Adnan H. Siddiqui

BACKGROUND AND OBJECTIVES: The Woven Endobridge (WEB) and the Contour Neurovascular System (Contour) are both intrasaccular devices used to treat cerebral aneurysms. We compared outcomes of these 2 devices using data from 2 large registries. METHODS: Data were sourced from the WorldWideWEB Consortium, which included 1363 cases treated with WEB from 2017, and a registry of 277 Contour cases from 10 European centers starting the same year. Patient demographics, aneurysm characteristics, procedural specifics, and outcomes were analyzed. Propensity score matching was applied for comparison. RESULTS: Before matching, the Contour group had more men (37.9% vs 30.8%), more asymptomatic cases (83.4% vs 70.3%), and fewer acute subarachnoid hemorrhage cases (10.8% vs 26.2%). After matching, no significant differences were found in demographics or aneurysm characteristics between groups. The median age was 60 years, and median aneurysm dimensions were comparable. Logistic regression showed no significant differences between WEB and Contour in achieving complete occlusion (odds ratio [OR] = 1.01, 95% CI, 0.67-1.52, P = .971), adequate occlusion (OR = 0.85, 95% CI, 0.41-1.76, P = .665), or achieving modified Rankin Scale 0 to 2 at last follow-up (OR = 0.48, 95% CI, 0.21-1.02, P = .064). Retreatment (OR = 2.23, P = .086), thromboembolic complications (OR = 0.75, P = .452), and adjunctive treatment use (OR = 1.93, P = .141) were also similar. CONCLUSION: The WEB and Contour demonstrated comparable clinical and angiographic outcomes in this large multicenter study comprised majority small, asymptomatic cerebral aneurysms.

Introduction: Ruptured intracranial aneurysms (RIAs) are a significant cause of morbidity and mortality. While individual-level risk factors for aneurysmal subarachnoid hemorrhage (aSAH) are well established, the influence of meteorological variables has been widely debated but remains unclear. Methods: We retrospectively analyzed 1504 endovascularly treated intracranial aneurysm cases from two stroke centers (2018 to 2024). We matched daily weather data to presentation dates. We used variance inflation factor (VIF) analysis to remove collinear features. Multivariable logistic regression models were adjusted for age and sex. We developed extreme gradient boosting (XGBoost) models using weather variables alone and in combination with demographic covariates (age, sex, race, smoking status, and family history). Results: Of 1504 cases, 377 (25.1%) presented with rupture. In univariate logistic regression, greater humidity (odds ratio [OR] 0.988 per 1% relative humidity, 95% confidence interval [CI] 0.979 to 0.998, p = 0.0135) and greater ultraviolet (UV) index (OR 0.951 per index unit, 95% CI 0.914 to 0.990, p = 0.0146) were associated with reduced odds of rupture, whereas greater snow depth (OR 1.360 per inch, 95% CI 1.068 to 1.731, p = 0.0126) and advanced moon phase (OR 1.589 per full lunar cycle, 95% CI 1.064 to 2.373, p = 0.0237) were associated with increased odds. On multivariable analysis, only female sex remained protective (OR 0.605, 95% CI 0.386 to 0.949, p = 0.0285), and greater sea level pressure trended toward lower odds of rupture without reaching significance (OR 0.962, p = 0.0523). Findings were consistent in a full-cohort, center-adjusted sensitivity analysis. The weather-only XGBoost model yielded an area under the receiver operating characteristic curve (AUC) of 0.560 and a recall of 78%, which improved to an AUC of 0.590 and a recall of 83% after adding demographic variables. SHapley Additive exPlanations (SHAP) analysis identified precipitation and cloud cover as key meteorological features. Conclusions: Several weather variables correlated with rupture risk in univariate analysis, but overall predictive value was limited. Machine learning improved sensitivity while confirming patient features as the dominant contributors. Weather on the day of presentation was not significantly associated with rupture.

