Combined Technique for Internal Carotid Artery Terminus or Middle Cerebral Artery Occlusions in the ASTER2 Trial.

BACKGROUND: The aim of this study was to report the results of a subgroup analysis of the ASTER2 trial (Effect of Thrombectomy With Combined Contact Aspiration and Stent Retriever vs Stent Retriever Alone on Revascularization in Patients With Acute Ischemic Stroke and Large Vessel Occlusion) comparing the safety and efficacy of the combined technique (CoT) and stent retriever as a first-line approach in internal carotid artery (ICA) terminus±M1-middle cerebral artery (M1-MCA) and isolated M1-MCA occlusions. METHODS: Patients enrolled in the ASTER2 trial with ICA terminus±M1-MCA and isolated M1-MCA occlusions were included in this subgroup analysis. The effect of first-line CoT versus stent retriever according to the occlusion site was assessed on angiographic (first-pass effect, expanded Treatment in Cerebral Infarction score ≥2b50, and expanded Treatment in Cerebral Infarction score ≥2c grades at the end of the first-line strategy and at the end of the procedure) and clinicoradiological outcomes (24-hour National Institutes of Health Stroke Scale, ECASS-III [European Cooperative Acute Stroke Study] grades, and 3-month modified Rankin Scale). RESULTS: Three hundred sixty-two patients were included in the postsubgroup analysis according to the occlusion site: 299 were treated for isolated M1-MCA occlusion (150 with first-line CoT) and 63 were treated for ICA terminus±M1-MCA occlusion (30 with first-line CoT). Expanded Treatment in Cerebral Infarction score ≥2b50 (odds ratio, 11.83 [95% CI, 2.32-60.12]) and expanded Treatment in Cerebral Infarction score ≥2c (odds ratio, 4.09 [95% CI, 1.39-11.94]) were significantly higher in first-line CoT compared with first-line stent retriever in patients with ICA terminus±M1-MCA occlusion but not in patients with isolated M1-MCA. CONCLUSIONS: First-line CoT was associated with higher reperfusion grades in patients with ICA terminus±M1-MCA at the end of the procedure. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03290885.

Value of intravenous alteplase before thrombectomy among patients with tandem lesions and emergent carotid artery stenting: A subgroup analysis of the SWIFT DIRECT trial.

BACKGROUND AND PURPOSE: The value of intravenous thrombolysis (IVT) in eligible tandem lesion patients undergoing endovascular treatment (EVT) is unknown. We investigated treatment effect heterogeneity of EVT + IVT versus EVT-only in tandem lesion patients. Additional analyses were performed for patients undergoing emergent internal carotid artery (ICA) stenting. METHODS: SWIFT DIRECT randomized IVT-eligible patients to either EVT + IVT or EVT-only. Primary outcome was 90-day functional independence (modified Rankin Scale score 0-2) after the index event. Secondary endpoints were reperfusion success, 24 h intracranial hemorrhage rate, and 90-day all-cause mortality. Interaction models were fitted for all predefined outcomes. RESULTS: Among 408 included patients, 63 (15.4%) had a tandem lesion and 33 (52.4%) received IVT. In patients with tandem lesions, 20 had undergone emergent ICA stenting (EVT + IVT: 9/33, 27.3%; EVT: 11/30, 36.7%). Tandem lesion did not show treatment effect modification of IVT on rates of functional independence (tandem lesion EVT + IVT vs. EVT: 63.6% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 65.6% vs. 58.2%; p for interaction = 0.77). IVT also did not increase the risk of intracranial hemorrhage  among tandem lesion patients (tandem lesion EVT + IVT vs. EVT: 34.4% vs. 46.7%, non-tandem lesion EVT + IVT vs. EVT: 33.5% vs. 26.3%; p for interaction = 0.15). No heterogeneity was noted for other endpoints (p for interaction > 0.05). CONCLUSIONS: No treatment effect heterogeneity of EVT + IVT versus EVT-only was observed among tandem lesion patients. Administering IVT in patients with anticipated emergent ICA stenting seems safe, and the latter should not be a factor to consider when deciding to administer IVT before EVT.

