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

Retreatment rate and strategies for recurrent and residual aneurysms after Woven EndoBridge (WEB) treatment: a comprehensive systematic review and meta-analysis

Woven Endo Bridge (WEB) is a flow diverter device used to treat wide-necked intracranial aneurysms. We conducted a systematic review and meta-analysis to determine the retreatment rate and strategies following aneurysmal recurrence after WEB treatment. A systematic literature search was conducted through four electronic databases. The Cochrane risk of bias tool for non-randomized trials (ROBINS-I) was used for risk of bias assessment. A meta-analysis and meta-regression were performed on relevant variables. A total of 29 studies with 2067 patients were included. Initially treated aneurysms had an adequate occlusion rate of 84.7% (20 studies, 980/1156, 95%CI: 79%-89%) at the last follow-up. The overall retreatment rate was 8.6% (24 studies, 251/2893, 95%CI: 6.5%-10.9%). Following retreatment, the immediate complete occlusion rate post retreatment and complete occlusion rate at last follow-up were 52% (six studies, 95%CI, 11%-91%) and 65% (six studies, 77/120, 95%CI: 56%-73%) respectively. Stent-assisted coiling achieved a 100% (95%CI: 57%-100%, P-value < 0.01) immediate adequate occlusion rate and 74% complete occlusion rate (95%CI: 16%-100%, P-value = 0.63) at last follow-up, which was higher than clipping, coiling, and flow diversion. On meta-regression, aneurysm height and neck width significantly associated with higher retreatment rate. The current meta-analysis showed a 9% retreatment rate after initial aneurysms treatment with WEB and overall adequate retreatment occlusion was high. Although stent-assisted coiling showed a higher adequate occlusion rate post-operatively, there was no significant difference between retreatment strategies in long-term radiological outcomes.

Y Stent-Assisted Coiling Technique for Bifurcation Aneurysms Using Double Neuroform® Stent: a Large Restrospective Series

BACKGROUND

Stent assisted coiling technique have shown to be an effective and safe endovascular strategy for wide neck bifurcation aneurysms in achieving greater packing, allowing the closure of the aneurysm and preserving the parent arteries, compared to simple coiling.

MATERIAL AND METHODS

We conducted a retrospective analysis of 79 patients with cerebral aneurysms treated using 'Y'-configuration double Neuroform® stent-assisted coiling at our center from July 2009 to July 2022.

RESULTS

Of the 79 patients, 76% (60/79) were incidental unruptured cerebral aneurysm and 24% were patients treated for aneurysm recanalization of a previous ruptured aneurysm (19/79). The most frequent locations were anterior communicating artery (AComA) 44.3% (35/79) and middle cerebral artery (MCA) 32.9% (26/79). We found a complete and almost complete aneurysm occlusion (Raymond-Roy occlusion classification (RROC) 1 and 2): in 100% (79/79) in the angiography after procedure, in 97.6% (42/43) at the first follow-up at 6-8 months and 100% (57/57) at the first 1-2 years of follow-up. No mortality related to treatment was detected. We registered 2.5% (2/79) major ipsilateral strokes, one due to acute in stent thrombosis (patient had a mRS: 0 in follow up at 90 days) and a spinal anterior artery occlusion (patient had a mRS: 3 in follow up at 90 days).

CONCLUSION

The 'Y' stent-assisted coiling technique with double Neuroform® is a safe and effective technique for the treatment of wide-neck bifurcation aneurysms, with high rates of complete occlusion, preserving the permeability of the afferent and efferent arteries and low rate of complications.

Characteristics of middle cerebral artery aneurysms treated endovascularly in a clip-favored institution

BACKGROUND

The emergence of flow disruptors has brought a dynamic transition in the selection of treatment for middle cerebral artery (MCA) aneurysms, and the number of MCA aneurysms clipped is acceleratingly decreasing. Still, retreatment after endovascular treatment is still a dilemma, which may necessitate surgical clipping. It is all the more important to elucidate characteristics of MCA aneurysms that make clipping unfavorable. Thus, the practical characteristics of MCA aneurysms treated endovascularly in a clip-favored institution before the usage of flow disruption devices were investigated.

METHODS

This is a retrospective, single-center observational study. The clinical and imaging characteristics of treated MCA aneurysms from January 2012 to May 2022 were analyzed.

RESULTS

A total of 83 aneurysms were included; 70 aneurysms (84%) were clipped, and 13 (16%) were treated endovascularly. Eighteen aneurysms (22%) were ruptured (clipping, 12; endovascular, 6). The reasons for an endovascular treatment were as follows: distal (3); subacutely ruptured with burdens of spasm (2); multiple aneurysms (6: another clipped in 3, coiled in 1, and conservatively managed in 2); no access to the operating room due to COVID-19 (1); and retreatment after coiling (1). Endovascular group aneurysms were smaller (maximum diameter 5.2 vs 7.3 mm, p < 0.01, as well as dome, neck, and height) without differences in the dome/neck and aspect (height/neck) ratios. In a subgroup analysis of 78 MCA bifurcation aneurysms, the endovascular group was still smaller (dome 4.4 vs 5.8 mm, p = 0.025; neck 2.8 vs 3.9, p = 0.03).

CONCLUSION

In a limited series from a clip-favored institution before the flow disruption era, factors guided to endovascular treatments on MCA aneurysms were rather anatomical and clinical factors such as distal location, subacutely ruptured, multiple, or retreatment after coiling, than morphological factors such as dome/neck and aspect ratios albeit smaller size.

Predictors of Aneurysm Obliteration in Patients Treated with the WEB Device: Results of a Multicenter Retrospective Study

BACKGROUND AND PURPOSE

Despite the numerous studies evaluating the occlusion rates of aneurysms following WEB embolization, there are limited studies identifying predictors of occlusion. Our purpose was to identify predictors of aneurysm occlusion and the need for retreatment.

MATERIALS AND METHODS

This is a review of a prospectively maintained database across 30 academic institutions. We included patients with previously untreated cerebral aneurysms embolized using the WEB who had available intraprocedural data and long-term follow-up.

RESULTS

We studied 763 patients with a mean age of 59.9 (SD, 11.7) years. Complete aneurysm occlusion was observed in 212/726 (29.2%) cases, and contrast stasis was observed in 485/537 (90.3%) of nonoccluded aneurysms. At the final follow-up, complete occlusion was achieved in 497/763 (65.1%) patients, and retreatment was required for 56/763 (7.3%) patients. On multivariable analysis, history of smoking, maximal aneurysm diameter, and the presence of an aneurysm wall branch were negative predictors of complete occlusion (OR, 0.5, 0.8, and 0.4, respectively). Maximal aneurysm diameter, the presence of an aneurysm wall branch, posterior circulation location, and male sex increase the chances of retreatment (OR, 1.2, 3.8, 3.0, and 2.3 respectively). Intraprocedural occlusion resulted in a 3-fold increase in the long-term occlusion rate and a 5-fold decrease in the retreatment rate (P < .001), offering a specificity of 87% and a positive predictive value of 85% for long-term occlusion.

CONCLUSIONS

Intraprocedural occlusion can be used to predict the chance of long-term aneurysm occlusion and the need for retreatment after embolization with a WEB device. Smoking, aneurysm size, and the presence of an aneurysm wall branch are associated with decreased chances of successful treatment.

Initial Experiences with the Trenza Embolization Device for the Treatment of Wide-Neck Intracranial Aneurysms: A 12-Patient Case Series

The Trenza embolization device is a frame coil implant with flow-disruption properties and is a new alternative to treat challenging mid-to-large-sized broad-neck bifurcation or sidewall aneurysms. We conducted an observational single-center retrospective study of 12 consecutive patients treated for 10 unruptured and 2 ruptured 6- to 12-mm broad-neck bifurcation or sidewall aneurysms with the Trenza device during 2022-2023. The median patient age was 64 years (interquartile range, 59-70 years), 58% were women, the median largest aneurysm diameter was 9.6 mm (interquartile range, 7.5-11.9 mm), the median dome-to-neck ratio was 1.8 (interquartile range, 1.6-1.9), the most common aneurysm locations were the anterior communicating artery (33%) and basilar artery tip (33%). After a median follow-up of 6.5 months, adequate aneurysm occlusion was achieved in 83%. There were 3 major ischemic complications (25%), leading to 2 permanent neurologic deficits (17%) and 1 transient neurologic deficit (8%). There was 1 fatal rupture of a treated aneurysm 1.6 months after the index treatment. Two patients were retreated (17%). Ischemic complications occurred in patients after a too-dense coil packing at the base of the aneurysm. No technical issues related to the device were encountered. In summary, an adequate aneurysm occlusion rate was achieved using the Trenza-assisted coiling technique for otherwise challenging mid-to-large-sized broad-neck aneurysms. Ischemic complications seemed to occur following overdense coiling at the base of the aneurysm.

