Safety results from the treatment of 109 cerebral aneurysms using the Woven EndoBridge technique: preliminary results in the United Kingdom

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OBJECTIVE

The Woven Endobridge (WEB) device has been in clinical use for the treatment of brain aneurysms for the past 4 years. Observational studies to assess clinical outcome and related complications have been published. Clear evidence is required to better understand the safety profile of the WEB device. The authors here present a multicenter series that provides a detailed safety analysis focused on patient selection, procedural events, and technical issues of treated patients throughout the United Kingdom (UK).

METHODS

A nationwide password-protected database was set up to collect anonymous information across the UK (14 centers). Complications and clinical outcome were analyzed for the initial 109 patients (112 procedures). An independent root cause analysis classified the complications into groups (procedural, disease, device, ancillary device, and other). The modified Rankin Scale (mRS) was used as a marker of clinical outcome.

RESULTS

Each of the 109 patients had 1 aneurysm suitable for WEB treatment (109 aneurysms). Three patients had 2 procedures, making a total of 112 procedures performed. Eight procedures were abandoned because of access issues; 2 patients went on to have a successful procedure. All 109 patients had a preprocedure and discharge mRS scores recorded. One hundred patients had a recorded mRS score from a > 3-month follow-up.

Deployment of the WEB device was successful in 103 (94.5%) of 109 patients and 104 (92.9%) of 112 procedures. One patient had 2 successful WEB procedures on separate occasions. Patients without a successfully implanted WEB device were included in the analysis. Selection analysis showed that the average patient age was 56.5 years among 34 men and 75 women. The percentage of incidental aneurysms was 58.7%, acute 16.5%, symptomatic 18.3%, and recurrent 6.4%. Further results analysis showed that 40 (36.7%) of 109 patients had recorded adverse events, including those unrelated to the WEB device. Events that could be related to the WEB device numbered 17 (15.6%) among the 109 patients. Two patients with device-related complications were symptomatic. Overall, 11 patients (10.1%) had persistent clinical sequelae. Thromboembolism was the most prevalent event, affecting 15.6% of the patients (17 of 109), and 6.4% of the patients (7 of 109) with a thromboembolism were symptomatic.

Overall mortality before discharge was 0% and at the > 3-month follow-up was 5% (5 of 100 patients). Morbidity was defined as an mRS score increase to > 2. Overall morbidity at discharge was 1.8% (2 of 109) and at the > 3-month follow-up was 6% (6 of 100). No device-related morbidity or mortality was associated with this group.

CONCLUSIONS

The UK data show that the WEB device is safe for clinical use. Thromboembolic complication adds a risk that should be minimized with appropriate anticoagulation and correct sizing of the device. There is scope for further evaluation and standardization of an anticoagulation regimen for the WEB device.

ABBREVIATIONS DL = double layer; ISAT = International Subarachnoid Aneurysm Trial; MCA = middle cerebral artery; mRS = modified Rankin Scale; SAH = subarachnoid hemorrhage; SL = single layer; SLS = single-layer sphere; UK = United Kingdom; WEB = Woven EndoBridge.

OBJECTIVE

The Woven Endobridge (WEB) device has been in clinical use for the treatment of brain aneurysms for the past 4 years. Observational studies to assess clinical outcome and related complications have been published. Clear evidence is required to better understand the safety profile of the WEB device. The authors here present a multicenter series that provides a detailed safety analysis focused on patient selection, procedural events, and technical issues of treated patients throughout the United Kingdom (UK).

METHODS

A nationwide password-protected database was set up to collect anonymous information across the UK (14 centers). Complications and clinical outcome were analyzed for the initial 109 patients (112 procedures). An independent root cause analysis classified the complications into groups (procedural, disease, device, ancillary device, and other). The modified Rankin Scale (mRS) was used as a marker of clinical outcome.

RESULTS

Each of the 109 patients had 1 aneurysm suitable for WEB treatment (109 aneurysms). Three patients had 2 procedures, making a total of 112 procedures performed. Eight procedures were abandoned because of access issues; 2 patients went on to have a successful procedure. All 109 patients had a preprocedure and discharge mRS scores recorded. One hundred patients had a recorded mRS score from a > 3-month follow-up.

Deployment of the WEB device was successful in 103 (94.5%) of 109 patients and 104 (92.9%) of 112 procedures. One patient had 2 successful WEB procedures on separate occasions. Patients without a successfully implanted WEB device were included in the analysis. Selection analysis showed that the average patient age was 56.5 years among 34 men and 75 women. The percentage of incidental aneurysms was 58.7%, acute 16.5%, symptomatic 18.3%, and recurrent 6.4%. Further results analysis showed that 40 (36.7%) of 109 patients had recorded adverse events, including those unrelated to the WEB device. Events that could be related to the WEB device numbered 17 (15.6%) among the 109 patients. Two patients with device-related complications were symptomatic. Overall, 11 patients (10.1%) had persistent clinical sequelae. Thromboembolism was the most prevalent event, affecting 15.6% of the patients (17 of 109), and 6.4% of the patients (7 of 109) with a thromboembolism were symptomatic.

Overall mortality before discharge was 0% and at the > 3-month follow-up was 5% (5 of 100 patients). Morbidity was defined as an mRS score increase to > 2. Overall morbidity at discharge was 1.8% (2 of 109) and at the > 3-month follow-up was 6% (6 of 100). No device-related morbidity or mortality was associated with this group.

CONCLUSIONS

The UK data show that the WEB device is safe for clinical use. Thromboembolic complication adds a risk that should be minimized with appropriate anticoagulation and correct sizing of the device. There is scope for further evaluation and standardization of an anticoagulation regimen for the WEB device.

ABBREVIATIONS DL = double layer; ISAT = International Subarachnoid Aneurysm Trial; MCA = middle cerebral artery; mRS = modified Rankin Scale; SAH = subarachnoid hemorrhage; SL = single layer; SLS = single-layer sphere; UK = United Kingdom; WEB = Woven EndoBridge.

