Should indications for WEB aneurysm treatment be enlarged? Report of a series of 20 patients with aneurysms in “atypical” locations for WEB treatment

The Management of Intracranial Aneurysms: Current Trends and Future Directions

Intracranial aneurysms represent a major global health burden. Rupture of an intracranial aneurysm is a catastrophic event. Without access to treatment, the fatality rate is 50% in the first 30 days. Over the last three decades, treatment approaches for intracranial aneurysms have changed dramatically. There have been improvements in the medical management of aneurysmal subarachnoid haemorrhage, and there has been an evolution of treatment strategies. Endovascular therapy is now the mainstay of the treatment of ruptured intracranial aneurysms based on robust randomised controlled trial data. There is now an expansion of treatment indications for unruptured intracranial aneurysms to prevent rupture with both microsurgical clipping and endovascular treatment. Both microsurgical and endovascular treatment modalities have evolved, in particular with the introduction of innovative endovascular treatment options including flow diversion and intra-saccular flow disruption. These novel therapies allow clinicians to treat more complex and previously untreatable aneurysms. We aim to review the evolution of treatment strategies for intracranial aneurysms over time, and discuss emerging technologies that could further improve treatment safety and functional outcomes for patients with an intracranial aneurysm.

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.

How a decade of aneurysms embolization with the Woven EndoBridge has changed our understanding and practices?

BACKGROUND

Safety and efficacy of the WEB (Woven EndoBridge) device have been extensively evaluated in several good clinical practice studies. Nonetheless, the WEB had several structural evolutions overtime up to the fifth generation WEB device (WEB17). Here, we tried to understand how this may have modified our practices and enlarged our indications for its use.

METHODS

We retrospectively analyzed data from all patients with aneurysms treated (or intended to be treated) with a WEB at our institution between July 2012 and February 2022. The time frame was split in two periods: before and after the arrival of the WEB17 in our center (February 2017).

RESULTS

252 patients with 276 wide-necked aneurysms were included; 78 aneurysms (28.2%) were ruptured. Successful embolization with a WEB device was achieved in 263/276 aneurysms (95.3%). With the availability of WEB17, treated aneurysms were significantly smaller (8.2 mm versus 5.9 mm, p<0.001) and off-label location significantly increased (4.4% versus 17.3%, p = 0.02) with an increase of sidewall aneurysm (4.4% versus 11.6%, p = 0.06). Also, WEB were more significantly oversized (1.05 versus 1.11, p<0.01). Adequate and complete occlusion rates increased constantly during the two periods (54.8% versus 67.5%, p = 0.08 and 74.2% versus 83.7%, p = 0.10, respectively). The proportion of ruptured aneurysms slightly increased between the two periods (24.6% versus 29.5%, p = 0.44).

CONCLUSIONS

Over the first decade of its availability, the WEB device usage shifted towards smaller aneurysms and broader indications, including ruptured aneurysms. The oversizing strategy also became the standard of practice for WEB deployment in our institution.

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.

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.

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.

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.

Intrasaccular flow disruption for brain aneurysms: a systematic review of long-term outcomes

OBJECTIVE

The long-term safety and efficacy of intrasaccular flow disruption (IFD) for the treatment of brain aneurysms remain unclear. With accumulating experience and increasing use of IFD devices, recent studies have provided additional data regarding their outcomes. This review summarizes the long-term outcomes of IFD-treated brain aneurysms.

METHODS

A systematic literature review was performed on May 23, 2021, in PubMed, Web of Science, and Ovid MEDLINE for aneurysm treatment outcomes with IFD devices. Procedural details, including use of adjunctive devices and complications, were collected. The quality of studies was assessed using the Downs and Black checklist. Angiographic outcomes were classified as complete occlusion, residual neck, and residual aneurysm. Other outcomes included need for retreatment, permanent neurological deficit, and mortality. Pooled analyses were performed.

