Woven Endobridge (WEB) device for endovascular treatment of complex unruptured aneurysms—a single center experience

Higher risk of recurrence in partially thrombosed cerebral aneurysms post-WEB (Woven EndoBridge) device treatment: insights from the WorldWideWEB Consortium registry

BACKGROUND

The Woven EndoBridge (WEB) device is a prevalent treatment for intracranial aneurysms. While many studies have assessed the obliteration rate post-WEB embolization, few have focused on long-term outcomes in partially thrombosed aneurysms.

OBJECTIVE

To assess whether partially thrombosed aneurysms are at higher risk of recurrence or retreatment following WEB embolization compared with non-thrombosed aneurysms.

METHODS

We evaluated data from 22 academic institutions, focusing on previously untreated cerebral aneurysms treated with the WEB device. Logistic regression was utilized to analyze factors predicting long-term aneurysm obliteration and retreatment necessity.

RESULTS

Among 1303 patients, 26 presented with a partially thrombosed aneurysm. In the partially thrombosed group, the mean aneurysm maximal diameter was 10.7±4 mm with a neck ratio of 1.99±1.19 mm, larger than in the control group where the mean aneurysm maximal diameter was 6.81±2.37 mm with a neck ratio of 1.64±0.51 mm (P<0.001 for both maximal diameter and neck ratio). At the final follow-up, partially thrombosed aneurysms treated by the WEB device had a 38.5% retreatment rate, compared with 7.0% for non-thrombosed aneurysms (P<0.001). Among partially thrombosed aneurysms, the Raymond-Roy type IIIa/b occlusion rate was higher (38.5% vs 9.9%, P<0.001). On multivariate analysis, partially thrombosed aneurysms compared with non-thrombosed aneurysms had an increased rate of retreatment (OR 3.64, 95% CI 1.28 to 10.1).

CONCLUSION

Partially thrombosed aneurysms are associated with a poorer occlusion rate and a higher rate of retreatment following WEB embolization. For partially thrombosed aneurysms, the WEB device appears suboptimal as a first-line treatment, and therefore alternative techniques should be prioritized.

A core-lab adjudicated analysis of single-stent assisted coiling of wide-neck bifurcation aneurysms

BACKGROUND AND PURPOSE

Core-lab adjudicated data regarding the efficacy of the single-stent assisted aneurysm coiling technique 'L-stenting' are lacking. We present a multicenter, core-lab adjudicated study evaluating the safety and effectiveness of single-stent assisted coiling in the treatment of wide-neck bifurcation aneurysms (WNBAs).

METHODS

Consecutive patients who underwent L-stenting for WNBAs at three academic institutions between 2015 and 2019 were included in this retrospective study. Clinical safety and efficacy outcomes were gathered from the patient chart, and angiographic imaging was evaluated by core lab analysis. Safety and efficacy outcomes were summarized and predictors of safety and efficacy were calculated.

RESULTS

Of 128 patients treated, 124 had angiographic outcome data at last follow-up. Of those, 110 had adequate (core-lab adjudicated modified Raymond Roy (mRR) score of 1 or 2) occlusion (88.7%). During follow-up, 19 patients (14.8%) required retreatment. There were 17 complications experienced in 12 patients: intraoperative (n=8, 6.25%), perioperative (n=5, 3.9%), or delayed (n=6; n=4 attributed to device/procedure, 3.1%). Significant predictors of complete occlusion were smaller aneurysm size and use of the jailing technique (P=0.0276). Significant predictors of retreatment were larger size, neck size, and larger dome to neck ratio (P=0.0008).

CONCLUSION

This study provides multicenter, core-lab adjudicated angiographic data regarding the efficacy of single-stent assisted coiling for WNBAs. This study acts as a validated comparator for future studies investigating novel devices or techniques for treating this challenging subgroup of aneurysms.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSIONS

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

Silk + flow-diverter stent for the treatment of intracranial aneurysms associated with balloon angioplasty: A retrospective study

Background

The silk + flow-diverter stent is increasingly used to treat complex intracranial aneurysms including wide-neck and fusiform aneurysms. Balloon angioplasty has been used to better appose the flow diverter (FD) to the vessel wall and, thus, improve aneurysm occlusion rates and decrease periprocedural complications. Sparse data are available concerning the results of this technique. We report our experience with silk + FD associated with balloon angioplasty for the treatment of intracranial aneurysms.

Methods

A retrospective study was conducted on all patients treated by the silk + FD. Clinical charts, procedural data, and angiographic results were reviewed and compared between those treated with balloon angioplasty. A multivariate analysis was conducted to identify predictors of complications, occlusion, and outcome.

Results

Between July 2014 and May 2016, we identified 209 patients with 223 intracranial aneurysms. There were 176 (84.2%) women and 33 (15.8%) men. The most common stent size used was 4.5 mm in 101 patients (46.1%), followed by 4 mm in 57 patients (26%). Univariate analysis observed that stent diameter was significantly related to aneurysm occlusion (P < 0.05). Patients with more than 1 aneurysm treated with silk + stent have a 9.07 times greater chance of having complications in the procedure than patients with only 01 aneurysm (OR = 9.07; P = 0.0008). Patients who had angioplasty without the use of a balloon have a 13.69-times-higher risk of complications (OR = 13.69; P = 0.0003). Older age, larger aneurysms, and the use of more than 1 FD device were predictors of recanalization.

