Intracranial Vessel Occlusion Research Articles

Use of Onyx Frontier™ for intracranial stenting in stroke patients: A multicenter retrospective study.

Acute ischemic stroke (AIS) due to intracranial atherosclerotic disease (ICAD) carries a high risk of recurrence despite aggressive medical management. The aim of our study is to present our initial experience with the Onyx Frontier™ balloon-mounted drug-eluting stent (Medtronic, Santa Rosa, CA) for AIS due to ICAD. We conducted a multicenter retrospective cohort study describing the technical feasibility, safety, and performance of using the Onyx Frontier™ balloon-mounted drug-eluting stent in patients with acute intracranial vessel occlusion due to ICAD across three comprehensive stroke centers in the United States. We included 23 patients in our study (mean age 67.3 [10.7]; females: n = 13/23, 56.5%). Most patients were Black (n = 14/23, 60.9%). The most common site of vessel occlusion was the M1 branch of the middle cerebral artery (MCA) (n = 14/23, 60.9%), followed by the vertebrobasilar system (n = 5/23, 21.7%), and the internal carotid artery (n = 3/23, 13.0%). Treatment with the Onyx Frontier™ stent was associated with a final mTICI score ≥2b for 100% of patients, with no vessel perforations or distal embolization. None of the patients had any restenosis or re-treatment over a median follow-up of 3.5 months (interquartile range [IQR] 7.8). All cases required a single stent except for one, where two were deployed. Transfemoral access was used in most cases (n = 18/23, 78.3%), with one in-hospital death due to access site complication (n = 1/23, 4.3%). This is the largest multicenter cohort study demonstrating the feasibility and safety of using the Onyx Frontier™ balloon-mounted zotarolimus-eluting stent to treat symptomatic AIS due to ICAD.

Prevalence and Distribution of Intracranial Vessel Occlusion on Angiography and Its Association with Functional Outcome in Patients with Atrial Fibrillation Presenting with Ischemic Stroke.

To determine the prevalence and distribution of intracranial vessel occlusion identified on computed tomography (CT) or magnet resonance (MR) angiography and to explore its association with functional outcome in patients with atrial fibrillation (AF) and ischemic stroke. Multicenter cohort study enrolling consecutive patients with AF with imaging-confirmed ischemic stroke who underwent CT- or MR-angiography on admission (2014-2022). Multivariable regression was used to explore the association between intracranial vessel occlusion and poor functional outcome (modified Rankin Scale score 3-6) at 90 days. The analysis included 10,164 patients (median age 81.5 years, 47.8% female, median National Institutes of Health Stroke Scale score on admission 6; 14.7% on a vitamin K antagonist [VKA], 27.5% on a direct oral anticoagulant [DOAC], 57.8% not receiving oral anticoagulation). Angiography showed intracranial vessel occlusion in 5,190 patients (51.1%), affecting the anterior cerebral circulation in 87.4%. Overall, 29.2% and 29.4% of patients received thrombolysis and mechanical thrombectomy, respectively. The proportion of patients with poor functional outcome at 90 days was 60.6% and 42.7% in those with and without vessel occlusion, respectively. In multivariable analyses, vessel occlusion was associated with poor functional outcome (adjusted odds ratio [aOR]: 1.95, 95% confidence interval [CI]: 1.71-2.22) with consistent results in subgroups according to oral anticoagulation use (VKA, aOR: 1.98, 95% CI: 1.40-2.80; DOAC, aOR: 2.35, 95% CI: 1.83-3.03; none, aOR: 1.76, 95% CI: 1.49-2.09). Intracranial vessel occlusion is common in patients with AF with ischemic stroke, mainly affects the anterior circulation and is associated with poor functional outcome. ANN NEUROL 2024.

The Role of Systemic Inflammation in the Pathogenesis of Spontaneous Intracranial Hemorrhage in the Presence or Absence of Effective Cerebral Blood Flow.

Background: Spontaneous intracerebral hemorrhage (ICH) is one of the leading causes of mortality in intensive care units. The role of systemic hyperintense inflammation (SHI) in the pathogenesis of critical complications of ICH remains a poorly understood problem. There is a specific variant of severe ICH associated with increased intracranial pressure and occlusion of intracranial vessels, defined as ineffective cerebral blood flow (IECBF). Methods: To evaluate the role of SHI in the pathogenesis of severe (comatose) ICH in a dynamic comparison of patients with IECBF (n-26) and without IECBF (n-52). The SHI integral score criterion (SI scale) was used, including certain values of plasma concentrations of IL-6, IL-8, IL-10; TNF-α, PCT, cortisol, myoglobin, troponin I, D-dimer, and, additionally, SOFA scale values. Blood levels of ACTH and neuron-specific enolase (NSE) were also assessed. Results: Twenty-eight-day mortality in severe ICH reached 84.6% (without IECBF) and 96.2% (with IECBF). Clear signs of SHI were detected in 61.5%/87.8% (without IECBF) and 0.0%/8.7% (with IECBF) within 1-3/5-8 days from the onset of ICH manifestation. The lower probability of developing SHI in the IECBF group was associated with low blood NSE concentrations. Conclusions: The development of SHI in ICH is pathogenetically related to the permeability of the blood-brain barrier for tissue breakdown products and other neuroinflammatory factors.

