Citations

Cerebrospinal fluid venous fistulas (CSFVF) can lead to spontaneous intracranial hypotension, causing debilitating symptoms in patients. The transvenous embolization technique has been developed to occlude leakage sites via an endovascular approach. However, the spinal venous anatomy remains relatively unfamiliar to many neurointerventionalists. This technical video presents a swine model designed to train physicians in navigating the spinal venous system, performing embolization injections, observing their spread, and testing new embolization systems for treating CSFVF. Although there are slight anatomical differences, the spinal venous system in swine closely resembles that of humans, including its navigability and employing liquid embolic agents. We successfully embolized multilevel spinal vasculature that can potentially drain into a fistula formation, without any complications.

Background and purpose New Zealand White Rabbits are a useful preclinical model for neurovascular research. Inducing right common carotid artery aneurysms in New Zealand White Rabbits gives researchers the ability to test neurovascular devices in vivo. This study takes advantage of archived angiograms to obtain vascular measurements of interest for future research in rabbit models. Methods Rabbit angiograms from endovascular studies conducted in-house between 2005 and 2024 were analyzed using ImageJ at points of interest along the thoracic and abdominal aorta. Using scale references, the diameters of various New Zealand White Rabbit (2.5–3.5 kg) arteries were measured for aneurysm models and controls. Anatomic vascular variations were categorized and recorded. Results Measurable artery diameters at 39 points of interest were recorded for 170 female New Zealand White Rabbits. Type 1 vascular anatomy was the most common rabbit aortic arch, characterizing 85% of identifiable rabbit anatomies in this study. Conclusion By making these measurements available, this study simplifies future neurovascular studies, allowing for vasculature to be selected by size depending on the application. Additionally, the study offers insight into the relationship between elastase-induced aneurysms and surrounding vasculature size and draws size comparisons between some key arteries of interest.

Background The first-pass effect (FPE) refers to the complete or near-complete revascularization with a single pass of mechanical thrombectomy devices. While previous claims suggest a link between larger catheters and the effectiveness of contact aspiration (CA) thrombectomy, no extensive research has confirmed if larger distal inner diameter (ID) catheters achieve higher FPE rates. Methods We searched PubMed, Scopus, and Web of Science to assess the impact of aspiration catheter distal ID size on FPE. The primary outcome was FPE rate, defined as thrombolysis in cerebral ischemia (TICI) grades 2c-3 at first pass, and the secondary outcome was modified FPE (TICI 2b-3 in a single pass). Aspiration catheters were categorized based on distal ID: 0.060–0.069 (medium bore), 0.070–0.074 (large bore), and greater than 0.074 inches (super-large bore). Rates of FPE were pooled using random effect models and compared using a Chi-square test. Results Our study included 34 articles with 4831 patients. FPE rates were 27.7% (95% CI, 15.1–45.3) for medium bore, 46.6% (95% CI, 33.7–59.9) for large, and 58.3% (95% CI, 44.8–70.7) for super-large catheters. The FPE rate was significantly higher for super-large bore catheters compared with other groups (χ² = 7.26, p = 0.03). A similar trend was observed for modified FPE rates, which were 51.1% (95% CI, 45.3–56.8) for medium bore, 60.0% (95% CI, 52.8–66.8) for large bore, and 80% (95% CI, 56.3–94.2) for super-large bore catheters (χ² = 8.14, p = 0.03). Conclusion Our analysis indicates that larger CA catheters are correlated with higher FPE rates.

Background Accurate and timely prehospital detection of large vessel occlusion (LVO) is critical for optimizing patient triage and initiating appropriate reperfusion therapies. Recent advances in portable stroke detection technologies, such as electroencephalography (EEG) and transcranial Doppler (TCD) ultrasound, offer potential solutions but their diagnostic performance remains unclear. Methods We searched PubMed, Scopus, Embase, and Web of Science, following the PRISMA guidelines. Studies were included if they assessed the diagnostic performance of non-invasive prehospital LVO detection tools compared to CT or MR angiography. Risk of bias was assessed using the QUADAS-2 tool. Results A total of 13 studies were included, examining various portable detection tools including EEG or neurophysiological monitoring, ultrasound-based techniques including TCD or TCCD, portable Openwater optical blood flow monitor and cranial accelerometry. The pooled diagnostic odds ratio (DOR) was 52.7 (95% CI: 28.3–97.8), indicating strong diagnostic performance, with significant heterogeneity among studies (I 2 = 67.3%, P < 0.001). Subgroup analysis revealed that TCD-based methods had the highest DOR (120.4, 95% CI: 76.9–188.7), followed by other tools (26.8, 95% CI: 13.7–52.6), and EEG (18.2, 95% CI: 9.1–36.3). The pooled sensitivity was 87.4% (95% CI: 82.5–91.0) and specificity was 89.39% (95% CI: 83.0–93.5) across all methods. TCD-based methods showed the highest specificity (95.0%, 95% CI: 91.8–97.0). Conclusion Non-invasive prehospital LVO detection tools show promising diagnostic performance, particularly TCD-based methods. Future studies should focus on validating these tools in larger, diverse populations to enhance prehospital stroke triage and improve patient outcomes.