Imaging follow-up strategy after endovascular treatment of Intracranial aneurysms: A literature review and guideline recommendations

OBJECTIVE

Endovascular coil embolization is the primary treatment modality for intracranial aneurysms. However, its long-term durability remains of concern, with a considerable proportion of cases requiring aneurysm reopening and retreatment. Therefore, establishing optimal follow-up imaging protocols is necessary to ensure a durable occlusion. This study aimed to develop guidelines for follow-up imaging strategies after endovascular treatment of intracranial aneurysms.

METHODS

A committee comprising members of the Korean Neuroendovascular Society and other relevant societies was formed. A literature review and analyses of the major published guidelines were conducted to gather evidence. A panel of 40 experts convened to achieve a consensus on the recommendations using the modified Delphi method.

RESULTS

The panel members reached the following consensus: 1. Schedule the initial follow-up imaging within 3-6 months of treatment. 2. Noninvasive imaging modalities, such as three-dimensional time-of-flight magnetic resonance angiography (MRA) or contrast-enhanced MRA, are alternatives to digital subtraction angiography (DSA) during the first follow-up. 3. Schedule mid-term follow-up imaging at 1, 2, 4, and 6 years after the initial treatment. 4. If noninvasive imaging reveals unstable changes in the treated aneurysms, DSA should be considered. 5. Consider late-term follow-up imaging every 3-5 years for lifelong monitoring of patients with unstable changes or at high risk of recurrence.

CONCLUSIONS

The guidelines aim to provide physicians with the information to make informed decisions and provide patients with high-quality care. However, owing to a lack of specific recommendations and scientific data, these guidelines are based on expert consensus and should be considered in conjunction with individual patient characteristics and circumstances.

Aneurysmal recurrence and retreatment modalities after Woven EndoBridge (WEB) device implantation: A systematic review and meta-analysis

BACKGROUND

The Woven EndoBridge (WEB) device is used to treat wide-neck bifurcation aneurysms (WNBAs). We conducted a systematic review and meta-analysis to determine the retreatment rate strategies following aneurysmal recurrence of WEB device treated WNBAs.

METHODS

This study is reported following the PRISMA 2020 guidelines. We conducted a systematic review of the literature using PubMed, Scopus, Embase, and Web of Science. Data were pooled using a random-effects model. We calculated pooled prevalence and corresponding 95% confidence intervals (CI).

RESULTS

We included 11 studies. The overall retreatment rate was 171/1875 aneurysms (10.3%; 95% CI  =  8.3-12.9). Stent-assisted coiling was used to treat 59 aneurysms (36.7%; 95% CI  =  26.4-48.5), and flow diverters were used to treat 44 aneurysms (18.7%; 95% CI  =  9.9-32.5). Following retreatment, the complete occlusion rate was 57/91 aneurysms (62.8%; 95% CI  =  48.2-75.3) and the adequate occlusion rate was 24/91 aneurysms (26.4%; 18.4%-36.4%). The most common aneurysmal recurrence site was the anterior communicating artery (44/136 aneurysms, 32.4%; 95% CI  =  25.0-40.7).

CONCLUSIONS

Roughly 10% of WNBAs initially treated with the WEB device will undergo retreatment. Retreatment is an effective strategy for WEB-treated aneurysms, with high rates of adequate and complete occlusion. Future studies should work to identify risk factors for aneurysmal recurrence.

WEB Treatment of Ruptured Intracranial Aneurysms: Long-Term Follow-up of a Single-Center Cohort of 100 Patients

BACKGROUND AND PURPOSE

The Woven EndoBridge device (WEB) was introduced for the intrasaccular treatment of wide-neck aneurysms without the need for adjunctive devices. We used the WEB as a primary treatment for 100 ruptured aneurysms regardless of neck size or location. In this study, we present the long-term follow-up of 78 surviving patients.

MATERIALS AND METHODS

Between February 2015 and April 2017, one hundred ruptured aneurysms were treated with the WEB. For surviving patients, angiographic and clinical follow-up was scheduled at 3 months, and 3T MRA and clinical follow-up, at 6, 12, 36, and 60 months. Of 100 patients, 18 died during hospital admission, and in 4, the ruptured aneurysm was additionally treated. The remaining 78 patients had a mean follow-up of 51 months (median, 52 months; range, 5-84 months). There were 57 women and 21 men, with a mean age of 58.5 years (median, 59 years; range, 24-80 years). Of 78 aneurysms with long-term follow-up, 52 (66%) had a wide neck.

RESULTS

Of 78 ruptured aneurysms, 56 (72%) remained completely occluded and 17 (22%) had a stable small neck remnant. Five of 78 aneurysms (6%; 95% CI, 2.4%-14.5%) reopened during follow-up and were additionally treated. There were no rebleeds during follow-up.

CONCLUSIONS

Treatment of ruptured aneurysms with the WEB was safe and effective and has long-term results comparable with those of simple coiling of small-neck aneurysms. The WEB proved to be a valuable alternative to coils for both wide- and small-neck ruptured aneurysms without the need for stents, balloons, or antiplatelet therapy.

Assessment of balloon remodeling techniques in endovascular treatment of wide-neck intracranial aneurysms (WN-IAs)

OBJECTIVES

To evaluate the clinical, technical, and angiographic results in endovascular management of wide-neck intracranial aneurysms (WN-IAs) using the balloon-remodeling technique.

METHODS

This study was a prospective, single-center study that was carried out over a period of three years from January 2019 to December 2021 at the Neuro-Interventional Unit at our hospital. Patients who presented with WNIAs and were eligible for endovascular treatment using the balloon-remodeling approach were included in the study.

RESULTS

We included 37 patients with a mean age of 49.7 ± 12.3 years. About 91.9% of the participants had SAH, 5.4% had unruptured aneurysms, and 2.7% had intracranial hemorrhage. The mean time to treatment was 6.97 ± 7.35 days, the mean aneurysm diameter was 5.7 ± 1.7 mm, and the mean neck diameter was 3.8 ± 1.0 mm. The majority of the patients had a dom-to-neck ratio of less than 2 (89.2%). We have used hyper form balloons in 48.6%, hyper glide in 43.2%, Copernic balloons in 5.4%, and eclipse in 2.7%. According to the Raymond-Roy occlusion classification, 86.5% of the patients had complete obliteration, 10.8% had residual neck, and 2.7% had a residual aneurysm. Almost 91.9% had no complications, 2.7% had ischemia, and 5.4% had mild rupture by wire, treated by 5 min hyperinflation of the balloon till hemorrhage stopped.

CONCLUSIONS

Balloon-assisted detachable coiling is an important option in the treatment of WN-IAs. We found that this technique allowed safe and efficient treatment of aneurysms when conventional treatment had failed due to WN. Endovascular coiling using the balloon remodeling technique of wide neck showed a high technical success rate and good short-term clinical outcomes. A good selection of patients with WN-IAs treated by endovascular coiling using balloon remodeling technique and a good selection of materials used help in decreasing the complications.

Intracranial wide neck aneurysms: clinical and angiographic outcomes of endovascular management

Background

The treatment of intracranial wide neck aneurysms (WNAs) is usually difficult, hence several endovascular techniques were developed. This study aims to assess the clinical and angiographic imaging outcome of endovascular management of intracranial wide neck aneurysm. Forty patients were referred to the neuro-endovascular unit, at our hospital, each with a wide neck aneurysm. They were assessed regarding clinical presentation, aneurysm size, the character of the aneurysm, and the age and sex of the patient. Post-procedural, clinical, and angiographic outcomes of the patients who underwent endovascular intervention were reviewed.