Conclusion

Endovascular treatment of intracranial aneurysms with the silk + FD associated with balloon angioplasty is a safe and effective therapeutic option. Balloon angioplasty in combination with FD lowers the risk of complications. Higher complication rates and worse outcomes are associated with older age and large 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.

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.

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.

Horizontal stent deployment via extracranial-intracranial bypass in coil embolization of basilar apex aneurysms: technical report

BACKGROUND

The endovascular treatment of large, wide-necked basilar apex aneurysms (BAAs) remains challenging. Although horizontal stent deployment across both P1 segments of the posterior cerebral arteries (PCAs) would be an optimal strategy in coil embolization of wide-necked BAAs, this is only feasible in cases with anatomically favorable access. In rare circumstances, large-diameter conduits of extracranial-intracranial (EC-IC) bypass can also provide a good access route for endovascular treatment of complex intracranial aneurysms.

METHODS

We describe the technique of accessing the PCA via EC-IC bypass grafts and deploying a stent horizontally across the neck of BAA and its coil embolization. We provide a detailed technical review and describe some pitfalls of the procedure.

RESULTS

Two patients underwent EC-IC bypass surgery prior to the treatment of a large, wide-necked BAA. The radial artery and saphenous vein were used as grafts, respectively. To facilitate coil embolization for a large BAA, a PCA-to-PCA horizontal stent was deployed via the bypass graft. Trans-cell and jailing techniques were used, respectively. Both aneurysms were completely occluded, and the patients were discharged without any neurological deficit.

CONCLUSION

Horizontal stent deployment via EC-IC bypass grafts can be performed safely, providing proper closure of the aneurysmal neck and apposition to both PCAs, facilitating complete coil embolization.

A comparison between the CS-TOF and the CTA/DSA for WEB device management

PURPOSE

There is no study on the role of three-dimensional compressed sensing time of flight MR angiography (3D-CS-TOF) in the management of the WEB device. We evaluated the efficacy of 3-tesla 3D-CS-TOF for the management and follow-up of the WEB device implantations.

MATERIALS AND METHODS

Seventy-three aneurysms of 69 patients treated with the WEB device were retrospectively examined. Morphological parameters and embolization results of the aneurysms were assessed and compared on 3D-CS-TOF, CTA, and DSA images.

RESULTS

Occluded, neck remnant, and recurrent aneurysms were observed in 61 (83.6%), 7 (9.6%), and 5 (6.8%) aneurysms, respectively. Inter- and intra-reader agreement values related to aneurysm size measurements were perfect. Aneurysms size, age, and proximal vessel tortuosity were negatively correlated with the visibility of the aneurysms and parent vessels on 3D-CS-TOF images (p = 0.043; p = 0.032; p < 0.001, respectively). Subarachnoid hemorrhage and age are associated with 3D-CS-TOF artifacts (p = 0.031; p = 0.005, respectively). 3D-CS-TOF findings are in perfect agreement with DSA or CT angiography (CTA) results (p < 0.001).

CONCLUSION

According to our results, 3D-CS-TOF can be an easy, fast, and reliable alternative for the management or follow-up of WEB assisted embolization.

Long-Term Outcomes of Placement of a Single Transverse Stent through the Anterior Communicating Artery via the Nondominant A1 in Coil Embolization of Wide-Necked Anterior Communicating Artery Aneurysms

Objective

Placement of a single transverse stent via the nondominant A1 across the anterior communicating artery (AComA) into the contralateral A2 can provide sufficient neck coverage for wide-necked bifurcation AComA aneurysms. The authors described the feasibility, safety and long-term outcomes of this technique.

Methods

Between January 2015 and February 2018, placement of a single transverse stent via the nondominant A1 was attempted in 17 wide-necked bifurcation AComA aneurysms. The authors reviewed the medical records and radiological studies.

Results

The technical success rate was 94.1% (16/17). Periprocedural thromboembolic complications occurred in one patient (6.3%) without permanent neurological deficits. The mean clinical follow-up duration was 39.9±9.8 months. No deaths or delayed thromboembolic complications occurred. The mean angiographic follow-up duration was 38.9±9.8 months. The immediate and final follow-up complete occlusion rates were 87.4 and 93.7%, respectively. There was no recanalization during the follow-up period.

Conclusion

Placement of a single transverse stent via the nondominant A1 across the AComA into the contralateral A2 is a feasible and relatively safe endovascular technique for the treatment of wide-necked bifurcation AComA aneurysms, with good long-term occlusion rates and a reasonable complication rate, if only the nondominant A1 is applicable.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

WEB Device Shape Changes in Elastase-Induced Aneurysms in Rabbits

BACKGROUND AND PURPOSE

While WEB devices have been shown to be safe and effective for aneurysm treatment, WEB-shape modification compression has been associated with incomplete aneurysm occlusion. We explored the relationship between occlusion rates and WEB-shape modification in different WEB device types in an experimental aneurysm model.

