Learning from failure: persistence of aneurysms following pipeline embolization

OBJECTIVE A detailed analysis was performed of anterior circulation aneurysms treated with a Pipeline Embolization Device (PED) that did not progress to complete occlusion by 1-year follow-up. Angiography was performed with the purpose of identifying specific factors potentially responsible for these failed outcomes. METHODS From among the first 100 patients with anterior circulation aneurysms, 92 underwent 1-year follow-up angiography and were individually studied through review of their pre- and postembolization studies. RESULTS Nineteen aneurysms (21%) remained unoccluded at 12 months. Independent predictors of treatment failure, identified by logistic regression analysis, were found to be fusiform aneurysm morphology, decreasing dome-to-neck ratio, and the presence of a preexisting laser-cut stent. Further examination of individual cases identified several common mechanisms—device malapposition, inadequate coverage of the aneurysm neck with persistent exchange across the device, and the incorporation of a branch vessel into the aneurysm fundus—potentially contributing to failed treatment in these settings. CONCLUSIONS Attention to specific features of the aneurysm and device construct can frequently identify cases predisposed to treatment failure and suggest strategies to maximize favorable outcomes.

Download Full-text

Predictors of cerebral aneurysm persistence and occlusion after flow diversion: a single-institution series of 445 cases with angiographic follow-up

Journal of Neurosurgery ◽

10.3171/2017.11.jns171738 ◽

2018 ◽

Vol 130 (1) ◽

pp. 259-267 ◽

Cited By ~ 16

Author(s):

Matthew T. Bender ◽

Geoffrey P. Colby ◽

Li-Mei Lin ◽

Bowen Jiang ◽

Erick M. Westbroek ◽

...

Keyword(s):

Cerebral Artery ◽

Flow Diversion ◽

Single Institution ◽

Anterior Circulation ◽

Complete Occlusion ◽

Aneurysm Size ◽

Branch Vessel ◽

Aneurysm Occlusion ◽

Anterior Circulation Aneurysms

OBJECTIVEFlow diversion requires neointimal stent overgrowth to deliver aneurysm occlusion. The existing literature on aneurysm occlusion is limited by heterogeneous follow-up, variable antiplatelet regimens, noninvasive imaging modalities, and nonstandard occlusion assessment. Using a large, single-center cohort with low attrition and standardized antiplatelet tapering, the authors evaluated outcomes after flow diversion of anterior circulation aneurysms to identify predictors of occlusion and aneurysm persistence.METHODSData from a prospective, IRB-approved database was analyzed for all patients with anterior circulation aneurysms treated by flow diversion with the Pipeline embolization device (PED) at the authors’ institution. Follow-up consisted of catheter cerebral angiography at 6 and 12 months postembolization. Clopidogrel was discontinued at 6 months and aspirin was reduced to 81 mg daily at 12 months. Occlusion was graded as complete, trace filling, entry remnant, or aneurysm filling. Multivariate logistic regression was performed to identify predictors of aneurysm persistence.RESULTSFollow-up catheter angiography studies were available for 445 (91%) of 491 PED procedures performed for anterior circulation aneurysms between August 2011 and August 2016. Three hundred eighty-seven patients accounted for these 445 lesions with follow-up angiography. The population was 84% female; mean age was 56 years and mean aneurysm size was 6.6 mm. Aneurysms arose from the internal carotid artery (83%), anterior cerebral artery (13%), and middle cerebral artery (4%). Morphology was saccular in 90% of the lesions, and 18% of the aneurysms has been previously treated. Overall, complete occlusion was achieved in 82% of cases at a mean follow-up of 14 months. Complete occlusion was achieved in 72%, 78%, and 87% at 6, 12, and 24 months, respectively. At 12 months, adjunctive coiling predicted occlusion (OR 0.260, p = 0.036), while male sex (OR 2.923, p = 0.032), aneurysm size (OR 3.584, p = 0.011), and incorporation of a branch vessel (OR 2.206, p = 0.035) predicted persistence. Notable variables that did not predict aneurysm occlusion were prior treatments, vessel of origin, fusiform morphology, and number of devices used.CONCLUSIONSThis is the largest single-institution study showing high rates of anterior circulation aneurysm occlusion after Pipeline embolization. Predictors of persistence after flow diversion included increasing aneurysm size and incorporated branch vessel, whereas adjunctive coiling predicted occlusion.

