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Background: Flow diversion has revolutionized the management of wide-necked intracranial aneurysms (IAs). We aimed to assess the effectiveness and safety of the new generation 64-wire Surpass Evolve for the treatment of unruptured small/medium-sized IAs., Methods and Results: This is a subanalysis from the SEASE (Safety and Effectiveness Assessment of the Surpass Evolve) registry, an observational cohort study including 15 academic institutions in North America and Europe between July 2020 and October 2022. Patients with wide-necked saccular IAs, measuring <12 mm along the internal carotid artery and vertebrobasilar system, and treated with the Surpass Evolve were included. Primary effectiveness was complete occlusion (Raymond-Roy class 1) at follow-up (core laboratory adjudicated), and primary safety was major stroke (ischemic/hemorrhagic) in the territory supplied by the target artery or death. A total of 129 cases with 135 IAs were included (median age 59 years, 85.3% women). Median maximum IAs size and neck size were 5.1 and 3.9 mm, respectively. Most IAs were in the internal carotid artery C6 (65.9%, 89/135) and C7 (14.1%, 19/135) segments. At a median follow-up time of 10.2 months (interquartile range, 6.4-12.8), complete occlusion was 77.1% (101/131), ≥50% in-stent stenosis was 8.8% (11/125), and retreatment was 0.8% (1/125). Major stroke and mortality were reported in 2 (1.6%) patients and 1 (0.8%) patient, respectively. Size was the only factor associated with higher odds of incomplete occlusion (adjusted odds ratio, 1.2 [95% CI, 1.02-1.5]; P =0.03)., Conclusions: Patients with small/medium-sized IAs can be effectively treated using the Surpass Evolve, a new generation, 64-wire, cobalt-chromium flow diverter.

Introduction: The Woven EndoBridge (WEB) device is emerging as a novel therapy for intracranial aneurysms, but its use for off-label indications requires further study. Using machine learning, we aimed to develop predictive models for complete occlusion after off-label WEB treatment and to identify factors associated with occlusion outcomes., Methods: This multicenter, retrospective study included 162 patients who underwent off-label WEB treatment for intracranial aneurysms. Baseline, morphological, and procedural variables were utilized to develop machine-learning models predicting complete occlusion. Model interpretation was performed to determine significant predictors. Ordinal regression was also performed with occlusion status as an ordinal outcome from better (Raymond Roy Occlusion Classification [RROC] grade 1) to worse (RROC grade 3) status. Odds ratios (OR) with 95 % confidence intervals (CI) were reported., Results: The best performing model achieved an AUROC of 0.8 for predicting complete occlusion. Larger neck diameter and daughter sac were significant independent predictors of incomplete occlusion. On multivariable ordinal regression, higher RROC grades (OR 1.86, 95 % CI 1.25-2.82), larger neck diameter (OR 1.69, 95 % CI 1.09-2.65), and presence of daughter sacs (OR 2.26, 95 % CI 0.99-5.15) were associated with worse aneurysm occlusion after WEB treatment, independent of other factors., Conclusion: This study found that larger neck diameter and daughter sacs were associated with worse occlusion after WEB therapy for aneurysms. The machine learning approach identified anatomical factors related to occlusion outcomes that may help guide patient selection and monitoring with this technology. Further validation is needed., Competing Interests: Declaration of competing interest None., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: To evaluate the effect of procedure time on thrombectomy outcomes in different subpopulations of patients undergoing endovascular thrombectomy (EVT), given the recently expanded indications for EVT., Methods: This multicenter study included patients undergoing EVT for acute ischemic stroke at 35 centers globally. Procedure time was defined as time from groin puncture to successful recanalization (Thrombolysis in Cerebral Infarction score ≥2b) or abortion of procedure. Patients were stratified based on stroke location, use of IV tissue plasminogen activator (tPA), Alberta Stroke Program Early CT score, age group, and onset-to-groin time. Primary outcome was the 90-day modified Rankin Scale (mRS) score, with scores 0-2 designating good outcome. Secondary outcome was postprocedural symptomatic intracranial hemorrhage (sICH). Multivariate analyses were performed using generalized linear models to study the impact of procedure time on outcomes in each subpopulation., Results: Among 8961 patients included in the study, a longer procedure time was associated with higher odds of poor outcome (mRS score 3-6), with 10% increase in odds for each 10 min increment. When procedure time exceeded the 'golden hour', poor outcome was twice as likely. The golden hour effect was consistent in patients with anterior and posterior circulation strokes, proximal or distal occlusions, in patients with large core infarcts, with or without IV tPA treatment, and across age groups. Procedures exceeding 1 hour were associated with a 40% higher sICH rate. Posterior circulation strokes, delayed presentation, and old age were the variables most sensitive to procedure time., Conclusions: In this work we demonstrate the universality of the golden hour effect, in which procedures lasting more than 1 hour are associated with worse clinical outcomes and higher rates of sICH across different subpopulations of patients undergoing EVT., Competing Interests: Competing interests: CMC: Consultant-Silk Road, Penumbra, Microvention, Cerevasc, Stryker, Speaker-Silk Road, Penumbra; AMS: Consultant- Stryker, Penumbra, Terumo, RapidAI; PJ: Consultant-Balt, Cerus, Microvention, Medtronic; M-NP: Honoraria - Stryker, Medtronic, Penumbra, Acandis, Phenox, Siemens Healthineers, Research Support-Swiss National Science Foundation, Bangerter-Rhyner Stiftung, Stryker, Phenox, Medtronic, Rapid, Penumbra, Siemens Healthineer; RDL: Research funding: Hyprevention, Kaneka Medical, Siemens Healthineers, SNIS foundation; Consultant: Stryker Neurovascular, imperative care, Cerenovus, Asahi Intec; Stock: synchron, endostream, Q’Apel, spartan micro; PK: Consultant: Stryker, Microvention, Imperative Care; AJP: Consultant: Stryker, Depuy Synthes; ASA: Research grants: Balt, Medtronic, Microvention, Penumbra and Siemens; Consultant: Arsenal, Balt, Johnson and Johnson, Medtronic, Microvention, Penumbra, Scientia, Siemens, Stryker; Shareholder: Azimuth, Bendit, Cerebrotech, Endostream, Magneto, Mentice, Neurogami, Neuros, Scientia, Serenity, Synchron, Tulavi, Vastrax, VizAI; MRL: Research grants: Stryker, Medtronic; Consultant: Medtronic, Aeaean Advisers; Shareholder: Hyperion Surgical, Proprio, Synchron, Cerebrotech, Fluid Biomed, Stereotaxis; SIT: Consultant: Microvention, Medtronic; JAG: Grant support- Georgia Research Alliance, Department of Defense, Emory Medical Care Foundation, Neurosurgery Catalyst, Stock- NTI, Cognition, AA: Research grants: NIH, AHA, Department of VA., (© Author(s) (or their employer(s)) 2024. No commercial re-use. See rights and permissions. Published by BMJ.)

Endovascular surgical neuro-oncology is a relatively new subspecialty which uses endovascular neuro-interventional techniques for the management of nervous system tumors and tumor-related vascular conditions. Although there are several endovascular procedures that are widely available as standard-of-care diagnostic and treatment adjuncts, there has been a renewed interest to explore endovascular approaches as a means for selective intra-arterial delivery of therapeutic agents to nervous system tumors, including methods for opening the blood brain and blood tumor barriers. In this review, we discuss the historical development of various forms of endovascular intra-arterial treatment for tumors over the past 40 years, summarize endovascular approaches that are currently being employed, and highlight current clinical trials., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background and Objectives: The impact of race on outcomes in the treatment of intracranial aneurysm (IA) remains unclear. We aimed to investigate the relationship between race classified into White, Black, Hispanic, and other and treatment outcomes in patients with ruptured and unruptured IAs., Methods: The study population consisted of 2836 patients with IA with endovascular treatment or microsurgical treatment (MST) from 16 centers in the United States and Asia, all participating in the observational "STAR" registry. The primary outcome was a 90-day modified Rankin Scale of 0 to 2. Secondary outcomes included periprocedural cerebral infarction and intracranial hemorrhage, perioperative symptomatic cerebral vasospasm in ruptured IA and mortality, and all causes of mortality within 90 days., Results: One thousand fifty-three patients were White (37.1%), 350 were Black (12.3%), 264 were Hispanic (9.3%), and 1169 were other (41.2%). Compared with White patients, Hispanic patients had a significantly lower proportion of primary outcome (adjusted odds ratio [aOR] 0.36, 95% CI, 0.23-0.56) and higher proportion of the periprocedural cerebral infarction, perioperative mortality, and all causes of mortality (aOR 2.53, 95% CI, 1.40-4.58, aOR 1.84, 95% CI, 1.00-3.38, aOR 1.83, 95% CI, 1.06-3.17, respectively). Outcomes were not significantly different in Black and other patients. The subgroup analysis showed that Hispanic patients with age ≥65 years (aOR 0.19, 95% CI, 0.10-0.38, interaction P = .048), Hunt-Hess grades 0 to 3 (aOR 0.29, 95% CI, 0.19-0.46, interaction P = .03), and MST (aOR 0.24, 95% CI, 0.13-0.44, interaction P = .04) had a significantly low proportion of primary outcome., Conclusion: This study demonstrates that Hispanic patients with IA are more likely to have a poor outcome at 90 days after endovascular treatment or MST than White patients. Physicians have to pay attention to the selection of treatment modalities, especially for Hispanic patients with specific factors to reduce racial discrepancies., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Background: The definitive impact of onset to arterial puncture time (OPT) on 90-day mortality after endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS) caused by anterior circulation large vessel occlusion (LVO) remains unknown. The present study aimed to evaluate the influence of OPT on 90-day mortality in anterior circulation AIS-LVO patients who underwent EVT., Methods: Data from 33 international centers were retrospectively analyzed. The receiver operating characteristic curve analysis was used to identify a cutoff for OPT. A propensity score-matched analysis was performed. The primary outcome was 90-day mortality (modified Rankin Scale [mRS] 6). Secondary outcomes included mortality at discharge, 90-day good outcome (mRS 0-2), 90-day poor outcome (mRS 5-6), successful recanalization (defined as postprocedure modified Thrombolysis in Cerebral Infarction scale ≥2b), and intracranial hemorrhage., Results: A total of 2842 AIS-LVO patients with EVT were included. The cutoff for OPT for 90-day mortality was 180 min. Of these 378 patients had OPT <180 min and 378 patients had OPT ≥180 min in the propensity score-matched cohort (n = 756). Patients with OPT <180 min were less likely to have 90-day mortality (odds ratio [OR] 0.70, 95% confidence interval [CI] 0.51-0.96) and poor outcome (OR 0.71, 95% CI 0.53-0.96), and more likely to have 90-day good outcome (OR 1.55, 95% CI 1.16-2.08). Other outcomes showed no significant differences., Conclusions: This study showed that OPT <180 min was less related to 90-day mortality and poor outcome, and more to 90-day good outcome in AIS-LVO patients who underwent EVT., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Endovascular thrombectomy(EVT) is the standard of care for large vessel occlusion(LVO) stroke. Data on technical and clinical outcome in proximal medium vessel occlusions(pMeVOs) comparing frontline techniques remain limited., Methods: We report an international multicenter retrospective study of patients undergoing EVT for stroke at 32 centers between 2015-2021. Patients were divided into LVOs(ICA/M1/Vertebrobasilar) or pMeVOs(M2/A1/P1) and categorized by thrombectomy technique. Primary outcome was 90-day good functional outcome(mRS ≤ 2). Multivariate logistic regressions were used to evaluate the impact of technical variables on clinical outcomes. Propensity score matching was used to compare outcome in patients with pMeVO treated with aspiration versus stent-retriever., Results: In the cohort of 5977 LVO and 1287 pMeVO patients, pMeVO did not independently predict good-outcome(p  =  0.55). In pMeVO patients, successful recanalization irrespective of frontline technique(aOR = 3.2,p < 0.05), procedure time ≤ 1-h(aOR = 2.2,p < 0.05), and thrombectomy attempts ≤ 4(aOR =  2.8,p < 0.05) were independent predictors of good-outcomes.In a propensity-matched cohort of aspiration versus stent-retriever pMeVO patients, there was no difference in good-outcomes. The rates of hemorrhage were higher(9%vs.4%,p < 0.01) and procedure time longer(51-min vs. 33-min,p < 0.01) with stent-retriever, while the number of attempts was higher with aspiration(2.5vs.2,p < 0.01). Rates of hemorrhage and good-outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group compared to attempts in the stent-retriever group., Conclusions: Clinical outcomes following EVT for pMeVO are comparable to those in LVOs. The golden hour or 3-pass rules in LVO thrombectomy still apply to pMeVO thrombectomy. Different techniques may exhibit different futility metrics; SR thrombectomy was more influenced by attempts whereas aspiration was more dependent on procedure time., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The Woven EndoBridge (WEB) device is primarily used for treating wide-neck intracranial bifurcation aneurysms under 10 mm. Limited data exists on its efficacy for large aneurysms. We aim to assess angiographic and clinical outcomes of the WEB device in treating large versus small aneurysms. We conducted a retrospective review of the WorldWide WEB Consortium database, from 2011 to 2022, across 30 academic institutions globally. Propensity score matching (PSM) was employed to compare small and large aneurysms on baseline characteristics. A total of 898 patients were included. There was no significant difference observed in clinical presentations, smoking status, pretreatment mRS, presence of multiple aneurysms, bifurcation location, or prior treatment between the two groups. After PSM, 302 matched pairs showed significantly lower last follow-up adequate occlusion rates (81% vs 90%, p = 0.006) and higher retreatment rates (12% vs 3.6%, p < 0.001) in the large aneurysm group. These findings may inform treatment decisions and patient counseling. Future studies are needed to further explore this area., (© 2024. The Author(s).)

