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.

Intraluminal Flow Diverter Design Primer for Neurointerventionalists

The clinical use of flow diverters for the treatment of intracranial aneurysms has rapidly grown. Consequently, the market and technology for these devices has also grown. Clinical performance characteristics of the flow diverter are well-known to the clinician. However, the engineering design principles behind how these devices achieve ideal clinical performance are less understood. This primer will summarize flow diverter design parameters for neurointerventionalists with the aim of promoting collaboration between clinicians and engineers.

Impact analysis of primary and secondary research in radiology journals

INTRODUCTION

Primary and secondary studies are considered the two major research categories. In this study, we examined the scientific and social media impact of primary and secondary publication types in papers published radiological journals during 2010-2020.

MATERIALS AND METHODS

PubMed publication type tags were used to filter original articles and systematic review and meta-analysis (SR/MA) articles. Clarivate Web of Science was utilized to obtain a list of all radiology journals from the category "Radiology, Nuclear Medicine and Imaging" in Science Citation Index Expanded (SCIE). Automated approach was developed for programmatic extraction of bibliometric and Altmetric yearly citations of each included article using Dimensions API and Altmetric API with Python. Statistical analysis was performed to compare the citation rates between primary and secondary research articles.

RESULTS

A total of 96,684 published articles from 2010 to 2020 were identified and their meta-data collected. The mean 2-year citation count following publication year was 5.8 for primary research and 10.2 for SR/MA articles (p < 0.001). Between 2010 and 2020, the mean number of citations per SR/MA article was 51.3 compared to 30.5 per primary research article (p < 0.001). Mean Altmetric score was 8.2 in SR/MA compared to 3.7 for primary research articles (p < 0.001).

CONCLUSION

Secondary research studies have been increasing in impact in both academia and social media compared to primary research. Our results highlight the importance and impact of systematic reviews and meta-analysis articles as a scientifically influential study type in radiology.

The Effect of the COVID-19 Pandemic on Academic Research Gender Disparities in Radiology

RATIONALE AND OBJECTIVES

Gender disparities have long existed in radiology. The COVID-19 pandemic disrupted research activities worldwide and have impacted gender disparities across medical specialties. This study investigates the effect of the COVID-19 pandemic on gender disparities in radiology academic authorship.

MATERIALS AND METHODS

A retrospective observational study was conducted using data from 110 843 global and 23 977 US radiology articles. The gender of authors was determined using an automated gender inference tool. Descriptive statistics were applied to explore authorship changes overall globally, in the US as well as across countries and states.

RESULTS

Female first-authorship increased globally from 16.9% to 17.6% (p < 0.001), and in the US, from 19.0% to 19.6% (p = 0.19) in the peri-COVID period. The combined female percentage increased from 19.7% to 20.0% globally (p = 0.021), and from 20.2% to 21.1% in the US (p = 0.006). Country-level analysis revealed significant increases in female authorship in Colombia, Denmark, Egypt, France, India, and Japan, while New Zealand demonstrated a decrease in female authorship. In the US, Florida, Indiana, Louisiana, Massachusetts, and Ohio experienced increases in female authorship, whereas South Carolina demonstrated a decrease in female authorship.

CONCLUSION

In contrast with other medical fields, the study demonstrates that radiology experienced a slight increase in female authorship in radiology research globally and in the US during the COVID period. While the pandemic may have influenced these findings, further research is needed to establish regional causal relationships and identify best practices for promoting gender equity in radiology research.

Safety and efficacy profile of off-label use of the Pipeline Embolization Device: A systematic review and meta-analysis

OBJECTIVE

The off-label utilization of the Pipeline Embolization Device (PED) is a common practice in numerous medical centers globally. Therefore, we conducted a systematic review and meta-analysis to evaluate the overall outcomes of this off-label usage of PEDs.

METHODS

PubMed, Web of Science, Ovid Medline, Ovid Embase, and Scopus were searched up to February 2023 using the Nested Knowledge platform to identify studies assessing the off-label use of PEDs. Any use of PED outside of the FDA-approved indication granted in 2018 is considered off-label use. Overall angiographic occlusion rates, ischemic and hemorrhagic complications, mortality, retreatment rates, and favorable clinic outcomes were included. Statistical analyses were performed to compare the overall outcome rates of anterior cerebral artery(ACA) vs. middle cerebral artery(MCA) and anterior vs posterior circulation subgroups.

RESULTS

We included 26 studies involving a total of 1,408 patients. The overall rate of complete occlusion was 80.3 % (95 % CI= 76.0-84.1). Subgroup analysis demonstrated a statistically significant difference in the rate of complete occlusion between anterior circulation (78.9 %) and posterior circulation (69.2 %) (p value=0.02). The rate of good clinical outcomes was 92.8 % (95 % CI= 88.8-95.4). The mortality rate was 1.4 % (95 % CI= 0.5-2.7). The overall rate of ischemic complications was 9.5 % (95 % CI= 7.7-11.6), with a comparable difference between anterior circulation (7.7 %) and posterior circulation (12.8 %) (p value=0.07). There was no statistically significant difference in MCA vs ACA subgroups in all parameters.

CONCLUSIONS

Off-label use of PEDs can be a safe and effective treatment option for intracranial aneurysms. However, there is a need for more prospective, high-quality, non-industry-funded registry studies and randomized trials to test the efficacy and safety of off-label usage of PEDs and to expand its indications.

Theranostics and artificial intelligence: new frontiers in personalized medicine

The field of theranostics is rapidly advancing, driven by the goals of enhancing patient care. Recent breakthroughs in artificial intelligence (AI) and its innovative theranostic applications have marked a critical step forward in nuclear medicine, leading to a significant paradigm shift in precision oncology. For instance, AI-assisted tumor characterization, including automated image interpretation, tumor segmentation, feature identification, and prediction of high-risk lesions, improves diagnostic processes, offering a precise and detailed evaluation. With a comprehensive assessment tailored to an individual's unique clinical profile, AI algorithms promise to enhance patient risk classification, thereby benefiting the alignment of patient needs with the most appropriate treatment plans. By uncovering potential factors unseeable to the human eye, such as intrinsic variations in tumor radiosensitivity or molecular profile, AI software has the potential to revolutionize the prediction of response heterogeneity. For accurate and efficient dosimetry calculations, AI technology offers significant advantages by providing customized phantoms and streamlining complex mathematical algorithms, making personalized dosimetry feasible and accessible in busy clinical settings. AI tools have the potential to be leveraged to predict and mitigate treatment-related adverse events, allowing early interventions. Additionally, generative AI can be utilized to find new targets for developing novel radiopharmaceuticals and facilitate drug discovery. However, while there is immense potential and notable interest in the role of AI in theranostics, these technologies do not lack limitations and challenges. There remains still much to be explored and understood. In this study, we investigate the current applications of AI in theranostics and seek to broaden the horizons for future research and innovation.

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.

Journal selection guide for radiology case reports

Case reports and interesting images are valuable contributions to the radiology literature as they provide unique insights into uncommon conditions and rare presentations. Additionally, they serve as a rapidly expanding live image atlas and, therefore, can help radiologists to improve their diagnostics skills. However, due to high rejection rates and an increasing number of predatory publishers, publishing radiology case reports remains a daunting task for junior researchers. To overcome these challenges and ensure timely dissemination of their research findings, authors should consider several factors when selecting a target journal for case report publications. In this primer, we have summarized key considerations in journal selection and highlighted reputable journals that welcome radiology case reports.

Differences in outcome between left-sided and right-sided mechanical thrombectomy for acute ischemic stroke: A systematic review and meta-analysis

BACKGROUND

Mechanical thrombectomy (MT) is a safe and effective treatment option for acute ischemic stroke due to large vessel occlusion. To investigate differences in outcomes between patients receiving left-sided and right-sided MT, we performed a systematic review and meta-analysis.

METHODS

A systematic literature review was performed using Embase, PubMed, Scopus, and Web of Science databases. Additional literature was searched for manually. Studies reporting safety and efficacy metrics for MT were included. Data regarding the modified Rankin scale (mRS), thrombolysis in cerebral infarction (TICI), symptomatic intracranial hemorrhage (sICH), and 90-day mortality were included. A random-effects model was used to calculate pooled odds ratios (ORs), mean differences (MDs), and 95% confidence intervals (CIs).

RESULTS

The literature search yielded 13 reports consisting of 19 studies ranging from 98 to 5590 patients. Patients presenting with left-sided stroke had a National Institutes of health stroke scale score 2.89 greater than patients presenting with right-sided stroke (MD = 2.89; 95% CI = 2.09-3.68; P-value < 0.001). There were no differences between left-sided and right-sided MT patients for mRS 0-2 (OR = 0.94; 95% CI = 0.85-1.04; P-value = 0.224), TICI 2b-3 (OR = 1.05; 95% CI = 0.88-1.25; P-value = 0.598), sICH (OR = 0.83; 95% CI = 0.61-1.14; P-value = 0.255), or 90-day mortality (OR = 1.06; 95% CI = 0.84-1.33; P-value = 0.610).

CONCLUSIONS

There does not appear to be a difference in outcomes for patients undergoing left-sided or right-sided thrombectomy.

Quality Assessment of Radiomics Studies on Functional Outcomes After Acute Ischemic Stroke-A Systematic Review

OBJECTIVE

Radiomics is a machine-learning method that extracts features from medical images. The objective of the present systematic review was to assess the quality of existing studies that use radiomics methods to predict functional outcomes in patients after acute ischemic stroke.

METHODS

Studies using radiomics-extracted features to predict functional outcomes among patients with acute ischemic stroke using the modified Rankin Scale were included. PubMed, Scopus, Web of Science, and Embase were screened using the terms "radiomics" and "texture" in combination with "stroke." Quality scores were calculated based on Radiomics Quality Score, the IBSI (Image Biomarkers Standardization Initiative), and the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2).