Download Full-text

Embolization of Non-Ruptured Aneurysms

Interventional Neuroradiology ◽

10.1177/15910199990050s117 ◽

1999 ◽

Vol 5 (1_suppl) ◽

pp. 93-96 ◽

Cited By ~ 1

Author(s):

C.F. Dowd ◽

C.C. Phatouros ◽

A.M. Malek ◽

T.E. Lempert ◽

P.M. Meyers ◽

...

Keyword(s):

Intracranial Aneurysms ◽

Three Dimensional ◽

Giant Aneurysm ◽

Epidemiological Data ◽

Anterior Circulation ◽

Unruptured Aneurysms ◽

Aneurysm Neck ◽

Technical Developments ◽

History Of ◽

Anterior Circulation Aneurysms

Options for treatment of intracranial aneurysms have expanded with the advent of the Guglielmi Detachable Cod (GDC) eight years ago. We have reviewed 435 cases of intracranial aneurysms treated at UCSF by endovascular means using the GDC system. Of these, 55% represent anterior circulation aneurysms, and 45% are located in the posterior circulation. Additionally, 55% of the aneurysms presented with subarachnoid hemorrhage (SAH) and 45% were unruptured. Factors which hindered optimal coiling include the following: wide aneurysm neck in relation to the overall aneurysm size, mural thrombus, giant aneurysm, arteries originating from the aneurysm sac, and middle cerebral location. After initial experience was gained, we tended to avoid these aneurysms especially in the non-ruptured group. This may be especially important in light of new epidemiological data suggesting that the natural history of unruptured aneurysms is significantly lower than previously thought. New technical developments which may reduce the risk of treating unruptured aneurysms include the two-dimensional coil, the three-dimensional coil, the balloon-assist technique for wide-necked aneurysms, and combined stent-coil procedures.

Download Full-text

Transient Adenosine-Induced Asystole During the Surgical Treatment of Anterior Circulation Cerebral Aneurysms: Technical Note

Operative Neurosurgery ◽

10.1227/neu.0b013e3181f7ef46 ◽

2010 ◽

Vol 67 (suppl_2) ◽

pp. ons461-ons470 ◽

Cited By ~ 13

Author(s):

Ciaran J. Powers ◽

David R. Wright ◽

David L. McDonagh ◽

Cecil O. Borel ◽

Ali R. Zomorodi ◽

...

Keyword(s):

Cardiac Arrest ◽

Cerebral Aneurysms ◽

Technical Note ◽

Aortic Aneurysms ◽

Anterior Circulation ◽

Aneurysm Neck ◽

Short Period ◽

Delayed Complication ◽

Patient Responses ◽

Anterior Circulation Aneurysms

Abstract BACKGROUND: Transient adenosine-induced asystole is a reliable method for producing a short period of relative hypotension during surgical and endovascular procedures. Although the technique has been described in the endovascular treatment of brain arteriovenous malformations, aortic aneurysms, and posterior circulation cerebral aneurysms, little description of its use in anterior circulation aneurysms is available. OBJECTIVE: To assess the benefits of adenosine-induced transient asystole in complex anterior circulation aneurysms, to describe our experience in selected cases, and to provide the first experience of the use of adenosine in anterior circulation aneurysms. METHODS: The adenosine-induced cardiac arrest protocol allows us to titrate the duration of cardiac arrest on the basis of individual patient responses. The operative setup is the same as with all aneurysm clippings, with the addition of the placement of transcutaneous pacemakers as a precaution for prolonged bradycardia or asystole. Escalating doses of adenosine are given to determine the approximate dose that results in 30 seconds of asystole. When requested by the surgeon, the dose of adenosine is administered for definitive dissection and clipping. We present 6 cases in which this technique was used. RESULTS: The use of transient adenosine-induced asystole provided excellent circumferential visualization of the aneurysm neck and safe clip application. All patients did well neurologically and suffered no evidence of perioperative cerebral ischemia or delayed complication from the use of adenosine itself. CONCLUSION: Transient adenosine-induced asystole is a safe and effective technique in select circumstances that may aid in safe and effective aneurysm clipping. Along with the traditional techniques of brain relaxation, skull base approaches, and temporary clipping, adenosine-induced asystole facilitates circumferential visualization of the aneurysm neck and is another technique available to cerebrovascular surgeons.