Results

In this study, the mean aneurysmal neck was 5.4 ± 1.6 mm (mm). Endovascular intervention was carried out in all 40 patients in the form of simple coiling in 3 patients, double-catheter technique in 5 patients, balloon-assisted coiling (BAC) in 16 patients, stent-assisted coiling (SAC) in 13 patients, and flow diverter (FD) in 3 patients. Regarding clinical outcome, 4 patients had unfavorable outcome (the modified Rankin Scale, mRS > 2) at presentation and 3 patients at discharge. There was no unfavorable clinical outcome at 6- and 12-month follow-ups. Overall angiographic outcome at 1-year follow-up, 37/40 aneurysms (92.5%) had complete occlusion while two aneurysms had neck recurrence and one aneurysm had neck recanalization.

Conclusion

The current endovascular techniques in the treatment of WNAs are considered effective, feasible, and safe.

Repeated Aneurysm Intervention

Over the past 25 years the endovascular treatment of cerebral aneurysms has gained preference in some countries over the traditional surgical procedures. The review part of the article clearly demonstrates that the clinical results of both modalities are similar and the difference is seen only in technical effectivity. Surgical techniques fail far less frequently than the endovascular ones. Incompletely occluded or growing aneurysms after the endovascular approach expose the patient to the risk of rebleeding with all possible consequences. Markedly repeated procedures are much more common for endovascularly treated aneurysms, again with all the risks.In the authors institution over the past 20 years, a total of 2032 aneurysms were treated. In 1263 endovascularly managed aneurysms the regrowth or inclomplete initial occlusion necessitated 159 repeated propcedures (12.6%). In surgical group the total of 27 aneurysms needed retreatment (3.5%). The difference is statistically significant. In nine patients in endovascular group the rebleeding was the reason for repeated procedures. No rebleeding was seen in the surgical group.This fact, also shown in the review part of the article, is important in patients counseling. Given the similar clinical results of both modalities the patient should be advised on the necessity of repeated follow-ups and of possible technical failure and eventual repeated procedure which is more likely if endovascular procedure is chosen.

Patient and aneurysm factors associated with aneurysm recanalization after coiling

BACKGROUND

One limitation of the endovascular treatment of intracranial aneurysms is aneurysm recanalization. The Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) study is a prospective multicenter cohort study evaluating the factors associated with recanalization after endovascular treatment.

METHODS

The current analysis is focused on patients treated by coiling or balloon-assisted coiling (BAC). Postoperative, mid-term vascular imaging, and evolution of aneurysm occlusion were independently evaluated by two neuroradiologists. A 3-grade scale was used for aneurysm occlusion (complete occlusion, neck remnant, and aneurysm remnant) and for occlusion evolution (improved, stable, and worsened). Recanalization was defined as any worsening of aneurysm occlusion.

RESULTS

Between December 2013 and May 2015, 16 French neurointerventional departments enrolled 1289 patients. A total of 945 aneurysms in 908 patients were treated with coiling or BAC. The overall rate of aneurysm recanalization at mid-term follow-up was 29.5% (95% CI 26.6% to 32.4%): 28.9% and 30.3% in the coiling and BAC groups, respectively. In multivariate analyses factors independently associated with recanalization were current smoking (36.6% in current smokers vs 24.5% in current non-smokers (OR 1.8 (95% CI 1.3 to 2.4); p=0.0001), ruptured status (31.9% in ruptured aneurysms vs 25.1% in unruptured (OR 1.5 (95% CI 1.1 to 2.1); p=0.006), aneurysm size ≥10 mm (48.8% vs 26.5% in aneurysms <10 mm (OR 2.6 (95% CI 1.8 to 3.9); p<0.0001), wide neck (32.1% vs 25.8% in narrow neck (OR 1.5 (95% CI 1.1 to 2.1); p=0.02), and MCA location (34.3% vs 28.3% in other locations (OR 1.5 (95% CI 1.0 to 2.1); p=0.04).

CONCLUSIONS

Several factors are identified by the ARETA study as playing a role in aneurysm recanalization after coiling: current smoking, aneurysm status (ruptured), aneurysm size (≥10 mm), neck size (wide neck), and aneurysm location (middle cerebral artery). This finding has important consequences in clinical practice.

TRIAL REGISTRATION NUMBER

URL: http://www.clinicaltrials.gov; Unique Identifier: NCT01942512.

Development and assessment of machine learning models for predicting recurrence risk after endovascular treatment in patients with intracranial aneurysms

Intracranial aneurysms (IAs) remain a major public health concern and endovascular treatment (EVT) has become a major tool for managing IAs. However, the recurrence rate of IAs after EVT is relatively high, which may lead to the risk for aneurysm re-rupture and re-bleed. Thus, we aimed to develop and assess prediction models based on machine learning (ML) algorithms to predict recurrence risk among patients with IAs after EVT in 6 months. Patient population included patients with IAs after EVT between January 2016 and August 2019 in Hunan Provincial People's Hospital, and an adaptive synthetic (ADASYN) sampling approach was applied for the entire imbalanced dataset. We developed five ML models and assessed the models. In addition, we used SHapley Additive exPlanations (SHAP) and local interpretable model-agnostic explanation (LIME) algorithms to determine the importance of the selected features and interpret the ML models. A total of 425 IAs were enrolled into this study, and 66 (15.5%) of which recurred in 6 months. Among the five ML models, gradient boosting decision tree (GBDT) model performed best. The area under curve (AUC) of the GBDT model on the testing set was 0.842 (sensitivity: 81.2%; specificity: 70.4%). Our study firstly demonstrated that ML-based models can serve as a reliable tool for predicting recurrence risk in patients with IAs after EVT in 6 months, and the GBDT model showed the optimal prediction performance.

Endovascular treatment of residual or recurrent intracranial aneurysms after surgical clipping

OBJECTIVE

Total aneurysm occlusion is crucial for the prevention of rebleeding of a ruptured aneurysm or to avoid rupture of an unruptured lesion. Both surgical and endovascular embolization fail to achieve complete aneurysm occlusion in all the cases. The objective of the study was to establish the safety and efficacy of endovascular treatment for previously clipped residual or recurrent aneurysms.

METHODS

This was an observational, retrospective study of patients harboring incompletely occluded intracranial aneurysms after clipping who underwent endovascular treatment. Patients were treated using 4 different techniques: (1) simple coiling, (2) balloon remodeling, (3) stent-assisted coiling, and (4) flow diversion. Analyses were performed to identify predictors of total aneurysm occlusion, recanalization and complications.

RESULTS

Between May 2010 and September 2018, 70 patients harboring incompletely occluded intracranial aneurysms after clipping met the inclusion criteria in 5 centers. The mean residual aneurysm size was 7.5 mm. Fifty-nine aneurysms were unruptured. Total aneurysm occlusion was achieved in 75.3% of the aneurysms after 1 year. All aneurysms treated with flow diversion revealed complete occlusion according to control angiography. Recanalization was observed in 14.5%. Permanent morbidity and mortality occurred in 2.9% and 1.4% of the patients, respectively.

CONCLUSIONS

Endovascular treatment of recurrent or residual aneurysms after surgical clipping was safe and efficacious. Flow diversion seems to be associated with better anatomical results. A more rigid study, a larger group of patients, and longterm follow-up are required to provide stronger conclusions about the best approach for residual clipped aneurysms.

Endovascular Management of Distal Anterior Cerebral Artery Aneurysms: A Multicenter Retrospective Review

INTRODUCTION

Distal anterior cerebral artery aneurysms (DACAA) are a rare and difficult entity to manage. Endovascular treatment has evolved for safe and durable treatment of these lesions. The objective of this study is to report the safety, efficacy, and outcomes of endovascular treatment of DACAA.

METHODS

A retrospective review of DACAA endovascularly treated at 5 different institutions was performed. Data included demographics, rupture status, radiographic features, endovascular technique, complication rates, and long-term angiographic and clinical outcomes. A primary endpoint was a good clinical outcome (modified Rankin scale 0-2). Secondary endpoints included complications and radiographic occlusion at follow-up.

RESULTS

A total of 84 patients were reviewed. The mean age was 56, and 64 (71.4%) were female. Fifty-two (61.9%) aneurysms were ruptured. A good functional outcome was achieved in 59 patients (85.5%). Sixty (71.4%) aneurysms were treated with primary coiling, and the remaining 24 were treated with flow diversion. Adequate occlusion was achieved in 41 (95.3%) aneurysms treated with coiling, and 17 (89.5%) with flow diversion. There were total 11 (13%) complications. In the flow diversion category, there were 2, both related to femoral access. In the coiling category, there were 9: 5 thromboembolic, 3 ruptures, and 1 related to femoral access.

