Endovascular thrombectomy for DAWN- and DEFUSE-3 ineligible acute ischemic stroke patients: a systematic review and meta-analysis

BACKGROUND

Endovascular therapy (EVT) has been proven beneficial for treating acute ischemic strokes (AIS) with large vessel occlusion (LVO). Recent trials of DAWN and DEFUSE-3 have extended the treatment window to 6-24 h, sparking investigations into EVT outcomes for patients not eligible for DAWN/DEFUSE-3 criteria.

PURPOSE

To assess the outcomes of endovascular therapy (EVT) for late-window anterior circulation large vessel occlusion (LVO) in acute ischemic stroke patients, comparing DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND) groups.

METHODS

This systematic review and meta-analysis examined EVT outcomes for patients with late-window anterior circulation LVO beyond 6 h. We categorized patients as DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND). Our search covered PubMed, Embase, Web of Science, and Scopus. A total of 464 records were initially identified. After duplicate removal, 298 studies were screened. Nine studies were included and analyzed. Our analysis focused on study characteristics, baseline comparisons, risk of bias, and outcomes.

RESULTS

Baseline characteristics showed comparable age, gender, most comorbidities, NIHSS score, and ASPECTS between DAWN/DEFUSE-3 eligible (DD) and ineligible (NDND) patients. NDND patients' history showed a higher rate of atrial fibrillation and larger infarct volumes on baseline imaging. Successful reperfusion rates (TICI 2b-3) were similar between DD and NDND with 354 out of 469 in the DD group and 364 out of 459 in the NDND group (OR = 0.86; 95% CI 0.40, 1.84; p = 0.689), though with significant heterogeneity (I2 = 73%; P = 0.002). The proportion of patients with distal occlusions was significantly higher in the NDND group as compared to the DD group (137 (39.4%) of 347 patients versus 47 (11%) of 428 patients, respectively), with significant heterogeneity across studies (I2 = 85%, p = 0.023). Functional independence at 90 days (mRS 0-2) showed no significant difference between groups with 259 out of 802 in the DD group and 197 out of 668 in the NDND group (OR = 1.12; 95% CI 0.77, 1.63; p = 0.552) but also exhibited notable heterogeneity (I2 = 46%, p = 0.063). Symptomatic intracranial hemorrhage (sICH) rates were lower in DD with 14 out of 309 in the DD group and 47 out of 400 in NDND group (OR = 0.49; 95% CI 0.25, 0.93; p = 0.029) as compared to the NDND patients, showing no heterogeneity (I2 = 0%, p = 0.552). 90-day mortality was lower in DD with 43 out of 304 in the DD group and 107 out of 399 in the NDND group (OR = 0.55; 95% CI 0.37, 0.82; p = 0.004) as compared to NDND patients, with no significant heterogeneity (I2 = 0%, p = 0.536).

CONCLUSION

This meta-analysis demonstrates equivalent rates of functional independence between DD and NDND patients. However, the high proportion of distal occlusions and higher rates of sICH and mortality in NDND patients suggest caution in offering mechanical thrombectomy to DAWN/DEFUSE-3 ineligible patients. A more flexible approach to EVT eligibility criteria could benefit select patients in real-world practice. Nonetheless, further research is needed to identify which patients would benefit from expanded EVT eligibility criteria.

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

BACKGROUND

Mechanical Thrombectomy (MT) has improved outcomes in acute ischemic stroke (AIS) due to Large Vessel Obstruction (LVO). However, there is limited data on the safety and outcomes of MT in AIS patients with thrombocytopenia. This study aims to assess the efficacy and safety of MT in this population.

METHODS

Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus. Studies meeting inclusion criteria underwent rigorous risk of bias assessment using the ROBINS-I tool. We compared outcomes between patients with and without thrombocytopenia undergoing MT. Using the R software version 4.3.1, meta-analyses were conducted employing random-effect models.

RESULTS

This meta-analysis encompassed data from 5 studies. Thrombocytopenic AIS patients who underwent MT (n = 974) exhibited lower rates of functional independence (OR 0.83, 95% CI 0.71-0.98; p = 0.030) compared to patients with normal platelet counts (n = 2036). In addition, the thrombocytopenic group experienced higher mortality as compared to the group with normal platelet counts (OR 1.76, 95% CI 1.26-2.45; p < 0.001). Rates of sICH were found to be similar between groups (OR 1.20, 95% CI 0.74-1.93; p = 0.456), as were rates of successful recanalization (OR 0.94, 95% CI 0.47-1.87; p = 0.863). Lastly, no significant differences were observed in procedure times between thrombocytopenic and non-thrombocytopenic groups.