Safety and efficacy of stent retrievers plus contact aspiration in patients with acute ischaemic anterior circulation stroke and positive susceptibility vessel sign in France (VECTOR): a randomised, single-blind trial

Positive susceptibility vessel sign (SVS) in patients with acute ischaemic stroke has been associated with friable red blood cell-rich clots and more effective recanalisation using stent retrievers versus contact aspiration. We compared the safety and efficacy of stent retrievers plus contact aspiration (combined technique) versus contact aspiration alone as the first-line thrombectomy technique in patients with acute ischaemic anterior circulation stroke and SVS-positive occlusions. Adaptive Endovascular Strategy to the Clot MRI in Large Intracranial Vessel Occlusion (VECTOR) was a prospective, randomised, open-label study with blinded evaluation. Patients with SVS-positive anterior circulation occlusions on pretreatment MRI and arterial puncture within 24 h of symptom onset were enrolled from 22 centres in France. A centralised web-based method was used by interventional neuroradiologists for dynamic randomisation by minimisation. Patients were randomly assigned 1:1 to the combined technique or contact aspiration alone. The primary outcome was expanded Thrombolysis in Cerebral Infarction (eTICI) grade 2c or 3 reperfusion after three or fewer passes on post-treatment angiogram, adjudicated by a blinded independent central imaging core laboratory. The intention-to-treat population was used to assess the primary and secondary outcomes. This trial is registered with ClinicalTrials.gov (NCT04139486) and is complete. Between Nov 26, 2019, and Feb 14, 2022, 526 patients were enrolled, of whom 521 constituted the intention-to-treat population (combined technique, n=263; contact aspiration alone, n=258). The median age of participants was 74·9 years (IQR 64·4-83·3); 284 (55%) were female and 237 (45%) male. The primary outcome did not differ significantly between groups (152 [58%] of 263 patients for the combined technique vs 135 [52%] of 258 for contact aspiration; odds ratio [OR] 1·27; 95% CI 0·88-1·83; p=0·19). Procedure-related adverse events occurred in 32 (12%) of 263 patients in the combined technique group and 27 (11%) of 257 in the contact aspiration group (OR 1·14; 0·65-2·00; p=0·65). The most common adverse event was intracerebral haemorrhage (146 [56%] of 259 patients for the combined technique vs 123 [49%] of 251 for contact aspiration; OR 1·32; 0·91-1·90; p=0·13). All-cause mortality at 3 months occurred in 57 (23%) of 251 patients in the combined technique group and 48 (19%) of 247 in the contact aspiration group (OR 1·19; 0·76-1·86; p=0·45), none of which was treatment-related. The results of the VECTOR trial do not show superiority of the combined stent retriever plus contact aspiration technique over contact aspiration alone in patients with SVS-positive occlusion with respect to achieving eTICI 2c-3 within three passes. These findings support the use of either the combined technique or contact aspiration alone as the initial thrombectomy strategy in patients with acute anterior circulation stroke with SVS on pretreatment MRI. Cerenovus.

Nimodipine as Vasodilator in Guide Catheter Flush to Prevent Vasospasm During Endovascular Stroke Treatment.

The clinical importance and management of vasospasm as acomplication during endovascular stroke treatment (EVT) has not been well studied. We sought to investigate the effect of adding nimodipine to the guiding catheter flush (GCF) to prevent vasospasm during EVT. This is asingle-center retrospective analysis including patients with EVT (stent-retriever and/or distal aspiration) treated for anterior or posterior circulation intracranial vessel occlusion from January 2018 to June 2023. Exclusion criteria were intracranial or extracranial stenosis, intra-arterial alteplase, patient age over 80years. Study groups were patients with (nimo+) and without (nimo-) nimodipine in the GCF. They were compared for occurrence of vasospasm as primary endpoint and clinical outcome in univariate analysis. 477 patients were included in the analysis (nimo+ n = 94 vs. nimo- n = 383). Nimo+ patients experienced less vasospasm during EVT (e.g. vasospasm in target vessel n(%): nimo- = 113 (29.6) vs. nimo+ = 9(9.6), p < 0.001; extracranial vasospasm, n(%): nimo- = 68 (17.8) vs. nimo+ = 7(7.4), p = 0.017). Patients of the two study groups had acomparable clinical outcome (90day mRS, median (IQR): 3(1-6) for both groups, p = 0.896). In general, patients with anterior circulation target vessel occlusion (TVO) experienced more vasospasm (anterior circ. TVO 38.7% vs. posterior circ. 7.5%, p = 0.006). Prophylactic adding of nimodipine reduces the risk of vasospasm during EVT without affecting the clinical outcome. Patients with anterior circulation TVO experienced more vasospasm compared to posterior circulation TVO.