CONCLUSION

Endovascular treatment, and in particular, flow diversion for DACAA, is safe, feasible, and associated with good long-term angiographic and clinical outcomes.

WEB device for treatment of posterior communicating artery aneurysms

BACKGROUND

Woven EndoBridge (WEB) device treatment of wide-neck bifurcation aneurysms has proved to be safe and effective, but the use of these devices in sidewall aneurysms has been reported only in a small number of case series.

OBJECTIVE

To report our results in a cohort of consecutive patients in whom a WEB device was used as first-line treatment for posterior communicating artery (PComA) aneurysms.

METHODS

We conducted a retrospective analysis of a prospectively maintained database of PComA aneurysms treated with a WEB device in our institution from June 1, 2012 to November 15, 2020. Clinical and radiological findings were evaluated at immediate and last follow-up.

RESULTS

A total of 219 aneurysms were treated with a WEB device, including 15 PComA aneurysms in 15 patients, 10 of which were ruptured. Aneurysms were wide necked, with a mean aspect ratio of 1.6 (range 0.7-3.0) and a mean neck size of 4.2 mm (range 2.6-7.4 mm). No intraoperative rupture occurred and only one thromboembolic event was noted. Among the group with at least a 3-month digital subtraction angiography (DSA) follow-up, complete and adequate occlusion were obtained in 54% and 72%, respectively (average follow-up 13 months). Re-treatment was needed for two initially ruptured aneurysms. No procedure-related morbidity or mortality was reported.

CONCLUSION

This series suggests the high safety profile of WEB devices even when used in off-label indications. Treatment with these devices seems to be a valuable strategy for ruptured wide-neck PComA aneurysms, avoiding the need for antiplatelet medication. However, occlusion rates should be investigated in further larger studies.

Short- and midterm outcome of ruptured and unruptured intracerebral wide-necked aneurysms with microsurgical treatment

To clip or coil has been matter of debates for several years and is the domain of interdisciplinary decision making. However, the microsurgical outcome has still been elusive concerning wide neck aneurysms (WNA). A retrospective single center study was performed with all patients with ruptured WNA (rWNA) and unruptured WNA (uWNA) admitted to author´s institute between 2007–2017. Microsurgical outcome was evaluated according to Raymond-Roy occlusion grade and follow-up angiography was performed to analyze the stability of neck/aneurysm remnants and retreatment poverty. Of 805 aneurysms, 139 were rWNA (17.3%) and 148 uWNA (18.4%). Complete occlusion was achieved in 102 of 139 rWNA (73.4%) and 112 of 148 uWNA (75.6%). Neck remnants were observed in 36 patients with rWNA (25.9%) and 30 patients with uWNA (20.3%), 1 (0.7%) and 6 (4.1%) patients had aneurysmal remnant, respectively. Overall complication rate was 11.5%. At follow-up (939/1504 months), all remnants were stable except for one, which was further conservatively treated with marginal retreatment rate under 1%. Even the risk of de-novo aneurysm was higher than the risk for remnant growth (2.6% vs 0% in rWNA; 8.7% vs 5.3% in uWNA) without significant difference. Microsurgical clipping is effective for complete occlusion of r/uWNA with low complication. Furthermore, the risk of remnant growth is marginal even lower than the risk of de-novo rate low retreatment rate.

The Woven EndoBridge (WEB) Versus Conventional Coiling for Treatment of Patients with Aneurysmal Subarachnoid Hemorrhage: Propensity Score-Matched Analysis of Clinical and Angiographic Outcome Data

OBJECTIVE

Conventional coiling is standard for treatment of ruptured intracranial aneurysms. We compared clinical and angiographic outcomes between intrasaccular flow disruption with the Woven EndoBridge (WEB) and conventional coiling in patients with aneurysmal subarachnoid hemorrhage (aSAH) using a propensity score-matched analysis.

METHODS

This is a retrospective study of consecutive patients with aSAH treated with the WEB or conventional coiling between 2010 and 2019. Baseline characteristics, procedural complications, angiographic results, and functional outcome were compared between both groups.

RESULTS

Fifty-two patients treated with the WEB and 236 patients treated by coiling were included. The WEB group was characterized by a higher patient age (P = 0.024), a wider aneurysm neck (P < 0.001), and more frequent location at the posterior circulation (P = 0.004). Procedural complications were comparable between WEB (19.2%) and coiling (22.7%, P = 0.447). In-hospital mortality rates were higher in the coiling group (WEB: 5.8%, coiling: 17.8%; P = 0.0034). Favorable outcome (modified Rankin scale ≤2) was obtained in 51.3% after WEB embolization and in 55.0% after coiling (P = 0.653). Retreatment was performed in 26.4% of patients after WEB and in 25.8% after coiling (P = 0.935). Propensity score analysis confirmed these results and revealed higher adequate occlusion rates at midterm follow-up for WEB-treated aneurysms (WEB: 93.9%, coiling: 76.2%, P = 0.058).

CONCLUSIONS

Compared with conventional coiling, aSAH patients treated with the WEB have a similar clinical and potentially improved angiographic outcome at midterm follow-up. The WEB might be considered as an alternative to conventional coiling for the treatment of RIAs, in particular for those with wide-necked and thus challenging anatomy.

The safety and outcomes of acutely ruptured intracranial aneurysms with incomplete occlusion after coiling: a case-control study

BACKGROUND

Incomplete aneurysmal occlusion is a common feature of immediate posttreatment angiography. The safety and outcomes of acutely ruptured intracranial aneurysms (RIAs) with incomplete occlusion after stent-assisted coiling (SAC) and no-stent coiling (NSC) have not been well clarified. Progressive occlusion of stents can promote the complete occlusion of intracranial aneurysms (IAs), but it remains to be determined if progressive occlusion in acutely RIAs with incomplete occlusion after coiling may be enhanced by protective stenting. This study aimed to evaluate the safety and outcomes of those aneurysms after SAC and NSC; And to discover whether the stents can promote progressive aneurysm occlusion in such lesions or not.

METHODS

We reviewed 199 patients with acutely RIAs underwent endovascular coiling and developed incomplete occlusion in the past seven years. The patients' clinical and imaging information were recorded and analyzed. Univariate and multivariate analyses were performed to determine the association of recurrence rate with potential risk factors.

RESULTS

SAC group had wider aneurysms neck (3.471 mm vs 2.830 mm, P = 0.009) and smaller dome-to-neck ratio (1.536 vs 2.111, P = 0.001) than in NSC group. There was no significant difference between the two groups in total procedure-related complications rate (31.7% vs 23.5%, P = 0.195), procedure-related mortality (6.9% vs 2.0%, P = 0.170) and modified Rankin Scale (mRS) score at 6-month follow-up (P > 0.05). However, SAC group had significantly higher ischemic complications rate (21.8% vs 8.2%, P = 0.007) and complete occlusion rate (65.6% vs 48.3%, P = 0.020), and lower recurrence rate (15.6% vs 28.1%, P = 0.042) than NSC group based on 6-month follow-up angiograms. Additionally, Multivariable analysis showed NSC was an independent risk factor for aneurysm recurrence (Odds Ratio [OR]: 4.061; P = 0.018).

CONCLUSIONS

Acutely RIAs with incomplete occlusion after SAC is associated with higher complications rate and mortality, but has an acceptable safety profile and similar clinical outcome compared to NSC, as well as gives patients superior angiography outcome by progressive occlusion of stents.

Safety and efficacy of anterior communicating artery compromise during endovascular coil embolization of adjoining aneurysms

OBJECTIVE

In the presence of symmetric A1 flow, the safety and efficacy of compromising the anterior communicating artery (ACoA) during coil embolization of ACoA aneurysms has yet to be evaluated. Herein, the authors describe their experience, focusing on procedural safety.

METHODS

Between October 2012 and July 2017, 285 ACoA aneurysms with symmetric A1 flows were treated at the authors' institution by endovascular coil embolization. Clinical and angiographic outcome data were subjected to binary logistic regression analysis.