CONCLUSION

As compared to patients without thrombocytopenia, thrombocytopenic AIS patients undergoing MT displayed lower functional independence and higher mortality rates, with no significant differences in sICH or successful recanalization.

Clot composition and recanalization outcomes in mechanical thrombectomy

BACKGROUND

Mechanical thrombectomy (MT) has become standard for large vessel occlusions, but rates of complete recanalization are suboptimal. Previous reports correlated radiographic signs with clot composition and a better response to specific techniques. Therefore, understanding clot composition may allow improved outcomes.

METHODS

Clinical, imaging, and clot data from patients enrolled in the STRIP Registry from September 2016 to September 2020 were analyzed. Samples were fixed in 10% phosphate-buffered formalin and stained with hematoxylin-eosin and Martius Scarlett Blue. Percent composition, richness, and gross appearance were evaluated. Outcome measures included the rate of first-pass effect (FPE, modified Thrombolysis in Cerebral Infarction 2c/3) and the number of passes.

RESULTS

A total of 1430 patients of mean±SD age 68.4±13.5 years (median (IQR) baseline National Institutes of Health Stroke Scale score 17.2 (10.5-23), IV-tPA use 36%, stent-retrievers (SR) 27%, contact aspiration (CA) 27%, combined SR+CA 43%) were included. The median (IQR) number of passes was 1 (1-2). FPE was achieved in 39.3% of the cases. There was no association between percent histological composition or clot richness and FPE in the overall population. However, the combined technique resulted in lower FPE rates for red blood cell (RBC)-rich (P<0.0001), platelet-rich (P=0.003), and mixed (P<0.0001) clots. Fibrin-rich and platelet-rich clots required a higher number of passes than RBC-rich and mixed clots (median 2 and 1.5 vs 1, respectively; P=0.02). CA showed a trend towards a higher number of passes with fibrin-rich clots (2 vs 1; P=0.12). By gross appearance, mixed/heterogeneous clots had lower FPE rates than red and white clots.

CONCLUSIONS

Despite the lack of correlation between clot histology and FPE, our study adds to the growing evidence supporting the notion that clot composition influences recanalization treatment strategy outcomes.

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

BACKGROUND

Idiopathic intracranial hypertension (IIH) is characterized by elevated intracranial pressure and primarily affects obese women of reproductive age. Venous sinus stenting (VSS) is a surgical procedure used to treat IIH, but its safety and efficacy are still controversial.

METHODS

A systematic review and meta-analysis were conducted following PRISMA guidelines. Multiple databases were searched for studies evaluating the safety and efficacy of VSS in IIH patients and meta-analysis was performed to pool the data.

RESULTS

A total of 36 studies involving 1066 patients who underwent VSS were included. After VSS, a significant reduction in trans-stenotic gradient pressure was observed. Patients also showed significantly lower cerebrospinal fluid (CSF) opening pressure. Clinical outcomes demonstrated improvement in tinnitus (95%), papilledema (89%), visual disturbances (88%), and headache (79%). However, 13.7% of patients experienced treatment failure or complications. The treatment failure rate was 8.35%, characterized by worsening symptoms and recurrence of IIH. The complications rate was 5.35%, including subdural hemorrhage, urinary tract infection, stent thrombus formation, and others.

CONCLUSION

VSS appears to be a safe and effective treatment option for IIH patients who are unresponsive to medical therapy or have significant visual symptoms. However, long-term outcomes and safety of the procedure require further investigation.

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

BACKGROUND

Wide neck bifurcation aneurysms (WNBAs) are a subtype of aneurysms that are especially complex to treat. We aim to conduct a systematic review and meta-analysis to synthesize the available literature on the safety and efficacy of employing endovascular clip system (eCLIPs) in the treatment of WNBAs.

METHODS

We report this study in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 guidelines. PubMed, Embase, Web of Science, and Scopus were queried for this review. Screening and extraction were performed by at least two authors to ensure accuracy and completeness, and a senior author arbitrated any discrepancies. All data were analyzed using R software version 4.3.0. and random-effects model.

