Radiopaque FeMnN-Mo composite drawn filled tubing wires for braided absorbable neurovascular devices.

Flow diverter devices are small stents used to divert blood flow away from aneurysms in the brain, stagnating flow and inducing intra-aneurysmal thrombosis which in time will prevent aneurysm rupture. Current devices are formed from thin (∼25 µm) wires which will remain in place long after the aneurysm has been mitigated. As their continued presence could lead to secondary complications, an absorbable flow diverter which dissolves into the body after aneurysm occlusion is desirable. The absorbable metals investigated to date struggle to achieve the necessary combination of strength, elasticity, corrosion rate, fragmentation resistance, radiopacity, and biocompatibility. This work proposes and investigates a new composite wire concept combining absorbable iron alloy (FeMnN) shells with one or more pure molybdenum (Mo) cores. Various wire configurations are produced and drawn to 25-250 µm wires. Tensile testing revealed high and tunable mechanical properties on par with existing flow diverter materials. In vitro degradation testing of 100 µm wire in DMEM to 7 days indicated progressive corrosion and cracking of the FeMnN shell but not of the Mo, confirming the cathodic protection of the Mo by the FeMnN and thus mitigation of premature fragmentation risk. In vivo implantation and subsequent µCT of the same wires in mouse aortas to 6 months showed meaningful corrosion had begun in the FeMnN shell but not yet in the Mo filament cores. In total, these results indicate that these composites may offer an ideal combination of properties for absorbable flow diverters.

Impact of frailty on post-operative outcomes following subarachnoid hemorrhage: A systematic review and meta-analysis.

BACKGROUND: Subarachnoid hemorrhage (SAH) is associated with high rates of mortality and morbidity, particularly among elderly patients. The presence of frailty may impact survival rates in patients with SAH. In this study, we aim to investigate the impact of frailty on the clinical outcomes in SAH patients. METHODS: We conducted a systematic review and meta-analysis following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Relevant papers through December 2023 were retrieved from PubMed, Scopus, Web of science, and Embase. RESULTS: A total of 5 studies met inclusion/exclusion criteria with an aggregate 39,221 non-frail patients (mean age 52.4 ± 5.2 yr; 62.1 % Female), and 79,416 frail patients (mean age 61.1 ± 5.4 yr; 69.0 % Female). Frailty was significantly associated with higher mortality ratio (Odds ratio (OR)= 2.09; CI [1.04: 4.20], p= 0.04), and increased length of hospital stay (OR= 1.40; CI [1.07: 1.83], p= 0.015). Additionally, frailty was associated with higher odds of external ventricular drain insertion, the need of tracheostomy/endoscopic gastrostomy, increased risk of deep vein thrombosis, and postoperative neurological complications. CONCLUSION: Frailty is associated with worse clinical outcomes and higher mortality rates in SAH patients. Our findings highlight that frailty, when considered alongside other established prognostic factors, serves as crucial predictor for peri-operative complications and overall hospital course in SAH patients.

Triple Aspiration Versus Conventional Aspiration Techniques: A Randomized In-Vitro Evaluation.