RESULTS

ACoA compromise was chosen in the treatment of 71 aneurysms (24.9%), which were completely (n = 15) or incompletely (n = 56) compromised. In the remaining 214 lesions, the ACoA was preserved. Although 9 patients (3.2%) experienced procedure-related thromboembolisms (compromised, 4; preserved, 5), all but 1 patient (with ACoA compromise) were asymptomatic. In multivariate analysis, subarachnoid hemorrhage at presentation was the sole independent risk factor for thromboembolism (OR 15.98, p < 0.01), with ACoA compromise being statistically unrelated. In 276 aneurysms (96.8%) with follow-up of > 6 months (mean 20.9 ± 13.1 months, range 6-54 months), recanalization was confirmed in 21 (minor, 15; major, 6). A narrow (≤ 4 mm) saccular neck (p < 0.01) and ACoA compromise (p = 0.04) were independently linked to prevention of recanalization.

CONCLUSIONS

During coil embolization of ACoA aneurysms, the ACoA may be compromised without serious complications if A1 flows are symmetric. This approach may also confer some long-term protection from recanalization, serving as a valid treatment option for such lesions.

Evaluation of clinical and anatomical outcome of staged stenting after acute coiling of ruptured intracranial aneurysms

INTRODUCTION

Stent-assisted coiling has widened indications and improved stability of endovascular treatment of intracranial aneurysms. However, stent-assisted coiling is usually not used to treat acutely ruptured intracranial aneurysms to avoid antiplatelet therapy. The objective of this study is to evaluate a strategy of staged endovascular treatment of ruptured intracranial aneurysms including coiling at the acute phase with complementary stenting with or without coiling at the subacute phase.

MATERIAL AND METHODS

Between 2012 and 2017, we retrospectively identified, in our prospectively maintained database, all patients treated for a ruptured intracranial aneurysm based on this staged stenting strategy. Clinical charts and imaging follow-up were analyzed to assess the procedural safety and feasibility as well as clinical and anatomical outcome.

RESULTS

We identified 23 patients with 23 intracranial aneurysms including 15 (65.2%) women with a mean age of 50 years (range 24-69 years). No rebleeding occurred during the mean delay of 24.3 days between initial coiling and stenting. All procedures were successful and additional coiling was performed in 5/23 procedures (21.7%). Clinical status was unchanged in all patients. At follow-up, the modified Rankin scale was graded 0 in 19/23 (82.6%), 1 in 2/23 (8.7%), and 2 in 2/23 (8.7%) patients, respectively. The rate of complete occlusion rose from 30.4% before the stenting procedure to 52.2% immediately after and 72.7% at follow-up.

CONCLUSION

This strategy of early staged stenting in selected patients is safe and improves immediate intracranial aneurysm occlusion and long-term stability in this population at high risk of intracranial aneurysm recurrence with coiling alone.

[The role of interventional neuroradiology in treatment of hemorrhagic stroke]

Treatment of hemorrhagic strokes necessitates hospitalization in an accommodated hospital offering the possibility of a multidisciplinary approach. In this setting, over recent years interventional radiology has become increasingly important from the diagnostic as well as the therapeutic standpoint. In the context of subarachnoid hemorrhage by intracranial aneurysm rupture, the NICE (National Institute for Health and Clinical Excellence) and ASA (American Stroke Academy) recommendations suggest that endovascular coiling should be considered as an alternative to surgical clipping (class I, level of evidence B). As stenting is associated with increased morbidity and mortality in the ruptured aneurysms, it should be avoided (class III, level of evidence C). The patient's clinical status on presentation should be taken into account when deciding on therapeutic management and determining prognosis. Long-term clinical outcome depends on several factors: clinical status on arrival, comorbidities, age, occurrence of operative complications and complications of subarachnoid hemorrhage such as hydrocephaly, vasospasm and delayed cerebral ischemia, as well as complications stemming from prolonged bed rest. In the event of vasospasm refractory to maximal medical therapy, endovascular treatment by intra-arterial injection of Nimodipine and angioplasty can be envisioned. In the event of intracerebral hemorrhage (ICH) by rupture cerebral dural arteriovenous fistula, once the diagnosis has been confirmed, and given the exceedingly high risk of rebleeding, first-line treatment will consist in emergency endovascular embolization. In the event of intracerebral hemorrhage (ICH) by arteriovenous rupture, treatment is decided on during a multidisciplinary meeting and either carried out immediately or delayed according to several factors: clinical conditions, age of the patient, angioarchitecture and ICH location.

[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.

Endosurgical Remodeling of Wide-Necked Bifurcation Aneurysms

Background: Wide-necked cerebral aneurysms at a bifurcation can be difficult to treat with endovascular techniques despite recent advancements.

Objective: We describe a new technique of micro-scaffold remodeling of the aneurysm neck of wide-necked bifurcation aneurysms by placing one or more microcatheters and/or wires in the efferent vessels. We hypothesize that this technique would be a better choice to change the branch angulation, allowing for an improved configuration to stably deploy coils. We present a retrospective case series to illustrate this technique.

Methods: 17 wide-necked bifurcation aneurysms in 17 patients were coil embolized using this technique during a 3 year study period. Branch-vessel microcatheters and/or microwires were used to remodel the aneurysm neck and support the coil mass. Statistical analysis of the branch angulation and neck-width changes were performed during treatment. Long-term clinical outcome and follow-up angiography was obtained in 8 patients.

Results: Eleven patients had complete occlusion of their aneurysm (Raymond-Roy Class I), and 6 patients had Raymond-Roy Class 2 immediately after treatment. Efferent vessels demonstrated a statistically significant change in angulation with insertion of microcatheters or microwires, while neck width did not change significantly. There were four intraoperative complications and no neurological morbidity in the immediate post-operative period. Complete occlusion was documented for all 10 subjects with long-term follow-up.

Conclusions: The micro-scaffold endosurgical remodeling technique is a useful adjunct in treating wide-necked bifurcation aneurysms. By elevating branch vessels away from the aneurysm neck, this technique allows for dense coil packing while decreasing the need for balloon or stent assistance.

Stent assisted coiling versus non-stent assisted coiling for the management of ruptured intracranial aneurysms: a meta-analysis and systematic review

PURPOSE

To compare the safety and efficiency of stent assisted coiling (SAC) with non-SAC for the management of ruptured intracranial aneurysms.

METHODS

A meta-analysis that compared SAC with coiling alone and balloon assisted coiling was conducted by database searching. The primary outcomes of this study were immediate occlusion and progressive thrombosis rate, overall perioperative complication rate, and angiographic recurrence. Secondary outcomes included mortality at discharge, hemorrhagic and ischemic complications, and favorable clinical outcome at discharge and at follow-up.

RESULTS

Eight retrospective cohort studies with 1408 ruptured intracranial aneurysms (SAC=499; non-SAC=909) were included. The SAC group tended to show a lower immediate complete occlusion rate than the non-SAC group (54.3% vs 64.2%; RR 0.90; 95% CI 0.83 to 0.99; I²=17.4%) and achieved a significantly higher progressive complete rate at follow-up (73.4% vs 61.0%; RR 1.30; 95% CI 1.16 to 1.46; I²=40.5%) and a lower recurrence rate (4.8% vs 16.6%; RR 0.28; 95% CI 0.16 to 0.50; I²=0.0%). With respect to safety concerns, overall perioperative complications in the SAC group were significantly higher (20.2% vs 13.1%; RR 1.70; 95% CI 1.36 to 2.11; I²=0.0%). However, no significant difference was found for mortality rate at discharge (6.3% vs 6.2%; RR 1.29; 95% CI 0.86 to 1.94; I²=0.0%), or favorable clinical outcome rate at discharge (73.4% vs 74.2%; RR 0.95; 95% CI 0.88 to 1.02; I²=12.1%) and at follow-up (85.6% vs 87.9%; RR 0.98; 95% CI 0.93 to 1.02; I²=0.0%; P=0.338).

CONCLUSIONS

SAC has a lower recurrence rate than non-SAC. Nevertheless, further validation by well designed prospective studies is warranted for determining whether stents improve angiographic outcome without an increased complication rate or unfavorable clinical outcome.

Analysis of Wide-Neck Aneurysms in the Barrow Ruptured Aneurysm Trial

BACKGROUND

Ruptured wide-neck aneurysms (WNAs) are difficult to treat and few publications have compared clipping to coiling.

OBJECTIVE

To determine, using Barrow Ruptured Aneurysm Trial (BRAT) data: (1) How many aneurysms had a wide neck? (2) Did wide-neck status influence treatment? (3) How did clipping compare to coiling for WNAs?

METHODS

A post hoc analysis was conducted of saccular WNAs in the BRAT. A WNA was defined as maximum neck width ≥ 4 mm or maximum aneurysm dome-diameter–to–neck-width ratio < 2. Both intent-to-treat and as-treated analyses were performed.

