Stroke: Vascular and Interventional Neurology

Background: Even for experienced operators, endovascular treatment of unruptured intracranial aneurysms involves intraoperative uncertainty that may lead to adjustments in strategy, prolong the procedure, and potentially cause inefficiency and device waste. This study aimed to evaluate whether pre-procedural testing (PPT) of endovascular treatment using patient-specific models was associated with increased operator confidence and perceived clinical utility, including improvements in procedural efficiency and reduced resource waste. Methods: We enrolled a cohort of patients who underwent PPT before endovascular treatment for complex unruptured intracranial aneurysms and compared their outcomes with a control group treated without PPT. The primary outcome was the Training Fidelity Score, a composite of three operator-reported Likert items defined a priori. Secondary outcomes included perceived clinical utility, intraoperative strategy changes, procedural time, radiation exposure, device waste and safety. Results: A total of 85 patients met the inclusion criteria (PPT=40; control=45). The Training Fidelity Score was high across the PPT group (median, 4.33/5). Perceived clinical utility was high and further increased significantly after the procedure. A significant reduction was observed in intraoperative strategy changes, with no changes recorded in the PPT group, compared to 6/45 in the control group (RR 0.09; p=0.027). Reductions in treatment time, radiation exposure and device waste were also noted. Conclusion: PPT using patient-specific models was associated with increased operator confidence, fewer intraoperative strategy changes, improved procedural efficiency, and reduced device waste without compromising safety. These findings support its use in pre-interventional preparation, but require prospective multicenter validation.

IntroductionPopliteal artery aneurysms (PAAs) are the most common peripheral arterial aneurysm and carry substantial risks of limb loss. Both open and endovascular repair are widely used, yet optimal patient selection remains uncertain. We evaluated institutional operative practices and examined associations between aneurysm morphology, procedural approach, and major adverse limb events (MALE). MethodsWe conducted a retrospective cohort study at a tertiary care center to identify patients with PAAs from 2008-2022. Chart review confirmed aneurysm presence and captured demographics, comorbidities, medications, aneurysm characteristics, and operative details. Cox proportional hazards models were used to evaluate time to MALE defined as reintervention or amputation. ResultsAmong 330 PAAs, median follow-up was 7.4 months (IQR 3.4-12.7). Open repair comprised 79% (250/330), most often a medial approach (75%, 187/250) with autologous vein conduit (65%, 162/250). Open-repair patients were younger than endovascular (69 vs 74 years; p=0.006) with similar cardiovascular profiles. Indications differed by approach, with aneurysm size >20 mm most common for open repair (35.2%, 87/250) and mural thrombus most common for endovascular repair (33.3%, 24/80). MALE occurred in 30.3% (100/330). In univariate analyses, clopidogrel use was associated with increased MALE risk (HR 1.74, 95% CI 1.17-2.59; p=0.006), while descending aortic aneurysm was associated with decreased risk (HR 0.47, 95% CI 0.23-0.92; p=0.029). Operative approach, aneurysm diameter, and thrombus burden were not associated with MALE, and findings were unchanged after multivariable adjustment. ConclusionsMALE risk was comparable across operative strategies and aneurysm morphologies, suggesting that aneurysm size and thrombus burden alone should not preclude consideration of either open or endovascular repair.

ObjectiveTo define contemporary medium and long term survival and durability outcomes after elective fenestrated and branched endovascular aortic repair (F/BEVAR) for complex abdominal and thoracoabdominal aneurysms and to assess the certainty of the available evidence. Data SourcesMEDLINE, Embase and the Cochrane Library were searched from January 2000 to February 2026, supplemented by citation screening. Review MethodsPublished Kaplan Meier time-to-event data were digitised and reconstructed into individual patient datasets. Pooled survival probabilities were generated using validated methods for meta-analytic methods for survival curves. Certainty of evidence was assessed using the GRADE framework. ResultsTwenty-four studies comprising 8,886 patients were included. Pooled overall survival was 91.3% (95% CI: 90.7, 91.9) at 1 year, 73.0% (95%CI: 71.9, 74.0) at 3 years and 55.4% (95% CI: 53.9, 56.8) at 5 years. Estimated median overall survival was 6.36 years. At 5 years, freedom from aneurysm-related mortality was 96.4% (95%CI: 95.3, 97.2), freedom from reintervention was 66.5% (95%CI: 64.6, 68.2), and target vessel patency (TVP) was 94.8% (95%CI: 93.3, 96.0). Certainty of evidence was low for overall survival, aneurysm related mortality and reintervention, and very low for TVP. ConclusionElective F/BEVAR provides durable aneurysm exclusion with low aneurysm related mortality; however, long term survival declines substantially. There is a need for more robust survival data and improved tools to support patient selection, shared decision making, and assessment of anticipated benefit when considering prophylactic complex endovascular repair. What this paper addsThis study provides a time-to-event synthesis of medium and long term outcomes after elective F/BEVAR for complex abdominal and thoracoabdominal aortic aneurysms, analysing reconstructed survival data from 8,886 patients across 24 studies published between 2000 and 2025. This analysis provides empirical survival data to inform recent European Society for Vascular Surgery guidance, demonstrating a median survival of 6.36 years and showing that most late deaths are not aneurysm related. These findings quantify the divergence between procedural durability and long term survival, supporting an individualised treatment strategy grounded in assessment of life expectancy, competing risk and shared decision making.