RESULTS

Fourteen studies were included. The median total Radiomics Quality Score was 14.5 (13-16) out of 36. Domains 1, 5, and 6 on protocol quality and stability of imaging and segmentation, level of evidence, and use of open science and data, respectively, were poor. Median IBSI score was 2.5 (1-5) out of 6. Few studies included bias-field correction algorithms, isovoxel resampling, skull stripping, or gray-level discretization. Of 14 studies, none received +6 points, 1 received +5 points, 5 received +4 points, 1 study received +3 points, 5 received +2 points, 2 received +1 points, and none received 0 points. As per the QUADAS-2, 6/14 (42.9%) studies had a risk of bias concern and 0/14 (0%) had applicability concern.

CONCLUSIONS

The quality of the included studies was low to moderate. With increasing use of radiomics, future studies should attempt to adhere to and report established radiomics quality guidelines.

Common Design and Data Elements Reported on Idiopathic Intracranial Hypertension Trials: A Systematic Review

BACKGROUND

There are an increasing number of controlled clinical trials and prospective studies, ongoing and recently completed, regarding management options for idiopathic intracranial hypertension (IIH). We present a Common Design and Data Element (CDDE) analysis of controlled and prospective IIH studies with the aim of aligning essential design and recommending data elements in future trials and enhancing data synthesis potential in IIH trials.

METHODS

We used PubMed and ClinicalTrials.gov to screen for ongoing and published trials assessing treatment modalities in people with IIH. After our search, we used the Nested Knowledge AutoLit platform to extract pertinent information regarding each study. We examined outputs from each study and synthesized the data elements to determine the degree of homogeneity between studies.

RESULTS

The most CDDE for inclusion criteria was the modified Dandy criteria for diagnosis of IIH, used in 9/14 studies (64%). The most CDDE for outcomes was change in visual function, reported in 12/14 studies (86%). Evaluation of surgical procedures (venous sinus stenting, cerebrospinal fluid shunt placement, and others) was more common, seen in 9/14 studies (64%) as compared with interventions with medical therapy 6/14 (43%).

CONCLUSIONS

Although all studies have similar focus to improve patient care, there was a high degree of inconsistency among studies regarding inclusion criteria, exclusion criteria, and outcomes measures. Furthermore, studies used different time frames to assess outcome data elements. This heterogeneity will make it difficult to achieve a consistent standard, and thus, making secondary analyses and meta-analyses less effective in the future. Consensus on design of trials is an unmet research need for IIH.

Endovascular Embolization Techniques for Cerebrospinal Fluid-Venous Fistula in the Treatment of Spontaneous Intracranial Hypotension

Cerebrospinal fluid-venous fistula (CVF) is an important cause of spontaneous intracranial hypotension (SIH), a condition characterized by low cerebrospinal fluid (CSF) volume and orthostatic headaches. The pathogenesis of CVF is thought to be direct connection of the spinal dura to one or more veins in the epidural space, allowing unregulated flow of CSF into the venous system. Herein, we provide a comprehensive review of the endovascular management of CVF in patients with SIH. We also focus on the various techniques and devices used in endovascular treatment, as well as the pathogenesis, diagnosis, and alternative treatment options of CVF.

Effects of intravenous thrombolysis on stent retriever and aspiration thrombectomy outcomes: a systematic review and meta-analysis of the randomized controlled trials

BACKGROUND

Risks and benefits of intravenous thrombolysis (IVT) in patients undergoing mechanical thrombectomy (MT) have been a topic of interest. However, IVT's specific effects on stent retriever (SR) and aspiration thrombectomy (ASP) outcomes remain largely unexplored. In this meta-analysis, we aimed to investigate the effects of IVT on SR and ASP thrombectomy outcomes.

METHODS

In accordance with PRISMA guidelines, a systematic literature review was conducted using Medline, Embase, Scopus, Web of Science, and Cochrane Center of Clinical Trials databases. Outcomes of interest included successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b), modified first pass efficacy (mFPE), functional independence (modified Rankin Scale (mRS) ≤2), symptomatic intracranial hemorrhage (sICH), and embolization to new territories (ENT).

RESULTS

Four randomized controlled trials with 1176 patients were included. SR and ASP resulted in similar mTICI ≥2b, mFPE, and mRS 0-2 rates in patients with and without IVT administration. SR without IVT was associated with a significantly lower rate of mFPE compared with the SR+IVT (RR 0.85, 95% CI 0.74 to 0.97). Furthermore, ASP without IVT resulted in a lower rate of mRS 0-2 than the ASP+IVT with a strong trend towards significance (RR 0.78, 95% CI 0.60 to 1.01). Finally, bridging therapy did not increase sICH and ENT rates after ASP or SR thrombectomy.

CONCLUSIONS

Our findings suggest that SR and ASP thrombectomy have comparable safety and efficacy profiles, regardless of prior IVT administration. Additionally, our results indicate that the addition of IVT may improve certain efficacy outcomes based on the employed first-line MT technique.

Common design and data elements reported in active mechanical thrombectomy trials focusing on distal medium vessel occlusions and minor strokes: a systematic review

BACKGROUND

Distal medium vessel occlusions (DMVOs) and minor strokes represent emerging frontiers in mechanical thrombectomy (MT). Although several randomized clinical trials (RCTs) are underway, the design characteristics of these trials and the specific questions they aim to address have not been extensively explored. This current study sought to investigate the design and data elements reported in active prospective DMVO and minor stroke studies.

METHODS

The ClinicalTrials.gov database was searched for ongoing prospective studies assessing the role of MT in patients with DMVOs or minor strokes. The Nested Knowledge AutoLit platform was utilized to categorize reported outcomes and inclusion/exclusion criteria. Frequencies of reported data elements were extracted from study protocols.

RESULTS

A total of 10 (8 DMVO and 2 minor stroke) studies enrolling 3520 patients were included. All DMVO studies employ different criteria regarding target occlusion locations. Five DMVO studies use stent retrievers as the first-line thrombectomy technique (62.5%, 5/8), while three studies allow any MT techniques, generally at the operator's discretion. Four DMVO studies permit intravenous thrombolysis (IVT) utilization in both intervention and control arms (50%, 4/8). The DISTALS trial excludes patients receiving IVT, while the DUSK trial and Tigertriever registry only enroll patients who are ineligible for IVT or for whom IVT failed to achieve reperfusion. DMVO studies exhibit notable heterogeneity in symptom onset duration thresholds for inclusion (<6 hours: 2 studies; <12 hours: 2 studies; <24 hours: 3 studies). Minor stroke trials employ similar inclusion criteria and outcome measures except for symptom duration thresholds for inclusion (8 hours for ENDOLOW and 23 hours for MOSTE).

CONCLUSIONS

There is considerable heterogeneity among active DMVO trials regarding potential target DMVO locations and time thresholds for inclusion based on the last known well time. Furthermore, our review indicates that the utility of aspiration thrombectomy in DMVOs and the advantages of MT without IVT over IVT alone will remain largely unexplored even after completion of active DMVO trials.

Disability-free outcomes after mechanical thrombectomy: A systematic review and meta-analysis of the randomized controlled trials

BACKGROUND

The modified Rankin Scale (mRS) score of ≤2 (functional independence) has been the most common primary endpoint of modern mechanical thrombectomy (MT) trials. However, unlike mRS 0-1, mRS score of 2 indicates disability. An important proportion of the mRS 2 patients are home dependent and report a significant decrease in their quality of life.

PURPOSE

To investigate excellent outcome (mRS 0-1) rates after MT.

METHODS

We systematically searched Ovid MEDLINE, Ovid EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science databases. Randomized controlled trials (RCTs) investigating the role of modern MT in acute ischemic stroke were screened. Posterior circulation and large-core infarct trials were excluded from the study. The data regarding excellent outcomes (mRS: 0-1), functional independence (mRS: 0-2), and reperfusion were collected.

RESULTS

Twenty-two RCTs comprising 5692 patients were included in the meta-analysis. The overall mRS 0-1 rate was 31.24% (95% CI = 26.95-36.2). The rate of successful reperfusion was 81.8% (95% CI = 77.93-85.86). MT achieved significantly higher rates of mRS 0-1 compared to standard care alone (OR =  2.04; 95% CI = 1.64-2.55; P-value < 0.001), with no heterogeneity detected among studies (I2= 0%; P-value = 0.52). The direct MT and MT plus intravenous thrombolytic treatment groups' excellent outcome rates were comparable (OR =  0.98; 95% CI = 0.82-1.18; P-value = 0.863). Also, aspiration and stent retriever thrombectomy techniques provided similar excellent outcome rates (OR =  0.76; 95% CI = 0.55-1.05; P-value = 0.141).

CONCLUSIONS

Our results prove the additional benefit of MT over standard care, using a stricter definition for favorable functional outcome. Nearly one-third of patients presenting with large artery occlusion and treated with MT had no disability at 90 days. While this is remarkable, our results also indicate that reperfusion alone is often not enough to prevent disability and underline the need for better neuroprotection strategies.

Endovascular embolization of cerebrospinal fluid-venous fistula: a comprehensive systematic review on its efficacy and safety for the management of spontaneous intracranial hypotension

Cerebrospinal fluid (CSF)-venous fistula can cause spontaneous intracranial hypotension (SIH) and poses a significant diagnostic and management challenge. This study aims to provide a comprehensive overview of the clinical and radiological outcomes of endovascular embolization as a novel treatment approach for CSF-venous fistula in patients with SIH. This systematic review adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 statement. The primary outcome was the efficacy of the embolization procedure in occlusion of the CSF-venous fistula, and secondary outcomes included procedural complications and improvement of clinical symptoms and radiological findings. A total of nine studies consisting of 77 patients met the inclusion criteria. Orthostatic and/or Valsalva headache was the most common symptom. The mean age of the patients was 57 ± 8.9 years, and females accounted for 59.7% (46/77) of the cases. Sixty-five (84.4%) patients reported complete resolution or significant improvement in symptoms. The Bern score, Headache Impact Test-6, and the Patient Global Impression of Change scales demonstrated significant improvements in radiological findings and patients' quality of life. Following the procedure, 22 patients (28.6%) experienced rebound intracranial hypertension and 27 patients (35.1%) had transient local pain at the site of the embolization. Our study showed that endovascular embolization is a safe and effective treatment for CSF-venous fistula in patients with SIH, providing complete resolution or significant improvement of clinical symptoms and radiological findings, and positive impacts on patients' quality of life.

