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.

Objective Aneurysm wall enhancement (AWE) is a potential biomarker of inflammation within the aneurysm wall that has been correlated with a higher risk of rupture. Aspirin (ASA) may decrease AWE due to its anti-inflammatory properties. We aimed to assess the effect of ASA on AWE in an animal model and a cohort of patients with unruptured intracranial aneurysms (UIAs). Methods Three rabbits with elastase-induced aneurysms were exposed to ASA for 8 weeks and three rabbits were used as controls. 3 T high-resolution magnetic resonance imaging (HR-MRI) was performed at 7 days and 8 weeks to evaluate changes in AWE through histological and immunohistological analyses. Additionally, we evaluated AWE in patients who underwent imaging with a 3 T HR-MRI protocol. ASA exposure was defined as daily intake of 81 mg for at least six months prior to HR-MRI. AWE was quantified using three-dimensional AWE maps and histograms. Results Among rabbits exposed to ASA, the mean AWE was lower at 8 weeks compared to the controls (2.11 vs 2.15, p = 0.13). Immunostaining of the aneurysm wall in rabbits that received ASA revealed a reduced expression of CD68 + or cyclooxygenase-2 + cells, compared to the controls. A total of 99 patients with 120 UIAs were included in the HR-MRI analysis of UIAs. UIAs exposed to ASA (22/120) had significantly lower median AWE than those that were not exposed (0.60 vs 0.72, p = 0.032). Conclusion ASA therapy is associated with an objective reduction in AWE, suggesting a potential role in lowering the risk of aneurysm rupture.

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.

Objective: To evaluate the safety and efficacy of recombinant human prourokinase (rhPro-UK) administered via intravenous (IV) and intra-arterial (IA) routes in acute ischemic stroke (AIS) patients compared with standard treatments. Methods: A comprehensive search was conducted in accordance with PRISMA guidelines across Scopus, Web of Science, and PubMed until 11 December 2024. Randomized controlled trials (RCTs) assessing rhPro-UK’s efficacy and safety were included. Outcomes included the modified Rankin Scale (mRS), the National Institutes of Health Stroke Scale (NIHSS), mortality, and adverse events (AEs). Data analysis used risk difference (RD) with 95% confidence intervals (CIs). Results: Six RCTs (n = 3993) met the inclusion criteria. IV rhPro-UK showed comparable efficacy to the comparator for the mRS 0–1 at 90 days (RD: 0.00, 95% CI: [−0.04, 0.04]) and the mRS 0–2 (RD: −0.01, 95% CI: [−0.03, 0.01], P = 0.23). IA rhPro-UK significantly improved the mRS 0–1 (RD: 0.13, 95% CI: [0.01, 0.26], P = 0.04). The NIHSS reduction was significant for IV rhPro-UK (MD: −0.83, 95% [CI: −1.36, −0.29]). IV rhPro-UK did not significantly reduce the risk of systemic bleeding (RD: −0.10, 95% CI: [−0.24, 0.03], P = 0.12), serious AEs (RD: −0.01, 95% CI: [−0.04, 0.02], P = 0.53), or mortality (RD: 0.01, 95% CI: −0.01, 0.02). IA rhPro-UK significantly increased hemorrhage with neurological deterioration (RD: 0.08, 95% CI: [0.01, 0.14], P = 0.02). Conclusions: IV rhPro-UK provides non-inferior efficacy to both alteplase and standard care with a better safety profile at 35 mg, while IA rhPro-UK enhances functional outcomes in middle cerebral artery occlusions, albeit with safety concerns. Further trials are needed to confirm long-term outcomes, optimal dosing, and broader applicability.

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: Variability in recanalization success during endovascular treatment for acute ischemic stroke (AIS) has led to increased interests in thrombus composition and associated cellular materials. While evidence suggests that bacteria may influence thrombus characteristics, limited data exist on microbiological profiles of thrombi in stroke patients. Objectives: Characterization of bacterial communities present in thrombi of AIS patients undergoing mechanical thrombectomy, providing insights into microbial contributions to stroke pathogenesis and treatment outcomes. Methods: Thrombi were collected from 20 AIS patients. After extracting metagenome, 16S rDNA sequencing was performed. Bioinformatic analysis included taxonomy and diversity assessments. The presence of bacterial DNA and viable bacteria in thrombi was validated using polymerase chain reaction (PCR) and bacterial culturing followed by matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) analysis, respectively. Results: 16S rDNA was amplified in 19/20 thrombi (95%). Analysis identified a diverse microbial community, with Corynebacterium spp. as the most prevalent genus, followed by Staphylococcus spp., Bifidobacterium spp., Methylobacterium spp., and Anaerococcus spp. Alpha diversity analyses (Shannon index: 4.0–6.0 and Simpson index: 0.8–1.0) revealed moderate to high microbial diversity across samples; beta diversity demonstrated distinct clustering, indicating inter-patient variability in microbial profiles. PCR confirmed the presence of DNA specific to dominant bacterial taxa identified through sequencing. Culturing showed the presence of Staphylococcus epidermidis and Enterococcus faecalis in some clots as identified through MALDI analysis. Conclusions: This study shows bacterial communities present in AIS patients’ thrombi, suggesting a potential link between microbial signatures and thrombus characteristics.

Background Carotid artery tortuosity (CAT) may complicate mechanical thrombectomy (MT), potentially causing delays or preventing recanalization. However, the relationship between CAT and MT outcomes remains largely unexplored. This systematic review aims to evaluate the existing evidence regarding the impact of CAT on MT outcomes. Methods Following PRISMA guidelines, a systematic literature search was conducted using MEDLINE, EMBASE, Web of Science, Cochrane, and Scopus databases. Studies providing data for MT outcomes based on CAT status were included. Outcomes of interest included successful recanalization, first-pass efficacy (FPE), procedure time, functional independence, and procedure-related complications. Results Our search identified nine studies with 2737 patients. Three studies employed DSA to assess tortuosity, whereas the remaining six studies preferred CTA. In seven studies, CAT was associated with prolonged procedure times. In five studies, successful recanalization rates were significantly lower in CAT patients as compared to patients with non-tortuous arteries. Two studies showed that CAT could alter FPE or successful recanalization rates of first-line MT techniques. No study found statistically significant relationships between CAT and functional independence. Three studies examined the association between CAT and safety outcomes, and only one study found increased intracranial hemorrhage rates in patients with CAT. All nine studies employed different CAT criteria. Conclusions Despite the vast MT literature, the number of studies reporting CAT status remains low. CAT may affect procedure time and technical outcomes of MT. Therefore, employing a uniform CAT definition and reporting CAT more frequently can provide insights into management of patients with acute large vessel occlusions.