MATERIALS AND METHODS

Elastase-induced aneurysms were created in rabbits and treated with dual-layer (n = 12), single-layer (n = 12), or single-layer sphere (n = 12) WEB devices. Aneurysms were followed up either at 3 or 12 months. Angiographic occlusion was graded using the WEB Occlusion Scale: grade I, complete; grade II, complete but recess filling; grade III, residual neck; or grade IV, residual aneurysm. WEB-shape modification and histologic features were also analyzed.

RESULTS

Grade I or II occlusion was seen in 16 (44%) aneurysms, and grade I, II, or III ("adequate") occlusion was observed in 22 (61.1%) aneurysms at follow-up. WEB-shape modification was observed in 22 (61.1%) aneurysms. WEB-shape modification was higher in single-layer (9/12) and dual-layer (10/12) devices compared with single-layer sphere devices (3/12). Aneurysms with WEB-shape modification had a higher level of thrombus organization in the dome compared with those without WEB-shape modification (68% [15/22] versus 50% [7/14]). WEB-shape modification was not correlated with angiographic or histologic outcomes but was significantly correlated with levels of fibrosis and smooth muscle cells in the aneurysm.

CONCLUSIONS

WEB-shape modification is not associated with incomplete aneurysm occlusion of WEB devices in the rabbit model but may be related to connective tissue formation and the healing response to WEB device implantation.

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.

The Exchange-Free Technique: A Novel Technique for Enhancing Surpass Flow Diverter Placement

Background:

Following flow diverter placement, approximately 20% of intracranial aneurysms remain as residual aneurysms at 1 year. Device malapposition is a cause of residual aneurysms after flow diversion. We present a new and straightforward technique (exchange-free technique [EFT]) to enhance apposition of the surpass flow diverter (SFD), the only over-the-wire flow diverter currently available.

Materials and Methods:

We deployed laser-cut mini stents through the inner deployment catheter of the SFD. This maneuver was performed simply by withdrawing the micro-guidewire from its lumen and replacing it with a mini-stent (stents deliverable through microcatheters with inner diameter of 0.0165 inches), without a need to re-cross the deployed SFD or an exchange maneuver. All aneurysms in which this technique was utilized were retrospectively reviewed.

Results:

Twenty-eight patients (20 females) with 30 treated aneurysms were identified. The mean aneurysm diameter was 10.2 ± 6.6 mm. Technical success rate was 96.6% (29/30 aneurysms). There was no mortality or permanent morbidity related to the procedures. Except for the patient treated for an iatrogenic, surgery-related internal carotid artery pseudoaneurysm who died secondary to consequences of multiple surgeries, no cases of mortality or permanent morbidity were noted. Complete aneurysm occlusion rates were 78.2%, 82.1%, and 95.2% at 0–3, 3–6, and 9–12 months, respectively. None of the patients were re-treated.

Conclusion:

EFT is a simple and fast technique which was not associated with adverse effects in our series. The higher aneurysm obliteration rate obtained with EFT is probably the result of better wall apposition of the SFD.

Treatment of Ruptured and Unruptured Intracranial Aneurysms with WEB 17 Versus WEB 21 Systems : Comparison of Indications and Early Angiographic Outcomes

BACKGROUND

The concept of intrasaccular flow diversion using the Woven EndoBridge (WEB) device changed the traditional endovascular concept for wide-necked bifurcation aneurysms. The latest technical advancement resulted in the WEB 17 system, a softer device composed of fewer wires which enables treatment of smaller more distally located aneurysms by using smaller microcatheters as compared to the WEB 21 system.

OBJECTIVE

This retrospective observational study aimed to evaluate and compare the angiographic and clinical results achieved with WEB 21 and WEB 17 in aneurysm morphologies eligible for both systems (maximum width 3-6 mm).

METHODS

Between August 2014 and August 2019 a total of 63 and 130 aneurysms with a maximum width of 3-6 mm were treated with either WEB 21 and WEB 17, respectively, at 2 neurovascular centers. Cases were analyzed based on a comparison regarding aneurysm size, location and rupture status.

RESULTS

The technical success, the periprocedural complication rate and the rate of additional devices used showed no relevant differences between the two groups. Aneurysms treated with the WEB 17 system were smaller and more frequently distally located. The overall complete occlusion rate at 3 months was higher in the WEB 17 group (65.5% versus 55.1%). The superiority of complete aneurysm occlusion achieved with WEB 17 was statistically significant in the subgroup of unruptured middle cerebral artery aneurysms.

CONCLUSION

The use of WEB 17 expands the treatment indications for intrasaccular flow-diversion towards smaller and more distally located aneurysms with a safety profile comparable with that of the WEB 21.

Treatment of Acutely Ruptured Cerebral Aneurysms With the Woven EndoBridge Device: Experience Post-FDA Approval

BACKGROUND

Coil embolization of ruptured bifurcation aneurysms is challenging and often necessitates adjunctive stenting, which requires antiplatelet therapy in the setting of subarachnoid hemorrhage (SAH). The Woven EndoBridge (WEB; Terumo) device is an alternative self-expanding 3D mesh that does not require antiplatelet agents. However, its use has been mostly reserved for unruptured aneurysms.

