Brinjikji, Waleed

Abstract Stroke thrombi are heterogeneous; their composition influences their mechanical properties, including stiffness, elasticity, and adhesiveness, which in turn affect their response to therapy. Systemic characterization of the thrombi components could help select therapeutic techniques and anticipate outcomes. We conducted a systematic review and meta-analysis to evaluate associations between thrombi composition and angiographic and functional outcomes in acute ischemic stroke (AIS). Up to May 2025, relevant studies were sourced from four databases: PubMed, Web of Science, Scopus, and Embase. We included cohort studies whose populations are patients with AIS in relation to thrombi composition. Thirty-six studies involving 5,462 patients matched our eligibility criteria. Angiographic success (Thrombolysis in Cerebral Infarction ≥ 2b/3) did not differ significantly between red blood cell (RBC)-rich and fibrin-rich thrombi (risk ratio [RR] 1.02, 95% confidence interval [CI] 0.85–1.22; p = 0.84; I 2 = 63.8%; very low certainty). However, thrombi from patients with good angiographic outcomes had a significantly higher RBC content compared to patients with poor outcomes (mean difference = 7.22%, 95% CI 3.31–11.13; p < 0.001; low certainty). No significant difference was observed between RBC-rich and fibrin-rich thrombi regarding functional independence at 90 days (modified Rankin Scale 0–2) (RR = 1.22, 95% CI 0.73–2.05; p = 0.31; low certainty). While RBC-rich thrombi are associated with more favorable angiographic performance, thrombus composition alone does not predict functional outcomes. Stroke outcomes remain multifactorial, dominated by time to reperfusion, collateral circulation, and baseline severity. Preinterventional assessment of clot composition via imaging or biomarkers may support individualized therapy but should complement, not replace, other prognostic determinants.

Cerebrospinal fluid (CSF)–venous fistulas are an increasingly recognized source of spontaneous intracranial hypotension, for which endovascular embolization has emerged as an effective treatment option.1–3 Advances in diagnostic imaging have improved detection of CSF–venous fistulas throughout the cervical, thoracic, and lumbar spine; however, identification of lesions at the cranial and caudal extremes of the spine remains challenging.4 In video 1, we present the novel case of an anterior condylar confluence CSF–venous fistula arising from a hypoglossal canal nerve root sleeve diverticulum. We demonstrate the diagnostic evaluation, preprocedural planning, and transvenous embolization of the fistula using the pressure cooker technique, highlighting key technical considerations for navigating this uncommon venous anatomy. Finally, we review the patient’s postprocedural course and imaging findings demonstrating radiographic resolution of spontaneous intracranial hypotension. Video 1 Endovascular embolization of a cerebrospinal fluid–venous fistula arising from a hypoglossal canal nerve root sleeve diverticulum using a transvenous pressure cooker technique.

Background Randomized trials have shown equivocal outcomes between a direct aspiration as first-pass technique (ADAPT) and stent retriever (SR) stroke thrombectomy, yet whether specific patient subgroups benefit differentially from one technique over the other remains unknown. Methods In this retrospective multicenter cohort study, patients with large vessel occlusion were included, and those who underwent ADAPT versus SR first-pass thrombectomy (either as standalone or combined with aspiration) were compared. The primary outcome was a composite of first-pass effect (FPE, modified Thrombolysis In Cerebral Infarction (mTICI) 2c or better with one attempt) with no symptomatic intracranial hemorrhage (sICH). A causal forest model was used to estimate the conditional average treatment effect (CATE) for each patient, with larger CATEs indicating that ADAPT is expected to be more advantageous. Patients were stratified by CATEs, and outcomes were compared between treatment groups. Results Among 6700 included patients, ADAPT (n=3695, 55%) was associated with a higher rate of FPE with no sICH (39.9% vs 26.9%; adjusted OR (aOR) 2.07, 95% CI 1.77 to 2.41, P<0.001). The causal forest identified significant treatment effect heterogeneity (interaction P<0.001), where ADAPT was more advantageous in more recent years and among patients with M1 occlusions presenting in earlier time windows. Low-CATE patients showed no statistically significant difference between techniques (aOR 0.91, 95% CI 0.57 to 1.45, P=0.70), while medium- and high-CATE patients demonstrated progressively larger ADAPT advantages (aOR 2.06, 95% CI 1.67 to 2.55, and aOR 2.99, 95% CI 2.24 to 3.98, respectively, both P<0.001). Conclusions ADAPT may be superior to SR for a majority of patients, particularly in recent years, and among patients with M1 occlusions presenting in earlier time windows.