Objective: This study was conducted to investigate the impact of antiplatelet administration in the periprocedural period on the occurrence of thromboembolic complications (TECs) in patients undergoing treatment using the Woven EndoBridge (WEB) device for intracranial wide-necked bifurcation aneurysms. The primary objective was to assess whether the use of antiplatelets in the pre- and postprocedural phases reduces the likelihood of developing TECs, considering various covariates., Methods: A retrospective multicenter observational study was conducted within the WorldWideWEB Consortium and comprised 38 academic centers with endovascular treatment capabilities. Univariable and multivariable logistic regression analyses were performed to determine the association between antiplatelet use and TECs, adjusting for covariates. Missing predictor data were addressed using multiple imputation., Results: The study comprised two cohorts: one addressing general thromboembolic events and consisting of 1412 patients, among whom 103 experienced TECs, and another focusing on symptomatic thromboembolic events and comprising 1395 patients, of whom 50 experienced symptomatic TECs. Preprocedural antiplatelet use was associated with a reduced likelihood of overall TECs (OR 0.32, 95% CI 0.19-0.53, p < 0.001) and symptomatic TECs (OR 0.49, 95% CI 0.25-0.95, p = 0.036), whereas postprocedural antiplatelet use showed no significant association with TECs. The study also revealed additional predictors of TECs, including stent use (overall: OR 4.96, 95% CI 2.38-10.3, p < 0.001; symptomatic: OR 3.24, 95% CI 1.26-8.36, p = 0.015), WEB single-layer sphere (SLS) type (overall: OR 0.18, 95% CI 0.04-0.74, p = 0.017), and posterior circulation aneurysm location (symptomatic: OR 18.43, 95% CI 1.48-230, p = 0.024)., Conclusions: The findings of this study suggest that the preprocedural administration of antiplatelets is associated with a reduced likelihood of TECs in patients undergoing treatment with the WEB device for wide-necked bifurcation aneurysms. However, postprocedural antiplatelet use did not show a significant impact on TEC occurrence.

Purpose: Our purpose was to assess the efficacy and safety of the pRESET LITE stent retriever (Phenox, Bochum, Germany), designed for medium vessel occlusion (MeVO) in acute ischemic stroke (AIS) patients with a primary MeVO., Methods: We performed a retrospective analysis of the MAD MT Consortium, an integration of prospectively maintained databases at 37 academic institutions in Europe, North America, and Asia, of AIS patients who underwent mechanical thrombectomy with the pRESET LITE stent retriever for a primary MeVO. We subcategorized occlusions into proximal MeVOs (segments A1, M2, and P1) vs. distal MeVOs/DMVO (segments A2, M3-M4, and P2). We reviewed patient and procedural characteristics, as well as angiographic and clinical outcomes., Results: Between September 2016 and December 2021, 227 patients were included (50% female, median age 78 [65-84] years), of whom 161 (71%) suffered proximal MeVO and 66 (29%) distal MeVO. Using a combined approach in 96% of cases, successful reperfusion of the target vessel (mTICI 2b/2c/3) was attained in 85% of proximal MeVO and 97% of DMVO, with a median of 2 passes (IQR: 1-3) overall. Periprocedural complications rate was 7%. Control CT at day 1 post-MT revealed a hemorrhagic transformation in 63 (39%) patients with proximal MeVO and 24 (36%) patients with DMVO, with ECASS-PH type hemorrhagic transformations occurring in 3 (1%) patients. After 3 months, 58% of all MeVO and 63% of DMVO patients demonstrated a favorable outcome (mRS 0-2)., Conclusion: Mechanical thrombectomy using the pRESET LITE in a combined approach with an aspiration catheter appears effective for primary medium vessel occlusions across several centers and physicians., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The Woven EndoBridge (WEB) devices have been used for treating wide neck bifurcation aneurysms (WNBAs) with several generational enhancements to improve clinical outcomes. The original device dual-layer (WEB DL) was replaced by a single-layer (WEB SL) device in 2013. This study aimed to compare the effectiveness and safety of these devices in managing intracranial aneurysms., Methods: A multicenter cohort study was conducted, and data from 1,289 patients with intracranial aneurysms treated with either the WEB SL or WEB DL devices were retrospectively analyzed. Propensity score matching was utilized to balance the baseline characteristics between the two groups. Outcomes assessed included immediate occlusion rate, complete occlusion at last follow-up, retreatment rate, device compaction, and aneurysmal rupture., Results: Before propensity score matching, patients treated with the WEB SL had a significantly higher rate of complete occlusion at the last follow-up and a lower rate of retreatment. After matching, there was no significant difference in immediate occlusion rate, retreatment rate, or device compaction between the WEB SL and DL groups. However, the SL group maintained a higher rate of complete occlusion at the final follow-up. Regression analysis showed that SL was associated with higher rates of complete occlusion (OR: 0.19; CI: 0.04 to 0.8, p = 0.029) and lower rates of retreatment (OR: 0.12; CI: 0 to 4.12, p = 0.23)., Conclusion: The WEB SL and DL devices demonstrated similar performances in immediate occlusion rates and retreatment requirements for intracranial aneurysms. The SL device showed a higher rate of complete occlusion at the final follow-up., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background and Objectives: Some studies have shown that female patients had a poorer prognosis after endovascular treatment for ruptured intracranial aneurysm than male patients. However, data have been sparse regarding differences in the periprocedural and perioperative complication rate with ruptured and unruptured intracranial aneurysms., Methods: This retrospective cohort study used data from the Stroke Thrombectomy and Aneurysm Registry, a database of 9 institutions in the United States, Europe, and Asia. The study presented intracranial aneurysms after microsurgical and/or endovascular treatment from January 1, 2013, to December 31, 2022. The primary outcome was incidence of periprocedural cerebral infarction. Secondary outcomes were periprocedural intracranial hemorrhage, periprocedural mortality, perioperative vasospasm, and functional outcome at 90 days after procedure., Results: Among 3342 patients with aneurysm, 2447 were female and 857 were male, and the mean age of female and male patients was 59.6 and 57.1 years, respectively. Current smoker, family history of aneurysm, and ruptured aneurysm were observed in 23.5% vs 35.7 %, 10.8 % vs 5.7%, and 28.2% vs 40.5% of female and male patients, respectively. In female patients, internal carotid artery aneurysms were more commonly observed (31.1% vs 17.3%); however, anterior cerebral artery aneurysms were less commonly observed (18.5% vs 33.8%) compared with male patients. Periprocedural cerebral infarction rate was lower in female than male patients (2.4% vs 4.4%; P = .002). The adjusted odds ratio of primary outcome of female to male patients was 0.72 (95% CI, 0.46-1.12). Incidence of periprocedural intracranial hemorrhage and periprocedural mortality and perioperative symptomatic vasospasm and functional outcome was similar in both groups. In subgroup analysis, periprocedural cerebral infarction due to microsurgical treatment occurred frequently in male patients while incidence in endovascular treatment was similar in both groups (interaction P = .005)., Conclusion: This large multicenter registry of patients undergoing intracranial aneurysm treatment found that female patients were not at increased risk of perioperative complications., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background: Recent clinical trials have shown that mechanical thrombectomy is superior to medical management for large vessel occlusion for up to 24 hours from onset. Our objective is to examine the safety and efficacy of thrombectomy beyond the standard of care window., Methods: A retrospective review was undertaken of the multicenter Stroke Thrombectomy and Aneurysm Registry (STAR). We identified patients who underwent mechanical thrombectomy for large vessel occlusion beyond 24 hours. We selected a matched control group from patients who underwent thrombectomy in the 6-24-hour window. We used functional independence at 3 months as our primary outcome measure., Results: We identified 121 patients who underwent thrombectomy beyond 24 hours and 1824 in the 6-24-hour window. We selected a 2:1 matched group of patients with thrombectomy 6-24 hours as a comparison group. Patients undergoing thrombectomy beyond 24 hours were less likely to be independent at 90 days (18 (18.8%) vs 73 (34.9%), P=0.005). They had higher odds of mortality at 90 days in the adjusted analysis (OR 2.34, P=0.023). Symptomatic intracerebral hemorrhage and other complications were similar in the two groups. In a multivariate analysis only lower number of attempts was associated with good outcomes (OR 0.27, P=0.022)., Conclusions: Mechanical thrombectomy beyond 24 hours appears to be safe and tolerable with no more hemorrhages or complications compared with standard of care thrombectomy. Outcomes and mortality in this time window are worse compared with an earlier time window, but the rates of good outcomes may justify this therapy in selected patients., Competing Interests: Competing interests: PK: consultant for Stryker NV and Imperative Care. On the editorial board of JNIS. DRG: Balt Italy: Consultant, Microvention Europe: Consultant, Penumbra Inc: Consultant. AMS: Penumbra: Research support, Consultant. Stryker: Research support, Consultant. Cerenovus: Consultant. Terumo: Consultant. IschemaView Inc/Rapid AI: Research support, Consultant. ASA: Consultant for Arsenal, Balt, Johnson and Johnson, Medtronic, Microvention, Penumbra, Scientia, Siemens, Stryker Research support from Balt, Medtronic, Microvention, Penumbra and Siemens Shareholder Azimuth, Bendit, Cerebrotech, Endostream, Magneto, Mentice, Neurogami, Serenity, Synchron, Triad Medical, Vastrax, VizAI. RDL: Consultant - Imperative Care, Stryker, Cerenovus, Spartan Micro. Research support – Siemens. On the editorial board of JNIS. ML: On the editorial board of JNIS. MM: On the editorial board of JNIS. JM: Consultant Stryker. On the editorial board of JNIS. MSP: Clinical Events Committee/Consultant for Medtronic. AP: consultant for Stryker and Depuy Synthes. ES: Consultant for Medtronic/Microvention/Rapid Medical., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Over the last 2 decades, the field of transcriptomics has emerged as a major subdiscipline in biology. Transcriptomic techniques have been used by many groups over this time to better understand intracranial aneurysm development, rupture, and treatment. However, only a few studies have applied transcriptomics to understand the mechanisms behind flow diversion (FD) specifically, despite its increasing importance in the neurointerventional armamentarium. FD is an increasingly safe and effective treatment option for intracranial aneurysms. However, the clinical understanding and use of FD has far outpaced the understanding of the underlying mechanisms. To make FD more predictable, clinically efficacious, and safe, it is important to understand the biological mechanisms at play that lead to successful and unsuccessful FD. In this review, the authors focus on the current understanding of FD biology, the recent advances in transcriptomics, and what future studies could be performed to deepen the understanding of FD. They propose the new concept of the FD microenvironment to be studied, which may unlock a deeper biological understanding. This review provides the background for prospective studies into the development of targeted aneurysm therapy, whether by modified devices or by medical adjuncts.

