months, respectively. Of the aneurysms, 75.0% and 65.6% showed adequate occlusion at 3–6 and 7–12 months, respectively. pCONUS offers a safe and reasonably effective treatment of WNBAs, demonstrated by acceptable adequate aneurysm occlusion and low rates of adverse neurologic events.

Delayed rebleeding of an Acom aneurysm treated with a web device: Endovascular management

We report a case of cerebral aneurysm rerupture 24 months after initial bleeding and complete occlusion using a WEB device. A middle-aged patient was transferred at our institution because of a recurrent aneurysmal bleeding. The patient was graded WFNS2 and unenhanced CT showed a modified Fisher grade 3 SAH. DSA showed an increased compaction and an evolutive "proximal recess" of the WEB device associated with a small unprotected part of the aneurysm wall and a bleb pointing towards the haemorrhage. Balloon- and stent-assisted coiling was performed, allowing to completely occlude the recurrence. The patient suffered no neurological deficit neither delayed complication and was discharged at day 16.

Intracranial aneurysm treatment with intrasaccular flow disruption: comparison of WEB-21 and WEB-17 systems

BACKGROUND

New generations of Woven EndoBridge (WEB) devices (WEB-21 and WEB-17) are available to treat aneurysms with a width <6.5 mm. Limited comparisons between both systems exist in the literature, but mid-term efficacy has not been compared. Our study aimed to compare the indications, feasibility, and safety of both systems and to evaluate their efficacy at mid-term follow-up (12 months).

METHODS

Aneurysms treated with WEB-21 and WEB-17 were extracted from a prospective database. Patient and aneurysm characteristics, complications, and anatomical results were analyzed by an interventional neuroradiologist, independent of the procedures.

RESULTS

From June 2015 to November 2019, 87 patients with 92 aneurysms were treated with WEB-21 (38/92, 41.3%) and WEB-17 (54/92, 58.7%). WEB-21 and WEB-17 had high treatment feasibility (97.4% and 94.4%, respectively). A higher percentage of ruptured aneurysms were treated with WEB-17 (9.3%) than with WEB-21 (2.6%; p=0.03). Morbidity and mortality at 1 month were similar in both groups (no morbidity in either group, and mortality 2.7% in the WEB-21 group and 2.0% in the WEB-17 group). The rate of complete and adequate aneurysm occlusion was not significantly higher with the WEB-17 system (59.2% and 95.9%, respectively) compared with the WEB-21 (52.9% and 85.3%, respectively).

CONCLUSIONS

This study showed the high feasibility of aneurysm treatment with both the WEB-21 and WEB-17 systems. Indications were relatively similar with both devices except for ruptured aneurysms, which were more frequently treated with the WEB-17 device. Efficacy at 12 months (complete and adequate occlusions) was slightly, but not significantly, better with the WEB-17 device.

Efficacy and safety of flow diverters in posterior circulation aneurysms and comparison with their efficacy in anterior circulation aneurysms: A systematic review and meta-analysis

PURPOSE

We aimed to assess the efficacy and safety of flow-diverter stents (FDs) in the management of posterior circulation cerebral aneurysms and compare FD efficacy between anterior and posterior circulation aneurysms.

METHODS

We searched the PubMed, Scopus, Cochrane, and Web of Science databases for relevant studies through March 2020. Studies assessing FDs for posterior circulation aneurysms that included ≥20 treated aneurysms were included. Moreover, the studies compared FD efficacy between anterior and posterior circulation aneurysms were included. Data regarding angiographic aneurysmal occlusion, procedural complications, mortality, and morbidity were extracted and pooled in a random-effects meta-analysis model.