BACKGROUND AND PURPOSE: A single aspiration maneuver using a large volume syringe is a common and effective technique for aspiration thrombectomy. Multiple aspiration cycles using large aspiration syringes has been proposed as a means to improve efficacy over single aspiration. In this study, we sought to investigate the efficacy of a "triple aspiration technique" where a large volume syringe is cycled three times prior to catheter retraction during aspiration thrombectomy. MATERIALS AND METHODS: A 3D-printed adult vasculature was used as a benchtop thrombectomy platform. Fibrin-rich and red blood cell-rich clots were prepared in centrifuge tubes using human plasma, red blood cells, and calcium chloride. Next, clots were placed in the carotid terminus of the model, and the performances of three different aspiration techniques-triple syringe, single syringe, and continuous pump aspiration-were compared in a randomized manner (1:1:1). Outcomes of interest included first-pass efficacy (FPE), complete clot removal (final mTICI 2c/3), the number of thrombectomy attempts to achieve mTICI 2c/3, vacuum pressure, and distal embolization. The distal emboli were detected using a 70-micron cell strainer placed at the outflow of the model and quantified using an image processing algorithm. The vacuum pressures were measured using a pressure transducer (Honeywell, NC, USA). RESULTS: A total of 102 replicates were performed, 34 for each technique. The triple aspiration technique provided a significantly higher rate of FPE than the syringe and pump aspiration techniques (67.6% vs. 41.1%, p= 0.02). Additionally, the triple aspiration technique achieved complete clot removal with a significantly lower number of thrombectomy attempts compared to single syringe aspiration (1.2 ± 0.5 vs. 1.8 ± 0.8, p=0.005). The triple aspiration technique generated significantly higher vacuum pressure than both the single syringe and vacuum pump aspiration (28.3 ± 0.2 vs. 27.2 ± 0.3 (p= 0.002) and 26.2 ± 0.4 (p=0.001), respectively). The differences in complete clot removal and distal embolization parameters were not statistically significantly different across the groups. CONCLUSIONS: Our findings suggest that the triple aspiration technique can improve FPE rates and vacuum pressure in aspiration thrombectomy. Further studies are needed to examine the safety and efficacy of triple aspiration in the clinical setting. ABBREVIATIONS: AcommA = anterior communicating artery; FPE = first pass efficacy; ICA = internal carotid artery; MCA = middle cerebral artery; MT = mechanical thrombectomy; mTICI = modified thrombolysis in cerebral infarction scale; PcommA = posterior communicating artery.

In vitro evaluation of flow diverter performance using a human fibrinogen-based flow model.

OBJECTIVE: Fibrin deposition represents a key step in aneurysm occlusion, promoting endothelization of implants and connective tissue organization as part of the aneurysm-healing mechanism. In this study, the authors introduce a novel in vitro testing platform for flow diverters based on human fibrinogen. METHODS: A flow diverter was deployed in 4 different glass models. The glass models had the same internal parent artery (4 mm) and aneurysm (8 mm) diameters with varying parent artery angulations (paraophthalmic, sidewall, bifurcation, and slightly curved models). The neck size and area were 4 mm and 25 mm2, respectively. Human fibrinogen (330 mg/dl) was circulated within the glass models at varying flow rates (0, 3, 4, and 5 ml/sec) with or without heparin, calcium chloride, and thrombin for as long as 6 hours or until complete fibrin coverage of the flow diverter's neck was achieved. Aneurysm neck coverage was defined as macroscopic fibrin deposition occluding the flow diverters' pores. Flow characteristics after flow diverter deployment were assessed with computational fluid dynamics analysis. The effects of flow rates, heparin, calcium chloride, and thrombin on fibrin deposition rates were tested using 1-way ANOVA and the Tukey test. RESULTS: A total of 84 replicates were performed. Human fibrin did not accumulate on the flow diverter stents under static conditions. The fibrin deposition rate on the aneurysm neck was significantly greater with the 5 ml/sec flow rate as compared to 3 ml/sec for all models. The paraophthalmic model had the highest inflow velocity of 48.7 cm/sec. The bifurcation model had the highest maximum shear stress (SS) and maximum normalized shear stress values at the device cells at 843.3 dyne/cm2 and 35.1 SS/SSinflow, respectively. The fibrin deposition rates of the paraophthalmic and bifurcation models were significantly higher than those of sidewall and slightly curved models for all additive or flow rate comparisons (p = 0.001 for all comparisons). The incorporation of thrombin significantly increased the fibrin deposition rates across all models (p = 0.001 for all models). CONCLUSIONS: Rates of fibrin deposition varied widely across different configurations and additive conditions in this novel in vitro model system. Fibrin accumulation started at the aneurysm inflow zone where flow velocity and shear stress were the highest. The primary factors influencing fibrin deposition included flow velocities, shear stress, and the addition of thrombin at a physiological concentration. Further research is needed to test the clinical utility of fibrinogen-based models for patient-specific aneurysms.

Reporting Compliance and Factors Influencing Timeliness of Stroke-Related Trial Results on ClinicalTrials.gov.