Download Full-text

Transpalpebral Approach “Eyelid Incision” for Surgical Treatment of Intracerebral Aneurysms: Lessons Learned During a 10-Year Experience

Operative Neurosurgery ◽

10.1093/ons/opz217 ◽

2019 ◽

Cited By ~ 1

Author(s):

Gordon Mao ◽

Michael Gigliotti ◽

Khaled Aziz ◽

Khaled Aziz

Keyword(s):

Wound Healing ◽

Artery Aneurysm ◽

Postoperative Hemorrhage ◽

Lessons Learned ◽

Anterior Circulation ◽

Upper Eyelid ◽

Complete Obliteration ◽

Cosmetic Outcomes ◽

Anterior Circulation Aneurysms

Abstract BACKGROUND The classic pterional, pretemporal, and orbitozygomatic approaches achieve large areas of exposure with easy maneuverability. In select cases (eg, some anterior circulation aneurysms), the minimally invasive fronto-orbital craniotomy can yield adequate exposure that must be balanced with its risk of frontalis injury. OBJECTIVE To detail a 10-yr experience using the transpalpebral approach, characterized by an incision whose camouflage is the natural eyelid crease, notably the effectiveness and outcomes of this exposure for anterior circulation aneurysms. METHODS In this retrospective review, 82 patients with 88 aneurysms underwent a supraorbital frontal minicraniotomy via the eyelid incision performed by a single neurosurgeon and closure by an oculoplastic surgeon (2007-2016). Incision of the orbiculi oculi developed a plane between the muscle and orbital septum superiorly. Outcomes recorded included aneurysm occlusion or residual, treatment modality (clipping/wrapping), postoperative hemorrhage or stroke, postoperative wound healing, and overall cosmesis. RESULTS Of 85 (97%) aneurysms treated by clipping, postoperative and follow-up imaging showed complete obliteration in 81 (95%) aneurysms and residuals in 4 (5%). Cosmetic outcomes for the eyelid incision were excellent: 81 (99%) patients noted excellent wound healing at follow-up and no scarring; 1 patient developed significant temporalis wasting and upper eyelid scarring after posterior communicating artery aneurysm clipping. Overall, 13 minor and 8 major complications affected 19 patients. CONCLUSION Our findings confirm the versatility of the eyelid supraorbital frontal minicraniotomy for common anterior circulation aneurysms. This large series found that postoperative complication risks were similar to traditional techniques and cosmetic results were excellent.

Download Full-text

Parent vessel occlusion after Pipeline embolization of cerebral aneurysms of the anterior circulation

Journal of Neurosurgery ◽

10.3171/2016.9.jns152638 ◽

2017 ◽

Vol 127 (6) ◽

pp. 1333-1341 ◽

Cited By ~ 4

Author(s):

Matthew B. Potts ◽

Maksim Shapiro ◽

Daniel W. Zumofen ◽

Eytan Raz ◽

Erez Nossek ◽

...

Keyword(s):

Antiplatelet Therapy ◽

Parent Artery ◽

Parent Vessel ◽

Anterior Circulation ◽

Vessel Occlusion ◽

Complex Aneurysms ◽

Aneurysm Size ◽

Parent Vessel Occlusion ◽

Anterior Circulation Aneurysms

OBJECTIVEThe Pipeline Embolization Device (PED) is now a well-established option for the treatment of giant or complex aneurysms, especially those arising from the anterior circulation. Considering the purpose of such treatment is to maintain patency of the parent vessel, postembolization occlusion of the parent artery can be regarded as an untoward outcome. Antiplatelet therapy in the posttreatment period is therefore required to minimize such events. Here, the authors present a series of patients with anterior circulation aneurysms treated with the PED who subsequently experienced parent vessel occlusion (PVO).METHODSThe authors performed a retrospective review of all anterior circulation aneurysms consecutively treated at a single institution with the PED through 2014, identifying those with PVO on follow-up imaging. Aneurysm size and location, number of PEDs used, and follow-up digital subtraction angiography results were recorded. When available, pre- and postembolization platelet function testing results were also recorded.RESULTSAmong 256 patients with anterior circulation aneurysms treated with the PED, the authors identified 8 who developed PVO after embolization. The mean aneurysm size in this cohort was 22.3 mm, and the number of PEDs used per case ranged from 2 to 10. Six patients were found to have asymptomatic PVO discovered incidentally on routine follow-up imaging between 6 months and 3 years postembolization, 3 of whom had documented “delayed” PVO with prior postembolization angiograms confirming aneurysm occlusion and a patent parent vessel at an earlier time. Two additional patients experienced symptomatic PVO, one of which was associated with early discontinuation of antiplatelet therapy.CONCLUSIONSIn this large series of anterior circulation aneurysms, the authors report a low incidence of symptomatic PVO, complicating premature discontinuation of postembolization antiplatelet or anticoagulation therapy. Beyond the subacute period, asymptomatic PVO was more common, particularly among complex fusiform or very large–necked aneurysms, highlighting an important phenomenon with the use of PED for the treatment of anterior circulation aneurysms, and suggesting that extended periods of antiplatelet coverage may be required in select complex aneurysms.