OBJECTIVE

To assess the safety and feasibility of ruptured aneurysm treatment with the WEB.

METHODS

Retrospective analysis of 9 SAH patients with 11 aneurysms that were treated with the WEB device at 2 institutions after FDA approval.

RESULTS

Hunt and Hess grades were III and IV in 4 (44%) each and V in 1 (11%). All patients were treated within 24 h of hospitalization, and a single WEB was used in all but one aneurysm. Aneurysms treated were 3 basilar tip, 2 anterior communicating artery, 2 posterior inferior cerebellarartery, 1 middle cerebral artery, 1 carotid-ophthalmic artery, 1 posterior communicating artery, and 1 vertebrobasilar junction. Mean aneurysm height and width were 6.2 ± 2.2 mm (range: 3-10) and 5.6 ± 3.0 mm (range: 3.3-14), respectively. Mean dome-to-neck ratio was 1.7 ± 0.8 (range: 1.0-3.8). There was one intraoperative rupture that occurred because of device dislodgement and was managed with embolization. There were no treatment-related mortalities and no re-rupture after securement of the aneurysms with the WEB.

CONCLUSION

Our preliminary experience indicates that the WEB device can be used safely for ruptured aneurysms of various sizes in the anterior and posterior circulation. Larger series with long-term follow-up are necessary to confirm our findings.

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.

Flow-T stenting with the Silk Vista Baby and Baby Leo stents for bifurcation aneurysms - A novel endovascular technique

We present the first case using a novel flow diverter, the Silk Vista Baby (Balt, Montmorency, France), in combination with a low-profile braided stent, the Baby Leo (Balt, Montmorency, France), in a T configuration that we term Flow-T. We describe the technical characteristics of the case as well as the early follow-up results. We believe that this combination may provide an alternative to standard T-stenting and alternative to treat bifurcation aneurysms.

The Contour-Early Human Experience of a Novel Aneurysm Occlusion Device

BACKGROUND AND PURPOSE

Endosaccular flow disruption is a recognized treatment options for treating both unruptured and ruptured aneurysms. The Contour device is designed to target the neck of an aneurysm and cause flow disruption within the aneurysm hence promoting thrombosis and neo-endothelialization at the neck. This article presents initial experiences with the Contour.

METHODS

The prospectively maintained database was retrospectively reviewed to identify patients treated with the Contour device. Demographic data, aneurysm characteristics, clinical result, and clinical and radiological follow-up information were recorded.

RESULTS

The review identified 3 patients (2 female), with 3 unruptured aneurysms, of average age 67 ± 8.7 years (range 62-77 years). The aneurysms were all located in the anterior circulation including one pericallosal, one at the A1-2 junction and one on the ICA bifurcation. The mean average dome height was 7.6 ± 0.62 mm (range 7.1-8.3 mm), dome width 5.7 ± 2 mm (range 3.5-7.5 mm), and neck width 3.6 ± 0.95 mm (range 2.5-4.2 mm). At follow-up angiography two of the aneurysms were completely occluded and one device had displaced into the aneurysm sac due to inappropriate positioning of the device. Of the patients one had minor stroke during the postoperative period but returned to baseline neurology. All patients were mRS 0 at last follow-up.

CONCLUSION

The Contour is a promising new aneurysm occlusion device. Further studies with longer term follow-up are required to determine the efficacy of this novel device.

The RISE trial: A Randomized Trial on Intra-Saccular Endobridge devices

BACKGROUND

Wide-necked bifurcation aneurysms (WNBA) are a difficult subset of aneurysms to successfully repair endovascularly, and a number of treatment adjuncts have been designed to improve on the results of coiling, including stenting and flow diversion of the parent vessel. Surgical clipping is commonly performed for certain WNBAs, such as middle cerebral aneurysms, in some centres. Intra-saccular flow diversion (ISFD) using the Woven Endo-Bridge (WEB) or similar devices, has been developed as a new endovascular alternative to coiling for WNBAs. Meta-analyses of case series suggest satisfactory results, both in terms of safety and efficacy, but in the absence of randomized evidence, whether ISFD leads to better outcomes for patients with WNBA remains unknown. There is a need to offer ISFD within the context of a randomized care trial.

METHODS

The proposed trial is a multicentre, randomized controlled care trial comparing ISFD and best conventional management option (surgical or endovascular), as determined by the treating physician prior to randomized allocation. At least 250 patients will be recruited in at least 10 centres over a four-year period, and followed for one year, to show that ISFD can increase the incidence of successful therapy from 75 to 90% of patients, defined as complete or near-complete occlusion of the aneurysm AND a good clinical outcome (mRS ≤ 2) at one year. The trial will be followed by an independent data safety monitoring committee to assure the safety of participants.

CONCLUSION

Introduction of intra-saccular flow diversion can be accomplished within a care trial context.

Placement of a Stent within a Flow Diverter Improves Aneurysm Occlusion Rates

BACKGROUND AND PURPOSE

Placement of a stent within a flow diverter has been described previously but its consequences have not been analyzed. We evaluated the clinical and angiographic results of stent placement within a flow diverter during the same treatment session.

