Stroke: Vascular and Interventional Neurology

Background Endovascular treatment of unruptured intracranial aneurysms (UIAs) often requires dual antiplatelet therapy with aspirin and a P2Y12 inhibitor. Clopidogrel remains widely used, but variable bioactivation and high on-treatment platelet reactivity have prompted interest in alternatives such as prasugrel. We compared thromboembolic and hemorrhagic outcomes after clopidogrel versus prasugrel use in endovascular UIA treatment. Methods We queried the TriNetX Global Collaborative Network for adults with UIA who underwent endovascular treatment between 2016 and 2025 and received aspirin plus clopidogrel or prasugrel. Cohorts were matched 1:1 using propensity score matching based on demographics and comorbidities. Outcomes were assessed at 6 months and 1 year and reported as odds ratios (ORs) with 95% confidence intervals (CIs). Results Among 15,496 adults, 711 matched pairs were included. At 6 months, no significant differences were observed for in-stent thrombosis (OR 0.77, 95% CI 0.38?1.57; p=0.47), cerebral infarction (OR 1.04, 95% CI 0.75?1.46; p=0.80), cerebral hemorrhage (OR 1.07, 95% CI 0.80?1.44; p=0.65), or gastrointestinal hemorrhage (OR 0.84, 95% CI 0.43?1.64; p=0.61). Findings remained nonsignificant at 1 year. Conclusions In this propensity-matched TriNetX analysis, clopidogrel and prasugrel were not associated with significant differences in thromboembolic or hemorrhagic outcomes after endovascular UIA treatment. Prasugrel may be a reasonable alternative P2Y12 inhibitor in selected patients, including those with suspected or documented clopidogrel non-response.

Purpose: The aims of this study were to develop an externally validated deep learning vascular segmentation model for digital enhancement of vertebral artery dissection detection on CTA and to assess clinical utility of the model through a paired crossover reader study. Materials and Methods: This retrospective, IRB-approved study conducted from September 2024 to July 2026 included an internal training cohort of 84 manually segmented CTAs plus 17 CTAs from the RSNA Intracranial Aneurysm Challenge (101 CTAs total) and an external testing cohort of 40 CTAs (22 positive, 18 negative for vertebral artery dissection). A nnU-Net (version 2) model was trained using five-fold cross-validation with the entire training cohort. Technical performance was evaluated using the Dice similarity coefficient (DSC). A two-part crossover reader study included 10 readers who assessed diagnostic accuracy, confidence, and interpretation time with and without segmentation-based augmentation. Statistical analyses included McNemar's exact test (accuracy) and Wilcoxon signed-rank test (confidence, time), with P < .05 considered significant. Results: The model achieved a DSC of 0.96 (SD 0.01). In the reader study, diagnostic accuracy was lower with augmentation than without (0.72 vs 0.84, P < 0.001), while confidence (3.98 vs 3.96, P = .77) and interpretation time (137.3 vs 166.7 seconds, P = .54) did not differ significantly. Subjectively, 7 of 10 readers reported they would use the tool routinely in acute or trauma settings. Conclusion: Although the deep learning model demonstrated accurate segmentation of vascular structures, further validation is needed to establish its utility for enabling accurate diagnosis of VAD in fast-paced clinical settings.

BACKGROUND: Subarachnoid hemorrhage (SAH) induces inflammatory responses and subsequent immune cell activation, which may contribute in cerebral vasospasm, microcirculatory impairment and poor neurological outcomes. Although cerebral vasospasm has traditionally been considered a major cause of delayed cerebral ischemia after SAH, therapies targeting angiographic vasospasm have not consistently improved functional outcomes. Early inflammatory responses may contribute to microcirculatory impairment, cerebral vasospasm, and subsequent neurological injury. Herein, we investigated whether interleukin-10 (IL-10), an anti-inflammatory cytokine, improves these outcomes in an experimental SAH model. METHODS: Mice received intramuscular injections of either an adeno-associated virus encoding IL-10 (AAV/IL-10) vector or an AAV expressing green fluorescent protein (AAV/GFP) vector (control). India ink angiography was performed to assess the diameter of the sphenoidal segment of the middle cerebral artery (MCA), the total length of the visible cortical arteries, and cortical staining intensity, as indices of cerebral vasospasm, microcirculatory impairment, and cerebral perfusion, respectively. Perivascular inflammatory cell infiltration and cytokine levels were assessed using immunohistochemistry and ELISA. We also evaluated the therapeutic efficacy of the AAV/IL-10 vector when administered immediately after SAH induction. RESULTS: IL-10 overexpression significantly improved neurological outcomes after SAH and was associated with attenuated cerebral vasospasm and microcirculatory impairment, as well as preservation of cerebral perfusion. It also significantly reduced neutrophil and macrophage infiltration around the internal carotid artery and attenuated SAH-induced elevations in IL-6 and matrix metalloproteinase-3 levels. Mice treated with the AAV/IL-10 vector immediately after SAH induction showed significant improvements in neurological scores and cerebral perfusion. CONCLUSIONS: AAV-mediated IL-10 overexpression improves neurological outcomes after SAH, likely by attenuating inflammatory responses, cerebral vasospasm, and microcirculatory impairment. These findings suggest that IL-10-based anti-inflammatory therapy is a promising therapeutic strategy for SAH.