Objective: The Woven EndoBridge (WEB) device is an intrasaccular flow disruptor designed for wide-necked bifurcation aneurysms. These aneurysms may require the use of a concomitant stent. The objective of this study was to determine the clinical and radiological outcomes of patients undergoing stent-assisted WEB treatment. In addition, the authors also sought to determine the predictors of a concomitant stent in aneurysms treated with the WEB device., Methods: The data for this study were taken from the WorldWideWEB Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups based on treatment: stent-assisted WEB and WEB device alone. The authors compared clinical and radiological outcomes of both groups. Univariable and multivariable binary logistic regression analyses were performed to determine factors that predispose to stent use., Results: The study included 691 intracranial aneurysms (31 with stents and 660 without stents) treated with the WEB device. The adequate occlusion status did not differ between the two groups at the latest follow-up (83.3% vs 85.6%, p = 0.915). Patients who underwent stenting had more thromboembolic (32.3% vs 6.5%, p < 0.001) and procedural (16.1% vs 3.0%, p < 0.001) complications. Aneurysms treated with a concomitant stent had wider necks, greater heights, and lower dome-to-neck ratios. Increasing neck size was the only significant predictor for stent use., Conclusions: This study demonstrates that there is no difference in the degree of aneurysm occlusion between the two groups; however, complications were more frequent in the stent group. In addition, a wider aneurysm neck predisposes to stent assistance in WEB-treated aneurysms.

Background: Flow diverters (FDs) have demonstrated a safe and effective profile. However, the use of FDs for posterior communicating artery (PComA) aneurysms remains controversial., Objective: To evaluate the safety and effectiveness of FDs for PComA aneurysms using a systematic review and meta-analysis of the literature., Methods: We performed a systematic search from inception until June 2022 for flow diversion in PComA aneurysms. Primary effectiveness was the rate of complete aneurysm occlusion defined by Raymond-Roy class 1. Primary safety outcomes were treatment-related ischemic/hemorrhagic (composite) events causing morbidity and mortality. Secondary safety was PComA patency at follow-up. Random-effects meta-analyses were used to calculate proportions, and statistical heterogeneity was assessed., Results: A total of 13 studies with 397 patients harboring 403 aneurysms were included. Mean age was 48 years, and the mean aneurysm size was 5.3 mm. Most aneurysms were unruptured (65%). Complete occlusion at final follow-up was 73% (CI 66%-79%), and adjunctive coils were used in 10% of aneurysms. Retreatment rate was 2% (CI 0%-9%). The primary safety composite outcome was 4% (CI 3%-7%), and mortality was 1%. PComA patency at final follow-up was 76% (CI 57%-89%). Subgroup analysis, patients with fetal PComAs had a lower complete occlusion rate (42% fetal PComA vs 77%, psubgroupdifference = <.01)., Conclusion: The performance of FDs in PComA aneurysms is comparable with outcomes found in other subtypes of supraclinoid aneurysms. Effectiveness was acceptable and safety favorable. However, effectiveness was suboptimal in patients with fetal-type PComAs; alternative treatments should be considered in these cases., (Copyright © Congress of Neurological Surgeons 2023. All rights reserved.)

Background and Purpose: Flow diversion has established as standard treatment for intracranial aneurysms, the Surpass Streamline is the only FDA-approved braided cobalt/chromium alloy implant with 72-96 wires. We aimed to determine the safety and efficacy of the Surpass in a post-marketing large United States cohort., Materials and Methods: This is a retrospective multicenter study of consecutive patients treated with the Surpass for intracranial aneurysms between 2018 and 2021. Baseline demographics, comorbidities, and aneurysm characteristics were collected. Efficacy endpoint included aneurysm occlusion on radiographic follow-up. Safety endpoints were major ipsilateral ischemic stroke or treatment-related death., Results: A total of 277 patients with 314 aneurysms were included. Median age was 60 years, 202 (73%) patients were females. Hypertension was the most common comorbidity in 156 (56%) patients. The most common location of the aneurysms was the anterior circulation in 89% (279/314). Mean aneurysm dome width was 5.77 ± 4.75 mm, neck width was 4.22 ± 3.83 mm, and dome/neck ratio was 1.63 ± 1.26. Small-sized aneurysms were 185 (59%). Single device was used in 94% of the patients, mean number of devices per patient was 1.06. At final follow-up, complete obliteration rate was 81% (194/239). Major stroke and death were encountered in 7 (3%) and 6 (2%) cases, respectively., Conclusion: This is the largest cohort study using a 72-96 wire flow diverter. The Surpass Streamline demonstrated a favorable safety and efficacy profile, making it a valuable option for treating not only large but also wide-necked small and medium-sized intracranial aneurysms.