MATERIALS AND METHODS

All patients treated with a Surpass flow diverter were retrospectively evaluated. Patients with previously deployed stents and procedures in which scaffolding stents, a second flow diverter, or intrasaccular devices were used were excluded. Patient and aneurysm characteristics and clinical and imaging follow-up results were compared between stented and nonstented Surpass flow-diverter groups and stent assisted coiling.

RESULTS

Thirty-five patients (41 aneurysms) were treated with a Surpass flow diverter only (monotherapy group), and in 33 patients (35 aneurysms), a stent was placed within the Surpass flow diverter (stented group). Stents were placed inside the Surpass flow diverter for a variety of reasons at the operator's discretion. No statistical difference was noted between the 2 groups in age, body weight, sex, history of thromboembolic events, smoking, platelet inhibition levels, hypertension, hyperlipidemia, diabetes mellitus, malignancy, and aneurysm location. Aneurysms in the stented group were larger than those in the monotherapy group (14.8 versus 9.1 mm, P < .001). The rate of clinically significant adverse events and complete aneurysm occlusion rates at 0-3 and 3-6 months (73.3% versus 61.3%, P = .31, and 84.8% versus 70.2%, P = .14) were similar. At 9-12 months, a significantly higher proportion of aneurysms in the stented group achieved complete occlusion (93.9% versus 73.2%, P = .019). There was a trend toward a higher obliteration rate on final follow-up in the stented group (93.9% versus 82.9%, P = .14).

CONCLUSIONS

Placement of a stent within a flow diverter increases the rate of aneurysm occlusion. We propose that these results are from improved flow-diverter apposition due to the higher radial force of intracranial stents.

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.

Treatment of Wide-Neck Intracranial Aneurysms with the Woven EndoBridge Device Associated with Stenting: A Single-Center Experience

BACKGROUND AND PURPOSE

The intrasaccular flow disruptor, the Woven EndoBridge device, is increasingly used for the treatment of wide-neck intracranial aneurysms. Due to unfavorable anatomy, additional stent placement is sometimes required to avoid Woven EndoBridge protrusion into bifurcation branches. We report our experience with the Woven EndoBridge associated with stent placement for the treatment of complex intracranial aneurysms.

MATERIALS AND METHODS

Patients with aneurysms treated with the Woven EndoBridge Single-Layer plus stent placement were evaluated retrospectively with prospectively maintained data. The technical feasibility, procedural complications, aneurysm occlusion, and clinical outcome were studied.

RESULTS

Seventeen patients and aneurysms treated with the Woven EndoBridge plus stent placement were included. The mean aneurysm size was 7 ± 3.1 mm. Aneurysm locations were the following: MCA (10 patients), anterior communicating artery (3 patients), basilar tip (3 patients), and posterior communicating artery (1 patient). Two lesions were ruptured and treated in the acute phase. The Woven EndoBridge and stent placement were successfully delivered in all cases. There were no permanent/major complications. Among the 2 patients with SAH, minor and completely reversible in-stent thrombosis occurred during treatment. An asymptomatic occlusion of the angular artery with a distal nonbifurcation aneurysm was discovered during the angiographic follow-up. Long-term (10.4 months) angiographic complete (Raymond-Roy I) and near-complete (Raymond-Roy II) occlusion was obtained in 11 (69%) and 2 (12.5%) aneurysms, respectively. The mean sizes of aneurysms showing Raymond-Roy I/Raymond-Roy II and Raymond-Roy III occlusion were 5.5 ± 2.1 mm and 10 ± 1 mm, respectively (P = .003). The mean fluoroscopy time was 35 ± 14 minutes.

CONCLUSIONS

Aneurysm embolization with the Woven EndoBridge device associated with stent placement appears technically feasible and effective for the treatment of lesions with unfavorable anatomy. In our study, this strategy was relatively safe with a low rate of relevant procedure-related adverse events.

Treatment of Wide-Necked Bifurcation Aneurysms : Initial Results with the pCANvas Neck Bridging Device

Background

Recently, numerous devices dedicated to the treatment of wide-necked aneurysms have become available. We present our initial experience with the pCANvas device and present the technical success rate, clinical outcome and immediate angiographic occlusion rates.

Objective

We sought to determine the efficacy of flow with the pCANvas for the treatment of unruptured intracranial aneurysms.

Methods

We performed a retrospective review of our prospectively collected data to identify patients treated with the pCANvas device between February 2015 and February 2017. The patient demographics, aneurysm characteristics, immediate and delayed clinical and radiographic follow-up data were recorded.

Results

We identified 17 patients (13 female) treated only with the pCANvas device. The average age of the patients was 60.5 ± 13.3 years (range 25–75 years). The average dome width was 7.6 ± 3.2 mm (range 3–15.8 mm), dome height 7.1 ± 3.2 mm (range 3–12.9 mm) and neck width 5.4 ± 3.2 (range 3–16.3 mm). The average aspect ratio was 1.5 ± 0.8 (range 0.6–3.7). At the end of the procedure 15 aneurysms continued complete filling of the aneurysm (Raymond Roy Classification[RRC] 3) with 2 aneurysms showing only filling of the neck of the aneurysm (RRC 2). Early follow-up angiography was available for 16 patients and at this stage 11 aneurysms showed persistent and complete filling of the aneurysm (RRC 3), 5 aneurysms showed complete occlusion of the aneurysm (RRC 1) and 7 aneurysms underwent repeat treatment with coiling.