RESULTS

Of the 327 patients analyzed, 177 (54.1%) had a WNA. WNAs were more likely to occur in older patients (P = .03) with worse presenting clinical grade (P = .02), were more likely to arise from the middle cerebral artery, basilar tip, or internal carotid artery other than the junction with the posterior communicating artery (P = .001) and were associated with worse clinical outcomes at all time points (P ≤ .01). WNAs were equally distributed in assigned treatment groups (clip 56.6% vs coil 51.8%; P = .38), but were overrepresented in the actual clipping group (clip 62.4% vs coil 37.6%, P < .001). Most patients (76.7%) in the coil-to-clip crossover group had a WNA. Comparing clipping to coiling, there was no difference in clinical outcomes at any time point in either analysis (P ≥ .33). The aneurysm obliteration rate was lower (P < .001) and the retreatment rate higher (P < .001) in the actual coiling group.

CONCLUSION

Wide-neck status significantly impacted treatment strategy in the BRAT, favoring clipping. Clipping and coiling of ruptured WNAs resulted in statistically similar long-term clinical outcomes.

10.1093/neuros/nyy439 Video Abstract 10.1093.neuros.nyy439 5850292551001

Selective compromise of hypoplastic posterior communicating artery variants with aneurysms treatable by coil embolization: clinical and radiologic outcomes

Background

Posterior communicating artery (PcoA) compromise may serve as adjunctive treatment in patients with hypoplastic variants of PcoA who undergo coil embolization of PcoA aneurysms. However, procedural safety and the propensity for later recanalization are still unclear.

Objective

To evaluate clinical and radiologic outcomes of coil embolization in this setting, focusing on compromise of PcoA.

Methods

As a retrospective review, we examined 250 patients harboring 291 aneurysms of hypoplastic PcoAs, all consecutively treated by coil embolization between January 2004 and June 2016. PcoA compromise was undertaken in conjunction with 81 of the treated aneurysms (27.8%; incomplete 53; complete 28). Medical records and radiologic data were assessed during extended monitoring.

Results

During the mean follow-up of 33.9±24.6 months (median 36 months), a total of 107 (36.8%) coiled aneurysms showed recanalization (minor 50; major 57). Recanalization rates were as follows: PcoA preservation 40.5% (85/210); incomplete PcoA occlusion 34.0% (18/53); complete PcoA occlusion 14.3% (4/28). Aneurysms >7 mm (HR 3.40; P<0.01), retreatment for recanalization (HR 3.23; P<0.01), and compromise of PcoA (P<0.01) emerged from multivariate analysis as significant risk factors for recanalization. Compared with PcoA preservation, complete PcoA compromise conferred more favorable outcomes (HR 0.160), whereas incomplete compromise of PcoA fell short of statistical significance. Thromboembolic infarction related to PcoA compromise did not occur in any patient.

Conclusion

PcoA compromise in conjunction with coil embolization of PcoA aneurysms appears safe in hypoplastic variants of PcoA, helping to prevent recanalization if complete occlusion is achieved.

Safety and efficacy of aneurysm treatment with WEB in the cumulative population of three prospective, multicenter series

BACKGROUND

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

PURPOSE

To report clinical and anatomical results of the WEB treatment in the cumulative population of three Good Clinical Practice (GCP) studies: WEBCAST (WEB Clinical Assessment of Intrasaccular Aneurysm), French Observatory, and WEBCAST-2.

METHODS

WEBCAST, French Observatory, and WEBCAST-2 are single-arm, prospective, multicenter, GCP studies dedicated to the evaluation of WEB treatment. Clinical data were independently evaluated. Postoperative and 1-year aneurysm occlusion was independently evaluated using the 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.

RESULTS

The cumulative population comprised 168 patients with 169 aneurysms, including 112 female subjects (66.7%). The patients' ages ranged between 27 and 77 years (mean 55.5±10.2 years). Aneurysm locations were middle cerebral artery in 86/169 aneurysms (50.9%), anterior communicating artery in 36/169 (21.3%), basilar artery in 30/169 (17.8%), and internal carotid artery terminus in 17/169 (10.1%). The aneurysm was ruptured in 14/169 (8.3%). There was no mortality at 1 month and procedure/device-related morbidity was 1.2% (2/168). At 1 year, complete aneurysm occlusion was observed in 81/153 aneurysms (52.9%), neck remnant in 40/153 aneurysms (26.1%), and aneurysm remnant in 32/153 aneurysms (20.9%). Re-treatment was carried out in 6.9%.

CONCLUSIONS

This series is at the moment the largest prospective, multicenter, GCP series of patients with aneurysms treated with WEB. It shows the high safety and good mid-term efficacy of this treatment.

CLINICAL TRIAL REGISTRATION

French Observatory: Unique identifier (NCT18069); WEBCAST and WEBCAST-2: Unique identifier (NCT01778322).

Impact of the global outflow angle on recanalization after endovascular treatment of middle cerebral artery bifurcation aneurysms

Background and purpose

Intracranial aneurysm recanalization after endovascular treatment (EVT) remains a major problem. The goal of this study was to find new predictive factors of recanalization after EVT of middle cerebral artery (MCA) bifurcation aneurysms.

Methods

96 MCA bifurcationaneurysms, ruptured or unruptured, treated by EVT between Septembre 2009 and December 2014, were retrospectively included. Clinical parameters and aneurysm characteristics were recorded. From the initial three-dimensional DSA, spatial coordinates found on parent and daughter arteries of MCA bifurcations gave four different flow angle values; inflow, outflows 1 and 2, and the global outflow angle (the sum of the two outflow angles). Inter- and intra-observer reproducibilities of three-dimensional angle value measurements were performed.

Results

Recanalization occurred in 25 cases (26%) and retreatment was performed in 11 cases (11%). Only 1 patient (1%) had rebleeding. Univariate analysis established the following as predictive factors of recanalization: high blood pressure (P=0.014), aneurysm height (P<0.001), aneurysm width (P<0.001), neck size (P<0.001), postoperative occlusion class (P=0.040), percentage of packing volume (P<0.001), as well as the two outflow angles (P=0.006 and 0.045), and the global outflow angle (P<0.001). Multivariate analysis revealed two independent risk factors for recanalization: the global outflow angle (OR=1.05; 95% CI 1.02 to 1.08; P<0.002) and aneurysm width (OR=0.67; 95% CI 0.46 to 0.96; P=0.031). A global outflow angle threshold <192° was found to be a risk factor for recanalization (OR=13.75; 95% CI 4.46 to 42.44), with a sensitivity of 80% and specificity of 77%.

Conclusions

This study emphasizes that a new parameter, the global outflow angle, can be predictive of recanalization for MCA bifurcation aneurysms treated by EVT.

Silk flow-diverter stent for the treatment of complex intracranial aneurysms: A one-year follow-up multicenter study

Background Flow-diverter stents have been successfully used in the treatment of complex aneurysms with limited therapeutic alternatives. We report our experience using the Silk flow diverter (SFD; Balt Extrusion, Montmorency, France) for the treatment of complex aneurysms in four Argentine centers. Methods We conducted a retrospective review of 246 consecutive patients who were treated with the SFD at four Argentine centers between January 2009 and January 2017. The patient and aneurysm characteristics, as well as the details of the procedure, were analyzed. The angiographic and clinical findings were recorded during and immediately after the procedure and at 12-month follow-up. Results Angiography follow-up at 12 months was possible in 235 patients (95.5%) with 282 aneurysms. A total of 265 aneurysms (93.9%) presented with complete occlusion of the aneurysmal sac (class 1) and 17 aneurysms (6.1%) presented with partial occlusion (class 2). The 12-month clinical follow-up showed 11 patients with major events (seven, scale 2; five, scale 3; and two, scale 4). The morbidity and mortality rates were 4.2% (11/289) and 2.1% (5/289), respectively. Conclusions The treatment of aneurysms with the SFD was associated with a low rate of complications and a high percentage of aneurysmal occlusion. These findings suggest that SFD is an effective and safe alternative in the endovascular treatment of complex aneurysms.

Cerebral aneurysm neck diameter is an independent predictor of progressive occlusion after stent-assisted coiling

BACKGROUND

Some intracranial aneurysms treated by stent-assisted coiling (SAC) with incomplete occlusion undergo progressive occlusion (PO) during follow-up period. We analyzed the predictors for the occurrence of PO.