The Bicêtre occlusion scale is well suited to assess the efficacy of the Contour embolization device.

BACKGROUND: The Contour Embolization Device (CED) is typically assessed using coiling angiographic outcomes. However, these scales do not address device-specific problematics. We evaluated the usability of the Bicêtre occlusion scale (BOS) with the CED. RESULTS: BOS scores can be analyzed as BOSS 0 = no residual flow, BOSS 1 = residual flow inside the CED but with complete neck-sealing, BOSS 2 = neck-remnant, BOSS 3 = aneurysm-remnant, BOSS 1 + 3 = contrast filling inside the device and aneurysmal sac without complete neck-sealing. CONCLUSION: BOS usage should be encouraged as it provides a more comprehensive assessment of the mechanism of CED occlusion, especially considering the potential prognostic value of the neck sealing assessment.

Impact of Day 1 carotid patency on outcome in dissection-related tandem occlusions treated with mechanical thrombectomy.

BACKGROUND: The clinical benefit of mechanical thrombectomy(MT) for stroke patients with tandem occlusion is similar to that of isolated intracranial occlusions. However, the management of cervical internal carotid artery(ICA) occlusion during the MT, particularly in the setting of carotid dissection, remains controversial. We aimed to investigate the clinical impact of cervical ICA patency at day 1 on 3-month functional outcome. METHODS: We collected data from the Endovascular Treatment in Ischemic Stroke, a prospective national registry in 30 French centers performing MT between January 2015 and January 2022. Inclusion criteria were consecutive tandem occlusions related to cervical ICA dissection treated with MT. Tandem occlusions of other etiology, isolated cervical ICA occlusions without intracranial thrombus and patients without day-1 ICA imaging were excluded. Primary endpoint was the 3-month functional outcome. Secondary endpoints included intracranial hemorrhage(ICH), excellent outcome, mortality and early neurological improvement. A sensitivity analysis was performed in patients with intracranial favorable recanalization after MT. RESULTS: During the study period, 137 patients were included of which 89(65%) presented ICA patency at day 1. The odds of favorable outcome did not significantly differ between patients with patent and occluded ICA at day 1(68.7 vs 59.1%;aOR=1.30;95%CI 0.56-3.00,p=0.54). Excellent outcome, early neurological improvement, mortality and ICH were also comparable between groups. Sensitivity analysis showed similar results. CONCLUSION: ICA patency at day 1 in patients with tandem occlusions related to dissection did not seem to influence functional outcome. Endovascular recanalization of the cervical ICA including stenting might not be systematically required in this setting.

Early Recanalization Among Patients Undergoing Bridging Therapy With Tenecteplase or Alteplase.

BACKGROUND: Intravenous thrombolysis (IVT) with alteplase or tenecteplase before mechanical thrombectomy is the recommended treatment for large-vessel occlusion acute ischemic stroke. There are divergent data on whether these agents differ in terms of early recanalization (ER) rates before mechanical thrombectomy, and little data on their potential differences stratified by ER predictors such as IVT to ER evaluation (IVT-to-EReval) time, occlusion site and thrombus length. METHODS: We retrospectively compared the likelihood of ER after IVT with tenecteplase or alteplase in anterior circulation large-vessel occlusion acute ischemic stroke patients from the PREDICT-RECANAL (alteplase) and Tenecteplase Treatment in Ischemic Stroke (tenecteplase) French multicenter registries. ER was defined as a modified Thrombolysis in Cerebral Infarction score 2b-3 on the first angiographic run, or noninvasive vascular imaging in patients with early neurological improvement. Analyses were based on propensity score overlap weighting (leading to exact balance in patient history, stroke characteristics, and initial management between groups) and confirmed with adjusted logistic regression (sensitivity analysis). A stratified analysis based on pre-established ER predictors (IVT-to-EReval time, occlusion site, and thrombus length) was conducted. RESULTS: Overall, 1865 patients were included. ER occurred in 156/787 (19.8%) and 199/1078 (18.5%) patients treated with tenecteplase or alteplase, respectively (odds ratio, 1.09 [95% CI, 0.83-1.44]; P=0.52). A differential effect of tenecteplase versus alteplase on the probability of ER according to thrombus length was observed (Pinteraction=0.003), with tenecteplase being associated with higher odds of ER in thrombi >10 mm (odds ratio, 2.43 [95% CI, 1.02-5.81]; P=0.04). There was no differential effect of tenecteplase versus alteplase on the likelihood of ER according to the IVT-to-EReval time (Pinteraction=0.40) or occlusion site (Pinteraction=0.80). CONCLUSIONS: Both thrombolytics achieved ER in one-fifth of patients with large-vessel occlusion acute ischemic stroke without significant interaction with IVT-to-EReval time and occlusion site. Compared with alteplase, tenecteplase was associated with a 2-fold higher likelihood of ER in larger thrombi.

