Mid-term anatomic results after endovascular treatment of ruptured intracranial aneurysms with Guglielmi detachable coils and Matrix coils: analysis of the CLARITY series

CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS): 12-month angiographic results of a multicenter study

BACKGROUND

The CLinical Assessment of WEB device in Ruptured aneurYSms (CLARYS) study has shown that the endovascular treatment of ruptured bifurcation aneurysms with the Woven EndoBridge (WEB) is safe and effective and provides protection against rebleeding at 1 month and 1 year. The 12-month angiographic follow-up is an important endpoint of the study.

METHODS

The CLARYS study is a prospective multicenter study conducted in 13 European centers. The study enrolled 60 patients with 60 ruptured aneurysms of the anterior and posterior circulation. The study was conducted with an independent assessment of safety outcomes and imaging.

RESULTS

Sixty patients with 60 ruptured bifurcation aneurysms to be treated with the WEB were included. Fifty-three aneurysms (88.3%) had a broad base with a dome to neck ratio <2 (mean 1.6). Of these, 46 patients were evaluated by an independent core laboratory with follow-up imaging performed at 12 months or before eventual retreatment. At 1 year, 19/46 aneurysms (41.3%) were completely occluded (Raymond-Roy grade I), 21/46 (45.7%) had a residual neck and 6/46 (13.0%) had residual aneurysm filling. Adequate occlusion was reported in 40/46 (87%) aneurysms. Six patients underwent target aneurysm retreatment.

CONCLUSIONS

The CLARYS study has previously shown that the use of the WEB in the endovascular treatment of ruptured bifurcation aneurysms provides effective protection against rebleeding with a good safety profile. The angiographic occlusion rates at 1 year reported here are comparable to those already seen in previous multicenter studies which primarily included unruptured aneurysms.

Short- and Long-Term Safety and Efficacy of Self-Expandable Leo Stents Used Alone or with Coiling for Ruptured and Unruptured Intracranial Aneurysms: A Retrospective Observational Study

To assess the efficacy and safety of the Leo stent used alone or with coiling to treat complex intracranial aneurysms (IAs) not eligible for simple or balloon-assisted coiling, this single-center retrospective study included consecutive adults with ruptured or unruptured IAs treated in 2011-2018 by stenting with or without coiling. The indication for stenting was IA complexity precluding simple or balloon-assisted coiling. Extensive data on the patients, IAs, antiplatelet treatments, procedures, and outcomes over the first 36 months were collected. Risk factors for early complications (univariate analysis) and delayed ischemia (multivariate analysis) were sought. We include 64 patients with 66 IAs. The procedural success rate was 65/66 (98.5%). Obliteration was Raymond Roy class I or II for 85% of IAs. Six patients died including four of the 12 patients presenting with subarachnoid hemorrhage, which was the only significant risk factor for early major complications. At 1 month, 45/64 (69%) had no disabilities. No rebleeding was reported. Ischemia was detected by routine MRI in 20 (35%) of the 57 patients with long-term data and was asymptomatic in 14. The stent-within-a-stent configuration was the only independent risk factor for ischemia. The Leo stent used alone or with coils to manage challenging IAs was associated with a high procedural success rate and complete or nearly complete IA obliteration of 85% of IAs. The high frequency of ischemia is ascribable to our use of routine serial MRI. In patients with bleeding, the Leo stent was associated with an excess risk of early, major, intracranial complications, as compared to patients without bleeding. Long-term follow-up was marked by the occurrence of ischemic events in the vascular territory of the stent, mostly silent.

The SMART Registry: Long-Term Results on the Utility of the Penumbra SMART COIL System for Treatment of Intracranial Aneurysms and Other Malformations

Introduction: Penumbra SMART COIL® (SMART) System is a novel generation embolic coil with varying stiffness. The study purpose was to report real-world usage of the SMART System in patients with intracranial aneurysms (ICA) and non-aneurysm vascular lesions. Materials and Methods: The SMART Registry is a post-market, prospective, multicenter registry requiring ≥75% Penumbra Coils, including SMART, PC400, and/or POD coils. The primary efficacy endpoint was retreatment rate at 1-year and the primary safety endpoint was the procedural device-related serious adverse event rate. Results: Between June 2016 and August 2018, 995 patients (mean age 59.6 years, 72.1% female) were enrolled at 68 sites in the U.S. and Canada. Target lesions were intracranial aneurysms in 91.0% of patients; 63.5% were wide-neck and 31.8% were ruptured. Adjunctive devices were used in 55.2% of patients. Mean packing density was 32.3%. Procedural device-related serious adverse events occurred in 2.6% of patients. The rate of immediate post-procedure adequate occlusion was 97.1% in aneurysms and the rate of complete occlusion was 85.2% in non-aneurysms. At 1-year, the retreatment rate was 6.8%, Raymond Roy Occlusion Classification (RROC) I or II was 90.0% for aneurysms, and Modified Rankin Scale (mRS) 0-2 was achieved in 83.1% of all patients. Predictors of 1-year for RROC III or retreatment (incomplete occlusion) were rupture status (P < 0.0001), balloon-assisted coiling (P = 0.0354), aneurysm size (P = 0.0071), and RROC III immediate post-procedure (P = 0.0086) in a model that also included bifurcation aneurysm (P = 0.7788). Predictors of aneurysm retreatment at 1-year was rupture status (P < 0.0001). Conclusions: Lesions treated with SMART System coils achieved low long-term retreatment rates. Clinical Trial Registration: https://www.clinicaltrials.gov/, identifier NCT02729740.

The Relationships between Anatomical Factors and Treatment Procedures for the Endovascular Treatment of Anterior Communicating Artery Aneurysms

Objective

Endovascular treatment of anterior communicating artery aneurysms is difficult due to their complex anatomical structure. We retrospectively analyzed the relationships among the anatomical features, initial microcatheter positions, and initial occlusion outcomes.