METHODS

Among 74 cerebral aneurysms treated by SAC using the Enterprise or Neuroform stents from 2010 to 2015, we included 43 aneurysms with occlusion grade of neck remnant (NR, n = 36) or residual aneurysm (RA, n = 7) at the post-procedure. We defined PO as improvement in occlusion grade from RA to NR, or from NR or RA to complete occlusion on angiographic follow-up imaging at 6 months after the procedure. We analyzed the independent predictors for PO using a multivariate logistic regression model and receiver operating characteristic (ROC) curve analysis.

RESULTS

Forty-three aneurysms were analyzed, with mean volume embolization ratio of 30.3 ± 6.7%. Twenty aneurysms (47%) achieved PO. Univariate analysis found that the median neck diameter of the aneurysms was smaller in aneurysms with PO than others. Multivariate logistic regression analysis also found that the odds ratio of neck diameter of the aneurysm for PO was 0.44 (95% CI, 0.19-0.82, p < 0.01). Moreover, ROC curve analysis for PO found that the optimal cut-off value of the neck diameter was 5.5 mm, with a sensitivity of 95%, specificity of 57% (p < 0.01).

CONCLUSIONS

Incompletely occluded aneurysms with a neck diameter of 5.5 mm or less might be more likely to develop PO within 6 months after SAC by using Enterprise or Neuroform stents.

Leo stent for endovascular treatment of intracranial aneurysms: very long-term results in 50 patients with 52 aneurysms and literature review

INTRODUCTION

The Leo stent was the first retrievable stent for endovascular treatment of intracranial aneurysms (IAs). We report our experience with this device with emphasis on very long-term follow-up.

METHODS

This study was approved by authors' ethical committee. A retrospective review of our prospectively maintained database identified all patients treated for a saccular IA with this stent in our institution. Technical issues and immediate and long-term outcomes (at least 12 months) were evaluated.

RESULTS

Between 2004 and 2015, 50 patients with 52 IAs were identified. In two patients, the stent could not safely be placed (failure rate = 3.8%). Among 48 treated patients with 50 IAs, there were 44 women and 4 men (mean age, 53 years). Mean aneurysm diameter was 7.2 mm. All IAs but six were wide-necked. There was no immediate morbidity or mortality. Anatomical results included 76% complete occlusions, 22% neck remnants, and 2% incomplete occlusions. Mean follow-up was 50.2 months (range, 12-139 months). Two patients had delayed TIAs but long-term morbidity rate remained = 0%. At follow-up, occlusion was stable in 68% IAs, showed thrombosis in 12%, and recanalization in 20% IAs. Complementary treatment was required in 8% IAs. Final results showed 70% complete occlusions, 24% neck remnants, and 6% incomplete occlusions. Asymptomatic stent occlusion and significant stenosis occurred in one and two cases, respectively.

CONCLUSION

The Leo stent is safe and effective for treatment of wide-necked saccular IAs. Very long-term results show high rates of adequate and stable occlusion. Moreover, the stent is well tolerated.

Endovascular treatment of intracranial aneurysms with the Woven EndoBridge device: mid term and long term results

Purpose

To evaluate the clinical and anatomical results of treatment of intracranial aneurysms (IA) with the Woven EndoBridge (WEB) device, with emphasis on mid term and long term follow-up.

Methods

Between November 2010 and November 2015, we retrospectively identified, in our prospectively maintained database, all patients treated by WEB device placement for an IA at three institutions. Clinical charts, procedural data, and angiographic results were reviewed.

Results

48 patients with 49 IAs were identified. There were 35 women and 13 men with a mean age of 57 years (range 35–76 years). All IA were wide necked. Mean aneurysm size was 8.6 mm. There were 44 unruptured IA and 5 ruptured IA. During endovascular treatment (EVT), adjunctive devices were used in 22.4% of procedures. A good clinical outcome (modified Rankin Scale score ≤2) was achieved in 44/48 patients (92%). There was no mortality. Mean follow-up was 25 months (range 3–72 months; median 24 months). Between mid term and long term follow-up, occlusion was stable in 19/23 IA (82.6%), improved in 2/23 IA (8.7%), and worsened in 2/23 IA (8.7%). Retreatment was performed in 8/49 IA (16.3%). At the latest available follow-up, there were 34/47 (72.3%) complete occlusions and 13/47 (27.7%) neck remnants.

Conclusions

Our study suggests that EVT of IA with the WEB device provides adequate and stable long term occlusion.

Microneurosurgical Management of Posterior Communicating Artery Aneurysm: A Contemporary Series from Helsinki

OBJECTIVE

The objectives of this study were to analyze microsurgical techniques and to determine correlations between microsurgical techniques and the radiographic findings in the microneurosurgical treatment of posterior communicating artery aneurysms (PCoAAs).

METHODS

We retrospectively analyzed radiographic findings and videos of surgeries in 64 patients with PCoAAs who underwent microsurgical clipping by the senior author from August 2010 to 2014.

RESULTS

From 64 aneurysms, 30 (47%) had acute subarachnoid hemorrhage (SAH) that necessitated lamina terminalis fenestration (odds ratio [OR], 67.67; P < 0.001) and Liliequist membrane fenestration (OR, 19.62; P < 0.001). The low-lying aneurysms significantly necessitated the coagulation of the dura covering the anterior clinoid process (ACP) (OR, 7.43; P = 0.003) or anterior clinoidectomy (OR, 91.0; P < 0.001). We preferred straight clips in 45 (83%) of 54 posterolateral projecting aneurysms (OR, 45.0; P < 0.001), but preferred curved clips for posteromedial projecting aneurysms (OR, 6.39; P = 0.008). The mean operative time from the brain retraction to the final clipping was 17 minutes and 43 seconds. Postoperative computed tomography angiography revealed complete occlusion of 60 (94%) aneurysms. Three (4.6%) patients with acute SAH suffered postoperative lacunar infarction.

CONCLUSIONS

For ruptured aneurysms, lamina terminalis and Liliequist membrane fenestration are useful for additional cerebrospinal fluid drainage. For low-lying aneurysms, coagulation of the dura covering the ACP or tailored anterior clinoidectomy might be necessary for exposing the proximal aneurysm neck. Type of clips depends on the direction of projection. The microsurgical clipping of the PCoAAs can achieve good immediate complete occlusion rate with low postoperative stroke rate.

Coiling Is Not Superior to Clipping in Patients with High-Grade Aneurysmal Subarachnoid Hemorrhage: Systematic Review and Meta-Analysis

BACKGROUND

Outcomes of coiling embolization versus clipping for patients with high-grade aneurysmal subarachnoid hemorrhage (aSAH) have not been previously compared. We reviewed current evidence regarding the safety and efficacy of clipping versus coiling for high-grade aSAH.

METHODS

We conducted a meta-analysis of studies that compared clipping with coiling in patients with high-grade aSAH published from January 1999 to February 2016 in Medline, Embase, and Cochrane databases based on PRISMA inclusion and exclusion criteria. Binary outcome comparisons between clipping and coiling were described using odds ratios (ORs).

RESULTS

Three randomized controlled trials (RCTs) and 16 observational studies were included. There was no statistical difference in good outcome rates between the clipping and coiling groups (OR, 1.44; 95% confidence interval [CI], 0.97-2.13). Subgroup analysis showed no significant difference between the 2 treatments in non-RCTs (OR, 1.49; 95% CI, 0.95-2.36) and RCTs (OR, 1.15; 95% CI, 0.59-2.25). Coiling was associated with higher mortality (OR, 0.55; 95% CI, 0.41-0.75). Lower mortality was associated with clipping in non-RCTs (OR, 0.54; 95% CI, 0.40-0.74), but there was no difference in the RCTs (OR, 0.79; 95% CI, 0.19-3.39). Coiling was not associated with lower rates of complications including rebleeding (OR, 0.62; 95% CI, 0.30-1.29), ischemic infarct (OR, 0.89; 95% CI, 0.53-1.49), symptomatic vasospasm (OR, 0.76; 95% CI, 0.45-1.29), or shunt-dependent hydrocephalus (OR, 1.33; 95% CI, 0.52-3.40).

CONCLUSION

The outcome with coiling is not superior to clipping in patients with high-grade aSAH; moreover, coiling has a greater risk of mortality.