Conclusion

The early results on the use of the pCANvas are promising; however, longer term follow-up and larger studies are required.

Systematic Review of Woven EndoBridge for Wide-Necked Bifurcation Aneurysms: Complications, Adequate Occlusion Rate, Morbidity, and Mortality

BACKGROUND

Although the Woven EndoBridge (WEB [Sequent Medical, Aliso Viejo, California, USA]) is a highly innovative technique for the endovascular treatment of wide-necked bifurcation aneurysms (WNBAs), there are no studies available comparing this technique with surgical results or other endovascular results of stent-assisted coiling or balloon-assisted coiling for WNBAs. The purpose of this study was to assess complications, complete occlusion rate, and morbidity and mortality of the WEB in WNBA treatment.

METHODS

Published literature citing embolization results for WNBAs using the WEB was reviewed. A systematic review was performed to evaluate the complications, complete occlusion rate, and morbidity and mortality.

RESULTS

We identified 19 studies, including 935 patients. The most frequent aneurysm locations were the bifurcation of the middle cerebral artery (MCA) (42.8%), the anterior communicating artery (23%), and the basilar bifurcation (20.8%). The technical success rate of the WEB was 97% (95% confidence interval [CI], 96%-98%). The thromboembolic complication rate was 8% (95% CI, 6%-11%). The thromboembolic complication rate was 10% (95% CI, 7%-13%) in cases before 2013, which was higher than in cases after 2013 (6%; 95% CI, 4%-9%; P = 0.045). MCA bifurcation aneurysm has a higher thromboembolic complication rate than posterior circulation aneurysm. The overall bleeding complication rate of the WEB was 2% (95% CI, 1%-3%). The adequate occlusion rate was 81% (95% CI, 76%-85%). Morbidity during follow-up was 3% (95% CI, 1%-4%) (I2 = 30.4%), and mortality was 2% (95% CI, 1%-3%).

CONCLUSIONS

Adequate aneurysm occlusion was found in 81% of WEB cases with low morbidity and mortality.

Two-Center Experience in the Endovascular Treatment of Ruptured and Unruptured Intracranial Aneurysms Using the WEB Device: A Retrospective Analysis

BACKGROUND AND PURPOSE

The safety and efficacy of the Woven EndoBridge (WEB) device for the treatment of cerebral aneurysms has been investigated in several studies. Our objective was to report the experience of 2 neurovascular centers with the WEB device in the treatment of broad-based intracranial aneurysms, including the technical feasibility and safety as well as short- and midterm angiographic and clinical follow-up-results.

MATERIALS AND METHODS

We performed a retrospective analysis of all ruptured and unruptured aneurysms treated with a WEB device (WEB Single-Layer and Single-Layer Sphere) between August 2014 and February 2017. Primary outcome measures included the feasibility of implantation and the angiographic outcome. Secondary outcome measures included the clinical outcome at discharge and procedural complications.

RESULTS

One hundred two aneurysms in 101 patients, including 37 (36.3%) ruptured aneurysms, were treated with the WEB device. Implantation was successful in 98 (96.1%) aneurysms. Additional devices (stents/coils) were necessary in 15.3% (15/98) of aneurysms. Procedural complications occurred in 4.9% (5/102). Of these, 4 were thromboembolic events and 1 was an intraprocedural rupture. Angiographic follow-up at 3 and 12 months was available for 79.6% (78/98) and 50.0% (49/98) of all aneurysms to date, respectively, showing a sufficient aneurysm occlusion in 80.7% (63/78) at 3 months and 77.6% (38/49) at 12 months. Delayed aneurysm ruptures have not been observed during the follow-up period to date.

CONCLUSIONS

The WEB device offers a safe and effective treatment option for broad-based intracranial aneurysms without the need for dual antiplatelet therapy.

Innovation in neurosurgery: less than IDEAL? A systematic review

BACKGROUND

Surgical innovation is different from the introduction of novel pharmaceuticals. To help address this, in 2009 the IDEAL Collaboration (Idea, Development, Exploration, Assessment, Long-term follow-up) introduced the five-stage framework for surgical innovation. To evaluate the framework feasibility for novel neurosurgical procedure introduction, two innovative surgical procedures were examined: the endoscopic endonasal approach for skull base meningiomas (EEMS) and the WovenEndobridge (WEB device) for endovascular treatment of intracranial aneurysms.

METHODS

The published literature on EEMS and WEB devices was systematically reviewed. Identified studies were classified according to the IDEAL framework stage. Next, studies were evaluated for possible categorization according to the IDEAL framework.

RESULTS

Five hundred seventy-six papers describing EEMS were identified of which 26 papers were included. No prospective studies were identified, and no studies reported on ethical approval or patient informed consent for the innovative procedure. Therefore, no clinical studies could be categorized according to the IDEAL Framework. For WEB devices, 6229 articles were screened of which 21 were included. In contrast to EEMS, two studies were categorized as 2a and two as 2b.