Download Full-text

Microsurgical clipping of the anterior circulation aneurysms

JBNC - JORNAL BRASILEIRO DE NEUROCIRURGIA ◽

10.22290/jbnc.v20i4.1001 ◽

2018 ◽

Vol 20 (4) ◽

pp. 409-414

Author(s):

Carlos Eduardo Da Silva ◽

Paulo Eduardo Peixoto De Freitas ◽

Alicia Del Carmen Becerra Romero ◽

Fáberson João Mocelin Oliveira ◽

Márcio Aloisio Bezerra Cavalcanti Rockenbach ◽

...

Keyword(s):

Relevant Literature ◽

Cerebral Aneurysms ◽

Series Data ◽

Anterior Communicating Artery ◽

Anterior Circulation ◽

Ruptured Aneurysms ◽

Microsurgical Clipping ◽

The Mean ◽

Anterior Circulation Aneurysms

Introduction: The authors present the analysis of the microsurgical clipping of 100 cerebral aneurysms of the anterior circulation and compare the series data with the literature. Methods: Eighty-eight patients presenting with 100 anterior circulation aneurysms operated on microsurgical techniques between 2002 and 2008 by the first author (CES) were retrospectively reviewed. Results: A total of 88 patients with 100 aneurysms of the anterior circulation were treated in a six years period. Fifty eight female (66%) and thirty male (34%) with nine patients (10.2%) presenting with multiple aneurysms. The mean age was 52 years (range from 26 to 76 years). Eighty five percent of the cases were ruptured aneurysms. The mean follow-up was 52.4 months (range from 5 to 76 months). The topography of the aneurysms was distributed as it follows: Anterior communicating artery (ACoA) 25%; posterior communicating artery (p-comm) 29%; middle cerebral artery (MCA) 27%; paraclinoidal aneurysms 8%; pericallosal artery 6% and internal carotid artery (ICA) tip 5%. The mortality was 7.9%, and such cases presenting with Hunt Hess graduation 3 and 4. The permanent morbidity was 4.5%, cases with Hunt Hess graduation 3 and 4. Perioperative rupture occurred in 17% of the cases, only in previous ruptured aneurysms. There was no clinical evidence of rebleeding during the follow-up period of the series. Conclusions: The microsurgical clipping of cerebral aneurysms of the anterior circulation is a safe and curative treatment for most of such lesions. At present, studies suggest evidences of superior results of surgery compared to the endovascular techniques in the rates of total occlusion of the aneurysms, lesser rates of rebleeding of the treated cases. The results of the present series are similar to the rates of the most relevant literature.

Download Full-text

Patency of anterior circulation branch vessels after Pipeline embolization: longer-term results from 82 aneurysm cases

Journal of Neurosurgery ◽

10.3171/2016.4.jns16147 ◽

2017 ◽

Vol 126 (4) ◽

pp. 1064-1069 ◽

Cited By ~ 50

Author(s):

Leonardo Rangel-Castilla ◽

Stephan A. Munich ◽

Naser Jaleel ◽

Marshall C. Cress ◽

Chandan Krishna ◽

...