RESULTS

Four studies were finally included, of which three were prospective and one was retrospective. Successful adjunctive coiling occurred in 91.38% (95% CI = 70.71-97.9) of cases and overall technical success was achieved in 88.61% (95 CI = 75.54-95.15) of cases. The pooled complete occlusion (Raymond-Roy Class I) was 50.65% (95% CI = 39.63-61.60) and adequate occlusion (Raymond-Roy Class I/II) was 84.42% (95% CI = 74.53-90.93). Thrombo-embolic complication had a pooled rate of 1.22% (95% CI = 0.17-8.15), retreatment rate was 6.10% (95% CI = 2.56-13.83), and mortality reported in 3.66% (95% CI = 1.18-10.74) of patients.

CONCLUSION

The use of eCLIPs may be a safe and efficacious treatment for WNBAs. Future randomized controlled trials are needed for further validation of the findings.

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

OBJECTIVES

Stroke is a leading cause of mortality and disability globally, with limited treatment options available for acute ischemic stroke (AIS) patients. Type 2 diabetes mellitus (T2DM) is not only widespread but also a known risk factor for stroke. Our meta-analysis aims to assess the influence of pre-stroke metformin use on the clinical outcomes in AIS patients with T2DM.

MATERIALS AND METHODS

We conducted this study following PRISMA guidelines, searching the following databases: Medline, Embase, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials up to February 29, 2024. All studies providing separate data on AIS patients using metformin were included, and statistical analysis was conducted using R software to pooled odds ratios (ORs) and their corresponding 95% confidence intervals (CI).

RESULTS

Out of 1051 studies, 7 met the inclusion criteria for our meta-analysis with a total of 11589 diabetic patients, including 5445 patients taking metformin and 6144 diabetic patients in the non-metformin group. Compared to the non-metformin group, the metformin group had a significantly higher rate of mRS 0-2 score at discharge (OR 1.56; 95% CI 1.25:1.95; p=< 0.01) and a lower rate of 90-day mortality (OR 0.51; 95% CI 0.42:0.61; p=< 0.01), with no significant difference in sICH (OR 0.88; 95% CI 0.47:1.64; p= 0.68) between the two groups.

CONCLUSIONS

Our meta-analysis demonstrated that pre-stroke metformin use is associated with higher functional independence and lower mortality in AIS patients with T2DM.

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.

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

BACKGROUND

The effective treatment for acute ischemic stroke (AIS) patients with cervical internal carotid pseudo-occlusion (cICA-PO) requires comprehensive research on the safety and outcomes of endovascular thrombectomy (EVT). However, there is limited data available, highlighting the need for further research to ensure better treatment strategies and improve the quality of care for these patients.

PURPOSE

This study aims to assess the management and outcomes in this population group compared to patients with true carotid occlusion.

DATA SOURCES

Following the PRISMA guidelines, a comprehensive systematic review was conducted using PubMed, Embase, Web of Science, and Scopus from data base inception to November 2023.

STUDY SELECTION

The size of the included studies ranged from 16 patients to 146 patients. Through the 4 full-text articles, a total of 259 patients were collected. We compared outcomes between patients with cICA-PO compared to patients with true carotid occlusions undergoing EVT due to AIS. We excluded studies with patients with carotid pseudo-occlusion without stroke, review articles, duplicate studies, overlapped data that included the same patients presented in another included study, case reports, case series with fewer than 5 patients, and meeting abstracts that did not contain the outcomes of interest. We did not pose any limitations regarding sample size or patients' characteristics.

DATA ANALYSIS

We utilized the R statistical software (V.4.3.1; R package meta, R Foundation for Statistical Computing, Vienna, Austria) to conduct the analysis of all the data obtained. We calculated the odds ratio (OR) for binary variables, and the corresponding 95% confidence interval (CI). To synthesize the data, random-effect models, as well as forest plots were generated to visually represent the synthesis of the data. Additionally, we assessed heterogeneity using Cochran's Q and I2 tests. A P-value less than 0.05 for the Q statistic or I2 more than 50% suggests significant heterogeneity. Based on a small number of studies (less than 10), the assessment of publication bias could not be reliably performed.