Endovascular detachable coil treatment has become the therapy of choice for most cerebral aneurysms since the introduction of the Guglielmi detachable coil in the 1990s.10,11 With the publication of the results of the International Subarachnoid Aneurysm Trial (ISAT) in 2002,17 endovascular coiling for ruptured brain aneurysms has become the mainstay of cerebral aneurysm treatment in Western Europe. The treatment has also been widely applied to unruptured cerebral aneurysms, resulting in an exponential increase in the pace of innovation in the field of interventional neuroradiology. Adjuncts that have been developed to assist the coiling include stents, balloon remodeling, and flow diverters.3,5,14,20

The Woven EndoBridge (WEB) device (Sequent Medical) provides a potential alternative to coiling as a treatment option for certain cerebral aneurysms, mainly wide-necked bifurcation aneurysms that present challenges for simple coiling. The WEB device is particularly suited to treating wide-necked aneurysms that are difficult to treat and have a high recurrence rate when treated with conventional coiling techniques. The device is a sphere of mixed-diameter nitinol wires braided to form a dense compliant mesh causing blood flow disruption and to create thrombosis and occlusion, thus preventing rupture. Currently, 3 generations of WEB device are in use (Fig. 1): the double layer (WEB DL), single layer (WEB SL), and single-layer sphere (WEB SLS). The WEB DL has a distal and a proximal layer of mesh and 3 radiopaque markers. The WEB SL and SLS each have only 1 layer of mesh and 2 radiopaque markers. The SLS differs from the SL in having a spherical shape and larger diameters. The proximal surface of the WEB device is concave to prevent thrombus. All WEB devices are sized by width and height. A handheld device uses electrothermal energy for deployment of the WEB device. All 3 types of the WEB device were included in this study and in our results.

FIG. 1.
FIG. 1.

A: A WEB DL device deployed from a catheter into a bifurcation aneurysm. B: A WEB SL device. C: A WEB SLS device. Copyright Sequent Medical. Published with permission. Figure is available in color online only.

Clinical use of the WEB device was first described in 2011.12 Because of the novelty of the device, its use has been reserved for selected patients who have limited alternative treatment options and expected technical difficulty with conventional coil embolization and/or clipping. The complications and clinical outcome with the WEB device must be studied to assess safety and clinical efficacy. In this study we used a national database to assess adverse events and clinical outcome in 109 consecutive patients to better understand the safety profile of this device.

Methods

Study Design

A national audit database was set up in September 2013 to audit safety information from all patients treated with a WEB device in the United Kingdom (UK; 14 centers). The database was password protected. Each center was able to enter its patient information. One hundred nine consecutive patients who underwent 112 procedures between March 2012 and March 2014 were entered into the database. The decision to use the WEB device was made based on various criteria at each center following a multidisciplinary meeting among clinicians. The criteria were related to aneurysm and aneurysm neck size, aneurysm location, and whether a neurosurgical option was available. Aneurysms suitable for standard coiling or clipping were excluded (unless patients refused the surgical option). Information was collected on clinical status according to the modified Rankin scale (mRS) both pre- and postprocedure. Procedural adverse events, technical events, and adjunctive device use were recorded. Data from up to March 2014 were collected retrospectively and from thereafter prospectively.

Technique

The general technique used to deliver the WEB device to the aneurysm has been described elsewhere.15,21 An 8-Fr guide sheath is placed in the main artery for navigation. A distal access catheter is often used for stability for delivering the device. Microcatheter selection is based on the size of the WEB device. The guidewire used was operator dependent, and subtle differences in the endovascular approach according to the operator were accepted but recorded in the database. All patients at all centers received an intraprocedural dose of intravenous heparin. Additional anticoagulation pre-, intra-, and postprocedure was given depending on the clinician and the case.

Adverse Event Analyses

Two independent interventional neuroradiologists (A.M. and R.S.) adjudicated the relationship of all reported adverse events and classified them into 5 categories: device related, procedure related, aneurysm disease related, ancillary device related, or related to another incidental condition. Data from the database were also categorized, and we found them to be in agreement with the adjudicated data.

Statistical Analyses

The statistical analysis was performed independently. The distributions of continuous variables were described using the means and standard deviations, and discrete variables were described as percentages. All statistical analyses were performed using the SPSS system, version 18.0.0 (SPSS Inc.).

Results

Baseline Characteristics of Patients and Aneurysms

One hundred nine patients underwent 112 consecutive procedures between March 2012 and March 2014 at 14 centers in the UK. The mean age of the patients was 56.5 years (SD 9.9 years). Each patient had 1 aneurysm determined to be suitable for WEB treatment (109 aneurysms). Two patients had 2 procedures given the failure of the first treatment, and 1 patient had a second WEB procedure because of a recurrence. Of the 109 patients, 103 (94.5%, 95% CI 88.4, 98.0) had a successful implant of the WEB device. Eight procedures were abandoned because of access issues; 2 patients went on to have a successful procedure. The procedure was elective in 91 patients (83.5%) and acute in 18 (16.5%). All aneurysms were saccular. Eight of the elective patients (7.3%) had partial thrombosis of the aneurysm. All 109 patients had a recorded preprocedure and discharge mRS score. One hundred patients had a follow-up mRS score from more than 3 months after the procedure.

Location of Aneurysms

Basilar aneurysms were the most common at 44 (40.4%) of 109, followed by middle cerebral artery (MCA) aneurysms at 39 (35.8%) of 109. The remaining aneurysms comprised those of the internal carotid artery (9 [8.2%] of 109), anterior communicating artery (8 [7.3%] of 109), posterior communicating artery (4 [3.7%] of 109), posterior cerebral artery (1 [1%] of 109), and anterior cerebral artery (4 [3.7%] of 109; Fig. 2). All patients had difficult to treat aneurysms that would not be suitable for unassisted coiling. Ninety-four aneurysms (86.2%) had a wide neck, 49 (45.0%) were bifurcation aneurysms, and 21 (19.3%) were not surgical candidates. Aneurysms were incidental in 64 patients (58.7%), 18 patients (16.5%) had acute subarachnoid hemorrhage (SAH), and 20 patients (18.3%) were symptomatic. Seven of the patients (6.4%) had recurrent aneurysms. The maximum aneurysm diameter ranged from 3.82 to 18.38 mm (mean 8.21 mm; Table 1). The maximum diameter of the aneurysm neck ranged from 2.35 to 11.42 mm (mean 6.18 mm).

FIG. 2.
FIG. 2.

Pie chart demonstrating the distribution of aneurysm locations. ACA = anterior cerebral artery; ACOM = anterior communicating artery; ICA = internal carotid artery; PCA = posterior cerebral artery; PCOM = posterior communicating artery. Figure is available in color online only.

TABLE 1.

Aneurysm characteristics

ParameterValue
Max aneurysm diameter in mm
  Mean (SD)8.21 (3.00)
  Max18.38
  Min3.82
Max neck diameter in mm
  Mean (SD)6.18 (1.77)
  Max11.42
  Min2.35
Max aneurysm diameter (%)*
  <7 mm33 (30.3)
  ≥7 to <10 mm47 (43.1)
  ≥10 mm29 (26.6)
Max neck diameter (%)*
  <4 mm1 (0.9)
  ≥4 mm108 (99.1)

Total of 109 aneurysms.