Methods

In all, 66 cases were treated at our hospital. We investigated the relationships among the anatomical features of the aneurysm and A1 segment of the anterior cerebral artery (ACA), treatment procedures, and initial occlusion outcomes. We divided the initial microcatheter positions into greater and lesser curvatures based on the curvature from A1 to the aneurysm, and evaluated the outcomes.

Results

In total, 54 out of 66 patients (82%) achieved complete obliteration (CO) or had residual neck (RN) aneurysms, and 12 had residual aneurysms (RAs: 18%). Neck diameters and superior position aneurysms were correlated with initial occlusion outcomes in the multivariate analysis. The relationship between initial occlusion outcomes and initial microcatheter positions in superior position aneurysms (37 patients) was then examined. Eleven out of 26 patients (42.3%) had residual aneurysms at the greater curvature microcatheter position, whereas no residual aneurysms were detected at the lesser curvature microcatheter position. The A1 angle was not correlated with the outcomes.

Conclusion

Wide-necked aneurysms and superior position aneurysms were identified as factors leading to incomplete occlusion in the endovascular treatment of anterior communicating artery aneurysms. The microcatheter position at the greater curvature in superior position aneurysms was a factor for incomplete occlusion. This suggests that guiding the microcatheter to the lesser curvature position of A1 is important in the treatment of superior position aneurysms.

The Distribution and Role of M1 and M2 Macrophages in Aneurysm Healing after Platinum Coil Embolization

BACKGROUND AND PURPOSE

Impairment of macrophage polarization from a proinflammatory macrophage type 1 (M1) population to an anti-inflammatory macrophage type 2 (M2) population is a hallmark of poor wound healing. In this study, we aimed to evaluate the distribution of M1 and M2 macrophages and to analyze their association with healing in aneurysms embolized by endovascular coiling.

MATERIALS AND METHODS

Elastase-induced aneurysms were created in female rabbits and subsequently embolized with platinum coils. Aneurysm occlusions were evaluated with angiographic imaging at 1 (n = 6), 3 (n = 5), or 6 (n = 6) months. Aneurysm tissues were harvested for histologic analysis, quantification of M1 and M2 macrophages by immunofluorescence, and collagen deposition determined by Masson trichrome staining. Histologic grading of aneurysm healing was also performed. Untreated aneurysms were used as controls (n = 6).

RESULTS

The M1 macrophage population was highest at 1 month posttreatment, progressively decreasing at 3 and 6 months. The M2 macrophage population progressively increased at 3 and 6 months posttreatment. The highest collagen deposition was at 6 months posttreatment. We found a moderate-to-weak direct correlation between the percentage of M2 macrophages and collagen deposition, as well as total histologic scores overall, and a strongly positive direct correlation between the percentage of M2 macrophages and total histologic scores at 6 months posttreatment.

CONCLUSIONS

Our data support the direct correlation between M2 macrophage polarization and healing in aneurysm tissues. Our results show a positive relationship between M2 macrophage populations and total histologic scores at later stages of healing after endovascular coiling. We conclude that interventions aimed at stimulating M2 macrophage expression locally may improve aneurysm healing after coil embolization.

Off-Label Use of the WEB Device

OBJECTIVE

We present our initial experience with the off-label use of the Woven EndoBridge (WEB) device.

METHODS

We performed a retrospective study from 2 institutions of patients with intracranial aneurysms who underwent treatment with the WEB device alone or in conjunction with stenting and/or coiling in an off-labeled location.

RESULTS

Eleven patients with 12 aneurysms were included. Four (30.8%) aneurysms presented ruptured. Off-labeled locations included 3 aneurysms in the posterior communicating artery, 3 in the supraclinoid ophthalmic artery, 2 in the pericallosal artery, 2 in the posterior inferior cerebellar artery, 1 at the vertebrobasilar junction, and 1 in the cavernous internal carotid artery. Mean dome-to-neck ratio was 1.91 ± 0.9. Average duration of the procedure was 63.9 ± 29.6 minutes. Femoral route was used in 61.5%, and radial access in 48.5% of cases. Five procedures (41.7%) were performed under monitored anesthesia care. We had 1.33 attempts per aneurysm. WEB embolization was supplemented with coiling in 2 cases (16.67%) and stenting in 1 case (8.3%). Based on the O'Kelly-Marotta ("OKM") grading scale, we report a rate of 0% for grade 1, 33.3% for grade 2, and 33.3% for grade 3. Postprocedural occlusion was complete in 4 (33.3%) and adequate in 8 (66.6%) patients. No procedure-related deaths or symptomatic complications were reported.

CONCLUSIONS

The WEB device was successfully deployed in off-labeled locations, including posterior communicating artery, ophthalmic artery, and pericallosal aneurysms. The efficacy of this usage must be evaluated in multicenter prospective studies, but our preliminary results are promising. Correct characterization of the aneurysm size/morphology, as well as awareness of possible adjunct treatments, are crucial for successful intervention.

Diverse Use of the WEB Device: A Technical Note on WEB Stenting and WEB Coiling of Complex Aneurysms

The Woven EndoBridge (WEB) device, an intrasaccular flow-diverter that does not require long-term antiplatelet use, has recently emerged as an alternative to embolize complex intracranial aneurysms; however, there are limitations to the WEB device. First, it does not immediately secure the aneurysm in most subarachnoid hemorrhage cases. Second, it may not be suitable for embolization of wide-neck aneurysms with an unfavorable aspect ratio. To overcome these limitations, we have used the WEB device in conjunction with stenting and/or coiling. Here, we present a technical note with an illustrated case series and provide a detailed step-by-step description on how the WEB device can be used in adjunct to coiling and/or stenting to achieve successful angiographic results. Accurate sizing of the WEB device before deployment is critical. Larger case series are required to further assess the safety and success of these combined techniques.