Mechanical Thrombectomy for In-Hospital Onset Stroke: A Comparative Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

In-hospital onset stroke (IHOS) accounts for a significant proportion of large vessel occlusion acute ischemic strokes, leading to worse outcomes due to delays in evaluation and treatment. Limited data is available on the effectiveness of mechanical thrombectomy in IHOS patients. This study aims to assess the safety and efficacy of mechanical thrombectomy for patients with IHOS and compare the outcomes with those of community-onset strokes (COS).

METHODS

We conducted a systematic review and meta-analysis following established guidelines, by searching PubMed, Scopus, Web of Science, and Embase databases up to April 11, 2023. Eligible studies reporting outcomes of interest were included, and relevant data was extracted and analyzed using Stata software version 17.0.

RESULTS

In a meta-analysis of nine studies, comprising 540 cases of IHOS and 5,744 cases of COS, IHOS cases had a significantly lower rate of good functional outcomes on follow-up (35.46% vs. 40.74%, P<0.01) and a higher follow-up mortality rate (26.29% vs. 18.08%, P<0.01) compared to COS patients. Both groups had comparable successful recanalization rates (IHOS: 79.32% vs. COS: 81.44%, P=0.11), incidence rates of periprocedural complications (IHOS: 15.10%, COS: 12.96%, P=0.78), and symptomatic intracranial hemorrhage (IHOS: 6.24%, COS: 6.88%, P=0.67). It is worth noting that much of the observed effect size for mortality and good functional outcomes on follow-up was derived from only one and two studies, respectively.

CONCLUSION

While the current literature suggests that mechanical thrombectomy is a safe and effective treatment for IHOS, further research is necessary to comprehensively evaluate its impact, particularly during follow-up.

Comparative analysis of syringes versus pump devices in benchtop aspiration thrombectomy models: A systematic review and meta-analysis

BACKGROUND

Although direct contact aspiration has emerged as one of the leading techniques for mechanical thrombectomy (MT), there is still ongoing debate about the aspiration/suction pump devices that can optimize recanalization rates. To address this gap, we conducted a meta-analysis comparing the aspiration efficacy of 60 ml syringe and pump devices in benchtop MT models.

METHODS

Systematic literature review was conducted using Medline, Embase, Web of Science, and Scopus in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Outcomes of interest included flow rate and vacuum pressure delivered by a 60 ml syringe and several aspiration pumps. We used a random effects model to calculate the mean difference (MD) with 95% confidence intervals (CIs) and a statistically significant difference was considered as a two-sided p-value of less than 0.05.

RESULTS

We included six benchtop studies comparing 60 ml syringes and vacuum pumps. Our meta-analysis showed that there were no significant differences in vacuum pressure (MD:0.71inHg, 95% CI: [-0.81;2.23], p = 0.359) and flow rate (MD:0.27 mL/s, 95% CI: [-3,07; 3.61], p = 0.873) between 60 ml syringes and vacuum pumps groups.

CONCLUSIONS

Our study demonstrated comparable performance in terms of vacuum pressure and flow rates between a 60 ml syringe and a heterogeneous combination of commercially available aspiration pumps.

Outcomes of mechanical thrombectomy in M1 occlusion patients with or without hyperdense middle cerebral artery sign: A systematic review and meta-analysis

BACKGROUND

The comparison of mechanical thrombectomy (MT) outcomes between patients with the hyperdense middle cerebral artery sign (HMCAS) and non-HMCAS is important to evaluate the impact of this radiological finding on treatment efficacy. This meta-analysis aimed to assess the association between HMCAS and clinical outcomes in patients undergoing thrombectomy, comparing the outcomes over non-HMCAS.

METHODS

A systematic literature search was conducted in PubMed, Ovid Embase, Google Scholar, and Cochrane Library to identify studies on MT outcomes for M1 occlusions of HMCAS over non-HMCAS. Inclusion criteria encompassed modified Rankin Scale (mRS) score, mortality, symptomatic intracranial hemorrhage (sICH), and successful recanalization. Using R software version 4.1.2, we calculated pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI).

RESULTS

The meta-analysis was performed for 5 studies with 724 patients. There was no association found between presence of HMCAS and achieving mRS 0-2 (OR = 0.65, 95% CI: 0.29-1.47; p = .544). Mortality analysis also showed no significant association with presence of HMCAS (OR = 0.78, 95% CI: 0.37-1.65; p = .520). No significant difference in sICH risk (OR = 1.54, 95% CI: 0.24-9.66; p = .646) was found between groups. Recanalization analysis showed a non-significant positive association (OR = 1.23, 95% CI: 0.67-2.28; p = .501). Heterogeneity was observed in all analyses.

CONCLUSION

Our findings showed that there is no statistically significant difference in mRS scores, mortality, sICH, and recanalization success rates between the HMCAS and non-HMCAS groups.

Embolization of arteriovenous malformations of head and neck: A systematic review

BACKGROUND

Cervicofacial arteriovenous malformations (AVMs) are a significant source of morbidity. Endovascular embolization has emerged as a promising treatment technique for these lesions. However, current literature on cervicofacial AVM embolization mostly consists of single-agent oriented case series, and to date, no comprehensive study has compared the outcomes of available embolic agents.

PURPOSE

To investigate the performance of different embolic agents in the management of cervicofacial AVMs.

METHODS

We systematically searched Ovid MEDLINE, Ovid EMBASE, Ovid Cochrane Central Register of Controlled Trials Scopus, and Web of Science. Studies providing data for the endovascular treatment of cervicofacial AVMs were included. The data regarding complication and cure rates were collected for each embolic agent. Pooled event rates were presented as descriptive statistics.

RESULTS

Eleven studies comprising 204 patients were included in the review. The overall complete and partial cure rates were 62.2% (127/204) and 36.2% (74/204), respectively. Embolization failed to achieve significant improvement in only 1.6% (3/204) of the patients. The complete cure rates were 87.5% (75-100%) for n-Butyl cyanoacrylate (NBCA, glue), 80.5% (61-100%) for Onyx (Medtronic, MN, USA), and 51.5% (18-85%) for ethanol. The overall complication rate was 30% (61/204). The complication rates were 33% (12.5-53%) for ethanol, 14% (0-28%) for Onyx, and 0% for NBCA.

CONCLUSIONS

Our systematic review supports that endovascular embolization is an effective treatment option for cervicofacial AVMs. In our review, the use of Onyx and NBCA was associated with consistently high complete cure rates and a promising safety profile. However, more research is needed to investigate the use of different embolic agents in the treatment of cervicofacial AVMs.

Quality assessment of histopathological stainings on prolonged formalin fixed thrombus tissues retrieved by mechanical thrombectomy

Background

Formalin-fixed retrieved clots from mechanical thrombectomy (MT) are now routinely studied using both conventional histopathologic techniques and immunohistochemistry (IHC). However, the effects of prolonged formalin fixation on the histological results of clot analysis remain unknown. The objective of this study was to investigate the effects of prolonged formalin fixation on quality of histopathologic stainings of thrombus tissues retrieved by MT.

Methods

As part of the multicenter EXCELLENT registry, a total of 80 clots extracted by MT from acute ischemic stroke patients were randomly selected from the tissue database and assigned into four groups according to 10% neutral buffered formalin (NBF) fixation duration (1-30, 30-60, 60-90, and 90+ days, up to 2 years). Samples underwent processing and sectioning. Two serial sections for each case were stained with hematoxylin and eosin (H&E), Martius Scarlet Blue (MSB), and IHC for CD42b (platelet marker). An expert pathologist, who was blinded to tissue fixation duration and patient clinical data, assessed the quality of each stain including stainability, sensitivity, specificity, and consistency of stainings.

Results

No significant issues were encountered during tissue processing and sectioning. On H&E stain, 97.5% (78/80) of slides showed good-quality staining, demonstrating clear histological properties of the thrombus tissue as red blood cells (RBC) stained in red, fibrin/platelet stained in pink, and nuclei stained in blue with intranuclear detail. The same histological features were also successfully demonstrated on MSB for all 80 samples. One of the 80 samples (1.2%) showed that RBC lost stainability on H&E due to tissue autolysis. Clear positive signal of platelet staining was expressed in 98.8% of the samples (79/80) with minimal background staining on IHC. There was no significant difference in staining quality across different formalin fixation groups.

Conclusion

A good quality of histopathological staining is achievable for the thrombus tissue fixed in 10% neutral buffered formalin for up to 2 years. The findings are limited to the thrombus tissue retrieved by MT and specific fixation and staining protocols used in the study. To apply these results to other tissue or experimental setups, further studies and validations would be necessary.

Clinical trial registration

This study was conducted as part of the EXCELLENT study: www.clinicaltrials.gov, unique identifier: NCT03685578.

Zilver stent versus Carotid Wallstent for endovascular treatment of idiopathic intracranial hypertension

BACKGROUND

Venous sinus stenting (VSS) is a promising treatment option for medically refractory idiopathic intracranial hypertension (IIH). There are no published studies comparing the performance of different types of stents employed in VSS procedures. In this study we aimed to compare the safety and efficacy outcomes of the Zilver 518 (Cook Medical, Bloomington, Indiana, USA) and the Carotid Wallstent (Boston Scientific, Marlborough, Massachusetts, USA) devices.

METHODS

Records of patients with IIH who underwent VSS between January 2015 and February 2022 at a single referral center were retrospectively reviewed. Patients treated with the Zilver stent or Carotid Wallstent were included in the study. Stent model and size data, pre- and post-treatment pressure gradients, technical and safety outcomes, and pre- and post- stenting papilledema, headache, and tinnitus severity were collected. The χ2 and Fisher-Freeman-Halton tests were used for categorical data and the Student's t-test and Mann-Whitney U test were employed to examine the differences in non-categorical variables.