Background: Dexmedetomidine (DEX) and midazolam (MDZ) are commonly used agents for conscious sedation in patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT). While DEX offers superior sedation quality and potential neuroprotective effects, it is also associated with risk of hemodynamic instability. High-quality evidence directly comparing their impact on functional outcomes after EVT is lacking. This trial aims to determine whether conscious sedation with DEX, compared to MDZ, improves functional outcomes in patients with AIS due to anterior circulation large vessel occlusion (LVO) undergoing EVT. Methods: PEACE (Dexmedetomidine versus Midazolam for Conscious Sedation during Endovascular Stroke Thrombectomy) is a prospective, randomized, open label, blinded-endpoint, multicenter trial. Up to 810 patients with AIS due to LVO in the anterior circulation within 24 hours of last known well will be randomly assigned in a 1:1 ratio to receive either DEX or MDZ for conscious sedation during EVT across 30 centers in China. Results: The primary end point is the proportion of patients achieving a modified Rankin Scale (mRS) score 0-2 at 90 days, analyzed in the intention-to-treat population using a modified Poisson regression model, with results expressed as a risk ratio. Key secondary outcomes include the ordinal distribution of mRS scores at 90 days, and successful recanalization. Safety outcomes include symptomatic intracranial hemorrhage within 48 hours, and mortality at 90 days. Conclusion: The PEACE trial will provide definitive, high-level evidence on the comparative efficacy and safety of DEX versus MDZ for conscious sedation during EVT in patients with AIS due to LVO in the anterior circulation, with the goal of guiding clinical practice.

Background Endovascular thrombectomy (EVT) is used selectively for vertebrobasilar artery occlusion (VBAO), but its net value in mild deficits remains uncertain. We performed a hierarchical win-ratio analysis of EVT versus best medical management (BMM) in patients with acute VBAO and admission National Institutes of Health Stroke Scale (NIHSS) scores of 10 or less. Methods We performed a secondary analysis of a multicenter retrospective registry of acute VBAO with admission NIHSS scores of 10 or less. EVT plus BMM was compared with BMM alone in the overall cohort and in admission NIHSS strata of 0-5 and 6-10. The primary hierarchy ranked death status through common follow-up, 90-day modified Rankin Scale score, and symptomatic intracranial hemorrhage (sICH). All EVT-BMM pairs were compared sequentially and classified as an EVT win, BMM win, or tie. The adjusted analysis used stabilized inverse probability of treatment weighting (IPTW), with weights truncated at the 1st and 99th percentiles in a sensitivity analysis. Results The analysis included 1,232 patients: 428 underwent EVT and 804 received BMM. In the unweighted overall analysis, EVT had 146,674 wins, BMM had 149,958 wins, and 47,480 ties, yielding a WR of 0.98 (95% CI, 0.84-1.15; P = 0.749). After stabilized IPTW, the WR was 0.96 (95% CI, 0.80-1.14; P = 0.618). Sensitivity analyses did not show a robust overall association favoring EVT. In exploratory NIHSS-stratified analyses, the WR was 0.80 (95% CI, 0.61-1.05; P = 0.101) for NIHSS scores of 0-5 and 1.36 (95% CI, 1.10-1.68; P = 0.004) for scores of 6-10. Conclusions EVT was not associated with an overall net advantage over BMM in this hierarchical analysis. The exploratory signal among patients with admission NIHSS scores of 6-10 suggests that EVT may be feasible in selected patients and warrants confirmation in randomized trials; for patients with NIHSS scores of 0-5, EVT use should remain cautious and individualized.