DATA SYNTHESIS

This meta-analysis encompassed data from 4 studies. Patients with cICA-PO and AIS who underwent EVT (n = 135) exhibited lower rates of functional independence (OR 0.35, 95% CI 0.20-0.61, p= <0.001) compared to patients with true occlusions (n = 103), as well as successful recanalization rates (OR 0.39, 95% CI 0.20-0.74, p=0.004). In addition, the cICA-PO group experienced higher mortality and sICH compared to the group with true carotid occlusions (OR 2.62, 95% CI 0.21-7.24, and OR 2.23, 95% CI 1.00-4.95, p= 0.049, respectively).

LIMITATIONS

Individual patient data was not available. Studies were a retrospective design and some of the studies had small sample sizes. The included studies in our metaanalysis did not exclude patients with tandem occlusions which might influence the results of the comparison.

CONCLUSIONS

As compared to patients with true carotid occlusion, the cICA-PO group with AIS undergoing EVT presented poor outcomes with lower functional independence and successful recanalization, as well as higher sICH and mortality rates.

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.

Endovascular outcomes for anterior choroidal artery aneurysms: systematic review and meta-analysis

BACKGROUND

Anterior choroidal artery (AchoA) aneurysms are relatively rare compared to other types of aneurysms. However, the occurrence of transient or permanent occlusion of the choroidal artery during endovascular or surgical treatment is an uncommon but potentially serious complication. In this study, we aim to investigate the safety and efficacy profile of endovascular treatment (EVT) for AchoA aneurysms.

METHODS

The primary outcome of interest was angiographic and clinical outcomes. Secondary outcome variables transient and permanent ischemic complications, symptomatic choroidal artery occlusion and retreatment rates. 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 complication rates for Type 1(arterial type, directly arising from ICA) and Type 2(neck type, arising from AchoA branch)) AchoA aneurysms, ruptured vs non-ruptured and for flow diverter (FD) treatment versus coiling.

RESULTS

Our study included 10 studies with 416 patients with 430 AchoA aneurysms. The overall good clinical outcome rate (mRS score 0-2) is 94.5 % with a retreatment rate of 2.0 %. A subgroup analysis showed no statistical difference between coiling(75.3 %) and flow diverter(80.9 %) treatment in terms of complete occlusion(p-value:0.62). Overall permanent complication rate is 1.4 % (p-value:0.54) and transient ischemic complications rate is 4.2 %(p-value:0.61). Symptomatic choroidal artery occlusion rate is 0.8 %(p-value:0.51)Type 2 AchoA aneurysms had a significantly higher complication rate of 9.8 % (p-value<0.05) compared to Type 1 aneurysms. Unruptured aneurysms have significantly better clinical outcomes than ruptured aneurysms(OR: 0.11; [0.02;0.5], p-value:<0.05) CONCLUSION: Endovascular treatment of AchoA aneurysms demonstrated positive clinical results, with low rates of retreatment and complications. Coiling and flow diverters proved similar outcomes in achieving aneurysm occlusion. Ruptured aneurysms have lower good clinical outcomes comparing to unruptured aneurysms. Type 2 AchoA aneurysms had a higher risk of complications compared to Type 1.

Symptomatic non-stenotic carotid disease: current challenges and opportunities for diagnosis and treatment

Symptomatic non-stenotic carotid plaques (SyNC) are an under-researched and under-recognized source of stroke. Various imaging markers of non-stenotic carotid plaques that are associated with stroke risk have been identified, but these causal relationships need to be confirmed in additional prospective studies. Currently, there exists neither a standardized SyNC definition nor a dedicated set of imaging protocols, although researchers have started to address these shortcomings. Moreover, many neuroradiologists are still unaware of the condition, and hence do not comment on high-risk plaque features other than stenosis in their reports. Regarding SyNC treatment, scant data exist as to whether and to what extent medical, interventional and surgical treatments could influence the course of the disease; the relative lack of data on the 'natural' history of untreated SyNC makes treatment comparisons difficult. In our opinion, endovascular SyNC treatment represents the most promising treatment option for SyNC, since it allows for targeted elimination of the embolic source, with few systemic side effects and without the need for general anesthesia. However, currently available carotid devices are designed to treat stenotic lesions, and thus are not optimally designed for SyNC. Developing a device specifically tailored to SyNC could be an important step towards establishing endovascular SyNC treatment in clinical practice. In this review, we provide an overview of the current state of evidence with regard to epidemiological, clinical and imaging features of SyNC, propose a SyNC definition based on imaging and clinical features, and outline a possible pathway towards evidence-based SyNC therapies, with a special focus on endovascular SyNC treatment.