Combined intravenous and intra-arterial thrombolysis in hyperacute cerebral ischemia without significant corresponding vascular occlusion/stenosis: A Preliminary investigation

ObjectiveIn this study, we assessed the efficacy and safety of various thrombolytic treatment protocols in patients with hyperacute cerebral infarction. MethodsPatients diagnosed with acute ischemic stroke within 6 h of symptom onset and with brain computer tomography angiography confirming the absence of major vessel stenosis or occlusion were eligible for this study. The enrolled patients were subsequently randomized into two groups: all the groups received the standard intravenous thrombolysis treatment with rt-PA (0.9 mg/kg), and the experimental group underwent sequential intra-arterial thrombolysis treatment with alteplase (0.3 mg/kg, with a maximum dose of 22 mg), administered directly into the target vessel via a microcatheter. Both groups were closely monitored for changes in their National Institutes of Health Stroke Scale (NIHSS) score, modified Rankin scale score, hemorrhage rate, all-cause mortality rate, and the rate of favorable outcomes at 90 ± 7 days. ResultsNinety-four participants were enrolled in this study, with both the control and experimental groups initiating intravenous injection of rt-PA at a median time of 29 min. For the experimental group, the median time for arterial puncture was 123 min. Baseline data for both groups were similar (P > 0.05). Hemorrhagic transformation occurred in 24.47 % (23 patients), with a lower intracranial hemorrhage rate observed in the experimental group compared to the control group (15.2 % vs 33.3 %, P < 0.05). Asymptomatic hemorrhage rates were 8.7 % for the experimental group and 12.5 % for the control group, with no hemorrhage detected in other locations. Post-treatment median NIHSS scores were lower in the experimental group than in the control group (7 vs 9, P < 0.05), but short-term NIHSS scores were similar (P > 0.05). A higher proportion of patients in the experimental group achieved favorable outcomes compared to the control group (87.0 % vs 43.8 %, P < 0.05). ConclusionIn patients with acute ischemic stroke with an onset time of ≤6 h and no major intracranial vessel occlusion, combining rt-PA intravenous thrombolysis with intra-arterial thrombolysis via a microcatheter might yield superior functional outcomes.

Traditional Thrombus Composition and Related Endovascular Outcomes: Catching up with the Recent Evidence.

Endovascular thrombectomy is the primary treatment for acute intracranial vessel occlusion and significantly improves recanalization success rate. However, achieving optimal recanalization remains a challenge. The histopathological components of thrombus composition play a crucial role in determining endovascular outcomes. This review aimed to consolidate the recent evidence on the impact of thrombus composition on mechanical properties and endovascular outcomes. The relationship between thrombus composition and mechanical properties was significant, with fibrin and/or platelet-rich thrombi being stiff, tough, elastic, and less deformable; fibrin-rich thrombi were sticky and had higher friction with the vessel wall. Erythrocyte composition was positively associated with successful recanalization, whereas lower platelet composition was associated with specific outcomes, such as the first-pass effect and complete recanalization. The number of thrombectomy device passes was possibly related to erythrocyte, platelet, and fibrin composition, with a smaller number of passes associated with erythrocyte-rich thrombi. Procedural time was consistently related to thrombus composition, with shorter times observed for erythrocyte-rich thrombi. The relationship between thrombus composition and secondary embolism remains inconclusive. Understanding the role of thrombus composition in endovascular outcomes is crucial to optimize stroke treatment. Although evidence suggests a link between thrombus composition and mechanical properties, further research is needed to establish stronger correlations and to reduce study variations. Exploring non-traditional thrombus components such as leukocytes and neutrophil extracellular traps is vital. Thrombus imaging could provide a practical solution for predicting thrombus composition before endovascular procedures. This review highlights the importance of thrombus composition for enhancing endovascular stroke treatment strategies.

LVONet: automatic classification model for large vessel occlusion based on the difference information between left and right hemispheres.