Background: Evidence regarding delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) remains sparse. We aimed to identify its predictors and occurrence and evaluate its role in ischemic stroke and functional outcome under treatment with interventional rescue therapy (IRT). Methods: This retrospective single-center study included 628 adults with aSAH from 2014?2023. The primary endpoint was occurrence of refractory DCI (= refractory despite induced hypertension) treated with at least one IRT. Multivariable models evaluated refractory DCI, new ischemic stroke, and poor functional outcome (mRS 3?6) at 6?12 months. Results: Among 628 included patients, 61 who died within 3 days were excluded from DCI analysis; 166/567 (29%) developed refractory DCI. Younger age (OR = 0.98; P<0.001), female sex (OR = 0.57; P=0.007), and higher WFNS grade (OR = 1.18; P=0.011) were independently associated with refractory DCI. Earlier first IRT was associated with longer DCI duration (IRR = 0.88; P<0.001) and more required IRTs (IRR = 0.91; P<0.001). IRT was performed later than day 14 in 29/166 patients (17.5%); none was older than 70 years. Refractory DCI was associated with new ischemic stroke (OR = 4.68; P<0.001) and poor functional outcome (OR = 2.37; P<0.001); earlier first IRT was associated with poor outcome within the refractory DCI subgroup (OR = 0.86; P=0.03). Outcomes after 1?2 IRTs did not differ from those without refractory DCI (P=0.4), whereas ?3 IRTs were associated with poor outcome (P=0.04). Conclusions: Refractory DCI affected 29% of aSAH patients, predominantly younger women and patients with poorer initial neurological status, and extended beyond day 14 in nearly 20% of affected patients, none of whom was older than 70 years. Refractory DCI and earlier onset were associated with poorer radiological and functional outcomes. The absence of a detected outcome difference after 1?2 IRTs suggests that favorable outcomes may remain achievable despite refractory DCI.

Endovascular thrombectomy (EVT) improves outcomes in acute ischemic stroke caused by large vessel occlusion. Despite successful recanalization, early neurological deterioration (END) remains frequent and predicts poor outcomes. Disturbances in cerebral autoregulation may contribute to END, yet reliable bedside predictors are limited. Transcranial Doppler (TCD) provides noninvasive bedside assessment of cerebral blood flow velocities and may identify hemodynamic patterns associated with post-EVT deterioration. PRECISE-TCD is a prospective, single-center observational study enrolling 180-300 patients undergoing EVT for anterior circulation large vessel occlusion at a tertiary academic medical center. TCD examinations will be performed as soon as feasible after EVT, daily through 72 hours, and near END events. Hemodynamic parameters including peak systolic velocity (PSV), end-diastolic velocity (EDV), mean flow velocity (MFV), and pulsatility index (PI) will be measured in bilateral MCA, ACA, PCA, carotid siphon, vertebrobasilar, and ophthalmic artery territories. The primary outcome is the association between TCD-derived parameters and END within 72 hours, defined as an increase of [&ge;]4 points in total NIHSS score, an increase of [&ge;]1 point in NIHSS subcategory 1a, radiologic evidence of intracranial hemorrhage within 72 hours, or any neurological change prompting emergent head CT at clinician discretion. Secondary outcomes include NIHSS at 24 hours and discharge, discharge disposition, and modified Rankin Scale (mRS) at 90 {+/-} 10 days after hospital discharge. Joint models for longitudinal and time-to-event data will determine the association between TCD parameter trajectories and time to END. Unsupervised clustering will identify TCD-based hemodynamic phenotypes using vessel velocities, pulsatility indices, hemispheric asymmetry measures, collateral flow, and temporal trajectory patterns. We hypothesize that abnormal post-EVT hemodynamic phenotypes will correlate with END and hemorrhagic transformation. Identifying such signatures may support development of TCD-guided, individualized blood pressure strategies to reduce secondary injury after reperfusion and inform future interventional trials. The study is registered at ClinicalTrials.gov (NCT07013396).