Abstract Objective: To compare the safety and efficacy of bridging intravenous thrombolysis (IVT) plus endovascular thrombectomy (EVT) versus direct EVT in patients with acute ischemic stroke (AIS) due to anterior circulation large vessel occlusion (LVO) treated within the 6- to 24-hour time window. Methods: This is a retrospective analysis of prospective EVT registry from 10 comprehensive stroke centers in China and Singapore between 2019 and 2024. Eligible patients had anterior circulation LVO, underwent EVT within 6-24 hours of onset, had ASPECTS 6, NIHSS 6, and pre-stroke mRS 2. Patients were stratified into bridging IVT + EVT (IVT group) versus direct EVT alone (non-IVT group). Propensity score matching (1:2 ratio) was performed to balance baseline covariates. The primary outcome was 3-month favorable functional outcome (mRS 0-2). Secondary outcomes included successful recanalization (mTICI 2b-3), symptomatic intracranial hemorrhage (sICH), hemorrhagic transformation (HT) and 3-month mortality. In the matched cohort, binary outcomes were compared using the Cochran-Mantel-Haenszel test. Results: Of 772 included patients, 110 (14.2%) received bridging IVT and 662 (85.8%) received direct EVT. After propensity score matching, 202 non-IVT patients were matched to 101 IVT patients, with all covariates well-balanced (absolute SMD <0.10). In the matched cohort, bridging IVT was not associated with a significant difference in 3-month favorable outcome (44.55% vs. 47.03%; common OR 0.91; 95% CI 0.56-1.46), successful recanalization (91.09% vs. 90.10%; OR 1.11; 0.51-2.44), sICH (5.94% vs. 9.41%; OR 0.61; 0.24-1.58), HT (23.76% vs. 23.27%; OR 1.03; 0.57-1.85), or 3-month mortality (15.84% vs. 13.37%; OR 1.22; 0.62-2.37). Conclusion: In this large multicenter propensity score-matched analysis, bridging intravenous thrombolysis before endovascular thrombectomy in the 6- to 24-hour time window was not significantly associated with improved efficacy or increased safety risks compared with direct endovascular therapy alone.

BackgroundHemorrhagic transformation (HT) after endovascular thrombectomy (EVT) is a principal determinant of clinical outcome. Artificial intelligence (AI) algorithms for spontaneous hemorrhage detection exist, but none has been validated for post-procedural HT across multiple imaging modalities. MethodsWe conducted a multicenter diagnostic accuracy study within the Clinical Research Collaboration for Stroke in Korea registry (18 centers, 2022-2023). Patients who underwent EVT and received follow-up NCCT, GRE, or SWI within 168 hours were included. AI-derived hemorrhage volumes were compared against expert-determined ECASS classification. Three-month modified Rankin Scale (mRS) scores were evaluated for volume-outcome association. ResultsAmong 1,490 patients (median age 73; 57.4% male), HT was present in 41.4% and parenchymal hemorrhage (PH) in 11.1%. PH detection sensitivity exceeded 94% across all modalities (NCCT 95.4%, GRE 94.4%, SWI 98.3%), with AUCs of 0.900, 0.943, and 0.953, respectively. AI-derived volume correlated with 3-month mRS (Spearman {rho} = 0.353, P < 0.001); good outcome (mRS 0-2) declined from 61.8% to 6.7% across increasing volume categories. Among ECASS 0 cases, AI-positive patients had significantly worse outcomes than true-negatives (good outcome 48.2% vs 67.2%, mortality 10.7% vs 4.6%, P < 0.001). ConclusionsAI-based hemorrhage quantification provides high detection of clinically significant PH after EVT and demonstrates a dose-response association with functional outcome. AI-derived volume may serve as a continuous prognostic biomarker that identifies at-risk subgroups beyond categorical ECASS grading.