[Place of interventional neuroradiology in the prevention of hemorrhagic stroke]

The risk of bleeding of unruptured aneurysms is increasing with aneurysm size. Small unruptured aneurysms can be treated conservatively with a regular MRI/MRA follow-up to detect a potential increase in size. If coiling is still the main endovascular technique for the treatment of unruptured aneurysms, several other techniques are now available including stent-assisted coiling, flow diversion, and flow disruption. After ARUBA study, there is no recommendation to treat unruptured brain AVMs. According to their hemorrhagic risk, dural arteriovenous fistulas with cortical venous drainage have to be treated, generally by endovascular approach through an arterial route.

Initial experience and one-year follow-up with Neuroform Atlas Stent System for the treatment of brain aneurysms

INTRODUCTION

The Neuroform Atlas Stent System is a recently introduced modification of the original Neuroform Stent System consisting of a hybrid design with open and closed cells. Initial experience, technical considerations and treatment outcomes including 1-year follow-up using the Atlas stent in combination with coil embolization are reported.

MATERIAL AND METHODS

Thirty patients with 30 unruptured aneurysms were treated with stent reconstruction. Immediate, 4-month and 12-month post-treatment angiography and clinical assessment were performed.

DISCUSSION

In 29 cases, the stents were delivered and positioned without difficulty in deployment. Technical complications occurred in one patient related to advancement of the stent during delivery. One procedure-related clinical complication occurred with no permanent neurological deficit. On immediate post-treatment angiography, 29 of 30 aneurysms showed Raymond Class I or Class II occlusion. At 1-year follow-up, all 30 patients were clinically stable and 18 of 30 aneurysms showed Raymond Class I complete occlusion. Retreatment was performed in two patients with residual aneurysm.

CONCLUSIONS

The Atlas stent is technically safe and simple to implant and has a low thrombogenic potential. We experienced fewer problems associated with deployment and implantation, thromboembolic complications and hemorrhagic events compared with other types of stents, including braided stents. However, because of its low thrombogenic potential, partially occluded aneurysms or those with aneurysm remnants do not progress to complete occlusion.

Long-term results of middle cerebral artery aneurysm clipping in the Barrow Ruptured Aneurysm Trial

Objective

A direct comparison of endovascular versus microsurgical treatment of ruptured middle cerebral artery (MCA) aneurysms in randomized trials is lacking. As endovascular treatment strategies continue to evolve, the number of reports of endovascular treatment of these lesions is increasing. Herein, the authors report a detailed post hoc analysis of ruptured MCA aneurysms treated by microsurgical clipping from the Barrow Ruptured Aneurysm Trial (BRAT).

Methods

The cases of patients enrolled in the BRAT who underwent microsurgical clipping for a ruptured MCA aneurysm were reviewed. Characteristics of patients and their clinical outcomes and long-term angiographic results were analyzed.

Results

Fifty patients underwent microsurgical clipping of a ruptured MCA aneurysm in the BRAT, including 21 who crossed over from the endovascular treatment arm. Four patients with nonsaccular (e.g., dissecting, fusiform, or blister) aneurysms were excluded, leaving 46 patients for analysis. Most (n = 32; 70%) patients presented with a Hunt and Hess grade II or III subarachnoid hemorrhage, with a high prevalence of intraparenchymal blood (n = 23; 50%), intraventricular blood (n = 21; 46%), or both. At the last follow-up (up to 6 years after treatment), clinical outcomes were good (modified Rankin Scale score 0–2) in 70% (n = 19) of 27 Hunt and Hess grades I–III patients and in 36% (n = 4) of 11 Hunt and Hess grade IV or V patients. There were no instances of rebleeding after the surgical clipping of aneurysms in this series at the time of last clinical follow-up.

Conclusions

Microsurgical clipping of ruptured MCA aneurysms has several advantages over endovascular treatment, including durability over time. The authors report detailed outcome data of patients with ruptured MCA aneurysms who underwent microsurgical clipping as part of a prospective, randomized trial. These results should be used for comparison with future endovascular and surgical series to ensure that the best results are being achieved for patients with ruptured MCA aneurysms.

The LUNA aneurysm embolization system for intracranial aneurysm treatment: short-term, mid-term and long-term clinical and angiographic results

BACKGROUND AND PURPOSE

Intrasaccular aneurysm flow disruption represents an emerging endovascular approach to treat intracranial aneurysms. The purpose of this study was to determine the clinical and angiographic outcomes of using the LUNA aneurysm embolization system (AES) for treatment of intracranial aneurysms.

MATERIALS AND METHODS

The LUNA AES Post-Market Clinical Follow-Up study is a prospective, multicenter, single-arm study that was designed to evaluate device safety and efficacy. Bifurcation and sidewall aneurysms were included. Aneurysm occlusion was assessed using the Raymond-Roy classification scale. Disability was assessed using the Modified Rankin Scale (mRS). Morbidity was defined as mRS >2 if baseline mRS ≤2, increase in mRS of 1 or more if baseline mRS >2, or mRS >2 if aneurysm was ruptured at baseline. Clinical and angiographic follow-up was conducted at 6, 12 and 36 months.

RESULTS

Sixty-three subjects with 64 aneurysms were enrolled. Most aneurysms were unruptured (60/63 (95.2%)); 49 were bifurcation or terminal (49/64 (76.6%)). Mean aneurysm size was 5.6±1.8 mm (range, 3.6-14.9 mm), and mean neck size was 3.8±1.0 mm (range, 1.9-8.7 mm). Though immediate postoperative adequate occlusion was low (11/63, 18%), adequate occlusion was achieved in 78.0% (46/59) and 79.2% (42/53) of the aneurysms at 12 months and 36 months, respectively. Four patients were retreated by the 12-month follow-up (4/63 (6.3%)) and three patients were retreated by the 36-month follow-up (3/63 (4.8%)). There were two major strokes (2/63 (3.2%)), one minor stroke (1/63 (1.6%)) and three incidents of intracranial hemorrhage in two subjects (2/63 (3.2%)) prior to the 12-month follow-up. There was one instance of mortality (1/63, 1.6%). Morbidity was 0% (0/63) and 1.8% (1/63) at the 12-month and 36-month follow-ups, respectively.