RESULTS

A total of 81 procedures (28 (34.5%) with the Zilver stent and 53 (65.5%) with the Carotid Wallstent) were performed in 76 patients. The mean procedure time was significantly shorter with the Zilver stent (22.56±10.2 vs 33.9±15 min, p=0.001). The papilledema improvement and resolution rates did not significantly differ between groups (94.7% vs 94.5%, p>0.99 for improvement; 78.9% vs 67.5%, p=0.37 for resolution). The tinnitus improvement and resolution rates in the Zilver stent group were significantly higher than those of the Carotid Wallstent group (100% vs 78.9%, p=0.041; 90% vs 63.1%, p=0.03, respectively). Additionally, the Zilver stent provided a significantly higher rate of headache resolution and improvement than the Carotid Wallstent (84.6% vs 27.6%, p=0.001 for resolution; 92.3% vs 72.3%, p=0.043 for improvement). One patient from the Carotid Wallstent group underwent re-stenting due to in-stent stenosis and refractory papilledema. No significant in-stent stenosis was observed in the Zilver stent group.

CONCLUSION

Stent choice may affect VSS outcomes. The Zilver stent provided better clinical outcomes than the Carotid Wallstent, with significantly shorter procedure times. Larger studies are needed to determine the efficacy of available venous stents for IIH.

Distal versus conventional transradial access for diagnostic cerebral angiography and neurointerventional procedures: A systematic review and meta-analysis

BACKGROUND

Distal transradial artery access (dTRA) has received increasing consideration for performing diagnostic cerebral angiography and neurointerventional procedures. In this meta-analysis, we aim to evaluate the safety and efficacy of dTRA compared to conventional transradial access (cTRA) for cerebral angiography and neurointerventions.

METHOD

A systematic review and meta-analysis were conducted on studies investigating outcomes of dTRA and cTRA in neurointerventions. The primary outcome was technical success rates. Secondary outcomes included access site complication rates, crossover rates to alternative vessels, fluoroscopy time, and contrast volume. The random effects model was used to calculate the mean difference (MD) and odds ratios (OR) with 95% confidence intervals (Cl).

RESULTS

Eight retrospective observational studies with a total of 1477 patients who underwent 1175 diagnostic cerebral angiography and 516 neurointerventional procedures using 546 dTRA and 1164 cTRA approaches were included in our meta-analysis. The technical success rate was similar between dTRA and cTRA groups (95.8% vs 91.4%; OR:1.65; 95% Cl: 0.52 to 5.22; P = 0.40). Similarly, no difference was seen in dTRA and cTRA regarding access site complications (2% vs 1.4%; OR: 1.31; 95% CI: 0.47 to 3.61; P = 0.61) and access site crossover (2.1% vs 5.3%; OR: 0.55; 95% Cl: 0.28 to 1.05; P = 0.07). After resolving heterogeneity among included studies, dTRA was associated with a shorter fluoroscopy time (MD: -0.91 min; 95% CI: -1.74 to -0.09; P = 0.03) and lower contrast volume (MD: -8.32 mL; 95% CI = -14.7 to -1.94; P = 0.011).

CONCLUSION

Our findings suggest that the dTRA approach is a safe and effective alternative to the cTRA approach in patients undergoing cerebral angiography and neurointerventions.

Comparison of balloon guide catheter versus non-balloon guide catheter for mechanical thrombectomy in patients with distal medium vessel occlusion

BACKGROUND

Several studies have established the safety and efficacy of balloon guide catheters (BGCs) for large vessel occlusions. However, the utility of BGCs remains largely unexplored for distal medium vessel occlusions (DMVOs). In this study, we aim to compare the outcomes of BGC vs. Non-BGC in patients undergoing mechanical thrombectomy (MT) for DMVO.

METHOD

This retrospective study from the Stroke Thrombectomy and Aneurysm Registry (STAR) encompassed adult patients with acute anterior cerebral artery, posterior cerebral artery, and middle cerebral artery-M2-3-4 occlusions. Procedure times, safety, recanalization, and neurological outcomes were compared between the two groups, with subgroup analysis based on first-line thrombectomy techniques.

RESULTS

A total of 1508 patients were included, with 231 patients (15.3%) in the BGC group and 1277 patients (84.7%) in the non-BGC group. The BGC group had a lower modified Thrombolysis in Cerebral Infarction (mTICI) score ≥2C (43.2% vs 52.7%, P=0.01), longer time from puncture to intracranial access (15 vs 8 min, P<0.01), and from puncture to final recanalization (97 vs 34 min, P<0.01). In the Solumbra subgroup, the first pass effect (FPE) rate was lower in the BGC group (17.4% vs 30.7%, P=0.03). Regarding clinical outcomes, the BGC group had a lower rate of distal embolization (8.8% vs 14.9%, P=0.03).

CONCLUSION

Our study found that use of BGC in patients with DMVO was associated with lower mTICI scores, decreased FPE rates, reduced distal embolization, and longer procedure times.

Catheter design primer for neurointerventionalists

Neurovascular catheter technology has rapidly evolved over the past decade. While performance characteristics are well known to the practitioner, the design features of these new-generation catheters and their implications on performance metrics remain a mystery to most clinicians due to the limited number of available resources. This knowledge gap hampers informed device choices and also limits collaboration between clinicians and engineers. To aid fellow neurointerventionalists, in this primer we have summarized the basic concepts of catheter design and construction.

DWI-Detected Ischemic Lesions after Endovascular Treatment for Cerebral Aneurysms: An Updated Systematic Review and Meta-analysis

BACKGROUND AND PURPOSE

DWI-detected ischemic lesions are potential complications of endovascular procedures that are performed to treat intracranial aneurysms. We completed a systematic review and meta-analysis to identify the occurrence of DWI-detected ischemic lesions after endovascular treatment for intracranial aneurysms.

MATERIALS AND METHODS

A systematic literature search of PubMed, the Web of Science, EMBASE, and Scopus between January 2000 and June 2022 of post-endovascular procedures for intracranial aneurysm studies was conducted using the Nested Knowledge AutoLit software. The main outcome was DWI-detected ischemic lesions within 5 days of the procedures. Information regarding associated risk factors such as the type of procedure, patient demographics, and aneurysm characteristics was also collected.

RESULTS

Twenty-nine studies with 2686 patients were included. The overall incidence of DWI ischemic lesions was 47.0% (95% CI, 39.6%-55.8%). The highest rate of lesions was seen with flow diversion at 62.4% (95% CI, 48.4%-80.5%), followed by complex procedures at 49.3% (95% CI, 29.5%-82.1%), stent-assisted coiling at 47.5% (95% CI, 34.6%-65.3%), simple coiling at 47.1% (95% CI, 35.7%-62.3%), and balloon-assisted coiling at 37.0% (95% CI, 28.3%-48.4%). The differences among different techniques were not statistically significant; however, there was significant heterogeneity and a significant risk of publication bias among included studies.

CONCLUSIONS

Many patients who undergo endovascular procedures for intracranial aneurysms present with new postprocedural DWI-detected ischemic lesions, regardless of the endovascular procedure used. Future studies and meta-analyses are needed to investigate early and long-term outcomes of such small infarcts.

Aneurysmal recurrence and retreatment modalities after Woven EndoBridge (WEB) device implantation: A systematic review and meta-analysis

BACKGROUND

The Woven EndoBridge (WEB) device is used to treat wide-neck bifurcation aneurysms (WNBAs). We conducted a systematic review and meta-analysis to determine the retreatment rate strategies following aneurysmal recurrence of WEB device treated WNBAs.

METHODS

This study is reported following the PRISMA 2020 guidelines. We conducted a systematic review of the literature using PubMed, Scopus, Embase, and Web of Science. Data were pooled using a random-effects model. We calculated pooled prevalence and corresponding 95% confidence intervals (CI).

RESULTS

We included 11 studies. The overall retreatment rate was 171/1875 aneurysms (10.3%; 95% CI  =  8.3-12.9). Stent-assisted coiling was used to treat 59 aneurysms (36.7%; 95% CI  =  26.4-48.5), and flow diverters were used to treat 44 aneurysms (18.7%; 95% CI  =  9.9-32.5). Following retreatment, the complete occlusion rate was 57/91 aneurysms (62.8%; 95% CI  =  48.2-75.3) and the adequate occlusion rate was 24/91 aneurysms (26.4%; 18.4%-36.4%). The most common aneurysmal recurrence site was the anterior communicating artery (44/136 aneurysms, 32.4%; 95% CI  =  25.0-40.7).

CONCLUSIONS

Roughly 10% of WNBAs initially treated with the WEB device will undergo retreatment. Retreatment is an effective strategy for WEB-treated aneurysms, with high rates of adequate and complete occlusion. Future studies should work to identify risk factors for aneurysmal recurrence.

Comparative and Predictive Analysis of Clinical and Metabolic Features of Anorexia Nervosa and Bulimia Nervosa

Background

Eating disorders have become increasingly prevalent over the years; the age at which they appear has decreased, and they can lead to serious illness or death. Therefore, the number of studies on the matter has increased. Eating disorders like anorexia nervosa (AN) and bulimia nervosa (BN) are affected by many factors including mental illnesses that can have serious physical and psychological consequences. Accordingly, the present study aimed to compare the clinical and metabolic features of patients with AN and BN and identify potential biomarkers for distinguishing between the two disorders.

Methods

Clinical data of 41 participants who sought treatment for eating disorders between 2012 and 2022, including 29 AN patients and 12 BN patients, were obtained from NPIstanbul Brain Hospital in Istanbul, Turkey. The study included the clinical variables of both outpatient and inpatient treatments. Principal component analysis (PCA) was utilized to gain insights into differentiating AN and BN patients based on clinical characteristics, while machine learning techniques were applied to identify eating disorders.