Background: The Woven EndoBridge (WEB) device is a novel intrasaccular flow disruptor tailored for bifurcation aneurysms. We aim to describe the degree of aneurysm occlusion at the latest follow-up, and the rate of complications of aneurysms treated with the WEB device stratified according to rupture status., Methods: Our data were taken from the WorldWideWeb Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups: ruptured and unruptured. We compared clinical and radiologic outcomes of both groups. Propensity score matching (PSM) was done to match according to age, gender, bifurcation, location, prior treatment, neck, height, dome width, daughter sac, incorporated branch, pretreatment antiplatelets, and last imaging follow-up., Results: The study included 676 patients with 691 intracranial aneurysms (529 unruptured and 162 ruptured) treated with the WEB device. The PSM analysis had 55 pairs. In both the unmatched (85.8% vs 84.3%, p=0.692) and matched (94.4% vs 83.3%, p=0.066) cohorts there was no significant difference in the adequate occlusion rate at the last follow-up. Likewise, there were no significant differences in both ischemic and hemorrhagic complications between the two groups. There was no documented aneurysm rebleeding after WEB device implantation., Conclusion: There was no significant difference in both the radiologic outcomes and complications between unruptured and ruptured aneurysms. Our findings support the feasibility of treatment of ruptured aneurysms with the WEB device., Competing Interests: Competing interests: JDBD: Honoraria from Medtronic. Travel grant from Microvention. MD: No relevant relationships NA: No relevant relationships RWR: Grants from National Institutes of Health, Heitman foundation, Society of vascular and interventional neurology; Advisory board participation for Rapid medical; Site PI for Microvention and Penumbra JEV: No relevant relationships AG : No relevant relationships SVL: No relevant relationships LR: No relevant relationships AAB: No relevant relationships ES: No relevant relationships KP: No relevant relationships KEL: No relevant relationships GS : No relevant relationships MAM: No relevant relationships IL: No relevant relationships PMR: No relevant relationships JAV: Fees from MicroVention for proctoring cases for new physician users of the Woven EndoBridge device; Medtronic travel expense VŽ: Participation on the data safety monitoring board or advisory board for KBC Sestre Milosrdnice, Zagreb / OB Nova Gradiška MUH: No relevant relationships CR: No relevant relationships HR: No relevant relationships VMT: No relevant relationships SM: No relevant relationships SG: No relevant relationships PH: No relevant relationships NA: No relevant relationships JDR: No relevant relationships YR: No relevant relationships CMS: No relevant relationships OG: No relevant relationships MP: No relevant relationships ALK: No relevant relationships CM: No relevant relationships SE: No relevant relationships RMS: Supported by the NREF, Joe Niekro Foundation, Brain Aneurysm Foundation, Bee Foundation, and the National Institutes of Health (R01NS111119-01A1, UL1TR002736, and KL2TR002737) through the Miami Clinical and Translational Science Institute, from the National Center for Advancing Translational Sciences and the National Institute on Minority Health and Health Disparities. AH: Consulting or speaker fees from Medtronic, MicroVention, Stryker, Penumbra, Cerenovus, Genentech, GE Healthcare, Scientia, Balt, Viz.ai, Insera Therapeutics, Proximie, NeuroVasc, NovaSignal, Vesalio, and Galaxy Therapeutics. AS: No relevant relationships AN: No relevant relationships JJ: Consulting and speaker fees from Cerenovus MP: No relevant relationships JS: No relevant relationships CPF: No relevant relationships MBB: No relevant relationships MM: Grants from Balt, Medtronic, MicroVention, and Stryker. MMS: No relevant relationships JB: No relevant relationships BTJ: No relevant relationships RAD: No relevant relationships TH: No relevant relationships RT: Medtronic Stocks CU: No relevant relationships BL : No relevant relationships PP: No relevant relationships ASP: Grants from NIH, Microvention, Cerenovus, Medtronic and Stryker; Consulting fees from Neurovascular, Stryker NeurovascularBalt, Q’Apel Medical, Cerenovus, Microvention, Imperative Care, Agile, Merit, CereVasc and Arsenal Medical; stock options from InNeuroCo, Agile, Perfuze, Galaxy and NTI GP: No relevant relationships CJG: Grants to institution from Medtronic and Penumbra; consulting fees from Stryker and MicroVention. HA: Proctoring fees from MicroVention. Grants to institution from the National Institutes of Health; consulting fees from Amnis Therapeutics, Apellis Pharmaceuticals, Boston Scientific, Canon Medical Systems, Cardinal Health 200, Cerebrotech Medical Systems, Cerenovus, Cerevatech Medical, Cordis, Corindus, EndoStream Medical, Imperative Care, Integra, IRRAS, Medtronic, MicroVention, Minnetronix Neuro, Penumbra, Q’Apel Medical, Rapid Medical, Serenity Medical, Silk Road Medical, StimMed, Stryker Neurovascular, Three Rivers Medical, VasSol, Viz.ai, and W.L. Gore & Associates; payment for participation on the steering committees for the Cerenovus EXCELLENT and ARISE II Trial; Medtronic SWIFT PRIME, VANTAGE, EMBOLISE, and SWIFT DIRECT Trials; MicroVention FRED Trial and CONFIDENCE Study; MUSC POSITIVE Trial; Penumbra 3D Separator Trial, COMPASS Trial, INVEST Trial, MIVI Neuroscience EVAQ Trial; Rapid Medical SUCCESS Trial; InspireMD C-GUARDIANS IDE Pivotal Trial; stock or stock options in Adona Medical, Amnis Therapeutics, Bend IT Technologies, BlinkTBI, Buffalo Technology Partners, Cardinal Consultants, Cerebrotech Medical Systems, Cerevatech Medical, Cognition Medical, CVAID, E8, EndoStream Medical, Imperative Care, Instylla, International Medical Distribution Partners, Launch NY, NeuroRadial Technologies, Neurotechnology Investors, Neurovascular Diagnostics, Perflow Medical, Q’Apel Medical, QAS.ai, Radical Catheter Technologies, Rebound Therapeutics (purchased in 2019 by Integra Lifesciences), Rist Neurovascular (purchased in 2020 by Medtronic), Sense Diagnostics, Serenity Medical, Silk Road Medical, Songbird Therapy, Spinnaker Medical, StimMed, Synchron, Three Rivers Medical, Truvic Medical, Tulavi Therapeutics, Vastrax, VICIS, and Viseon AFD: Consulting fees from Cerenovus, Penumbra, Medtronic, Stryker, Oculus, and Koswire. No relevant relationships RD: No relevant relationships PK: No relevant relationships. VK: No relevant relationships. PL: No relevant relationships SB: No relevant relationships CJS: Participation on the data safety monitoring board or advisory board for Zoll Circulation JK: No relevant relationships PJ: No relevant relationships ST: No relevant relationships FC: No relevant relationships NL: Honoraria for lectures from Cerenovus, Stryker, and CrossMed. MAA: Funding to institution from MicroVention for WEBIT trial; proctoring fees from MicroVention. HHC: No relevant relationships CC: Consulting fees from MicroVention, Stryker, Medtronic, MIVI, and Cerenovus. ABP: Grant to institution from Medtronic; consulting fees from MicroVention, Medtronic, and Q’Apel; workstation for research from Siemens AAD: No relevant relationships, (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Endovascular thrombectomy (EVT) is the standard-of-care for proximal large vessel occlusion (LVO) stroke. Data on technical and clinical outcomes in distal vessel occlusions (DVOs) remain limited., Methods: This was a retrospective study of patients undergoing EVT for stroke at 32 international centers. Patients were divided into LVOs (internal carotid artery/M1/vertebrobasilar), medium vessel occlusions (M2/A1/P1) and isolated DVOs (M3/M4/A2/A3/P2/P3) and categorized by thrombectomy technique. Primary outcome was a good functional outcome (modified Rankin Scale ≤2) at 90 days. Secondary outcomes included recanalization, procedure-time, thrombectomy attempts, hemorrhage, and mortality. Multivariate logistic regressions were used to evaluate the impact of technical variables. Propensity score matching was used to compare outcome in patients with DVO treated with aspiration versus stent retriever RESULTS: We included 7477 patients including 213 DVOs. Distal location did not independently predict good functional outcome at 90 days compared with proximal (p=0.467). In distal occlusions, successful recanalization was an independent predictor of good outcome (adjusted odds ratio (aOR) 5.11, p<0.05) irrespective of technique. Younger age, bridging therapy, and lower admission National Institutes of Health Stroke Scale (NIHSS) were also predictors of good outcome. Procedure time ≤1 hour or ≤3 thrombectomy attempts were independent predictors of good outcomes in DVOs irrespective of technique (aOR 4.5 and 2.3, respectively, p<0.05). There were no differences in outcomes in a DVO matched cohort of aspiration versus stent retriever. Rates of hemorrhage and good outcome showed an exponential relationship to procedural metrics, and were more dependent on time in the aspiration group and attempts in the stent retriever group., Conclusions: Outcomes following EVT for DVO are comparable to LVO with similar results between techniques. Techniques may exhibit different futility metrics; stent retriever thrombectomy was influenced by attempts whereas aspiration was more dependent on procedure time., Competing Interests: Competing interests: AMA: None, RMC: None, SAK: Grant Funding-Stryker; PJ: Consultant-Balt, Cerus, Microvention, Medtronic. M-NP Honoraria - Stryker, Medtronic, Penumbra, Acandis, Phenox, Siemens Healthineers, Research Support-Swiss National Science Foundation, Bangerter-Rhyner Stiftung, Stryker, Phenox, Medtronic, Rapid, Penumbra, Siemens Healthineers; RMS: None; ASA: Consultant for Arsenal, Balt, Johnson and Johnson, Medtronic, Microvention, Penumbra, Scientia, Siemens, Stryker, Research support from Balt, Medtronic, Microvention, Penumbra and Siemens, Shareholder-Azimuth, Bendit, Cerebrotech, Endostream, Magneto, Mentice, Neurogami, Neuros, Scientia, Serenity, Synchron, Tulavi, Vastrax, VizAI; KMF: Editorial Board-JNIS; RDL: Consultant-Stryker, Imperative Care, Cerenovus, Asahi Intec, Research Funding-Hypervention, Kaneka, Siemens Healthineers, SNIS Foundation, Equity-Synchron, Endostream, Q’Apel, Spartan Micro, Editorial Board-JNIS; PK: Consultant- Stryker, Imperative Care, Microvention, Grant Support-NIH, Editorial-Board JNIS; TD: None; AR: None; RJC: None; IM: None; NG: None; SQW: Board of Directors-AANS, Associate Editor- S:VIN Journal; CMC: None; JM: PI on trials funded by- Stryker Neurovascular, Microvention, and Penumbra, Consultant-Cerebrotech, Viseon, Endostream, Vastrax, RIST, Synchron, Viz.ai, Perflow, CVAid, Stockholder-Cerebrotech, Imperative Care, Endostream, Viseon, BlinkTBI, Myra Medical, Serenity, Vastrax, NTI, RIST, Viz.ai, Synchron, Radical, and Truvic; Editorial Board-JNIS; SIT: Consultant- Microvention, Medtronic; BMH: None; LD: None; HS: None; CSO: Grant Support- Bee Foundation, Brain Aneurysm Foundation, DSMB- Medtronic; RWC: Consultant/Proctor: Medtronic, Microvention; JMa: consultant-Stryker; IF: None; MRL: Educational Grant-Stryker, Medtronic, Consultant-Medtronic, Aeaean Advisers, Travel Support-Penumbra, Editorial Board, JNIS, Stock- Hyperion Surgical, Proprio, Synchron, Cerebrotech, Fluid Biomed, Stereotaxis, Advisor-Metis Innovative; J-tK: None; MSP: DSMB-Medtronic; BG: None; AJP: Consultant-Depuy Synthes, Stryker, CM: Consultant-Silk Road, Penumbra, Microvention, Cerevasc, Stryker, Speaker-Silk Road, Penumbra; JAG: Grant Support- Georgia Research Alliance, Department of Defense, Emory Medical Care Foundation, Neurosurgery Catalyst, Stock- NTI, Cognition; AMS: Consultant- Stryker, Penumbra, Terumo, RapidAI; STAR: funded by Penumbra, Medtronic, Stryker., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Several studies have shown promising outcomes of the Woven EndoBridge (WEB) device for the treatment of wide-necked intracranial bifurcation aneurysms. This is a multicenter study attempts to explore the changes in trends and treatment outcomes over time for WEB embolization of intracranial aneurysms. The WorldWideWEB consortium is a retrospective multicenter collaboration of data from international centers spanning from January 2011 and June 2021, with no limitations on aneurysm location or rupture status. Both bifurcation and sidewall aneurysms were included. These patients were stratified based on treatment year into five treatment intervals: 2011-2015 (N = 66), 2016-2017 (N = 77), 2018 (N = 66), 2019 (N = 300), and 2020-2021 (N = 173). Patient characteristics and angiographic and clinical outcomes were compared between these time intervals. This study comprised 671 patients (median age 61.4 years; 71.2% female) with 682 intracranial aneurysms. Over time, we observed an increasing tendency to treat patients presenting with ruptured aneurysms and aneurysms with smaller neck, diameter, and dome widths. Furthermore, we observed a trend towards more off-label use of the WEB for sidewall aneurysms and increased adoption of transradial access for WEB deployment. Moreover, the proportion of patients with adequate WEB occlusion immediately and at last follow-up was significantly higher in more recent year cohorts, as well as lower rates of compaction and retreatment. Mortality and complications did not differ over time. This learning curve study suggests improved experience using the WEB for the treatment of intracranial aneurysms and has yielded higher rates of adequate occlusion over time., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: The Surpass flow diverter was developed to treat intracranial aneurysms not amenable to standard treatment. Indications for use allow placement in the internal carotid artery to the terminus, including the communicating artery segment., Methods: The Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Wide Neck Aneurysms (SCENT) trial is an international, multicenter, prospective, non-randomized trial comparing the outcomes of Surpass flow diverter treatment with historic control designed to evaluate the effectiveness and safety of Surpass for the treatment of wide neck (≥4 mm) large or giant intracranial aneurysms ≥10 mm. The primary effectiveness endpoint is the percentage of subjects with 100% aneurysm occlusion without significant stenosis of the parent artery and without retreatment of the target aneurysm at 12 months. The primary safety endpoint is the percentage of subjects experiencing neurologic death or major ipsilateral stroke at 12 months. We report the effectiveness and safety of flow diversion in the subgroup of posterior communicating artery (PComA) aneurysms., Results: Of the 180 patients treated, 38 harbored a PComA aneurysm. Mean aneurysm size was 12.2 mm and mean neck width was 4.8 mm. The mean number of Surpass devices used was 1.1 per procedure, with 94.7% of aneurysms treated with one flow diverter. The 12 month primary effectiveness rate was 73.7% (28/38). At 36 months, 68.4% (26/38) of aneurysms remained completely occluded. The 12 month major ipsilateral stroke or neurological death rate was 10.5%. No patients with PComA occlusion after flow diverter placement (54.5%) had clinical sequelae., Conclusions: SCENT demonstrated acceptable 12 month effectiveness of flow diversion in PComA aneurysms. Despite associated PComA occlusions in many cases, arterial occlusions were clinically silent., Trial Registration Number: URL: https://www., Clinicaltrials: gov. Unique identifier: NCT01716117., Competing Interests: Competing interests: PK: consultant for Stryker and Cerenovus, and stockholder of InNeuroCo; editorial board member of Journal of NeuroInterventional Surgery; and education chair of the Society of NeuroInterventional Surgery. PMM: consultant for Stryker, Medtronic, and Penumbra. ALC: consultant for Stryker, Medtronic, Microvention, and InNeuroCo. AKW: research grant from Philips Medical; serves as a consultant for Stryker; is a stockholder of InNeuroCo, NovaSignal, Rist, Analytics 4 Life, and ThrombX; and is on the speakers’ bureau for the SCENT trial (Surpass Intracranial Aneurysm Embolization System Pivotal Trial to Treat Large or Giant Wide Neck Aneurysms) presentations. JD: consultant for Stryker and Evasc. KE: consultant for Stryker and Microvention. RAH: research grant from Medtronic, Stryker, Microvention, and Cerenovus; consultant for Stryker, Medtronic, Cerenovus, and Microvention; stockholder in Neurvana, Elum, EndoStream, Three Rivers Medical Inc, Rist, Cerebrotech, and InNeuroCo; scientific advisor for MIVI, Elum, Three Rivers Medical Inc, and Shape Medical. PT: consultant for Medtronic, Cerenovus, and Stryker., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The Woven EndoBridge (WEB) device has Food and Drug Administration approval for treatment of wide-necked intracranial bifurcation aneurysms. The WEB device has been shown to result in adequate occlusion in bifurcation aneurysms overall, but its usefulness in the individual bifurcation locations has been evaluated separately only in few case series, which were limited by small sample sizes., Objective: To compare angiographic and clinical outcomes after treatment of bifurcation aneurysms at various locations, including anterior communicating artery (AComA), anterior cerebral artery (ACA) bifurcation distal to AComA, basilar tip, internal carotid artery (ICA) bifurcation, and middle cerebral artery (MCA) bifurcation aneurysms using the WEB device., Methods: A retrospective cohort analysis was conducted at 22 academic institutions worldwide to compare treatment outcomes of patients with intracranial bifurcation aneurysms using the WEB device. Data include patient and aneurysm characteristics, procedural details, angiographic and functional outcomes, and complications., Results: A total of 572 aneurysms were included. MCA (36%), AComA (35.7%), and basilar tip (18.9%) aneurysms were most common. The rate of adequate aneurysm occlusion was significantly higher for basilar tip (91.6%) and ICA bifurcation (96.7%) aneurysms and lower for ACA bifurcation (71.4%) and AComA (80.6%) aneurysms (p=0.04)., Conclusion: To our knowledge, this is the most extensive study to date that compares the treatment of different intracranial bifurcation aneurysms using the WEB device. Basilar tip and ICA bifurcation aneurysms showed significantly higher rates of aneurysm occlusion than other locations., Competing Interests: Competing interests: The following authors serve on the editorial board of JNIS, JDBD, AG, AFD, FCA, and PK., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: With the development of advanced endovascular techniques and materials, neurointerventionalists can perform challenging and complex cases that were previously difficult to perform. Transcirculation approaches could be a useful tool used in complicated cases, providing access to the target vessel, through the contralateral or opposite circulation, when anterograde access is difficult or nonachievable., Objective: To retrospectively review cerebrovascular interventions performed through a transcirculation approach performed by staff at our Institution., Methods: English-language studies, published until August 2022, reporting transcirculation interventions in the cerebrovascular circulation were retrospectively collected. Type of intervention, number of cases, rationale, and complications were analyzed. Furthermore, similar cases performed by staff currently at our institution were also reviewed and described., Results: Including our cases, a total of 273 transcirculation treatment approaches have been reported. Intracranial aneurysm embolization, stroke thrombectomies, intra-arterial ophthalmic chemotherapy, arteriovenous malformationss, arteriovenous fistulas embolizations, and intracranial angioplasty and stenting are common indications. Reason for using a retrograde approach were stent/balloon-assisted coiling of wide neck aneurysm in 116 cases, difficult angulation of branch in 91 cases, occlusion of parent vessel in 55 cases, and bailout/other in 11 cases., Conclusion: Transcirculation approaches can be considered for cases where conventional anterograde treatment options are not feasible or as a bailout strategy in failed or complicated treatment attempts. They represent a strategy to consider when facing challenging cases, and if performed by experienced and dedicated neurointerventionalists, they can represent a safe alternative., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Objective: The role of endovascular mechanical thrombectomy (MT) in patients presenting with "minor" stroke is uncertain. We aimed to compare outcomes after MT for ischemic stroke patients presenting with National Institutes of Health Stroke Scale (NIHSS) 5 and - within the low NIHSS cohort - identify predictors of a favorable outcome, mortality, and symptomatic intracranial hemorrhage (ICH)., Methods: We retrospectively analyzed a prospectively maintained, international, multicenter database., Results: The study cohort comprised a total of 7568 patients from 29 centers. NIHSS was low (<5) in 604 patients (8%), and > 5 in 6964 (92%). Patients with low NIHSS were younger (67 + 14.8 versus 69.6 + 14.7 years, p < 0.001), more likely to have diabetes (31.5% versus 26.9%, p = 0.016), and less likely to have atrial fibrillation (26.6% versus 37.6%, p < 0.001) compared to those with higher NIHSS. Radiographic outcomes (TICI > 2B 84.6% and 84.3%, p = 0.412) and complication rates (8.1% and 7.2%, p = 0.463) were similar between the low and high NIHSS groups, respectively. Clinical outcomes at every follow up interval, including NIHSS at 24 h and discharge, and mRS at discharge and 90 days, were better in the low NIHSS group, however patients in the low NIHSS group experienced a relative decline in NIHSS from admit to discharge. Mortality was lower in the low NIHSS group (10.4% versus 24.5%, p < 0.001)., Conclusions: Relative to patients with high NIHSS, MT is safe and effective for stroke patients with low NIHSS, and it is reasonable to offer it to appropriately selected patients presenting with minor stroke symptoms. Our findings justify efforts towards a randomized trial comparing MT versus medical management for patients with low NIHSS., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Background: Parenchymal hemorrhage (PH) is a troublesome complication after endovascular treatment (EVT)., Objective: To investigate the incidence, independent predictors, and clinical impact of PH after EVT in patients with acute ischemic stroke (AIS) due to anterior circulation large vessel occlusion (LVO)., Methods: Subjects were selected from the ANGEL-ACT Registry. PH was diagnosed according to the European Collaborative Acute Stroke Study classification. Logistic regression analyses were performed to determine the independent predictors of PH, as well as the association between PH and 90-day functional outcome assessed by modified Rankin Scale (mRS) score., Results: Of the 1227 enrolled patients, 147 (12.0%) were diagnosed with PH within 12-36 hours after EVT. On multivariable analysis, low admission Alberta Stroke Program Early CT score (ASPECTS)(adjusted OR (aOR)=1.13, 95% CI 1.02 to 1.26, p=0.020), serum glucose >7 mmol/L (aOR=1.82, 95% CI 1.16 to 2.84, p=0.009), and neutrophil-to-lymphocyte ratio (NLR; aOR=1.05, 95% CI 1.02 to 1.09, p=0.005) were associated with a high risk of PH, while underlying intracranial atherosclerotic stenosis (ICAS; aOR=0.42, 95% CI 0.22 to 0.81, p=0.009) and intracranial angioplasty/stenting (aOR=0.37, 95% CI 0.15 to 0.93, p=0.035) were associated with a low risk of PH. Furthermore, patients with PH were associated with a shift towards to worse functional outcome (mRS score 4 vs 3, adjusted common OR (acOR)=2.27, 95% CI 1.53 to 3.38, p<0.001)., Conclusions: In Chinese patients with AIS caused by anterior circulation LVO, the risk of PH was positively associated with low admission ASPECTS, serum glucose >7 mmol/L, and NLR, but negatively related to underlying ICAS and intracranial angioplasty/stenting., Trial Registration Number: NCT03370939., Competing Interests: Competing interests: ZR: consultant to Penumbra Company, USA., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Data regarding the safety and efficacy of flow diverting stents (FDS) in the treatment of middle cerebral artery (MCA) bifurcation aneurysms are scarce and limited to small single center series, with particular concern for increased risk of ischemic complications with jailing one of the M2 branches., Methods: Prospectively-maintained databases at six North American and European centers were queried for patients harboring MCA bifurcation aneurysms undergoing treatment with FDS (2011-2018). The pertinent clinical and radiographic data were collected and analyzed., Results: 87 patients (median age 60 years, 69% females) harboring 87 aneurysms were included. The majority of aneurysms were unruptured (79%); 75.9% were saccular with a median maximal diameter of 8.5 mm. Radiographic imaging follow-up was available in 88.5% of cases at a median of 16.3 months post-treatment, showing complete occlusion in 59% and near complete occlusion (90-99%) in 18% of aneurysms. The overall rate of ischemic and hemorrhagic complications was 8% and 1.1%, respectively. Symptomatic and permanent complications were encountered in 5.7% and 2.3% of patients respectively, with retreatment pursued in 2.3% of patients. Jailed branch occlusion was detected in 11.5% of cases, with clinical sequelae in 2.3%. Last follow-up modified Rankin Scale of 0-2 was noted in 96.8% of patients. On multivariate analysis, male sex was the only independent predictor of aneurysmal persistence at last follow-up imaging (p=0.019)., Conclusion: FDS treatment for MCA bifurcation aneurysms is feasible, with comparable safety and efficacy profiles to other available endovascular options when utilized in carefully selected aneurysms. Jailing of M2 branches was not associated with a higher risk of post-procedural ischemic complications., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose: Previous studies suggest that mechanisms and outcomes in patients with COVID-19-associated stroke differ from those in patients with non-COVID-19-associated strokes, but there is limited comparative evidence focusing on these populations. The aim of this study, therefore, was to determine if a significant association exists between COVID-19 status with revascularization and functional outcomes following thrombectomy for large vessel occlusion (LVO), after adjustment for potential confounding factors., Methods: A cross-sectional, international multicenter retrospective study was conducted in consecutively admitted COVID-19 patients with concomitant acute LVO, compared to a control group without COVID-19. Data collected included age, gender, comorbidities, clinical characteristics, details of the involved vessels, procedural technique, and various outcomes. A multivariable-adjusted analysis was conducted., Results: In this cohort of 697 patients with acute LVO, 302 had COVID-19 while 395 patients did not. There was a significant difference (p &lt; 0.001) in the mean age (in years) and gender of patients, with younger patients and more males in the COVID-19 group. In terms of favorable revascularization (modified Thrombolysis in Cerebral Infarction [mTICI] grade 3), COVID-19 was associated with lower odds of complete revascularization (odds ratio 0.33, 95% confidence interval [CI] 0.23-0.48; p &lt; 0.001), which persisted on multivariable modeling with adjustment for other predictors (adjusted odds ratio 0.30, 95% CI 0.12-0.77; p = 0.012). Moreover, endovascular complications, in-hospital mortality, and length of hospital stay were significantly higher among COVID-19 patients (p &lt; 0.001)., Conclusion: COVID-19 was an independent predictor of incomplete revascularization and poor functional outcome in patients with stroke due to LVO. Furthermore, COVID-19 patients with LVO were more often younger and had higher morbidity/mortality rates., (© 2022 European Academy of Neurology.)