CONCLUSIONS

LUNA AES is safe and effective for the treatment of bifurcation and sidewall aneurysms.

CLINICAL TRIAL REGISTRATION

ISRCTN72343080; Results.

Occlusion rates of intracranial aneurysms treated with the Pipeline embolization device: the role of branches arising from the sac

OBJECTIVE

The aim of this study was to compare the clinical and angiographic outcomes of intracranial aneurysms with and without branches arising from the sac after Pipeline embolization device (PED) treatment.

METHODS

This retrospective 2-center comparative study included 116 patients with 157 aneurysms that were treated with PEDs. Aneurysms were divided into 2 groups: one group had branches arising from the sac and the other group did not. Study end points included total aneurysm occlusion assessed by angiography at 6 and 12 months, death or stroke, technical complications, in-stent stenosis, patency of covered branches, and transient ischemia.

RESULTS

One hundred fifty-one aneurysms (96%) were located in the internal carotid artery. A branch arising from the sac was observed in 26 aneurysms. Complete occlusion was found in 120 of 156 aneurysms at 6 months (76.92% [95% CI 69.71%-82.84%]) and in 136 of 155 aneurysms at 12 months (87.74% [95% CI 81.28%-92.27%]). Total occlusion was more frequently observed in the group without a branch arising from the sac (84% vs 40% at 6 months, p < 0.001; 93.10% vs 60% at 1 year, p < 0.001). There were 4 (3.45% [95% CI 1.11%-9.12%]) cases of death or major stroke. Amaurosis fugax occurred in 3 patients. One patient experienced worsening of mass effect after treatment. No occlusion of branches arising from the aneurysm was observed. In-stent stenosis greater than 50% was observed in 1 case.

CONCLUSIONS

Aneurysms treated with PEDs are less likely to be totally occluded if they have a branch arising from the sac than are aneurysms without these branches.

Safety and efficacy of aneurysm treatment with WEB: results of the WEBCAST study

OBJECT

WEB is an innovative intrasaccular treatment for intracranial aneurysms. Preliminary series have shown good safety and efficacy. The WEB Clinical Assessment of Intrasaccular Aneurysm Therapy (WEBCAST) trial is a prospective European trial evaluating the safety and efficacy of WEB in wide-neck bifurcation aneurysms.

METHODS

Patients with wide-neck bifurcation aneurysms for which WEB treatment was indicated were included in this multicentergood clinical practices study. Clinical data including adverse events and clinical status at 1 and 6 months were collected and independently analyzed by a medical monitor. Six-month follow-up digital subtraction angiography was also performed and independently analyzed by a core laboratory. Success was defined at 6 months as complete occlusion or stable neck remnant, no worsening in angiographic appearance from postprocedure, and no retreatment performed or planned.

RESULTS

Ten European neurointerventional centers enrolled 51 patients with 51 aneurysms. Treatment with WEB was achieved in 48 of 51 aneurysms (94.1%). Adjunctive implants (coils/stents) were used in 4 of 48 aneurysms (8.3%). Thromboembolic events were observed in 9 of 51 patients (17.6%), resulting in a permanent deficit (modified Rankin Scale [mRS] Score 1) in 1 patient (2.0%). Intraoperative rupture was not observed. Morbidity (mRS score > 2) and mortality were 2.0% (1 of 51 patients, related to rupture status on entry to study) and 0.0% at 1 month, respectively. Success was achieved at 6 months in 85.4% of patients treated with WEB: 23 of 41 patients (56.1%) had complete occlusion, 12 of 41 (29.3%) had a neck remnant, and 6 of 41 (14.6%) had an aneurysm remnant.

CONCLUSIONS

The WEBCAST study showed good procedural and short-term safety of aneurysm treatment with WEB and good 6-month anatomical results.

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)

BACKGROUND

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

OBJECTIVE

To report clinical and anatomical results of the WEB treatment in the cumulated population of WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm) and French Observatory series.

METHODS

WEBCAST and French Observatory are single-arm, prospective, multicenter, Good Clinical Practice studies dedicated to the evaluation of WEB treatment. Ruptured and unruptured bifurcation aneurysms located in the basilar artery, middle cerebral artery, anterior communicating artery, and internal carotid artery terminus were included in both studies. Clinical data were independently evaluated. Postoperative, 6-month (in WEBCAST), and 1-year aneurysm occlusion was independently evaluated with a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.

RESULTS

The cumulated population was 113 patients (74 female, 65.5%) 33 to 74 years of age with 114 aneurysms with a mean neck size of 5.6 mm. There was no mortality at 1 month, and morbidity was 2.7%. A statistically significant difference in the rate of occurrence of thromboembolic events was observed between the use of any antiplatelet agent and the use of no antiplatelet agent (P < .001). At 1 year, complete aneurysm occlusion was observed in 56.0%, neck remnant in 26.0%, and aneurysm remnant in 18.0%. Worsening of aneurysm occlusion between the procedure and 12 months was observed in 2.0% and between 6 months and 1 year in 7.1%.

CONCLUSION

The analysis in this large cumulated population of studies confirms favorable safety and efficacy of WEB treatment.