Treatment Analysis

One hundred three of the 109 patients (104 of 112 procedures) had successful deployment of the WEB device. One patient had 2 successful procedures on separate occasions. Fifty-seven procedures (54.8%) involved the WEB DL device; 11 of these procedures were acute and 46 were elective. Forty-one procedures (39.4%) involved the WEB SL device; 5 were acute and 36 were elective. Six procedures (5.8%) involved the WEB SLS device; 1 was acute and 5 were elective.

Safety Analysis

Inclusive of the abandoned procedures, 40 of the 109 patients had adverse events. Twenty-three of these events were unrelated to the WEB device. Recorded events included all minor events and technical events such as failed integrity test, alopecia, and disease or other events unrelated to the procedure or device. Eleven of these patients had persistent clinical symptoms related to an adverse event (Table 2), and 29 of the adverse events were without permanent clinical sequelae (Table 3). (Exclusive of abandoned procedures, 32 patients had recorded events. Nine of these patients had clinical symptoms [Table 2]. Twenty-three patients recovered with no new clinical symptoms [Table 3]). Presentation was classified as delayed if new symptoms developed after the first 3 months of follow-up and/or there was new radiographic evidence of an event at the > 3-month follow-up (with a previously normal followup scan with a modality of equal or greater sensitivity). The minimum follow-up for patients was more than 3 months, but 59 were followed up for more than 6 months and 14 of them were followed up for over a year (longest follow-up period 16 months).

TABLE 2.

Persistent clinical symptoms related to an adverse event in 11 patients who underwent WEB device placement

Case No.ComplicationsComplication CategoryWEB DeviceAcute or Elective ProcedurePretreatment mRS ScoreDischarge mRS ScoremRS Score at >3-Mo FUAdjuncts UsedDays From Procedure to EventRelated to WEB device?
1TE, vasospasmProcedureDLElective032No0No
2TEProcedureSLElective022Yes0No
3Rupture, TEDeviceDLElective001No0/21Yes
4Thrombo eventProcedureDLElective033No5No
5Delayed rupture, death (300 days)DiseaseDLElective006Yes300No
6Death (delayed rupture of different aneurysm)DiseaseDLElective006No336No
7Other (hydrocephalus, SAH, death)1st: disease, 2nd: disease1st: DL, 2nd: SLElective1st: 1, 2nd: 31st: 0, 2nd: 31st: 3, 2nd: 6No259No
8Parent vessel occlusion, TE, over-sized WEBDeviceDLElective011Yes0/0/0Yes
9Other (delayed thrombo event, death)AD (stent)DLElective006No279No
10Patient died due to comorbidities, access issue (abandoned)OtherDLElective106Yes306No
11Access issue, TE (abandoned)ProcedureDLElective111No
1st = first procedure; 2nd = second procedure; AD = ancillary device; FU = follow-up; TE = thromboembolism; thrombo = thromboembolic.
TABLE 3.

Adverse events without permanent clinical sequelae in 29 patients who underwent WEB device placement

Case No.ComplicationsComplication CategoryWEB DeviceAcute or Elective ProcedurePretreatment mRS ScoreDischarge mRS ScoremRS Score at >3-Mo FUAdjunct UsedDays From Procedure to EventEvent Related to WEB Device?
1Failed integrity test, other (transient neurological symptoms)DeviceDLElective000No0/233Yes/no
2NondetachmentDeviceDLAcute400No0Yes
3Delivery wire caughtADDLElective100Yes0No
4WEB wrong size, device protrusionDeviceDLElective000Yes0Yes
5WEB wrong size, TEDeviceSLElective000Yes0/0Yes
6WEB wrong sizeDeviceSLAcute100No183Yes
7TE, other (peripheral vascular event)Device, procedureDLAcute500No0/0Yes/no
8TEDeviceDLElective000No70/4Yes
9TEDeviceDLElective000No0Yes
10TEDeviceDLElective000No0Yes
11TEProcedureSLSAcute500No0No
12TEADSLSAcute322No0No
13TEProcedureSLElective221No0No
14TEDeviceDLElective000No72Yes
15TEDeviceSLElective000No24Yes
16Parent vessel occlusion, rupture, WEB twisted & compressedDevice, ADDLAcute120No0/0/0Yes/no
17Parent vessel occlusionDeviceDLElective000Yes0Yes
18RuptureADSLSElective000Yes0No
19Other (transient headache)DiseaseDLElective000No7No
20Other (aneurysm edema causing confusion-resolved)DeviceSLElective000No18Yes
21Other (wound infection)OtherSLAcute500No16No
22Procedural (alopecia), other (transient neurological symptoms)Disease, procedureSLElective000No87/87No/no
23Other (SAH on LP, delayed rupture)DeviceSLElective000No218Yes
24Access issue (abandoned)ProcedureDL/SL/SLSElective00NRYes0No
25Groin hematoma, access issue (abandoned)ProcedureNRElective00NRNo1No
26Access issue (abandoned)ProcedureDLElective000No0No
27Access issue (abandoned)ProcedureDLElective00NRYes0No
28Access issue (abandoned)ProcedureNRElective000No0No
29Access issue (abandoned)ProcedureDLElective00NRNo0No
LP = lumbar puncture; NR = not recorded.

Clinical Outcomes at Discharge and Follow-Up

All patients (109) had a discharge mRS score recorded. One hundred of the 109 patients had a > 3-month follow-up mRS score recorded; 9 patients had missing mRS scores at 3 or more months. Thus, long-term follow-up results are considered among 100 patients. The latest follow-up appointment and/or radiographic studies available were used for the assessment.

Preoperatively, 96 patients (88.1%, 95% CI 80.5, 93.5) had an mRS score < 3 (44.4% acute procedures, 96.7% elective) and 13 patients (11.9%, 95% CI 6.5, 19.5) had a score ≥ 3 (55.6% acute, 3.3% elective). Eighty patients (73.4%) had an mRS score of 0 (6.3% acute), 11 patients (10.1%) had an mRS score of 1 (9% acute), 5 patients (4.6%) had an mRS score of 2 (0% acute), 4 patients (3.7%) had an mRS score of 3 (50% acute), 4 patients (3.7%) had a score of 4 (75% acute), and 5 patients (4.6%) had a score of 5 (100% acute).

At discharge, 102 patients (93.6%, 95% CI 87.2, 97.4) had an mRS score < 3 (94.4% acute procedures, 93.4% elective) and 7 patients (6.4%, 95% CI 2.6, 12.8) had a score ≥ 3 (5.6% acute, 6.6% elective). Eighty-six patients (78.9%) had an mRS score of 0 (15.1% acute), 9 (8.2%) had a score of 1 (22.2% acute), 7 (6.4%) had a score of 2 (28.6% acute), 6 (5.5%) had a score of 3 (0% acute), 1 (0.9%) had a score of 4 (100% acute), and none had a score of 5 or 6.