Objective.Stroke is a highly lethal condition, with intracranial vessel occlusion being one of its primary causes. Intracranial vessel occlusion can typically be categorized into four types, each requiring different intervention measures. Therefore, the automatic and accurate classification of intracranial vessel occlusions holds significant clinical importance for assessing vessel occlusion conditions. However, due to the visual similarities in shape and size among different vessels and variations in the degree of vessel occlusion, the automated classification of intracranial vessel occlusions remains a challenging task. Our study proposes an automatic classification model for large vessel occlusion (LVO) based on the difference information between the left and right hemispheres.Approach.Our approach is as follows. We first introduce a dual-branch attention module to learn long-range dependencies through spatial and channel attention, guiding the model to focus on vessel-specific features. Subsequently, based on the symmetry of vessel distribution, we design a differential information classification module to dynamically learn and fuse the differential information of vessel features between the two hemispheres, enhancing the sensitivity of the classification model to occluded vessels. To optimize the feature differential information among similar vessels, we further propose a novel cooperative learning loss function to minimize changes within classes and similarities between classes.Main results.We evaluate our proposed model on an intracranial LVO data set. Compared to state-of-the-art deep learning models, our model performs optimally, achieving a classification sensitivity of 93.73%, precision of 83.33%, accuracy of 89.91% and Macro-F1 score of 87.13%.Significance.This method can adaptively focus on occluded vessel regions and effectively train in scenarios with high inter-class similarity and intra-class variability, thereby improving the performance of LVO classification.

Thrombus migration in emergent M1 middle cerebral artery occlusion

Background and purposeThrombus migration (TM) is a well-established phenomenon in patients with intracranial vessel occlusion, particularly in those who receive alteplase. However, the relationship between TM, reperfusion success, and clinic-radiological outcomes is still being determined. This study aimed to describe the various outcomes in the event of TM in patients with M1 middle cerebral artery (M1 MCA) occlusion. Materials and MethodsThe study involved a retrospective analysis of patients undergoing endovascular thrombectomy (EVT) due to M1 MCA occlusion from two tertiary centers between January 2015 and December 2020. The proximal positions of thrombi were measured using a curve tool on CT or MR angiography before EVT. Subsequently, measurements were taken on angiographic imaging. Patients were grouped based on the amount of difference between the two measurements: growth (≤ - 10 mm), stability (> −10 mm and ≤ 10 mm), migration (> 10 mm), and resolution. ResultsA total of 463 patients (266 [57%] females, median 76 [interquartile range IQR: 65–83] years) were analyzed. Of them, 106 (22.8%) expressed any degree of TM. In multivariate ordinal regression analysis, the alteplase was significantly associated with TM (t = 2.192, p = 0.028), as was the greater interval from first imaging to angiography (t = 2.574, p = 0.010). In multivariate logistical regression analysis, the good clinical outcome measured by the modified Rankin scale (0−2) was not associated with TM status. ConclusionsThrombus migration within the M1 MCA segment occurs in almost a quarter of patients, is associated with alteplase administration, and is mainly irrelevant to radiological and clinical outcome.

Intravenous Thrombolysis Before Endovascular Treatment in Posterior Circulation Occlusions: A MR CLEAN Registry Study.

The effectiveness of intravenous thrombolysis (IVT) before endovascular treatment (EVT) has been investigated in randomized trials and meta-analyses. These studies mainly concerned anterior circulation occlusions. We aimed to investigate clinical, technical, and safety outcomes of IVT before EVT in posterior circulation occlusions in a nationwide registry. Patients were included from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands), a nationwide, prospective, multicenter registry of patients with acute ischemic stroke due to a large intracranial vessel occlusion receiving EVT between 2014 and 2019. All patients with a posterior circulation occlusion were included. Primary outcome was a shift toward better functional outcome on the modified Rankin Scale at 90 days. Secondary outcomes were favorable functional outcome (modified Rankin Scale scores, 0-3), occurrence of symptomatic intracranial hemorrhages, successful reperfusion (extended Thrombolysis in Cerebral Ischemia ≥2B), first-attempt successful reperfusion, and mortality at 90 days. Regression analyses with adjustments based on univariable analyses and literature were applied. A total of 248 patients were included, who received either IVT (n=125) or no IVT (n=123) before EVT. Results show no differences in a shift on the modified Rankin Scale (adjusted common odds ratio, 1.04 [95% CI, 0.61-1.76]). Although symptomatic intracranial hemorrhages occurred more often in the IVT group (4.8% versus 2.4%), regression analysis did not show a significant difference (adjusted odds ratio, 1.65 [95% CI, 0.33-8.35]). Successful reperfusion, favorable functional outcome, first-attempt successful reperfusion, and mortality did not differ between patients treated with and without IVT. We found no significant differences in clinical, technical, and safety outcomes between patients with a large vessel occlusion in the posterior circulation treated with or without IVT before EVT. Our results are in line with the literature on the anterior circulation.