Background: The Pipeline Embolization Device (PED) has been the only flow-diverting device (FDD) approved by the Food and Drug Administration (FDA) in the U.S. market for nearly a decade, with more FDD choices in the United States following recent FDA approval of the Flow Redirection Endoluminal Device and Surpass. We sought to explore the integration patterns of these devices into practice by U.S. neurointerventionalists., Methods: A 34-question electronic survey was distributed to the U.S. neurointerventional community from different backgrounds (neurosurgery, neurology, radiology) through different organizational links, focusing on technical aspects of device selection and personal preferences/experiences regarding FDD in aneurysms treatment., Results: Responses were collected from 120 neurointerventionalists across the United States; operators from a neurosurgery background constituted the majority of respondents (47.5%; 85% of dual-trained). The largest age block was early-to mid-career operators (70.8% aged 36-50 years). Most participants (78.8%) treated a range of 25-100 aneurysms/year with FDDs, with 49.2% of respondents having all the FDA-approved FDDs available in their centers (80.8% academic practice). Femoral access was used by the 67.7% of respondents, without impact of FDD-device on access-type (89.2%). PED was the most commonly used device (70.9%), with 66.7% of respondents reporting using different FDD based on case specifics. Comparing devices preferences by training backgrounds, more neurosurgical operators endorsed PED as their most commonly used device, whereas more interventional neuroradiologists/neurologists reported Surpass and Flow Redirection Endoluminal Device as their most commonly used devices., Conclusions: The results of this survey identify common themes in FDD choices among neurointerventionalists in the U.S. market, along with their integration patterns of the newly introduced devices into clinical practice., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: Treatment of small-caliber vessel lesions using flow diverters remains challenging because of vasculature's narrow luminal diameter and tortuosity. This in turn makes navigation and delivery of conventional devices with standard microcatheters more difficult. The Silk Vista Baby (SVB, Balt) flow diversion device was designed for ease of use in vessels with a smaller diameter, distal lesions, and 0.017 ″ microcatheter delivery systems., Objective: To report the outcomes of the SVB device on the treatment of posterior inferior cerebellar artery (PICA) aneurysms., Methods: Databases from different centers were retrospectively reviewed for PICA aneurysms treated with SVB. Demographic information, clinical presentation, radiographic characteristics, procedural complications, and immediate postprocedure outcomes were obtained., Results: Fourteen patients harboring 15 true PICA aneurysms were treated between January 2019 and June 2021. Nine were female (n = 9/14; 64.2%), and the mean age was 51 ± 14.9 years. Most patients had previously ruptured aneurysms, treated by another endovascular technique. Six aneurysms were located distally (n = 6/15; 40%). The mean neck size was 3 mm (SD 1.35, range 2.5-5 mm), whereas the mean PICA diameter was 1.6 mm (SD 0.26, range 1.5-1.7 mm). The mean length of follow-up was 6 months (SD 8.28, range 4.5-16 months). Treatment-related adverse events included 1 case of transient hypoesthesia. Two additional events were reported, but adjudicated as unrelated to the procedure. Complete occlusion, measured as Raymond-Roy class I, was achieved in all cases., Conclusion: The SVB device was safely and effectively used in the treatment of PICA aneurysms. The smaller delivery system profile reduces the risk of procedure complications and creates new treatment options for distal lesions., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Background The Woven EndoBridge (WEB) device was explicitly designed for wide-neck intracranial bifurcation aneurysms. Small-scale reports have evaluated the off-label use of WEB devices for the treatment of sidewall aneurysms, with promising outcomes. Purpose To compare the angiographic and clinical outcomes of the WEB device for the treatment of sidewall aneurysms compared with the treatment of bifurcation aneurysms. Materials and Methods A retrospective review of the WorldWideWEB Consortium, a synthesis of retrospective databases spanning from January 2011 to June 2021 at 22 academic institutions in North America, South America, and Europe, was performed to identify patients with intracranial aneurysms treated with the WEB device. Characteristics and outcomes were compared between bifurcation and sidewall aneurysms. Propensity score matching (PSM) was used to match by age, pretreatment ordinal modified Rankin Scale score, ruptured aneurysms, location of aneurysm, multiple aneurysms, prior treatment, neck, height, dome width, daughter sac, and incorporated branch. Results A total of 683 intracranial aneurysms were treated using the WEB device in 671 patients (median age, 61 years [IQR, 53-68 years]; male-to-female ratio, 1:2.5). Of those, 572 were bifurcation aneurysms and 111 were sidewall aneurysms. PSM was performed, resulting in 91 bifurcation and sidewall aneurysms pairs. No significant difference was observed in occlusion status at last follow-up, deployment success, or complication rates between the two groups. Conclusion No significantly different outcomes were observed following the off-label use of the Woven EndoBridge, or WEB, device for treatment of sidewall aneurysms compared with bifurcation aneurysms. The correct characterization of the sidewall aneurysm location, neck angle, and size is crucial for successful treatment and lower retreatment rate. © RSNA, 2022 See also the editorial by Hetts in this issue.

Background: The Woven EndoBridge (WEB) device (Terumno Corp. [parent company of Microvention]) was approved by the U.S. Food and Drug Administration as the first intrasaccular device for intracranial aneurysm treatment in December 2018. Its use has become more common since then, but both trial results and postmarket experiences have raised questions about the efficacy in achieving complete aneurysm obliteration. Retreatment after WEB embolization has not been extensively discussed., Objective: To discuss the incidence and retreatment of aneurysms after initial WEB embolization., Methods: Retrospective review across 13 institutions identified all occurrences of WEB retreatment within neurovascular databases. Details regarding demographics, aneurysm characteristics, treatment considerations, clinical outcomes, and aneurysm occlusion were obtained and analyzed., Results: Thirty aneurysms were retreated in 30 patients in a cohort of 342 WEB-treated aneurysms. The retreatment rate was 8.8%. Endovascular methods were used for 23 cases, and 7 were treated surgically. Two aneurysms presented with rehemorrhage after initial WEB embolization. Endovascular treatments included stent-assisted coiling (12), flow diversion (7), coiling (2), PulseRider (Johnson & Johnson)-assisted coiling (1), and additional WEB placement (1). Surgical treatments included primary clipping (6) and Hunterian ligation (1). There were no major complications within the study group., Conclusion: WEB retreatments were successfully performed by a variety of techniques, including stent-assisted coiling, clipping, and flow diversion as the most common. These procedures were performed safely with subsequent obliteration of most aneurysms. The potential need for retreatment of aneurysms should be considered during primary WEB treatments., (Copyright © Congress of Neurological Surgeons 2022. All rights reserved.)

Background: Aneurysmal persistence after flow diversion (FD) occurs in 5% to 25% of aneurysms, which may necessitate retreatment. There are limited data on safety/efficacy of repeat FD-a frequently utilized strategy in such cases., Methods: A series of consecutive patients undergoing FD retreatment from 15 centers were reviewed (2011-2019), with inclusion criteria of repeat FD for the same aneurysm at least 6 months after initial treatment, with minimum of 6 months post-retreatment imaging. The primary outcome was aneurysmal occlusion, and secondary outcome was safety. A multivariable logistic regression model was constructed to identify predictors of incomplete occlusion (90%-99% and <90% occlusion) versus complete occlusion (100%) after retreatment., Results: Ninety-five patients (median age, 57 years; 81% women) harboring 95 aneurysms underwent 198 treatment procedures. Majority of aneurysms were unruptured (87.4%), saccular (74.7%), and located in the internal carotid artery (79%; median size, 9 mm). Median elapsed time between the first and second treatment was 12.2 months. Last available follow-up was at median 12.8 months after retreatment, and median 30.6 months after the initial treatment, showing complete occlusion in 46.2% and near-complete occlusion (90%-99%) in 20.4% of aneurysms. There was no difference in ischemic complications following initial treatment and retreatment (4.2% versus 4.2%; P >0.99). On multivariable regression, fusiform morphology had higher nonocclusion odds after retreatment (odds ratio [OR], 7.2 [95% CI, 1.97-20.8]). Family history of aneurysms was associated with lower odds of nonocclusion (OR, 0.18 [95% CI, 0.04-0.78]). Likewise, positive smoking history was associated with lower odds of nonocclusion (OR, 0.29 [95% CI, 0.1-0.86]). History of hypertension trended toward incomplete occlusion (OR, 3.10 [95% CI, 0.98-6.3]), similar to incorporated branch into aneurysms (OR, 2.78 [95% CI, 0.98-6.8])., Conclusions: Repeat FD for persistent aneurysms carries a reasonable success/safety profile. Satisfactory occlusion (100% and 90%-99% occlusion) was encountered in two-thirds of patients, with similar complications between the initial and subsequent retreatments. Fusiform morphology was the strongest predictor of retreatment failure.

Background: Elevated blood pressure after endovascular thrombectomy (EVT) has been associated with an increased risk of hemorrhagic transformation and poor functional outcomes. However, the optimal hemodynamic management after EVT remains unknown, and the blood pressure course in the acute phase of ischemic stroke has not been well characterized. This study aimed to identify patient subgroups with distinct blood pressure trajectories after EVT and study their association with radiographic and functional outcomes., Methods: This multicenter retrospective cohort study included consecutive patients with anterior circulation large-vessel occlusion ischemic stroke who underwent EVT. Repeated time-stamped blood pressure data were recorded for the first 72 hours after thrombectomy. Latent variable mixture modeling was used to separate subjects into five groups with distinct postprocedural systolic blood pressure (SBP) trajectories. The primary outcome was functional status, measured on the modified Rankin Scale 90 days after stroke. Secondary outcomes included hemorrhagic transformation, symptomatic intracranial hemorrhage, and death., Results: Two thousand two hundred sixty-eight patients (mean age [±SD] 69±15, mean National Institutes of Health Stroke Scale 15±7) were included in the analysis. Five distinct SBP trajectories were observed: low (18%), moderate (37%), moderate-to-high (20%), high-to-moderate (18%), and high (6%). SBP trajectory group was independently associated with functional outcome at 90 days ( P <0.0001) after adjusting for potential confounders. Patients with high and high-to-moderate SBP trajectories had significantly greater odds of an unfavorable outcome (adjusted odds ratio, 3.5 [95% CI, 1.8-6.7], P =0.0003 and adjusted odds ratio, 2.2 [95% CI, 1.5-3.2], P <0.0001, respectively). Subjects in the high-to-moderate group had an increased risk of symptomatic intracranial hemorrhage (adjusted odds ratio, 1.82 [95% CI, 1-3.2]; P =0.04). No significant association was found between trajectory group and hemorrhagic transformation., Conclusions: Patients with acute ischemic stroke demonstrate distinct SBP trajectories during the first 72 hours after EVT that have differing associations with functional outcome. These findings may help identify potential candidates for future blood pressure modulation trials.

Background: Open surgery has traditionally been preferred for the management of bifurcation middle cerebral artery (MCA) aneurysms. Flow diverting stents present a novel endovascular strategy for aneurysm treatment., Objective: To add to the limited literature describing the outcomes and complications in the use of flow diverters for the treatment of these complex aneurysms., Methods: This is a multicenter retrospective review of MCA bifurcation aneurysms undergoing flow diversion. We assessed post-treatment radiological outcomes and both thromboembolic and hemorrhagic complications., Results: We reviewed the outcomes of 54 aneurysms treated with flow diversion. Four (7.4%) of the aneurysms had a history of rupture (3 remote and 1 acute). Fourteen (25.9%) of the aneurysms already underwent either open surgery or coiling prior to flow diversion. A total of 36 out of the 45 aneurysms (80%) with available follow-up data had adequate aneurysm occlusion with a median follow-up time of 12 mo. There were no hemorrhagic complications but 16.7% (9/54) had thromboembolic complications., Conclusion: Flow diverting stents may be a viable option for the endovascular treatment of complex bifurcation MCA aneurysms. However, compared to published series on the open surgical treatment of this subset of aneurysms, flow diversion has inferior outcomes and are associated with a higher rate of complications., (© Congress of Neurological Surgeons 2021.)