RESULTS

The final analysis comprised 1217 patients with 1249 aneurysms from 22 studies. The mean aneurysm diameter and neck width were 6.9 and 4.5 mm, respectively, and 27.6% of aneurysms were ruptured. The complete occlusion rates at 12 months and final follow-up (pooled mean duration 15.7 months) were 50.1% and 58.2%, respectively. Adjunctive devices were used in 6.4% of cases. The rates of hemorrhage, symptomatic infarction, permanent neurological deficit, and mortality were 1.2%, 2.8%, 1.0%, and 2.6%, respectively.

CONCLUSIONS

IFD is a very safe treatment for appropriately selected brain aneurysms with low complication and neurological deterioration rates. However, complete occlusion is achieved in only half of IFD-treated aneurysms at 1 year with a modest increase beyond this time point. As the majority of the studies were single arm, the pooled data are subject to selection and reporting biases. Future device developments, increased operator experience, and direct comparisons with alternative endovascular strategies and surgical clipping may clarify the role of IFD in aneurysm management.

Ten Years of Clinical Evaluation of the Woven EndoBridge: A Safe and Effective Treatment for Wide-Neck Bifurcation Aneurysms

Intrasaccular flow disruption is an innovative approach for the endovascular treatment of intracranial aneurysms. As of now, only one device is currently available worldwide: the Woven EndoBridge (WEB) device (MicroVention, Aliso Viejo, CA, USA). After 10 years of clinical use and careful clinical evaluation of the WEB device by multiple prospective, multicenter studies, this article is summarizing the current knowledge regarding this endovascular technique; indications, modalities, safety and efficacy of the WEB procedure are described.

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.

Comparison of operating room variables, radiation exposure and implant costs for WEB versus stent assisted coiling for treatment of wide neck bifurcation aneurysms

BACKGROUND

The WEB device offers another option for treating wide neck bifurcation aneurysms (WNBA). The objective was to compare procedure variables, radiation and implant cost between WEB and stent assisted coiling (SAC) for WNBA.

METHODS

A retrospective comparison of similarly sized WNBA treated with SAC or WEB over 5-years was performed. The operating room (arrival-departure), anesthesia (intubation-extubation), procedure duration (puncture-closure), fluoroscopy time and radiation dose(m-Gy) were recorded from the patients' charts. Implant cost per case of all implants (stents, coils, WEB) that were opened whether deployed or not was captured including any coils used in the WEB cases. The implant cost represented the true cost incurred by the institution.

RESULTS

There were 46 WEB and 41 SAC cases with no significant difference in aneurysm size. There were more MCA and ACOMM (p = 0.005) and more ruptured aneurysms (p = 0.02) in the WEB group. Regarding procedure variables (hours:minutes): Operating room time WEB 2:31 (±0:37) versus SAC 3:41 (±0:50) (p < 0.0001); anesthesia duration WEB 2:05 (±0:31) versus SAC 3:13 (±0:51) (p < 0.0001) and procedure duration WEB 1:16 (±0:29) versus SAC 2:09 (±0:46) (p < 0.0001). Regarding radiation: Fluoroscopy time WEB 0:34 (±0:18) versus SAC 1:06 (±0:35) (p < 0.0001) and radiation dose WEB 2392(±1086)m-Gy versus SAC 3442 (±1528)m-Gy (p = 0.0007). The implant cost was $17,028(±$5,527) for the WEB versus $23,813 (±$7,456) for the SAC group (p < 0.0001).

CONCLUSION

The WEB group had significantly shorter operating room, procedure and anesthesia duration compared to the SAC group. The radiation dose and fluoroscopy time was lower for the WEB group. The total implant cost per case was significantly lower for the WEB versus the SAC group.

WEB device for treatment of posterior communicating artery aneurysms

BACKGROUND

Woven EndoBridge (WEB) device treatment of wide-neck bifurcation aneurysms has proved to be safe and effective, but the use of these devices in sidewall aneurysms has been reported only in a small number of case series.

OBJECTIVE

To report our results in a cohort of consecutive patients in whom a WEB device was used as first-line treatment for posterior communicating artery (PComA) aneurysms.