Outcome of endovascular stroke therapy in a large mandatory stroke-registry

BackgroundEndovascular stroke treatment (EST) has become the standard treatment for patients with stroke due to large vessel occlusion, especially in earlier time windows. Only few data from population-based registries on effectiveness of EST have been published.MethodsBaden–Wuerttemberg is the third largest state in Germany in terms of area and population and has a structured stroke concept since 1998 which includes mandatory collection of quality assurance data. In 2018 and 2019, 3820 of 39,168 ischemic stroke patients (9.8%) were treated by EST (age median 78 y, NIHSS median 14). We analyzed the clinical outcome of these patients determined with the modified Rankin Scale (mRS) at discharge from the hospital or with the initiation of palliative therapy using logistic regression analysis with adjustment for the mRS at admission, additive IVT, age, and NIHSS.ResultsThe probability of an excellent clinical outcome (mRS 0 or 1 at discharge) and for a good clinical outcome (mRS 0–2) were significantly higher in EST-patients (odds-ratio (OR) 1.27; 95% confidence interval (95% CI) 1.13–1.43, and OR of 1.15 (95% CI 1.04–1.28). Also, the regression model showed an advantage for EST-patients with less frequent ‘decision for palliative care’ (OR 0.87; 95% CI 0.78–0.98). Sensitivity analysis adjusting for intracranial vessel occlusion as further factor showed similar results.ConclusionOur data suggest that EST can be of benefit also for an area-wide unselected stroke population, in a large German federal state with sometimes long distance to the next thrombectomy center.

Abstract 221: EARLY EXPERIENCE OF EMBOGUARD BALLOON GUIDE CATHETER IN LARGE VESSEL OCCLUSION THROMBECTOMY

Introduction Endovascular thrombectomy (EVT) is the standard of care in acute ischemic stroke secondary to large vessel occlusion in selective patients within the first 24 hours. With the evolving technology and newer generation of catheters and devices, the interest in improving the technical and procedural factors that can help better the recanalization success, clinical outcomes, and efficiency is ever‐growing. Proximal flow arrest with balloon guide catheters (BGC) has been shown to optimize revascularization success and functional outcome in stroke EVT. We aim to evaluate the performance of the Emboguard BGC (Cerenovus, Irvine, CA, USA) in anterior circulation large vessel occlusion (LVO) acute ischemic strokes. Methods A prospectively maintained EVT database was reviewed for 12 months between May 2022 to May 2023 to identify all patients at our institution with intracranial vessel occlusion who underwent EVT using Emboguard BGC. Included patients were ≥18 years with large‐vessel occlusion who presented within 24 hours of time from last‐known‐well and had baseline National Institutes of Health Stroke Scale (NIHSS) score ≥ 6. Non‐dominant M2, M3, and A2 occlusions were excluded. We collected baseline demographic, clinical, and radiographic characteristics including age, sex, co‐morbidities, baseline NIHSS score, baseline modified Rankin Score (mRS), ASPECTS score, site of occlusion, imaging at our site, and use of intravenous and/or intra‐arterial thrombolytics. Outcomes included complications, NIHSS at discharge, final modified TICI (thrombolysis in cerebral ischemia) scores including the first‐pass effect (FPE, defined as mTICI 2c/3 after first pass), modified‐FPE (defined as, mTICI 2b‐3 after first pass), symptomatic intracranial hemorrhage (SITS‐MOST definition), and death at discharge. Data were analyzed using descriptive statistics, with frequency/percent for qualitative data and median/ interquartile range (IQR) for quantitative data. Results A total of 57 patients underwent EVT using Emboguard BGC. Among them, 54.4% were female and the median age was 72 years [IQR 66‐80]. Most of the patients had MCA occlusion (68.4% with 50.9% M1 and dominant/co‐dominant M2s 17.5%) with median ASPECTS 9 [IQR 8‐10]). About one‐third of our patients received intravenous thrombolytics. Following EVT, successful recanalization defined as modified TICI (thrombolysis in cerebral ischemia) scores of 2b/3 was achieved in 56 cases (98.2%) with 1 being the median number of passes (IQR 1‐2). The first pass effect (defined as one pass with mTICI of 2c/3) was achieved in 45.6% of cases. The median National Institutes of Health Stroke Scale (NIHSS) reduced significantly from 16 (IQR 12‐22) at baseline to 4 (IQR 1.5–12) at discharge (Table). Symptomatic intracranial hemorrhage was reported in 6 cases (10.5%), death at discharge was reported in 9 cases (15.8%), and access site complications were reported in 3 cases (5.3%). Conclusion Emboguard BGC showed promising results evident by a high rate of FPE, smaller number of EVT passes and improved recanalization rates with reasonable safety profile. Comparative prospective studies are needed to confirm these results.