At the > 3-month follow-up (100 patients), 91 patients (91%, 95% CI 83.6, 95.8) had an mRS score < 3 (100% acute procedures, 89.2% elective) and 9 patients (9%, 95% CI 4.2, 16.4) had an mRS score ≥ 3 (0% acute, 10.8% elective). Seventy-seven patients (77%) had an mRS score of 0 (19.5% acute), 8 (8%) had a score of 1 (1.3% acute), 6 (6%) had a score of 2 (16.7% acute), 4 (4%) had a score of 3 (0% acute), 0% had a score of 4 or 5, and 5 (5%) had a score of 6 (0% acute).

The evolution of the mRS score from before surgery to discharge showed that for 17.4% of patients (95% CI 10.8, 25.9) the mRS score improved (61.1% acute procedures, 8.8% elective), for 7.3% of patients (95% CI 3.2, 14.0) the mRS score deteriorated (5.6% acute, 7.7% elective), and for 75.2% of patients (95% CI 66.0, 83.0) the mRS score stayed the same (33.3% acute, 83.5% elective). At the follow-up (compared with preoperatively) the mRS score was better for 21.0% of patients (95% CI 13.5, 30.3; 76.5% acute, 9.6% elective), was worse for 12% (95% CI 6.4, 20.0; 0% acute, 14.5% elective), and stayed the same for 67.0% (95% CI 56.9, 76.1; 23.5% acute, 75.9% elective).

Overall morbidity at discharge was 1.8% (2 of 109 patients). One patient (Case 1; Table 2) had thromboembolism secondary to the procedure in addition to vasospasm from an acute SAH. A second patient (Case 4) developed right cerebellar infarcts and cerebellar ataxia 5 days after the procedure. Overall morbidity at the > 3-month followup was 6% (6 of 100). Morbidity was present if there was an increase in the mRS score to > 2. The patient in Case 4 did not improve at follow-up and thus was included in this later morbidity group. The other 5 patients were also included in the mortality group. The patient in Case 2 had a procedural thromboembolic event and developed hemianopia. The patient in Case 3, who underwent an elective procedure, had a procedural aneurysm rupture from a Synchro microwire. This patient also had a thromboembolic event, thought to be the result of a WEB device, causing right upper limb weakness and numbness. The patient in Case 8 had parent-vessel occlusion secondary to the inferior edge of the WEB device sitting across the proximal edge of A2. The clinician attempted to stent with the aim of preventing occlusion; however, it failed, and aggressive antiplatelet and hypertensive therapy were chosen. The patient in Case 11 had difficult intracranial access and had some mild left-hand weakness postprocedure (mRS Score 1). Other complications without clinical sequelae can be reviewed in Table 3.

Mortality and Other Complications

There were no in-hospital deaths. Five (5%) of 100 patients died after discharge and after the > 3-month follow-up. There were no device-related deaths as judged by 2 independent interventional neuroradiologists (A.M. and R.S.).

All later deaths occurred in patients with electively treated basilar aneurysms, constituting approximately 10% of the basilar aneurysms treated. All aneurysms in these cases were wide necked, but none were giant. One patient had a large, partially thrombosed aneurysm. The WEB device in all of these cases was the DL type, although 1 patient had retreatment with an SL device. One of the patients had a rebleed from a partially thrombosed basilar aneurysm (14 × 14 × 11 mm, 9-mm neck) previously treated with a WEB device. A second patient died of rupture of a second untreated, incidental small aneurysm 1 year after WEB treatment of the first aneurysm. Nine months after the first treatment of a basilar artery, a third patient represented with an aneurysm recurrence causing hydrocephalus. This patient was treated a second time with another WEB device and adjunctive coiling. This same patient then presented a third time with an SAH from the same aneurysm. Coiling was again performed, but the SAH was extensive, and there was pressure on the brainstem. A fourth patient died of brainstem ischemia from the basilar artery 10 days after retreatment with Y stenting and coiling for recurrence of a basilar tip aneurysm (previously treated electively with the WEB device). The fifth patient died of comorbidities (no association with the procedure or device).

When considering the overall complications, 14 were procedural, 17 were device related, 5 were related to the ancillary device, 6 were disease related, and 2 were categorized as “other.” Six patients had multiple categories. Within the symptomatic patient group, 4 complications were procedural, 3 were disease related, 2 were device related, 1 was related to the ancillary device, and 1 was classified as “other” (Tables 2 and 3).

The most common adverse event was thromboembolism, affecting 17 (15.6%) of 109 patients; 7 of these patients were symptomatic, and 10 had no clinical symptoms associated with the observed thromboembolic event. Seven cases were procedural, 9 were device related, 2 were ancillary device related, and none were disease related or “other” complications.

Anticoagulants were administered at the discretion of the clinician. As can be seen in Table 4, the anticoagulation regimen was variable throughout the population. Figure 3 shows that there is no obvious pattern between those who had clinical sequelae from the adverse event and those who did not. No centers employed pretreatment testing of antiplatelet therapy.

TABLE 4.

Anticoagulation for the thromboembolic events

Case No.Clinical SequelaeElective or Acute ProcedureAnticoagulation Regimen
PreproceduralIntraproceduralPostprocedural
1YesElectiveAspirin 200 mg 5 days, clopidogrel 75 mg 5 daysHeparin 5000 UAspirin 75 mg 3 mos, clopidogrel 75 mg 1 mo
2YesElectiveClopidogrel 75 mg (already on)Heparin 5000 U, aspirin 500 mgClopidogrel 75 mg indefinitely
3YesElectiveClopidogrel 600 mg 1 day, aspirin 300 mg 1 dayHeparin 5000 UNone (due to aneurysm rupture)
4YesElectiveAspirin 300 mg 1 dayHeparin 7000 UNone
5YesElectiveNoneHeparin 5000 U + 4800 UNone
6YesElectiveAspirin 75 mg (already taking)Heparin 9000 U, aspirin 500 mgAspirin 75 mg indefinitely
7YesElectiveAspirin 75 mg 5 days, clopidogrel 300 mg 1 dayHeparin 5000 UAspirin 75 mg 3 days
8NoElectiveAspirin 75 mg 7 days, clopidogrel 75 mg 7 daysHeparin 6000 UAspirin 75 mg 1 yr, clopidogrel 75 mg 5 mos
9NoElectiveNoneHeparin 5000 UAspirin 75 mg 6 wks
10NoElectiveNoneHeparin 5000 U, aspirin 500 mg, ReoPro 10 mgHeparin 20,000 U 1 day, aspirin 150 mg 12 mos, clopidogrel 75 mg 12 mos
11NoAcuteAspirin 300 mg 1 dayHeparin 7000 U, clopidogrel 600 mg, ReoPro 20 mgNone (acute)
12NoElectiveAspirin 300 mg, clopidogrel 600 mgHeparin 6500 UAspirin 75 mg 12 mos, clopidogrel 75 mg 3 mos
13NoElectiveNoneHeparin 5000 U, aspirin 1000 mgAspirin 75 mg 3 mos
14NoAcuteNoneAspirin 500 mg, heparin 5000 UNone (acute)
15NoAcuteNoneHeparin 5000 U, aspirin 500 mgNone (acute)
16No (delayed TE)ElectiveNoneHeparin 5000 U, aspirin 500 mgNone
17NoElectiveClopidogrel 600 mg for 1 day, aspirin 300 mg for 1 dayHeparin 1500 UAspirin 75 mg 4 mos
FIG. 3.
FIG. 3.