Background: Neurointerventionalists performing stent assisted coil embolization for intracranial aneurysms use Neuroform Atlas stents (Stryker) for their low metal coverage, deployment ease, and lower thromboembolic risk, although low profile visualized intraluminal support (LVIS) and LVIS Jr stents (Terumo Neuro) offer better wall apposition and high metal coverage, potentially promoting flow diversion and endothelialization. The next generation LVIS Evolution (LVIS EVO; Terumo Neuro) adds enhanced visibility, improved resheathability, and even higher metal coverage to address earlier limitations of LVIS and LVIS Jr. We evaluated the performance and complications of these devices. Methods: PubMed and Embase were searched from 1 January 2017 to 31 July 2025 to identify studies comparing Atlas assisted coil embolization (AACE) versus LVIS/LVIS Jr assisted coil embolization (LACE), and single arm LVIS EVO assisted coil embolization (LeACE) studies. Meta-analyses were performed to compare baselines, procedural considerations, and occlusion rates. Results: We included five studies comparing 504 patients treated with AACE and 579 patients with LACE, and 12 studies evaluating LeACE (575 patients). Fewer aneurysms were ruptured at presentation in the AACE group than in the LACE (OR 0.09; P<0.01) and LeACE (0.7% vs 15.2%; P<0.01) groups. Comparable technical failure rates were found between AACE and LeACE (1.8% vs 5.4%; P=0.15), contrasting with the superiority of AACE over LACE (OR 0.14; P<0.01). AACE resulted in higher immediate adequate occlusion than LACE (OR 1.62; P=0.02), but comparable with LeACE (83% vs 90.8%; P=0.28). Follow-up complete occlusion rates were similar between AACE and LACE (OR 1.31; P=0.16) and between AACE and LeACE (82.4% vs 81.2%; P=0.86). Conclusions: The superior outcomes of the Atlas over LVIS/LVIS Jr were matched by the LVIS EVO. Thromboembolic complications occurred more frequently with the LVIS EVO.

BACKGROUND: The impact of internal carotid artery tortuosity on achieving first-pass effect in mechanical thrombectomy has been described; however, middle cerebral artery (MCA) tortuosity remains understudied. We investigated the association of MCA tortuosity with radiographic and functional outcome using quantitative and qualitative measures. METHODS: The ARISE II study (Analysis of Revascularization in Ischemic Stroke With EmboTrap) was used to identify patients with anterior circulation stroke. MCA tortuosity was calculated using the Inflection Count Metric by 2 readers blinded to the angiographic/clinical outcomes. The total cohort was trichotomized into 3 groups (A, B, and C) based on M1 tortuosity tertiles, with group A representing the lowest tertile and group C representing the highest tertile. The primary efficacy end point was the achievement of first-pass expanded Thrombolysis in Cerebral Ischemia reperfusion ≥2c. A good functional outcome was defined as a 90-day modified Rankin Scale score of 0 to 2. Baseline and procedural data were compared between groups. RESULTS: A total of 168 patients with M1 or M2 occlusion and measurable MCA tortuosity were identified. Patients in group C were more likely to have renal disease and hyperlipidemia, whereas patients in group A were more likely to have hypertension ( P P =0.024). The rate of final expanded Thrombolysis in Cerebral Ischemia reperfusion ≥2c was higher in group A (87.5%) versus in groups B and C (77.8% and 66%, respectively; P =0.026); achieving modified Rankin Scale score of 0 to 2 was more likely in group A (77.8%) versus in groups B and C (74.5% and 52.7%, respectively; P =0.008). There were no differences in distal emboli or symptomatic intracranial hemorrhage. First-pass effect and angiographic outcomes were consistent with standard angle of curvature tortuosity. CONCLUSIONS: Patients with higher MCA tortuosity were less likely to achieve first-pass effect, successful reperfusion, and good functional outcome at 90 days postmechanical thrombectomy for acute ischemic stroke. REGISTRATION: URL: http://clinicaltrials.gov ; Unique identifier: NCT02488915.