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.

Common Design, Data Elements and Core Outcome Measures Reported on Clinical Trials of Genicular Artery Embolization for Knee Osteoarthritis: An Interactive Systematic Review

RATIONALE AND OBJECTIVES

Genicular artery embolization (GAE) is an emerging, potentially effective treatment option in patients with knee osteoarthritis (OA). This study aimed to describe the current state of common design data elements (CDDEs) and core outcome measures (COMs) in recent trials of GAE for knee OA.

MATERIALS AND METHODS

A comprehensive search of seven online databases were searched within the Nested Knowledge AutoLit living review platform, followed by categorization of primary and secondary outcomes. Studies were tagged with the relevant outcomes of interest in each article. Results were synthesized and examined for the CDDEs.

RESULTS

Pain is the most frequent reported outcome, present in 23 of the 24 studies (95.8%). However, there is considerable variability in the description of in the study designs, procedural techniques, embolic materials, time points, and MRI parameters. Greater consistency is observed in eligibility criteria, and adverse events reporting. Although findings thus far have been favorable, current data is still constrained by the heterogeneity of the study design, embolization area nomenclature, limited follow-up, and in many cases, the absence of control group.

CONCLUSION

To enhance the potential for future meta-analyses and robust, evidence-based evaluations of GAE as a treatment for knee OA, further research is required to address the identified shortcomings. By establishing more standardized protocols, the efficacy and safety of GAE can be more accurately assessed and understood.

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.

Region-specific interobserver agreement of the Alberta Stroke Program Early Computed Tomography Score: A meta-analysis

BACKGROUND AND PURPOSE

The Alberta Stroke Program Early CT Score (ASPECTS) is a widely used scoring system for evaluating ischemic stroke to determine therapeutic strategy. However, there is variation in the interobserver agreement of ASPECTS. This systematic review and meta-analysis aimed to investigate the interobserver agreement of total and regional ASPECTS.

METHODS

A comprehensive search was conducted in the Web of Sciences, PubMed, and Scopus databases to identify relevant studies. Inclusion criteria were studies of noncontrast CT performed within 24 hours of ischemic stroke in the middle cerebral artery territory.

RESULTS

A total of 20 studies, with 3482 patients, reporting interobserver agreement of total and regional ASPECTS were included in the meta-analysis. The interobserver agreement for total ASPECTS in studies using Kappa coefficient (κ) analysis was substantial (κ = .67, 95% confidence interval [CI]: .57-.78). In studies using intraclass correlation coefficient (ICC) analysis, agreement was excellent (ICC = .84, 95% CI: .77-.90). Interobserver agreement was higher in studies in which the observer was unblinded to clinical scenario in both groups (κ = .74, 95% CI: .59-.89, and ICC = .82, 95% CI: .79-.85). Per-region analysis showed that the caudate nucleus had the highest agreement (κ = .68, 95% CI: .60-.76, and ICC = .84, 95% CI: .74-.93), while M2 and internal capsule in Kappa studies (κ = .45, 95% CI: .34-.55 and κ = .47, 95% CI: .28-.66), and M4 and internal capsule in ICC studies (ICC = .54, 95% CI: .43-.64 and ICC = .55, 95% CI: .18-.91) had the lowest agreement.

CONCLUSION

This meta-analysis demonstrates substantial to excellent interobserver agreement for total ASPECTS, which supports using this method for stroke treatment. However, findings emphasize the need to consider interobserver agreement in specific regions of ASPECTS for treatment decisions.

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.

