Safety and Efficacy of Aneurysm Treatment with the WEB: Results of the WEBCAST 2 Study

CLinical EValuation of WEB 17 device in intracranial aneuRysms (CLEVER): 1-year effectiveness results for ruptured and unruptured aneurysms

BACKGROUND

The Woven EndoBridge (WEB) device is designed to treat wide-necked bifurcation aneurysms. The WEB 17 is the latest iteration and can be delivered through a 0.017″ microcatheter. The CLEVER study demonstrated that WEB 17 is safe and effective for providing protection against bleeding or rebleeding at 1 month and 1 year.

OBJECTIVE

To evaluate angiographic stability at 1 year.

METHODS

The CLEVER study was a prospective multicenter study conducted in 17 European centers, involved 163 subjects, comprising 60 ruptured and 103 unruptured aneurysms. Independent assessment of 1-year follow-up imaging was incorporated into the study design.

RESULTS

Aneurysm diameters ranged from 2.0 to 9.2 mm, with 95.7% being broad-based (dome-to-neck ratio <2). Follow-up imaging at 1 year was completed for 146 out of 163 subjects (89.6%) and evaluated by an independent core laboratory. The primary efficacy endpoint of adequate occlusion without re-treatment at 1 year was achieved for 120 (82.2%) of all subjects. At 1 year, the adequate occlusion rate was 86.5% for ruptured aneurysms (73.1% complete occlusion) and 82.4% for unruptured aneurysms (57.1% complete occlusion). The overall re-treatment rate at 1 year was 2.6% (4/152), with 3.1% (3/97) for unruptured aneurysms and 1.8% (1/55) for ruptured aneurysms CONCLUSION: Delivery of the WEB 17 via 0.017 inch catheters represents a significant evolution of the WEB design. The results of CLEVER presented here demonstrate that it maintains the same efficacy as previous generations of WEB.

Contour Neurovascular System for endovascular embolization of cerebral aneurysms: a multicenter cohort study of 10 European neurovascular centers

BACKGROUND

Intrasaccular devices have become increasingly popular in the treatment of cerebral aneurysms, particularly at the bifurcation. Here we evaluate the Contour Neurovascular System, an intrasaccular device for the endovascular treatment of cerebral aneurysms, in a multicenter cohort study, the largest to the best of our knowledge.

METHODS

Consecutive patients with intracranial aneurysms treated with the Contour Neurovascular System between February 2017 and October 2022 at 10 European neurovascular centers were prospectively collected and retrospectively reviewed. Patient and aneurysm characteristics, procedural details, and angiographic and clinical outcomes were evaluated.

RESULTS

During the study period, 279 aneurysms (median age of patients 60 years, IQR 52-68) were treated with Contour. In 83.2% of patients the device was placed electively, whereas the remaining patients were treated in the setting of acute subarachnoid hemorrhage. The most common locations were the middle cerebral artery (26.5%) followed by the anterior communicating region (26.2%). Median aneurysm dome and neck size were 5.2 mm (IQR 4.2-7) and 3.9 mm (IQR 3-5). Contour size 7 (39%) and 9 (25%) were most used. Thromboembolic and hemorrhagic complications occurred in 6.8% and 0.4% of aneurysms, respectively. Raymond-Roy 1 and 2 occlusions at last follow-up were achieved in 63.2% and 28.3%, respectively, resulting in adequate occlusion of 91.5% of aneurysms.

CONCLUSION

This is the largest multicenter study reporting the outcome on the Contour Neurovascular System. At 1 year, the self-evaluated data on safety and efficacy are comparable to data of existing intrasaccular devices. Contour is a promising technology in the treatment of cerebral aneurysms.

Subtemporal Approach for the Treatment of Ruptured and Unruptured Distal Basilar Artery Aneurysms: Is There a Contemporary Use?

BACKGROUND AND OBJECTIVES

Distal basilar artery aneurysms (DBAs) are high-risk lesions for which endovascular treatment is preferred because of their deep location, yet indications for open clipping nonetheless remain. The subtemporal approach allows for early proximal control and direct visualization of critical posterior perforating arteries, especially for posterior-projecting aneurysms. Our objective was to describe our clinical experience with the subtemporal approach for clipping DBAs in the evolving endovascular era.

METHODS

This was a retrospective, single-institution case series of patients with DBAs treated with microsurgery over a 21-year period (2002-2023). Demographic, clinical, and surgical data were collected for analysis.

RESULTS

Twenty-seven patients underwent clipping of 11 ruptured and 16 unruptured DBAs with a subtemporal approach (24 female; mean age 53 years). Ten patients had expanded craniotomies for treatment of additional aneurysms. The aneurysm occlusion rate was 100%. Good neurological outcomes as defined by the modified Rankin Scale score ≤2 and Glasgow Outcome Scale score ≥4 were achieved in 21/27 patients (78%). Two patients died before hospital discharge, one from vasospasm-induced strokes and another from an intraoperative myocardial infarction.

CONCLUSION

These results demonstrate that microsurgical clip ligation of DBAs using the subtemporal approach remains a viable option for complex lesions not amenable to endovascular management.

Modification of Woven Endo-Bridge After Intracranial Aneurysm Treatment: A Methodology for Three-Dimensional Analysis of Shape and Relative Position Changes

During follow-up of patients treated with WEB devices, shape changes have been observed. The quantitative three-dimensional measurement of the WEB shape modification (WSM) would offer useful information to be studied in association with the anatomical results and try to better understand mechanisms implicated in this modification phenomenon. We present a methodology to quantify the morphology and position of the WEB device in relation to the vascular anatomy. Three-dimensional rotational angiography (3DRA) images of seven aneurysms patients treated with WEBs were used, which also accompanied by a post-treatment 3DRA image and a follow-up 3DRA image. The device was manually segmented, obtaining the 3D models after treatment and at the follow-up. Volume, surface area, height, maximum diameter and WSM ratio of both surfaces were calculated. Position changes were evaluated measuring WEB axis and relative position between post-treatment and follow-up. Changes in WEB volume and surface area were observed with a mean modification of - 5.04 % ( ± 14.19 ) and - 1.68 % ( ± 8.29 ) , respectively. The positional variables also showed differences, mean change of device axis direction was 26.25 % ( ± 24.09 ) and mean change of distance l b was 5.87 % ( ± 10.59 ) . Inter-observer and intra-observer variability analyses did not show differences (ANOVA p > 0.05 ). This methodology allows quantifying the morphological and position changes suffered by the WEB device after treatment, offering new information to be studied in relation to the occurrence of WEB shape modification.

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.

Endovascular treatment of intracranial internal carotid artery bifurcation region aneurysms

Intracranial internal carotid artery (ICA) bifurcation region aneurysms are uncommon. When treatment is necessary for ICA, endovascular treatment (EVT) can be a useful option. Due to the complexity of these aneurysms and the variability of EVT techniques, EVT for ICA bifurcation aneurysms is challenging. Currently, it is necessary to perform a review to explore this issue further. In this review, the following issues were discussed: the anatomy of the ICA bifurcation region; the classification, natural history and EVT status of ICA bifurcation region aneurysms; the technique used for identifying ICA bifurcation region aneurysms; and the prognosis and complications of EVT for ICA bifurcation region aneurysms. According to the review and our experience, traditional coiling is currently the preferred therapy for ICA bifurcation region aneurysms. In addition, in select cases, new devices, such as flow diverters and Woven EndoBridge devices, can also be used to treat ICA bifurcation region aneurysms. Generally, EVT is an alternative treatment option for ICA bifurcation region aneurysms.

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.

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.