Introduction Mechanical thrombectomy has been well-established as the standard of care treatment for patients with moderate to severe acute ischaemic stroke secondary to large vessel occlusion. However, the clinical value of endovascular treatment (EVT) in patients presenting with minor stroke and low baseline National Institutes of Health Stroke Scale scores remains incompletely defined, with limited high-quality clinical evidence. This protocol outlines the methodology of a randomized trial designed to evaluate whether EVT combined with best medical therapy (BMT) achieves superior functional outcomes relative to BMT alone among patients with minor stroke. Methods and analysis Eligible patients with acute minor anterior circulation ischaemic stroke and confirmed large vessel occlusion (n=264) will be randomized via a computer generated block randomization sequence to receive either EVT plus BMT (intervention arm) or BMT alone (control arm). The primary efficacy outcome is the proportion of participants achieving excellent functional recovery, defined as a modified Rankin Scale score of 0 or 1 at 90 days. Primary safety outcomes comprise symptomatic intracranial haemorrhage within 48 hours after randomization (classified according to Heidelberg criteria) and all cause mortality at 90 days. Participants will be considered eligible if they satisfy all of the following inclusion criteria: (1) enrolment within 24 hours of stroke symptom onset or time last known well; (2) baseline NIHSS score of 2 - 5 accompanied by at least one focal neurological deficit (including altered consciousness, facial palsy, limb weakness, aphasia or hemispatial neglect); (3) angiographically confirmed acute occlusion of the intracranial internal carotid artery, the M1 segment of the middle cerebral artery, or a dominant M2 branch; (4) a hypoperfusion volume (Tmax >6s) [&ge;] 50mL on computed tomography or magnetic resonance perfusion imaging. Both intention to treat and per protocol analyses will be undertaken, and potential sources of heterogeneity in treatment effect magnitude will be explored. Ethics and Dissemination This study was approved by the ethnic committee from the First Affiliated Hospital of Wannan Medical University (2023-IRB90). The findings of this study will be disseminated through publication in peer-reviewed journals. Registration URL:https://www.clinicaltrial.gov; Unique identifier: NCT06143488.

Background Passive advancement--antegrade movement of the aspiration catheter upon inner delivery device withdrawal without active operator force--is a physical phenomenon observed during mechanical thrombectomy, with anecdotal reports of favorable recanalization outcomes. This study characterizes its prevalence and associations with recanalization. Methods Consecutive thrombectomy cases at two high-volume stroke centers (January 2019-December 2025) were retrospectively reviewed. Stored fluoroscopy and angiograms were assessed for passive advancement and final catheter tip position at arterial branch points. Per-pass and per-vessel mixed-effects multivariable regression identified independent associations with eTICI score, first-pass effect (FPE, eTICI [&ge;]2c-3), modified FPE (mFPE, eTICI [&ge;]2b-3), secondary occlusion, and complications. Results Of 1,824 passes in 995 consecutive patients (1,027 occlusions), 733 had imaging adequate for passive advancement assessment. Passive advancement occurred in 525/733 passes (71.6%), including to an arterial branch in 306/733 (41.7%). On per-pass analysis, passive advancement was associated with higher eTICI [&ge;]2b-3 (71.0% vs 19.7%) and eTICI [&ge;]2c-3 (57.5% vs 10.1%); advancement to a branch amplified these associations (90.5% vs 32.1% and 79.4% vs 18.7%; all p<0.001). Among 429 first passes, mFPE was 74.1% vs 10.8% and FPE 63.4% vs 7.5% with vs without passive advancement; rates reached 95.0% and 87.2%, respectively, at a branch point (all p<0.001). Passive advancement to a branch was inversely associated with secondary occlusion (13.3% vs 31.3%; p<0.001). On multivariable analysis, passive advancement independently predicted eTICI score, eTICI [&ge;]2b-3, and eTICI [&ge;]2c-3 (all p<0.001); final catheter position at a branch was the dominant independent predictor of FPE, mFPE, secondary occlusion, any complication, and intracranial complication on per-vessel analysis (all p[&le;]0.046). Conclusions Passive advancement is a prevalent physical phenomenon and an independent predictor of successful recanalization. When advancing to an arterial branch point, it is associated with mFPE >87%. Passive advancement should be a technical objective of aspiration thrombectomy.

Background: Unruptured intracranial aneurysms (UIAs) are increasingly identified incidentally, and management balances rupture risk against treatment risk. UIA diagnosis has been linked to psychological distress, but psychotropic medication initiation after UIA discovery has not been compared across the full UIA management spectrum. Methods: We conducted a retrospective cohort study using IBM MarketScan claims (CCAE, MDCD, and MDCR; 2009-2023) among adults with a UIA diagnosis, continuous enrollment for 365 days before and after the index date, and no SAH/rupture on or before the index date. We compared the prevalence of 6 mental-health diagnoses before versus after UIA discovery and used adjusted logistic regression to examine psychotropic medication initiation within 365 days by management strategy (untreated observation as the reference). Results: Among 54,945 patients (untreated, 78.5%; endovascular, 11.3%; clipping, 3.0%; other/uncertain, 7.2%), prevalence of every mental-health diagnosis was higher after UIA discovery, most for depression (+4.6 percentage points) and anxiety (+4.5 points). Medication initiation was most common for benzodiazepines (8.7%). Endovascular treatment was associated with higher adjusted odds of benzodiazepine (aOR, 1.21), SSRI (aOR, 1.20), and sedative-hypnotic (aOR, 1.25) initiation.Surgical clipping demonstrated the broadest association, with higher odds across 5 of 6 classes, including benzodiazepines (aOR, 1.71) and sedative-hypnotics (aOR, 1.86). Benzodiazepines had the lowest 1-year persistence (10.5%) despite being the most commonly initiated class. Findings were consistent across sensitivity analyses, with the exception of the increase in panic disorder, which was no longer observed after applying a 30-day post-index lag. Conclusions: Mental-health diagnoses and psychotropic medication initiation increased after UIA discovery, and medication initiation was most pronounced among patients treated with surgical clipping. These findings support psychological assessment as part of aneurysm management regardless of strategy.