Bar graph showing the percentage of patients receiving anticoagulation preprocedurally, intraprocedurally, and postprocedurally and who suffered thromboembolic complications. Figure is available in color online only.

Complications specific to the WEB device numbered 17 (15.6%) among the 109 patients; 2 patients were symptomatic. Twelve patients (70.6%) had WEB DL devices, 5 had SL devices (29.4%), and none had SLS devices (11.8%). The percentage of WEB DL devices within the device complication group (70.6%) is higher than the overall percentage of successfully deployed DL devices (54.8%). This suggests that the DL device may be associated with more complications; however, the sample is not large enough to draw reliable conclusions. Among the 17 device-related complications, 12 (70.6%) were immediate (0–7days), 2 (11.8%) occurred more than 7 days but less than 1 month after the procedure, 2 (11.8%) occurred more than 1 month but less than 6 months after the procedure, and 1 (5.9%) occurred more than 6 months but less than 1 year after the procedure. No morbidity (an increase in the mRS score to > 2) or mortality was associated with complications specific to the WEB device.

Learning Curve

On performing statistical analysis, we found no correlation to suggest that there was a learning curve with the device, but the numbers are insufficient to establish this. The analysis was performed using a split after the fifth case at each center, a split after the first half of patients from the full population, and a split after the first half of cases at each center. However, 14 centers were included in the study, and many different factors were taken into account. Because we used a registry, we did not have data regarding which clinician performed the procedure, so the analysis was done for each center rather than for an individual clinician (and some centers had multiple clinicians). The WEB device evolved during the study; the DL device was used initially, and the SL and SLS devices were used more in the later cases.

Abandoned Procedures

In our patient cohort, 8 procedures had to be abandoned. Two of the patients went on to have successful insertion of a WEB device at a later date. All 8 of the abandoned procedures were elective, and all patients in these cases had access issues. One patient had a groin hematoma, 1 had a thromboembolism, and 1 died during the follow-up period due to comorbidities. Following the attempted procedure, 2 patients had clinical sequelae and 6 did not. All abandoned procedures were included in the data analysis.

Discussion

The prevalence of cerebral aneurysms is considered to be approximately 3% in the general population.25 Approximately 8 patients per 100,000 of the population will experience rupture of a brain aneurysm.27 Since the ISAT, most cerebral aneurysms in Western Europe have been treated using endovascular techniques. However, this procedure can be very technically challenging, particularly in wide-necked bifurcation aneurysms.

Current endovascular techniques involve balloon-assisted coiling, stent-assisted coiling, flow diverters, and in some cases Y or T stenting. These techniques are complex, need considerable experience, require dual antiplatelet therapy to prevent thromboembolic complications, and have a high rate of adverse events.5,7 The benefit of stenting is diminished by the use of long-term antiplatelet medications. Many of the aneurysms in the current study, particularly those arising at the MCA bifurcation, would be surgical candidates for the above reasons.

The WEB device has been designed to facilitate interventional treatment in wide-necked aneurysms. The procedure is simple and fast and avoids a long-term antiplatelet regimen. The device is a novel solution for the treatment of wide-necked, complex bifurcation aneurysms. As with any new device, discovering its safety profile is paramount to assessing its utility. This series has been published to provide real-world outcomes that include every consecutive UK patient who received a WEB implant during introduction of the device into clinical use. While Sequent Medical funded the database, data entry and analysis were conducted by clinicians and research nurses independent of the company and were externally adjudicated. The study provides an unbiased snapshot of current practice, outcomes, and initial experience with the WEB device in clinical practice. Adverse events entered into the database were independently adjudicated and categorized by 2 senior interventional neuroradiologists. Most patients selected were not eligible for standard coiling and would have required adjunct devices. The surgical option was considered in the selected patients, but they either could not or did not want to have their aneurysm clipped.

The first publication on the WEB device described an animal study by Ding et al. in 2011.6 The authors found that the WEB device performed in a fashion similar to the platinum coil in 24 rabbits over the time frame of 1 year, suggesting that the WEB device could compete as a primary treatment device. A second animal study showed that 4 of 5 aneurysms were completely occluded immediately after placement of the WEB device. This study was followed by a series of 3 clinical case reports between 2011 and 2013 with a total of 6 patients having no recorded complications.4,12,26 Later, a case series of 6 ruptured aneurysms showed a procedural thromboembolic rate of 33.3%.2 Another series of 7 elective anterior communicating artery aneurysms had a procedural thromboembolic event rate of 14.3%.9

Table 5 presents 9 larger case studies with between 20 and 109 patients,1,15,16,19,21–24 showing all events reported in the studies including those without clinical sequelae. Given the importance of data on the safety profile of the device, current observational studies are key to ensuring evidence-based practices. This study from the UK is a timely addition to the growing body of European data. Table 5 demonstrates that the safety profile is similar across the studies. Procedure-related thromboembolism is the most common complication, having an impact on all of these larger studies (7.8%–18.8%) and raising the question of whether a standard anticoagulation policy should be employed for a limited time in patients receiving a WEB device. In the acute situation, however, preprocedural and postprocedural anticoagulation may not be an option.

TABLE 5.