Woven Endo Bridge shape modification contributes to decrease in adequate occlusion rate after Woven Endo Bridge implantation for wide-neck bifurcation intracranial aneurysms

PURPOSE

Recently, a novel device, the Woven Endo Bridge (WEB), was developed for wide-neck bifurcation intracranial aneurysms (WNBAs). The aim of this study is to investigate factors that contribute to adequate occlusion (AO) after the operation using detailed radiological images.

METHODS

The subjects were 29 patients with 29 aneurysms who received WEB implantation for WNBAs between December 2020 and April 2022. We assessed the contributing factors to AO by retrospectively comparing the AO group and non-AO group.

RESULTS

The mean age was 64.6 ± 13.1 years, and 18 were female (62.1%). The mean aneurysm dome width, aneurysm height, and aneurysm neck diameter were 4.8 ± 0.6 mm, 5.1 ± 0.6 mm, and 3.7 ± 0.6 mm, respectively. After about 6 months, 22 of 29 patients (75.9%) had AO. Complications were observed in 2 patients (6.9%), renal artery injury in one, and minor cerebral infarction in another, but the modified Rankin scale scores of both patients remained unchanged. Multivariate analysis extracted only WEB shape modification (WSM) as a contributing factor to AO (odds ratio: 0.912, p = 0.0287).

CONCLUSION

WEB implantation for WNBAs was a treatment modality with acceptable efficacy and safety. WSM was the only significant factor contributing to non-AO after the treatment. We should clarify the mechanisms or causes of WSM to achieve AO after WEB implantation in future.

A new era in the treatment of wide necked bifurcation aneurysms: Intrasaccular flow disruption

Wide-necked bifurcation aneurysms (WNBAs) are challenging lesions to treat via both open surgical and endovascular techniques. Presently, there are 3 intrasaccular devices available to address many of the limitations of prior techniques, all of which are at different phases of approval for human use around the world. These devices include the Woven EndoBridge (WEB®) made by MicroVention, the Artisse™ Embolization Device made by Medtronic, and the Contour Neurovascular System™ made by Cerus Endovascular. Although heterogenous in design, these devices rely on the principle of using fine mesh overlying the aneurysm neck to slow blood inflow, promoting stagnation and thrombosis that ultimately leads to healing across the neck and exclusion from the circulation. While our understanding improves as long-term occlusion rates from these devices continue to be studied, the safety profiles and short-term success rates demonstrated in recent studies provide optimism for these innovative intrasaccular devices for the treatment of WNBAs. In this paper, we review these 3 intra-saccular flow disruption devices for use in WNBAs and summarize recent literature and studies of their effectiveness and safety.

Microsurgical Clipping of Unruptured Anterior Circulation Aneurysms-A Global Multicenter Investigation of Perioperative Outcomes

BACKGROUND AND OBJECTIVES

Microsurgical aneurysm repair by clipping continues to be highly important despite increasing endovascular treatment options, especially because of inferior occlusion rates. This study aimed to present current global microsurgical treatment practices and to identify risk factors for complications and neurological deterioration after clipping of unruptured anterior circulation aneurysms.

METHODS

Fifteen centers from 4 continents participated in this retrospective cohort study. Consecutive patients who underwent elective microsurgical clipping of untreated unruptured intracranial aneurysm between January 2016 and December 2020 were included. Posterior circulation aneurysms were excluded. Outcome parameters were postsurgical complications and neurological deterioration (defined as decline on the modified Rankin Scale) at discharge and during follow-up. Multivariate regression analyses were performed adjusting for all described patient characteristics.

RESULTS

Among a total of 2192 patients with anterior circulation aneurysm, complete occlusion of the treated aneurysm was achieved in 2089 (95.3%) patients at discharge. The occlusion rate remained stable (94.7%) during follow-up. Regression analysis identified hypertension (P < .02), aneurysm diameter (P < .001), neck diameter (P < .05), calcification (P < .01), and morphology (P = .002) as preexisting risk factors for postsurgical complications and neurological deterioration at discharge. Furthermore, intraoperative aneurysm rupture (odds ratio 2.863 [CI 1.606-5.104]; P < .01) and simultaneous clipping of more than 1 aneurysm (odds ratio 1.738 [CI 1.186-2.545]; P < .01) were shown to be associated with an increased risk of postsurgical complications. Yet, none of the surgical-related parameters had an impact on neurological deterioration. Analyzing volume-outcome relationship revealed comparable complication rates (P = .61) among all 15 participating centers.

CONCLUSION

Our international, multicenter analysis presents current microsurgical treatment practices in patients with anterior circulation aneurysms and identifies preexisting and surgery-related risk factors for postoperative complications and neurological deterioration. These findings may assist in decision-making for the optimal therapeutic regimen of unruptured anterior circulation aneurysms.

Flow-diverter stents combined with flow-T stenting-assisted coiling for the treatment of a large basilar apex aneurysm: a case report with a 9-month follow-up

Background

Endovascular or surgical treatment of wide-neck, large basilar apex aneurysms is challenging. We present a novel concept for the treatment of complex basilar apex aneurysms using flow-diverter devices combined with the flow-T stenting-assisted coiling technique. Assess the efficacy and safety profile of the technique in this complex aneurysm.

Case description

A patient with multiple unruptured intracranial aneurysms underwent staged treatment. A large basilar apex aneurysm was treated with a flow-diverter stent combined with a flow-T stenting-assisted coiling technique in the first stage, and a giant supraclinoid aneurysm was treated with a flow-diverter stent applied in the second stage. Clinical presentations, technical details, intra- and perioperative complications, and clinical and angiographic outcomes were recorded, with a 9-month follow-up.

Results

The patient achieved full neurologic recovery postoperatively. Cerebral angiography performed postoperatively showed revascularization, good laminar flow, and no in-stent or adjacent stenosis.

Conclusion

Flow-diverter stents combined with flow-T stenting-assisted coiling for the treatment of giant basilar apex aneurysms is a feasible technique with efficacy demonstrated at a 9-month follow-up. Staged endovascular treatment of multiple intracranial aneurysms may be a safe and viable option.

Oversizing of the Woven EndoBridge for Treatment of Intracranial Aneurysms Improves Angiographic Results (WEBINAR)

OBJECTIVE

Several studies have demonstrated a high safety and efficacy profile of the Woven EndoBridge (WEB) for endovascular aneurysm treatment. However, contemporary large-scale studies of the WEB are rare. This multicenter study attempts to set a benchmark for state-of-the-art WEB treatment with consistent application of the WEB oversizing technique.

METHODS

This is a retrospective, multicenter study of aneurysms (dome width 2-10 mm) treated with the WEB between 2015 and 2023. Patient and aneurysm characteristics, complications, and clinical and angiographic outcomes were analyzed.

RESULTS

The study consisted of 247 patients treated for 251 aneurysms (25.5% ruptured, 5.6% recurrent). WEB implantation was feasible in 98.8%, achieving a mean WEB/dome ratio of 1.2 ± 0.1. The thromboembolic complication rate was 7.2%, which was higher in ruptured versus unruptured aneurysms (hazard ratio: 2.8, 95%CI: 1.0-7.6, P = 0.04), but lower in cases where WEB 17 was used (hazard ratio: 4.0, 95%CI: 1.4-11.2, P = 0.01). Neurological complications occurred in 8 procedures (3.2%), including 3 (1.2%) major, and 5 (2.0%) minor events. Procedural morbidity and mortality were 0.8% and 0%, respectively. Mid-term complete and adequate occlusion rates were 66.3% and 88.4%, respectively. The retreatment rate was 5.2%. Feasibility, complication, and occlusion rates were comparable between typical and atypical aneurysm locations.

CONCLUSIONS

Oversizing the WEB and using currently available WEB types in this series resulted in slightly better treatment outcomes compared to early WEB studies, confirming the high safety, feasibility, and efficacy of this technique.