CONCLUSION

The results of this systematic review demonstrate that both EEMS and WEB devices were not introduced according to the (later developed in the case of EEMS) IDEAL framework. Elements of the framework such as informed consent, ethical approval, and rigorous outcomes reporting are important and could serve to improve the quality of neurosurgical research. Alternative study designs and the use of big data could be useful modifications of the IDEAL framework for innovation in neurosurgery.

Endovascular Treatment of Unruptured Intracranial Aneurysms by the Woven EndoBridge Device (WEB): Are There Any Aspects Influencing Aneurysm Occlusion?

BACKGROUND

The experience with Woven EndoBridge (WEB) device is still limited. The aim of this study is to discuss the efficacy of this new device, focusing on any anatomical and procedural factors influencing aneurysm occlusion.

METHODS

Between October 2011 and November 2016, 24 patients (10 female, 14 male) harboring 24 cerebral aneurysms treated with WEB in a single center were retrospectively reviewed. Patients underwent 6-month and 12- to 24-month (median 18 months) clinical and neuroradiologic follow-up. We evaluated whether any procedural or anatomical aspect influenced the occlusion rate.

RESULTS

Adequate occlusion (AO) was achieved in 68% of cases at 6 months' and in 87% at 18 months' follow-up respectively. Technical difficulties occurred in 3 procedures (12.5%). No postprocedural morbidity was reported. One patient (4%) died after 1 month for reasons unrelated to the procedure. Neck size and dome-to-neck ratio were significantly associated with aneurysm occlusion (P < 0.05). AO was not associated with postoperative dual antiplatelet therapy (P > 0.99) or device compression at both first and second follow-up (P > 0.99). Immediate contrast agent stagnation was more common in aneurysms that were occluded at first (P = 0.37) and second follow-up (P = 0.24), but statistical significance was not reached.

CONCLUSIONS

Endovascular treatment with WEB is a safe treatment for unruptured cerebral aneurysms, also resulting in a good AO rate in aneurysms that would otherwise require complex assisted coiling techniques. However, results are less favorable in cases of very large aneurysmal neck. Nevertheless, further series with larger patient populations and longer follow-up will define the role of WEB in the treatment of aneurysms.

The Use of Single Stent-Assisted Coiling in Treatment of Bifurcation Aneurysms: A Multicenter Cohort Study With Proposal of a Scoring System to Predict Complete Occlusion

BACKGROUND

The development of stent-assisted coiling has allowed for the endovascular treatment of wide-necked bifurcation aneurysms. A variety of options exist, and little is known about the optimal stent configuration in this setting. We report a large multicenter experience of stent-assisted coiling of bifurcations aneurysms using a single stent, with attention to factors predisposing to aneurysm recanalization.

OBJECTIVE

To assess the safety and efficacy of single stent-assisted coiling, in addition to analyzing the factors associated with recanalization, and proposal of a predictive scoring scale.

METHODS

A multicenter retrospective analysis of bifurcation aneurysms treated with a single stent-assisted coiling technique between 2007 and 2015 was performed. Clinical and radiographic data were collected and used to develop a scoring system to predict aneurysm occlusion.

RESULTS

A total of 74 bifurcation aneurysms were treated with single stent-assisted coiling. At a median follow-up of 15.2 mo, complete occlusion or remnant neck was achieved in 90.6% of aneurysms. Aneurysm location, maximal diameter, neck size, and alpha angle were predictive of aneurysm occlusion at last follow-up. A scoring system to predict complete occlusion based on these factors was developed. An increasing score correlated with a higher rate of complete occlusion.

CONCLUSION

The treatment of bifurcation aneurysm using single stent technique for stent-assisted coiling is safe and effective. Complete occlusion or remnant neck occlusion was achieved in 90.6% of cases. Class III aneurysms can be effectively treated using a single stent, while class I may require Y-stent technique.

The Woven Endobridge Device for Treatment of Intracranial Aneurysms: A Systematic Review

INTRODUCTION

The Woven Endobridge (WEB) device is an innovative endovascular device for treatment of intracranial aneurysms, especially bifurcation and wide-neck aneurysms. Although not approved by the U.S. Food and Drug Administration, it has been available in Europe since 2011. The aim of this review is to evaluate the outcomes of WEB device use for intracranial aneurysm treatment.

METHODS

A systematic review was conducted with MEDLINE search engines PubMed and Embase from 2011. The search strategy provided 6229 articles, and 19 articles were included.

RESULTS

A total of 19 papers were identified describing the use of WEB devices in 687 patients with 718 aneurysms. The 2 largest prospective multicenter studies (WEBCAST and the French Observatory Trial) reported successful treatment, defined as complete closure or a neck remnant, in 85% and 79% of aneurysms, respectively. The use of a WEB device in combination with coiling or stenting was described with varying results in multiple small series. Outcomes of WEB device use in ruptured aneurysms in 2 studies showed 94% and 80% adequate treatment. Thromboembolic events were described in 71 patients (10.3% of all patients) and infarctions in 8 patients (1.2% of all patients).