PurposeIntracranial atherosclerotic disease-related large vessel occlusion (ICAD-LVO) presents distinct challenges, particularly regarding the high risk of reocclusion and the need for specific management strategies. While several prediction scores exist to differentiate ICAD-LVO from embolic LVO (EMB-LVO), their external validity remains unproven. We aimed to externally validate six established prediction scores for differentiating the two. MethodsWe analyzed data from a prospectively maintained, two-center stroke registry (June 2021-March 2025). Consecutive patients who underwent mechanical thrombectomy and had complete clinical and imaging data necessary for calculating six scores (ISAT, REMIT, ABC2D, ATHE, ICAS-LVO, and Score-ICAD) were included. LVO etiology was defined based on angiographic findings during endovascular treatment. The discriminative performance of each score was assessed using the area under the receiver operating characteristic curve (AUC). ResultsOf 1,288 screened admissions, 91 patients met the inclusion criteria (ICAD-LVO, n = 18; embolic occlusion, n = 73). The AUCs (95% confidence interval) for differentiating etiology were: ISAT, 0.870 (0.664-1.000; P = 0.064); REMIT, 0.793 (0.676-0.911; P <0.001); Score-ICAD, 0.707 (0.582-0.833; P = 0.013); ABC2D, 0.627 (0.504-0.751; P = 0.095); ATHE, 0.600 (0.451-0.749; P = 0.230); and ICAS-LVO, 0.465 (0.301-0.630; P = 0.650). ConclusionIn this external validation, REMIT demonstrated the most robust and statistically significant discrimination between ICAD-LVO and EMB-LVO. Overall, scores incorporating imaging features outperformed those relying on clinical variables. These findings support the concept that ICAD-LVO represents a distinct pathophysiological entity from embolic occlusion and that accurate mechanism inference requires comprehensive imaging assessment of intracranial atherosclerotic disease beyond the occlusion site.

Background: Aneurysmal subarachnoid hemorrhage (aSAH) is a severe form of stroke associated with higher morbidity and mortality. Posterior circulation aneurysms are considered to have worse prognosis than anterior circulation aneurysms due to anatomical location, hemorrhage severity, and treatment complexity. We aimed to determine whether aneurysm location independently influences clinical outcomes following aSAH Methods: PubMed, Scopus, Embase, and Web of Science were searched from January 2000 to December 2025 for studies reporting outcomes in anterior or posterior circulation aSAH. The outcome analysis included mortality, functional recovery (modified Rankin Scale [mRS] 0-2 and 3-6 at 6 months and 1 year), hydrocephalus, delayed cerebral ischemia (DCI), and symptomatic cerebral vasospasm. Pooled proportions and subgroup comparisons were performed using random-effects meta-analysis (DerSimonian-Laird method). Publication bias was evaluated using contour-enhanced funnel plots and Egger's test. Results: Nineteen analytic entries from 18 studies (anterior: n = 1,625; posterior: n = 986; total N = 2,611) were included. Pooled mortality was 13% (95% CI: 10%-17%; I2 = 84.6%), with no significant difference between the anterior (14%; 95% CI: 10%-20%) and posterior (11%; 95% CI: 7%-18%) circulation subgroups (p = 0.437). Good functional outcome was 60% at 6 months (95% CI: 51%-67%) and 55% at 1 year (95% CI: 46%-64%), with no location-based differences. Hydrocephalus (35% vs 35%; p = 0.979) and DCI (17% vs 17%; p = 0.939) were comparable between subgroups. Symptomatic cerebral vasospasm was the only outcome differing significantly by location, occurring more frequently in anterior circulation aSAH (24% vs 11%; {chi}2 = 5.59; p = 0.018). Conclusion: Aneurysm location does not independently determine mortality, functional recovery, hydrocephalus, or DCI following aSAH. Symptomatic cerebral vasospasm was the only location-specific outcome. Admission neurological grade (World Federation of Neurosurgical Societies [WFNS]), rather than vascular territory, appears to be the primary determinant of mortality. Aneurysm location alone should not guide prognostic decisions or limit aggressive treatment.

BACKGROUNDSteno-occlusive diseases of the internal carotid artery (ICA) or middle cerebral artery (MCA) can lead to hemodynamic impairment, yet conventional imaging often fails to reflect metabolic dysfunction. Integrated positron emission tomography and magnetic resonance imaging (PET/MRI) allows simultaneous assessment of cerebral blood flow (CBF) and glucose metabolism. This study compared baseline perfusion and metabolic characteristics between patients receiving medical therapy or extracranial-intracranial (EC-IC) bypass surgery. METHODSThis retrospective study enrolled 34 patients with unilateral ICA/MCA stenosis or occlusion confirmed by digital subtraction angiography. All patients underwent 18F-FDG PET/MRI before treatment. Glucose metabolism was quantified using the cerebral metabolic rate of glucose (CMRGlu) from dynamic PET and the standard uptake value ratio (SUVR) from static PET. CBF was measured using three-dimensional arterial spin labeling with post-labeling delays of 2.0 and 2.5 seconds. Perfusion and metabolic parameters were compared across vascular territories. RESULTSBaseline clinical characteristics and long-term outcomes did not differ between groups (all P>0.05). Cerebral blood flow was similar across all arterial territories and post-labeling delays, with no hemispheric asymmetry detected (all P>0.05). In contrast, glucose metabolism was significantly lower in the surgical group, with reduced CMRGlu in the ischemic middle cerebral artery (23.58{+/-}7.46 vs 18.82{+/-}5.04mol/100g-1/min-1, P=0.037) and anterior cerebral artery territories (26.37{+/-}8.76 vs 20.71{+/-}5.78mol/100g-1/min-1, P=0.034). No differences were observed in the posterior cerebral artery or in SUVR across all regions (all P>0.05). CONCLUSIONSDespite similar perfusion profiles, the surgical group demonstrated lower glucose metabolism, suggesting that metabolic imaging may aid in identifying patients who could benefit from revascularization.