Mortality Outcomes in a Large Population with and without Covert Cerebrovascular Disease

Covert cerebrovascular disease (CCD) is frequently reported on neuroimaging and associates with increased dementia and stroke risk. We aimed to determine how incidentally-discovered CCD during clinical neuroimaging in a large population associates with mortality. We screened CT and MRI reports of adults aged ≥50 in the Kaiser Permanente Southern California health system who underwent neuroimaging for a non-stroke clinical indication from 2009-2019. Natural language processing identified incidental covert brain infarcts (CBI) and/or white matter hyperintensities (WMH), grading WMH as mild/moderate/severe. Models adjusted for age, sex, ethnicity, multimorbidity, vascular risks, depression, exercise, and imaging modality. Of n=241,028, the mean age was 64.9 (SD=10.4); mean follow-up 4.46 years; 178,554 (74.1%) had CT; 62,474 (25.9%) had MRI; 11,328 (4.7%) had CBI; and 69,927 (29.0%) had WMH. The mortality rate per 1,000 person-years with CBI was 59.0 (95%CI 57.0-61.1); with WMH=46.5 (45.7-47.2); with neither=17.4 (17.1-17.7). In adjusted models, mortality risk associated with CBI was modified by age, e.g. HR 1.34 [1.21-1.48] at age 56.1 years vs HR 1.22 [1.17-1.28] at age 72 years. Mortality associated with WMH was modified by both age and imaging modality e.g., WMH on MRI at age 56.1 HR = 1.26 [1.18-1.35]; WMH on MRI at age 72 HR 1.15 [1.09-1.21]; WMH on CT at age 56.1 HR 1.41 [1.33-1.50]; WMH on CT at age 72 HR 1.28 [1.24-1.32], vs. patients without CBI or without WMH, respectively. Increasing WMH severity associated with higher mortality, e.g. mild WMH on MRI had adjusted HR=1.13 [1.06-1.20] while severe WMH on CT had HR=1.45 [1.33-1.59]. Incidentally-detected CBI and WMH on population-based clinical neuroimaging can predict higher mortality rates. We need treatments and healthcare planning for individuals with CCD.

Mechanical thrombectomy for the treatment of large vessel occlusion due to cancer-related cerebral embolism: A systematic review

BACKGROUND

Cancer-related cerebral embolism due to direct tumor embolization results in a rare acute ischemic stroke with large vessel occlusion (LVO). Despite the established status of mechanical thrombectomy (MT) in LVO management, its effectiveness and safety remains inadequately explored in this specific patient group.

METHODS

We conducted a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using the Nested Knowledge AutoLit software, encompassing databases like Embase, PubMed, Scopus, and Web of Science, from their inception up to 9 May 2023.

RESULTS

In the review of 35 studies encompassing 37 cases, mean patient age was 52 years, and 30% were female. Cardiac myxoma (29.7%), cardiac papillary fibroelastoma (16.2%), and squamous cell carcinoma of the lung (8.1%) were the most frequent underlying cancers. The left middle cerebral artery was the most commonly affected occlusion site (24.3%). Of the patients, 67.5% underwent MT alone, while 32.5% received MT combined with intravenous thrombolysis. Successful reperfusion (thrombolysis in cerebral infarction (TICI) 2b-3) was achieved in 89.1% of cases, with 59.4% reaching TICI 3. Functional independence was observed in 29.7% of patients.

CONCLUSION

While limitations exist, this comprehensive study highlights the potential benefits of MT in a patient group historically excluded from major trials, warranting further investigation.

Intensive vs Conventional Blood Pressure Control After Thrombectomy in Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Importance

Endovascular thrombectomy (EVT) is standard treatment for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO), but optimal post-EVT blood pressure (BP) control remains debated.

Objective

To assess the association of different systolic BP targets following EVT with functional outcomes, mortality, and complications in patients with AIS due to LVO.

Data Sources

Systematic review and meta-analysis of databases (PubMed, Embase, Web of Science, Scopus, and Cochrane Library) to September 8, 2023.

Study Selection

Inclusion criteria consisted of randomized clinical trials examining post-EVT management of systolic BP in patients with AIS and LVO comparing intensive vs conventional targets. Nonrandomized studies, observational studies, noninterventional trials, meeting abstracts, duplicate studies, studies with overlapping data, and non-English language studies were excluded. Two authors independently applied these criteria through a blinded review, with discrepancies resolved through consensus. The risk of bias in the included studies was assessed using the revised tool for assessing risk of bias in randomized trials.

Data Extraction and Synthesis

This study adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guideline. Three authors extracted data regarding study characteristics, baseline patient data, and outcomes of interest. The pooled data were analyzed using a random-effects meta-analysis.

Main Outcomes and Measures

Rates of functional independence, 90-day mortality, symptomatic intracranial hemorrhage, and hypotensive events.