Since 2007, research groups are mandated by the Food and Drug Administration Amendments Act (FDAAA) to report clinical trial findings to ClinicalTrials.gov within 12 months of trial completion. This observational study aims to analyze compliance data of stroke-related randomized controlled trials subject to these mandates. Using a previously published algorithm, we identified clinical trials likely to be required to adhere to FDAAA mandates (highly likely applicable clinical trials, or HLACTs) from January 2008 to February 2023. We assessed the proportion of studies that reported results within 12 months of trial completion, as well as those that reported at any point within 5 years. Additionally, we utilized Kaplan-Meier and regression analysis to explore factors associated with on-time reporting. Among 357 stroke-related HLACTs on ClinicalTrials.gov that were terminated or completed between January 1, 2008, and February 1, 2023, 59 (16.5%) reported results within 12 months, while 320 (89.6%) reported results within 5 years. Median reporting times for industry funded, other government or academic institution funded, and National Institute of Health (NIH) funded studies were 18.5 months, 22 months, and 22.5 months, respectively. Open-label studies were less likely to report results by 12 months compared to double-blinded studies (p = 0.002). Biological trials exhibited a lower probability of reporting within 5 years compared to device and/or drug trials (p = 0.007). Clinical trial registries and FDAAA mandates aim to promote accountability and transparency in health sciences research. However, regardless of their funding source, only a minority of stroke-related randomized controlled trials comply with FDAAA's 12-month result reporting mandate.

Creating elastase aneurysms in rabbits: a video primer.

The New Zealand rabbit elastase-induced arterial aneurysm of the right common carotid artery remains a widely used model for assessing the effectiveness and safety of new neuroendovascular devices.1 This model offers a simple and reliable platform for pre-clinical in vivo investigations, crucial for comprehending the biological processes underlying aneurysm healing after endovascular treatment.2 Notably, the induced aneurysm exhibits morphological, hemodynamic, and histological characteristics similar to human intracranial aneurysms. The creation of the aneurysm is performed using open and endovascular techniques. Each step of the procedure requires a meticulous and controlled gesture to ensure reproducibility of the aneurysm and minimize animal misuse. In video 1 we present a step-by-step procedural guide for aneurysm creation and follow-up. We hope this resource will help in promoting this model and provide useful guidance for researchers in the field.neurintsurg;jnis-2024-021912v1/V1F1V1Video 1Surgical procedure of creating elastase-induced aneurysms in rabbits.

Comparative meta-analysis of endovascular strategies for intracranial dissecting aneurysms: Flow diverters versus stents with or without coiling.

BACKGROUND: Intracranial dissecting aneurysms present a challenging subset linked to considerable morbidity and mortality, necessitating effective therapeutic strategies to prevent complications. Traditional treatments face technical limitations, while emerging endovascular modalities like stent-assisted coiling, multiple stenting, and flow-diverting devices (FDDs) offer promise in reducing periprocedural risks and enhancing patient outcomes. The aim of this study is to compare the safety and efficacy outcomes of endovascular treatment for intracranial dissecting aneurysms using FDDs versus stents (with or without coiling). METHODS: A systematic review and meta-analysis were conducted following established guidelines. The search included PubMed, Scopus, Web of Science, and Embase databases up to July 30, 2023. Eligible studies reporting outcomes of interest in both FDD and stent-treated groups were included, and the data was extracted and analyzed using STATA software. RESULTS: Six studies were analyzed, involving 131 patients in the FDD group and 199 patients in the stent group. The pooled rates for favorable functional outcomes (86.8% vs. 86%), mortality (3.9% vs. 6%), adequate occlusion (79.7% vs. 86.3%), aneurysm recurrence (1.3% vs. 13.3%), in-stent stenosis/thrombosis (7% vs. 6.9%), ischemic events/infarctions (6.7% vs. 7.8%), retreatment (7% vs. 8.6%), and technical success (100% vs. 98.7%) were comparable in individuals treated with FDDs and stents (p > 0.05 in all cases). Additionally, complete occlusion rates were not significantly different between FDD (62.7%) and stent-treated patients (75.2%) (p = 0.06). However, after excluding one study in a leave-one-out analysis of the random effects meta-analysis, a significant difference in the pooled rates of this outcome was observed between the FDD (59.2%) and stent (75.2%) groups (p = 0.034). CONCLUSION: FDDs present a promising approach for the treatment of intracranial dissecting aneurysms, yielding outcomes that are roughly comparable to stent-based methods. However, the absence of randomized trials and data limitations highlight the need for further research to enhance treatment strategies.

Common design and data elements on rectal artery embolization for treatment of symptomatic internal hemorrhoidal disease: an interactive systematic review of clinical trials.

BACKGROUND: Internal hemorrhoids (IH) is a common medical condition that can result in morbidity secondary to bleeding and discomfort. Treatment for IH has traditionally consisted of dietary and conservative medical management, focal treatments including banding and sclerotherapy or hemorrhoidectomy. Recently, rectal artery embolization (RAE) has been studied as a potential treatment for bleeding predominant IH. We performed a common design and data element analysis of studies that report on RAE. MATERIALS AND METHODS: We conducted a qualitative systematic literature review for rectal artery embolization (RAE) for symptomatic hemorrhoidal disease. The screening process involved five online databases (PubMed, Embase, Google Scholar, DOAJ, and Scopus). Additionally, ClinicalTrials.gov was examined for active, unpublished completed studies. The initial search yielded 2000 studies, with 15 studies meeting the inclusion criteria after screening and assessment. The included studies comprised one RCT, one case series, one pilot study and 12 cohort studies. RESULTS: The population analysis revealed a male predominance across all studies, with varying cohort sizes. The baseline Goligher hemorrhoid grade was utilized in 80% of studies. The majority (73.3%) employed a transfemoral approach, and coils were the primary embolic material in 60% of studies, 26.6% were combination of coils and particles, and 6.6% were particles only. Patient selection criteria highlighted RAE's applicability for high surgical risk patients and those with anemia, chronic hematochezia, or treatment-refractory cases. Exclusion criteria emphasized factors such as previous surgeries, colorectal cancer, rectal prolapse, acute hemorrhoidal complications, and contrast allergy. Study designs varied, with cohort studies being the most common (12/15; 80%). Procedural details included the use of metallic coils and detachable micro-coils, with a high technical success rate reported in most studies ranging from 72 to 100%. The follow-up ranged from 1 to 18 months. The majority of studies reported no major immediate or post-procedural complications. CONCLUSION: While all studies focused on RAE as a treatment for IH, there was a great degree of heterogeneity among included studies, particularly regarding inclusion criteria, exclusion criteria, outcomes measures and timeframe. Future literature should attempt to standardize these design elements to help facilitate secondary analyses and increase understanding of RAE as a treatment option.

Outcomes of mechanical thrombectomy in octogenarians and nonagenarians patients with Acute Ischemic Stroke: A Systematic Review and Network Meta-Analysis.

PURPOSE: Acute ischemic stroke (AIS) imposes a major healthcare burden, with the elderly population often underrepresented in clinical trials. This systematic review and network meta-analysis aims to evaluate the safety and efficacy of mechanical thrombectomy (MT) among octogenarians and nonagenarians with AIS due to large vessel occlusion (LVO). METHODS: A systematic search was conducted using PubMed, Web of Science, and Scopus databases. Outcomes of interest were modified Rankin Scale (mRS) score of 0-2, thrombolysis in cerebral infarction (TICI) score of 2b-3, 90-day mortality, and symptomatic intracerebral hemorrhage (sICH). The study followed Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines. RESULTS: The analysis included 47 studies. Significantly lower rates of mRS score 0-2 were observed in nonagenarians (17.4 %) and octogenarians (21.3 %) compared to younger (40.2 %) patients (Odds Ratio (OR) = 3.30, 95 % Confidence Interval (CI):2.35-4.65 and OR = 2.47, 95 % CI: 2.07-2.94). 90-day mortality was significantly higher in nonagenarians (38.9 %) compared to octogenarians (25.4 %) and younger (14.0 %) patients (OR = 0.58, 95 % CI: 0.41-0.83 and OR = 0.31, 95 % CI: 0.21-0.44), and in octogenarians compared to younger patients (OR = 0.52, 95 % CI: 0.41-0.66). No significant differences were observed in TICI 2b-3 and sICH rates across groups. CONCLUSIONS: Our findings indicate that MT is a viable treatment option for AIS due to LVO among octogenarians and nonagenarians, albeit with nuanced differences. Specifically, octogenarians had lower 90-day mortality rates compared to nonagenarians. These insights support the need for individualized treatment plans for elderly patients with AIS due to LVO and highlight the importance of including this demographic in future clinical trials.

How the elastase-induced rabbit aneurysm heals following flow diverter treatment: a histopathological study.

OBJECTIVE: Fibrin deposition is integral to thrombus formation and wound healing. The role of fibrin deposition and subsequent metabolism following flow diversion for aneurysm treatment remains poorly characterized. This study aimed to evaluate the role of fibrin in early thrombus organization after flow diverter treatment. METHODS: Thirty-five elastase-induced aneurysms were induced in New Zealand white rabbits and subjected to endoluminal flow diversion treatment. The device-bearing arteries were harvested at 1, 3, and 6 months postimplantation and processed for histopathological examination, including a modified picro-Mallory stain (Carstairs method) to visualize fibrin and platelets, immunohistochemical targeting of smooth muscle actin (SMA), and H&E staining for conventional morphological evaluation. Quantitative analysis of tissue components was carried out using the Orbit Image Analysis software. The samples were also assessed qualitatively to investigate the morphology and location of fibrin and other thrombus components within the intra-aneurysmal thrombi. Statistical analyses were conducted using R software version 4.3.1. RESULTS: Fibrin constituted 27.9% of the thrombus tissue within the aneurysm sac for aneurysms harvested at 1 month, and this rate was significantly lower in the 3-month group (10.2%, p = 0.018). The proportion of blood cells within the sac was also notably higher in the 1-month group compared with other time points. The primary tissue filling the dome at 1 month (14/15, 93%) was an unorganized thrombus primarily composed of fibrin, platelets, and red blood cells. Conversely, aneurysms harvested at 1 month had the lowest collagen level (25.6%). However, collagen became the dominant tissue component within the aneurysm sac, accounting for 71.8% of tissue in the 3-month group (p = 0.007). There were no differences observed among the examined components between the 3-month and 6-month groups. On qualitative analysis, collagen-producing SMA-positive myofibroblasts were located near or in between fibrin molecules. Healed aneurysms exhibited myofibroblasts, collagen, and a well-organized fibrin network on the aneurysm neck. In contrast, unhealed aneurysms displayed a poorly organized fibrin network with scattered myofibroblasts at the neck area. CONCLUSIONS: These findings indicate that fibrin plays a foundational role in the gradual occlusion of aneurysms after flow diverter treatment. Endovascular approaches that enhance fibrin accumulation could potentially improve aneurysm occlusion rates. Further research is needed to establish the precise role of fibrin in aneurysm occlusion.

eCLIPs bifurcation remodeling system for treatment of wide-neck bifurcation aneurysms: A systematic review and meta-analysis of safety and efficacy.

BACKGROUND: Wide neck bifurcation aneurysms (WNBAs) are a subtype of aneurysms that are especially complex to treat. We aim to conduct a systematic review and meta-analysis to synthesize the available literature on the safety and efficacy of employing endovascular clip system (eCLIPs) in the treatment of WNBAs. METHODS: We report this study in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 guidelines. PubMed, Embase, Web of Science, and Scopus were queried for this review. Screening and extraction were performed by at least two authors to ensure accuracy and completeness, and a senior author arbitrated any discrepancies. All data were analyzed using R software version 4.3.0. and random-effects model. RESULTS: Four studies were finally included, of which three were prospective and one was retrospective. Successful adjunctive coiling occurred in 91.38% (95% CI = 70.71-97.9) of cases and overall technical success was achieved in 88.61% (95 CI = 75.54-95.15) of cases. The pooled complete occlusion (Raymond-Roy Class I) was 50.65% (95% CI = 39.63-61.60) and adequate occlusion (Raymond-Roy Class I/II) was 84.42% (95% CI = 74.53-90.93). Thrombo-embolic complication had a pooled rate of 1.22% (95% CI = 0.17-8.15), retreatment rate was 6.10% (95% CI = 2.56-13.83), and mortality reported in 3.66% (95% CI = 1.18-10.74) of patients. CONCLUSION: The use of eCLIPs may be a safe and efficacious treatment for WNBAs. Future randomized controlled trials are needed for further validation of the findings.

The impact of pre-stroke metformin use on clinical outcomes after acute ischemic stroke: A systematic review and meta-analysis.

OBJECTIVES: Stroke is a leading cause of mortality and disability globally, with limited treatment options available for acute ischemic stroke (AIS) patients. Type 2 diabetes mellitus (T2DM) is not only widespread but also a known risk factor for stroke. Our meta-analysis aims to assess the influence of pre-stroke metformin use on the clinical outcomes in AIS patients with T2DM. MATERIALS AND METHODS: We conducted this study following PRISMA guidelines, searching the following databases: Medline, Embase, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials up to February 29, 2024. All studies providing separate data on AIS patients using metformin were included, and statistical analysis was conducted using R software to pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI). RESULTS: Out of 1051 studies, 7 met the inclusion criteria for our meta-analysis with a total of 11589 diabetic patients, including 5445 patients taking metformin and 6144 diabetic patients in the non-metformin group. Compared to the non-metformin group, the metformin group had a significantly higher rate of mRS 0-2 score at discharge (OR 1.56; 95% CI 1.25:1.95; p=< 0.01) and a lower rate of 90-day mortality (OR 0.51; 95% CI 0.42:0.61; p=< 0.01), with no significant difference in sICH (OR 0.88; 95% CI 0.47:1.64; p= 0.68) between the two groups. CONCLUSIONS: Our meta-analysis demonstrated that pre-stroke metformin use is associated with higher functional independence and lower mortality in AIS patients with T2DM.

Outcomes of mechanical thrombectomy in patients with acute ischemic stroke and thrombocytopenia: systematic review and meta-analysis.

BACKGROUND: Mechanical Thrombectomy (MT) has improved outcomes in acute ischemic stroke (AIS) due to Large Vessel Obstruction (LVO). However, there is limited data on the safety and outcomes of MT in AIS patients with thrombocytopenia. This study aims to assess the efficacy and safety of MT in this population. METHODS: Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus. Studies meeting inclusion criteria underwent rigorous risk of bias assessment using the ROBINS-I tool. We compared outcomes between patients with and without thrombocytopenia undergoing MT. Using the R software version 4.3.1, meta-analyses were conducted employing random-effect models. RESULTS: This meta-analysis encompassed data from 5 studies. Thrombocytopenic AIS patients who underwent MT (n = 974) exhibited lower rates of functional independence (OR 0.83, 95% CI 0.71-0.98; p = 0.030) compared to patients with normal platelet counts (n = 2036). In addition, the thrombocytopenic group experienced higher mortality as compared to the group with normal platelet counts (OR 1.76, 95% CI 1.26-2.45; p < 0.001). Rates of sICH were found to be similar between groups (OR 1.20, 95% CI 0.74-1.93; p = 0.456), as were rates of successful recanalization (OR 0.94, 95% CI 0.47-1.87; p = 0.863). Lastly, no significant differences were observed in procedure times between thrombocytopenic and non-thrombocytopenic groups. CONCLUSION: As compared to patients without thrombocytopenia, thrombocytopenic AIS patients undergoing MT displayed lower functional independence and higher mortality rates, with no significant differences in sICH or successful recanalization.

Endovascular Thrombectomy for Carotid Pseudo-occlusion in the Setting of Acute Ischemic Stroke: A Comparative Systematic Review and Meta-Analysis.

BACKGROUND: The effective treatment for acute ischemic stroke (AIS) patients with cervical internal carotid pseudo-occlusion (cICA-PO) requires comprehensive research on the safety and outcomes of endovascular thrombectomy (EVT). However, there is limited data available, highlighting the need for further research to ensure better treatment strategies and improve the quality of care for these patients. PURPOSE: This study aims to assess the management and outcomes in this population group compared to patients with true carotid occlusion. DATA SOURCES: Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus from data base inception to November 2023. STUDY SELECTION: The size of the included studies ranged from 16 patients to 146 patients. Through the 4 full-text articles, a total of 259 patients were collected. We compared outcomes between patients with cICA-PO compared to patients with true carotid occlusions undergoing EVT due to AIS. We excluded studies with patients with carotid pseudo-occlusion without stroke, review articles, duplicate studies, overlapped data that included the same patients presented in another included study, case reports, case series with fewer than 5 patients, and meeting abstracts that did not contain the outcomes of interest. We did not pose any limitations regarding sample size or patients' characteristics. DATA ANALYSIS: We utilized the R statistical software (V.4.3.1; R package meta, R Foundation for Statistical Computing, Vienna, Austria) to conduct the analysis of all the data obtained. We calculated the odds ratio (OR) for binary variables, and the corresponding 95% confidence interval (CI). To synthesize the data, random-effect models, as well as forest plots were generated to visually represent the synthesis of the data. Additionally, we assessed heterogeneity using Cochran's Q and I2 tests. A P-value less than 0.05 for the Q statistic or I2 more than 50% suggests significant heterogeneity. Based on a small number of studies (less than 10), the assessment of publication bias could not be reliably performed. DATA SYNTHESIS: This meta-analysis encompassed data from 4 studies. Patients with cICA-PO and AIS who underwent EVT (n = 135) exhibited lower rates of functional independence (OR 0.35, 95% CI 0.20-0.61, p= <0.001) compared to patients with true occlusions (n = 103), as well as successful recanalization rates (OR 0.39, 95% CI 0.20-0.74, p=0.004). In addition, the cICA-PO group experienced higher mortality and sICH compared to the group with true carotid occlusions (OR 2.62, 95% CI 0.21-7.24, and OR 2.23, 95% CI 1.00-4.95, p= 0.049, respectively). LIMITATIONS: Individual patient data was not available. Studies were a retrospective design and some of the studies had small sample sizes. The included studies in our metaanalysis did not exclude patients with tandem occlusions which might influence the results of the comparison. CONCLUSIONS: As compared to patients with true carotid occlusion, the cICA-PO group with AIS undergoing EVT presented poor outcomes with lower functional independence and successful recanalization, as well as higher sICH and mortality rates.