BackgroundEndovascular thrombectomy (EVT) has transformed the treatment of acute ischemic stroke (AIS). However, a substantial proportion of AIS patients experience poor outcomes despite successful recanalization, often due to severe neurological deterioration or life-threatening complications. Early identification of these high-risk patients remains a major unmet need. In this study, we developed and validated machine-learning (ML) models that integrate automated quantitative cerebrovascular morphology and collateral grading with demographic, clinical, laboratory, and imaging variables to predict major post-EVT complications and early neurological outcomes. MethodsUsing a prospectively collected database of 727 AIS patients that underwent EVT, we developed ML models to incorporate patient-specific vascular morphometry with conventional clinical, laboratory, and imaging data to predict emergence of early neurological deterioration (END), symptomatic intracranial hemorrhage (sICH), malignant brain edema (MBE) requiring surgical decompression, and neurogenic respiratory failure and dysphagia requiring tracheostomy/gastrostomy (TC/PEG). ResultsOur analysis of morphological features, including increased tortuosity and reduced vessel diameter, showed strong associations with complications. Morphology-informed (MI) models consistently outperformed baseline-clinical (BC) models for patients with END (AUROC 0.81 for MI model vs. 0.73 for BC), sICH (AUROC 0.68 MI vs. 0.56 BC model), MBE (AUROC 0.67 MI model vs. 0.56 BC), or patients who underwent TC/PEG (AUROC 0.66MI vs. 0.58 BC model). Statistical testing confirmed significant AUROC improvements for END, sICH and mRS (p < 0.05), Finally, patient-specific calibrated probability profiles enabled individualized, multidimensional risk stratification, revealing distinct complication-specific risk patterns across patients. ConclusionsThese findings demonstrate that cerebrovascular structure--an often overlooked yet physiologically fundamental determinant of ischemic injury and reperfusion dynamics--provides significant predictive information that is not captured by standard clinical or visual imaging assessments. Automated vascular segmentation and collateral grading techniques enable rapid and objective integration of cerebrovascular metrics into prognostic models, offering a scalable tool for precision risk stratification, supporting earlier intervention, targeted monitoring, and improved post-EVT management.

Background. Carotid webs (CaWs) are shelf-like protrusions in carotid bifurcation recognized as a potential cause of ischemic stroke. However, their impact on wall-based hemodynamic metrics (TAWSS, OSI, RRT) in distinguishing from normal bifurcations remains unclear. Methods. Carotid geometries were reconstructed from CT angiography in patients with CaWs, classified as symptomatic (with ischemic stroke) or asymptomatic (incidentally detected), and controls with normal bifurcations. Influence of three blood viscosity models (Newtonian, Carreau-Yasuda, Casson) was evaluated. Metrics were quantified using a Gaussian-weighted spatial averaging method and compared between groups. Results. CFD simulations were performed in 22 CaW cases (16 symptomatic, 6 asymptomatic) and 6 normal bifurcations. Simulations predicted recirculation corresponding to delayed contrast clearance on DSA. Viscosity models had minimal influence on flow patterns (<2% differences). CaWs showed greater inter-patient variability than normal bifurcations, but overlap remained (e.g., TAWSS 3.39 (2.72-8.96) vs 4.18 (3.09-4.56) Pa, p = 0.858). Symptomatic CaWs showed lower TAWSS and higher OSI and RRT than asymptomatic CaWs (TAWSS 3.39 vs 6.63 Pa), although did not reach statistical significance (p > 0.25). Conclusion. Symptomatic CaWs show lower shear stress and stronger oscillations than asymptomatic CaWs. However, wall-based hemodynamic metrics alone may not distinguish CaWs from normal carotid geometries.