Endovascular Management of Brain Arteriovenous Malformations.

Due to the risk of cerebral hemorrhage, and its related morbidity-mortality, brain arteriovenous malformations (bAVMs) are a rare and potentially life-threatening disease. Despite this, there is only one randomized controlled trial on bAVM management, A Randomized trial of Unruptured Brain Arteriovenous malformations (ARUBA). The results of the ARUBA trial favor a noninterventional approach in the case of an unruptured bAVM; however, implementation of these findings is challenging in daily practice. Instead, management of bAVM relies on multidisciplinary discussions that lead to patient-specific strategies based on patient preferences, local expertise, and experience in referral centers. Considering the diverse patterns of presentation and numerous treatment modalities, implementing standardized guidelines in this context proves challenging, notwithstanding the recommendations or expert opinions offered. Endovascular treatment (EVT) of bAVM can be curative, or can serve as an adjunct treatment prior to surgery or radiosurgery ("pre-EVT"). EVT practice is in constant evolution (i.e., venous approach, combination with surgery during the same anesthesia, etc.). Liquid embolic agents such as ethylene vinyl alcohol (EVOH) copolymer and cyanoacrylates (CYA), and their method of injection to increase bAVM occlusion have also benefited from technical evolutions such as the use of adjunctive flow arrest techniques (mini balloons, pressure cooker technique, and multiple catheters). Further research is necessary to evaluate the advantages and disadvantages of EVT for bAVM.

How a decade of aneurysms embolization with the Woven EndoBridge has changed our understanding and practices?

BACKGROUND: Safety and efficacy of the WEB (Woven EndoBridge) device have been extensively evaluated in several good clinical practice studies. Nonetheless, the WEB had several structural evolutions overtime up to the fifth generation WEB device (WEB17). Here, we tried to understand how this may have modified our practices and enlarged our indications for its use. METHODS: We retrospectively analyzed data from all patients with aneurysms treated (or intended to be treated) with a WEB at our institution between July 2012 and February 2022. The time frame was split in two periods: before and after the arrival of the WEB17 in our center (February 2017). RESULTS: 252 patients with 276 wide-necked aneurysms were included; 78 aneurysms (28.2%) were ruptured. Successful embolization with a WEB device was achieved in 263/276 aneurysms (95.3%). With the availability of WEB17, treated aneurysms were significantly smaller (8.2 mm versus 5.9 mm, p<0.001) and off-label location significantly increased (4.4% versus 17.3%, p = 0.02) with an increase of sidewall aneurysm (4.4% versus 11.6%, p = 0.06). Also, WEB were more significantly oversized (1.05 versus 1.11, p<0.01). Adequate and complete occlusion rates increased constantly during the two periods (54.8% versus 67.5%, p = 0.08 and 74.2% versus 83.7%, p = 0.10, respectively). The proportion of ruptured aneurysms slightly increased between the two periods (24.6% versus 29.5%, p = 0.44). CONCLUSIONS: Over the first decade of its availability, the WEB device usage shifted towards smaller aneurysms and broader indications, including ruptured aneurysms. The oversizing strategy also became the standard of practice for WEB deployment in our institution.

Effects of weather conditions on endovascular treatment case volume for patients with ischemic stroke.

BACKGROUND: Weather conditions have been shown to influence the occurrence of cardiovascular events. We tested the hypothesis that weather parameters may be associated with variations of case volume of endovascular treatment (EVT) for acute ischemic stroke. METHODS: Individual data from the ETIS (Endovascular Treatment in Ischemic Stroke) French national registry were matched to local weather stations. Meteorological parameters (rainfall, humidity, atmospheric pressure, air temperature) were gathered from national online resources. Weather readings and EVT case volumes were annually standardized per weather station and EVT center, and their associations tested with non-parametric univariable and generalized linear statistical models. RESULTS: Between 2015 and 2021, 9913 EVT procedures addressed by 135 primary stroke units were matched to weather conditions. The mean daily case volume per center was 0.41 [StDev 0.33], and there was a median of 0.84 procedures daily linked to a weather station [StDev 0.47]. We found lower atmospheric pressure (ß estimate -0.04; 95%CI[-0.07;-0.03], p<0.001), higher humidity (ß estimate 0.07; 95%CI [0.05;0.09], p<0.001) and lower temperatures (ß estimate -0.08; 95%CI[-0.10;-0.06], p<0.001) to be associated with higher standardized EVT daily case volumes. These associations were stable when testing them across strata of binned EVT standardized case volumes. CONCLUSIONS: Our study suggests that lower ambient temperature, lower atmospheric pressure, and higher air humidity are associated with significantly more daily EVT cases in a European temperate country. These results may provide insight into both system of care optimization at times of climate change and intracranial LVO pathophysiology. REGISTRATION-URL: https://clinicaltrials.gov/ct2/show/NCT03776877.

Dual-layer carotid stenting for symptomatic carotid web: Results from the Caroweb study.

BACKGROUND & PURPOSE: Carotid Web (CaW) is a growingly recognized cause of ischemic stroke, associated with a high recurrence risk. Several therapeutic strategies have been proposed as a tertiary prevention including carotid stenting, endarterectomy and antithrombotic medications. Among these, carotid stenting with dual-layer stent may be promising to adequately cover the focal arterial dysplasia. Our aim was to investigate the safety and efficacy of the Casper stent in the treatment of symptomatic CaW. METHODS: We conducted a retrospective analysis of consecutive patients presenting with a symptomatic CaW and included in the ongoing prospective observational multicenter CAROWEB registry. The study period was January 2015 to December 2021. Inclusion criteria were CaW treated with dual-layer Casper stent. Patients treated with other types of carotid stent, endarterectomy or antithrombotic medication were excluded. Clinical and radiological initial data and outcomes were recorded. RESULTS: twenty-seven patients (with 28 caw) were included. median age was 52 (iqr: 46-68). median delay between index cerebrovascular event and cervical stenting was 9 days (IQR: 6-101). In all cases, the cervical carotid stenting was successfully performed. No major perioperative complication was recorded. No recurrent stroke or transient ischemic attack was observed during a median follow-up time of 272 days (IQR: 114-635). Long-term imaging follow-up was available in 25/28 (89.3%) stented CaW with a median imaging follow-up of 183 days (IQR: 107-676; range: 90-1542). No in-stent occlusion or stenosis was detected. CONCLUSION: In this study, carotid stenting with dual-layer Casper stent in the treatment of symptomatic CaW was effective regarding stroke recurrence prevention and safe, without procedural nor delayed detected adverse event. However, the optimal therapeutic approach of symptomatic CaW still needs to be explored through randomized trials.

Mechanical thrombectomy failure in anterior circulation strokes: Outcomes and predictors of favorable outcome.

BACKGROUND AND PURPOSE: Despite continuous improvement and growing knowledge in the endovascular therapy of large vessel occlusion stroke (LVOS), mechanical thrombectomy (MT) still fails to obtain satisfying intracranial recanalization in 10% to 15% of cases. However, little is known regarding clinical and radiological outcomes among this singularly underexplored subpopulation undergoing failed MT. We aimed to investigate the outcome after failed MT and identify predictive factors of favorable outcome despite recanalization failure. METHODS: We conducted a retrospective analysis of consecutive patients prospectively included in the ongoing observational multicenter Endovascular Treatment in Ischemic Stroke registry from January 2015 to September 2020. Patients presenting with anterior circulation LVOS treated with MT but experiencing failed intracranial recanalization defined as final modified Thrombolysis In Cerebral Infarction (mTICI) score of 0, 1 and 2a were included. Clinical and radiological outcomes were assessed along with the exploration of predictive factors of Day-90 favorable outcome. RESULTS: The study population comprised 533 patients. Mean age was 68.8 ± 16 years, and median admission National Institutes of Health Stroke Scale (NIHSS) and Alberta Stroke Program Early Computed Tomography Score (ASPECTS) were 17 (IQR 12-21) and 7 (IQR 5-8), respectively. Favorable outcomes were observed in 85 patients (18.2%) and 186 died (39.0%). The rate of symptomatic intracranial hemorrhage was 14.1%. In multivariable analysis, younger age (odds ratio [OR] 0.96, 95% CI 0.94-0.98, p < 0.001), a lower admission NIHSS (OR 0.87, 95% CI 0.83-0.91, p < 0.001), a lower number of MT passes (OR 0.77, 95% CI 0.77-0.87, p < 0.001), a lower delta ASPECTS between initial and Day-1 imaging (OR 0.83, 95% CI 0.71-0.98, p = 0.026) and stroke etiology [significant difference among etiological subtypes (p = 0.024) with a tendency toward more favorable outcomes for dissection (OR 2.01, 95% CI 0.71-5.67)] were significantly associated with a 90-day favorable outcome. CONCLUSIONS: In this large retrospective analysis of a multicenter registry, we quantified the poor outcome after MT failure. We also identified factors associated with favorable outcome despite recanalization failure that might influence therapeutic management.

Intracranial Aneurysm in Pediatric Population: A Single-Center Experience.

PURPOSE: Pediatric intracranial aneurysms (PIA) are rarer and more complex when compared to adult aneurysms. In general, the clinical presentation of PIA is due to a mass effect, but the presenting symptoms can be also related to ischemia, subarachnoid hemorrhage (SAH), or in a combination of different symptoms. This paper aimed to report a single-center experience with clinical and angiographic aspects of brain aneurysm in children. METHODS: We retrospectively reviewed our prospectively maintained database for patients with intracranial aneurysms in our institution from July 2015 to February 2021. Among these, all patients under 18 years of age submitted to a diagnostic or therapeutic procedure for an intracranial aneurysm were included. RESULTS: Twelve patients were submitted to diagnostic or therapeutic procedures in our department. Three of them had multiple aneurysms, and in total, 17 intracranial aneurysms were assessed in this study. The most frequent location was in the middle cerebral artery (7 cases/41%). Five out of twelve children (42%) presented SAH due to ruptured aneurysm. Three patients (25%) had symptoms due to the mass effect from large aneurysms, with compression of cranial nerves or brainstem. Aneurysms diameters ranged from 1.5 mm to 34 mm (mean 14.2 mm), with six aneurysms being giant and eight being nonsaccular/fusiform. Twelve aneurysms were submitted to endovascular treatment, with one treatment-related clinical complication and later death. CONCLUSION: PIAs are rare diseases that can arise from a variety of different underlying pathological mechanisms. The management of these conditions requires a detailed understanding of the pathology and a multidisciplinary approach. Despite the availability of new technologies, parent vessel occlusion remains a valid option for aneurysms in the pediatric population.

CD31 Mimetic Coating Enhances Flow Diverting Stent Integration into the Arterial Wall Promoting Aneurysm Healing.

BACKGROUND AND PURPOSE: Beyond aneurysmal occlusion, metallic flow diverters (FDs) can induce an adverse endovascular reaction due to the foreignness of metal devices, hampering FD endothelialization across the aneurysm neck, and arterial healing of intracranial aneurysms. Here, we evaluated the potential benefits of an FD coating mimicking CD31, a coreceptor critically involved in endothelial function and endovascular homeostasis, on the endothelialization of FDs implanted in vivo. METHODS: Nitinol FD (Silk Vista Baby) and flat disks were dip-coated with a CD31-mimetic peptide via an intermediate layer of polydopamine. Disks were used to assess the reaction of endothelial cells and blood elements in vitro. An aneurysm rabbit model was used to compare in vivo effects on the arterial wall of CD31-mimetic-coated (CD31-mimetic, n=6), polydopamine-coated (polydopamine, n=6), and uncoated FDs (bare, n=5) at 4 weeks post-FD implantation. In addition, long-term safety was assessed at 12 weeks. RESULTS: In vitro, CD31-mimetic coated disks displayed reduced adhesion of blood elements while favoring endothelial cell attachment and confluence, compared to bare and polydopamine disks. Strikingly, in vivo, the neoarterial wall formed over the CD31-mimetic-FD struts at the aneurysm neck was characteristic of an arterial tunica media, with continuous differentiated endothelium covering a significantly thicker layer of collagen and smooth muscle cells as compared to the controls. The rates of angiographic complete occlusion and covered branch arterial patency were similar in all 3 groups. CONCLUSIONS: CD31-mimetic coating favors the colonization of metallic endovascular devices with endothelial cells displaying a physiological phenotype while preventing the adhesion of platelets and leukocytes. These biological properties lead to a rapid and improved endothelialization of the neoarterial wall at the aneurysm neck. CD31-mimetic coating could therefore represent a valuable strategy for FD biocompatibility improvement and aneurysm healing.

Y-stenting with braided stents for wide-neck intracranial bifurcation aneurysms. A single-center initial experience.

INTRODUCTION: The treatment of wide-neck bifurcation aneurysms is still challenging despite the use of new techniques, such as Y-stenting, the waffle-cone technique and intrasaccular flow disrupters, in recent years. Moreover, the use of flow diverter stents in bifurcation aneurysms has been proposed by several teams, although the results remain controversial. This study aims to evaluate the feasibility and efficacy of Y-stent assisted coiling of bifurcation aneurysms with braided stents. METHODS: We retrospectively reviewed all patients in whom Y-stenting with braided stents had been performed in our center. Six patients were identified and analyzed. Technical success, complications, angiographic outcomes, procedural data, and follow-up controls are reported here. This study was approved by our local ethical committee. RESULTS: Technical success was achieved in all procedures. Overall procedure-related morbidity and mortality was 0%. In the immediate post-treatment angiography, adequate occlusion (neck remnant or total occlusion) was observed in all patients. Short- and long-term follow-up angiography showed adequate occlusion of the aneurysms. CONCLUSIONS: In this small, retrospective single-center analysis we showed that Y-stent assisted coiling with braided stents is a safe and feasible technique. Moreover, it has a high immediate occlusion rate and very good long-term stability.

The PHASES score: To treat or not to treat? Retrospective evaluation of the risk of rupture of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: The PHASES score was formulated to predict the 5-year risk of rupture for intracranial aneurysms. We retrospectively analyzed all patients treated in our institution for aneurysmal SAH and applied the PHASES score to estimate the probable predicted risk of bleeding in this group of patients. METHODS: Between February 2015 and August 2018, all patients with aneurysmal SAH were retrospectively analyzed and the PHASES score was applied. A total of 155 patients were included with a mean age of 53.8years, including 60 males and 95 females. RESULTS: Of our patients 110 (70.9%) had a PHASES score of below or equal to 5, with a hemorrhagic risk of up to 1.3% over 5years. If we analyze the patients with a risk of below 2% this figure increases to 122 patients (78.7%). Of these 99.3% were European and 0.6% were Japanese (1 patient). In 86 patients (55.4%), the aneurysm was smaller than 5mm and in 10 patients (6.4%) the aneurysm was located in the posterior circulation. CONCLUSION: Of our patients 78.7% had less than a 2% 5-year rupture risk based on their PHASES score, highlighting the discrepancy of the rupture risk calculated with the PHASES score when hypothetically applied to this group of patients. In the hypothetical scenario that our patients had unruptured aneurysms, our retrospective analysis shows that the PHASES score may only provide a weak tool for clinicians to use in the decision-making process as to whether or not to treat these aneurysms.

Thrombectomy or intravenous thrombolysis in patients with NIHSS of 5 or less?

BACKGROUND AND PURPOSE: To compare outcomes of minor stroke patients with intracranial vessel occlusions (IVO) underwent mechanical thrombectomy (MT) versus those treated with intravenous thrombolysis alone (IVT). METHODS: We retrospectively reviewed two large prospective stroke databases from two European centers searching for patients admitted with minor stroke (i.e. NIHSS Score░≤░5), baseline mRS░=░0 and occlusion of the M1-M2 segment of the middle cerebral artery (MCA). Groups receiving (A) IVT alone and (B) MT+/-IVT were compared. Primary outcome measures were MT safety, successful recanalization rate (mTICI 2b-3) and NIHSS shift (discharge NIHSS minus admission NIHSS); secondary outcomes included discharge rates and excellent outcome (mRS 0-1) at 3 months. Univariate and multivariate analyses were performed. RESULTS: Thirty-two patients were enrolled in Group B (19░MT alone; 13 MT░+░IVT) and 24 in Group A. Successful recanalization (mTICI 2b-3) was obtained in 100% of cases in Group B vs 38% in Group A. Symptomatic hemorrhagic transformation rate did not differ between the two groups. Multivariate analysis reported MT as the only predictor of early (<░12░h) favorable NIHSS shift and lower NIHSS at discharge. Moreover, discharge at home and excellent outcome at 3-month follow-up were statistically associated with MT. CONCLUSIONS: MT in patients with minor strokes and intracranial vessel occlusion (IVO) is safe and can determine a rapid improvement of NIHSS Score. MT seems also associated with a higher rate of patients discharged at home after hospitalization and better clinical outcome at 3-month follow-up. Larger randomized trials are warranted to confirm these results.

A new time-resolved 3D angiographic technique (4D DSA): Description, and assessment of its reliability in Spetzler-Martin grading of cerebral arteriovenous malformations.

BACKGROUND AND PURPOSE: The Spetzler and Martin (SM) cerebral arteriovenous malformation (AVM) classification is a widely used 5-tier classification. This common language allows specialists to exchange about AVMs and must be reliably characterized by the imaging methods. We presented an agreement study on a new method of digital subtracted 3D rotational angiography resolved in time (four-dimensional DSA: 4D DSA) compared to the gold standard (two-dimensional DSA: 2D DSA) in AVM grading using the SM classification. METHODS: Ten patients with AVMs were included during one year, they had an angiographic exploration with both 4D DSA and 2D DSA. Three readers assessed the SM classification. One reader conducted a second reading. The inter-, intra-observer and intermodality agreements were calculated by Kappas. Dose to patient was reported. RESULTS: Considering the SM grade, the inter-observer agreement between 4D DSA and 2D DSA was equivalent (κ=0.45 and 0.46), and calculated as substantial κ=0.76 between the 2 methods. The agreement between 4D DSA and 2D DSA was calculated as moderate κ=0.46 assessing the size of the nidus, slight κ=0.18 analyzing the drainage and almost perfect κ=0.95 depicting the localization. 4D DSA performed during a standard initial angiographic assessment of AVM represented approximately 6% of the total dose. CONCLUSION: The addition of this new technique 4D DSA could be performed regularly in addition to the 2D DSA if available, to assess SM grading, with an acceptable exposure to ionizing radiation.

A computational fluid dynamics (CFD) study of WEB-treated aneurysms: Can CFD predict WEB "compression" during follow-up?

BACKGROUND: Recent reports have revealed a worsening of aneurysm occlusion between WEB treatment baseline and angiographic follow-up due to "compression" of the device. OBJECTIVE: We utilized computational fluid dynamics (CFD) in order to determine whether the underlying mechanism of this worsening is flow related. METHODS: We included data from all consecutive patients treated in our institution with a WEB for unruptured aneurysms located either at the middle cerebral artery or basilar tip. The CFD study was performed using pre-operative 3D rotational angiography. From digital subtraction follow-up angiographies patients were dichotomized into two groups: one with WEB "compression" and one without. We performed statistical analyses to determine a potential correlation between WEB compression and CFD inflow ratio. RESULTS: Between July 2012 and June 2015, a total of 22 unruptured middle cerebral artery or basilar tip aneurysms were treated with a WEB device in our department. Three patients were excluded from the analysis and the mean follow-up period was 17months. Eleven WEBs presented "compression" during follow-up. Interestingly, device "compression" was statistically correlated to the CFD inflow ratio (P=0.018), although not to aneurysm volume, aspect ratio or neck size. CONCLUSION: The mechanisms underlying the worsening of aneurysm occlusion in WEB-treated patients due to device compression are most likely complex as well as multifactorial. However, it is apparent from our pilot study that a high arterial inflow is, at least, partially involved. Further theoretical and animal research studies are needed to increase our understanding of this phenomenon.