Keyword(s):

Arterial Occlusion ◽

Side Branch ◽

Terminal Branch ◽

Anterior Choroidal Artery ◽

Anterior Circulation ◽

Branch Vessel ◽

Anterior Choroidal ◽

Choroidal Artery ◽

Ophthalmic Arteries

OBJECTIVE The Pipeline Embolization Device (PED) has become increasingly used for the treatment of intracranial aneurysms. Given its high metal surface area coverage, there is concern for the patency of branch vessels that become covered by the device. Limited data exist regarding the patency of branch vessels adjacent to aneurysms that are covered by PEDs. The authors assessed the rate of intracranial internal carotid artery, anterior circulation branch vessel patency following PED placement at their institution. METHODS The authors retrospectively reviewed the records of 82 patients who underwent PED treatment between 2009 and 2014 and in whom the PED was identified to cover branch vessels. Patency of the anterior cerebral, posterior communicating, anterior choroidal, and ophthalmic arteries was evaluated using digital subtraction angiography preoperatively and postoperatively after PED deployment and at longer-term follow-up. RESULTS Of the 127 arterial branches covered by PEDs, there were no immediate postoperative occlusions. At angiographic follow-up (mean 10 months, range 3–34.7 months), arterial side branches were occluded in 13 (15.8%) of 82 aneurysm cases and included 2 anterior cerebral arteries, 8 ophthalmic arteries, and 3 posterior communicating arteries. No cases of anterior choroidal artery occlusion were observed. Patients with branch occlusion did not experience any neurological symptoms. CONCLUSIONS In this large series, the longer-term rate of radiographic side branch arterial occlusion after coverage by a flow diverter was 15.8%. Terminal branch vessels, such as the anterior choroidal artery, remained patent in this series. The authors' series suggests that branch vessel occlusions are clinically silent and should not deter aneurysm treatment with flow diversion.

Download Full-text

EVALUATION OF ONYX HD-500 EMBOLIC SYSTEM IN THE TREATMENT OF 84 WIDE-NECK INTRACRANIAL ANEURYSMS

Neurosurgery ◽

10.1227/01.neu.0000340977.68347.51 ◽

2009 ◽

Vol 64 (5) ◽

pp. E865-E875 ◽

Cited By ~ 45

Author(s):

Ronie L. Piske ◽

Luis H. Kanashiro ◽

Eric Paschoal ◽

Celso Agner ◽

Sergio S. Lima ◽

...

Keyword(s):

Intracranial Aneurysms ◽

High Rate ◽

Anterior Circulation ◽

Complete Occlusion ◽

Aneurysm Occlusion ◽

Incomplete Occlusion ◽

Wide Neck ◽

Small Aneurysms ◽

Platinum Coils

Abstract OBJECTIVE We report our results using Onyx HD-500 (Micro Therapeutics, Inc., Irvine, CA) in the endovascular treatment of wide-neck intracranial aneurysms, which have a high rate of incomplete occlusion and recanalization with platinum coils. METHODS Sixty-nine patients with 84 aneurysms were treated. Most of the aneurysms were located in the anterior circulation (80 of 84 aneurysms), were unruptured (74 of 84 aneurysms), and were incidental. Ten presented with subarachnoid hemorrhage, and 15 were symptomatic. All aneurysms had wide necks (neck >4 mm and/or dome-to-neck ratio <1.5). Fifty aneurysms were small (<12 mm), 30 were large (12 to <25 mm) and 4 were giant. Angiographic follow-up was available for 65 of the 84 aneurysms at 6 months, for 31 of the 84 aneurysms at 18 months, and for 5 of the 84 aneurysms at 36 months. RESULTS Complete aneurysm occlusion was seen in 65.5% of aneurysms on immediate control, in 84.6% at 6 months, and in 90.3% at 18 months. The rates of complete occlusion were 74%, 95.1%, and 95.2% for small aneurysms and 53.3%, 70%, and 80% for large aneurysms at the same follow-up periods. Progression from incomplete to complete occlusion was seen in 68.2% of all aneurysms, with a higher percentage in small aneurysms (90.9%). Aneurysm recanalization was observed in 3 patients (4.6%), with retreatment in 2 patients (3.3%). Procedural mortality was 2.9%. Overall morbidity was 7.2%. CONCLUSION Onyx embolization of intracranial wide-neck aneurysms is safe and effective. Morbidity and mortality rates are similar to those of other current endovascular techniques. Larger samples and longer follow-up periods are necessary.

Download Full-text

Prolapse of the Pipeline embolization device in aneurysms: incidence, management, and outcomes

Neurosurgical FOCUS ◽

10.3171/2017.3.focus1738 ◽

2017 ◽

Vol 42 (6) ◽

pp. E16 ◽

Cited By ~ 8

Author(s):

Visish M. Srinivasan ◽

Andrew P. Carlson ◽

Maxim Mokin ◽

Jacob Cherian ◽

Stephen R. Chen ◽

...