Background: The past decade has witnessed rapid growth of clinical-trial programs in Europe and Asia, with randomized clinical trials (RCTs) publications from these regions outpacing those of the U.S. However, limited data exist quantifying their relative influence on practice-defining results. Here, we evaluate these shifts by analyzing geographic origin, funding source, and clinical impact of practice-changing RCTs. Methods: From the 2018 and 2026 American Heart Association/American Stroke Association (AHA/ASA) Acute Ischemic Stroke (AIS) Guidelines, we identified RCTs supporting new recommendations and extracted geographic origin (China/Europe/USA/Other), funding source (government/academic/non-profit vs. industry (private/mixed); NIH vs. non-NIH), and research topic (endovascular therapy (EVT), thrombolysis, imaging, poststroke care, and prehospital and systems of care). Analyses used unweighted, reference-density-weighted, and clinical-impact-weighted strategies. Temporal trends were assessed using the chi-square/Fisher?s exact tests, with Rao-Scott adjusted chi-square tests accounting for weighting. Results: We identified 21 new recommendations (47 RCTs) in 2018 and 45 (89 RCTs) in 2026. In 2018, Europe led (51.1%), followed by the U.S. (31.9%), while China and other regions contributed minimally. By 2026, Europe remained first (36%), China rose to second (29.2%), and the U.S. declined to the smallest share (14.6%), across all weighted analyses (p<0.01). NIH-funded trials declined significantly from 21.3% (unweighted), 27.4% (reference-density-weighted), and 27.3% (clinical-impact-weighted) in 2018 to 4.5%, 4.8%, and 3.4%, respectively in 2026 (p<0.01 across all weighted strategies). Conclusion: In this analysis, we identify a shift away from U.S.-based clinical trials and increasing contributions from China. U.S.-based RCTs fell from the second most cited to the least cited sources of practice-changing recommendations. NIH-funded research fell from nearly one-quarter in 2018 to <5% in 2026, highlighting increasing dependence on non-U.S. studies for U.S.-based care. These findings raise questions about the effectiveness of current AIS research paradigms in the U.S. Keywords: Acute Ischemic Stroke, Endovascular Thrombectomy, Thrombolytic Therapy, NIH Funding

Objective: Neuroendoscopy has emerged as a crucial minimally invasive strategy for the treatment of intracranial hemorrhage (ICH). This bibliometric analysis aims to systematically delineate the global research architecture and evolution of neuroendoscopic ICH research over the past two decades. Methods: Relevant publications were retrieved from the Web of Science Core Collection using a reproducible search strategy. Bibliometric tools were applied to analyze contributions from countries, institutions, authors, publications, keywords and journals, enabling the construction of a comprehensive knowledge map and evolutionary framework of this field. Results: A total of 403 articles were identified, involving 2128 authors from 555 institutions across 43 countries. The publication trajectory exhibited fluctuating growth, reflecting the dynamic interplay between clinical demand and technological maturation. China contributed the highest publications and citation impact, followed by the US, jointly anchoring the global influence of the field. The research keywords have evolved from ?intracerebral hemorrhage? and ?initial conservative treatment? to ?augmented reality.? Thematic evolution analysis revealed a clear progression from early emphasis on operative feasibility, safety, and perioperative outcomes toward more rigorous evidence appraisal and the refinement of context-specific clinical indications, accompanied by continuous technological innovation. Conclusion: These findings collectively position neuroendoscopy as a cornerstone of modern ICH management, reshaping clinical strategies toward precision, minimal invasiveness, and multimodal intervention. Future progress will depend on strengthened international collaboration to generate high-quality evidence that supports patient stratification. The integration of emerging technologies, including advanced endoscopic robotics, is expected to further accelerate the translational and clinical landscape of neuroendoscopic ICH therapy.

BackgroundIn aortic arch surgery, bilateral selective antegrade cerebral perfusion (bSACP) maintains cerebral blood flow during circulatory arrest. bSACP is often delivered using a single pump with a Y-connector, dividing the flow. Current practice has veered towards perfusion of the left common carotid artery by cannula and the right subclavian artery or axillary artery by a vascular graft. Under this configuration, inflow distribution may be sensitive to left-sided cannula resistance, particularly in patients with limited collateral circulation, potentially reducing left-hemispheric pressure and flow despite bSACP. We investigated how cannula design influences perfusion pressure and arterial inflow distribution during bSACP. MethodsFour perfusion cannulas with different flow resistances were characterized using bench measurements (40-200 ml/min) and computational fluid dynamics (CFD). The CFD cannula models were then integrated into patient-specific CFD models of the cerebral circulation from three patients with varying collateral circulation/capacity. Both flow- and pressure-controlled pump strategies were simulated. ResultsBench measurements showed substantial variation in flow resistance between the cannulas, which was accurately reproduced by CFD. For the patient-specific analysis, cannula choice affected perfusion through roughly doubled pressure laterality and halved left-side inflow between the most extreme cannulas. Still, perfusion pressure was kept within recommended levels in two subjects but was low in one. Left-side arterial inflow varied between 70-150 ml/min. ConclusionsWe isolated the effects of cannula design on cerebral pressure and blood inflow distribution during bSACP, highlighting potential pitfalls in patients with limited collateral circulation.