Objective: Blood blister aneurysms are small, thin-walled, rapidly growing side-wall aneurysms that have proved particularly difficult to treat, and evidence-based guidance for treatment strategies is lacking. A systematic review and meta-analysis was performed to aggregate the available data and compare the 3 primary treatment modalities., Methods: We performed a comprehensive literature search according to PRISMA guidelines followed by an indirect meta-analysis that compares the safety and efficacy of surgical, flow-diverting stents (FDS), and other endovascular approaches for the treatment of ruptured blood blister aneurysms., Results: A total of 102 studies were included for quantitative synthesis, with sample sizes of 687 treated surgically, 704 treated endovascularly without FDS, and 125 treated via flow diversion. Comparatively, FDS achieved significantly reduced rates of perioperative retreatment compared with both surgical (P = 0.025) and non-FDS endovascular (P < 0.001). The FDS subgroup also achieved a significantly lower incidence of perioperative rebleed (P < 0.001), perioperative hydrocephalus (P = 0.012), postoperative infarction (P = 0.002), postoperative hydrocephalus (P < 0.001), and postoperative vasospasm (P = 0.002) compared with those patients in the open surgical subgroup. Although no significant differences were found among groups on the basis of functional outcomes, angiographic outcomes detailed by rates of radiographic complete occlusion were highest for surgical (90.7%, 262/289) and FDS (89.1%, 98/110) subgroups versus the non-FDS endovascular subgroup (82.7%, 268/324)., Conclusions: Flow diversion seems to be an effective treatment strategy for ruptured blood blister aneurysms, with lower rates of perioperative complications compared with surgical and other endovascular techniques, but studies investigating long-term outcomes after flow diversion warrant further study., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: The off-hour effect has been observed in the medical care of acute ischemic stroke. However, it remains unclear if time of arrival affects revascularization rates and outcomes after endovascular therapy (EVT) for emergent large vessel occlusion (ELVO). We aimed to investigate the clinical outcomes of EVT between on-hour and off-hour admissions., Methods: Patients who underwent EVT for ELVO from January 2013 to June 2019 from the STAR Registry were included. Patients were grouped based on time of groin puncture: on-hour period (Monday through Friday, 7:00 am-4:59 pm) and off-hour period (overnight 5:00pm-6:59am and the weekends). Primary outcome was final modified Rankin Scale (mRS) at 90 days on mRS-shift analysis., Results: A total of 1919 patients were included in the study from six centers. The majority of patients (1169, 60.9%) of patients presented during the off-hour period. The mean age was 68.1 years and 50.5% were women. Successful reperfusion, as defined by a Thrombolysis In Cerebral Infarction (TICI) score of ≥2B, was achieved in 88.8% in the on-hour group and 88.0% in the off-hour group. Good clinical outcome (mRS 0-2) was obtained in 34.4% of off-hour patients and 37.7% of on-hour patients. On multivariable ordinal logistic regression analysis, time of presentation was not associated with worsened outcome (OR 1.150; 95% CI 0.96 to 1.37; P=0.122). Age, admission National Institutes of Health Stroke Scale (NIHSS), baseline mRS, and final TICI score were significantly associated with worse outcomes., Conclusion: There is no statistical difference in functional outcome in acute ischemic stroke patients who underwent EVT during on-hours versus off-hours., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Cerebral venous sinus thrombosis (CVST) is a rare but potentially morbid disease in the pediatric population, and the optimal treatment is not fully understood. Endovascular intervention for this condition has been rarely reported., Methods: The Stroke Thrombectomy and Aneurysm Registry was queried for patients aged less than or equal to 18 years undergoing endovascular treatment for CVST in the past 10 years. Clinical charts and radiographic data were retrospectively reviewed. Modified Rankin Score (mRS) at 90 days postprocedure was determined as the primary outcome., Results: A total of seven patients across five pediatric centers ranging from 7 to 16 years of age were identified with a mean follow-up of 28 months. All had underlying conditions predisposing to CVST. Endovascular intervention was undertaken due to neurological deterioration despite systemic anticoagulation; venous infarct was evident preoperatively in six of seven patients. Mechanical venous thrombectomy was attempted in all individuals, and intrasinus thrombolytic therapy was also performed in three cases. Six patients had favorable outcome with mRS 0 or 1 at 90 days postprocedure; one remained neurologically devastated., Conclusions: Endovascular treatment by an experienced interventionalist may be safe and effective in severe cases of CVST in children failing frontline therapy. Children with radiographic or clinical progression despite anticoagulation may be considered for endovascular intervention in a timely manner., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: The Woven EndoBridge (WEB) device was granted premarket approval in the United States following results of the Woven EndoBridge Intrasaccular Therapy (WEB-IT) study. WEB-IT reported excellent adequate angiographic occlusion of treated aneurysms with a high safety profile. These results were achieved, however, in the context of a prospective study with strict inclusion criteria and rigorous training support., Objective: To review early as-practiced clinical experience with the WEB device in the United States., Methods: Retrospective review across 6 institutions identified 91 patients undergoing 92 treatment sessions for WEB device placement in treatment of 91 intracranial aneurysms. Details regarding demographics, aneurysm characteristics, treatment considerations, clinical outcomes, and aneurysm occlusion were obtained and analyzed in a multicenter database. Angiograms from the index procedure and follow-up studies were reviewed by a blinded and independent adjudicator., Results: The middle cerebral, anterior communicating, and basilar artery complexes were the commonly treated locations. Eight patients presented with ruptured aneurysms. A mean of 1.2 devices were introduced per case. Technical failure without deployment of a WEB device occurred in 2% (2/92) of sessions. Complete aneurysm occlusion for patients with imaging follow-up was 49% (mean follow-up of 8 mo). Four aneurysms were retreated. 90% of patients had modified Rankin Scale ≤ 2 at last clinical follow-up with no mortalities., Conclusion: Immediate postmarket experience with the WEB device, newly introduced at American centers, confirms safe procedural use, but long-term efficacy remains unclear. Early challenges include accurate sizing and device selection., (© Congress of Neurological Surgeons 2021.)

As capabilities for endovascular treatment of intracranial vascular pathologies continue to expand, the need for access to the distal internal carotid artery with rigid support catheter systems continues to increase. One of the dominant factors limiting this access is patient anatomy, specifically vessel tortuosity. Increased tortuosity of the carotid siphon is a frequently encountered anatomic variant and may complicate endovascular procedures in adults and children.1,2 Failed attempts to navigate the carotid siphon with a distal access catheter carry a risk of vessel injury and treatment failure. For this reason, techniques that aid in supporting safe advancement of a distal access catheter across a tortuous carotid siphon are essential.3,4 In this video, we demonstrate 2 ways in which this may be accomplished. The first technique uses a larger diameter microcatheter, such as the AXS Offset catheter (Stryker, Kalamazoo, Michigan), to increase support for the distal access catheter, while the second uses a buddy wire technique to accomplish this increased support. Both of these techniques can help increase the safety of navigating a tortuous carotid siphon and increase the likelihood of successful treatment.  The procedures shown were performed with the informed consent of the patients., (© Congress of Neurological Surgeons 2021.)

Background: We aimed to determine the effects of endovascular coiling of unruptured intracranial aneurysms (UIAs) on cognition to inform treatment decisions. We present the first study using the Montreal Cognitive Assessment (MoCA) to determine neurocognitive changes after endovascular coiling., Methods: We prospectively collected data on all patients with UIAs undergoing endovascular coiling, primary or assisted. Patients completed the MoCA prior to intervention and 1 month and 6 months' post-procedure. A repeated measures linear mixed effects model was used to compare pre-procedure and post-procedure cognition., Results: Thirty-three patients with 33 aneurysms who underwent coiling from April 2017 to May 2020 were included (mean age 55.5, 81.8% female). All procedures used general anesthesia. There was no difference between baseline and post-procedure MoCA scores at any time interval (P>0.05). Mean MoCA scores at baseline, 1 month post-procedure, and 6 months' post-procedure were 25.4, 26.8, and 26.3 respectively. There was also no difference between pre- and post-procedure scores on any individual MoCA domain (visuospatial, naming, memory, attention, language, abstraction, delayed recall, and orientation) at any time interval (P>0.05). Seventeen patients had follow-up MRI or CT imaging, of which 11.8% showed radiographic changes or ischemia. 77.8% of patients with 6-month angiographic follow-up achieved class I, and 22.2% achieved class II Raymond-Roy Occlusion. Thirty-two out of 33 patients had follow-up mRS ≤2., Conclusion: Our study suggests that endovascular coiling does not diminish neurocognitive function. Patients with UIAs in our cohort also had baseline MoCA scores below the cut-off for mild cognitive impairment despite pre-procedure mRS and NIHSS of 0., Competing Interests: Competing interests: PK: consultant for Cerenovus, Stryker., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Purpose: We report a multicenter experience using endovascular embolization as the first line approach for treatment of anterior cranial fossa (ACF) dural arteriovenous fistula (DAVF)., Methods: All patients with DAVFs located in the anterior cranial fossa who were treated with endovascular technique as a first line approach were included. Demographics, clinical presentation, angioarchitecture, strategy, complications, immediate angiographic, and follow-up results were included in the analysis., Results: Twenty-three patients met the inclusion criteria (18 male and 5 female). Age ranged from 14 to 79 years (mean 53 years). Twelve patients presented with hemorrhage. Twenty-eight endovascular procedures were performed. The overall immediate angiographic cure rate after endovascular treatment was 82.6% (19/23 patients). The angiographic cure rate of the transvenous strategy was significantly superior to the transarterial strategy (p ≤ 0.001). There was 1 complication in 28 total procedures (3.6%). Angiographic follow-up was available in 21 out of the 23 patients with a mean of 25 months (range 2 to 108 months). In these 21 patients, the DAVF was completely cured in 20 (95%). At last follow-up, all patients had a modified Rankin scale (mRS) 0 to 2., Conclusion: Our experience suggests that endovascular treatment for ACF DAVFs has an acceptable safety profile with high rates of complete occlusion, particularly with transvenous approach. Whenever possible, transvenous approach should be preferred over transarterial approach as first line strategy.

Emergent thrombectomy for large vessel occlusion is now a standard procedure within neurosurgery. In general, thrombectomy is attempted via a femoral artery puncture. However, due to anatomic variability and arterial tortuosity, target vessels cannot be catheterized in roughly 5% of patients.1 Radial artery access is an alternative to femoral artery access; however, target arteries for thrombectomy cannot be catheterized via the femoral or radial arteries in a small subset of patients. Direct carotid puncture is an alternative route of access for emergent thrombectomy in acute stroke.2,3 In this video, we present a patient with an acute right middle cerebral artery occlusion who was taken for emergent thrombectomy after consenting for the procedure. Because of unfavorable arterial anatomy, the right internal carotid artery could not be successfully catheterized via femoral or radial arterial punctures. We ultimately catheterized the right internal carotid artery and middle cerebral artery via a direct carotid puncture. We review the technique for direct carotid puncture, and discuss the outcomes associated with this method of access in the setting of acute large vessel occlusion. We also discuss complications associated with direct carotid puncture. Direct carotid puncture is an acceptable bail-out technique in the setting of emergent thrombectomy when femoral and/or radial access is not possible. Figure at 2:18 republished from Sekhar LN, Iwai Y, Wright DC, Bloom M. Vein graft replacement of the middle cerebral artery after unsuccessful embolectomy: case report. Neurosurgery. 1993;33(4):723-727, by permission of the Congress of Neurological Surgeons. Table at 6:05 modified from Roche A, Griffin E, Looby S, et al. Direct carotid puncture for endovascular thrombectomy in acute ischemic stroke. J NeuroIntervent Surg. 2019;11(7):647-652, ©The Authors, 2019, with permission from Dr Sarah Power. Table at 6:22 reproduced from Jadkhav AP, Ribo M, Grandhi R, et al. Transcervical access in acute ischemic stroke. J NeuroIntervent Surg. 2014:6(9):652-657, ©2013, with permission from the BMJ Publishing Group Ltd., (Copyright © 2021 by the Congress of Neurological Surgeons.)

Background: Middle meningeal artery (MMA) embolization has emerged as a promising treatment for chronic subdural hematoma (cSDH)., Objective: To determine the safety and efficacy of MMA embolization., Methods: Consecutive patients who underwent MMA embolization for cSDH (primary treatment or recurrence after conventional surgery) at 15 centers were included. Clinical details and follow-up were collected prospectively. Primary clinical and radiographic outcomes were the proportion of patients requiring additional surgical treatment within 90 d after index treatment and proportion with > 50% cSDH thickness reduction on follow-up computed tomography imaging within 90 d. National Institute of Health Stroke Scale and modified Rankin Scale were also clinical outcomes., Results: A total of 138 patients were included (mean age: 69.8, 29% female). A total of 15 patients underwent bilateral interventions for 154 total embolizations (66.7% primary treatment). At presentation, 30.4% and 23.9% of patients were on antiplatelet and anticoagulation therapy, respectively. Median admission cSDH thickness was 14 mm. A total of 46.1% of embolizations were performed under general anesthesia, and 97.4% of procedures were successfully completed. A total of 70.2% of embolizations used particles, and 25.3% used liquid embolics with no significant outcome difference between embolization materials (P > .05). On last follow-up (mean 94.9 d), median cSDH thickness was 4 mm (71% median thickness reduction). A total of 70.8% of patients had >50% improvement on imaging (31.9% improved clinically), and 9 patients (6.5%) required further cSDH treatment. There were 16 complications with 9 (6.5%) because of continued hematoma expansion. Mortality rate was 4.4%, mostly unrelated to the index procedure but because of underlying comorbidities., Conclusion: MMA embolization may provide a safe and efficacious minimally invasive alternative to conventional surgical techniques., (Copyright © 2020 by the Congress of Neurological Surgeons.)

Background: Currently, there are no large-scale studies in the neurointerventional literature comparing safety between transradial (TRA) and transfemoral (TFA) approaches for flow diversion procedures. This study aims to assess complication rates in a large multicenter registry for TRA versus TFA flow diversion., Methods: We retrospectively analyzed flow diversion cases for cerebral aneurysms from 14 institutions from 2010 to 2019. Pooled analysis of proportions was calculated using weighted analysis with 95% CI to account for results from multiple centers. Access site complication rate and overall complication rate were compared between the two approaches., Results: A total of 2,285 patients who underwent flow diversion were analyzed, with 134 (5.86%) treated with TRA and 2151 (94.14%) via TFA. The two groups shared similar patient and aneurysm characteristics. Crossover from TRA to TFA was documented in 12 (8.63%) patients. There were no access site complications in the TRA group. There was a significantly higher access site complication rate in the TFA cohort as compared with TRA (2.48%, 95% CI 2.40% to 2.57%, vs 0%; p=0.039). One death resulted from a femoral access site complication. The overall complications rate was also higher in the TFA group (9.02%, 95% CI 8.15% to 9.89%) compared with the TRA group (3.73%, 95% CI 3.13% to 4.28%; p=0.035)., Conclusion: TRA may be a safer approach for flow diversion to treat cerebral aneurysms at a wide range of locations. Both access site complication rate and overall complication rate were lower for TRA flow diversion compared with TFA in this large series., Competing Interests: Competing interests: RMS research is supported by the NREF, Joe Niekro Foundation, Brain Aneurysm Foundation, Bee Foundation, and by National Institute of Health (R01NS111119-01A1) and (UL1TR002736, KL2TR002737) through the Miami Clinical and Translational Science Institute, from the National Center for Advancing Translational Sciences and the National Institute on Minority Health and Health Disparities. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH. RMS has consulting and teaching agreements with Penumbra, Abbott, Medtronic, InNeuroCo and Cerenovus. DRY: Medtronic Neurovascular: Consultant, Cerenovus: Consultant, Rapid Medical and Neuralanalytics: consultant. ECP: Stryker Neurovascular: Consultant, Penumbra: Consultant, RIST Neurovascular: Stockholder, Medtronic Neurovascular: Consultant, Cerenovus: Consultant. MRL: Grants: National Institutes of Health (R01NS105692, R01NS088072, U24NS100654); American Heart Association (18CDA34110295); The Aneurysm and AVM Foundation. Unrestricted educational grants: Stryker Neurovascular, Medtronic, Philips Volcano. Equity interest: eLoupes Inc, Cerebrotech, Synchron. AS: Penumbra: consulting, research support, Stryker: consulting, Cerenovus: consulting. CMS: NTI stockholder, AANS honoraria. ASA: Consultant for Johnson and Johnson, Medtronic, Microvention, Penumbra, Scientia, Siemens, Stryker. Research support from Balt, Cerenovus, Medtronic, Microvention, Penumbra, Siemens, and Stryker. Shareholder in Bendit, Cerebrotech, Endostream, Magneto, Marblehead, Neurogami, Serenity, Synchron, Triad Medical, Vascular Simulations. JWO: Disclosures: consultant for Terumo, Medtronic, Microvention. Royalties: Caeli Vascular, inc., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Endovascular thrombectomy is a promising treatment for acute ischemic stroke in children, but outcome and technical data in pediatric patients with large-vessel occlusions are lacking., Objective: To assess technical and clinical outcomes of thrombectomy in pediatric patients., Methods: We undertook a retrospective cohort study of pediatric patients who experienced acute ischemic stroke from April 2017 to April 2019 who had immediate, 30-, and 90-d follow-up. Patients were treated with endovascular thrombectomy at 5 US pediatric tertiary care facilities. We recorded initial and postprocedural modified Thrombolysis in Cerebral Infarction (mTICI) grade ≥ 2b, initial and postprocedural Pediatric National Institutes of Health Stroke Scale (PedNIHSS) score, and pediatric modified Rankin scale (mRS) score 0 to 2 at 90 d., Results: There were 23 thrombectomies in 21 patients (mean age 11.6 ± 4.9 yr, median 11.5, range 2.1-19; 52% female). A total of 19 (83%) thrombectomies resulted in mTICI grade ≥ 2b recanalization. The median PedNIHSS score was 13 on presentation (range 4-33) and 2 (range 0-26) at discharge (mean reduction 11.3 ± 6.1). A total of 14 (66%) patients had a mRS score of 0 to 2 at 30-d follow-up; 18/21 (86%) achieved that by 90 d. The median mRS was 1 (range 0-4) at 30 d and 1 (range 0-5) at 90 d. One patient required a blood transfusion after thrombectomy., Conclusion: In this large series of pediatric patients treated with endovascular thrombectomy, successful recanalization was accomplished via a variety of approaches with excellent clinical outcomes; further prospective longitudinal study is needed., (Copyright © 2020 by the Congress of Neurological Surgeons.)

Background: First-pass efficacy (FPE) is an established marker of technical and clinical efficacy among mechanical thrombectomy (MT) techniques. It is unclear what the optimal approach is in achieving FPE. We present a single-center experience comparing rates of FPE among 2 MT techniques and evaluate the potential predictors of FPE among other outcomes., Methods: A single-center retrospective analysis was carried out of patients with consecutive large-vessel occlusion strokes (LVOS) of anterior circulation from September 2015 to April 2019 who underwent MT and for whom data were available on the status of FPE. Four MT techniques were identified: ADAPT (a direct first-pass aspiration), SrADAPT (stent retriever with aspiration), SRBG (stent retriever with balloon guide catheter), and STRAP (stent retriever-aspiration and proximal flow arrest). The primary outcome was FPE and secondary outcomes included the rate of successful reperfusion., Results: Among 226 patients with LVOS of the anterior circulation who underwent MT, data were available for 164 on FPE for the 4 MT techniques. SRBG was the most prevalent technique. No significant difference was found in rates of FPE among the 4 MT techniques (P = 0.332). No independent predictors of FPE were identified on multivariable analysis. STRAP had the highest rate of successful reperfusion compared with the other techniques (P = 0.049) and was the only independent predictor of that outcome (P = 0.027)., Conclusions: Among patients with LVOS of the anterior circulation, the rate of FPE did not differ among the 4 MT techniques. There were no predictors of FPE among the studied variables. STRAP was the only predictor of successful reperfusion., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: The Pipeline Embolization Device (PED; Medtronic) has been used off-label for the treatment of challenging posterior circulation aneurysms. Data on this modality are primarily limited to small retrospective single-center series., Objective: To assess safety and efficacy of this treatment by establishing an international, multicenter collaboration., Methods: Consecutive posterior circulation aneurysms treated with the PED from 2012 to 2019 across 11 neurovascular centers were retrospectively reviewed. Baseline demographics, aneurysm and treatment characteristics, complications, occlusion status, and functional outcome were assessed., Results: There were 149 posterior circulation aneurysms treated with PED in 146 patients. A total of 24 (16.4%) patients presented with subarachnoid hemorrhage. Most aneurysms were dissecting/blister (36.2%) in morphology, followed by saccular (35.6%) and fusiform (28.2%). The most common locations were the vertebral (51.7%) and basilar arteries (22.8%). Complete or near-complete occlusion (>90%) was achieved in 90.9% of aneurysms at a median follow-up of 12 mo. Dissecting/blister aneurysms were most likely to occlude (P = .06). Symptomatic neurologic complications occurred in 9.4% of aneurysms, associated with larger size, ruptured presentation, presentations with brain stem compression, cranial nerve palsy, or stroke. Favorable functional outcome (modified Rankin Score 0-2) was achieved in 86.2% of patients. There were 6 fatalities of which 4 occurred in aneurysmal subarachnoid hemorrhage patients., Conclusion: This multicenter study shows that PED for the treatment of posterior circulation is preferentially used for the treatment of fusiform and dissecting/blister aneurysm morphologies. Despite the challenges presented by these less-common morphologies, flow diversion may be performed with a neurologic complication rate of about 10% and favorable long-term aneurysm occlusion rates., (Copyright © 2020 by the Congress of Neurological Surgeons.)