Current Evaluation of the Safety and Efficacy of Aneurysm Treatment with the WEB Device

Adjustment of Malpositioned Woven EndoBridge Device Using Gooseneck Snare: Complication Management Technique

The Woven EndoBridge (WEB) is an intrasaccular flow-disrupting device for the treatment of wide-necked saccular cerebral aneurysms. As with any neuroendovascular device, complications in the form of malpositioning and migration must be managed quickly and safely. Few studies have reported complication management techniques in instances of dislocated or migrated WEB devices. We retrospectively describe a case of a malpositioned WEB device that was successfully adjusted with the use of a gooseneck snare. Multiple other intra-procedural bailout strategies for management of WEB malposition and migration were considered, and are herein discussed. Operators should be aware of the causes of WEB malposition and a variety of bailout strategies.

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.

Clipping of recanalized intracerebral aneurysms initially treated by the Woven EndoBridge device

Background and purpose

Intrasaccular flow disruption using the Woven EndoBridge (WEB) is a safe and effective method to treat intracranial aneurysms, particularly wide neck bifurcation aneurysms. However mid term and long term follow-up imaging can show aneurysm remnant or recanalization, and retreatment is therefore sometimes necessary. In most cases, retreatment is performed using an endovascular approach. The present series reports and analyzes aneurysm clipping of recanalized or incompletely occluded aneurysms following WEB treatment.

Methods

All patients treated with the WEB device since the beginning of our experience in June 2011 were prospectively collected in a local database. Among them, patients who were retreated by clipping for aneurysm remnants were included in the present series.

Results

In the cumulative population of 130 patients with aneurysms treated by the WEB device from June 2011 to February 2019, 4 patients (3.1%) were retreated with surgical clipping due to incomplete occlusion (2 patients) and aneurysm recanalization (2 patients). Three of the four aneurysms retreated (75%) were located in the middle cerebral artery and one in the anterior communicating artery (25.0%). The aneurysm was ruptured in 1 of 4 patients (25%). Clipping was performed 10–54 months after initial treatment with the WEB. Surgical exposure showed that the WEB device was inside the aneurysm sac in all cases. Clipping was easily performed in all but 1 case. Control DSA showed complete occlusion in two aneurysms and a neck remnant in two.

Conclusion

Clipping is a feasible option for treating aneurysm remnants following initial treatment with intrasaccular flow disruption using the WEB.

Efficiency and complications of Woven EndoBridge (WEB) devices for treatment of larger, complex intracranial aneurysms-a single-center experience

BACKGROUND

Several recently published multicenter studies have reported high treatment feasibility, high safety, and good 6-month to 1-year efficiency when treating smaller intracranial aneurysms (IA) with WEB deployment. The purpose of the study was to evaluate the long-term efficiency and complications related to WEB treatment of larger, complex intracranial aneurysms in a small single-center cohort.

METHODS

Patients with ruptured and unruptured IA were treated with WEB devices; data were collected prospectively and analyzed retrospectively. The study evaluates complications and clinical and radiological findings at immediate and last available follow-up.

RESULTS

The study included 16 patients with 16 aneurysms and a median follow-up time of 36 months, range 13-49 months; 9/16 were females. Median age 59 with range 39-71 years. Mean aneurysm size 11.3 ± 1.7 mm, predominant location at the basilar artery bifurcation and anterior communicating artery. Three out of sixteen IAs were ruptured. Even though 75% of the IAs were immediately occluded completely, retreatment was eventually necessary in 7/15 (46.7%). Increasing neck remnants and recurrences were mainly observed past 1-year follow-up. The WEB device showed modifications over time, with six devices showing signs of compression in the long term. There was one fatality due to aneurysm rupture after 4 years.

CONCLUSIONS

The long-term efficiency of WEB deployment in larger, complex aneurysms is low with about half of the cases needing at least one retreatment. A large fraction of WEB collapse past 1-year follow-up.

Treatment of recurrent aneurysms using the Woven EndoBridge (WEB): anatomical and clinical results

Background

The safety and efficacy of the Woven EndoBridge (WEB) for the treatment of naïve intracranial aneurysms has been confirmed.

Purpose

To analyze the safety and efficacy of the WEB in the treatment of recurrent aneurysms.

Methods

Anatomical and clinical results in consecutive patients with a recurrent aneurysm, who were treated using the WEB device in two French neurointerventional centers, were evaluated.