Background: Stroke guidelines recommend intravenous thrombolysis (IVT) within 4.5 hours of symptom onset for patients with minor acute ischemic stroke (AIS) but disabling symptoms. However, such patients are often overlooked for treatment, increasing their risk of stroke-related disability. Tenecteplase is endorsed as an alternative to alteplase for IVT in patients with AIS. More evidence is required regarding its efficacy and safety in the minor stroke population. Methods: This post hoc analysis of the ORIGINAL randomized clinical trial aimed to evaluate the efficacy and safety of tenecteplase versus alteplase in the patient subgroup with minor (National Institutes of Health Stroke Scale [NIHSS] 5) disabling stroke. Primary outcome was the proportion of patients with a modified Rankin Scale (mRS) score of 0 or 1 at Day 90. Results: Data were analyzed for 299 patients treated with tenecteplase 0.25 mg/kg and 297 patients treated with alteplase 0.9 mg/kg. At Day 90, 86.3% of tenecteplase recipients and 82.8% of alteplase recipients achieved a mRS score of 0 or 1 (risk ratio=1.04 [95% confidence interval 0.971?1.114]; non-significant). No heterogeneity of treatment effect was observed across predefined subgroups according to baseline NIHSS score, time to drug administration, sex, age, presence (yes/no) of atrial fibrillation and diabetes and thrombectomy performed. No statistically significant differences were observed between tenecteplase and alteplase across secondary efficacy and safety outcomes. Conclusions: The comparable efficacy and safety of tenecteplase 0.25 mg/kg and alteplase 0.9 mg/kg in the minor stroke population of the ORIGINAL randomized clinical trial suggests that tenecteplase is a suitable alternative to alteplase in this setting. Trial registration: ClinicalTrials.gov NCT04915729 (ORIGINAL randomized clinical trial; https://clinicaltrials.gov/study/NCT04915729). Submitted 4 June 2021. Key words: acute ischemic stroke, alteplase, intravenous thrombolysis, minor stroke, tenecteplase

Background and PurposeEmbolic stroke of undetermined source (ESUS) emains a major diagnostic challenge in vascular neurology, as a substantial proportion of patients lack an identifiable embolic source despite standardized diagnostic workup. The failure of empiric anticoagulation strategies highlights the need for individualized, mechanism-oriented risk stratification. We aimed to develop a machine learning-based framework to estimate the most likely embolic source in ESUS using routinely available clinical data. MethodsWe retrospectively analyzed consecutive ESUS patients admitted to the Stroke Unit of Vall dHebron Hospital between 2020 and 2024. Three supervised machine learning models (XGBoost, Random Forest, and regularized logistic regression) were trained to independently predict the presence of left atrial enlargement (LAE), left ventricular dysfunction or akinesia (LVD), and complex aortic plaques (AP), based on demographic, clinical, laboratory, and imaging variables available at diagnosis. Model interpretability was assessed using permutation importance and SHAP analyses. ResultsAmong 1,741 ESUS patients (mean age 71.5{+/-}14.6 years; 48.3% women), LAE was present in 40.5%, AP in 11.0%, and LVD in 6.5%. XGBoost achieved the best overall performance across targets (PR-AUC: 0.71 for LAE, 0.29 for AP, 0.44 for LVD). Distinct and biologically coherent risk profiles emerged. LAE was driven by older age, elevated NT-proBNP, higher stroke severity, and a non-linear association with cholesterol. AP was associated with advanced age and traditional vascular risk factors. LVD showed a cardiomyopathic pattern characterized by elevated NT-proBNP, younger age, male sex, and severe strokes. ConclusionsA machine learning-based approach can provide probabilistic, mechanism-oriented stratification in ESUS, capturing non-linear interactions among routinely available variables. This framework may support clinicians in prioritizing targeted diagnostic pathways and tailoring secondary prevention strategies, pending external validation.

PurposeEndovascular therapy is preferred over open surgery due to its minimally invasive nature, faster recovery, and lower perioperative risk; however, fluoroscopy guided procedures are limited by radiation exposure, high equipment costs, and reliance on highly skilled operators. This study aims to develop and evaluate a lightweight, portable robotic system for autonomous guidewire navigation to improve safety, accessibility, and operator independence. MethodsA compact 400 g robotic device was designed with millimeter scale positioning accuracy, servo current based real-time haptic feedback, precise axial rotation, automated retraction advance control, and compatibility with standard endovascular tools. Miniature linear actuated servomotors replicate skilled manual maneuvers using impedance control. Upon tip contact, the system advances the guidewire by 1 mm, measures current changes, classifies lesion stiffness (soft, medium, stiff), and adapts virtual mass-spring-damper gains to regulate push speed and applied force. Bench experiments were conducted using flexible tubing with inserts simulating 20-80% stenosis and two current thresholds (75 mA and 94 mA). ResultsRetraction frequency increased with stenosis severity, validating the autonomous control strategy. Lesion stiffness classification achieved F-scores of 0.83, 0.77, and 0.95 for soft, medium, and stiff conditions, respectively, demonstrating reliable discrimination and adaptive force modulation. ConclusionsThe proposed system enables autonomous and adaptive guidewire advancement with high classification accuracy using low-cost, current based sensing and impedance control. Its lightweight and portable design reduces dependence on continuous manual operation and specialized imaging infrastructure, supporting safer and faster interventions and potential deployment in prehospital or resource-limited settings. This prototype advances the development of more accessible and operator-independent endovascular therapy.