Retrospective Analysis of Delayed Intraparenchymal Hemorrhage after Flow-Diverter Treatment: Presentation of a Retrospective Multicenter Trial

BACKGROUND AND PURPOSE

Intracranial aneurysm treatment with flow diverters has shown satisfying results in terms of aneurysm occlusion, and while some cases of delayed intraparenchymal hemorrhage have been described, no systematic analysis of the risk factors affecting its occurrence has been conducted in a large series of patients. This retrospective analysis of delayed intraparenchymal hemorrhage after flow-diverter treatment is a multicenter, retrospective study using a large series of treated patients to analyze factors affecting the occurrence of delayed intraparenchymal hemorrhage.

MATERIALS AND METHODS

Patients treated with flow diverters and presenting with delayed intraparenchymal hemorrhage were included from December 2007 to December 2014 in 7 participating centers in France. Patient and aneurysm characteristics were recorded as were characteristics of bleeding (size, lateralization, and time to bleed), treatment, and clinical outcome after 1, 3, and 6 months.

RESULTS

Delayed intraparenchymal hemorrhage occurred in 11 patients between 1 and 21 days after the procedure. In 10 of these patients, hemorrhages were ipsilateral to the treated aneurysms. Five of the 11 underwent surgery, and 9 of the 11 had good clinical outcomes at 6 months (mRS ≤2).

CONCLUSIONS

The pathogenesis of delayed intraparenchymal hemorrhage occurring after flow-diverter treatment remains unclear. The multidisciplinary management of delayed intraparenchymal hemorrhage yields a relatively low morbidity-mortality rate compared with the initial clinical presentation.

Differences in tissue proliferation and maturation between Matrix2 and bare platinum coil embolization in experimental swine aneurysms

BACKGROUND AND PURPOSE

Recanalization of post-embolization cerebral aneurysms remains a serious problem that influences treatment outcomes. Matrix2 is a bioactive, bio-absorbable, detachable coil that was developed to reduce the risk of recanalization. We examined the short-term efficacy of the Matrix2 coil system, and evaluated the temporal profile of tissue proliferation in a swine experimental aneurysm model compared with the bare platinum (BP) coil.

MATERIALS AND METHODS

Thirty-six experimental aneurysms were created in 18 swine. All aneurysms were tightly packed with Matrix2 or BP coils. Comparative histologic and morphologic analyses were undertaken 1, 2 and 4 weeks post-embolization.

RESULTS

Endothelial-like cells were observed partially lining the aneurysmal opening one week post-embolization with both coil types. At two and four weeks post-embolization, the aneurysms treated with Matrix2 coils had more extensive areas of organized thrombus than those packed with BP coils, but the numbers of functional proliferating endothelial cells identified by immunohistochemistry in the tissue were broadly comparable between the groups. Moreover, morphological analysis suggested there were more mature endothelial cells in aneurysms treated with bare platinum rather than Matrix2 coils.

CONCLUSIONS

Our results indicate that aneurysms embolized with Matrix2 coils build thicker scaffolds for endothelialization, but this is not necessarily evidence of earlier tissue proliferation and maturation than those embolized with BP coils. Matrix2 coils may not be superior to BP coils for preventing aneurysmal recanalization after endovascular treatment of cerebral aneurysms.

Rebleeding of a neck remnant in a case of ruptured aneurysm initially treated with coils

The follow-up and indications for retreatment of intracranial aneurysms treated endovascularly are still a matter of debate. We report the case of a patient with a ruptured aneurysm who was treated twice with coils and regularly followed up with MRI/MR angiography which showed a neck remnant that finally rebled.

Rebleeding of a neck remnant in a case of ruptured aneurysm initially treated with coils

The follow-up and indications for retreatment of intracranial aneurysms treated endovascularly are still a matter of debate. We report the case of a patient with a ruptured aneurysm who was treated twice with coils and regularly followed up with MRI/MR angiography which showed a neck remnant that finally rebled.

WEB intrasaccular flow disruptor-prospective, multicenter experience in 83 patients with 85 aneurysms

BACKGROUND AND PURPOSE

The safety and efficacy of WEB flow disruption have been analyzed in small, retrospective series. The object of this study was to evaluate the safety and efficacy of WEB flow disruption in a large, multicenter, prospectively collected population.

MATERIALS AND METHODS

Data from all patients treated with the WEB-DL device between June 2011 and October 2013 in 11 French neurointerventional centers were prospectively collected and retrospectively analyzed. Complications occurring during and after treatment were analyzed as well as morbidity and mortality at 1 month. Aneurysm occlusion status at the last follow-up was analyzed.

RESULTS

Eighty-three patients with 85 aneurysms were included in this series. Technical success was achieved in 77 patients with 79 aneurysms (92.9%). Periprocedural complications were observed in 9 patients (10.8%), leading to permanent neurologic deficits in 3 (3.9%). Morbidity and mortality at 1 month were 1.3% and 0.0%, respectively. Angiographic follow-up was performed for 65/79 aneurysms (82.3%) 3-24 months after treatment (mean, 5.3 months). Complete aneurysm occlusion was observed in 37/65 aneurysms (56.9%); neck remnant, in 23/65 (35.4%); and aneurysm remnant, in 5/65 (7.7%).

CONCLUSIONS

In this large prospective series of patients, WEB flow disruption was a safe and efficient technique.

Analysis of recanalization after endovascular treatment of intracranial aneurysm (ARETA trial): presentation of a prospective multicenter study

PURPOSE

Aneurysm recanalization is a main concern after endovascular treatment of intracranial aneurysms. But to date, no systematic analysis of the risk factors affecting its occurrence has been conducted in a large series of patients. Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) is a multicenter, prospective trial whose aim is to collect a large series of patients treated endovascularly to analyze factors affecting aneurysm recanalization.

STUDY DESIGN

Patients with ruptured or unruptured aneurysms treated endovascularly will be enrolled from December 2013 to December 2014 in 19 participating centers in France. Patient and aneurysm characteristics will be recorded as well as the type of endovascular treatment and the occurrence of procedural or post-procedural complications. Post-procedural and follow-up imaging after one year will be analyzed independently by two readers using a 3-grade scale (complete occlusion, neck remnant, or aneurysm remnant). The progression of aneurysm occlusion will also be evaluated (improved, stable, or worsened). Aneurysm occlusion at one year and progression of aneurysm occlusion will be analyzed in light of patient, aneurysm, and treatment factors.