Abstract 224: Morphological characteristics of carotid webs associated with stroke risk and clot burden

Introduction Carotid webs (CaWs) have been established as an ischemic stroke etiology although lesion characteristics that may lead to increased stroke risk are still uncertain (1). We aim to evaluate the associations between CaW morphological features evaluated via computed tomography angiography (CTA) with clinical and radiological variables. Methods This is a retrospective analysis of a prospectively collected mechanical thrombectomy database. Individuals that presented with a suspected symptomatic CaW since July 2014 were selected after appropriate workup. The database included symptomatic CaW, asymptomatic CaW contralateral to the symptomatic side in case of bilateral lesions, and incidentally identified CaW (asymptomatic patients). We recorded the following CaW variables (Figure 1): length, base, thickness, caudal/middle/cranial angles in relationship to the vessel axis, area as well as perimeter of the pocket. We used mixed‐effects models to compare measurements between symptomatic and asymptomatic webs in the complete sample and paired Wilcoxon tests to compare webs of individuals with contralateral, symptom‐discordant CaW. Measurements were evaluated against clot burden via Poisson regression.a Results 118 webs (85 symptomatic and 33 asymptomatic) from 98 stroke patients were included. Median [IQR] for age was 52[42‐58] years old, 69.0% were female, 68.4% presented with a single symptomatic web, 18.4% had both a symptomatic and an asymptomatic web, 11.2% had only an asymptomatic web, whereas 2.0% had bilaterally asymptomatic webs. Symptomatic CaW were significantly larger in length (2.5mm[2.1‐3.5] vs. 2.2mm[1.7‐2.7];p=0.004) and pocket area (1.5mm²[0.9‐2.6] vs. 0.9 mm²[0.2‐1.3];p=0.007) compared to the asymptomatic lesions. The cranial angle was more acute for symptomatic CaW (66.9°[57.1°‐78.4°] vs. 76.2°[66.9°‐88.7°];p=0.046). No other significant associations were noted. Among the 18 patients who were analyzed for contralateral/symptom‐discordant webs, symptomatic CaW also showed more extensive lengths (2.9mm[2.3‐4.0] vs. 2.2mm[1.6‐3.1];p=0.009) but less acute rostral angles (33.1°[25.3°‐43.5°] vs. 27.9°[16.8°‐35.9°]) than their asymptomatic counterparts. Among symptomatic webs, clot burden was not significantly associated with base, length, thickness, perimeter or pocket area. Nevertheless, each 15° increase in the angle within the pocket was associated with a 1.1‐fold increase in clot burden (exp(β) = 1.1(95%CI1.0‐1.2), p = 0.044) for each 15° increase), with more obtuse angles indicating a higher intracranial vessel occlusion thrombus load. Conclusion Symptomatic carotid webs displayed larger lengths and pocket areas as compared to asymptomatic lesions. The angles that determine pocket area and degree of stenosis differed between symptomatic and asymptomatic webs.

Evaluation of effectiveness and safety of the multizone NeVaTM stent retriever for mechanical thrombectomy in ischemic stroke

PurposeThis study aimed to evaluate the effectiveness and safety of the NeVaTM stent retriever as first- and second-line device for mechanical thrombectomy in acute ischemic stroke.MethodsIn this retrospective single-center study, all consecutive patients that underwent mechanical thrombectomy with NeVaTM stent retriever as first- or second-line device due to intracranial vessel occlusion with acute ischemic stroke between March and November 2022 were included.ResultsThirty-nine patients (m=18, f=21) with a mean age of 69.9 ± 13.3 years were treated with the NeVaTM stent retriever. NeVaTM stent retriever was used as first-line device in 24 (61.5%) of patients and in 15 (38.5%) as second-line device. First-pass rate (≥mTICI 2c) of NeVaTM stent retriever was both 66.7% when used as first- or second-line device. Final recanalization rate including rescue strategies was 92.3% for ≥mTICI2c and 94.9% for ≥mTICI2b. No device-related minor or major adverse events were observed. A hemorrhage was detected in 33.3% of patients at 24h post-thrombectomy dual-energy CT, of which none was classified as symptomatic intracerebral hemorrhage. NIHSS and mRS improved significantly at discharge compared to admission (p<0.05).ConclusionThe NeVaTM stent retriever has a high effectivity and good safety profile as first- and second-line device for mechanical thrombectomy in acute ischemic stroke.

Automated Intracranial Clot Detection: A Promising Tool for Vascular Occlusion Detection in Non-Enhanced CT.

(1) Background: to test the diagnostic performance of a fully convolutional neural network-based software prototype for clot detection in intracranial arteries using non-enhanced computed tomography (NECT) imaging data. (2) Methods: we retrospectively identified 85 patients with stroke imaging and one intracranial vessel occlusion. An automated clot detection prototype computed clot location, clot length, and clot volume in NECT scans. Clot detection rates were compared to the visual assessment of the hyperdense artery sign by two neuroradiologists. CT angiography (CTA) was used as the ground truth. Additionally, NIHSS, ASPECTS, type of therapy, and TOAST were registered to assess the relationship between clinical parameters, image results, and chosen therapy. (3) Results: the overall detection rate of the software was 66%, while the human readers had lower rates of 46% and 24%, respectively. Clot detection rates of the automated software were best in the proximal middle cerebral artery (MCA) and the intracranial carotid artery (ICA) with 88-92% followed by the more distal MCA and basilar artery with 67-69%. There was a high correlation between greater clot length and interventional thrombectomy and between smaller clot length and rather conservative treatment. (4) Conclusions: the automated clot detection prototype has the potential to detect intracranial arterial thromboembolism in NECT images, particularly in the ICA and MCA. Thus, it could support radiologists in emergency settings to speed up the diagnosis of acute ischemic stroke, especially in settings where CTA is not available.

Diagnosis and management of tandem occlusion in acute ischemic stroke

Approximately 20–30% of patients with acute ischemic stroke, caused by large intracranial vessel occlusion, have a tandem lesion, defined as simultaneous presence of high-grade stenosis or occlusion of the cervical internal carotid artery and thromboembolic occlusion of the intracranial terminal internal carotid artery or its branches, usually the middle cerebral artery. Patients with tandem lesions have usually worse outcomes than patients with single intracranial occlusions, and intravenous thrombolysis is less effective in these patients. Although endovascular thrombectomy is currently a cornerstone therapy in the management of acute ischemic stroke due to large vessel occlusion, the optimal management of extracranial carotid lesions in tandem occlusion remains controversial. Acute placement of a stent in the cervical carotid artery lesion is the most used therapeutic strategy compared with stented balloon angioplasty and thrombectomy alone without carotid artery revascularization; however, treatment strategies in these patients are often more complex than with single occlusion, so treatment decisions can change based on clinical and technical considerations. The aim of this review is to analyze the results of different studies and trials, investigating the periprocedural neurointerventional management of patients with tandem lesions and the safety, efficacy of the different technical strategies available as well as their impact on the clinical outcome in these patients, to strengthen current recommendations and thus optimize patient care.

Hemodynamic Characteristics of Intracranial Atherosclerotic Stenosis: A Pilot Study of Contrast Enhancement Time-Density Curves Based on Regions of Interest.

The present study aimed to analyze the hemodynamic characteristics of occluded vessels responsible for acute ischemic stroke and to diagnose the occlusion types. Multimodal computed tomography (CT) was used to accurately identify the range of occlusion of large intracranial vessels. Regions of interest (ROI 1-3 ) were manually delineated at sites 2 mm away from the proximal, middle, and distal portions of each occlusion, generating 3 contrast enhancement time-density curves. The peak CT attenuation values, or Hounsfield units (H 1-3 ), and time-to-peak values (T 1-3 ) were extracted from each curve. H 0 and T 0 of the time-density curve, based on ROI 0 of the automatically recognized input artery, were used as the baseline values with which the odds ratios of each parameter, H 1-3/0 and T 1-3/0 , were obtained. The present study aimed to establish prediction models for intracranial atherosclerotic stenosis (ICAS) based on each ROI's time-density curve. Among the 33 acutely occluded intracranial vessels, 10 were found to have ICAS, whereas 23 did not, based on the diagnostic criteria. Significant differences were observed in patient sex, neutrophil-to-lymphocyte ratio upon admission, Alberta Stroke Program Early CT Score 24-48 hours after reperfusion therapy, and H 1/0 , H 3/0 , and T 3/0 between the ICAS and non-ICAS groups ( P < 0.05). The prediction model (model 3) based on the ROI 3 time-density curve showed the best performance for the diagnosis of ICAS (area under the curve, 0.944; 95% confidence interval, 0.854-1.000). The prediction models based on ROI 1 (model 1) and ROI 2 (model 2) showed moderate diagnostic performance (area under the curve, 0.817 vs 0.822, respectively). The best visualization for proximal occlusions was in the first phase (arterial phase) of multiphase CT angiography, and in the second phase (early venous phase) for distal occlusions. The contrast enhancement time-density curves of the ROIs at all evaluated portions of the acute ischemic stroke occlusions provided a visual display of the blood flow characteristics of the responsible vessels. The time-density curve of the ROI placed 2 mm from the distal occlusion was a combined effect of residual blood flow and collateral establishment, thus providing good performance for the diagnosis of ICAS.

Tissue Outcome Prediction in Patients with Proximal Vessel Occlusion and Mechanical Thrombectomy Using Logistic Models

Perfusion CT is established to aid selection of patients with proximal intracranial vessel occlusion for thrombectomy in the extended time window. Selection is mostly based on simple thresholding of perfusion parameter maps, which, however, does not exploit the full information hidden in the high-dimensional perfusion data. We implemented a multiparametric mass-univariate logistic model to predict tissue outcome based on data from 405 stroke patients with acute proximal vessel occlusion in the anterior circulation who underwent mechanical thrombectomy. Input parameters were acute multimodal CT imaging (perfusion, angiography, and non-contrast) as well as basic demographic and clinical parameters. The model was trained with the knowledge of recanalization status and final infarct localization. We found that perfusion parameter maps (CBF, CBV, and Tmax) were sufficient for tissue outcome prediction. Compared with single-parameter thresholding-based models, our logistic model had comparable volumetric accuracy, but was superior with respect to topographical accuracy (AUC of receiver operating characteristic). We also found higher spatial accuracy (Dice index) in an independent internal but not external cross-validation. Our results highlight the value of perfusion data compared with non-contrast CT, CT angiography and clinical information for tissue outcome-prediction. Multiparametric logistic prediction has high potential to outperform the single-parameter thresholding-based approach. In the future, the combination of tissue and functional outcome prediction might provide an individual biomarker for the benefit from mechanical thrombectomy in acute stroke care.