METHODS

We conducted a retrospective analysis of a prospectively maintained database of PComA aneurysms treated with a WEB device in our institution from June 1, 2012 to November 15, 2020. Clinical and radiological findings were evaluated at immediate and last follow-up.

RESULTS

A total of 219 aneurysms were treated with a WEB device, including 15 PComA aneurysms in 15 patients, 10 of which were ruptured. Aneurysms were wide necked, with a mean aspect ratio of 1.6 (range 0.7-3.0) and a mean neck size of 4.2 mm (range 2.6-7.4 mm). No intraoperative rupture occurred and only one thromboembolic event was noted. Among the group with at least a 3-month digital subtraction angiography (DSA) follow-up, complete and adequate occlusion were obtained in 54% and 72%, respectively (average follow-up 13 months). Re-treatment was needed for two initially ruptured aneurysms. No procedure-related morbidity or mortality was reported.

CONCLUSION

This series suggests the high safety profile of WEB devices even when used in off-label indications. Treatment with these devices seems to be a valuable strategy for ruptured wide-neck PComA aneurysms, avoiding the need for antiplatelet medication. However, occlusion rates should be investigated in further larger studies.

Intracranial aneurysm treatment with WEB and adjunctive stent: preliminary evaluation in a single-center series

Background

Intrasaccular flow disruption with WEB is a safe and efficacious technique that has significantly changed endovascular management of wide-neck bifurcation aneurysms (WNBAs). Use of stent in combination with WEB is occasionally required. We analyzed the frequency of use, indications, safety, and efficacy of the WEB–stent combination.

Methods

All aneurysms treated with WEB and stent were extracted from a prospectively maintained database. Patient and aneurysm characteristics, complications, and anatomical results were independently analyzed by a physician independent of the procedures.

Results

From June 2011 to January 2020, 152 patients with 157 aneurysms were treated with WEB. Of these, 17/152 patients (11.2%) with 19/157 aneurysms (12.1%) were treated with WEB device and stent. Indications were very wide neck with a branch emerging from the neck in 1/19 (5.2%) aneurysms and WEB protrusion in 18/19 (94.7%). At 1 month, no morbimortality was reported. At 6 months, anatomical results were complete aneurysm occlusion in 15/17 aneurysms (88.2%), neck remnant in 1/17 (5.9%), and aneurysm remnant in 1/17 (5.9%). At 12 months, there was complete aneurysm occlusion in 13/14 aneurysms (92.9%) and neck remnant in 1/14 (7.1%).

Conclusions

Combining WEB and stent is a therapeutic strategy to manage WNBA. In our series, this combination was used in 11.2% of patients treated with WEB, resulting in no morbidity or mortality with a high efficacy at 6 and 12 months (complete aneurysm occlusion in 88.2% and 92.9%, respectively).

Woven EndoBridge device shape modification can be mitigated with an appropriate oversizing strategy: a VasoCT based study

BACKGROUND

The Woven EndoBridge (WEB) shape modification (WShM) during follow-up may be a potential cause of poor angiographic outcomes. WShM predisposing factors have not yet been determined. Our systematic use of rotational cone beam computed tomography (VasoCT) imaging during follow-up allowed us to perform the first quantitative analysis of the shape of WEBs over time. Our goal was to identify possible strategies to reduce the occurrence of this phenomenon.

METHODS

All patients treated in our hospital with a WEB device between October 2015 and January 2019 were included. Using VasoCT acquisitions, systematically performed after implantation and during follow-up, we analyzed WEB morphology. WShM was defined as the percentage reduction in the distance between the two WEB markers.

RESULTS

Sixty-three aneurysms treated with a WEB device were finally included in this analysis. At the last follow-up (mean 15.5 months), mean WShM was 48%±24. The mean WShM was significantly higher in the aneurysm recurrence group than in the adequate occlusion group (51±6.5% vs 36±3.4%, difference 15% points (95% CI 0.7 to 30); p<0.05). Conversely, the extent of WShM did not directly correlate with occlusion rates. Indeed, 32% of completely occluded aneurysms presented severe WShM (≥50%). Importantly, the absence of WShM guaranteed complete occlusion in our study (n=12). We demonstrated that oversizing the width of the WEB significantly correlated with WShM reduction during follow-up (r=-0.38, p=0.002).