CONCLUSION

ARETA is a large, prospective, multicenter trial designed to assess predictive factors of aneurysm recanalization after endovascular treatment of intracranial aneurysms.

In vivo response to an implanted shape memory polyurethane foam in a porcine aneurysm model

Cerebral aneurysms treated by traditional endovascular methods using platinum coils have a tendency to be unstable, either due to chronic inflammation, compaction of coils, or growth of the aneurysm. We propose to use alternate filling methods for the treatment of intracranial aneurysms using polyurethane-based shape memory polymer (SMP) foams. SMP polyurethane foams were surgically implanted in a porcine aneurysm model to determine biocompatibility, localized thrombogenicity, and their ability to serve as a stable filler material within an aneurysm. The degree of healing was evaluated via gross observation, histopathology, and low vacuum scanning electron microscopy imaging after 0, 30, and 90 days. Clotting was initiated within the SMP foam at time 0 (<1 h exposure to blood before euthanization), partial healing was observed at 30 days, and almost complete healing had occurred at 90 days in vivo, with minimal inflammatory response.

Bioactive versus bare platinum coils in the treatment of intracranial aneurysms: the MAPS (Matrix and Platinum Science) trial

BACKGROUND AND PURPOSE

The ability of polymer-modified coils to promote stable aneurysm occlusion after endovascular treatment is not well-documented. Angiographic aneurysm recurrence is widely used as a surrogate for treatment failure, but studies documenting the correlation of angiographic recurrence with clinical failure are limited. This trial compares the effectiveness of Matrix(2) polyglycolic/polylactic acid biopolymer-modified coils with bare metal coils and correlates the angiographic findings with clinical failure (ie, target aneurysm recurrence), a composite end point that includes any incident of posttreatment aneurysm rupture, retreatment, or unexplained death.

MATERIALS AND METHODS

This was a multicenter randomized noninferiority trial with blinded end point adjudication. We enrolled 626 patients, divided between Matrix(2) and bare metal coil groups. The primary outcome was target aneurysm recurrence at 12 ± 3 months.

RESULTS

At 455 days, at least 1 target aneurysm recurrence event had occurred in 14.6% of patients treated with bare metal coils and 13.3% of Matrix(2) (P = .76, log-rank test) patients; 92.8% of target aneurysm recurrence events were re-interventions for aneurysms that had not bled after treatment, and 5.8% of target aneurysm recurrence events resulted from hemorrhage or rehemorrhage, with or without retreatment. Symptomatic re-intervention occurred in only 4 (0.6%) patients. At 455 days, 95.8% of patients with unruptured aneurysms and 90.4% of those with ruptured aneurysms were independent (mRS ≤ 2). Target aneurysm recurrence was associated with incomplete initial angiographic aneurysm obliteration, presentation with rupture, and a larger aneurysmal dome and neck size.

CONCLUSIONS

Tested Matrix(2) coils were not inferior to bare metal coils. Endovascular coiling of intracranial aneurysms was safe, and the rate of technical success was high. Target aneurysm recurrence is a promising clinical outcome measure that correlates well with established angiographic measurements.

Endovascular treatment with flow diverters of recanalized and multitreated aneurysms initially treated by endovascular approach

PURPOSE

To evaluate the feasibility, safety and efficacy of endovascular treatment with flow diverters in patients with recanalized and multitreated aneurysms in a retrospective, multicenter, single-arm study.

METHODS

The study included 29 patients with 29 recanalized aneurysms who were treated by flow diverters (Silk or Pipeline devices). Pre- and post-procedural complications and morbidity and mortality rates were evaluated and functional outcomes (modified Rankin Score (mRS)) at 1 month (short-term) and 3-4 months (mid-term) were compared with preoperative mRS (before the procedure). Mid-term angiographic follow-up was performed assessing aneurysmal occlusion by the Montreal scale (complete occlusion, neck remnant, aneurysm remnant).

RESULTS

Placement of the flow diverters was achieved in all patients. Two misdeployments of the flow diverters necessitated balloon dilation in two patients, which was associated with stent delivery in one patient. Permanent morbidity related to treatment was 6.9% (2/29), transient morbidity was 10.3% (3/29) and there were no deaths resulting from the treatment. One patient died from a myocardial infarct 4 weeks after the procedure. 25/29 patients (86.2%) had a good final functional outcome, 26/29 (89.7%) had an unchanged functional outcome and 2/29 patients (6.9%) had clinical worsening. Angiographic follow-up showed complete occlusion in 17/28 patients (60.7%), neck remnants in 6/28 patients (21.4%) and residual aneurysms in 5/28 (17.9%).

CONCLUSIONS

Flow diverter placement is feasible and safe in patients with recanalized and multitreated aneurysms. The procedure is associated with a high percentage of good functional outcomes as well as good mid-term anatomical results (82.1%).

Endovascular methods for the treatment of intracranial cerebral aneurysms

This article briefly discusses the clinical features, natural history, and epidemiology of intracranial cerebral aneurysms, along with current diagnostic imaging techniques for their detection. The main focus is on the basic techniques used in endovascular coiling of ruptured and nonruptured saccular intracranial cerebral aneurysms. After a discussion of each technique, a short review of the results of each form of treatment is given, concentrating on reported large case series. Specific complications related to the endovascular treatment of saccular intracranial aneurysms are then discussed.