Larger case series assessing complications of WEB device placement*

ParameterPresent StudyLeeds DataPierot et al., 2016Papagiannaki et al., 2014Lubicz et al., 2014Lubicz et al., 2013Behme et al., 2015Pierot et al., 2015Pierot et al., 2013Pierot et al., 2012
No. of patients1092211377451851623220
Mortality5.0%0.0%0.0%0.0%2.2%0.0%0.0%0.0%0.0%0.0%
Morbidity (mRS score >2 + increase of 1 point on mRS from preop)6.0%4.5%2.7%0.0%6.7%5.6%0.0%3.2%3.1%0.0%
Procedural complication
  TE (clinical sequelae)15.6% (6.4%)13.6% (4.5%)15.0% (1.8%)11.7% (3.9%)11.1% ()11.1% (5.6%)7.8% (0%)16.1% (1.6%)18.8% (9.4%)10% (0%)
  Intraop rupture2.8%4.5%0.9%1.3%2.2%5.6%2.0%1.6%3.1%0%

Studies with >15 patients, excluding abandoned procedures.

Pending publication.

Percentage could not be determined based on information in the study.

There has been a question of whether the thromboembolic events are secondary to the small marker at the base of the WEB implant or related to the access devices. A similar incidence of thromboembolic problems has been seen in treatments with flow diverters.8,18 The present study includes the early experience of operators and a greater number of WEB DL devices, which need larger access devices. We believe that this complication is probably related to large access devices rather than the WEB marker. The more recent trend is toward the SL and SLS devices, which are used with better access devices and smaller catheters as well as greater experience with the devices, which may reduce the risk of thromboembolic events.

The frequency of adverse events in our paper does not appear to differ between the acute or elective cases. The 9 cases with a worsening postprocedural mRS score were all in the elective group in patients with complex and difficult to treat aneurysms.

Ten percent of the basilar aneurysms treated in our series occurred in patients who subsequently died. None of these late deaths were attributed to the WEB device, and all happened more than 250 days from the date of the WEB procedure. One case was a delayed rupture at 300 days after the procedure. There was 1 delayed rupture of a different aneurysm 336 days after the procedure, and there was a death from the rupture of a partially thrombosed complex aneurysm after 259 days. A thromboembolic event occurred after a second procedure with a Y stent 279 days after the WEB procedure. A fifth patient died of comorbidities after 306 days.

Study Limitations and Strengths

A limitation of this study is that it is based on a registry. The WEB DL device was used in the early part of the study and is no longer routinely used in our clinical practice. Nine patients were lost to follow-up. There was also no consistent antiplatelet regimen used across the centers in the UK. The strength of the study is its consecutive series of patients from multiple centers, so it is probably representative of the introduction of the device into clinical practice. Moreover, the results have been reviewed and adjudicated by senior consultant interventional neuroradiologists.

The Raymond occlusion scale was used to record aneurysm occlusion success in this database (assessed within a subgroup of patients). This scale was developed to assess coiling and does not take into account the morphology of the WEB device. Thus, aneurysms with a proximal recess, proximal basket opacification, or slow flow within the WEB will not be correctly categorized. The recently developed Leeds WEB aneurysm occlusion scale has been carefully developed to include the nuances of the WEB device and will be invaluable for future monitoring of the device.13

This series has a wide selection of predominantly wide-necked aneurysms, a range of aneurysm locations, and a significant proportion of acute cases. The data suggest that the WEB device is a useful treatment option that makes more complex, wide-necked bifurcation aneurysms good candidates for endovascular treatment. The selection of predominantly basilar and MCA aneurysms in this UK series is different from that in other previous WEB publications. This is because most aneurysms included in this series were unsuitable for standard coiling and for surgery, which was judged to present a higher risk.

Incorrect sizing was recorded as an adverse event 4 times. We suggest using precise anteroposterior and lateral 3D measurements of the aneurysm to identify the appropriate implant size. Experience in simulation training is recommended before WEB implantation.

Conclusions

The UK results show that the WEB device has an acceptable safety profile for clinical use in selected aneurysms. A small risk of thromboembolic events should be minimized with appropriate anticoagulation in the perioperative period and correct sizing of the device. There is scope for further evaluation and optimization of an anticoagulation regimen for the WEB device.

Acknowledgments

We acknowledge support from Sequent Medical via Patricia Boyer and Phillippa Braidley.

Appendix

Participating Centers

1) Dr. Bhattacharya, Dr. Dervin, Irene Scott, Glasgow; 2) Dr. Patankar, Dr. Goddard, Miss Lawson, Jon Pearce, Leeds General Infirmary (lead center); 3) Dr. Lamin, Dr. Thomas, Joe Leyon, Birmingham; 4) Dr. Gholkar, Dr. White, Dr. Mitra, Dr. Krishnan, Nicola Hind, Newcastle; 5) Dr. Maliakal, Dr. Harrison, Hull Royal Infirmary; 6) Dr. Joshi, Cardiff; 7) Dr. Nair, Dr. Nagaraja, Coventry; 8) Dr. Adam Rennie, London; 9) Dr. Hewadkar, Dr. Williams, Dr. Stockley, Manchester; 10) Dr. Sonwalkar, Siddharta Wuppalapati, Steven Brown, Preston; 11) Dr. Alkilani, Romford; 12) Dr. Nahser, Dr. Putheran, Dr. Chandran, Liverpool; 13) Dr. Rennie, Belfast; and 14) Dr. Keston, Dr. Downer, Brian Innes, Edinburgh.

Disclosures

Dr. Gholkar is a consultant for Sequent Medical. Dr. Lamin has a consulting and training contract with Covidien, Sequent Medical, and Medtronic. Dr. Molyneux is a consultant for Sequent Medical. Dr. Patankar is a consultant for Sequent Medical, Stryker, and Pulsar Vascular and has received funding from Sequent Medical for statistical analysis in this study. Dr. Sellar is a consultant for Sequent Medical. Sequent Medical funded Axiom Fusion eClinical Suite to build the WEB UK study database and provided funding for the statistical analysis.

Author Contributions

Conception and design: Patankar. Acquisition of data: all authors. Analysis and interpretation of data: Patankar, Lawson. Drafting the article: Patankar, Lawson. Critically revising the article: all authors. Reviewed submitted version of manuscript: all authors. Approved the final version of the manuscript on behalf of all authors: Patankar. Statistical analysis: Lawson. Administrative/technical/material support: Lawson. Study supervision: Patankar.