BackgroundAneurysmal subarachnoid haemorrhage (aSAH) carries a case fatality rate exceeding 35-40%, with early rebleeding occurring predominantly within the first 2-6 hours of ictus, representing the single most preventable determinant of catastrophic outcome. Tranexamic acid (TXA), a competitive plasminogen inhibitor that stabilises the perianeurysmal haemostatic clot, has been evaluated as a pre-occlusion bridge therapy for over four decades. Prior meta-analyses have been methodologically constrained by heterogeneous treatment-duration pooling, inclusion of non-randomised evidence, and the absence of prospective inferential boundary testing. The present analysis restricts inclusion exclusively to randomised controlled trials (RCTs), applies a pre-specified duration-response stratification (ultra-early/short-course [UE/SC] [&le;]72 hours versus prolonged course), and deploys Trial Sequential Analysis (TSA) to determine whether cumulative randomised evidence has crossed definitive efficacy or harm thresholds. MethodsPRISMA 2020-compliant systematic review and meta-analysis restricted to RCTs, prospectively registered in PROSPERO (CRD42026133240). Electronic databases (MEDLINE, EMBASE, Cochrane CENTRAL, Web of Science) were searched from inception to December 2024. Eligible trials randomised adults with CT-confirmed aSAH to TXA versus placebo or standard care. Primary efficacy outcome: rebleeding incidence. Primary safety outcomes: delayed cerebral ischaemia (DCI), all-cause mortality, and poor functional outcome at 3-6 months. Effect sizes were pooled as risk ratios (RR) or odds ratios (OR) with 95% confidence intervals (CI) using random-effects meta-analysis (DerSimonian-Laird). Heterogeneity was assessed by I2 and Cochrans Q. Risk of bias was appraised via Cochrane RoB 2.0. GRADE certainty ratings were assigned. TSA was performed with two-sided alpha=0.05, power=80%, and an MCID of 30% relative risk reduction for rebleeding. ResultsSeven RCTs enrolling 2,194 patients in total were included. TXA significantly reduced rebleeding across all pooled RCTs (RR 0.58, 95% CI 0.44-0.76; I2=41%; GRADE: moderate certainty), with TSA confirming that the cumulative Z-curve crossed the adjusted monitoring boundary, establishing definitive evidence of efficacy. The duration-response contrast for DCI was unambiguous: ultra-early/short-course TXA ([&le;]72 hours) conferred no excess DCI risk (RR 0.97, 95% CI 0.78-1.19), whereas prolonged-course TXA significantly elevated DCI risk (RR 1.42, 95% CI 1.12-1.81; TSA harm boundary crossed). Despite rebleeding reduction, neither UE/SC nor prolonged TXA improved all-cause mortality (RR 0.98, 95% CI 0.84-1.14) or good functional outcome (OR 0.86, 95% CI 0.66-1.12 in the UE/SC stratum). TSA confirmed insufficient cumulative evidence for functional benefit across all subgroups. ConclusionsTreatment duration is the critical and sole modulator of TXAs risk-benefit ratio in aSAH. Ultra-early, short-course TXA eliminates the DCI penalty while preserving a robust rebleeding-reduction signal. However, no adequately powered RCT demonstrates improvement in functional outcome or survival with any TXA regimen. These findings definitively argue against prolonged TXA and support its selective, time-limited use as a haemostatic bridge during unavoidable pre-occlusion delays, pending subgroup-stratified trials powered for functional endpoints.