High thrombin-activatable fibrinolysis inhibitor expression in thrombi from stroke patients in elevated estrogen states.

BACKGROUND: The risk of acute ischemic stroke (AIS) associated with high estrogen states, including pregnant patients and those using oral contraceptives, has been well documented. We described the histological composition of thrombi collected in these cases. METHODS: From a prospective tissue registry (STRIP registry) of thrombi retrieved during mechanical thrombectomy for AIS, we identified 5 patients with high estrogen states: 1 post-partum patient, 1 undergoing hormone replacement therapy and 3 consuming oral contraceptive pills. Five male control patients were randomly chosen matched by age. Immunohistochemistry for CD42b (platelets), von Willebrand factor (vWF), thrombin-activatable fibrinolysis inhibitor (TAFI), fibrinogen and plasminogen activator inhibitor-1 (PAI-1) was performed. Expression was quantified using Orbit Image Software. Student's t-test was performed as appropriate. RESULTS: Mean TAFI content for the high estrogen state group was higher than controls (25.6 ± 11.9% versus 9.3 ± 9.0%, p = 0.043*). Mean platelet content for the high estrogen state group was lower than controls (41.7 ± 10.6% versus 61.8 ± 12.9%, p = 0.029*). No significant difference was found in vWF, fibrinogen and PAI-1 expression. Mean time to recanalize was higher in the high estrogen state group compared to the control group (57.8 ± 27.6 versus 22.6 ± 11.4 min, p = 0.0351*). The mean number of passes required was higher in the high estrogen group compared to controls 4.6 versus 1.2, p = 0.0261*). CONCLUSIONS: TAFI expression, a powerful driver of thrombosis, was significantly higher in stroke thrombi among patients with high estrogen states compared to controls.

Venous sinus stenting for idiopathic intracranial hypertension: An updated Meta-analysis.

BACKGROUND: Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure and primarily affects obese women of reproductive age. Venous sinus stenting (VSS) is a surgical procedure used to treat IIH, but its safety and efficacy are still controversial. METHODS: A systematic review and meta-analysis were conducted following PRISMA guidelines. Multiple databases were searched for studies evaluating the safety and efficacy of VSS in IIH patients and meta-analysis was performed to pool the data. RESULTS: A total of 36 studies involving 1066 patients who underwent VSS were included. After VSS, a significant reduction in trans-stenotic gradient pressure was observed. Patients also showed significantly lower cerebrospinal fluid (CSF) opening pressure. Clinical outcomes demonstrated improvement in tinnitus (95%), papilledema (89%), visual disturbances (88%), and headache (79%). However, 13.7% of patients experienced treatment failure or complications. The treatment failure rate was 8.35%, characterized by worsening symptoms and recurrence of IIH. The complications rate was 5.35%, including subdural hemorrhage, urinary tract infection, stent thrombus formation, and others. CONCLUSION: VSS appears to be a safe and effective treatment option for IIH patients who are unresponsive to medical therapy or have significant visual symptoms. However, long-term outcomes and safety of the procedure require further investigation.