Objectives: To develop and externally validate a wall-focused deep learning framework for identifying composite unstable intracranial aneurysm phenotypes on dual-phase high-resolution vessel wall imaging (HR-VWI), and to visualize model attention on the aneurysm wall surface. Methods: This retrospective multicenter study included patients with intracranial aneurysms who underwent both non-contrast and contrast-enhanced HR-VWI. Center 1 was used for model development and patient-level five-fold out-of-fold assessment, whereas Centers 2 and 3 served as independent external validation cohorts. For each aneurysm, dual-phase local wall patches and larger spatial context patches were generated. The Wall-Constrained Encoding Network (WCE-Net) extracted mask-constrained local wall features, and a transfer-learning U-Net with Nested Transformers (UNesT) branch extracted spatial context information. Branch outputs were fused by logit-level stacking. Model performance was evaluated using discrimination, calibration, and decision curve analysis. Three-dimensional gradient-weighted class activation mapping (Grad-CAM) responses were projected onto the reconstructed aneurysm wall surface and compared with HR-VWI surface signal intensity. Results: A total of 629 patients with 773 aneurysms were included. The final fusion model achieved areas under the receiver operating characteristic curves (AUCs) of 0.908, 0.857, and 0.855 in Center 1, external Center 2, and external Center 3, respectively. Corresponding Brier scores were 0.119, 0.153, and 0.150. Surface Grad-CAM showed partial spatial overlap between model-attention hotspots and high-signal HR-VWI regions. Conclusions: Dual-phase wall-focused local-context fusion showed feasibility for identifying composite unstable intracranial aneurysm phenotypes across centers. Surface Grad-CAM provided anatomically referenced visualization of model attention.

Background and Objectives: Recurrence following burr-hole drainage of chronic subdural haematoma (cSDH) occurs in 10-25% of cases, sustained by neovascularisation of the subdural neomembrane supplied by the middle meningeal artery (MMA). MMA embolisation reduces recurrence; whether incidental burr-hole intersection of MMA branches during drainage confers similar benefit is unknown. Methods: We performed a multicentre retrospective cohort study of consecutive adults undergoing burr-hole drainage for cSDH at two UK tertiary neurosurgical centres. Postoperative thin-slice CT was used to classify burr-hole intersection of the underlying MMA groove (no hit, distal-branch hit or main-branch hit) and measure perpendicular burr-hole-to-MMA-groove distance. Co-primary outcomes were radiological recurrence and recurrence requiring intervention. Patient-clustered multivariable logistic regression adjusted for prespecified clinical covariates and treating site. Results: 227 patients (284 operated hemispheres) were included. Radiological recurrence decreased from 34.4% with no branch hit to 22.9% with main-branch intersection, with the gradient confined predominantly to unilateral cSDH. Main-branch intersection was associated with lower adjusted odds of radiological recurrence in unilateral cSDH (adjusted OR 0.30, 95% CI 0.11- 0.81; P = .018), with a similar but non-significant association in the overall cohort (adjusted OR 0.53, 95% CI 0.26-1.07; P = .075). Burr-hole-to-MMA-groove distance demonstrated a more consistent association: in the overall cohort, each 5-mm increase independently increased the odds of radiological recurrence (adjusted OR 1.38, 95% CI 1.04-1.82; P = .025). In unilateral cSDH, each 5-mm increase was independently associated with both radiological recurrence (adjusted OR 1.45, 95% CI 1.03-2.04; P = .034) and recurrence requiring intervention (adjusted OR 1.52, 95% CI 1.05-2.20; P = .027). Conclusion: Main-branch intersection of the middle meningeal artery during routine burr-hole surgery is associated with lower recurrence of unilateral cSDH, while the accompanying burr-hole-to-MMA-groove distance gradient provides biologically plausible support for a dose-response relationship. Together, these findings provide mechanistic rationale for prospective evaluation of intentional neuronavigation-guided MMA targeting (BURR-MMA; NCT07549893).