Background: Pulsatile tinnitus (PT) is frequently caused by venous sinus stenosis and may be associated with idiopathic intracranial hypertension (IIH). Venous sinus stenting (VSS) directly addresses venous outflow obstruction and has emerged as a therapeutic option; however, outcome data remain heterogeneous. We performed an updated systematic review and meta-analysis to evaluate the efficacy and durability of VSS for PT and to compare outcomes between IIH-associated and isolated PT. Methods: MEDLINE, Scopus, and Web of Science were searched from inception through December 2025 following PRISMA guidelines. Clinical studies reporting PT outcomes after VSS were included. Random-effects meta-analyses of proportions were conducted to estimate pooled rates of overall improvement, complete resolution, and recurrence. Prespecified subgroup analyses compared IIH versus isolated PT. Results: Thirty-two studies comprising 850 patients were included (641 with IIH; 209 with isolated PT). Venous sinus stenosis accounted for 90.3% of treated etiologies. The pooled rate of overall PT improvement was 89.8% (95% CI, 85.5-92.9). Complete resolution occurred in 87.1% (95% CI, 82.5-90.6). Recurrence at last follow-up was 10.9% (95% CI, 8.3-14.2). Improvement and complete resolution rates did not differ significantly between IIH and isolated PT. Recurrence was higher in IIH (12.0%) than in isolated PT (5.7%), without reaching statistical significance. Conclusions: VSS is associated with high rates of PT improvement and complete resolution with low recurrence. Recurrence trends appear higher in IIH, suggesting underlying pathophysiology may influence durability.

OBJECTIVE Endovascular thrombectomy (EVT) for acute large-vessel occlusion stroke is well established, yet its role in patients presenting with minor stroke symptoms (National Institutes of Health Stroke Scale [NIHSS] score < 6) remains unclear. Prior studies have not accounted for intraprocedural factors that may influence outcomes in this subgroup. METHODS The authors analyzed 5693 patients from the STAR (Stroke and Thrombectomy and Aneurysm Registry), including 398 with low NIHSS scores, to evaluate the association between procedure time (PT) and outcomes. Among patients with low NIHSS scores, propensity score matching was used to compare outcomes between those with PT ≤ 35 versus > 35 minutes, a cutoff defined using receiver operating characteristic curve analysis. The authors performed a meta-analysis of studies reporting best medical management (BMM) outcomes in patients with low NIHSS scores. To compare these with EVT-treated patients, a matched BMM comparator cohort using stratification on pooled baseline characteristics was constructed. Outcomes included 90-day functional independence (modified Rankin Scale [mRS] scores 0–2), intracranial hemorrhage, and mortality. RESULTS PT had a stronger negative effect on outcomes in patients with low NIHSS scores compared with those with high scores, with a steeper decline in functional independence per minute of PT (slope: –0.45% vs –0.21%; p = 0.03 for interaction). Among patients with low scores, PT ≤ 35 minutes was associated with higher 90-day functional independence compared with the propensity score–matching cohort with PT > 35 minutes (82.6% vs 59.0%, p < 0.001). When benchmarked against BMM (75.2% mRS scores 0–2), patients undergoing EVT within 35 minutes had superior outcomes (85.1%, p = 0.047). In contrast, EVT with PT > 35 minutes resulted in worse outcomes than BMM (mRS scores 0–2: 59.8%, p = 0.008). The number needed to treat for PT ≤ 35 minutes was 10, whereas PT > 35 minutes yielded a number needed to harm of 6. CONCLUSIONS PT critically modulates the benefit of EVT in minor stroke. While efficient EVT yields better outcomes than BMM, prolonged procedures are associated with harm. These findings may explain prior inconsistent evidence on EVT in patients with low NIHSS scores and underscore the need to individualize procedural thresholds in this population.