CONCLUSION

WShM can be partly overcome by use of an appropriate width oversizing strategy that could lead to improved angiographic results.

Widening the Indications for Intrasaccular Flow Disruption: WEB 17 in the Treatment of Aneurysm Locations Different from Those in the Good Clinical Practice Trials

BACKGROUND AND PURPOSE

The safety and efficacy of the Woven EndoBridge (WEB) device has been shown in multiple good clinical practice trials, whereas aneurysm locations in these trials were restricted to bifurcation aneurysms located at the circle of Willis (MCA bifurcation, ICA bifurcation, anterior communicating artery, basilar artery tip). Our aim was to evaluate angiographic and clinical results with the WEB 17 in aneurysm locations that were excluded from the good clinical practice trials, assuming that the angiographic and clinical results are similar to those of the good clinical practice trials for aneurysms in traditional locations.

MATERIALS AND METHODS

We performed retrospective analysis of immediate and follow-up results of aneurysms in locations outside the good clinical practice trials in which the WEB 17 was used on an intention-to-treat approach.

RESULTS

Between June 2017 and May 2020, forty-seven aneurysms in 44 patients met the inclusion criteria. Aneurysm locations were the ICA posterior communicating artery in 19 (40.3%), the ICA paraophthalmic or choroidal locations in 4 (8.6%), anterior cerebral artery A2 segment in 13 (27.7%), MCA M1 segment in 2 (4.3%), posterior cerebral artery P2 segment in 2 (4.3%), PICA in 3 (6.4%), and the superior cerebellar artery in 4 (8.4%) cases. The procedure-related morbidity and mortality rates in the entire series were 0.0%. The early and late (<12 and >12 months) complete occlusion rates were 63.9% (23/36) and 77.8% (14/18), respectively.

CONCLUSIONS

The WEB 17 is safe and effective in aneurysm locations different from the traditional bifurcation aneurysms included in the good clinical practice trials. Further studies will help to define the entire spectrum of aneurysm morphologies and locations suitable for the WEB 17.

Comparison of Woven EndoBridge device sizing with conventional measurements and virtual simulation using the Sim&Size software: a multicenter experience

BACKGROUND

Selection of the appropriate device size mandatory during aneurysm treatment with a Woven EndoBridge (WEB). We aimed to investigate if virtual simulation with Sim&Size software may have an impact on technical, angiographic, and clinical outcomes after WEB treatment.

METHODS

Data from two large-volume centers were collected and compared (January 2017-January 2020). Virtual simulation was systematically adopted in one center, while conventional sizing was used in the other one. Outcomes were the duration of intervention, the radiation dose (in milligrays, the number of corrective interventions for inappropriate WEB size, the number of WEBs not deployed, angiographic occlusion, and complications. Univariate and multivariate linear models were adopted.

RESULTS

A total of 186 aneurysms were treated with WEB (109 with and 77 without virtual simulation). Patient characteristics and aneurysm features were comparable among virtual and conventional sizing, except for mean age (62.2±11.8 years and 56.2±10.1 years, P=0.0004) and median aspect ratio (1.6, IQR=1.2-2 and 1.2, IQR=1-1.6, P=0.0001). Years of operator experience were comparable. Virtual simulation was independently associated with shorter intervention time (45 min, IQR=33-63.5 min vs 63.5 min, IQR=41-84.7 min, P=0.0001), lower radiation dose (1051 mGy, IQR=815-1399 mGy vs 1207 mGy, IQR=898-2084 mGy, P=0.0001), and lower number of WEBs not deployed (26/77=33.7% vs 8/109=7.3%, P=0.0001). The need for additional maneuvers was significantly lower in the virtual simulation group (5/109=4.6% vs 12/77=15.6%, P=0.021). Angiographic outcomes and complications were comparable.