References

  • 1

    Behme DBerlis AWeber W: Woven EndoBridge intrasaccular flow disrupter for the treatment of ruptured and unruptured wide-neck cerebral aneurysms: report of 55 cases. AJNR Am J Neuroradiol 36:150115062015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 2

    Caroff JMihalea CDargento FNeki HIkka LBenachour N: Woven Endobridge (WEB) Device for endovascular treatment of ruptured intracranial wide-neck aneurysms: a single-center experience. Neuroradiology 56:7557612014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3

    Chiu AHCheung AKWenderoth JDDe Villiers LRice HPhatouros CC: Long-term follow-up results following elective treatment of unruptured intracranial aneurysms with the Pipeline embolization device. AJNR Am J Neuroradiol 36:172817342015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4

    Colla RCirillo LPrinciotta CDall'olio MMenetti FVallone S: Treatment of wide-neck basilar tip aneurysms using the WEB II device. Neuroradiol J 26:6696772013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5

    D'Urso PILanzino GCloft HJKallmes DF: Flow diversion for intracranial aneurysms: a review. Stroke 42:236323682011

  • 6

    Ding YHLewis DAKadirvel RDai DKallmes DF: The Woven EndoBridge: a new aneurysm occlusion device. AJNR Am J Neuroradiol 32:6076112011

  • 7

    Fargen KMMocco JNeal DDewan MCReavey-Cantwell JWoo HH: A multicenter study of stent-assisted coiling of cerebral aneurysms with a Y configuration. Neurosurgery 73:4664722013

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8

    Fargen KMVelat GJLawson MFMocco JHoh BL: Review of reported complications associated with the Pipeline embolization device. World Neurosurg 77:4034042012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9

    Gherasim DNGory BSivan-Hoffmann RPierot LRaoult HGauvrit JY: Endovascular treatment of wide-neck an terior communicating artery aneurysms using WEB-DL and WEB-SL: short-term results in a multicenter study. AJNR Am J Neuroradiol 36:115011542015

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10

    Guglielmi GViñuela FDion JDuckwiler G: Electrothrombosis of saccular aneurysms via endovascular approach. Part 2: Preliminary clinical experience. J Neurosurg 75:8141991

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11

    Guglielmi GViñuela FSepetka IMacellari V: Electrothrombosis of saccular aneurysms via endovascular approach. Part 1: Electrochemical basis, technique, and experimental results. J Neurosurg 75:171991

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12

    Klisch JSychra VStrasilla CLiebig TFiorella D: The Woven EndoBridge cerebral aneurysm embolization device (WEB II): initial clinical experience. Neuroradiology 53:5996072011

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 13

    Lawson AGoddard TRoss STyagi ADeniz KPatankar T: Endovascular treatment of cerebral aneurysms using the Woven EndoBridge technique in a single center: preliminary results.. J Neurosurg [epub ahead of print April 15 2016. DOI: 10.3171/20154.JNS142456]

    • Search Google Scholar
    • Export Citation
  • 14

    Lawson ALChandran APuthuran MGoddard TNahser HPatankar T: Initial experience of coiling cerebral aneurysms using the new Comaneci device. J Neurointerv Surg 8:e322016

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15

    Lubicz BKlisch JGauvrit JYSzikora ILeonardi MLiebig T: WEB-DL endovascular treatment of wide-neck bifurcation aneurysms: short- and midterm results in a European study. AJNR Am J Neuroradiol 35:4324382014

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 16

    Lubicz BMine BCollignon LBrisbois DDuckwiler GStrother C: WEB device for endovascular treatment of wide-neck bifurcation aneurysms. AJNR Am J Neuroradiol 34:120912142013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17

    Molyneux AKerr RStratton ISandercock PClarke MShrimpton J: International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial. Lancet 360:126712742002

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 18

    Murthy SBShah SShastri AVenkatasubba Rao CPBershad EMSuarez JI: The SILK flow diverter in the treatment of intracranial aneurysms. J Clin Neurosci 21:2032062014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 19

    Papagiannaki CSpelle LJanuel ACBenaissa AGauvrit JYCostalat V: WEB intrasaccular flow disruptor-prospective, multicenter experience in 83 patients with 85 aneurysms. AJNR Am J Neuroradiol 35:210621112014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20

    Pierot LCognard CSpelle LMoret J: Safety and efficacy of balloon remodeling technique during endovascular treatment of intracranial aneurysms: critical review of the literature. AJNR Am J Neuroradiol 33:12152012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 21

    Pierot LKlisch JCognard CSzikora IMine BKadziolka K: Endovascular WEB flow disruption in middle cerebral artery aneurysms: preliminary feasibility, clinical, and anatomical results in a multicenter study. Neurosurgery 73:27352013

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22

    Pierot LLiebig TSychra VKadziolka KDorn FStrasilla C: Intrasaccular flow-disruption treatment of intracranial aneurysms: preliminary results of a multicenter clinical study. AJNR Am J Neuroradiol 33:123212382012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 23

    Pierot LMoret JTurjman FHerbreteau DRaoult HBarreau X: WEB treatment of intracranial aneurysms: feasibility, complications, and 1-month safety results with the WEB DL and WEB SL/SLS in the French Observatory. AJNR Am J Neuroradiol 36:9229272015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 24

    Pierot LSpelle LMolyneux AByrne J: Clinical and anatomical follow-up in patients with aneurysms treated with the WEB device: 1-year follow-up report in the cumulated population of 2 prospective, multicenter series (WEBCAST and French Observatory). Neurosurgery 78:1331412016

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 25

    Vlak MHAlgra ABrandenburg RRinkel GJ: Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol 10:6266362011

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 26

    Wallner AKBroussalis EHauser TTrinka EKiller-Oberpfalzer M: Coiling after treatment with the woven EndoBridge cerebral aneurysm embolization device. A case report. Interv Neuroradiol 18:2082122012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 27

    Wardlaw JMWhite PM: The detection and management of unruptured intracranial aneurysms. Brain 123:2052212000

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Article Information

Contributor Notes

Correspondence Tufail Patankar, Department of Neurosurgery, Leeds Teaching Hospitals NHS Trust, Great George St., Leeds LS1 3EX, United Kingdom. email: tufail.patankar@nhs.net.INCLUDE WHEN CITING Published online February 3, 2017; DOI: 10.3171/2016.9.JNS152849.Disclosures Dr. Gholkar is a consultant for Sequent Medical. Dr. Lamin has a consulting and training contract with Covidien, Sequent Medical, and Medtronic. Dr. Molyneux is a consultant for Sequent Medical. Dr. Patankar is a consultant for Sequent Medical, Stryker, and Pulsar Vascular and has received funding from Sequent Medical for statistical analysis in this study. Dr. Sellar is a consultant for Sequent Medical. Sequent Medical funded Axiom Fusion eClinical Suite to build the WEB UK study database and provided funding for the statistical analysis.

© AANS, except where prohibited by US copyright law.

Headings
Figures
  • View in gallery

    A: A WEB DL device deployed from a catheter into a bifurcation aneurysm. B: A WEB SL device. C: A WEB SLS device. Copyright Sequent Medical. Published with permission. Figure is available in color online only.