OBJECTIVE The objective was to evaluate the trajectories of hematoma resolution and functional improvement after middle meningeal artery embolization (MMAE) for chronic subdural hematoma (cSDH), model the temporal pattern of cSDH resolution, and identify factors associated with favorable outcomes. METHODS This real-world multicenter retrospective study included cSDH patients treated with MMAE at 24 centers between 2019 and 2024. Hematoma thickness was measured at baseline and at follow-up intervals (1–4 weeks, 1–3 months, 3–6 months, 6–12 months, and > 12 months after embolization). Resolution patterns were modeled using exponential decay functions. Modified Rankin Scale (mRS) scores assessed functional outcomes. Good functional outcome was defined as mRS score ≤ 2. Resolution patterns were modeled using exponential decay functions to estimate time to 50% and 80% reduction. Patients were categorized as complete resolution (≥ 99%) or by quartile of the remaining distribution (substantial [73%–98%], moderate [53%–73%], partial [27%–53%], minimal [< 27%]). The primary outcome was good functional status (mRS score ≤ 2). RESULTS The authors analyzed a total of 1781 patients with 2295 cSDHs who underwent MMAE. The mean ± SD age was 72.8 ± 12.4 years and 68.1% of patients were male. The initial mean hematoma thickness was 15.31 ± 6.53 mm, decreasing to 5.24 ± 5.91 mm at final follow-up (mean reduction 64.3% ± 42.1%). Resolution followed an exponential decay pattern, with an estimated time to 50% reduction of 1.8 months and to 80% reduction of 8.9 months. Complete resolution occurred in 1031 of 2224 patients (46.4%) with complete follow-up. The median (IQR) mRS score improved from 1 (0–3) at baseline to 0 (0–2) at > 12 months. Good functional outcomes were more common in patients with complete versus minimal resolution (68.9% vs 35.0%, p < 0.001). Achieving ≥ 73% resolution within 90 days was associated with better outcomes (good outcome in 76.9% of those with ≥ 73% resolution vs 67.3% in those without, p < 0.001). Neurological deterioration was the strongest predictor of lack of good outcome (23.7% in patients with neurological deterioration vs 82.4% without, p < 0.001). CONCLUSIONS After MMAE for cSDH, reduction in hematoma thickness follows a predictable exponential decay pattern. Greater extent (≥ 80%) and faster timing (within 90 days) of resolution are valuable prognostic indicators. Functional outcomes improve progressively through 6–12 months after the procedure. The relationship between resolution extent and functional outcomes provides quantitative benchmarks for evaluating treatment response.

Background Large vessel occlusion (LVO) stroke is associated with a high risk of permanent disability. There are no reliable tools providing periprocedural information on clot characteristics, such as composition and length, that may impact first pass effect, which has been shown to improve functional outcomes. In the first study of a novel technology, we evaluated whether the Clotild Smart Guidewire System (Clotild), an impedance-based device, can provide in situ information on clot characteristics during a mechanical thrombectomy procedure. Methods This is the first-in-human, international, multicentric, single-arm trial involving LVO stroke patients. Of 45 enrolled subjects, 41 constituted the safety population; 39 was the per protocol population, of which 26 subjects with complete impedance data comprised the performance population. The latter was divided into development (11 subjects) and validation (15 subjects) populations for prediction model development and assessment. The safety endpoint assessed Clotild-related intracranial vessel perforation/dissection. Performance endpoints evaluated Clotild’s ability to perform classification of impedance measurements distinguishing substantial versus negligible local content in red blood cells (RBCs) and platelets, to detect the arterial wall and the distal end of the clot. Results The safety endpoint was met in all subjects. Performance analysis comparing the agreement between Clotild’s output and impedance experts’ readings showed an area under the receiver operating characteristic curve (AUC) of 0.97 (95% CI 0.93 to 0.99) for RBC, and 0.94 (95% CI 0.89 to 0.98) for platelet clot composition. Regarding detection, Clotild’s performance showed an AUC of 0.69 (95% CI 0.59 to 0.77) for the arterial wall, and 0.83 (95% CI 0.59 to 1.00) for the distal end of the clot. Conclusions Clotild was proven safe to acquire impedance data and to provide information on in situ clot characteristics in large vessel occlusions.