Findings

The study found that thyroid hormone levels in patients with AN and BN were influenced by non-thyroidal illness syndrome (NTIS), which could be attributed to various factors, including psychiatric disorders, substance abuse, and medication use. Lipid profile comparisons revealed higher triglyceride levels in the BN group (P<0.05), indicating increased triglyceride synthesis and storage as an energy source. Liver function tests showed lower levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in BN patients (P<0.05), while higher prolactin levels (P<0.05) suggested an altered hypothalamic-pituitary-gonadal axis. Imbalances in minerals such as calcium and magnesium (P<0.05) were observed in individuals with eating disorders. PCA effectively differentiated AN and BN patients based on clinical features, and the Naïve Bayes (NB) model showed promising results in identifying eating disorders.

Conclusion

The findings of the study provide important insights into AN and BN patients' clinical features and may help guide future research and treatment strategies for these conditions.

First-pass effect in posterior acute ischemic stroke undergoing endovascular thrombectomy: A systematic review and meta-analysis

OBJECTIVES

First-pass effect (FPE) has been shown to be a predictor of favorable clinical outcomes following endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) in the anterior circulation. Literature regarding FPE for posterior circulation AIS is sparse; we conducted a systematic review and meta-analysis to explore FPE in posterior circulation stroke undergoing EVT.

MATERIALS AND METHODS

We conducted a systematic review of the English literature in PubMed, Embase, Scopus, and Web of Science. FPE was defined as thrombolysis in cerebral infarction (TICI) 2c-3 and modified FPE (mFPE) was defined as TICI 2b-3 in one pass. Definitions of non-FPE and non-mFPE varied among studies. The primary outcome of interest was modified Rankin Scale (mRS) 0-2. Secondary outcomes of interest were mRS 0-3, symptomatic intracranial hemorrhage (sICH), and mortality. We calculated odds ratios (OR) and corresponding 95% confidence intervals (CI). Heterogeneity was assessed with Q statistic and I2 test.

RESULTS

Seven studies with 417 patients in the mFPE group, 942 in the non-mFPE group, 545 in the FPE group, and 1023 in the non-FPE group were included. Overall, FPE was associated with greater rates of 90-day mRS 0-2 (OR= 2.78, 95% CI= 2.11-3.65; P-value< 0.001) and mRS 0-3 (OR= 2.67, 95% CI= 1.98-3.60; P-value< 0.001); however, there was significant heterogeneity among studies for both mRS 0-2 (I2= 69%; P-value< 0.001) and mRS 0-3 (I2= 69%; P-value< 0.001). FPE and non-FPE were associated with similar rates of sICH (OR= 0.65, 95% CI= 0.40-1.07; P-value= 0.09), and no heterogeneity was observed (I2= 0%; P-value= 0.95). FPE was associated with lower rates of mortality (OR= 0.44, 95% CI= 0.33-0.58; P-value< 0.001), although heterogeneity was observed (I2= 58%; P-value= 0.01).

CONCLUSIONS

FPE is associated with favorable clinical outcomes in patients undergoing EVT for posterior circulation AIS. Future studies should work to further quantify the impact of FPE on outcomes in the posterior circulation.

Long-term outcomes of flow diversion for unruptured intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

Flow diverters have been widely used in clinical practice for more than a decade. However, most outcome data are limited to 1 year timepoints. This study aims to offer meta-analysis data on long-term (>1 year) safety and effectiveness results for patients with aneurysms treated with flow diverters.

METHODS

PubMed, Web of Science, Embase, and SCOPUS were searched up to February 24, 2022 using the AutoLit platform. We included primary studies assessing the long-term outcomes for flow diverter devices to manage unruptured internal carotid artery aneurysms with a follow-up period of >1 year. The meta-analysis was carried out using Comprehensive Meta-Analysis software (CMA).

RESULTS

Eleven studies were included in the meta-analysis. The pooled occlusion rates after flow diversion treatment for unruptured intracranial brain aneurysms were 77%, 87.4%, 84.5%, 89.4%, 96% for 1 year, 1-2 years, 2 years, 3 years, and 5 years follow-up, respectively. The in-stent stenosis rate was 4.8% and the retreatment rate for the long-term follow-up period was 5%. No delayed rupture of the aneurysm was reported, and there was one case of delayed ischemic stroke. The sensitivity analysis of the prospective studies showed a complete occlusion rate of 83.5% and 85.2% for 1 and 3 years of follow-up, respectively.

CONCLUSION

Flow diverters are safe and effective in short- and long-term follow-up and rarely cause serious delayed side effects.

Mechanical Thrombectomy for Pediatric Large Vessel Occlusions : A Systematic Review and Meta-analysis

BACKGROUND

Acute intracranial large vessel occlusion (LVO) is an important cause of morbidity and mortality among children; however, unlike in adults, no clinical trial has investigated the benefit of mechanical thrombectomy (MT) in pediatric LVO. Thus, MT remains an off-label procedure for pediatric stroke.

PURPOSE

To investigate the efficacy and safety of MT in pediatric LVO.

METHODS

A systematic literature search was conducted in Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, and Cochrane Central Register of Clinical Trials databases. Studies reporting safety and efficacy outcomes for endovascular treatment of pediatric LVO were included. Data regarding recanalization, functional outcome, symptomatic intracranial hemorrhage (sICH), and mortality were extracted from the included studies. Functional outcome was assessed with the modified Rankin scale (mRS). A fixed or random-effects model was used to calculate pooled event rates and 95% confidence intervals (CI).

RESULTS

In this study 11 studies comprising 215 patients were included. The successful recanalization rate was 90.3% (95% CI = 85.77-95.11%), and complete recanalization was achieved in 52.7% (95% CI = 45.09-61.62%) of the cases. The favorable (mRS = 0-2) and excellent (mRS = 0-1) outcome rates were 83.3% (95% CI = 73.54-94.50%) and 59.5% (95% CI = 44.24-80.06%), respectively. The overall sICH prevalence was 0.59% (95% CI = 0-3.30%) and mortality rate was 3.2% (95% CI = 0.55-7.38%).

CONCLUSION

In our meta-analysis, MT demonstrated a promising safety and efficacy profile for pediatric patients, with consistently high efficacy outcomes and low complication rates. Our results support the utilization of MT in pediatric LVOs; however, prospective studies are still needed to further establish the role of pediatric MT as a first-line treatment strategy.

Middle meningeal artery embolization without surgical evacuation for chronic subdural hematoma: a single-center experience of 209 cases

Background

Middle meningeal artery (MMA) embolization is a minimally invasive treatment option for new and recurrent chronic subdural hematomas (cSDH).

Objective

To examine the safety and efficacy profile of MMA embolization without surgical evacuation for cSDH patients.

Methods

A single-center retrospective study of patients with cSDHs treated by MMA embolization was undertaken. Patient demographics, hematoma characteristics, procedural details, and clinical and radiological outcomes were collected. The primary outcome was the need for retreatment, and the secondary outcomes were at least a 50% reduction in the maximum width of cSDH on the last CT imaging, complications, and an improvement in the modified Rankin scale (mRS) score. All results were presented as descriptive statistics.

Results

A total of 209 MMA embolizations were successfully performed on 144 patients. Polyvinyl alcohol particles were the primary embolization agent in all procedures. Of the total of 206 cSDH, the median maximum width at pre-intervention and last follow-up were 12 and 3 mm, respectively, and the median reduction percentage was 77.5%, with a >50% improvement observed in 72.8% at the last follow-up imaging. A total of 13.8% of patients needed retreatment for recurrent, refractory, or symptomatic hematomas after embolization. The mRS score improved in 71 (49.3%) patients. Of 144 patients, 4 (2.8%) experienced complications related to the procedure, and 12 (8.4%) died during follow-up due to causes unrelated to the MMA embolization procedures.

Conclusion

This study supports the fact that MMA embolization without surgical evacuation is a safe and effective minimally invasive option for the treatment of cSDHs.

A review of acute ischemic stroke caused by distal, medium vessel occlusions

Acute ischemic stroke (AIS) due to distal, medium vessel occlusion (DMVO) is increasingly recognized as the next frontier for mechanical thrombectomy. Distal, medium vessel occlusions are typically defined as an occlusion in the following arteries: anterior cerebral artery, M2-M4 segments of the middle cerebral artery, posterior cerebral artery, posterior inferior cerebellar artery, anterior inferior cerebellar artery, and superior cerebellar artery. It is estimated that 25-40% of all AIS is due to DMVO. Because of the large burden of DMVO, the frequency of literature published regarding these occlusions has greatly increased in recent years. Furthermore, treatment modalities have been created specifically for DMVOs. Due to the rapidly evolving literature on this topic, remaining up to date on DMVO definitions, anatomy, management, imaging, and clinical course is difficult. In this review article, we synthesized existing literature regarding the aforementioned topics and discussed future directions.

Middle meningeal artery embolization combined with surgical evacuation for chronic subdural hematoma: A single-center experience of 75 cases

BACKGROUND

Chronic subdural hematoma (cSDH) is a challenging and common neurosurgical condition. Our goal is to demonstrate that middle meningeal artery (MMA) embolization combined with surgical evacuation can be a promising adjuvant option for treatment of cSDHs and prevent recurrence in symptomatic patients who require surgical treatment.

METHOD

We retrospectively collected data from patients who underwent MMA embolization using polyvinyl alcohol particles and surgical evacuation with burr hole or craniotomy in a single center for the treatment of new and recurrent cSDHs. The primary outcome was recurrence of cSDH requiring surgical rescue during follow up, and secondary outcomes were defined as >50% decrease in the maximum width of cSDHs on the longest follow-up computed tomography (CT) scan, complications following procedure, and improvement in modified Rankin scale (mRS) score.

RESULTS

A total of 51 patients successfully underwent 72 MMA embolization procedures (96% of the total 75 cases in the cohort) combined with surgical evacuation. Seventy cases (93.3%) achieved at least 50% reduction in the size of the cSDHs on the last CT imaging. A surgical evacuation was required in five cases (6.7%) due to cSDH recurrence during the follow-up period. There were three complications (6.0%) related to embolization procedure. Forty patients (78.4%) showed improvement in mRS score. There was one mortality (2%) regardless of the embolization and evacuation.

CONCLUSIONS

Our study demonstrates the safety and efficacy of adjunct MMA embolization in significantly reducing size and recurrence of cSDHs.