CONCLUSIONS

Despite initial promising results, the WEB device should be used with caution given its potentially large learning curve and because it has primarily been investigated only in wide-neck and bifurcation aneurysms. In addition, currently available prospective studies have short follow-up, and the device has not been directly compared with other treatment modalities.

Utility of crankshaft clips for middle cerebral artery aneurysms: A single-center experience of 150 cases

Background:

Applying more than one clip for a complicated-shaped aneurysm is an established strategy, particularly for middle cerebral arteries (MCA). However, obliterating the cleft of the internal elastic lamina with a single clip is theoretically possible because the line is usually on a single plane. Crankshaft clips were reformed for that purpose decades ago, but are not widely used and have been described in almost no report ever since.

Methods:

To reconsider and describe the utility of crankshaft clips for complicated MCA aneurysms and to articulate the advantages and limitations of the clips, we meticulously analyzed a series of more than 150 cases in which the crankshaft clips were used, predominantly for treatment of MCA aneurysms, at Moriyama Memorial Hospital between August 2010 and December 2015.

Results:

Readjustment of the clip was not necessary in almost all cases, and the first application was the final one. None of the patients had morbidity or mortality related to the surgical technique. To date, we have not experienced any trouble or recurrence.

Conclusions:

Crankshaft clips are useful and safe for clipping of complicated MCA aneurysms.

Efficacy and Safety of the Woven EndoBridge (WEB) Device for the Treatment of Intracranial Aneurysms: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

Intrasaccular flow diverters are increasingly being used in the treatment of wide-neck and bifurcation aneurysms. We performed a systematic review and meta-analysis of existing literature on the Woven EndoBridge device in the treatment of intracranial aneurysms.

MATERIALS AND METHODS

A comprehensive literature search was performed through October 1, 2015. We extracted information on baseline aneurysm and patient characteristics. Outcomes studied included immediate and midterm (>3 month) angiographic outcomes (complete occlusion as well as adequate occlusion, defined as complete occlusion or neck remnant), aneurysm retreatment, intraoperative rupture, perioperative morbidity and mortality, thromboembolic complications, and treatment failure. Meta-analysis was performed by using the random-effects model.

RESULTS

Fifteen uncontrolled series were included in this analysis, including 565 patients with 588 aneurysms, of which 127 were ruptured. Initial complete and adequate occlusion rates were 27% (95% CI, 15%-39%) and 59% (95% CI, 39%-78%), respectively. Midterm complete and adequate occlusion rates after a median of 7 months were 39% (95% CI, 26%-52%) and 85% (95% CI, 78%-91%), respectively. Perioperative morbidity and mortality rates were 4% (95% CI, 1%-8%) and 1% (95% CI, 0%-2%), respectively. Midterm adequate occlusion rates for ruptured aneurysms were 85% (95% CI, 67%-98%), compared with 84% (95% CI, 72%-94%) for unruptured aneurysms (P = .89). Patients with ruptured aneurysm had similar rates of perioperative morbidity to patients with unruptured aneurysm (2%; 95% CI, 0%-26% versus 2%; 95% CI, 0%-6%, respectively; P = .35).

CONCLUSIONS

Early evidence derived from uncontrolled studies suggests that Woven EndoBridge treatment has a good safety profile and promising rates of adequate occlusion, especially given the complexity of aneurysms treated. Further prospective clinical trials are needed to confirm these results and better define the risks and benefits of use of the Woven EndoBridge device in treating wide-neck and wide-neck bifurcation aneurysms.

The Medina Embolic Device: early clinical experience from a single center

Objective

To report our initial experience with the Medina Embolic Device (MED) in unruptured intracranial aneurysms either as sole treatment or in conjunction with additional devices.

Methods

15 consecutive patients (6 women, 9 men) with unruptured aneurysms were treated between September 2015 and April 2016. The aneurysm fundus measured at least 5 mm. We evaluated the angiographic appearances of treated aneurysms at the end of the procedure and at follow-up, the clinical status, complications, and requirement for adjunctive devices.

Results

The MED was successfully deployed in all but one case and adjunctive devices were required in 10 cases. Aneurysm locations were middle cerebral artery bifurcation (n=3), internal carotid artery (ICA) bifurcation (n=1), supraclinoid ICA (n=5), posterior communicating artery (n=1), anterior communicating artery (n=2), cavernous ICA (n=2), distal basilar sidewall (n=1), basilar tip (n=1). Three patients had complications although none could be attributed to the MED. Immediate angiographic results were modified Raymond-Roy classification (mRRC) I=1, mRRC II=5, mRRC IIIa=3, mRRC IIIb=5, and one patient showed contrast stasis within the fundus of the aneurysm. Follow-up angiography was available in 11 patients, with four showing complete aneurysm exclusion, six with stable remnants and one patient with an enlarging neck remnant.

Conclusions

The MED represents a major step forward in the treatment of intracranial aneurysms. It can result in rapid exclusion of an aneurysm from the circulation and has a good safety profile. We believe that the true value of the MED will be in combining its use with adjunctive devices such as endoluminal flow diverters that will result in rapid aneurysmal exclusion.