Prediction of underlying atrial fibrillation in patients with a cryptogenic stroke: results from the NOR-FIB Study

BackgroundAtrial fibrillation (AF) detection and treatment are key elements to reduce recurrence risk in cryptogenic stroke (CS) with underlying arrhythmia. The purpose of the present study was to assess the predictors of AF in CS and the utility of existing AF-predicting scores in The Nordic Atrial Fibrillation and Stroke (NOR-FIB) Study.MethodThe NOR-FIB study was an international prospective observational multicenter study designed to detect and quantify AF in CS and cryptogenic transient ischaemic attack (TIA) patients monitored by the insertable cardiac monitor (ICM), and to identify AF-predicting biomarkers. The utility of the following AF-predicting scores was tested: AS5F, Brown ESUS-AF, CHA2DS2-VASc, CHASE-LESS, HATCH, HAVOC, STAF and SURF.ResultsIn univariate analyses increasing age, hypertension, left ventricle hypertrophy, dyslipidaemia, antiarrhythmic drugs usage, valvular heart disease, and neuroimaging findings of stroke due to intracranial vessel occlusions and previous ischemic lesions were associated with a higher likelihood of detected AF. In multivariate analysis, age was the only independent predictor of AF. All the AF-predicting scores showed significantly higher score levels for AF than non-AF patients. The STAF and the SURF scores provided the highest sensitivity and negative predictive values, while the AS5F and SURF reached an area under the receiver operating curve (AUC) > 0.7.ConclusionClinical risk scores may guide a personalized evaluation approach in CS patients. Increasing awareness of the usage of available AF-predicting scores may optimize the arrhythmia detection pathway in stroke units.

Endovascular treatment of acute ischemic stroke with a fully radiopaque retriever: A randomized controlled trial.

The Neurohawk retriever is a new fully radiopaque retriever. A randomized controlled non-inferiority trial was conducted to compare the Neurohawk and the Solitaire FR in terms of safety and efficacy. In order to evaluate the efficacy and safety of endovascular treatment in acute ischemic stroke (AIS) caused by intracranial atherosclerotic disease (ICAD) larger vessel occlusion (LVO), a sub-analysis was performed. Acute ischemic stroke patients aged 18-80 years with LVO in the anterior circulation were randomly assigned to undergo thrombectomy with either the Neurohawk or the Solitaire FR. The primary efficacy endpoint was successful reperfusion (mTICI 2b-3) rate by the allocated retriever. A relevant non-inferiority margin was 12.5%. Safety outcomes were symptomatic intracranial hemorrhage (sICH) and all-cause mortality within 90 days. Secondary endpoints included first-pass effect (FPE), modified FPE, and favorable outcomes at 90 days. In subgroup analysis, the patients were divided into the ICAD group and non-ICAD group according to etiology, and baseline characteristics, angiographic, and clinical outcomes were compared. A total of 232 patients were involved in this analysis (115 patients in the Neurohawk group and 117 in the Solitaire group). The rates of successful reperfusion with the allocated retriever were 88.70% in the Neurohawk group and 90.60% in the Solitaire group (95%CI of the difference, -9.74% to 5.94%; p = 0.867). There were similar results in FPE and mFPE in both groups. The rate of sICH seemed higher in the Solitaire group (13.16% vs. 7.02%, p = 0.124). All-cause mortality and favorable outcome rates were comparable as well. In subgroup analysis, 58 patients were assigned to the ICAD group and the remaining 174 to the non-ICAD group. The final successful reperfusion and favorable outcome rates showed no statistically significant differences in two groups. Mortality within 90 days was relatively lower in the ICAD group (6.90% vs. 17.24%; p = 0.054). The Neurohawk retriever is non-inferior to the Solitaire FR in the mechanical thrombectomy of large vessel occlusion-acute ischemic stroke (LVO-AIS). The sub-analysis suggested that endovascular treatment including thrombectomy with the retriever and essential rescue angioplasty is effective and safe in AIS patients with intracranial atherosclerotic disease-larger vessel occlusion (ICAD-LVO). https://clinicaltrials.gov/ct2/show/NCT04995757, number: NCT04995757.