  • View in gallery

    Pie chart demonstrating the distribution of aneurysm locations. ACA = anterior cerebral artery; ACOM = anterior communicating artery; ICA = internal carotid artery; PCA = posterior cerebral artery; PCOM = posterior communicating artery. Figure is available in color online only.

  • View in gallery

    Bar graph showing the percentage of patients receiving anticoagulation preprocedurally, intraprocedurally, and postprocedurally and who suffered thromboembolic complications. Figure is available in color online only.

References
  • 1

    Behme DBerlis AWeber W: Woven EndoBridge intrasaccular flow disrupter for the treatment of ruptured and unruptured wide-neck cerebral aneurysms: report of 55 cases. AJNR Am J Neuroradiol 36:150115062015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 2

    Caroff JMihalea CDargento FNeki HIkka LBenachour N: Woven Endobridge (WEB) Device for endovascular treatment of ruptured intracranial wide-neck aneurysms: a single-center experience. Neuroradiology 56:7557612014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 3

    Chiu AHCheung AKWenderoth JDDe Villiers LRice HPhatouros CC: Long-term follow-up results following elective treatment of unruptured intracranial aneurysms with the Pipeline embolization device. AJNR Am J Neuroradiol 36:172817342015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 4

    Colla RCirillo LPrinciotta CDall'olio MMenetti FVallone S: Treatment of wide-neck basilar tip aneurysms using the WEB II device. Neuroradiol J 26:6696772013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 5

    D'Urso PILanzino GCloft HJKallmes DF: Flow diversion for intracranial aneurysms: a review. Stroke 42:236323682011

  • 6

    Ding YHLewis DAKadirvel RDai DKallmes DF: The Woven EndoBridge: a new aneurysm occlusion device. AJNR Am J Neuroradiol 32:6076112011

  • 7

    Fargen KMMocco JNeal DDewan MCReavey-Cantwell JWoo HH: A multicenter study of stent-assisted coiling of cerebral aneurysms with a Y configuration. Neurosurgery 73:4664722013

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 8

    Fargen KMVelat GJLawson MFMocco JHoh BL: Review of reported complications associated with the Pipeline embolization device. World Neurosurg 77:4034042012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 9

    Gherasim DNGory BSivan-Hoffmann RPierot LRaoult HGauvrit JY: Endovascular treatment of wide-neck an terior communicating artery aneurysms using WEB-DL and WEB-SL: short-term results in a multicenter study. AJNR Am J Neuroradiol 36:115011542015

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 10

    Guglielmi GViñuela FDion JDuckwiler G: Electrothrombosis of saccular aneurysms via endovascular approach. Part 2: Preliminary clinical experience. J Neurosurg 75:8141991

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 11

    Guglielmi GViñuela FSepetka IMacellari V: Electrothrombosis of saccular aneurysms via endovascular approach. Part 1: Electrochemical basis, technique, and experimental results. J Neurosurg 75:171991

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 12

    Klisch JSychra VStrasilla CLiebig TFiorella D: The Woven EndoBridge cerebral aneurysm embolization device (WEB II): initial clinical experience. Neuroradiology 53:5996072011

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 13

    Lawson AGoddard TRoss STyagi ADeniz KPatankar T: Endovascular treatment of cerebral aneurysms using the Woven EndoBridge technique in a single center: preliminary results.. J Neurosurg [epub ahead of print April 15 2016. DOI: 10.3171/20154.JNS142456]

    • Search Google Scholar
    • Export Citation
  • 14

    Lawson ALChandran APuthuran MGoddard TNahser HPatankar T: Initial experience of coiling cerebral aneurysms using the new Comaneci device. J Neurointerv Surg 8:e322016

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 15

    Lubicz BKlisch JGauvrit JYSzikora ILeonardi MLiebig T: WEB-DL endovascular treatment of wide-neck bifurcation aneurysms: short- and midterm results in a European study. AJNR Am J Neuroradiol 35:4324382014

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 16

    Lubicz BMine BCollignon LBrisbois DDuckwiler GStrother C: WEB device for endovascular treatment of wide-neck bifurcation aneurysms. AJNR Am J Neuroradiol 34:120912142013

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 17

    Molyneux AKerr RStratton ISandercock PClarke MShrimpton J: International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial. Lancet 360:126712742002

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 18

    Murthy SBShah SShastri AVenkatasubba Rao CPBershad EMSuarez JI: The SILK flow diverter in the treatment of intracranial aneurysms. J Clin Neurosci 21:2032062014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 19

    Papagiannaki CSpelle LJanuel ACBenaissa AGauvrit JYCostalat V: WEB intrasaccular flow disruptor-prospective, multicenter experience in 83 patients with 85 aneurysms. AJNR Am J Neuroradiol 35:210621112014

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 20

    Pierot LCognard CSpelle LMoret J: Safety and efficacy of balloon remodeling technique during endovascular treatment of intracranial aneurysms: critical review of the literature. AJNR Am J Neuroradiol 33:12152012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 21

    Pierot LKlisch JCognard CSzikora IMine BKadziolka K: Endovascular WEB flow disruption in middle cerebral artery aneurysms: preliminary feasibility, clinical, and anatomical results in a multicenter study. Neurosurgery 73:27352013

    • Crossref
    • Search Google Scholar
    • Export Citation
  • 22

    Pierot LLiebig TSychra VKadziolka KDorn FStrasilla C: Intrasaccular flow-disruption treatment of intracranial aneurysms: preliminary results of a multicenter clinical study. AJNR Am J Neuroradiol 33:123212382012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 23

    Pierot LMoret JTurjman FHerbreteau DRaoult HBarreau X: WEB treatment of intracranial aneurysms: feasibility, complications, and 1-month safety results with the WEB DL and WEB SL/SLS in the French Observatory. AJNR Am J Neuroradiol 36:9229272015

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 24

    Pierot LSpelle LMolyneux AByrne J: Clinical and anatomical follow-up in patients with aneurysms treated with the WEB device: 1-year follow-up report in the cumulated population of 2 prospective, multicenter series (WEBCAST and French Observatory). Neurosurgery 78:1331412016

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 25

    Vlak MHAlgra ABrandenburg RRinkel GJ: Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol 10:6266362011

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 26

    Wallner AKBroussalis EHauser TTrinka EKiller-Oberpfalzer M: Coiling after treatment with the woven EndoBridge cerebral aneurysm embolization device. A case report. Interv Neuroradiol 18:2082122012

    • Crossref
    • PubMed
    • Search Google Scholar
    • Export Citation
  • 27

    Wardlaw JMWhite PM: The detection and management of unruptured intracranial aneurysms. Brain 123:2052212000

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