Keyword(s):

Intracranial Aneurysms ◽

The Other ◽

Anterior Circulation ◽

Pipeline Embolization Device ◽

Giant Aneurysms ◽

Vessel Tortuosity ◽

Large And Giant Aneurysms ◽

Anterior Circulation Aneurysms

OBJECTIVEThe Pipeline embolization device (PED) is frequently used in the treatment of anterior circulation aneurysms, especially around the carotid siphon, with generally excellent results. However, the PED has its own unique technical challenges, including the occurrence of device foreshortening or migration leading to prolapse into the aneurysm. The authors sought to determine the incidence of this phenomenon, the rescue strategies, and outcomes.METHODSFour institutional databases of neuroendovascular procedures were reviewed for cases of intracranial aneurysms treated with PEDs. Patient and aneurysm data as well as angiographic imaging were reviewed for all cases involving device prolapse into the aneurysm.RESULTSA total of 413 intracranial aneurysms were treated with PEDs during the study period, by 5 neurointerventionalists. Large and giant aneurysms (≥ 2 cm) accounted for 32 of these aneurysms. Among these 32 PEDs, prolapse into the aneurysm occurred in 3 patients, with 1 of these PEDs successfully rescued and the other 2 left in situ. No patients suffered any severe complications. The 2 patients in whom the PEDs were left in situ remained on antiplatelet therapy.CONCLUSIONSThe PED may foreshorten or migrate during or after deployment, leading to prolapse into the aneurysm. This phenomenon appears to be associated with large and giant aneurysms, vessel tortuosity, short landing zones, and use of balloon angioplasty. Future study and follow-up is needed to further evaluate this phenomenon, but some of the observations and techniques described in this paper may help to prevent or salvage prolapsed devices.

Download Full-text

Remnants and Recurrences After the Use of the WEB Intrasaccular Device in Large-Neck Bifurcation Aneurysms

Neurosurgery ◽

10.1227/neu.0000000000000669 ◽

2015 ◽

Vol 76 (5) ◽

pp. 522-530 ◽

Cited By ~ 65

Author(s):

Christophe Cognard ◽

Anne Christine Januel

Keyword(s):

Single Layer ◽

Complete Occlusion ◽

Aneurysm Neck ◽

Bifurcation Aneurysm ◽

Contrast Enhanced ◽

Web Device ◽

Large Neck ◽

Shape Changes ◽

The Web

Abstract BACKGROUND: Flow disruption with the WEB technique has been developed to treat large-neck bifurcation aneurysms. OBJECTIVE: To report our anatomic angiographic results at first (3-6 months) and second (18 ± 3 months) angiographic follow-up in a series of 15 patients. METHODS: Fifteen patients (15 aneurysms) were consecutively treated in our center by 2 operators for a large-neck bifurcation aneurysm between March 2012 and February 2014. Results were evaluated by assessing WEB cage position at the aneurysm neck on angiography and high-resolution contrast-enhanced flat-panel detector computed tomography, contrast medium stagnation within the WEB and aneurysm on intraprocedural angiography, and 1-day time-of-flight magnetic resonance angiography. All aneurysms were followed up by angiography. Results at follow-up were graded as complete occlusion, neck remnant, or residual aneurysm. The 2 operators compared postprocedural and follow-up images and classified them as better, same, or worse. Subtracted images were compared in different projections to assess any WEB device compression or shape changes. RESULTS: A worsening was observed between the postprocedural and first follow-up angiography in 10 of 14 (71.5%) and in 4 of 7 (57.2%) between the first and second control angiography. Compression of the WEB cage was observed at first follow-up in 8 of 14 (57.2%) and in an additional 3 of 7 cases (42.8%) at second control. Last angiography showed complete occlusion in 1 of 14 (7.2%), neck remnant in 8 of 14 (57.2%), and residual aneurysm in 5 of 14 (35.7%) cases. CONCLUSION: This article draws attention to the risk of WEB compression and aneurysm recanalization. Future prospective studies should evaluate delayed WEB shape changes with different types of WEB devices (dual layer, single layer, single layer spherical).

Download Full-text