Abstract Purpose Although the Woven EndoBridge (WEB) device is increasingly used for the treatment of wide-neck intracranial aneurysms, including in the acute rupture setting, comparative evidence assessing the impact of rupture status remains limited. This study compared angiographic, safety, and clinical outcomes between ruptured and unruptured intracranial aneurysms treated with WEB. Methods We conducted a retrospective analysis of prospectively collected data from the multicenter cohort registry WorldWideWEB, including consecutive adult patients with intracranial aneurysms treated with the WEB. Patients were stratified into groups of ruptured and unruptured aneurysms. Propensity score matching was used to balance baseline characteristics between both groups. Retreatment rate was the primary outcome. Secondary outcomes included mRS, safety events (thromboembolic complications) and angiographic outcomes (periprocedurally and last follow-up). Results Among 1,220 patients, 342 (28.0%) presented with ruptured aneurysms. There was no significant difference in the rate of thromboembolic complications between groups (11.8% vs 5.9%, p = 0.056). At follow-up, adequate occlusion was lower (82.2% vs 93.3%, p < 0.002) and functional outcomes were worse (mRS ≥2 in 34.1% vs 21.9%, p = 0.012) among patients with ruptured aneurysms. Periprocedural adequate occlusion (53.3% vs 53.8%, p>0.9) and retreatment rates (11.8% vs 7.1%, p = 0.14) did not differ between groups after matching. Conclusion Ruptured aneurysms demonstrated expected inferior follow-up functional and angiographic outcomes when compared with unruptured aneurysms, but no difference in retreatment rate and procedural safety. These findings support WEB as a safe and effective treatment option for appropriately selected ruptured intracranial aneurysms in routine clinical practice.

Background Ischemic stroke is an important cause of morbidity and mortality in children, yet no clinical trials have evaluated mechanical thrombectomy (MT) in this population. Consequently, in contrast to adults, pediatric MT remains an off-label intervention. This meta-analysis aimed to assess its safety and efficacy and compare outcomes with medical management (MM). Methods MEDLINE, Scopus, and Web of Science were searched to identify original studies reporting outcomes of MT, with or without intravenous thrombolysis (IVT) in pediatric ischemic stroke. In studies that concurrently reported MT±IVT and MM±IVT within the same study, outcomes from the MM arms were also extracted for comparative analysis. Results Eighteen studies encompassing 612 pediatric patients were included. The pooled successful recanalization rate (thrombolysis in cerebral infarction (TICI) 2b–3) after mechanical thrombectomy was 88.9% (95% confidence interval (CI) 85.65 to 92.06), and 43.9% (95% CI, 38.67 to 49.09) achieved complete recanalization (TICI 3). Favorable functional outcomes (modified Rankin Scale (mRS) 0–2) occurred in 78.6% (95% CI, 69.58 to 87.61) of patients, with mortality and symptomatic intracranial hemorrhage (sICH) rates of 3.9% (95% CI, 1.88 to 5.92) and 1.3% (95% CI, 1.07 to 2.58), respectively. Shift analysis demonstrated a significant overall improvement in functional outcomes with MT±IVT compared with MM±IVT (common (OR), 0.43; 95% CI, 0.30 to 0.63; P<0.001). Conclusion Our findings suggest that MT has a favorable safety and efficacy profile, resulting in a more favorable mRS shift compared with MM in pediatric ischemic stroke. Further research is needed to identify the pediatric stroke patients who are likely to benefit from MT.