[Neuroimaging follow-up of cerebral aneurysms treated with endovascular techniques]

There are no specific recommendations in clinical guidelines about the best time, imaging tests, or intervals for following up patients with intracranial aneurysms treated with endovascular techniques. We reviewed the literature, using the following keywords to search in the main medical databases: cerebral aneurysm, coils, endovascular procedure, and follow-up. Within the Cerebrovascular Disease Group of the Spanish Society of Neuroradiology, we aimed to propose recommendations and an orientative protocol based on the scientific evidence for using neuroimaging to monitor intracranial aneurysms that have been treated with endovascular techniques. We aimed to specify the most appropriate neuroimaging techniques, the interval, the time of follow-up, and the best approach to defining the imaging findings, with the ultimate goal of improving clinical outcomes while optimizing and rationalizing the use of available resources.

Coil type does not affect angiographic follow-up outcomes of cerebral aneurysm coiling: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Previous studies varied in their conclusions about the superiority of second-generation coils compared with bare platinum. In this systematic review and meta-analysis, we assessed differences in reported unfavorable angiographic outcomes of cerebral aneurysms treated with coil embolization as a function of coil type.

MATERIALS AND METHODS

This systematic review covered 1999-2011 through the use of Ovid MEDLINE and EMBASE. Search terms were "subarachnoid hemorrhage," "intracranial aneurysms," "endovascular treatment," and "coiling." Inclusion criteria were studies reporting >50 aneurysms with imaging follow-up. We defined "unfavorable angiographic outcome" as either "recanalization," <90% occlusion, or "incomplete occlusion" at follow-up. Rates of unfavorable outcomes were pooled through the use of random effects models and compared across various coil types. Multivariate random effects meta-regression models were used to further explore the differences in outcomes related to coil type.

RESULTS

We included 82 studies, comprising 90 patient cohorts, among which, 65 (72%) used bare platinum coils, 8 (8.9%) used Matrix, 11 (12%) used HydroCoil, and 6 (6.7%) used Cerecyte. The overall unfavorable outcome rate was 19% (95% CI: 17%,21%). Unfavorable outcome rates were 20% (95% CI: 17%, 22%) for bare platinum coils, 23% (95% CI: 16%, 29%) for Matrix, 15% (95% CI: 9%, 21%) for HydroCoil, and 15% (95% CI: 7%, 23%) for Cerecyte, respectively. The difference in unfavorable outcome rates among the various coil types was not statistically significant after adjusting for baseline characteristics, including aneurysm size, rupture status, and follow-up duration.

CONCLUSIONS

The rate of unfavorable angiographic outcomes was not statistically different across the major approved coil types. The quality of the evidence, however, remains low because of high heterogeneity, small sample size, and potential publication bias.

Differences in the angiographic evaluation of coiled cerebral aneurysms between a core laboratory reader and operators: results of the Cerecyte Coil Trial

BACKGROUND AND PURPOSE

Independent evaluation of angiographic images is becoming widely applied in the assessment of treatment outcomes of cerebral aneurysms. In the current study, we assessed the agreement between an independent core laboratory and the operators regarding angiographic appearance in a recent randomized, controlled trial.

MATERIALS AND METHODS

Data were derived from the Cerecyte Coil Trial. Angiographic images of each coiled aneurysm, taken immediately after embolization and at 5- to 7-month follow-up, were evaluated by the operator at the treating center and by an independent neuroradiologist at the core laboratory. For the purpose of this study, images were interpreted on a 3-point scale to provide uniformity for analysis; grade 1: complete occlusion, grade 2: neck remnant; and grade 3: sac filling. "Unfavorable angiographic appearance" was defined as grade 3 at follow-up or interval worsening of grade between the 2 time points.

RESULTS

The study included 434 aneurysms. Immediately after embolization, grade 3 was reported by operators in 39 (9%) compared with 52 (12%) by the core laboratory (P = .159). On follow-up, grade 3 was reported by operators in 44 (10%) compared with 81 (19%) by the core laboratory (P < .0001). Overall, operators noted unfavorable angiographic appearance in 78 (18%) compared with 134 (31%) by the core laboratory (P < .0001). At every time point, agreement between the core laboratory and the operators was slight.

CONCLUSIONS

Unfavorable angiographic appearance was noted almost twice as frequently by an independent core laboratory as compared with the operators. Planning of trials and interpretation of published studies should be done with careful attention to the mode of angiographic appearance interpretation.

Endovascular treatment of ruptured intracranial aneurysms

Aneurysmal subarachnoid hemorrhage (SAH) is a catastrophic neurologic event. Early triage of patients with SAH should include cardiopulmonary stabilization, neurologic assessment, and imaging. Conventional angiography with 3-dimensional rendering is necessary to accurately assess aneurysm morphology and location, so that treatment can be planned appropriately. Current evidence suggests that coil embolization can be beneficial for aneurysms amenable to endovascular treatment. The use of remodeling techniques has expanded the range of aneurysms treatable by endovascular means. Balloon remodeling can be a powerful technique for treating ruptured aneurysms with unfavorable morphology. However, stent-assisted technique is associated with significantly higher complication rates in ruptured aneurysms and requires dual antiplatelet agents, and should therefore be considered with great caution for ruptured aneurysms. Complications of ruptured aneurysm embolization include aneurysm perforation, which should be addressed with immediate occlusion of the aneurysm, and thromboembolism, which can be managed most effectively with glycoprotein IIb/IIIa inhibitors.

The Barrow Ruptured Aneurysm Trial: 3-year results

OBJECT

The authors report the 3-year results of the Barrow Ruptured Aneurysm Trial (BRAT). The objective of this ongoing randomized trial is to compare the safety and efficacy of microsurgical clip occlusion and endovascular coil embolization for the treatment of acutely ruptured cerebral aneurysms and to compare functional outcomes based on clinical and angiographic data. The 1-year results have been previously reported.