BACKGROUND: The EMBOLISE trial (The Embolization of the Middle Meningeal Artery With Onyx Liquid Embolic System in the Treatment of Subacute and Chronic Subdural Hematoma) demonstrated that middle meningeal artery embolization as an adjunct to surgical drainage reduces recurrence of symptomatic subacute and chronic subdural hematomas. We performed a subgroup analysis of the EMBOLISE surgical cohort to determine how the timing of embolization relative to surgery impacted various outcomes. METHODS: We performed a post hoc subgroup analysis to examine the association of the timing of embolization relative to surgery with the primary end point (hematoma reoperation within 90 days), secondary end points (clinical and radiographic outcomes), and safety end points (serious adverse events, neurological death, all-cause death, and stroke). RESULTS: Middle meningeal artery embolization before surgery (embolization-first group) and middle meningeal artery embolization after surgery (surgery-first group) were performed in 107 and 78 patients, respectively. Demographics and baseline clinical characteristics of the 2 groups were similar. The core laboratory confirmed the procedure to be successful in all patients with similar rates of distal penetration of Onyx into middle meningeal artery branches at the end of the embolization procedure in both groups (49.5% and 48.7%, respectively, P >0.99). Six of 103 patients in the embolization-first group (5.8%) and none in the surgery-first group needed reoperation within 90 days (analysis with observed data, P =0.08). Hematoma volumes at 90 and 180 days were similar except for lower hematoma thickness in the surgery-first group (2.3±3.0 mm versus 4.4±5.6 mm, P =0.03) at 180 days. Clinical and safety outcomes at 30, 90, and 180 days were similar. CONCLUSIONS: Performing surgical drainage before embolization in patients with subacute and chronic subdural hematomas may help minimize treatment failures and enhance hematoma resolution. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04402632.

BACKGROUND: Intraventricular hemorrhage and subarachnoid hemorrhage are associated with neuroinflammation and increased morbidity and mortality. Rapid clearance of blood from the cerebrospinal fluid space may mitigate neuroinflammatory cascades and improve clinical outcomes. This systematic review and meta-analysis aimed to compare the clinical effectiveness of active cerebrospinal fluid exchange, including neuroendoscopic lavage and IRRAflow systems, versus external ventricular drainage in patients with intraventricular hemorrhage or subarachnoid hemorrhage. METHODS: The study followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and thoroughly assessed databases, including PubMed, Embase, Scopus, Cochrane, and Web of Science, up to September 18, 2025. Statistical analysis, both fixed-effect and random-effect model analyses, was performed by the Comprehensive Meta-Analysis software. In addition, the Cochran Q test was conducted to determine the statistical heterogeneity. In terms of low heterogeneity, the fixed-effect model is reported. RESULTS: This review included 7 studies with a total sample size of 834. Our analysis showed that active cerebrospinal fluid exchange was associated with significantly higher hematoma clearance (odds ratio, 2.72 [95% CI, 1.22–6.08]; P =0.015), better functional outcomes (odds ratio, 1.66 [95% CI, 1.12–2.48]; P =0.012), lower shunt dependency (odds ratio, 0.22 [95% CI, 0.10–0.50]; P P <0.001). Subgroup analysis showed that neuroendoscopic lavage was most effective for hematoma clearance, while IRRAflow reduced infection rates. Also, younger patients had better neurological recovery. CONCLUSIONS: Active cerebrospinal fluid exchange techniques demonstrated superior outcomes over external ventricular drainage in managing intraventricular hemorrhage and subarachnoid hemorrhage, particularly in clot resolution and neurological recovery. Large-scale trials are warranted.