Background and Purpose: Minor periprocedural ischemic events remain an important limitation of carotid artery stenting (CAS) compared with endarterectomy. Adverse-stent-vessel plaque interactions and in-stent plaque protrusion are proposed as contributing mechanisms. Selective intra-arterial three-dimensional rotational angiography (3DRA) provides high-resolution volumetric imaging directly in the endovascular suite without additional device crossing. Its incremental value for characterizing final implant quality and informing prognosis remains incompletely established. Objectives: We aim to determine whether adding 3DRA to conventional digital subtraction angiography (DSA): (1) improves expert characterization and reproducibility of Final Implant Quality (Imaging Domain); and (2) provides incremental prognostic information for 90-day Textbook Outcome failure beyond baseline clinical risk and conventional DSA (Prognostic Domain). Methods: SISYPHUS is a prospective, multicenter observational cohort of 67 patients undergoing elective CAS across three tertiary centers. Three blinded neuroradiologists will evaluate standardized image packages sequentially under DSA-only and DSA+3DRA conditions. Final Implant Quality will be assessed with a structured 10-item instrument: Q1-Q8 characterize specific findings, Q9 evaluates global implant adequacy (primary imaging variable), and Q10 captures technical image quality. Concealed repeat assessments will be performed in a randomized 17-patient subset for intra-reader reliability. The primary imaging estimand is the within-reader ordinal shift in Q9 after 3DRA is added, modeled with cumulative-link mixed-effects regression. The primary clinical endpoint is 90-day Textbook Outcome failure, integrating early neurological deterioration, major bleeding/procedural complications, stroke, TIA, MI, death, unplanned revascularization, and unplanned readmission within prespecified ascertainment windows. Incremental prognostic performance will be evaluated using nested ridge-penalized logistic regression models (M2 vs M3) with 2,000-resample bootstrap internal validation. Trial Status & Prospective Lock: Recruitment is complete (n=67), while protocol-defined follow-up remains ongoing. The Orthanc/OHIF reader study environment is being implemented; formal reader evaluations have not yet begun. The principal analytical architecture was prospectively locked in the Statistical Analysis Plan (SAP) Version 1.1.1 before formal inspection of reader results and before real-data prognostic model fitting.

Background Accurate prediction of 90-day outcomes following ischemic stroke is crucial for optimizing clinical strategies. This study aimed to systematically review and meta-analyze studies using deep learning (DL) and hand-crafted radiomics (HCR) models for predicting 90-day modified Rankin Scale (mRS) outcomes after ischemic stroke. Methods We followed the PRISMA guidelines for systematic reviews. Four databases (PubMed, Embase, Web of Science, and Cochrane Library) were searched comprehensively for studies published up to September 2025. Inclusion criteria encompassed original research focusing on ischemic stroke patients with mRS at 90 days as the primary outcome and predictive models utilizing imaging biomarkers from CT or MRI. Quality assessment of the included studies was conducted using the PROBAST and and METhodological RadiomICs Score (METRICS) tools. Results Seventeen studies were included in the quantitative meta-analysis. Models demonstrated good prognostic performance for 90-day outcomes, with pooled AUCs of 0.85 (95% CI: 0.80-0.86) for internal and 0.74 (95% CI: 0.67-0.89) for external validation sets, with no significant difference (p=0.42). Deep learning and hand-crafted radiomics models showed comparable diagnostic accuracy in the primary analysis (p=0.667); a difference in sensitivity favouring hand-crafted radiomics emerged only in a post-hoc analysis after exclusion of one outlier study. Models incorporating clinical variables significantly outperformed imaging-only models (p<0.01). CT- and MRI-based models showed similar performance. Treatment-specific analyses revealed higher sensitivity for IVT-based models and higher specificity for combined MT+IVT models. Conclusions DL and HCR models demonstrate robust potential for predicting 90-day outcomes in ischemic stroke. Future research should focus on standardizing model evaluation metrics and incorporating explainable AI techniques to improve clinical applicability.

Background: Telestroke evaluation and treatment programs are a promising option for geographically underserved populations. Adherence to guideline-based secondary prevention measures among telestroke programs remains understudied, particularly for patients with symptomatic intracranial atherosclerosis. The primary objective of this study was to evaluate whether routine telestroke consultation provides guideline-concordant management comparable to on-site vascular neurology consultation. Methods: This retrospective cohort review identified patients with stroke due to intracranial atherosclerosis within a single healthcare system comprising nine hospitals, including two comprehensive stroke centers with on-site stroke coverage and seven sites with remote telestroke coverage. Data was collected from January 2019 to December 2023. Adherence to guideline-based quality indicators was determined using four primary outcome measures including rates of permissive hypertension, high-intensity statin prescription at discharge, time to initiation of first antiplatelet medications, and appropriate antithrombotic therapy at discharge. Results: A total of 132 patients were included in the final analysis (median age, 69 years; 65 female [49.2], 67 male [50.8%]), with 87 patients evaluated and managed on-site and 45 via telestroke. Guideline adherence was similar between groups for permissive hypertension and discharge antithrombotic therapy. Patients managed via telestroke were more likely to receive high-intensity statins at discharge (absolute difference 27.1% (95% CI 11.4, 42.8)) and received antiplatelet therapy earlier than patients managed on-site. Conclusion: In this multisite, single-system cohort, routine telestroke consultation was associated with similar or greater adherence to selected guideline-based management measures compared with on-site vascular neurology consultation.