Results

A total of 4 randomized clinical trials with 1571 initially enrolled patients were included in the analysis. Lower functional independence rates were observed in the intensive control group (relative risk [RR], 0.81 [95% CI, 0.67-0.98]). No significant differences were found in 90-day mortality (RR, 1.18 [95% CI, 0.92-1.52]), symptomatic intracranial hemorrhage (RR, 1.12 [95% CI, 0.75-1.67]), or hypotensive events (RR, 1.80 [95% CI, 0.37-8.76]). There was minimal heterogeneity among the studies included in the functional independence outcome (I2 = 13% and τ2 = 0.003), which was absent among other outcomes (I2 = 0 and τ2 = 0).

Conclusions and Relevance

These findings suggest that intensive post-EVT BP reduction does not yield benefits and may carry risks. While awaiting the results of additional ongoing trials, a conservative BP management strategy after endovascular recanalization is favored in daily practice.

Comparison of Balloon Guide Catheters and Standard Guide Catheters for Acute Ischemic Stroke: An Updated Systematic Review and Meta-analysis

OBJECTIVE

The objective of this study was to update our 2021 systematic review and meta-analysis which reported that balloon guide catheters (BGC) are associated with superior clinical and angiographic outcomes compared to standard guide catheters for treatment of acute ischemic stroke.

METHODS

We conducted a systematic review of 7 electronic databases to identify literature published between January 2010 and September 2023 reporting BGC versus non-BGC approaches. Primary outcomes were final modified thrombolysis in cerebral infarction (mTICI) ≥2b, first-pass effect (mTICI ≥2c on first pass), and modified Rankin scale 0-2 at 90 days. The risk of bias was assessed using the Newcastle Ottawa Scale. A separate random effects model was fitted for each outcome. Subgroup analyses by first-line approach were conducted.

RESULTS

Twenty-four studies comprising 8583 patients were included (4948 BGC; 3635 non-BGC; 1561 BGC + Stent-retriever; 1297 non-BGC + Stent-retriever). Nine studies had low risk of bias, 3 were moderate risk, and 12 were high risk. Patients treated with BGCs had higher odds of achieving mTICI 2b/3, first-pass effect mTICI 2c/3, and modified Rankin scale 0-2 at 90 days (P < 0.001). The number of patients needed to treat in order to achieve one additional successful recanalization is 17. BGC + Stent-retriever was associated with higher odds of mTICI≥2b, 90-day modified Rankin scale 0-2, and reduced odds of 90-day mortality compared to non-BGC + Stent-retrievers. The main limitation was the absence of randomized trials.

CONCLUSIONS

These findings corroborate our previous results suggesting that MT using BGCs is associated with better safety and effectiveness outcomes for acute ischemic stroke, especially BGC + Stent-retrievers.

Net water uptake as a predictive neuroimaging marker for acute ischemic stroke outcomes: a meta-analysis

OBJECTIVE

To assess the role of net water uptake (NWU) in predicting outcomes in acute ischemic stroke (AIS) patients.

METHODS

A systematic review and meta-analysis were performed, adhering to established guidelines. The search covered PubMed, Scopus, Web of Science, and Embase databases until July 1, 2023. Eligible studies reporting quantitative ischemic lesion NWU in admission CT scans of AIS patients, stratified based on outcomes, were included. Data analysis was performed using R software version 4.2.1.

RESULTS

Incorporating 17 original studies with 2217 AIS patients, NWU was significantly higher in patients with poor outcomes compared to those with good outcomes (difference of medians: 5.06, 95% CI: 3.00-7.13, p < 0.001). Despite excluding one outlier study, considerable heterogeneity persisted among the included studies (I2 = 90.8%). The meta-regression and subgroup meta-analyses demonstrated significantly higher NWU in patients with poor functional outcome, as assessed by modified Rankin Scale (difference of medians: 3.83, 95% CI: 1.98-5.68, p < 0.001, I2 = 72.9%), malignant edema/infarct (difference of medians: 8.30, 95% CI: 4.01-12.58, p < 0.001, I2 = 95.6%), and intracranial hemorrhage (difference of medians: 5.43, 95% CI: 0.44-10.43, p = 0.03, I2 = 91.1%).

CONCLUSION

NWU on admission CT scans shows promise as a predictive marker for outcomes in AIS patients. