Frequency and predictors of decompressive craniectomy in ischemic stroke patients treated by mechanical thrombectomy in the ETIS registry.

BACKGROUND AND AIMS: Mechanical thrombectomy (MT) for patients with acute ischemic stroke (AIS) is usually performed in a comprehensive stroke center with on-site neurosurgical expertise. The question of whether MT can be performed in a primary stroke center without a neurosurgical facility is debated. In this context, there is a need to determine the frequency, delay and predictors of neurosurgical procedures in patients treated by MT. This study aims to determine these factors. METHODS: In total, 432 patients under 60years old, diagnosed with an acute ischemic stroke with a large vessel occlusion and treated by MT between January 2018 and December 2019 in six French stroke centers, were selected from the French clinical registry ETIS. Univariate and multivariate logistic regression models were used to identify predictive factors for decompressive craniectomy. RESULTS: Among the 432 included patients, 43 (9.9%) patients with an anterior circulation infarct underwent decompressive craniectomy. Higher admission NIHSS (OR: 1.08 [95% CI: 1.02-1.16]), lower ASPECT (OR per 1 point of decrease 1.53 [1.31-1.79] P<0.001) and preadmission antiplatelet use (OR: 3.03 [1.31-7.01]) were independent risk factors for decompressive craniectomy. The risk of decompressive craniectomy increases to more than 30% with an ASPECT score<4, an NIHSS>16, and current antiplatelet use. CONCLUSION: In this multicenter registry, 9% of acute ischemic stroke patients (<60years old) treated with MT, required decompressive craniectomy. Higher NIHSS score, lower ASPECT score, and preadmission antiplatelet use increase the risk of subsequent requirement for decompressive craniectomy.

Automated Aortic Anatomy Analysis: from Image to Clinical Indicators.

Most cerebrovascular diseases (including strokes and aneurysms) are treated endovascularly with catheters that are navigated from the groin through the vessels to the brain. Many patients have complex anatomy of the aortic arch and supra-aortic vessels, which can make it difficult to select the best catheters for navigation, resulting in longer procedures and more complications or failures. To this end, we propose a framework dedicated to the analysis of the aortic arch and supra-aortic trunks. This framework can automatically compute anatomical and geometrical features from meshes segmented beforehand via CNN-based pipeline. These features such as arch type, tortuosity and angulations describe the navigational difficulties encountered during catheterization. Quantitative and qualitative validation was performed by experienced neuroradiologists, leading to reliable vessel characterization.Clinical relevance- This method allows clinicians to determine the type and the anatomy of the aortic arch and its supra-aortic trunks before endovascular procedures. This is essential in interventional neuroradiology, such as navigation with catheters in this complex area.

Parent Artery Straightening after Flow-Diverter Stenting Improves the Odds of Aneurysm Occlusion.

BACKGROUND AND PURPOSE: Intracranial stents for the treatment of aneurysms can be responsible for parent artery straightening, a phenomenon with potential consequences for aneurysmal occlusion. We aimed to evaluate parent artery straightening following flow-diverter stent placement in patients with intracranial aneurysms and explored the association between parent artery straightening and subsequent aneurysm occlusion. MATERIALS AND METHODS: All patients treated with flow-diverter stents for anterior circulation aneurysms located downstream from the carotid siphon between January 2009 and January 2018 were screened for inclusion. Parent artery straightening was defined as the difference (α-ß) in the parent artery angle at the neck level before (α angle) and after flow-diverter stent deployment (ß angle). We analyzed the procedural and imaging factors associated with parent artery straightening and the associations between parent artery straightening and aneurysmal occlusion. RESULTS: Ninety-five patients met the inclusion criteria (n = 64/95 women, 67.4%; mean age, 54.1 [SD, 11.2] years) with 97 flow-diverter stents deployed for 99 aneurysms. Aneurysms were predominantly located at the MCA bifurcation (n = 44/95, 44.4%). Parent artery straightening was found to be more pronounced in patients treated with cobalt chromium stents than with nitinol stents (P = .02). In multivariate analysis, parent artery straightening (P = .04) was independently associated with aneurysm occlusion after flow-diverter stent deployment. CONCLUSIONS: The use of flow-diverter stents for distal aneurysms induces a measurable parent artery straightening, which is associated with higher occlusion rates. Parent artery straightening, in our sample, appeared to be more prominent with cobalt chromium stents than with nitinol stents. This work highlights the necessary trade-off between navigability and parent artery straightening and may help tailor the selection of flow-diverter stents to aneurysms and parent artery characteristics.

Predictive factors of functional independence after optimal reperfusion in anterior circulation ischaemic stroke with indication for intravenous thrombolysis plus mechanical thrombectomy.

BACKGROUND AND PURPOSE: Intravenous thrombolysis plus mechanical thrombectomy (IVT + MT) is the best current management of acute stroke due to large-vessel occlusion and results in optimal reperfusion for most patients. Nevertheless, some of these patients do not subsequently achieve functional independence. The aim was to identify baseline factors associated with 3-month independence after optimal reperfusion and to validate a prediction model. METHODS: All consecutive patients with intracranial anterior large-vessel occlusion, with indication for IVT + MT and achieving optimal reperfusion (defined as modified Treatment in Cerebral Ischaemia score 2b-3), from the THRACE trial and the ETIS registry, were included in order to identify a prediction model. The primary outcome was 3-month independence [modified Rankin Scale (mRS) score ≤ 2]. Multivariate inferences invoked forward logistic regression, multiple imputation and bootstrap resampling. Predictive performance was assessed by c-statistic. Model validation was conducted on patients from the ASTER trial. RESULTS: Amongst 139 patients (mean age 65.5 years; 54.3% female), predictors of 3-month mRS ≤ 2 (n = 82) were younger age [odds ratio 0.62 per 10-year increase; 95% confidence interval (CI) 0.53-0.72] and higher Alberta Stroke Program Early Computed Tomography Score (ASPECTS) (odds ratio 1.65 per 1-point increase; 95% CI 1.47-1.86) with c-statistic 0.77. Model validation (n = 104/181 patients with 3-month mRS ≤ 2) demonstrated a moderate discrimination (c-statistic 0.74; 95% CI 0.66-0.81) combining age and ASPECTS. The validation model was improved by the adjunction of three candidate variables that were found to be predictors. Addition of baseline National Institutes of Health Stroke Scale (NIHSS) score, history of vascular risk factor and onset-to-reperfusion time significantly improved discrimination (c-statistic 0.85; 95% CI 0.83-0.87). CONCLUSIONS: After optimal reperfusion, younger age, higher ASPECTS, lower NIHSS score, shorter onset-to-reperfusion time and absence of vascular risk factor were predictive of independence and could help to guide patient management.

Clot Burden Score and Collateral Status and Their Impact on Functional Outcome in Acute Ischemic Stroke.

BACKGROUND AND PURPOSE: Collateral status and thrombus length have been independently associated with functional outcome in patients with acute ischemic stroke. It has been suggested that thrombus length would influence functional outcome via interaction with the collateral circulation. We investigated the individual and combined effects of thrombus length assessed by the clot burden score and collateral status assessed by a FLAIR vascular hyperintensity-ASPECTS rating system on functional outcome (mRS). MATERIALS AND METHODS: Patients with anterior circulation acute ischemic stroke due to large-vessel occlusion from the ASTER and THRACE trials treated with endovascular thrombectomy were pooled. The clot burden score and FLAIR vascular hyperintensity score were determined on MR imaging obtained before endovascular thrombectomy. Favorable outcome was defined as an mRS score of 0-2 at 90 days. Association of the clot burden score and the FLAIR vascular hyperintensity score with favorable outcome (individual effect and interaction) was examined using logistic regression models. RESULTS: Of the 326 patients treated by endovascular thrombectomy with both the clot burden score and FLAIR vascular hyperintensity assessment, favorable outcome was observed in 165 (51%). The rate of favorable outcome increased with clot burden score (smaller clots) and FLAIR vascular hyperintensity (better collaterals) values. The association between clot burden score and functional outcome was significantly modified by the FLAIR vascular hyperintensity score, and this association was stronger in patients with good collaterals, with an adjusted OR = 6.15 (95% CI, 1.03-36.81). CONCLUSIONS: The association between the clot burden score and functional outcome varied for different collateral scores. The FLAIR vascular hyperintensity score might be a valuable prognostic factor, especially when contrast-based vascular imaging is not available.

Neurological improvement predicts clinical outcome after acute basilar artery stroke thrombectomy.

BACKGROUND AND PURPOSE: Mechanical thrombectomy (MT) is the standard of care for patients with anterior circulation large vessel occlusion. Early neurological improvement (ENI), defined as a reduction of ≥ 8 on the National Institutes of Health Stroke Scale (NIHSS) compared with baseline score, or an NIHSS score of 0 or 1 at 24 h after MT, is a strong predictor of 3-month favorable outcome in such patients. The impact of ENI after MT in stroke patients with basilar artery occlusion (BAO) on 3-month outcome is not clear. We aimed to study the effects of ENI in patients with BAO. METHODS: We performed a retrospective analysis of a multicenter prospective cohort of all consecutive stroke patients with BAO who underwent MT. We compared clinical outcomes between BAO patient groups according to ENI status. Multivariate analyses were performed to determine the impact of ENI on favorable 90-day outcome (modified Rankin scale score 0-3) and to report factors contributing to ENI. RESULTS: A total of 237 patients were included. ENI was observed in 70 patients (30%). Outcomes were significantly better in ENI-positive patients, with 84% achieving favorable outcome (mRS score 0-3) at 3 months versus 30% for ENI-negative patients (P < 0.0001). In multivariate analysis, ENI was an independent predictive factor associated with higher rates of favorable outcome {odds ratio (OR) 18.12 [95% confidence interval (CI) 3.95-83.10]; P = 0.0001}. Higher number of passes [OR 0.62 (95% CI 0.43-0.89); P = 0.010] and need for stenting [OR 0.27 (95% CI 0.07-0.95); P = 0.041] were negatively associated with ENI. CONCLUSION: Early neurological improvement on day 1 following MT for BAO is a strong independent predictor of a favorable 3-month clinical outcome.

Fusion Image Guidance for Supra-Aortic Vessel Catheterization in Neurointerventions: A Feasibility Study.

BACKGROUND AND PURPOSE: Endovascular navigation through tortuous vessels can be complex. Tools that can optimise this access phase need to be developed. Our aim was to evaluate the feasibility of supra-aortic vessel catheterization guidance by means of live fluoroscopy fusion with MR angiography or CT angiography. MATERIALS AND METHODS: Twenty-five patients underwent preinterventional diagnostic MRA, and 8 patients underwent CTA. Fusion guidance was evaluated in 35 sessions of catheterization, targeting a total of 151 supra-aortic vessels. The time for MRA/CTA segmentation and fluoroscopy with MRA/CTA coregistration was recorded. The feasibility of fusion guidance was evaluated by recording the catheterizations executed by interventional neuroradiologists according to a standard technique under fluoroscopy and conventional road-mapping independent of the fusion guidance. Precision of the fusion roadmap was evaluated by measuring (on a semiquantitative 3-point scale) the maximum offset between the position of the guidewires/catheters and the vasculature on the virtual CTA/MRA images. The targeted vessels were divided in 2 groups according to their position from the level of the aortic arch. RESULTS: The average time needed for segmentation and image coregistration was 7 ± 2 minutes. The MRA/CTA virtual roadmap overlaid on live fluoroscopy was considered accurate in 84.8% (128/151) of the assessed landmarks, with a higher accuracy for the group of vessels closer to the aortic arch (92.4%; OR, 4.88; 95% CI, 1.83-11.66; P = .003). CONCLUSIONS: Fluoroscopy with MRA/CTA fusion guidance for supra-aortic vessel interventions is feasible. Further improvements of the technique to increase accuracy at the cervical level and further studies are needed for assessing the procedural time savings and decreasing the x-ray radiation exposure.

Large vessel stroke in six patients following SARS-CoV-2 infection: a retrospective case study series of acute thrombotic complications on stable underlying atherosclerotic disease.

BACKGROUND AND PURPOSE: Ischaemic stroke has been described in association with COVID-19. Several pathophysiological mechanisms have been suggested, i.e. prothrombotic state, cardiac injury etc. It was sought to assess the potential association between ischaemic stroke associated with SARS-CoV-2 infection and underlying atherosclerotic lesions. METHODS: A retrospective analysis of stroke related to large vessel occlusion was conducted amongst patients with SARS-CoV-2 infection and underlying mild atherosclerotic disease, between 19 March and 19 April 2020 in six different stroke centers in the Île-de France area, France. RESULTS: The median age was 52 years, median body mass index was 29.5 kg/m2 . All patients displayed previous vascular risk factors such as high blood pressure, diabetes, dyslipidemia or body mass index > 25. The delay between the first respiratory symptoms of COVID-19 and stroke was 11.5 days. At baseline, all had tandem occlusions, i.e. intracerebral and extracerebral thrombus assessed with computed tomography or magnetic resonance imaging. Cases displayed a large thrombus in the cervical carotid artery with underlying mild non-stenosing atheroma, after an etiological workup based on angio-computed tomography or magnetic resonance imaging and/or cervical echography. CONCLUSION: Our study should alert clinicians to scrutinize any new onset of ischaemic stroke during COVID-19 infection, mainly in patients with vascular risk factors or underlying atherosclerotic lesions.

Early successful reperfusion after endovascular therapy reduces malignant middle cerebral artery infarction occurrence in young patients with large diffusion-weighted imaging lesions.

BACKGROUND AND PURPOSE: Malignant middle cerebral artery infarction (MMI) is a severe complication of acute ischaemic stroke (AIS). The aim of our study was to assess whether successful reperfusion after endovascular therapy (EVT) in AIS with clinical and imaging predictors of MMI decreased its occurrence. METHODS: Data were collected between January 2014 and July 2018 in a monocentric prospective AIS registry of patients treated with EVT. Patients selected were <65 years old with severe anterior circulation AIS with a National Institutes of Health Stroke Scale score >15, baseline Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Score ≤ 6 and baseline diffusion-weighted imaging lesion volume >82 mL within 6 h of symptom onset. Successful reperfusion was defined as a Thrombolysis in Cerebral Ischemia score ≥ 2b. Occurrence of MMI was the primary endpoint. RESULTS: A total of 66 EVT-treated patients were included in our study. MMI occurred in 27 patients (41%). In unadjusted analysis, successful reperfusion was associated with fewer MMIs (31.8% vs. 65.0%; P = 0.015) and with more favorable outcome at 3 months (50% vs. 20%; P = 0.023). In multivariate analysis, successful reperfusion was associated with an adjusted odds ratio (95% confidence intervals) of 0.35 (0.10-1.12) for MMI and 2.77 (0.84-10.43) for 3-month favorable outcome occurrence. CONCLUSIONS: Early successful reperfusion performed in patients with AIS with clinical and imaging predictors of MMI was associated with decreased MMI occurrence. Reperfusion status might be considered in evaluating the need for craniectomy in patients with early predictors of MMI.

Two-layered susceptibility vessel sign is associated with biochemically quantified thrombus red blood cell content.

BACKGROUND AND PURPOSE: Better characterization of the thrombus could be useful to determine acute ischaemic stroke (AIS) aetiology and predict response to thrombolysis and endovascular therapy (EVT). To test the hypothesis that susceptibility vessel sign (SVS) on baseline magnetic resonance imaging (MRI) is related to red blood cell (RBC) content of AIS thrombi, the total haemoglobin contents (HbCs) of AIS thrombi retrieved by EVT from patients with or without SVS or two-layered SVS (TLSVS) were compared. METHODS: Baseline MRI of 84 anterior AIS patients was reviewed by neuro-radiologists blinded to clinical and biochemical data. Thrombi from these patients were retrieved by EVT and analysed for HbC by quantitative enzyme-linked immunosorbent assay and measurement of haem concentration. RESULTS: Susceptibility vessel sign and TLSVS were respectively observed in 85.7% and 50.0% of cases. The median HbC content was 253 µg/mg thrombus (interquartile range 177-333) and the median haem content was 219 µg/mg thrombus (131-264). Thrombus HbC and haem content were highly correlated with thrombus RBC content determined by flow cytometry (r = 0.94). Thrombi from patients with TLSVS weighed more [31.1 (16.5-68.3) mg vs. 17.7 (11.7-33.3) mg; P = 0.005] and had a higher HbC content [278 (221-331) µg/mg vs. 196 (139-301) µg/mg; P = 0.010] compared to thrombi from patients without TLSVS. There was no difference in thrombus weight or HbC content according to SVS status. CONCLUSIONS: Our study shows that TLSVS is significantly associated with a higher thrombus weight and RBC content, as determined by quantitative assays.

Angiographic Analysis of Natural Anastomoses between the Posterior and Anterior Cerebral Arteries in Moyamoya Disease and Syndrome.

BACKGROUND AND PURPOSE: Moyamoya disease is a chronic neurovascular steno-occlusive disease of the internal carotid artery and its main branches, associated with the development of compensatory vascular collaterals. Literature is lacking about the precise description of these compensatory vascular systems. Usually, the posterior circulation is less affected, and its vascular flow could compensate the hypoperfusion of the ICA territories. The aim of this study was to describe these natural connections between the posterior cerebral artery and the anterior cerebral artery necessary to compensate the lack of perfusion of the anterior cerebral artery territories in the Moyamoya population. MATERIALS AND METHODS: All patients treated for Moyamoya disease from 2004 to 2018 in 4 neurosurgical centers with available cerebral digital subtraction angiography were included. Forty patients (80 hemispheres) with the diagnosis of Moyamoya disease were evaluated. The presence of anastomoses between the posterior cerebral artery and the anterior cerebral artery was found in 31 hemispheres (38.7%). RESULTS: Among these 31 hemispheres presenting with posterior cerebral artery-anterior cerebral artery anastomoses, the most frequently encountered collaterals were branches from the posterior callosal artery (20%) and the posterior choroidal arteries (20%). Another possible connection found was pio-pial anastomosis between cortical branches of the posterior cerebral artery and the anterior cerebral artery (15%). We also proposed a 4-grade classification based on the competence of these anastomoses to supply retrogradely the territories of the anterior cerebral artery. CONCLUSIONS: We found 3 different types of anastomoses between the anterior and posterior circulations, with different abilities to compensate the anterior circulation. Their development depends on the perfusion needs of the territories of the anterior cerebral artery and can provide the retrograde refilling of the anterior cerebral artery branches.

Three-dimensional segmentation and symbolic representation of cerebral vessels on 3DRA images of arteriovenous malformations.

BACKGROUND: Endovascular embolization is a minimally invasive interventional method for the treatment of neurovascular pathologies such as aneurysms, arterial stenosis or arteriovenous malformations (AVMs). In this context, neuroradiologists need efficient tools for interventional planning and microcatheter embolization procedures optimization. Thus, the development of helpful methods is necessary to solve this challenging issue. METHODS: A complete pipeline aiming to assist neuroradiologists in the visualization, interpretation and exploitation of three-dimensional rotational angiographic (3DRA) images for interventions planning in case of AVM is proposed. The developed method consists of two steps. First, an automated 3D region-based segmentation of the cerebral vessels which feed and drain the AVM is performed. From this, a graph-like tree representation of these connected vessels is then built. This symbolic representation provides a vascular network modelization with hierarchical and geometrical features that helps in the understanding of the complex angioarchitecture of the AVM. RESULTS: The developed workflow achieves the segmentation of the vessels and of the malformation. It improves the 3D visualization of this complex network and highlights its three main components that are the arteries, the veins and the nidus. The symbolic representation then brings a better comprehension of the vessels angioarchitecture. It provides decomposition into topologically related vessels, offering the possibility to reduce the complexity due to the malformed vessels and also determine the optimal paths for AVM embolization during interventions planning. CONCLUSIONS: A relevant vascular network modelization has been developed that constitutes a breakthrough in the assistance of neuroradiologists for AVM endovascular embolization planning.

Endovascular Treatment for Low-Grade (Spetzler-Martin I-II) Brain Arteriovenous Malformations.

BACKGROUND AND PURPOSE: Surgical resection is usually considered as the first-line curative strategy for low-grade (Spetzler-Martin grade I-II) brain arteriovenous malformations because it has a high cure rate and low complications. The role of endovascular treatment remains to be clarified in this indication, especially after A Randomized Trial of Unruptured Brain Arteriovenous Malformations. Our objective was to assess the safety and efficacy of first-line endovascular treatment in low-grade brain arteriovenous malformation management at our institution. MATERIALS AND METHODS: Patients with low-grade brain arteriovenous malformations treated primarily with embolization in our department between January 2005 and December 2015 were retrieved from our prospectively collected registry. The primary outcome was the brain arteriovenous malformation obliteration rate, and secondary outcomes were disability or death secondary to brain arteriovenous malformation embolization assessed through modification of the modified Rankin Scale. RESULTS: Two hundred twenty-four patients completed endovascular treatment during the study period and represent our study population. Complete exclusion of brain arteriovenous malformations was achieved in 205 patients (92%), including 62.1% of brain arteriovenous malformation exclusions after a single endovascular treatment session. One patient died of a hemorrhagic complication after endovascular treatment, leading to a mortality rate of 0.4%. Twelve patients (5%) kept a permanent neurologic deficit secondary to a complication of the endovascular treatment. An overall good outcome (mRS 0-2) was reported in 179 patients (80%). CONCLUSIONS: Endovascular treatment might be a suitable alternative to surgical resection for complete exclusion of selected low-grade brain arteriovenous malformations.

Hemorrhagic transformation after stroke: inter- and intrarater agreement.

BACKGROUND AND PURPOSE: Hemorrhagic transformation (HT) is a complication of stroke that can occur spontaneously or after treatment. We aimed to assess the inter- and intrarater reliability of HT diagnosis. METHODS: Studies assessing the reliability of the European Cooperative Acute Stroke Study (ECASS) classification of HT or of the presence (yes/no) of HT were systematically reviewed. A total of 18 raters independently examined 30 post-thrombectomy computed tomography scans selected from the Aspiration versus STEnt-Retriever (ASTER) trial. They were asked whether there was HT (yes/no), what the ECASS classification of the particular scan (0/HI1/HI2/PH1/PH2) (HI indicates hemorrhagic infarctions and PH indicates parenchymal hematomas) was and whether they would prescribe an antiplatelet agent if it was otherwise indicated. Agreement was measured with Fleiss' and Cohen's κ statistics. RESULTS: The systematic review yielded four studies involving few (≤3) raters with heterogeneous results. In our 18-rater study, agreement for the presence of HT was moderate [κ = 0.55; 95% confidence interval (CI), 0.41-0.68]. Agreement for ECASS classification was only fair for all five categories, but agreement improved to substantial (κ = 0.72; 95% CI, 0.69-0.75) after dichotomizing the ECASS classification into 0/HI1/HI2/PH1 versus PH2. The inter-rater agreement for the decision to reintroduce antiplatelet therapy was moderate for all raters, but substantial among vascular neurologists (κ = 0.70; 95% CI, 0.57-0.84). CONCLUSION: The ECASS classification may involve too many categories and the diagnosis of HT may not be easily replicable, except in the presence of a large parenchymal hematoma.

Anatomic and Angiographic Analyses of Ophthalmic Artery Collaterals in Moyamoya Disease.

BACKGROUND AND PURPOSE: Moyamoya disease is a progressive neurovascular pathology defined by steno-occlusive disease of the distal internal carotid artery and associated with the development of compensatory vascular collaterals. The etiology and exact anatomy of vascular collaterals have not been extensively studied. The aim of this study was to describe the anatomy of collaterals developed between the ophthalmic artery and the anterior cerebral artery in a Moyamoya population. MATERIALS AND METHODS: All patients treated for Moyamoya disease from 2004 to 2016 in 4 neurosurgical centers with available cerebral digital subtraction angiography were included. Sixty-three cases were evaluated, and only 38 met the inclusion criteria. Two patients had a unilateral cervical internal carotid occlusion that limited analysis of ophthalmic artery collaterals to one hemisphere. This study is consequently based on the analysis of 74 cerebral hemispheres. RESULTS: Thirty-eight patients fulfilled the inclusion criteria. The most frequently encountered anastomosis between the ophthalmic artery and cerebral artery was a branch of the anterior ethmoidal artery (31.1%, 23 hemispheres). In case of proximal stenosis of the anterior cerebral artery, a collateral from the posterior ethmoidal artery could be visualized (16 hemispheres, 21.6%). One case (1.4%) of anastomosis between the lacrimal artery and the middle meningeal artery that permitted the vascularization of a middle cerebral artery territory was also noted. CONCLUSIONS: Collaterals from the ophthalmic artery are frequent in Moyamoya disease. Their development depends on the perfusion needs of the anterior cerebral artery territories. Three other systems of compensation could be present (callosal circle, leptomeningeal anastomosis, and duro-pial anastomoses).

Application of the DAWN clinical imaging mismatch and DEFUSE 3 selection criteria: benefit seems similar but restrictive volume cut-offs might omit potential responders.

BACKGROUND AND PURPOSE: An external validation of the selection criteria of diffusion-weighted imaging or computerized tomography perfusion assessment with clinical mismatch in the triage of wake-up and late-presenting strokes undergoing the Neurointervention with Trevo (DAWN) and the Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke (DEFUSE3) trials was conducted in a cohort of unknown onset stroke (UOS) patients treated with thrombectomy. METHODS: A validation cohort of UOS patients was selected from a prospectively collected thrombectomy database to match the inclusion criteria of DAWN and DEFUSE 3. Patients with an initial National Institutes of Health Stroke Scale (NIHSS) ≥10 were stratified according to the DAWN selection criteria. Patients ≤90 years old with an initial NIHSS ≥6 were stratified according to the DEFUSE 3 selection criteria. The proportions of patients with a modified Rankin Scale (mRS) ≤2 at 3 months follow-up were compared between DAWN-eligible patients and the DAWN trial thrombectomy group, and between DEFUSE 3-eligible patients and the DEFUSE 3 trial thrombectomy group. RESULTS: Of the 60/102 (59%) DAWN-eligible patients, 26 patients (43%) reached a mRS ≤2 at 3 months follow-up [versus 52/107 patients (49%) in the DAWN trial thrombectomy group; P = 0.52]. Of the 100/117 (85%) DEFUSE 3-eligible patients, 48 patients (48%) reached a mRS ≤2 at 3 months follow-up [versus 41/92 patients (45%) in the DEFUSE 3 trial thrombectomy group; P = 0.67]. Of the DAWN-ineligible and DEFUSE 3-ineligible patients who underwent thrombectomy, 38% (16/42) and 41% (7/17) of patients reached a mRS ≤2, respectively. CONCLUSION: The results of the DAWN and DEFUSE 3 trials were externally validated in a UOS cohort where the trials' selection criteria identified a similar proportion of responders to thrombectomy.

Impact of intravenous thrombolysis and emergent carotid stenting on reperfusion and clinical outcomes in patients with acute stroke with tandem lesion treated with thrombectomy: a collaborative pooled analysis.

BACKGROUND AND PURPOSE: Tandem anterior circulation lesions in the setting of acute ischemic stroke (AIS) are a complex endovascular situation that has not been specifically addressed in trials. We determined the predictors of successful reperfusion and good clinical outcome at 90 days after mechanical thrombectomy (MT) in patients with AIS with tandem lesions in a pooled collaborative study. METHODS: This was a retrospective analysis of consecutive patients presenting to 18 comprehensive stroke centers with AIS due to tandem lesion of the anterior circulation who underwent MT. RESULTS: A total of 395 patients were included. Successful reperfusion (modified thrombolysis in cerebral infarction score 2b-3) was achieved in 76.7%. At 90 days, 52.2% achieved a good outcome (modified Rankin Scale score 0-2), 13.8% suffered a parenchymal hematoma and 13.2% were dead. Lower National Institutes of Health Stroke Scale score [odds ratio (OR), 1.26; 95% confidence intervals (CI), 1.07-1.48, P = 0.004], Alberta Stroke Program Early CT Score ≥7 (OR, 2.00; 95% CI, 1.07-3.43, P = 0.011), intravenous thrombolysis (OR, 1.47; 95% CI, 1.01-2.12, P = 0.042) and stenting of the extracranial carotid lesion (OR, 1.63; 95% CI, 1.04-2;53, P = 0.030) were independently associated with successful reperfusion. Lower age (OR, 1.58; 95% CI, 1.26-1.97, P < 0.001), absence of hypercholesterolemia (OR, 1.77; 95% CI, 1.10-2.84, P = 0.018), lower National Institutes of Health Stroke Scale scores (OR, 2.04; 95% CI, 1.53-2.72, P < 0.001), Alberta Stroke Program Early CT Score ≥7 (OR, 2.75; 95% CI, 1.24-6.10, P = 0.013) and proximal middle cerebral artery occlusion (OR, 1.59; 95% CI, 1.03-2.44, P = 0.035) independently predicted a good 90-day outcome. CONCLUSIONS: Intravenous thrombolysis and emergent stenting of the extracranial carotid lesion were predictors of a successful reperfusion after MT of patients with AIS with tandem lesion of the anterior circulation.

Multicenter initial experience with the EmboTrap device in acute anterior ischemic stroke.

BACKGROUND AND PURPOSE: Mechanical thrombectomy predominantly using stent retrievers effectively restores cerebral blood flow and improves functional outcomes in patients with acute ischemic stroke. We sought to determine the safety and efficacy of mechanical thrombectomy using the EmboTrap device. MATERIALS AND METHODS: We identified 80 consecutive patients from 4 centers with acute ischemic stroke treated with EmboTrap from June 2015 to December 2016. All patients had confirmed large vessel occlusions in the anterior circulation using CT or MR angiography with salvageable tissue. We assessed baseline characteristics and treatment related parameters including onset-to-treatment time, recanalization success (mTICI 2b or greater), complications, and good clinical outcome (mRS 0 to 2). RESULTS: Successful recanalization was achieved in 72 patients (90%). When considering the use of a second thrombectomy device as failure, the EmboTrap successfully recanalized 65 patients (81%), with complete (mTICI 3) recanalization in 40 patients (50%) within 1 or 2 passes. Median procedure time (groin to recanalization) was 35 minutes (8-161 minutes). During the procedure, distal emboli in previously unaffected territories were found in 5 (6%) patients. There were 3 vasospasms (4%) and no vessel perforations. Intracranial hemorrhage on CT at day 1 was found in 18 17 (2321%) patients, none with subarachnoid hemorrhages, and 5 were symptomatic (6%). Good clinical outcome occurred in 4749/68 78 patients (6963%). CONCLUSIONS: In this multicenter retrospective study, the EmboTrap device achieved high recanalization rates, good clinical outcomes and was safe in treating acute stroke patients with large vessel occlusions.