Background Mechanical thrombectomy for ischemic stroke has traditionally been performed via transfemoral access (TFA). However, newer literature on the subject suggests that transradial access (TRA) may be equally efficacious. Methods Online databases (including PubMed, Google Scholar, Embase, and Cochrane) were queried from inception until May 2024. Abstracts and full texts were screened according to Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. Risk of bias assessment was performed using standardized screening tools. All dichotomous outcomes were reported as odds ratio (OR) with 95% confidence interval (CI). RevMan was used to perform the statistical analysis. Results Thirteen observational studies and one randomized clinical trial (RCT) were included in this meta-analysis. The total sample size was 4973, 4074 patients (81.2%) were in the TFA group, and 899 (18.8%) were in the TRA group. No significant differences were observed between the two groups in terms of successful recanalization (OR = 0.92; 95% CI 0.66–1.27; p = 0.60), first-pass recanalization (OR = 0.84; 95% CI 0.69–1.01, p = 0.06), access to reperfusion time (mean difference −2.99 min; 95% CI −8.33 to 2.44, p = 0.27), and favorable functional outcome. Mortality and rates of intracranial hemorrhage were comparable between the two groups, but access site complications were significantly lower in the TRA group (OR = 0.57; 95% CI 0.37–0.88; p = 0.01). Conclusion TRA for thrombectomy in large vessel ischemic strokes is comparable to TFA in terms of efficacy and has a lower incidence of access site complications. RCT data comparison of the two techniques is limited, underscoring the importance of conducting trials.

We have developed a cost-effective method to study the fate of stents, particularly flow diverter stents placed in the abdominal aorta, in a rat model. This technique utilizes (caudal) tail artery access,1–5 thereby avoiding the need for surgical exposure of the femoral or carotid arteries and reducing procedural invasiveness,6 7 aligning with the principles of refinement and reduction in animal research.7 This approach may be particularly beneficial for studies requiring multiple or iterative vascular access. The use of ultrasound guidance further reduces costs and infrastructure requirements by eliminating the need for specialized angiography suites.8 This makes this technique accessible to a broader range of research settings, promoting wider adoption and collaboration in the field of endovascular research. A detailed demonstration of this method is provided in the accompanying educational video (video 1). Video 1 -Technical video describing the tail artery access and flow diverter deployment using ultrasound guidance.

Brain arteriovenous malformations (bAVMs) are a notable cause of intracranial hemorrhage, strongly associated with severe morbidity and mortality. Contemporary treatment options include surgery, stereotactic radiosurgery, and endovascular embolization, each of which has limitations. Hence, development of pharmacological interventions is urgently needed. The recent discovery of the presence of activating Kirsten rat sarcoma ( KRAS ) viral oncogene homologue mutations in most sporadic bAVMs has opened the door for a more comprehensive understanding of the pathogenesis of bAVMs and has pointed to entirely novel possible therapeutic targets. Herein, we review the status quo of genetics, animal models, and therapeutic approaches in bAVMs.

Background The hypoperfusion intensity ratio (HIR) has emerged as a vital measure of tissue-level collateral blood flow, helping to identify patients who are likely to benefit from mechanical thrombectomy (MT). We aimed to assess the HIR’s predictive accuracy for clinical outcomes following MT in patients with acute ischemic stroke. Methods PubMed, Embase, and Scopus were searched to identify studies comparing good versus poor HIR groups based on studies’ reported cut-offs. We pooled binary outcomes to calculate odds ratios (OR) and continuous outcomes to calculate mean differences (MD) with 95% confidence intervals (95% CI) using random-effects models. PROSPERO registration code: CRD42024609185. Results 14 studies with 2987 patients, 1553 with good HIR and 1434 with poor HIR, were included in this meta-analysis. Patients with poor HIR exhibited a significantly higher baseline infarct volume compared with those with good HIR (MD 30.6 mL, 95% CI 20.8 mL to 40.3 mL, P<0.01), though baseline National Institutes of Health Stroke Scale (NIHSS) (P=0.12) and Alberta Stroke Program Early CT Score (ASPECTS) (P=0.35) were comparable between groups. The rates of infarct growth (MD 22.4 mL, 95% CI 6.7 mL to 38.0 mL, P<0.01) and 3-month mortality (OR 2.18, 95% CI 1.04 to 4.58, P=0.04) were higher among the poor HIR group and good functional recovery (modified Rankin Scale 0–2 at 3 months) was lower (OR 0.58, 95% CI 0.42 to 0.80, P<0.01). The rates of symptomatic intracranial hemorrhage (P=0.37) and successful reperfusion (P=0.47) were comparable among groups. Conclusion This meta-analysis highlights the significant negative impact of poor HIR on patient outcomes. These findings emphasize the need for personalized treatment strategies for patients with poor HIR.