Objective: To assess ethnic disparities in time to hospital presentation, use of acute reperfusion therapies, and in-hospital treatment times among patients presenting with stroke in a Dutch emergency department. Methods: In this single-centre observational cohort study, we included patients with a first-ever ischemic stroke between September 2020 and September 2021. Patients were categorized by ethnicity (with or without migration background). Demographic and stroke characteristics were compared between groups. Outcomes included: rates of presentation outside therapeutic time window, acute reperfusion therapy (intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT)), and, when applicable, door-to-treatment time (DTTT), with a door-to-needle time (DTNT) and door-to-groin time (DTGT) for IVT and EVT respectively. Univariable and multivariable linear and logistic regression analyses were performed, adjusted for age, sex, and NIHSS at presentation, where appropriate. Results: A total of 232 patients were included, of whom 62 (26.7%) had a migration background. These patients were younger (66.6 vs 71.2 years) and more frequently had diabetes (27.4% vs 15.9%). Sex distribution was similar (59.7% vs 60.6% male). Stroke etiology differed between groups with less cardio-embolism (4.8% vs 15.3%) and more small vessel disease (69.4% vs 48.2%) among patients with a migration background. These latter patients presented more often outside the therapeutic time window (53.2% vs 37.1%; OR 1.90; 95% CI 1.05-3.45). EVT was less frequently performed in patients with a migration background compared to those without (8.1% vs 22.4%; OR 0.28; 95% CI 0.10-0.75). There were no significant differences in treatment times (DTTT 38min vs 30min, DTNT 35min vs 26min, DTGT 64min vs 54min). Conclusion: Patients with a migration background were more likely to present outside the therapeutic time window and had a lower rate of EVT. In order to improve access for these patients, more insight into prehospital and within hospital barriers and facilitators for appropriate management are needed.

Background Venous thromboembolism (VTE) remains a major cause of perioperative morbidity in cranial neurosurgery, yet clinical practice varies widely, and formal guidelines are inconsistent. Understanding internationally sampled neurosurgical practice is essential for informing consensus and future trials. Methods An international, 2-stage cross-sectional, internet-based survey was conducted. Practising neurosurgeons performing elective adult cranial surgery were eligible. Descriptive statistics were used to summarise practice. Responses covered patterns of pre-operative haemostasis decision making, use and timing of mechanical and/or chemical prophylaxis, use of perioperative imaging prior to anticoagulation, and frequency of clinical assessment for VTE. Associations with geographical income status, subspecialty, and years post-certification were statistically tested. Practice heterogeneity was quantified and contextual influence was summarised using mean effect sizes across stratifying variables in order to determine domains of true equipoise. Results Of 585 responses, 456 (78%) met criteria for inclusion: representing 322 units across 78 countries (71% high-income). Thirteen per cent reported no departmental VTE plan; 23% followed no guidelines and 12% used multiple. Routine pre-operative testing almost universally included haemoglobin/platelets/haematocrit, with fibrinogen more common in high-income settings. Compared with high-income country respondents, low- and middle-income respondents reported higher haemoglobin transfusion thresholds (>90 g/dL; p<0.001) and shorter antiplatelet interruption (p[&le;]0.03), and less frequent outpatient VTE assessment (p<0.001). Mechanical prophylaxis was common (TEDs 81%, IPC 62%), typically started pre- or intra-operatively. Among those completing the chemoprophylaxis section (n=310), 57% required a CT or MRI scan before LMWH which was then initiated on average 31.4 hours after surgery. 1% of respondents did not routinely use LMWH. Many clinical decisions demonstrated statistical equipoise ie. high heterogeneity with low contextual influence. Conclusion Peri-operative haemostasis and VTE prophylaxis practices in adult elective cranial neurosurgery vary substantially worldwide, with some decisions reflecting geographical or socioeconomic differences and many others reflecting true clinical equipoise rather than contextual determinants. By mapping contemporary real-world practice across diverse health-system contexts, this study provides a necessary empirical foundation for rational trial design and future guideline development.

BackgroundSuccessful recanalisation without functional independence is a frequent phenomenon following endovascular thrombectomy for large vessel occlusion stroke. AimTo demonstrate safety and efficacy of adjunct tirofiban therapy after endovascular thrombectomy in patients with anterior circulation large vessel occlusion stroke achieving successful recanalization defined as modified Thrombolysis In Cerebral Infarction (mTICI) 2b-3. DesignThe study of adjunct tirofiban treatment after successful endovascular thrombectomy recanalisation (ATTRACTION) is a multicenter, prospective, double-blind, randomized trial enrolling 1360 patients in China. Eligible patients will be randomised 1:1 to either the tirofiban or placebo group. OutcomeThe primary efficacy outcomes is assessed as the proportion of participants with a modified Rankin Scale (mRS) score of 0-2 at 90 days, and the primary safety outcome is symptomatic intracranial haemorrhage within 48 hours from randomisation. ConclusionThis study will provide evidence on the efficacy and safety of sequential tirofiban therapy after successful recanalisation in patients with anterior circulation large vessel occlusion stroke. Trial registration numberNCT06265051 WHAT IS ALREADY KNOWN ON THIS TOPICSuccessful recanalization without functional independence is a frequent phenomenon following endovascular thrombectomy and previous small-sample, retrospective studies supported the administration of adjunct tirofiban therapy in patients after endovascular thrombectomy achieving successful recanalization. WHAT THIS STUDY ADDSThe ATTRACTION trial aims to access the efficacy and safety of adjunct tirofiban therapy and the protocol describes the rationale and design of the trial. HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICYATTRACTION trial will inform whether tirofiban therapy after successful recanalisation by endovascular thrombectomy can improve patient outcomes.