BACKGROUND: Symptomatic intracranial atherosclerotic disease can be managed with medical therapy, risk factor control, angioplasty, and stenting. The Wingspan stent demonstrated limited efficacy and higher adverse outcomes than medical management in the SAMMPRIS trial (Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis). Drug-eluting stents, including the Resolute Onyx Zotarolimus-eluting stent, have demonstrated superior outcomes beyond 1 year. This study assessed outcomes at ≥24 months after stenting. METHODS: This retrospective multicenter study compared patients diagnosed with severe symptomatic intracranial atherosclerotic disease who underwent Resolute Onyx Zotarolimus-eluting stent stenting between March 2018 and May 2021 with patients from the percutaneous angioplasty and stenting and the aggressive medical management arms of the SAMMPRIS trial. Individuals who remained alive, stroke-free, and under follow-up at 24 months were included. Propensity score matching was used to align the 3 arms, and landmark analysis using inverse probability weighting, accounting for differential survival to 24 months, was used as complementary sensitivity analysis. The primary outcomes measured were postlandmark (ie, 24 months) stroke recurrence, intracranial hemorrhage, and all-cause mortality. RESULTS: After applying the 24-month landmark and propensity score matching, 204 patients (68 per arm) were eligible (median follow-up, 36 months). Unweighted rates of stroke ( P =0.147), intracranial hemorrhage ( P =0.362), and mortality ( P =0.168) did not differ significantly among groups. Weighted multivariable logistic and Cox regression analyses, adjusting for residual postmatch differences, similarly showed no significant differences in stroke recurrence. Kaplan-Meier analysis did not demonstrate a significant difference in overall survival across the 3 arms (log-rank P =0.139). CONCLUSIONS: Although previous studies have demonstrated the superiority of the Resolute Onyx Zotarolimus-eluting stent compared with the Wingspan system and aggressive medical management for the treatment of severe symptomatic intracranial atherosclerotic disease, the present landmark analysis suggests that these benefits may not consistently extend beyond 24 months. One speculative explanation is that the drug elution–related benefit of the Resolute Onyx Zotarolimus-eluting stent may attenuate over time, but this was not directly assessed in the present study. Prospective, controlled trials are necessary to confirm the implications of our long-term findings.

BACKGROUND: The optimal management of isolated posterior cerebral artery occlusion (iPCAO) remains unclear. We investigated whether baseline perfusion imaging parameters are associated with clinical outcomes and whether they modify the association between endovascular therapy (EVT) and outcomes in iPCAO. METHODS: This prespecified secondary analysis of the international, multicenter, observational PLATO (Posterior Cerebral Artery Occlusion) registry (35 centers, 10 countries, 2015–2025) included consecutive adults with unilateral iPCAO and baseline perfusion imaging (computed tomography or magnetic resonance imaging) with reconstructed parameters. The primary end point was an excellent 90-day outcome (modified Rankin Scale score, 0–1). Perfusion parameters included hypoperfusion volume, infarct core volume, and mismatch ratio. The primary analysis used multivariable mixed-effects regression models (center as random effect) to assess associations between perfusion parameters and outcomes, adjusting for age, sex, treatment year, prestroke modified Rankin Scale score, baseline National Institutes of Health Stroke Scale score, diabetes, stroke cause, posterior circulation Acute Stroke Prognosis Early Computed Tomography Score, occlusion site, intravenous thrombolysis, and onset-to-door time. To test whether the association between EVT and outcomes varies according to baseline perfusion parameters, we evaluated treatment-by-perfusion interactions by including interaction terms (treatment×perfusion parameter) in inverse probability of treatment weighting–adjusted models, with results expressed as ratios of odds ratios (ORs). RESULTS: Of 1811 patients with iPCAO, 443 met inclusion criteria (median age, 74 years; 41.8% female). Larger hypoperfusion volume was associated with lower odds of excellent outcome (adjusted OR, 0.72 [95% CI, 0.58–0.89] per 1-unit increase in natural logarithm–transformed volume). No interaction between perfusion parameters and EVT was observed for the primary outcome. However, increasing core volume was associated with a progressively less favorable modified Rankin Scale score shift (ratio of OR, 0.66 [95% CI, 0.48–0.90]; P _interaction =0.009) and higher mortality (ratio of OR, 1.82 [95% CI, 1.10–3.03]; P _interaction =0.021) with EVT compared with medical management. Increasing hypoperfusion volume was associated with a higher risk of symptomatic intracranial hemorrhage with EVT (ratio of OR, 10.15 [95% CI, 1.06–96.93]; P _interaction =0.044). CONCLUSIONS: In iPCAO, perfusion imaging provides independent prognostic information but does not identify patients with potential benefit from EVT and may instead indicate those at higher procedural risk. REGISTRATION: URL: https://osf.io/62mwt ; Unique identifier: NCT05291637.