Background Spontaneous intracerebral hemorrhage (ICH) is the most devastating type of stroke but lacks the established time-critical treatment guidelines available for acute ischemic stroke. This study investigated the impact of Code Stroke activation and warfarin use on anticoagulation reversal times to identify opportunities for quality improvement. Methods We retrospectively assessed patients with anticoagulation-associated ICH admitted to our medical center between January 1, 2020, and December 31, 2025. Patients with warfarin- or direct oral anticoagulant (DOAC)-associated ICH were identified from our ICH clinical trial screening log, Vizient, and AHA's Get With The Guidelines-Stroke registry. Code Stroke activation, warfarin or DOAC use, anticoagulation reversal times, causes of delay, and clinical outcomes at hospital discharge were analyzed. Results Of 892 ICH admissions, 50 patients had confirmed anticoagulation-associated ICH. Among those who underwent reversed at our center (n=34), Code Stroke activation (n=24) significantly reduced door-to-CT time (16.5 [12.8-22.0] vs 172.5 [49.0-261.5] minutes, p <0.001), reversal agent order-to-needle time (37.5 [24.7-56.9] vs 57.0 [39.0-85.0] minutes, p <0.001), and door-to-treatment (DTT) time (64 [48-98] vs 277 [159-305] minutes, p <0.001) compared to non-activation (n=10). Conversely, warfarin use was associated with higher international normalized ratios (INR) (2.7 [2.2-3.6] vs 1.3 [1.2-1.9], p =0.003) and significantly longer DTT time (95 [51-108] vs 64 [48-77] minutes, p =0.007). Primary DTT delays stemmed from the absence of a time-critical treatment protocol, weight-based dosing for 4F-PCC, waiting for INR results, and a lack of Code Stroke activation for patients with mild symptoms, trauma or unexplained unresponsiveness. Conclusions Our findings suggest that Code Stroke activation for all suspected cases of ICH, a time-critical emergency department algorithm targeting a DTT time of less than 60 minutes, and immediate anticoagulation reversal with fixed-dose 4F-PCC without waiting for INR results may optimize the acute management of anticoagulation-associated ICH.

Purpose: To develop an automated pipeline (PERADS.net) that segments acute pulmonary embolism on CT pulmonary angiography, assigns a Pulmonary Embolism Reporting and Data System (PE-RADS) grade with named anatomic localization, and measures the right-to-left ventricular (RV/LV) diameter ratio, and to assess radiologist agreement. Materials and Methods: In this retrospective study, 120 CT pulmonary angiograms (70 peripheral, 35 central, 15 negative) from the public RSNA Pulmonary Embolism CT dataset were analyzed. A two-channel five-fold nnU-Net ensemble segmented the embolus; the pulmonary arterial tree was reduced to a branching graph, and the grade was set by the most proximal level with at least 1% of embolic volume. Three radiologists, blinded to the algorithm-assigned grade, independently assigned grades and rated RV/LV plausibility. Agreement was assessed with percent agreement and Cohen or Fleiss kappa on five-grade and grouped scales (grade 0 versus 1-2 versus 3-4). The automated ratio was compared with the dataset's binary RV/LV label in 2119 examinations. Results: Agreement between the algorithm and three-radiologist consensus (n = 119) was 60.5% (kappa, 0.38) for individual grades and 90.8% (kappa, 0.74; 95% CI: 0.59, 0.87) for the grouped scale; 34 of 47 discordant examinations fell within grades 3-4. As a fourth reader, the algorithm matched grouped-scale interobserver agreement (mean kappa, 0.62 versus 0.67). Radiologists showed no agreement rating RV/LV plausibility as favorable or incorrect (Fleiss kappa, -0.00), whereas the automated ratio agreed with the external label (kappa, 0.49), overestimating strain 3.1:1. Conclusion: Automated PE-RADS grading agreed with radiologist consensus comparably to a fourth reader on the grouped scale.