CONCLUSIONS

In this multicenter experience, virtual simulation with Sim&Size software seems to facilitate the selection of the appropriate WEB device for aneurysm treatment, reducing the time of intervention, the radiation dose, the number of devices not deployed, and the need for corrective interventions.

TRIAL REGISTRATION NUMBER

clinicaltrials.gov Identifier: NCT04621552.

Two-Center Experience in the Endovascular Treatment of Intracranial Aneurysms Using the Woven EndoBridge 17 Device Including Midterm Follow-Up Results: A Retrospective Analysis

BACKGROUND AND PURPOSE

The Woven EndoBridge device proved its effectiveness in the treatment of ruptured and unruptured intracranial aneurysms as a stand-alone device. Before 2016, Woven EndoBridge deployment required at least a 0.021-inch microcatheter. In 2016, a smaller device, the Woven EndoBridge 17 with finer size increments that used a 0.017-inch microcatheter, was introduced. We retrospectively analyzed our initial and follow-up results with the Woven EndoBridge 17 in ruptured and unruptured aneurysms.

MATERIALS AND METHODS

One hundred twenty-seven intracranial aneurysms in 117 patients were scheduled for treatment with the Woven EndoBridge 17 between June 2017 and February 2019. Twenty-nine aneurysms were ruptured.

RESULTS

Treatment was performed as intended in 124 of 127 cases (97.6%). Additional devices such as stents or coils were used in 12 cases (9.7%). Five thromboembolic complications and 1 hemorrhagic complication were encountered, resulting in clinical deterioration in 2 patients. The overall morbidity and mortality in the entire series have been 1.7% and 0.0% to date, respectively. The follow-up results at 3 and 12 months revealed complete occlusion in 76.1% (70/92) and 78.0% (32/41).

CONCLUSIONS

The Woven EndoBridge 17 device is safe in the treatment of small broad-based aneurysms without the general need for additional devices. The low complication rate and the promising follow-up results underline the value of this technique in a growing range of endovascular treatment options for intracranial aneurysms.

Woven EndoBridge Device immediate post-detachment tilt with later displacement: Case report, rescue techniques, and review of the literature

The Woven EndoBridge Device (WEB) is efficient and safe in the treatment of wide-neck bifurcation intracranial aneurysms. A crucial step in operative planning is establishing the appropriate dimension of the device, and there are limitations to the therapeutic solutions provided by WEBs. We describe a case of a right middle cerebral artery bifurcation wide-neck aneurysm treated with WEB. After the initial deployment of a WEB proven oversized, we substituted it with a smaller one that presented immediate post-detachment intra-aneurysmal tilt probably resulting from undersizing. The 24-h angiographic control identified a partial displacement of the device in the superior middle cerebral artery branch. We describe rescue techniques with review of the literature and our treatment strategy, including effort to reposition the device followed by stent deployment. The treatment was electively completed by the coil-through technique. The post-detachment WEB tilt should be considered an unstable position and treated either by removal of the device or with adjunctive implants. Each WEB size adapts to a range of aneurysmal height and width. This range is not always the same for each specific WEB dimension, based on the table provided by the manufacturer. This eventually predisposes to a different behavior of different WEB sizes regarding the modification of the device's height in relation to the modification of the diameter after deployment.

WEB as a combined support and embolization device in a giant partially thrombosed donut-shaped aneurysm

BACKGROUND

Giant partially thrombosed aneurysms are challenging lesions for which treatment can be difficult due to their unfavourable anatomical configuration and abnormal flow conditions.

CASE DESCRIPTION

The patient presented in this report suffered from a symptomatic giant partially thrombosed donut-shaped aneurysm of the left-sided supraophthalmic internal carotid artery. Due to the location and the size of the aneurysm, endovascular treatment was performed. Navigation of the microcatheter-microwire-system distal to the aneurysm for stent deployment was technically not possible due to limited support, caused by the large aneurysm. Therefore, a WEB device was placed in the distal leg of the donut-shaped aneurysm. Additionally to the occlusion of this part of the aneurysm, the WEB device enabled enough support to navigate the microcatheter-microwire-system distal to the aneurysm. After deployment of a flow-diverting stent, coiling of the aneurysm was performed. Follow-up angiography showed complete occlusion of the aneurysm. The patient suffered from severe headaches which were no longer present 6 months after treatment.