Endovascular treatment outcomes of vertebrobasilar junction aneurysms: Systematic review and meta-analysis

BACKGROUND

Vertebrobasilar junction (VBJ) aneurysms represent a relatively rare and often anatomically complex subgroup of saccular aneurysms. This systematic review and meta-analysis aimed to assess the safety and efficacy of endovascular treatment (EVT) of VBJ aneurysms.

METHODS

PubMed, Web of Science, Ovid Medline, Ovid Embase, and Scopus were searched from inception to 20 December 2022. We included primary studies assessing the long-term clinical and angiographic outcomes for VBJ aneurysms treated with endovascular techniques. We excluded surgically managed studies. All data were analyzed using R software version 4.2.1. We calculated pooled prevalence rates and their corresponding 95% confidence intervals (CI).

RESULTS

In this meta-analysis, a total of 76 VBJ aneurysms from seven studies were included for quantitative analysis. The results showed that the rate of adequate occlusion (complete + near complete occlusion) was 94.1% (95% CI = 76.71-98.71), and the rate of complete occlusion was 77.7% (95% CI = 63.07-87.65). A modified Rankin Scale (mRS) score of 0-2 was achieved in 93.9% of patients (95% CI = 67.65-99.14). The mortality rate was found to be 5.9% (95% CI = 0.97-28.55), and the retreatment rate was 4.6% (95% CI = 1.50-13.36). The overall ischemic complication rate was 4.7% (95% CI = 0.73-25.4), while the overall hemorrhagic complication rate was 4.6% (95% CI = 1.5-13.36).

CONCLUSIONS

The treatment of VBJ aneurysms with EVT is effective in achieving curative treatment and is associated with good clinical outcomes and low mortality rates. These findings provide important insights into the clinical and angiographic outcomes and the complication rates of EVT for VBJ aneurysms.

2b Or 2c-3? A meta-analysis of first pass thrombolysis in cerebral infarction 2b vs multiple pass thrombolysis in cerebral infarction 2c-3 following mechanical thrombectomy for stroke

BACKGROUND

Procedural success following mechanical thrombectomy for acute ischemic stroke is assessed using the thrombolysis in cerebral infarction scale. We conducted a systematic review and meta-analysis to determine whether outcomes differed between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3.

METHODS

We conducted a systematic review of the literature using PubMed, Embase, Scopus, and Web of Science. We included original studies in which outcomes were stratified based on first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. The primary outcome of interest was the rate of modified Rankin Scale 0-2. Secondary outcomes of interest were rates of modified Rankin Scale 0-1, symptomatic intracranial hemorrhage, and mortality. We calculated odds ratios and corresponding 95% confidence intervals.

RESULTS

Four studies with 1554 patients were included in the quantitative analysis. Rate of modified Rankin Scale 0-2 (odds ratio = 0.91, 95% confidence interval = 0.70-1.18; P-value = 0.49), modified Rankin Scale 0-1 (odds ratio = 1.21, 95% confidence interval = 0.86-1.71; P-value = 0.27), symptomatic intracranial hemorrhage (odds ratio = 1.36, 95% confidence interval = 0.47-3.98; P-value = 0.57), and mortality (odds ratio = 0.91, 95% confidence interval = 0.67-1.25; P-value = 0.56) did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. There was no heterogeneity among included studies for modified Rankin Scale 0-2, modified Rankin Scale 0-1, or mortality; however, there was moderate heterogeneity among studies for symptomatic intracranial hemorrhage (I2 = 53%, P-value = 0.12).

CONCLUSIONS

Clinical and safety outcomes did not differ between first pass thrombolysis in cerebral infarction 2b and multiple pass thrombolysis in cerebral infarction 2c-3. Future prospective studies and clinical trials should determine whether first pass thrombolysis in cerebral infarction 2b is a viable endpoint to thrombolysis in cerebral infarction 2c-3.

Phenox HPC and Phenox flow modulation devices for the endovascular treatment of intracranial aneurysms: a systematic review and meta-analysis

BACKGROUND

Surface-modified flow diverters are increasingly used in clinical settings. However, their safety profiles and additional benefits over non-coated devices still need to be explored. In this meta-analysis, we aimed to investigate and compare the clinical outcomes of the uncoated Phenox and coated Phenox HPC flow diverters.

METHODS

A systematic literature review was performed using PubMed, Scopus, Embase, and Web of Science databases. Collected data were pooled and corresponding 95% confidence intervals (CI) were calculated. Outcomes of interest included aneurysm occlusion (>6 months) and complication rates. Additionally, the safety outcomes of prophylactic single (SAPT) and dual antiplatelet treatment (DAPT) approaches were compared for patients treated with coated Phenox HPC flow diverters.

RESULTS

We included 17 studies with 1238 patients. The overall complete occlusion rates were 80% (95% CI 74.01% to 86.56%) for Phenox HPC and 71.3% (95% CI 59.71% to 85.20%) for non-coated Phenox flow diverters (p=0.24). Ischemic complication rates were 7.3% (95% CI 4.6% to 11.39%) with the Phenox HPC and 5.3% (95% CI 4.07% to 6.91%) with the Phenox (p=0.24). For patients treated with Phenox HPC, the SAPT (5.5%; 95% CI 2.83% to 10.85%) and DAPT (7.1%; 95% CI 1.23% to 41.45%) approaches resulted in comparable ischemic complication rates (p=0.79). The DAPT group (4.8%; 95% CI 1.46% to 16.24%) had higher hemorrhagic complication rates than the SAPT group (1.7%; 95% CI 0.52% to 6.09%), but the difference was not statistically significant for patients treated with Phenox HPC (p=0.25).

CONCLUSIONS

Our findings indicate that Phenox HPC is equally as safe and effective as non-coated Phenox devices. Additionally, our results suggest that prasugrel monotherapy might effectively prevent ischemic complications in patients treated with Phenox HPC flow diverters.

Impact of branch arteries on efficacy of endoluminal flow diverters: Insights from posterior communicating artery aneurysms

BACKGROUND

Flow diverter treatment may inevitably require jailing of the branch vessels. While the patency of covered branch arteries and associated safety risks have been a topic of substantial interest, the question of whether the characteristics of branch vessels affect flow diversion's efficacy remains unanswered. In this study, we aimed to assess the impact of branch arteries on the efficacy of endoluminal flow diverters, specifically focusing on posterior communicating artery (Pcomm) aneurysms.

METHODS

Following PRISMA guidelines, we systematically searched the MEDLINE, EMBASE, Scopus, Web of Science, and Cochrane databases with predefined keywords. Studies providing data for flow diversion outcomes in Pcomm aneurysms were included. Outcomes of interest included complete and adequate aneurysm obliteration, ischemic and hemorrhagic complications, and Pcomm occlusion in the follow-up period. A random or fixed effects model was used to calculate the odds ratios (ORs) and pooled event rates with their corresponding confidence intervals (CI).

RESULTS

The overall complete and adequate aneurysm occlusion rates were 72.25% (95% CI: 64.46-78.88%) and 88.37% (95% CI: 84.33-92.6), respectively. Fetal-type Pcomm aneurysms had significantly lower complete aneurysm occlusion rates than the nonfetal-type Pcomm aneurysms (OR: 0.12, 95% CI: 0.05-0.29). Overall ischemic and hemorrhagic complication rates were 2.62% (95% CI = 0.71-5.32) and 0.71% (95% CI: 0-2.24), respectively. There were no significant associations between Pcomm morphology and complications (OR: 3.61, 95% CI = 0.42-31.06 for ischemic complications and OR: 2.31, 95% CI = 0.36-14.6 for hemorrhage). Overall Pcomm occlusion rate was 32.04% (95% CI = 19.96-47.13), and the Pcomm patency was significantly lower in nonfetal-type Pcomm aneurysms (OR: 0.10, 95% CI = 0.02-0.44).

CONCLUSION

Our meta-analysis suggests that flow diversion is a safe treatment option for Pcomm aneurysms, regardless of fetal-type Pcomm morphology. However, on the other hand, our findings indicate that Pcomm anatomy or the presence of jailed large branches can affect the efficacy of flow diverter treatment.

Benchtop proof of concept and comparison of iron- and magnesium-based bioresorbable flow diverters

OBJECTIVE

Bioresorbable flow diverters (BRFDs) could significantly improve the performance of next-generation flow diverter technology. In the current work, magnesium and iron alloy BRFDs were prototyped and compared in terms of porosity/pore density, radial strength, flow diversion functionality, and resorption kinetics to offer insights into selecting the best available bioresorbable metal candidate for the BRFD application.

METHODS

BRFDs were constructed with braided wires made from alloys of magnesium (MgBRFD) or iron (FeBRFD). Pore density and crush resistance force were measured using established methods. BRFDs were deployed in silicone aneurysm models attached to flow loops to investigate flow diversion functionality and resorption kinetics in a simulated physiological environment.

RESULTS

The FeBRFD exhibited higher pore density (9.9 vs 4.3 pores/mm2) and crush resistance force (0.69 ± 0.05 vs 0.53 ± 0.05 N/cm, p = 0.0765, n = 3 per group) than the MgBRFD, although both crush resistances were within the range previously reported for FDA-approved flow diverters. The FeBRFD demonstrated greater flow diversion functionality than the MgBRFD, with significantly higher values of established flow diversion metrics (mean transit time 159.6 ± 11.9 vs 110.9 ± 1.6, p = 0.015; inverse washout slope 192.5 ± 9.0 vs 116.5 ± 1.5, p = 0.001; n = 3 per group; both metrics expressed as a percentage of the control condition). Last, the FeBRFD was able to maintain its braided structure for > 12 weeks, whereas the MgBRFD was almost completely resorbed after 5 weeks.

CONCLUSIONS

The results of this study demonstrated the ability to manufacture BRFDs with magnesium and iron alloys. The data suggest that the iron alloy is the superior material candidate for the BRFD application due to its higher mechanical strength and lower resorption rate relative to the magnesium alloy.

First-line thrombectomy strategy for carotid terminus occlusions: A systematic review and meta-analysis

Background

Little research has focused on the performance of mechanical thrombectomy (MT) in carotid terminus occlusions (CTOs). Therefore, the best first-line thrombectomy strategy for CTOs remains unclear.

Purpose

To compare the safety and efficacy outcomes of three first-line thrombectomy techniques in CTOs.

Methods

A systematic literature search was conducted in Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, and Cochrane Central Register of Clinical Trials databases. Studies providing safety and efficacy outcomes for endovascular treatment of CTOs were included. Data regarding successful recanalization, functional independence, symptomatic intracranial hemorrhage (sICH), and first pass efficacy (FPE) were extracted from the included studies. A random-effects model was used to calculate prevalence rates and their corresponding 95% confidence intervals (CI), and subgroup analyses were performed to assess the impact of the initial MT technique on safety and efficacy outcomes.

Results

Six studies with 524 patients were included. The overall successful recanalization rate was 85.84% (95% CI = 77.96-94.52), and subgroup analysis did not show a significant difference among the three first-line MT techniques. Overall rates of functional independence and FPE were 39.73% (95% CI = 32.95-47.89) and 32.09% (95% CI = 22.93-44.92), respectively. The combined stent retriever (SR) and aspiration (ASP) technique achieved significantly higher first-pass efficacy rates compared to SR or ASP alone. The overall sICH rate was 9.89% (95% CI = 4.88-20.07), and subgroup analysis did not demonstrate a significant difference across groups. The sICH rates of SR, ASP, and SR + ASP were 8.49% (95% CI = 1.76-40.93), 6.8% (95% CI = 4.59-10.09), and 7.12% (95% CI = 0.27-100), respectively.

Conclusions

Our results support that MT is highly effective for CTOs with functional independence rates of 39%. Additionally, in our meta-analysis, the SR + ASP technique was associated significantly greater rates of FPE compared to SR or ASP alone, without an increase in sICH rates. Prospective, large-scale studies are necessary to determine the optimal first-line MT technique in the endovascular treatment of CTOs.

Long-term outcomes of the Woven EndoBridge device for treatment of intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

The Woven EndoBridge (WEB) has been specifically developed to manage wide neck bifurcation intracranial aneurysms. A wide range of aneurysm occlusion rates and device-related complications are reported in different papers, and a lack of collective evidence in this regard.

OBJECTIVE

To clarify the long-term efficacy and safety outcomes of intracranial aneurysm treatment with WEB devices.

METHODS

A systematic literature search was performed on PubMed, Scopus, Web of Science, and Embase databases on April 25, 2023. Considering the eligibility criteria, all the studies reporting the outcomes of the intracranial aneurysm treatment with WEB device at 1 and/or more than 1 year were included. Data elements of interest were extracted and analyzed using R software version 4.2.1.

RESULTS

Twenty-seven articles were included. Complete occlusion rate was 56.85%, 67.10%, and 56.34% at one year, beyond one year, and at/beyond two years of follow-up, respectively. Adequate occlusion rate was 87.11% at one year, 91.16% beyond one year, and 88.87% at/beyond two years of follow-up. WEB compression and aneurysm recurrence rates increased from 17.62% and 0.58% at one year to 42.59% and 18.99% beyond one year of follow-up, respectively. An increase in retreatment rate from 3.45% at one year to 7.15% beyond one year of follow-up was found.

CONCLUSION

The current study supports the long-term efficacy of WEB devices for the treatment of intracranial aneurysms. However, an increase in WEB compression, aneurysm recurrence, and retreatment rates beyond one year reveals the importance of follow-ups after the first year of WEB placement.

Medical Imaging Compatibility of Magnesium- and Iron-Based Bioresorbable Flow Diverters

BACKGROUND AND PURPOSE

Bioresorbable flow diverters are under development to mitigate complications associated with conventional flow-diverter technology. One proposed advantage is the ability to reduce metal-induced artifacts in follow-up medical imaging. In the current work, the medical imaging compatibility of magnesium- and iron-based bioresorbable flow diverters is assessed relative to an FDA-approved control in phantom models.

MATERIALS AND METHODS

Bioresorbable flow diverters, primarily composed of braided magnesium or antiferromagnetic iron alloy wires, were compared with an FDA-approved control flow diverter. The devices were assessed for MR imaging safety in terms of magnetically induced force and radiofrequency heating using 1.5T, 3T, and 7T field strength clinical scanners. The devices were deployed in phantom models, and metal-induced image artifacts were assessed in the 3 MR imaging scanners and a clinical CT scanner following clinical scan protocols; device visibility was assessed under fluoroscopy.

RESULTS

The magnesium-based bioresorbable flow diverter, iron-based bioresorbable flow diverter, and the control device all demonstrated MR imaging safety in terms of magnetically induced force and radiofrequency heating at all 3 field strengths. The bioresorbable flow diverters did not elicit excessive MR imaging artifacts at any field strength relative to the control. Furthermore, the bioresorbable flow diverters appeared to reduce blooming artifacts in CT relative to the control. The iron-based bioresorbable flow diverter and control device were visible under standard fluoroscopy.

CONCLUSIONS

We have demonstrated the baseline medical imaging compatibility of magnesium and antiferromagnetic iron alloy bioresorbable flow diverters. Future work will evaluate the medical imaging characteristics of the bioresorbable flow diverters in large-animal models.

The safety profile of single antiplatelet therapy with flow diverters: Systematic review and meta-analysis

BACKGROUND

Dual antiplatelet therapy (DAPT) is frequently used in treating cerebral aneurysms with flow diverters (FDs), whereas single antiplatelet therapy (SAPT) is used mostly with coated FDs and in ruptured aneurysms. We conducted a systematic review and meta-analysis to explore the safety profile of SAPT in FDs.

METHODS

PubMed, Web of Science, OVID Embase, OVID Medline, and Scopus were searched to 1st November 2022. Outcomes of interest included ischemic and hemorrhagic complications, conversion to DAPTs, and in-stent stenosis rates under long-term SAPT. SAPT is divided into aspirin (ASA) vs. non-ASA group (ticagrelor or prasugrel). Subgroup analysis was performed for ruptured vs. non-ruptured aneurysms and coated vs. non-coated FDs. All data were analyzed using R software version 4.2.2.

RESULTS

Twelve studies with 240 total patients (43 patients in the ASA group and 197 patients in the non-ASA group) were included in our meta-analysis. The pooled ischemic occlusion rate was 9.8% (95% CI = 4.87-18.95: p-value = 0.09) for SAPTs. The ASA group had significantly higher ischemic complication rates compared to the non-ASA group (20.8% vs. 6.3%, respectively, p-value = 0.02). The pooled hemorrhagic complication rate was 3.5% (95% CI = 1.38-8.81: p-value > 0.99). The hemorrhagic rates of ASA group were 9.3%% (95% CI = 3.54-22.30) over the non-ASA group 2.1% (95% CI = 0.58-7.54) (p-value > 0.99). The overall in-stent stenosis rate was 2.3% (95% CI = 1.06-5.14: p-value > 0.99). The ischemic complication rates were comparable between coated vs non-coated FDs (10.7% vs. 5.5% p-value = 0.39). In stent stenosis rate were 1.9% (95% CI = 0.72-4.96) in coated FDs over 4.4% (95% CI = 1.11-16.11) (p-value = 0.32). The ruptured and non-ruptured groups also showed comparable results in terms of ischemic (17.6% vs. 7.1% respectively, p-value = 0.24) and hemorrhagic complications (9.8% vs. 1.1%, respectively, p-value = 0.08).

CONCLUSIONS

Flow diverter treatment under ASA monotherapy resulted in relatively high ischemic complication rates. However, SAPT with prasugrel or ticagrelor monotherapy is promising for coated FDs and ruptured aneurysm treatments. Given the overall small sample size and also the likely presence of known and unknown biases regarding choice of antiplatelet therapy between groups, larger cohort studies are needed to evaluate SAPT treatment outcomes.

Differences between males and females following endovascular therapy for stroke: A systematic review and meta-analysis

BACKGROUND

Endovascular therapy (EVT) represents the standard of care for eligible patients with acute ischemic stroke (AIS) and large vessel occlusion. To better understand differences in baseline characteristics and outcomes between males and females following EVT, we conducted a systematic review and meta-analysis.

METHODS

We identified, using the Nested Knowledge AutoLit platform, prospective studies that reported 90-day outcomes in males and females treated with EVT for AIS. The primary outcome of interest was 90-day modified Rankin Scale (mRS) 0-2. Secondary outcome variables included mRS 0-1, symptomatic intracranial hemorrhage (sICH), thrombolysis in cerebral infarction (TICI) score 2b-3, and mortality. Using R software version 4.1.2, we calculated pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI).

RESULTS

We included 10 studies with 10,209 patients. There was no difference between males and females in rate of mRS 0-2 (OR= 1.16; 95% CI= 0.87-1.56; P-value= 0.316); however, after removing outliers, males had higher rates of mRS 0-2 (OR= 1.40; 95% CI= 1.19-1.66; P-value< 0.001). Similar results were reported for mRS 0-1 (OR= 1.21; 95% CI= 0.93-1.56; P-value= 0.15), after removing outliers (OR= 1.32; 95% CI= 1.17-1.50; P-value< 0.001). There was no difference between males and females in rate of sICH (OR= 0.89; 95% CI= 0.74-1.08; P-value= 0.246), mortality (OR= 0.88; 95% CI= 0.74-1.05; P-value= 0.15), or TICI 2b-3 (OR= 1.19; 95% CI= 0.85-1.67; P-value= 0.309).

CONCLUSIONS

Males tend to experience better outcomes following EVT for AIS, even in the setting of similar reperfusion. The mechanisms underlying this phenomenon remain unclear, and further research is warranted. EVT remains a safe and effective option for both males and females with AIS.