METHODS

Two-hundred thirty-eight patients were assigned to clip occlusion and 233 to coil embolization. There were no anatomical exclusions. Crossovers were allowed based on the treating physician's determination, but primary outcome analysis was based on the initial assignment to treatment modality. Patient outcomes were assessed independently using the modified Rankin Scale (mRS). A poor outcome was defined as an mRS score>2. At 3 years' follow-up 349 patients who had actually undergone treatment were available for evaluation. Of the 170 patients who had been originally assigned to coiling, 64 (38%) crossed over to clipping, whereas 4 (2%) of 179 patients assigned to surgery crossed over to clipping.

RESULTS

The risk of a poor outcome in patients assigned to clipping compared with those assigned to coiling (35.8% vs 30%) had decreased from that observed at 1 year and was no longer significant (OR 1.30, 95% CI 0.83-2.04, p=0.25). In addition, the degree of aneurysm obliteration (p=0.0001), rate of aneurysm recurrence (p=0.01), and rate of retreatment (p=0.01) were significantly better in the group treated with clipping compared with the group treated with coiling. When outcomes were analyzed based on aneurysm location (anterior circulation, n=339; posterior circulation, n=69), there was no significant difference in the outcomes of anterior circulation aneurysms between the 2 assigned groups across time points (at discharge, 6 months, 1 year, or 3 years after treatment). The outcomes of posterior circulation aneurysms were significantly better in the coil group than in the clip group after the 1st year of follow-up, and this difference persisted after 3 years of follow-up. However, while aneurysms in the anterior circulation were well matched in their anatomical location between the 2 treatment arms, this was not the case in the posterior circulation where, for example, 18 of 21 posterior inferior cerebellar artery aneurysms were in the clip group.

CONCLUSIONS

Based on mRS scores at 3 years, the outcomes of all patients assigned to coil embolization showed a favorable 5.8% absolute difference compared with outcomes of those assigned to clip occlusion, although this difference did not reach statistical significance (p=0.25). Patients in the clip group had a significantly higher degree of aneurysm obliteration and a significantly lower rate of recurrence and retreatment. In post hoc analysis examining only anterior circulation aneurysms, no outcome difference between the 2 treatment cohorts was observed at any recorded time point. CLINICAL TRIAL REGISTRATION NO.: NCT01593267 ( ClinicalTrials.gov ).

Effect of core laboratory and multiple-reader interpretation of angiographic images on follow-up outcomes of coiled cerebral aneurysms: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Reported rates of recanalization following coil embolization vary widely across studies. Some confounders are known to affect outcomes but others remain questionable. In the current study, we assess differences in reported angiographic outcomes for cerebral aneurysms treated with coil embolization as a function of single vs multiple readers and site investigator vs core laboratory settings.

MATERIALS AND METHODS

Our systematic review covered 1999-2011 by using Ovid MEDLINE and EMBASE. Search terms were subarachnoid hemorrhage, intracranial aneurysms, endovascular treatment, and coiling. Inclusion criteria were >50 aneurysms and available imaging follow-up. Study characteristics of interest were readers at the treating site(s) or at an independent core imaging facility, single vs multiple readers, number of aneurysms treated, mean aneurysm size, mean follow-up time, coil type, initial rupture status, and angiographic follow-up. We defined "unfavorable angiographic outcome" as either "recanalization," <90% occlusion, or "incomplete occlusion."

RESULTS

There were 104 (2.6%) of 4022 studies that fulfilled our inclusion criteria, comprising a total of 22,134 treated aneurysms, of which 15,969 (72.1%) had reported angiographic follow-up. The overall unfavorable outcome rate was 17.8% (2955/15,969 aneurysms). Eight (7.7%) of 104 studies reported core laboratory readings in which the pooled rate of unfavorable outcomes was 0.23 (95% CI, 0.19-0.28) compared with 0.16 (95% CI, 0.14-0.18) in readings from the treating sites (P < .001). The multivariate meta-regression suggested that core laboratory interpretation was significant for unfavorable outcomes (OR, 5.60; 95% CI, 2.01-15.60; P = .001), after adjustment for initial rupture status, aneurysm size, follow-up duration, and coil type. No significant association was found with use of multiple readers.

CONCLUSIONS

Core laboratory studies tend to report higher rates of unfavorable outcomes compared with self-reported studies.

Endovascular treatment of ruptured intracranial aneurysms: factors affecting midterm quality anatomic results: analysis in a prospective, multicenter series of patients (CLARITY)

BACKGROUND AND PURPOSE

Recanalization is 1 drawback of the EVT of intracranial aneurysms. An analysis of the factors affecting the midterm anatomic results after EVT of ruptured intracranial aneurysms in a large multicenter series (CLARITY) is presented.

MATERIALS AND METHODS

Of the 782 patients initially included in the CLARITY trial, 649 would theoretically undergo midterm follow-up examinations. Finally, 517/649 (79.7%) completed a midterm follow-up examination. Midterm anatomic results were independently and anonymously evaluated by 2 experienced neuroradiologists.

RESULTS

In univariate analysis, factors affecting the quality of midterm occlusion were the quality of the postoperative occlusion (P < .001), hypertension (P = .018), aneurysm size (P = .007), neck size (P = .005), and ICA location (P = .049). In multivariate analysis, 3 factors were associated with the quality of postoperative aneurysm occlusion: neck size (P = .003), use of the balloon remodeling technique (P = .031), and the quality of postoperative occlusion (P < .001). In univariate analysis, the evolution of aneurysm occlusion was affected by age (P = .024) and neck size (P = .041). In multivariate analysis, it was associated with the same factors: age (P = .025) and neck size (P = .043).

CONCLUSIONS

Among the many factors considered in this analysis, aneurysm neck size was identified as the single most important one in the quality of aneurysm occlusion at midterm follow-up after EVT. The present results suggest developing and evaluating new strategies of treatment and technique, especially for wide-neck aneurysms, with a focus on reinforcement and neoendothelialization at the level of the neck as objectives.