Influence of size ratio on retreatment after coil embolization for unruptured bifurcation aneurysms

Background

Aneurysm size is considered a risk factor for aneurysm rupture, and even small aneurysms may rupture, especially bifurcation aneurysms (BAs), which are occasionally detected. Therefore, we aimed to investigate the predictors of retreatment after coil embolization for unruptured BAs, with a particular focus on the absolute and relative size of the aneurysm (size ratio [SR]).

Methods

To evaluate the predictors of retreatment, patients were divided into two groups: those with and those without retreatment. Patient characteristics and radiographic assessments were compared between the groups. SR was defined as the ratio of the maximum aneurysm diameter and the average diameter of the parent artery.

Results

Overall, 181 unruptured BAs in 176 patients were investigated. The mean age of the patients was 63.8 ± 9.6 years. The mean aneurysm size and SR were 7.18 ± 2.94 mm and 2.49 ± 1.32, respectively. Further, 12 aneurysms with retreatment (6.6 %) and 169 aneurysms without retreatment were compared. In univariate analysis, SR was significantly higher in the group with retreatment (P = 0.02), but aneurysm size was not significantly different between the groups (P = 0.09). Multivariable analysis revealed that SR > 2.6 was a significant predictor of retreatment (P = 0.03; odds ratio: 10.41; 95 % confidence interval: 2.1-51.73).

Conclusions

This study showed that SR influences retreatment after coil embolization for unruptured BAs. Therefore, if the aneurysm size and parent artery diameter were small, as in cases with a large SR, meticulous follow-up after coil embolization is required to detect recurrence and recanalization.

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.

Safety and effectiveness of the Woven EndoBridge (WEB) system for the treatment of wide necked bifurcation aneurysms: final 5 year results of the pivotal WEB Intra-saccular Therapy study (WEB-IT)

INTRODUCTION

The US Woven EndoBridge Intra-saccular Therapy (WEB-IT) study is a pivotal, prospective, single arm, investigational device exemption study to evaluate the safety and effectiveness of the WEB device for the treatment of wide neck bifurcation aneurysms (WNBAs). We present complete 5 year data for the cohort of 150 patients.

METHODS

150 patients with WNBAs were enrolled at 21 US and six international centers. Imaging from the index procedure, 6 month, 1 year, 3 year, and 5 year follow-up were reviewed by a core laboratory. Adverse events were reviewed and adjudicated by a clinical events adjudicator.

RESULTS

83 patients had 5 year follow-up imaging and 123 had clinical follow-up. No ruptured (0/9) or unruptured aneurysm (0/141) rebled or bled during follow-up. No new device or procedure related adverse events or serious adverse events were reported after 1 year. At 5 years, using the LOCF method, complete occlusion was observed in 58.1% and adequate occlusion in 87.2% of patients. For patients with both 1 year and 5 year occlusion statuses available, 76.8% (63/82) of aneurysms remained stable or improved with no retreatment. After 1 year, 18 aneurysms were retreated, 11 of which were adequately occluded at 1 year, and 15 of which were retreated in the absence of any deterioration in occlusion grade.

CONCLUSIONS

Five year follow-up data from the WEB-IT study demonstrated that the WEB device was safe and effective when used in the treatment of WNBAs. Aneurysm occlusion rates achieved at 1 year follow-up were durable, with rates of progressive thrombosis far exceeding rates of recurrence over time.

Endovascular treatment of middle cerebral artery aneurysms: current status and future prospects

Middle cerebral artery (MCA) aneurysms are complex and widely distributed throughout the course of the MCA. Various types of aneurysms can occur in the MCA. Ruptured as well as unruptured MCA aneurysms may require treatment to avoid bleeding or rebleeding. Currently, clipping is regarded as the first-line choice for the treatment of MCA aneurysms. However, endovascular treatment (EVT) is emerging as an alternative treatment in selected cases. EVT techniques vary. Therefore, it is necessary to review EVT for MCA aneurysms. In this review, the following issues were discussed: MCA anatomy and anomalies, classifications of MCA aneurysms, the natural history of MCA aneurysms, EVT status and principle, deployments of traditional coiling techniques and flow diverters (FDs), and deployments and prospects of intrasaccular flow disruptors and stent-like devices. According to the review and our experience, traditional coiling EVT is still the preferred therapy for most MCA aneurysms. FD deployment can be used in selective MCA aneurysms. Parent artery occlusion (PAO) can be used to treat distal MCA aneurysms. In addition, new devices can be used to treat MCA aneurysms, such as intrasaccular flow disruptors and stent-like devices. In general, EVT is gaining popularity as an alternative treatment option; however, there is still a lack of evidence regarding EVT, and longer-term data are not currently available for most EVT devices.

Comparative analysis of long term effectiveness of Neuroform Atlas stent versus low profile visualized intraluminal stent/Woven EndoBridge devices in treatment of wide necked intracranial aneurysms

BACKGROUND

We compared the outcomes of wide necked aneurysms (WNA) treated with the Neuroform Atlas with those treated with the low profile visualized intraluminal stent (LVIS) or the Woven EndoBridge (WEB).

METHODS

Objective, prospectively collected, core laboratory adjudicated data from published trials for the Neuroform Atlas, LVIS, and WEB devices were reviewed. ATLAS (Safety and Effectiveness of the Treatment of Wide Neck, Saccular Intracranial Aneurysms With the Neuroform Atlas Stent System) study patients were included if they met other studies' inclusion criteria. Outcomes included (1) primary effectiveness (complete aneurysmal occlusion without retreatment/>50% parent vessel stenosis), (2) primary safety, (3) complete aneurysmal occlusion, and (4) retreatment rates (outcomes evaluated at the 12 month follow-up). Matching adjusted indirect comparison analysis was used to compare outcomes.

RESULTS

Analytical samples included 141 ATLAS subjects meeting WEB-IT (Woven EndoBridge Intrasaccular Therapy Study) criteria (ATLAS/WEB-IT) and 241 meeting LVIS (Pivotal Study of the Low Profile Visualized Intraluminal Support) criteria (ATLAS/LVIS). ATLAS/WEB-IT exhibited significantly higher rates of primary effectiveness and complete occlusion versus WEB (86.6% vs 53.9 %, P<0.0001, and 90.3% vs 53.9%, P<0.0001, respectively). For LVIS, there was no significant differences in primary effectiveness rates between ATLAS and LVIS (84.2% vs 77.7%, respectively, P=0.12). However, ATLAS/LVIS had a significantly higher proportion of patients achieving complete occlusion than LVIS (88.1 vs 79.1, P=0.03). Retreatment rates and primary safety outcomes were not significantly different (P>0.05) for the Atlas versus other devices except for a lower retreatment rate for ATLAS/WEB-IT versus WEB-IT (2.4% vs 9.8%, P=0.01).

CONCLUSION

The Neuroform Atlas provided higher occlusion rates and similar retreatment rates in comparable datasets compared with LVIS and WEB devices when treating WNA.

Endosaccular flow disruption with the Contour Neurovascular System: angiographic and clinical results in a single-center study of 60 unruptured intracranial aneurysms

BACKGROUND

The Contour Neurovascular System is a novel device designed to treat intracranial aneurysms by intrasaccular flow disruption. We report our experience and mid-term follow-up in a series of patients treated with the Contour.

METHODS

The patients were divided into an intention to treat and a per protocol population, the latter defined by the successful implantation of the Contour device. The intention to treat population included 53 patients (30 women, mean age 56 years) with 60 unruptured intracranial aneurysms (53 in the anterior circulation and seven in the posterior circulation). There was clinical and angiographic follow-up immediate postoperatively and at 24 hours, 3 months and 1 year using the Raymond-Roy classification and the O'Kelly-Marotta grading scale.

RESULTS

The Contour was successfully implanted in 54/60 (90%) aneurysms. With regard to the angiographic follow-up, there was adequate occlusion (defined as complete occlusion or presence of a neck remnant) in 31.5% of 54 aneurysms immediately postoperatively, 62.3% (in 53/54 aneurysms) at 24 hours, 81.4% (in 43/54 aneurysms) at 3 months, and 89.3% (in 28/54 aneurysms) at 1 year. Technical complications in 60 aneurysms of the intention to treat population included two (3.3%) inadvertent detachments of the device. Thromboembolic events were observed in four of the 60 aneurysms (6.7%), with no clinical symptoms in three patients and transient morbidity in one (1.7%). No aneurysm bleeding was observed and no patient was retreated during the 1-year follow-up period. There was no permanent morbidity or mortality.

CONCLUSIONS

The Contour device is effective and safe in the treatment of intracranial aneurysms. However, more experience and long-term follow-up are needed.

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.

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.

A systematic review of the Woven EndoBridge device-do findings in pre-clinical animal models compare to clinical results?

BACKGROUND

The Woven Endobridge (WEB) is designed to treat intracranial wide-neck bifurcation aneurysms, preventing subarachnoid hemorrhage. The translational value of animal models used for WEB device testing is unknown. With this systematic review, we aim to identify the existing animal models used in testing the WEB device and compare the efficacy and safety outcomes to those of prospective clinical studies.

METHODS

This study was funded by ZonMw: project number 114024133. A comprehensive search was performed in PubMed and in EMBASE via the Ovid interface. The following exclusion criteria were used: 1) not an original full-length research paper, 2) not an in vivo animal study or a human study, 3) no WEB implantation, 4) if in humans: not a prospective study. The SYRCLE risk of bias tool (animal studies) and the Newcastle-Ottawa quality assessment scale for cohort studies (clinical studies) were used to assess risks of bias. A narrative synthesis was performed.

RESULTS

Six animal studies and 17 clinical studies met the inclusion criteria. The rabbit elastase aneurysm model was the only animal model used to assess WEB device performance. Safety outcomes were never reported in animal studies. Efficacy outcomes were more heterogeneous in animal studies than in clinical studies, which could be due to limited external validity of the animal models in terms of aneurysm induction and dimensions. Both animal and clinical studies were predominantly single-arm studies, and were at unclear risk of several types of bias.

CONCLUSIONS

The rabbit elastase aneurysm model was the only pre-clinical animal model used to assess WEB device performance. Safety outcomes were not evaluated in animal studies and could therefore not be compared to clinical outcomes. Efficacy outcomes were more heterogeneous in animal studies than in clinical studies. Future research should focus on improving methodology and reporting in order to draw accurate conclusions on the performance of the WEB device.

Impact of aneurysm diameter, angulation, and device sizing on complete occlusion rates using the woven endobridge (WEB) device: Single center United States experience

BACKGROUND

The Woven EndoBridge device is a novel treatment option for wide-necked bifurcation intracranial aneurysms (WNBA). While this device has had good results, there remains a subset of WNBA that fail this treatment. The main objective of this study is to identify risk factors that are associated with incomplete occlusion of WEB treated aneurysms at short-term follow up.

METHODS

This was a retrospective study of 31 patients with intracranial aneurysms who were treated with WEB at a single institution in the USA in 2019-2021. Data was collected via chart review on patient demographics, aneurysm characteristics, procedural details, and occlusion status at six months follow up. Bivariate analyses were performed comparing completely occluded aneurysms with neck remnants and residual aneurysms.

RESULTS

16 (52%) had completely occluded aneurysms while 11 (35%) patients had a neck remnant, and 4 (13%) patients had a residual aneurysm at follow up. Patients with neck remnants and residual aneurysms had aneurysms with a larger diameter. A large aneurysm diameter is an independent risk factor for incomplete occlusion (OR 4.23 95% CI 1.08-16.53 P value = 0.038). Patients with residual aneurysms had an average difference between the aneurysm width and WEB diameter of -0.08mm compared to 1.2 mm in patients with occluded aneurysms. 75% of patients with a residual aneurysm presented with a ruptured aneurysm. Lastly, more patients with a residual aneurysm had an immediate angiographic outcome of incomplete occlusion.

CONCLUSION

Larger aneurysms are at risk for incomplete occlusion status post WEB treatment. Larger, ruptured aneurysms with minimal difference in aneurysm and WEB diameter that fail to occlude immediately post-treatment are more likely to present as residual aneurysms at short-term follow up.

Aneurysm Treatment with Woven EndoBridge-17: Angiographic and Clinical Results at 12 Months from a Retrospective, 2-Center Series

BACKGROUND AND PURPOSE

This retrospective, 2-center study investigated the feasibility, safety, and efficacy at 12-month follow-up of the treatment of ruptured, unruptured, and recurrent intracranial aneurysms using the latest generation of the Woven EndoBridge (WEB) device, the WEB-17 system.

MATERIALS AND METHODS

Aneurysms treated with WEB-17 were extracted from the databases of 2 neurovascular centers. Patients, aneurysm characteristics, complications, and clinical and anatomic results were analyzed.

RESULTS

From February 2017 to May 2021, two hundred twelve patients with 233 aneurysms (181/233, 77.7%, unruptured-recurrent, and 52/233, 22.3%, ruptured) were included. High treatment feasibility (95.3%) was reported and was similar in ruptured aneurysms (94.2%) and unruptured-recurrent aneurysms (95.6%) (P = .71) and in typical (95.4%) and atypical (94.7%) locations (P = .70), but it was lower in aneurysms with an angle between the parent artery and main aneurysm axis of ≥45° (90.2%) compared with those with an angle of <45° (97.1%) (P = .03). Global mortality and morbidity were 1.9% and 3.8% at 1 month, respectively, and 4.4% and 1.9% at 12 months, respectively. One-month morbidity (P = .02) and mortality (P = .003) were higher in the ruptured group (10.0% and 8.0%, respectively) compared with unruptured-recurrent group (1.9% and 0.0%, respectively). Overall adequate occlusion (complete occlusion and neck remnant) was 86.3%. The percentage of adequate occlusion was higher (P = .05) in the unruptured-recurrent group (88.5%) compared with the ruptured group (77.5%).

CONCLUSIONS

The WEB-17 system showed high feasibility for ruptured and unruptured aneurysms, typical and atypical locations, and some aneurysms with an angle of ≥45°. As the most recent generation device, the WEB-17 also demonstrates high safety and good efficacy.

Endovascular Treatment Strategies for Aneurysms of the Origin of the Posterior Inferior Cerebellar Artery

BACKGROUND

Treatment of aneurysms at the origin of the posterior inferior cerebellar artery (PICA) is challenging. Surgery is difficult due to the deep location and proximity to cranial nerves and endovascular treatment is complicated due to the often tortuous anatomy of the PICA and its small diameter. The purpose of this study is to report our experience with the endovascular treatment of aneurysms at the origin of the PICA.

METHODS

Consecutive patients with aneurysms at the origin of the PICA who were endovascularly treated at our department were identified from our registry of neuro-angiographies. Clinical, angiographic, and treatment data were analyzed. Endpoints included successful occlusion and recurrence.

RESULTS

Twenty-nine patients were included. 79.3% of the aneurysms were wide-neck with a dome-to-neck ratio <2.65.5% of all endovascular procedures were performed by coiling alone. The procedural rupture rate was 18.75% for endovascularly treated aneurysms presenting with subarachnoid hemorrhage (SAH). Successful embolization was achieved non-significantly more often in the coiling-only group (94.7% vs. 70%, P = 0.066). Aneurysm recurrence after successful occlusion was observed in one case.

CONCLUSIONS

Though aneurysm and parent vessel characteristics were challenging successful occlusion was achieved in a high rate of treatments, often with standalone coiling. Adjunctive techniques like retrograde stenting seem promising to further enhance endovascular results. Interestingly aneurysms arising solely from the origin of the PICA without the V4-segment involved presented with SAH significantly more often and wide-neck aneurysms presenting with SAH had a significantly higher periinterventional rupture rate.

Contour device implantation versus coil embolization for treatment of narrow neck intracranial aneurysms

The novel Contour device is an intrasaccular flow disruption device designed for treatment of intracranial wide-neck bifurcation aneurysms. Outside its original purpose, Contour implantation can be used to treat aneurysms with a higher dome-to-neck ratio which would be suitable for conventional unassisted coil embolization. We compared both techniques in a retrospective single-center analysis. A total of 42 aneurysms from 42 patients with a dome-to-neck ratio of 1.6 or higher were included in this study. Data on technical success, implantation times, radiation dosages, procedural complications, reinterventions and recurrences were gathered and compared. Technical success was achieved in all cases with both techniques. Aneurysm embolization was achieved significantly faster in the Contour group compared to coiling (Overall p = 0.0002; r = 0.580; acute setting: p = 0.005, r = 0.531; elective setting: p = 0.002, r = 0.607). Significantly less radiation dosage was applied in the Contour group (Overall p = 0.002; r = 0.478; acute group p = 0.006; r = 0.552; elective group p = 0.045; r = 0.397). The number of complications was higher in the coiling group compared to the Contour group (Coiling 7/21 (33,3%); Contour 3/21 (14.3%). There was a higher rate of reinterventions in the coiling group (7.6% vs 21.4%). Outside its original intention, the Contour device seems to be a safe and fast alternative to coil embolization for the treatment of narrow-neck-aneurysms.

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.

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.

pCONUS 2 and pCONUS 2-HPC in the treatment of wide-necked intracranial aneurysms: Multicentre UK experience

BACKGROUND/PURPOSE

pCONUS 2 and pCONUS 2-HPC are neck-bridging devices that provide coiling support in the endovascular treatment of wide-necked intracranial aneurysms. To date, limited multicentre data has been published. This study provides the first pooled data from multiple UK centres regarding outcomes for these devices covering the periprocedural period to 6-month follow-up.

MATERIALS/METHODS

This retrospective, single-arm study assessed 65 patients treated over 3 years from the time of procedure to 6 months post-procedure across four UK centres. Data collected included patient demographics, aneurysm characteristics and antiplatelet regimens. Outcome measures were angiographic results and procedure-related complications from the immediate periprocedural period to 6-month follow-up.

RESULTS

Fifty-four unruptured (83.1%) and 11 ruptured (16.9%) aneurysms were treated. Fifty-five aneurysms were located in the anterior circulation (87.7%). There were four device-related intraprocedural complications: three cases of asymptomatic, temporary thrombus formation and one mortality associated with branch vessel occlusion and aneurysm re-bleeding in a ruptured case. There were no post-procedural device-related complications. Satisfactory occlusion was achieved in 58/65 procedures (89.2%) at time of treatment and in 44/60 (73.3%) at 6 months. Satisfactory occlusion correlated with aneurysm size and coiling packing density. Retreatment was required for five unruptured cases (7.7%) and was straightforward with the device in situ.

CONCLUSION

pCONUS 2 and pCONUS 2-HPC have good short-term safety profiles. The use of pCONUS 2-HPC in the acute treatment of ruptured aneurysms with postprocedural SAPT is feasible. The devices have an intraprocedural complication rate of 4/65 (6.2%) across multiple UK centres, including a single death (1.5%).

Assessment of balloon remodeling techniques in endovascular treatment of wide-neck intracranial aneurysms (WN-IAs)

OBJECTIVES

To evaluate the clinical, technical, and angiographic results in endovascular management of wide-neck intracranial aneurysms (WN-IAs) using the balloon-remodeling technique.

METHODS

This study was a prospective, single-center study that was carried out over a period of three years from January 2019 to December 2021 at the Neuro-Interventional Unit at our hospital. Patients who presented with WNIAs and were eligible for endovascular treatment using the balloon-remodeling approach were included in the study.

RESULTS

We included 37 patients with a mean age of 49.7 ± 12.3 years. About 91.9% of the participants had SAH, 5.4% had unruptured aneurysms, and 2.7% had intracranial hemorrhage. The mean time to treatment was 6.97 ± 7.35 days, the mean aneurysm diameter was 5.7 ± 1.7 mm, and the mean neck diameter was 3.8 ± 1.0 mm. The majority of the patients had a dom-to-neck ratio of less than 2 (89.2%). We have used hyper form balloons in 48.6%, hyper glide in 43.2%, Copernic balloons in 5.4%, and eclipse in 2.7%. According to the Raymond-Roy occlusion classification, 86.5% of the patients had complete obliteration, 10.8% had residual neck, and 2.7% had a residual aneurysm. Almost 91.9% had no complications, 2.7% had ischemia, and 5.4% had mild rupture by wire, treated by 5 min hyperinflation of the balloon till hemorrhage stopped.

CONCLUSIONS

Balloon-assisted detachable coiling is an important option in the treatment of WN-IAs. We found that this technique allowed safe and efficient treatment of aneurysms when conventional treatment had failed due to WN. Endovascular coiling using the balloon remodeling technique of wide neck showed a high technical success rate and good short-term clinical outcomes. A good selection of patients with WN-IAs treated by endovascular coiling using balloon remodeling technique and a good selection of materials used help in decreasing the complications.

Photosensitive Hydrogel-Based Embolic Agent Treatment of Wide-Necked Aneurysms: Preliminary Animal Results

Background: The endovascular treatment of cerebral aneurysms has become widespread but may still be limited by recurrence rates or complications. The discovery of novel embolic strategies may help mitigate these concerns. Methods: We formulated a Photosensitive Hydrogel Polymer (PHP) embolic agent which is low-viscosity, shear-thinning, and radio-opaque. After the filling of an aneurysm with PHP with balloon assistance, we utilized photopolymerization to induce solidification. Different methods of light delivery for photopolymerization were assessed in silicone models of aneurysms and in four acute animal trials with venous anastomosis aneurysms in pigs. Then, balloon-assisted embolization with PHP and photopolymerization was performed in three aneurysms in pigs with a one-month follow-up. Filling volume, recurrence rates, and complications were recorded. Results: The PHP was found to be suitable for the intravascular delivery and treatment of cerebral aneurysms. It was found that light delivery through the balloon catheter, as opposed to light delivery through the injection microcatheter, led to higher rates of filling in the 3D model and acute animal model for cerebral aneurysms. Using the balloon-assisted embolization and light delivery strategy, three wide-necked aneurysms were treated without complication. One-month follow-up showed no recurrence or neck remnants. Conclusions: We demonstrated a novel method of balloon-assisted photosensitive hydrogel polymer embolization and photopolymerization, leading to complete aneurysm filling with no recurrence at 1 month in three wide-necked aneurysms in pigs. This promising methodology will be investigated further with longer-term comparative animal trials.

The safety and effectiveness of the Contour Neurovascular System for the treatment of wide-necked aneurysms: A systematic review and meta-analysis of early experience

BACKGROUND

The Contour is a new generation intrasaccular flow disruption tool that aims to cover the aneurysm neck and is sized according to the neck diameter. While several case series have been published, no literature review has been performed on this promising device.

OBJECTIVE

To assess the safety and effectiveness profile of the Contour Neurovascular System for wide-necked aneurysms.

METHODS

We followed the recommendations of the PRISMA checklist Four databases were searched with a supplemental manual search. All data were analyzed using R software version 4.2.1.

RESULTS

We finally included six studies with 131 treated aneurysms. The overall procedural time was 97.27 (95% CI = 70.07-124.47) minutes, ranging from 78.9 to 136.0 min. The pooled adequate occlusion rate was 84.21% (95% CI = 75.45-90.25), and the overall functional independence rate was 94.74% (87.97-97.79). The overall adverse event rate was 4.70 (95% CI = 3.24-6.76), varying among different events from 0.78 to 8.53%. Thromboembolic events were the most commonly encountered in 8.53% of the patients (95% CI = 4.78-14.74), followed by headache and minor stroke with incidence rates of 5.88 (95% CI = 2.83-11.83) and 4.35 (95% CI = 1.41-12.63), respectively. The overall procedural time in studies using the Contour system only was 86.17 (95% CI = 68.70-10.64) minutes, while it was 136 (95% CI = 90.96-181.04) in the Contour-assisted coiling procedures. However, both techniques were comparable regarding adequate occlusion rates and functional independence.

CONCLUSION

With the anticipation of future studies, the Contour Neurovascular System is a safe and effective treatment option for wide-necked intracranial aneurysms.

Flow Diverter Devices in the Treatment of Anterior Communicating Artery Region Aneurysms: Would the Regional Anatomy and the Aneurysm Location Affect the Outcomes?

BACKGROUND

In this study, the authors evaluated the efficacy and the safety of flow diverter devices (FDD) in anterior communicating artery (ACoA) region aneurysms, focusing on anatomical factors that could affect the outcome, such as the location of the aneurysm along the ACoA (centered on ACoA or decentered on the A1-A2 junction) and the anatomy of the ACoA region.

METHODS

Clinical, procedural and follow-up data were analyzed. Aneurysms were classified according to the location along the ACoA (centered or decentered on the A1-A2 junction) and on the basis of the anatomical configuration of the ACoA region. Safety was assessed by recording intraprocedural, periprocedural and delayed complications to determine the morbidity and mortality rates. The functional outcome was evaluated with the modified Rankin scale (mRS) prior to and after the endovascular procedure. To assess the efficacy, midterm and long-term clinical, angiographic and cross-sectional imaging follow-ups were recorded. Subgroup analysis according to the different ACoA regional anatomical configurations and the ACoA aneurysm locations were performed.

RESULTS

33 patients (17 males; 16 females) with ACoA region aneurysms were treated with FDDs. 27 aneurysms were located at the A1-A2 junction (82%) while the remaining six aneurysms were centered on the ACoA. No mortality was recorded. The overall morbidity rate was 6% (2/33 procedures). Major complications occurred in 33% (2/6) of ACoA aneurysms and in the 0% of A1-A2 junction aneurysms. Mid-term and long-term neuroimaging follow-ups showed the occlusion of the aneurysm in 28/33 cases (85%). Complete occlusion rates were 93% in the A1-A2 junction aneurysms and 50% in ACoA aneurysms.

CONCLUSIONS

The FDD is a safe and effective tool that can be used in the treatment of selected cases of ACoA region aneurysms. The location of the aneurysm along the ACoA and the regional anatomy of the ACoA complex could affect the efficacy and safety.

Management of WEB device migration and mal-position in endovascular treatment of cerebral aneurysms

With increasing advances in technology, the breadth of aneurysms that are treatable via an endovascular approach has increased. Wide necked aneurysms remain difficult to treat but the emergence of dedicated intrasaccular flow disruption devices such as the Woven EndoBridge (WEB, Micorvention) has increasingly seen previously ruptured and unruptured wide necked aneurysms successfully embolised and secured from the circulation using a single device.We are reporting two cases of WEB device treatment from the earliest experience with this device at our institution. These were complicated by partial extrusion in one case and remote migration of the WEB device in another case. Our initial cases highlight the importance of case selection and the need for accurate WEB sizing which are paramount to ensure complete occlusion of the aneurysm without complications of dislocation or extrusion into the parent vessel. Since then, we have performed over 170 cases with the WEB device. We also present a comprehensive review of the limited literature available on the management of mal-positioned and dislocated WEB devices. This allows us to reflect on how to avoid these complications and the different management options at the disposal of the neuro-interventionalist once such a complication has already occured. Rescue devices and manoeuvres that we reflect on include microcatheter manipulation, alligator retrieval device, stent retrievers, microsnares, aspiration, and stenting. Ultimately, each case needs to be individually evaluated and the best strategy selected depends on the context and specific circumstances.

Intrasaccular Flow Disruptor-Assisted Coiling of Intracranial Aneurysms Using the Novel Contour Neurovascular Systems and NEQSTENT: A Single-Center Safety and Feasibility Study

Background: Intrasaccular flow disruptors (IFD) have been introduced in the treatment of intracranial aneurysms (IAs) to overcome the low aneurysm occlusion rate and the high recanalization rate of the coiling technique. Among them, the Contour Neurovascular System (CNS) and the Neqstent (NQS) were designed to reconstruct the aneurysmal neck and both can be used as assisting coiling devices. We aimed to report our preliminary experience with the flow disruptor-assisted coiling (IFD-AC) technique. Methods: We performed a retrospective analysis of prospectively collected data of all patients with IAs treated with the IFD-AC. Results: Between February 2021 and April 2022, we treated 15 IAs with the IFD-AC: 10 ruptured and 5 unruptured. The IFD-AC was successfully performed in 13 cases, with a post-operative RROC 1 in 12 cases (92.3%) and RROC 2 in 1 case (7.7%). There was one ischemic event (6.7%) and no hemorrhagic complications. Twelve patients underwent a mid-term radiologic follow-up: Ten IAs (83.4%) presented an adequate occlusion, while 2 (16.7%) had a recurrence. Conclusions: The IFD-AC, both with the CNS and the NQS, seems a safe technique with promising efficacy profile. The IFD-AC has proved to be safe without antiplatelet therapy in ruptured cases. Further studies are needed to confirm our preliminary results.

CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS): 12-month angiographic results of a multicenter study

BACKGROUND

The CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS) study has shown that the endovascular treatment of ruptured bifurcation aneurysms with the Woven EndoBridge (WEB) is safe and effective and provides protection against rebleeding at 1 month and 1 year. The 12-month angiographic follow-up is an important endpoint of the study.

METHODS

The CLARYS study is a prospective multicenter study conducted in 13 European centers. The study enrolled 60 patients with 60 ruptured aneurysms of the anterior and posterior circulation. The study was conducted with an independent assessment of safety outcomes and imaging.

RESULTS

Sixty patients with 60 ruptured bifurcation aneurysms to be treated with the WEB were included. Fifty-three aneurysms (88.3%) had a broad base with a dome to neck ratio <2 (mean 1.6). Of these, 46 patients were evaluated by an independent core laboratory with follow-up imaging performed at 12 months or before eventual retreatment. At 1 year, 19/46 aneurysms (41.3%) were completely occluded (Raymond-Roy grade I), 21/46 (45.7%) had a residual neck and 6/46 (13.0%) had residual aneurysm filling. Adequate occlusion was reported in 40/46 (87%) aneurysms. Six patients underwent target aneurysm retreatment.

CONCLUSIONS

The CLARYS study has previously shown that the use of the WEB in the endovascular treatment of ruptured bifurcation aneurysms provides effective protection against rebleeding with a good safety profile. The angiographic occlusion rates at 1 year reported here are comparable to those already seen in previous multicenter studies which primarily included unruptured aneurysms.

Aneurysm treatment with the Woven EndoBridge (WEB) device in the combined population of two prospective, multicenter series: 5-year follow-up

BACKGROUND

Evaluating a new endovascular treatment for intracranial aneurysms must not only demonstrate short-term safety and efficacy, but also evaluate longer-term outcomes (eg, delayed complications, anatomical results, retreatment). The current analysis reports the 5-year clinical and anatomical results of Woven EndoBridge (WEB) treatment in two European combined trial populations (WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm Therapy) and WEBCAST-2).

METHODS

All adverse events occurring between the procedure and 5-year follow-up were independently evaluated by an expert. Aneurysm occlusion was evaluated by an independent core laboratory using a three-grade scale: complete occlusion, neck remnant, and aneurysm remnant. In cases where data were not available at 5-year follow-up, the last observation carry forward (LOCF) method was used.

RESULTS

The safety and efficacy populations comprised 100 patients and 95 aneurysms, respectively. No adverse event related to the device occurred after the procedure during the 5-year follow-up period. Mortality at 5 years was 7.0% (7/100 patients) including mortality related to the WEB (0/100, 0.0%), the procedure (1/100, 1.0%), and another condition (6/100, 6.0%). At 5 years, complete aneurysm occlusion was observed in 49/95 (51.6%) aneurysms, neck remnant in 25/95 (26.3%), and aneurysm remnant in 21/95 (22.1%). Retreatment rate at 5 years was 11.6% (11/95 aneurysms).

CONCLUSIONS

This analysis conducted in a population of patients with wide-neck bifurcation aneurysms confirms WEB's safety profile. Additional evidence demonstrates good stability of aneurysm occlusion with adequate occlusion (complete occlusion or neck remnant) at 5 years in 77.9% of aneurysms with a low retreatment rate (11.6%).

CLINICAL TRIAL REGISTRATION

WEBCAST and WEBCAST-2: Unique identifier: NCT01778322.

Long-term clinical and angiographic outcome of the Woven EndoBridge (WEB) for endovascular treatment of intracranial aneurysms

The Woven EndoBridge (WEB) is a well-established device for endovascular treatment of wide-necked bifurcation aneurysms. The objective was to evaluate the long-term angiographic outcome of the WEB and to identify factors that influence aneurysm occlusion. Patient, aneurysm and procedural characteristics of 213 consecutive patients treated with the WEB at three German tertiary care centers between 2011 and 2020 were retrospectively reviewed. Aneurysm occlusion was determined immediately after the procedure, at mid-term (≤ 12 months) and at long-term (> 12 months) follow-up. Among 182 included aneurysms (mean diameter: 7.0 ± 2.4, mean neck width: 4.3 ± 1.6 mm), 29.7% were ruptured. The novel WEB 17 was used in 41.8%, and 11.0% were treated in combination with coiling and/or stenting. Complete and adequate occlusions were observed in 101/155 (65.2%) and 133/155 (85.8%) at mid-term, respectively, and in 59/94 (62.8%) and 87/94 (92.6%) at long-term follow-up (median: 19 months), respectively. Among 92 patients available for both mid- and long-term follow-up, occlusion was stable in 72.8%, improved in 16.3% and worsened in 10.9%. There were no major recurrences leading to aneurysm remnants between mid- and long-term follow-up. Retreatment was performed in 10/155 (6.5%) during mid-term and in 1/94 (1.0%) during long-term follow-up. The WEB provides durable aneurysm occlusion at the long-term. Nevertheless, follow-up imaging is necessary to identify late recurrences that may occur in around 10%.

Delayed rupture of an anterior communicating artery aneurysm after elective Woven EndoBridge embolization, re-treated with microsurgical clipping: operative technique and systematic review

BACKGROUND

The Woven EndoBridge (WEB) device is designed for intrasaccular flow disruption for embolization of intracranial aneurysms. In limited experience so far, the rate of rupture after adequate occlusion by embolization is low.

TECHNICAL REPORT

A 58-year-old man initially had an incidental, unruptured 10.4 mm anterior communicating artery (ACoA) aneurysm treated with WEB embolization. Although his 6-month follow-up angiogram showed adequate occlusion of the aneurysm, he presented to our facility with aneurysmal recurrence due to WEB compaction and rupture. This was treated with surgical clipping of the aneurysm.

METHODS

The literature was systematically reviewed for cases of delayed rupture after WEB embolization. Statistical analyses included studies with at least 20 patients and follow-up of 3 months.

RESULTS

We identified 36 studies, which were primarily retrospective observational studies. The rate of complete occlusion ranged from 33% to 89%, and the rate of re-treatment ranged from 1.5% to 27%. Across four studies, the rate of recanalization ranged from 8.7% to 13%. Two cases of delayed rupture were reported; an additional four cases were found in case reports and case series. In only one previous case, the aneurysm was reported as previously untreated.

CONCLUSION

Early retrospective data has begun to define the history of WEB-treated aneurysms. Rupture of a previously unruptured, WEB-treated aneurysm with adequate initial occlusion is rare. We describe such a case with techniques for management, demonstrating that aneurysm recurrence and delayed rupture is possible despite good interim angiographic result. This report raises questions about follow-up for WEB-treated aneurysms.

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.

The Woven EndoBridge (WEB) device: feasibility, techniques, and outcomes after FDA approval

OBJECTIVE

Wide-neck bifurcation cerebral aneurysms have historically required either clip ligation or stent- or balloon-assisted coil embolization. This predicament led to the development of the Woven EndoBridge (WEB) aneurysm embolization system, a self-expanding mesh device that achieves intrasaccular flow disruption and does not require antithrombotic medications. The authors report their operative experience and 6-month follow-up occlusion outcomes with the first 115 aneurysms they treated via WEB embolization.

METHODS

The authors reviewed the first 115 cerebral aneurysms they treated by WEB embolization after FDA approval of the WEB embolization device (from February 2019 to January 2021). Data were collected on patient demographics and clinical presentation, aneurysm characteristics, procedural details, postembolization angiographic contrast stasis, and functional outcomes.

RESULTS

A total of 110 patients and 115 aneurysms were included in our study (34 ruptured and 81 unruptured aneurysms). WEB embolization was successful in 106 (92.2%) aneurysms, with a complication occurring in 6 (5.5%) patients. Contrast clearance was seen in the arterial phase in 14 (12.2%) aneurysms, in the capillary phase in 16 (13.9%), in the venous phase in 63 (54.8%), and no contrast was seen in 13 (11.3%) of the aneurysms studied. Follow-up angiography was performed on 60 (52.6%) of the aneurysms, with complete occlusion in 38 (63.3%), neck remnant in 14 (23.3%), and aneurysmal remnant in 8 (13.3%). Six (5.5%) patients required re-treatment for persistent aneurysmal residual on follow-up angiography.

CONCLUSIONS

The WEB device has been successfully used for the treatment of both unruptured and ruptured wide-neck bifurcation aneurysms by achieving intrasaccular flow diversion. Here, the authors have shared their experience with its unique technical considerations and device size selection, as well as critically reviewed complications and aneurysm occlusion rates.

Woven EndoBridge versus stent-assisted coil embolization of cerebral bifurcation aneurysms

OBJECTIVE

Stent-assisted coil (SAC) embolization has been the mainstay endovascular treatment for bifurcation aneurysms. The recent introduction of the Woven EndoBridge (WEB) device has presented an alternative endovascular treatment modality for these aneurysms. Direct comparisons of outcomes between these two modalities are limited in the literature. Here, the authors compared the outcomes of bifurcation aneurysms treated with SAC and WEB devices.

METHODS

This retrospective single-center study comprised 148 bifurcation aneurysms that were treated endovascularly with SAC or WEB devices between 2011 and 2019. The primary outcome was complete occlusion of the aneurysm at 6 months on catheter angiography.

RESULTS

The SAC and WEB cohorts comprised 85 and 63 aneurysms, respectively. The baseline characteristics were well balanced after inverse probability weight (IPW) adjustment, except for smoking status. The 6-month complete occlusion rate was higher in the WEB cohort than the SAC cohort (67.4% vs 40.6%; unadjusted OR [95% CI] 3.014 [1.385-6.563], p = 0.005). However, this difference in complete occlusion rates did not remain significant after IPW adjustment and multiple imputations. The neck remnant rate was lower in the WEB cohort than the SAC cohort (20% vs 50%; OR [95% CI] 0.250 [0.107-0.584], p = 0.001), and this difference remained significant after IPW adjustment (OR [95% CI] 0.304 [0.116-0.795], p = 0.015) and multiple imputations.

CONCLUSIONS

Use of SAC and WEB demonstrated comparable 6-month complete occlusion rates for bifurcation aneurysms. WEB appeared to be associated with a lower rate of neck remnant at 6 and 12 months compared with SAC. WEB was also associated with fewer complications and decreased retreatment rates compared with SAC.

Comparing treatment outcomes of various intracranial bifurcation aneurysms locations using the Woven EndoBridge (WEB) device

BACKGROUND

The Woven EndoBridge (WEB) device has Food and Drug Administration approval for treatment of wide-necked intracranial bifurcation aneurysms. The WEB device has been shown to result in adequate occlusion in bifurcation aneurysms overall, but its usefulness in the individual bifurcation locations has been evaluated separately only in few case series, which were limited by small sample sizes.

OBJECTIVE

To compare angiographic and clinical outcomes after treatment of bifurcation aneurysms at various locations, including anterior communicating artery (AComA), anterior cerebral artery (ACA) bifurcation distal to AComA, basilar tip, internal carotid artery (ICA) bifurcation, and middle cerebral artery (MCA) bifurcation aneurysms using the WEB device.

METHODS

A retrospective cohort analysis was conducted at 22 academic institutions worldwide to compare treatment outcomes of patients with intracranial bifurcation aneurysms using the WEB device. Data include patient and aneurysm characteristics, procedural details, angiographic and functional outcomes, and complications.

RESULTS

A total of 572 aneurysms were included. MCA (36%), AComA (35.7%), and basilar tip (18.9%) aneurysms were most common. The rate of adequate aneurysm occlusion was significantly higher for basilar tip (91.6%) and ICA bifurcation (96.7%) aneurysms and lower for ACA bifurcation (71.4%) and AComA (80.6%) aneurysms (p=0.04).

CONCLUSION

To our knowledge, this is the most extensive study to date that compares the treatment of different intracranial bifurcation aneurysms using the WEB device. Basilar tip and ICA bifurcation aneurysms showed significantly higher rates of aneurysm occlusion than other locations.

Treatment of a ruptured fetal-type posterior communicating aneurysm with a combined approach using the new contour neurovascular system

Fetal-type posterior communicating artery (FPCom) aneurysms are associated with higher rates of recurrence after endovascular treatment than aneurysms at other locations. We report the case of a patient with a subarachnoid haemorrhage and ruptured right-sided FPCom aneurysm. The patient underwent acute endovascular treatment with application of a novel combined approach-partial coiling to protect the dome and occlusion of the neck with a new flow-disrupter, endosaccular device, Contour (Cerus Endovascular)-as a stable, single-step treatment to prevent rebleeding in the acute stage and long-term potential recurrences.

Microsurgical clipping vs Woven EndoBridge (WEB) device for the management of unruptured wide-neck bifurcation aneurysms

The Woven EndoBridge device (WEB) was introduced in 2010 to treat wide-neck bifurcation aneurysms (WNBAs). Three landmark studies have been conducted to assess its safety and efficacy: WEBCAST, WEBCAST 2, and French Observatory Study. However, these studies have not compared its safety and efficacy to other treatment modalities. In this study, we compare WEB versus microsurgical clipping in the management of unruptured WNBA. We conducted a retrospective study of unruptured WNBA meeting the morphological criteria to be amenable for WEB treatment operated on at our institution. Surgical morbidity, mortality, and occlusion rates were assessed. We compared our results to those reported in the cumulative population of the three WEB landmark studies at 1 year. A total of 84 patients with 89 WNBA were included. The most common aneurysm location was the middle cerebral artery bifurcation (n = 67/89, 75%). No operative mortality was observed. Morbidity comprised small-vessel vasospasm (n = 1/89, 1%) resulting in hemiparesis vs. 3% morbidity for WEB (p = .324). All but one (n = 1/89, 1%) WNBA were completely occluded vs WEB occlusion rate of 53% at 1 year, statistically significantly worse (p < .001). In our analysis, we were not able to show superiority of WEB in terms of procedural morbidity in comparison to microsurgical clipping, defined as worsening in mRS. Microsurgical clipping achieves statistically significantly higher rates of complete aneurysm occlusion, thus posing the question of whether the WEB should be presented as a viable, comparable alternative to patients amenable to surgical treatment.

A single centre retrospective analysis of short- and medium-term outcomes using the Woven EndoBridge (WEB) device and identification of the device-to-aneurysm volume ratio as a potential predictor of aneurysm occlusion status

BACKGROUND

The Woven EndoBridge (WEB) is a potential treatment option in patients with wide-necked bifurcation aneurysms (WNBAs). We analysed our WEB device outcomes (occlusion rates and complications) and studied factors that may predict aneurysm occlusion status at short- and medium-term follow-up.

METHODS

74 patients with ruptured and unruptured aneurysms underwent treatment with the WEB device over a 5-year period. Simple hypothesis tests assessed differences between treated ruptured and unruptured aneurysms. Univariable binary logistic regression was used to assess the effect of age, gender, and aneurysm location on the likelihood of adequate occlusion at six months. Aneurysm dimentions including device-to-aneurysm volume (DAV) ratios were compared between adequately and inadequately occluded aneurysms.

RESULTS

The mean age at the time of the procedure was 58.2 years (SD 12.2; range 34-88) and the male to female ratio was 1:2.7. Middle cerebral artery (MCA) was the most commonly treated aneurysm. There was no significant difference in occlusion rates between ruptured and unruptured aneurysms. The six- and 18-month angiographic follow-up data was available for 61 and 32 patients respectively with adequate occlusion rates of 78.7% (48/61) and 78.1% (25/32). Procedure-related complications occurred in 6 patients (8.1%). Baseline DAV ratio was found to be significantly higher in aneurysms that were adequately occluded at both short- (p-value 0.015) and medium-term (p-value 0.047) follow-up.

CONCLUSIONS

WEB devices are a safe and effective endovascular treatment option for WNBAs. WEB device selection incorporating the peri-procedural DAV ratio may help improve the accuracy of device sizing thereby improving the successful occlusion rate.

Comprehensive review of the recent advances in devices for endovascular treatment of complex brain aneurysms

The International Subarachnoid Aneurysm Trial (ISAT) showed superiority for endovascular treatment of ruptured aneurysms and technology has since moved on rapidly. Many approaches and technology now exist for the endovascular management of ruptured and unruptured intracranial aneurysms, which reflects their varied nature - there is no one-size-fits-all technique. We aim to provide an overview of the various classes of device and the major developments over the past decade. Coiling is the oldest of the technology and continues to demonstrate high levels of occlusion and acceptable risks, making it the default treatment choice, particularly in the acutely ruptured aneurysm setting. Advances on coiling include the use of adjuncts such as balloons, stents and fully retrievable temporary neck-bridging devices, which have facilitated the treatment of more complex aneurysms. Flow divertors have also revolutionised complex aneurysm treatment with small added risk in acute aneurysm treatment and seek to remodel the aneurysm-vessel interface without accessing the aneurysm sac. The latest development and most promising avenue appears to be intrasaccular flow disrupting devices like WEB, Contour and Neqstent that provide excellent opportunities to treat wide neck complex aneurysm with minimal mortality and morbidity and good occlusion rates and may in future replace a significant number of stent-assisted coiling too.