BACKGROUND AND PURPOSE: Measured intracranial vessel dimensions guide device selection in cerebrovascular intervention, yet accuracy depends on imaging modality, luminal contrast concentration, and the lumen-edge detection criteria. Prior accuracy studies benchmark one angiographic modality against another rather than physical ground truth. This study quantifies accuracy of CT angiography (CTA), 3D rotational angiography (3DRA), and 2D digital subtraction angiography (DSA) against a phantom of tubular contrast-filled structures serving as surrogates for intracranial vessels. MATERIALS AND METHODS: Phantoms with cylindrical lumen diameters 1.2-8.5 mm at graded iodinated contrast concentrations (6.25-100%) were imaged with clinical devices in air and a tissue-equivalent gel surround. Tubular cross-sections perpendicular to centerlines were measured by maximum-gradient, full-width-half-maximum (FWHM), and fixed-Hounsfield criteria and compared with physical phantom measurements using mixed-effects models. RESULTS: Across 1682 cross-sections (73 lumens), all modalities recovered true diameter within ~0.5 mm but consistently measured larger than the true dimensions. Over-measurement occurred minimally in the 2-5 mm range, maximally at the extremes of caliber and contrast concentration. 3DRA was modestly closer to physical phantom measurements than CTA (gradient bias +0.40 vs +0.60 mm). Maximum-gradient edge over-measured diameters versus the conventionally preferred FWHM, with the latter carrying larger, more concentration-sensitive bias. Fixed-HU thresholds were concentration-biased on CTA and unusable on 3DRA. 2D DSA, currently the clinical reference standard, was itself biased in analysis of its auto-calibrated measurements, over-measuring large lumens, under-measuring small lumens 1.5 mm, and reading larger frontally than laterally through magnification. CONCLUSIONS: Conventional CTA, 3DRA, and 2D DSA each measure intracranial-scale caliber lumens within ~0.5 mm but with consistent bias. Maximum-gradient lumen edge detection minimizes bias and outperforms FWHM, while fixed-Hounsfield contour tracing is unreliable, particularly on 3DRA. Characterizing these error modes provides a calibration basis for automated vessel-measurement platforms.

Optimal blood pressure management after thrombectomy remains uncertain, and individualized autoregulation-based targets typically require continuous neuromonitoring. We developed an angiography-derived autoregulatory metric using intraprocedural data and applied it retrospectively to a single-center cohort of patients who underwent thrombectomy for acute stroke. From 62 patients with 3-month functional outcomes, greater time within the predicted autoregulatory range during the first 24 hours after thrombectomy was independently associated with improved outcome after adjustment for covariates (odds ratio per 10% increase, 1.86; 95% CI, 1.31-2.66; P = .0006). These findings support routine angiography as a potential source of early, patient-specific hemodynamic targets after thrombectomy.

Objectives: Aneurysmal subarachnoid haemorrhage is a life-threatening emergency that commonly presents with a sudden, severe headache. The diagnosis is usually confirmed on CT imaging, however a small subset of patients demonstrate normal imaging, particularly if presentation is delayed - in which case spectrophotometric analysis of cerebrospinal fluid (CSF) is undertaken. Nevertheless, thunderclap headache is a common presentation and the vast majority of investigated patients do not have aneurysmal subarachnoid haemorrhage. This ten-year service evaluation at a tertiary neurosurgery centre aims to estimate the utility of lumbar puncture in the diagnostic work-up of these patients. Methods: All instances of CSF spectrophotometry between 01/01/2011 and 31/12/2020 were evaluated. Clinical records of patients with positive spectrophotometry were analysed. A second method identified all coded diagnoses of non-traumatic subarachnoid haemorrhage over the same time period, with review of clinical records in cases of negative imaging. Results: Of 2158 instances of CSF spectrophotometry performed at the tertiary neurosurgery centre, four aneurysms were identified and treated by coiling or clipping, resulting in a number needed to treat of 540 patients to diagnose one case of aneurysmal subarachnoid haemorrhage. Of 648 patients with a coded diagnosis of non-traumatic subarachnoid haemorrhage (including local patients and transfers from satellite hospitals), 27 patients displayed initial negative imaging, of which 9 were found to have aneurysms and underwent neuro-intervention. Lumbar puncture was instrumental in the diagnosis and led to intervention in three patients identified by this method. Conclusion: CSF analysis resulted in diagnosis and intervention for missed (CT-negative) aneurysmal subarachnoid haemorrhage in approximately 1/540 tested patients. The estimated yield in a real-world setting may be useful for clinicians or provide a basis for discussion when counselling patients on benefit and risk.