Predictors of recurrence after stent-assisted coil embolization of paraclinoid aneurysms

Stent-assisted coil embolization has been increasingly used to treat paraclinoid aneurysms. The study was aimed to evaluate safety and efficacy of stent-assisted coil embolization for paraclinoid aneurysms and explore the factors influencing the long-term outcomes. Under an institutional review board approved protocol, the clinical and angiographic data of 129 paraclinoid aneurysms in 120 patients (Male:Female=36:84; median age, 52years; range, 21-84) treated by stent-assisted coil embolization were reviewed retrospectively. Clinical status, aneurysmal morphology, treatment strategy and results were analyzed using Chi-squared tests in the univariate analysis and further analyzed using backward stepwise logistic regression. The univariate analysis indicated significance between the groups regarding hypertension, ruptured aneurysms, size, wide neck and immediate treatment results (P<0.05). Multivariate logistic regression analysis found that ruptured aneurysms (odds ratio [OR]=5.893, 95% confidence interval [CI], 1.512-23.054; p=0.011), larger size (OR=2.339; 95%CI, 1.148-4.781; p=0.020) and hypertension (OR=6.143; 95%CI, 1.560-24.183; p=0.009) might be predictors of recurrence. Stent-assisted coil embolization of paraclinoid aneurysm has a risk of recurrence. Ruptured aneurysms, larger size and hypertension may be the risk factors for recurrence.

Analysis of endovascular treatment of ruptured aneurysms of the middle cerebral artery compared to other anatomical locations

OBJECTIVE

The objective of this article is to compare the results of endovascular treatment of ruptured middle cerebral artery (MCA) aneurysms with ruptured aneurysms of other anatomic locations.

METHODS

Fifty consecutive ruptured aneurysms of the MCA and 209 aneurysms at other anatomical locations were selected retrospectively. We compared epidemiological, clinical and radiological variables, prognosis and complications.

RESULTS

The MCA aneurysms had a greater size and a poor dome/neck ratio. There were no significant differences in endovascular technique complications, occlusion rate or rebleeding between the two groups (p > 0.1). There were no significant differences in the mortality and number of dependent patients after one month.

CONCLUSION

The endovascular treatment of ruptured MCA aneurysms without hematoma is as safe and effective as other aneurysm localizations. Complication rates, occlusion rates and rebleeding of ruptured MCA aneurysms are comparable to other locations.

Preliminary Experience with the TransForm Occlusion Balloon Catheter: Safety and Potential Advantages

PURPOSE

Balloon-assisted coiling (BAC) has made the treatment of aneurysms with complex shape and broad neck possible, especially during the acute phase of hemorrhage. The authors present a prospective series of their preliminary experience with the TransForm occlusion balloon catheter (TOBC).

METHODS

Between September 2015 to February 2016 a total of 20 patients underwent endovascular treatment assisted by TOBC of which 19 had 20 untreated aneurysms and 1 patient harboring a meningioma was submitted to balloon test occlusion (BTO). The TOBC was used to perform BAC and BTO for the treatment of vasospasms and to cross the neck of giant aneurysms (anchor technique). All data regarding the feasibility and safety of treatment with the device were collected prospectively.

RESULTS

All patients completed treatment according to the modality previously chosen. The balloon was employed solely for remodeling in 17 patients, for anchor technique in 2, for both remodeling and vasospasm angioplasty in 1 and for BTO in 1 patient. The balloon could be navigated to the target aneurysm in all cases. Evaluation of postoperative anatomical results indicated total occlusion in 13 (72.2 %) aneurysms, neck remnants in 4 (22.2 %) and residual sac filling in 1 (5.5 %). There were two (9.5 %) complications related to treatment, all thromboembolic. No technical complications were observed.

CONCLUSION

The TOBC was shown to be safe and effective for the treatment of intracranial aneurysms with BAC. In addition, it was successfully employed to perform angioplasty for vasospasm and BTO. Finally, it was used in the balloon anchor technique for the first time.

Analysis of endovascular treatment of ruptured microaneurysms compared with ruptured larger aneurysms

Objective

To retrospectively analyze the complications and outcome of the endovascular treatment of ruptured microaneurysms compared with the treatment of ruptured larger aneurysms.

Methods

40 ruptured cerebral microaneurysms treated by endovascular techniques were selected retrospectively and compared with 207 larger ruptured cerebral aneurysms treated by endovascular techniques during the same time period. Medical charts and imaging studies were reviewed to analyze baseline clinical and epidemiologic characteristics, procedural complications, and clinical outcomes

Results

Cerebral microaneurysms had a higher incidence of intraoperative technical ruptures (13.5% vs 2.9%, p<0.005). The number of thromboembolic complications was not increased. Patient prognosis was similar for the two groups (mean modified Rankin Scale score 1.81 vs 2.09, p>0.1).

Conclusions

Coiling of cerebral microaneurysms has a reasonable safety profile with good clinical outcomes, similar to coiling of larger aneurysms. In our experience, the systematic use of remodeling balloons, operator experience, and the ability to manage complications are the reasons for the satisfactory results.

White-collar sign as a predictor of outcome after endovascular treatment for cerebral aneurysms

OBJECTIVE The white-collar sign (WCS) is known as a thick neointimal tissue formation at the aneurysm neck after endovascular coil embolization of cerebral aneurysms, which may prevent aneurysm recanalization. The purpose of this study was to evaluate factors involved in the appearance of WCS and to identify radiological and clinical outcomes of treated aneurysms with WCS. METHODS The study included 140 patients with 149 aneurysms in which it was possible to confirm the aneurysm neck between the aneurysm sac and parent artery by using conventional angiography. The WCS was defined as a radiolucent band at the aneurysm neck on the angiogram at 6 months after initial embolization. The radiological outcome was evaluated using MR angiography. RESULTS In 23 of 149 aneurysms (15.4%), a WCS appeared. The WCS-positive group had a significantly smaller neck size (3.3 ± 0.8 mm vs 4.2 ± 1.1 mm, p < 0.001) and smaller aneurysm size (4.3 ± 0.9 mm vs 6.0 ± 2.1 mm, p < 0.001) than the WCS-negative group. Multivariate analysis revealed that WCS appearance was associated with small neck size (OR 0.376, 95% CI 0.179-0.787; p = 0.009). In 106 of 149 aneurysms, the rate of complete occlusion was significantly higher in the WCS-positive group (18/18, 100%) than in the WCS-negative group (n = 54/88, 61.4%; p = 0.001) in the mean follow-up period of 31.0 ± 9.7 months (range 5-52 months). Neither major recanalization nor rupture of the aneurysm occurred in the WCS-positive group. CONCLUSIONS Appearance of the WCS was associated with complete occlusion and good clinical outcome after endovascular coil embolization. The WCS would help to determine the prognosis of cerebral aneurysms after endovascular treatment.

Large Residual Volume, Not Low Packing Density, Is the Most Influential Risk Factor for Recanalization after Coil Embolization of Cerebral Aneurysms

Background

Tight coil packing with density of at least 20%–25% is known to be important for preventing recanalization after embolization of cerebral aneurysms. However, large aneurysms sometimes recanalize regardless of the packing density, suggesting that the absolute residual volume which is determined by aneurysm volume and packing density may be more important risk factor for recanalization. To validate this hypothesis, we analyzed the factors affecting the outcomes of treated aneurysms at our institute.

Methods and Findings

We included 355 small and large aneurysms. The following six factors were obtained from every case: aneurysm volume (mL), neck size (mm), packing density (%), residual volume (mL), rupture status at presentation, and stent assistance (with or without stent). The data were then subjected to multivariate logistic regression analysis to identify significant risk factors for recanalization. Recanalization occurred in 61 aneurysms (17.2%). Significant predictors for recanalization were aneurysm volume (odds ratio, 15.3; P < 0.001) and residual volume (odds ratio, 30.9; P < 0.001), but not packing density (odds ratio, 0.98; P = 0.341). These results showed that for each 0.1-mL increase in aneurysm volume and residual volume, the risk of recanalization increased by 1.3 times and 1.4 times, respectively.

Conclusions

The most influential risk factor for recanalization after coil embolization was residual volume, not packing density. The larger the aneurysm volume, the greater the packing density has to be to minimize the residual volume and risk of recanalization. Since tight coil packing has already been aimed, further innovation of coil property or embolization technique may be needed. Otherwise, different treatment modality such as flow diverter or parent artery occlusion may have to be considered.

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.