RESULTS

Fourteen studies with a total of 659 patients and 676 posterior circulation aneurysms were included. The pooled rate of aneurysmal occlusion at long-term angiographic follow-up was 78% [95% confidence interval (CI), 71-85]. The pooled rates of intraparenchymal hemorrhage, ischemia, and procedure-related mortality and neurological morbidity were 2%, 8%, 7%, and 6%, respectively. Complete occlusion occurred in 82.4% of the posterior circulation aneurysm subgroup and 77.5% of the anterior circulation aneurysm subgroup. The difference was not significant (relative risk 1.01; 95% CI, 0.86-1.19; p = 0.91). Regression analysis showed that elderly patients and females had higher morbidity.

CONCLUSION

Posterior circulation aneurysms can be effectively treated with FDs with comparable occlusion rates to those in anterior circulation aneurysms. However, periprocedural complications are not negligible.

The Woven EndoBridge for unruptured intracranial aneurysms: Results in 95 aneurysms from a single center

BACKGROUND AND PURPOSE

The Woven EndoBridge (WEB) is an intrasaccular flowdisruptor that is increasingly used for the treatment of (wide-necked) aneurysms. We present our experience with the WEB for unruptured aneurysms.

MATERIALS AND METHODS

Between April 2014 and August 2019, 93 patients with 95 unruptured aneurysms were primarily treated with the WEB. There were 69 women and 24 men, mean age 61 years (median 58, range 37-80).

RESULTS

Of 95 aneurysms, 86 had been discovered incidentally, 3 were symptomatic and 6 were additional to another ruptured aneurysm. Location was anterior communicating artery 33, middle cerebral artery 29, basilar tip 19, carotid tip 8, posterior communicating artery 4, posterior inferior cerebellar artery 1, superior cerebellar artery 1. Mean aneurysm size was 6 mm (median 6, range 3-13 mm).In one aneurysm additional coils were used and in another, a stent was placed. There was one procedural rupture without clinical sequelae. There were two thrombo-embolic complications leading to permanent deficit in one patient (mRS 2). Morbidity rate was 1.0% (1 of 93, 95%CI 0.01-6.5%) and mortality was 0% (0 of 93, 95%CI 0.0-4.8%). Angiographic follow-up at six months was available in 85 patients with 87 aneurysms (91%). Of 87 aneurysms, 68 (78%) were completely occluded, 14 (16%) had a neck remnant and 5 were incompletely occluded. Four aneurysms were retreated. Retreatment rate was 4.5% (4 of 87, 95%CI 1.7-13.6%).

CONCLUSION

WEB treatment of unruptured aneurysms is safe and effective. Additional devices are needed only rarely and retreatment at follow-up is infrequent.

Woven EndoBridge device for the treatment of ruptured intracranial aneurysms: A systematic review of clinical and angiographic results

BACKGROUND AND OBJECTIVE

The clinical outcome and angiographic outcome data of Woven EndoBridge (WEB) device for the treatment of ruptured intracranial aneurysms (IAs) are limited. We conducted a meta-analysis of the latest literature on the WEB device in the treatment of ruptured IAs.

METHODS

A comprehensive literature search of 4 databases (PubMed, Web of Science, Cochrane library, and Embase) was conducted for studies published from January 1, 2010 to December 31, 2020. Two reviewers independently extracted variables (aneurysm and patient characteristics) using a prespecified data-collection sheet. Outcomes studied included initial and latest follow-up angiographic outcomes, technical success rate, perioperative mortality, retreated rate, perioperative re-bleeding, complication, intraoperative rupture, favorable neurologic outcome at discharge. We used random-effects model to pool the data.

RESULTS

We finally presented the results of 7 articles including 276 patients with 283 aneurysms. Initial complete and adequate occlusion rate were 38% (95% CI, 25%-50%) and 98% (95% CI, 95%-100%), respectively. Latest follow-up complete and adequate occlusion rate were 61% (95% CI, 46%-75%) and 91% (95% CI, 84%-98%), respectively.Technical success rate was 99% (95% CI, 98%-100%). Perioperative mortality rates and perioperative re-bleeding rate were 9% (95% CI, 3%-15%) and 1% (95% CI, 0%-2%), respectively. Retreated rate was 6% (95% CI, 3%-10%). Overall and WEB treatment-related thromboembolic complication was 10% (95% CI, 6%-13%) and 7% (95% CI, 2%-12%), respectively. Intraoperative rupture rate was 3% (95% CI, 0%-6%).

CONCLUSION

Endovascular treatment of ruptured IAs with the WEB device has a good safety profile and an acceptable aneurysm occlusion rate.

Impact of A1 Asymmetry on the Woven EndoBridge Device in Anterior Communicating Artery Aneurysms

BACKGROUND AND PURPOSE

Woven EndoBridge (WEB) devices are increasingly used to treat intracranial aneurysms. A1 asymmetry contributes to anterior communicating artery aneurysm formation and to treatment instability after coiling. We sought to evaluate whether A1 asymmetry had an impact on angiographic outcome in anterior communicating artery aneurysms treated with the WEB.

MATERIALS AND METHODS

Anterior communicating artery aneurysms treated between July 2012 and July 2020 with the WEB from an institutional review board-approved database were reviewed. A1 asymmetry was categorized as the following: absence of the A1 segment on 1 side (unilateral A1) versus bilateral A1. Univariate and multivariable analyses assessed independent predictors of adequate (WEB Occlusion Scale A, B, and C) and complete occlusion (WEB Occlusion Scale A and B).

RESULTS

Forty-eight individual aneurysms (47 patients) were included in the final analysis, of which 16 (33%) were acutely ruptured. The mean size was 6.5 (SD, 2.2) mm. Adequate and complete occlusion was achieved in 33 (69%) and 30 (63%) cases, respectively. Unilateral A1 was associated with significantly higher rates of adequate (92% versus 60% for bilateral A1; P = .03) and complete occlusion (92% versus 50% for bilateral A1; P < .01). Multivariable logistic regression confirmed unilateral A1 as an independent predictor of both adequate (OR = 10.6; 95% CI, 1.6-220.7; P = .04) and complete occlusion (OR = 9.5, 95% CI, 1.5-190.2; P = .04. A sensitivity analysis comparing unilateral "functional" A1 with bilateral "functional" A1 showed similar results. WEB shape modification was not influenced by the unilateral A1 configuration (P = .70).

CONCLUSIONS

Anterior communicating artery aneurysms with a unilateral A1 configuration treated with WEB devices are associated with better angiographic outcome than those with bilateral A1. This finding supports the hypothesis that WEB devices are resistant to unilateral flow in the aneurysm as opposed to coils.

The Woven EndoBridge device for ruptured intracranial aneurysms: international multicenter experience and updated meta-analysis

PURPOSE

The Woven EndoBridge (WEB) can be used to treat wide-necked aneurysms without antiplatelet medications, suggesting it may have advantages in the setting of aneurysmal subarachnoid hemorrhage (aSAH). The goal was assessment of safety and efficacy of WEB in aSAH given the delayed nature of aneurysmal thrombosis.

METHODS

An international retrospective analysis of patients with aSAH treated with WEB was conducted at 7 tertiary centers from 2016 to 2020. Outcomes included rates of rebleeding, retreatment, complications, and complete occlusion. Furthermore, a systematic review and meta-analysis was conducted from 2011 to 2020 assessing the same outcomes. All pooled event rates were calculated using a random effect model.

RESULTS

Consecutive patients with aSAH harbored 25 aneurysms that were treated with 29 WEB devices. The mean age was 53 years, and 65% were female. Zero experienced rebleeding, 2 were retreated, 2 experienced complications, 16 were completely occluded at 3 months, and 21 were completed occluded at 9-12 months. Meta-analysis of 309 WEB treatments for aSAH from 7 case series revealed 2.5% (95% CI 1-5%) had rebleeding, 9% (95% CI 4-17%) were retreated, 17% (95% CI 10-30%) had complications, and 61% (95% CI 51-71%) were completely occluded at 3-6 months.

CONCLUSION

WEB embolization in the setting of aSAH provides similar protection against rebleeding with comparable retreatment rates to traditional approaches. However, there is a higher rate of incomplete radiographic occlusion and operative complications compared to WEB embolization of unruptured aneurysms. Long-term prospective studies are needed to fully delineate the role of WEB embolization in aSAH.

Intrasaccular Flow Disruption with the Woven EndoBridge for Narrow-Necked Aneurysms: A Safety and Feasibility Study

OBJECTIVE

The Woven EndoBridge (WEB) received U.S. Food and Drug Administration approval for endovascular treatment of wide-necked bifurcation aneurysms. We evaluated the feasibility, safety, and efficacy of the WEB for treatment of narrow-necked aneurysms.

METHODS

This multicenter study included 17 narrow-necked aneurysms, defined by a neck width <4 mm and a dome-to-neck ratio >2. Aneurysm characteristics, treatment strategies, technical success, complications, and angiographic outcomes were retrospectively assessed.

RESULTS

Aneurysm locations included the internal carotid artery (7 cases), anterior communicating artery (4 cases), middle cerebral artery (4 cases), and basilar artery (2 cases). The median aneurysm size was 7.4 mm with a median neck width of 2.3 mm. The technical success rate was 100%. There were no neurological complications. Angiographic control revealed complete and adequate occlusion in 13 of 15 (86.7%) and 14 of 15 (93.3%) cases, respectively, after 6 months and in 6 of 7 (85.6%) and 7 of 7 (100%) cases, respectively, after a median of 13 months. Two aneurysms were retreated with flow diverters.

CONCLUSIONS

WEB embolization of narrow-necked aneurysms was technically feasible and safe and might be considered as an alternative treatment option to conventional coiling in selected cases.

Recurrent and Residual Aneurysms After Woven EndoBridge (WEB) Therapy: What's Next?

The prevalence of recurrent and residual aneurysms following Woven EndoBridge (WEB) treatment is not insignificant. The goal of this systematic review was to evaluate retreatment methods for such aneurysms and their outcomes. PubMed, Embase, and Scopus databases were systematically searched, and results were reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Original studies reporting on aneurysms that were retreated after WEB were included. Sixteen studies (n = 901 aneurysms), of which three were prospective, reported on retreated aneurysms following initial WEB treatment. Of those 901 aneurysms, on average 18.7 ± 11.5% were recurrent or residual at the last follow-up and 10.7 ± 11% required some form of retreatment. When compared to WEB-IT (WEB Intra-saccular Therapy) data, retreated aneurysms were more likely to be large in size (p < 0.0001) and more likely to have been initially treated with the WEB dual-layer configuration. The mean age of those with retreated aneurysms was 58 ± 5.7 years old, and the mean size of aneurysm dome was 11.1 ± 5.5 millimeters. Majority (34.1%) of the aneurysms were located at the basilar apex. Retreatment modalities included coiling (20%), stent-assisted coiling (38.7%), additional WEB device (13.3%), flow diversion (16%), and clipping (12%). Majority of retreated cases had favorable outcomes, with 96.4 ± 13.4% of the cases demonstrating technical success and 90.5 ± 18.2% having adequate occlusion at the last follow-up. Our systematic review suggests that retreatment of recurrent and residual aneurysms after initial WEB treatment is feasible. Future prospective studies would be helpful in validating these results.

Endovascular Treatment of Intracranial Aneurysms

Traditionally, surgical clipping was the only available treatment modality for intracranial aneurysms. However, in the last few decades, the endovascular therapy of intracranial aneurysms (IAs) has seen a tremendous evolution and development. From coiling to flow diversion and flow disruptor devices, endovascular treatment modalities have increased in number and received broader indications throughout the years. In this review article, the treatment modalities for the endovascular management of IAs are presented, emphasizing newer devices and technologies.