CT Perfusion vs Noncontrast CT for Late Window Stroke Thrombectomy: A Systematic Review and Meta-analysis

BACKGROUND

Patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT) in the late window (6-24 hours) can be evaluated with computed tomography perfusion (CTP) or with noncontrast computed tomography (NCCT) only. Whether outcomes differ depending on type of imaging selection is unknown. We conducted a systematic review and meta-analysis comparing outcomes between CTP and NCCT for EVT selection in the late therapeutic window.

METHODS

This study is reported according to the PRISMA 2020 guidelines. A systematic literature review of the English language literature was conducted using Web of Science, Embase, Scopus, and PubMed databases. Papers focusing on late window AIS undergoing EVT imaged via CTP and NCCT were included. Data were pooled using a random-effects model. The primary outcome of interest was rate of functional independence, defined as modified Rankin Scale (mRS) 0-2. Secondary outcomes of interest included rates of successful reperfusion, defined as thrombolysis in cerebral infarction (TICI) 2b-3, mortality, and symptomatic intracranial hemorrhage (sICH).

RESULTS

Five studies with 3,384 patients were included in our analysis. There were comparable rates of functional independence (OR= 1.03, 95% CI, 0.87-1.22; P-value= 0.71) and sICH (OR= 1.09, 95% CI, 0.58-2.04; P-value= 0.80) between the two groups. Patients imaged with CTP had higher rates of successful reperfusion (OR= 1.31, 95% CI, 1.05-1.64; P-value= 0.015) and lower rates of mortality (OR= 0.79, 95% CI, 0.65-0.96; P-value= 0.017).

CONCLUSIONS

Although recovery of functional independence after late window EVT was not more common in patients selected by CTP as compared to patients selected by NCCT only, patients selected by CTP had lower mortality.

Determining flow stasis zones in the intracranial aneurysms and the relation between these zones and aneurysms' aspect ratios after flow diversions

BACKGROUND

Flow diverter stents (FDSs) are widely used to treat aneurysms in the clinic. However, even the same flow diverter (FD) use on different patients' aneurysm sites can cause unexpected hemodynamics at the aneurysm region yielding low success rates for the overall treatment. Therefore, the present study aims to unfold why FDs do not work as they are supposed to for some patients and propose empirical correlation along with a contingency table analysis to estimate the flow stasis zones in the aneurysm sacs.

METHODS

The present work numerically evaluated the use of FRED4518 FDS on six patients' intracranial aneurysms based on patient-specific aneurysm geometries. Computational fluid dynamics (CFD) simulation results were further processed to identify the time evolution of weightless blood particles for six patients' aneurysms.

RESULTS

Stagnation zone formation, incoming and outgoing blood flow at the aneurysm neck, and statistical analysis of six patients indicated that FRED4518 showed a large flow stasis zone for an aspect ratio larger than 0.75. However, FRED4518, used for aneurysms with an aspect ratio of less than 0.65, caused small stagnant flow zones based on the number of blood particles that stayed in the aneurysm sac.

CONCLUSION

A patient-specific empirical equation is derived considering aneurysms' morphological characteristics to determine the amount of stagnated fluid flow zones and magnitude of the mean aneurysm velocity in the aneurysm sac for FRED4518 based on weightless fluid particle results for the first time in the literature. As a result, numerical simulation results and patient data-driven equation can help perceive stagnated fluid zone amount before FRED4518 placement by shedding light on neuro-interventional surgeons and radiologists.

Abstract Number ‐ 95: Common Data Elements Analysis of Mechanical Thrombectomy Clinical Trials for Acute Ischemic Large Core Stroke

Introduction

Various clinical trials addressing large core acute ischemic stroke (AIS) are ongoing from multiple international groups. Future development of clinical guidelines depends on meta‐analyses of these trials calling for a degree of homogeneity of elements across the different studies. The aim of this common data element study was to provide an overview of the key features of pertinent large core infarct trials.

Methods

PubMed and ClinicalTrials.gov databases were screened for published and ongoing clinical trials assessing mechanical thrombectomy in patients with AIS with large core infarct. Nested Knowledge AutoLit living review platform was utilized to categorize primary and secondary outcomes as well as inclusion and exclusion criteria for patient selection in the clinical trials.

Results

The most reported data element was ASPECTS score, but with varied definitions of what compromises large core. Non‐utility‐weighted modified Rankin Score (mRS) was reported in 6/7 studies as the primary outcome, while the utility‐weighted mRS was the outcome of interest in the TESLA trial, all of them at the 3‐months mark, with only LASTE looking for mRS shift at the 6‐months mark. Secondary outcomes had more variations. Mortality is reported separately only in 4/7 trials, all at the 3‐month mark. Additionally, the TENSION trial reports the frequency of serious adverse events, including mortality, at the 1‐week and 12‐month mark.

Conclusions

In the published and the ongoing large core trials, there is a large degree of variability in the collected data elements. Differences in definition and timepoints renders reaching a unified standard difficult, which hinders high quality meta‐analyses and cohesive evidence‐driven synthesis.

Are we improving? Temporal trends in outcomes for mechanical thrombectomy for stroke: A systematic review and meta-analysis of randomized trials

BACKGROUND

In 2015, mechanical thrombectomy (MT) was deemed the standard of care for acute ischemic stroke (AIS) in the anterior circulation due to large vessel occlusion (LVO). To determine if outcomes in patients treated with MT have changed, we conducted a systematic review and meta-analysis of published randomized controlled trials (RCTs).

METHODS

A systematic literature review of the English language literature was conducted using PubMed. We included RCTs that focused on patients with AIS treated with MT. The primary outcome of interest was good functional outcome defined as modified Rankin Scale (mRS) 0-2 at 90 days. Safety outcomes included rates of symptomatic intracranial hemorrhage (sICH) and mortality at 90 days. Using Joinpoint Regression Analysis Program, we calculated the average annual percent change (AAPC) for the outcomes of interest.

RESULTS

We included 23 RCTs with 5784 patients. The years of mid-enrollment among the included RCTs ranged from 2012-2020. There was an AAPC of +3.82% between 2012 and 2020 (95% CI 0.4 to 7.3; P-value = 0.033) in rates of good functional outcome. There was an AAPC of +6.98% between 2012 and 2020 (95% CI 0.5 to 13.9; P-value = 0.039) in rates of sICH. There was an AAPC of -0.49% between 2012 and 2020 (95% CI -4.4 to 3.5; P-value = 0.77) in rates of mortality.

CONCLUSION

Between 2012 and 2020, rates of good functional outcome and sICH increased, while rates of mortality remained consistent in RCTs investigating MT for AIS. Multiple factors likely influenced our results, including increased use of MT and utilization of adjunctive therapies alongside MT.

Packing density and the angiographic results of coil embolization of intracranial aneurysms: A systematic review and meta-analysis

BACKGROUND

Endovascular coil embolization (ECE) for intracranial aneurysms has been proven as an effective minimally invasive treatment. However, the aneurysm recanalization after coiling is a serious complication of this technique. Among all the proposed factors associated with recanalization, the impact of packing density (PD) is still controversial.

OBJECTIVE

To clarify the role of PD in the aneurysm recanalization following ECE, via conducting a systematic review and meta-analysis.

METHODS

A systematic literature search was conducted using PubMed, Scopus, Embase, and Web of Science databases, until November 28, 2022, by adhering to the Preferred Reporting Items for Systematic Review and Meta-Analyses statement guidelines. Considering the eligibility criteria, all the studies reporting the outcomes of interest were included. Data elements of interest were extracted and analyzed using R software version 4.2.1.

RESULTS

The pooled analysis of the 17 eligible papers revealed a 29% higher PD of the nonrecanalized aneurysms (ROM = 1.29, 95% confidence interval [CI] = 1.18-1.40, p < 0.001), even after removing outlier studies to reduce heterogeneity. However, the pooled estimates from multivariable regression models within nine included studies showed no significant effect of PD on recanalization odds when incorporated into a multivariable model with other predictors (odds ratio [OR] = 0.93, 95% CI = 0.84-1.02, p = 0.126), even after removing outlier studies.

CONCLUSION

The current literature does not support PD as a significant predictor of aneurysm treatment outcomes, especially with adjusting for other variables. This finding necessitates further prospective multicenter studies with a larger sample size to overcome the current methodological shortcomings.

Mechanical thrombectomy alone versus with thrombolysis for ischemic stroke: A meta-analysis of randomized trials

INTRODUCTION

Mechanical thrombectomy (MT) is the standard of care in eligible patients presenting with acute ischemic stroke (AIS). The question of whether intravenous thrombolysis (IVT) improves outcomes in conjunction with MT remains unanswered. We performed a systematic review and meta-analysis of published randomized controlled trials (RCT) to explore outcomes of MT with and without IVT.

METHODS

Following the PRISMA guidelines, a systematic literature review of the English language literature was conducted using PubMed, Embase, Web of science, and Scopus. Outcomes of interest included 90-day modified Rankin Scale (mRS) 0-2, thrombolysis in cerebral infarction (TICI) score 2b-3, symptomatic intracranial hemorrhage (sICH), distal embolization, and mortality. We calculated pooled risk ratios (RRs) and their corresponding 95% confidence intervals (CI).

RESULTS

Six RCTs with 2334 patients compared outcomes of patients treated with MT alone and MT with IVT. Both treatments resulted in comparable rates of mRS 0-2 (RR = 0.96, 95% CI = 0.88-1.04; p-value = 0.282), sICH (RR = 0.80, 95% CI = 0.55-1.17; p-value = 0.253), mortality at 90-days (RR = 1.06, 95% CI = 0.88-1.28; p-value = 0.529), and distal embolization (RR = 1.10, 95% CI = 0.79-1.52; p-value = 0.572). MT alone was associated with a lower rate of TICI 2b-3 compared to MT with IVT (RR = 0.96, 95% CI = 0.93-0.99; p-value = 0.006).

CONCLUSIONS

In this meta-analysis of six RCTs, MT alone was comparable to MT plus IVT for mRS 0-2, sICH, mortality, and distal embolization; however, MT alone resulted in lower rates of TICI 2b-3. Further trials are needed to determine which patient populations benefit from MT plus IVT and to increase the power of future meta-analyses.