Occlusion assessment of intracranial aneurysms treated with the WEB device.

INTRODUCTION: The Woven EndoBridge (WEB) system is an innovative device under evaluation for its capacity to treat wide-neck bifurcation intracranial aneurysms. The purpose of this study is to evaluate the use of the different occlusion scales available in clinical practice. METHODS: Seven WEB-experienced neurointerventionalists were provided with 30 angiographic follow-up data sets and asked to grade each evaluation point according to the Bicêtre Occlusion Scale Score (BOSS), firstly based on DSA images only then using additional C-Arm VasoCT analysis. This BOSS evaluation was then converted into the WEB Occlusion Scale (WOS) and into a dichotomized scale (complete occlusion or not). To estimate the inter-rater agreement among the seven raters, an overall kappa coefficient [1] and its standard error (SE) were computed. RESULTS: Using the five-grade BOSS, raters showed "moderate" agreement (kappa = 0.56). Using the three-grade WOS, agreement appeared slightly better (kappa = 0.59). Strongest inter-rater agreement was observed with a dichotomized version of the scale (complete occlusion or not), which enabled an "almost perfect" agreement (kappa = 0.88). VasoCT consistently enhanced the agreement particularly with regards depicting intra-WEB residual filling. CONCLUSION: The WOS is a consistent means to angiographically evaluate the WEB device efficiency. But the five-grade BOSS scale allows to identify aneurysm subgroups with differing risks of recurrence and/or rehemorrhage, which needs to be separated especially at the initial phase of evaluation of this innovative device. The additional use of VasoCT allows better inter-rater agreement in evaluating occlusion and specially in depicting intra-WEB persistent filling.

Woven Endobridge (WEB) Device for endovascular treatment of ruptured intracranial wide-neck aneurysms: a single-center experience.

INTRODUCTION: Endovascular treatment of ruptured wide-neck bifurcation aneurysms presents a challenge. While still under evaluation, the Woven Endobridge (WEB) aneurysm embolization system has so far shown promising results in the treatment of complex bifurcation aneurysms. We aimed to evaluate the feasibility and short-term follow-up of endovascular treatment of ruptured wide-neck aneurysm with the WEB device. METHODS: Six patients referred to our institution for acute symptomatic subarachnoid hemorrhage (SAH) and treated with the WEB device were enrolled in this study. Clinical presentations, technical details, intraoperative and postoperative complications, and outcomes were recorded. Immediate and 3-month angiographic results were also evaluated. RESULTS: Three middle cerebral artery (MCA) and three anterior communicating artery aneurysms were treated between 1 and 14 days after rupturing. Average dome width was 5.8 mm (range 5-7), average neck size was 4.5 mm (range 4-5), and average dome-to-neck ratio was 1.3 (range 1-1.7). The WEB system was the exclusive treatment and was successfully deployed in all cases. Per procedural thromboembolic events occurred in two cases and were treated with intra-arterial administration of antiplatelet agents without any clinical consequences. The modified Rankin Scale (mRS) score at discharge was 0 for all patients. The 3-month angiographic follow-up showed adequate occlusion in four of our six patients (67 %). CONCLUSION: From this preliminary study, the high feasibility rate and lack of need for systematic antiplatelet agents favor the WEB device providing a solution for endovascular treatment of ruptured wide-neck bifurcation aneurysms during the acute phase. However, further studies are needed to evaluate the complication rate and long-term efficiency.