Results

Seventeen patients with 17 aneurysms were included. Treatment was feasible in 16 patients. In seven patients (41.2%), ancillary devices were used. Permanent morbidity due to a thromboembolic complication occurred in one patient (5.9%). There was no mortality. Follow-up angiographic studies were available for 15 patients after a mean of 12.1±6.1 months. Rates of complete occlusion, neck remnant, and aneurysm remnant were 33.3%, 40.0%, and 26.7%, respectively.

Conclusions

Treatment of recurrent aneurysms using the WEB device may be reasonably safe and effective.

Physician training protocol within the WEB Intrasaccular Therapy (WEB-IT) study

INTRODUCTION

The WEB Intra-saccular Therapy (WEB-IT) trial is an investigational device exemption study to demonstrate the safety and effectiveness of the WEB device for the treatment of wide-neck bifurcation aneurysms. The neurovascular replicator (Vascular Simulations, Stony Brook, New York, USA) creates a physical environment that replicates patient-specific neurovascular anatomy and hemodynamic physiology, and allows devices to be implanted under fluoroscopic guidance.

OBJECTIVE

To report the results of a unique neurovascular replicator-based training program, which was incorporated into the WEB-IT study to optimize technical performance and patient safety.

METHODS

US investigators participated in a new training program that incorporated full surgical rehearsals on a neurovascular replicator. No roll-in cases were permitted within the trial. Custom replicas of patient-specific neurovascular anatomy were created for the initial cases treated at each center, as well as for cases expected to be challenging. On-site surgical rehearsals were performed before these procedures.

RESULTS

A total of 48 participating investigators at 25 US centers trained using the replicator. Sessions included centralized introductory training, on-site training, and patient-specific full surgical rehearsal. Fluoroscopy and procedure times in the WEB-IT study were not significantly different from those seen in two European trials where participating physicians had significant WEB procedure experience before study initiation.

CONCLUSIONS

A new program of neurovascular-replicator-based physician training was employed within the WEB-IT study. This represents a new methodology for education and training that may be an effective means to optimize technical success and patient safety during the introduction of a new technology.

Demographic, procedural and 30-day safety results from the WEB Intra-saccular Therapy Study (WEB-IT)

INTRODUCTION

The Woven EndoBridge (WEB) represents a novel intrasaccular therapeutic option for the treatment of intracranial wide-necked bifurcation aneurysms (WNBAs). The WEB-IT Study is a pivotal Investigational Device Exemption (IDE) study to determine the safety and effectiveness of the WEB device for the treatment of WNBAs located in the anterior and posterior intracranial circulations. We present the patient demographics, procedural characteristics, and 30-day adverse event data for the US WEB-IT study.

METHODS

WEB-IT is a prospective multicenter single-arm interventional study conducted at 25 US and 6 international centers. The study enrolled 150 adults with WNBAs of the anterior and posterior intracranial circulations. All patients were intended to receive a WEB device delivered via standard endovascular neurosurgical embolization techniques. The study was conducted under Good Clinical Practices and included independent adjudication effectiveness outcomes and all adverse events.

RESULTS

One hundred and fifty patients enrolled at 27 investigational sites underwent attempted treatment with the WEB. Mean age was 59 years (range 29-79) and 110 (73.3%) of the patients were female. Treated aneurysms were located at the basilar apex (n=59, 39.3%), middle cerebral artery bifurcation (n=45, 30%), anterior communicating artery (n=40, 26.7%), and internal carotid artery terminus (n=6, 4%). Average aneurysm size was 6.4 mm (range 3.6-11.4) with a mean neck size of 4.8 mm (range 2.0-8.2, mean dome to neck ratio 1.34). Nine patients presented with ruptured aneurysms. Of the enrolled patients, 98.7% were treated successfully with WEB devices. Mean±SD fluoroscopy time was 30.2±15.7 min. One primary safety event (PSE) (0.7%)-a delayed parenchymal hemorrhage 22 days after treatment-occurred between the index procedure and 30-day follow-up. In addition to the single PSE, there were seven (4.7%) minor ischemic strokes (5 resolved without sequelae and 2 had a modified Rankin Scale score of 1 at 30 days), five (2.7%) transient ischemic attacks, and two (1.3%) minor subarachnoid hemorrhages, which did not meet the prospectively established criteria for PSEs.

CONCLUSIONS

The WEB device can be used to treat WNBAs with a high level of procedural safety and a high degree of technical success.

TRIAL REGISTRATION NUMBER

NCT02191618; Pre-results.