CONCLUSIONS

The WEB intraaneurysmal flow diverter can be effectively used as combined support and embolization device for the treatment of complex aneurysms in selective cases where other catheterization and embolization strategies have failed.

Predicting Factors of Angiographic Aneurysm Occlusion after Treatment with the Woven EndoBridge Device: A Single-Center Experience with Midterm Follow-Up

BACKGROUND AND PURPOSE

Flow disruption with the Woven EndoBridge is increasingly used for the treatment of intracranial aneurysms. We examined factors leading to aneurysm occlusion and Woven EndoBridge shape change during a midterm follow-up.

MATERIALS AND METHODS

Patients with a minimum 12-month angiographic follow-up were included. Through a univariate and multivariate analysis, independent predictors of adequate occlusion (Raymond-Roy 1/Raymond-Roy 2) and Woven EndoBridge shape change (decrease of the height of the device) were assessed.

RESULTS

Eighty-six patients/aneurysms were included. The aneurysm mean size was 5.5 mm (range, 3-11.5 mm). The most common locations were the MCA (43/86 = 50%), basilar tip (13/86 = 15.1%), and anterior communicating artery (12/86 = 14%). Twenty-one patients (21/86 = 24%) had acute SAH. Immediate and long-term Raymond-Roy 1/Raymond-Roy 2 occlusion rates were 49% (42/86) and 80% (68/86), respectively. Woven EndoBridge shape change was detected among 22% (19/86) of cases. At binary logistic regression, wide ostium (≥4 mm) (OR = 0.2; 95% CI, 0.01-1; P = .04) and regular aneurysm morphology (OR = 5.9; 95% CI, 1.4-24; P = .01) were independent factors of incomplete and adequate aneurysm occlusion, respectively. In addition, irregular morphology (OR = 5.4; 95%CI, 1.4-19; P = .01) and a wide ostium (OR = 9.8; 95% CI, 1.6-60; P = .03) significantly increased the probability of the Woven EndoBridge shape change. Decrease of the Woven EndoBridge height was more common among incompletely occluded aneurysms (6/12 = 50% versus 13/74 = 17.5%), but it was not an independent prognosticator of occlusion at the multivariate model.

CONCLUSIONS

The likelihood of good occlusion was 5 times lower in the presence of a wide ostium, whereas aneurysms with regular morphology were 6 times more likely to be occluded. Woven EndoBridge shape modification was strongly influenced by the aneurysm shape and ostium size, and it was not independently associated with the angiographic occlusion.

WEB-only treatment of ruptured and unruptured intracranial aneurysms: a retrospective analysis of 47 aneurysms

BACKGROUND

WEB (Woven EndoBridge) device is an intrasaccular flow diverter designed for endovascular treatment of intracranial aneurysms. Recent clinical trials showed good feasibility, safety, and efficacy profiles. In most of the published studies however, aneurysms treated with adjunctive devices other than WEB such as coils or stents were included which might make it difficult to reflect the real potential of this device. The purpose of this single-center study was to present the results of ruptured and unruptured aneurysms treated only with WEB device.

METHOD

Between April 2013 and July 2018, 47 (ruptured, 12; 25.5%) intracranial aneurysms treated only with WEB and a follow-up of at least 3 months were included in the study. Angiographic outcome at follow-up, peri-procedural complication rate, and rate of retreatment were recorded.

RESULTS

Of the 47 aneurysms, 12 (25.5%) were ruptured. The mean size of the aneurysms was 6.3 mm (ruptured, 5.4 mm; unruptured, 6.6 mm). Median follow-up period was 9 months. Complete occlusion was observed in 26/47 aneurysms (55.3%; ruptured, 66.6%; unruptured, 51.4%). Thirteen aneurysms (27.6%; ruptured, 16.6%; unruptured, 31.4%) showed a neck remnant. In 4/47 aneurysms (8.5%; ruptured, 8%; unruptured, 8.5%), persistent contrast enhancement inside the WEB was recorded. In 4/47 patients (8.5%; ruptured, 8%; unruptured, 8.5%), an aneurysm remnant was noted. Adequate occlusion (complete occlusion and neck remnant) was observed in 43/47 aneurysms (91.4%; ruptured, 91.6%; unruptured, 91.4%). Retreatment rate was 6.3% (ruptured, 8%; unruptured, 5.7%). Six (12.7%; ruptured, 25%; unruptured, 8.5%) thromboembolic events were recorded. Hemorrhagic complications occurred in two patients (4.2%; ruptured, 16.6%; unruptured, 0%).

CONCLUSIONS

WEB enables adequate occlusion of ruptured and unruptured intracranial aneurysms mostly without requirement of long-term antiplatelet therapy. The benefit is seen especially by the wide-necked aneurysms, but indications should be extended to include narrow-necked, smaller, and side-wall aneurysms.

WEB embolization versus stent-assisted coiling: comparison of complication rates and angiographic outcomes

Background

Intrasaccular flow disruption represents a new paradigm in endovascular treatment of wide-necked bifurcation aneurysms.

Objective

To perform a matched case–control study comparing complications and angiographic outcome using the Woven Endobridge (WEB) device and stent-assisted coiling (SAC).

Methods

Sixty-six patients treated with the WEB at three German tertiary care centers were included and matched with 66 patients treated with SAC based on aneurysm location and unruptured/ruptured aneurysm status. Parameters were retrospectively analysed and compared between the treatment groups using inverse probability of treatment weighting (IPTW) with propensity scores.

Results

Procedural complication rates were 12.1% in the WEB group and 21.2% in the SAC group, which was statistically significant after IPTW adjustment (OR=2.2, 95% CI 1.08 to 4.4, p=0.03). Favourable outcome (modified Rankin scale score ≤2) was achieved by 57/66 (86.4%) in the WEB group and 57/66 (86.4%) in the SAC group (p=1.0). At mid-term follow-up, a similar number of aneurysms achieved adequate occlusion (complete occlusion or neck remnant) in the WEB group (93.9%) and in the SAC group (93.9%, p=1.0). Re-treatment was performed in 10.6% after WEB embolization and 12.1% after SAC (p=1.0).

Conclusions

The WEB provides similar mid-term aneurysm occlusion rates to those of SAC, with no additional morbidity and potentially lower complication rates. Long-term outcome analysis will provide a definite conclusion on the use of WEB for intracranial aneurysms.

Safety and efficacy of aneurysm treatment with WEB in the cumulative population of three prospective, multicenter series

BACKGROUND

Flow disruption with the WEB is an innovative endovascular approach for treatment of wide-neck bifurcation aneurysms. Initial studies have shown a low complication rate with good efficacy.

PURPOSE

To report clinical and anatomical results of the WEB treatment in the cumulative population of three Good Clinical Practice (GCP) studies: WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm), French Observatory, and WEBCAST-2.

METHODS

WEBCAST, French Observatory, and WEBCAST-2 are single-arm, prospective, multicenter, GCP studies dedicated to the evaluation of WEB treatment. Clinical data were independently evaluated. Postoperative and 1-year aneurysm occlusion was independently evaluated using the 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.

RESULTS

The cumulative population comprised 168 patients with 169 aneurysms, including 112 female subjects (66.7%). The patients' ages ranged between 27 and 77 years (mean 55.5±10.2 years). Aneurysm locations were middle cerebral artery in 86/169 aneurysms (50.9%), anterior communicating artery in 36/169 (21.3%), basilar artery in 30/169 (17.8%), and internal carotid artery terminus in 17/169 (10.1%). The aneurysm was ruptured in 14/169 (8.3%). There was no mortality at 1 month and procedure/device-related morbidity was 1.2% (2/168). At 1 year, complete aneurysm occlusion was observed in 81/153 aneurysms (52.9%), neck remnant in 40/153 aneurysms (26.1%), and aneurysm remnant in 32/153 aneurysms (20.9%). Re-treatment was carried out in 6.9%.

CONCLUSIONS

This series is at the moment the largest prospective, multicenter, GCP series of patients with aneurysms treated with WEB. It shows the high safety and good mid-term efficacy of this treatment.

CLINICAL TRIAL REGISTRATION

French Observatory: Unique identifier (NCT18069); WEBCAST and WEBCAST-2: Unique identifier (NCT01778322).

Evaluation of safety, efficacy and clinical outcome after endovascular treatment of aneurysmal subarachnoid hemorrhage in coil-first setting. A 10-year series from a single center

INTRODUCTION

The endovascular treatment (EVT) of ruptured cerebral aneurysms has been widely adopted after the publication of the International Subarachnoid Aneurysm Trial. In this study, we sought to evaluate the safety and efficacy of the EVT for ruptured aneurysms based on 10-year series from a single center with coil-first strategy.

METHODS

All patients with aneurysmal subarachnoid hemorrhage (aSAH) treated between 2007 and 2016 were retrospectively reviewed and divided according to initial treatment into an EVT and a microsurgical clipping (MSC) group. Clinical and radiological findings at presentation, treatment modalities and procedural complications were recorded. The angiographic and clinical outcome was compared between the two groups.

RESULTS

A total of 587 patients with aSAH were reviewed (452 EVT, 135 MSC). There were no significant differences in mean age or the Hunt and Hess grades. Parenchymal hemorrhage (PH) was more frequent in the MSC. Procedure related complications of the acute treatment were recorded in 5.5% and 32% in the EVT and MSC, respectively. The rate of retreatment was 21.9% in the EVT and 5.9% in the MSC. Late rehemorrhage was not observed in either group. There was no significant difference in the clinical outcome between the two treatment groups after adjustment for other prognostic factors.

CONCLUSION

The majority of ruptured intracranial aneurysms can be managed via an endovascular approach in the acute phase with excellent safety profile and good efficacy. Despite the high rate of reperfusion after primary endovascular approach, retreatment has a very low rate of complications and the rate of recurrent hemorrhage is very low.

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

BACKGROUND AND PURPOSE

Flow disruption with the Woven EndoBridge (WEB) device is an innovative technique for the endovascular treatment of wide-neck bifurcation aneurysms. The initial version of the device (WEB Double-Layer) was evaluated in the WEB Clinical Assessment of IntraSaccular Aneurysm Therapy (WEBCAST) study, whereas the French Observatory study evaluated both WEB Double-Layer and Single-Layer versions of the device. WEBCAST 2 was designed to evaluate the WEB Single-Layer with Enhanced Visualization.

MATERIALS AND METHODS

Patients with wide-neck bifurcation aneurysms for which WEB treatment was possible were included. Clinical data including adverse events and clinical status at 1 month and 1 year were collected and analyzed. A core laboratory evaluated anatomic results at 1 year following the procedure.

RESULTS

Ten European neurointerventional centers included 55 patients (38 women; 27-77 years of age; mean, 54.4 ± 10.0 years) with 55 aneurysms. Aneurysm locations were the middle cerebral artery in 25 aneurysms (45.5%), the anterior communicating artery in 16 (29.1%), the basilar artery in 9 (16.4%), and the internal carotid artery terminus in 5 (9.1%). Procedural morbidity and mortality at 1 month were, respectively, 1.8% (1/55 patients) and 0.0% (0/55 patients). Morbidity and mortality at 1 year were, respectively, 3.9% (2/51 patients) and 2.0% (1/51 patients). At 1 year, complete occlusion was observed in 27/50 aneurysms (54.0%); neck remnant, in 13/50 (26.0%); and aneurysm remnant, in 10/50 (20.0%) (adequate occlusion in 40/50, 80.0%).

CONCLUSIONS

WEBCAST 2 confirms the high safety and efficacy of WEB aneurysm treatment demonstrated in the WEBCAST and French Observatory studies.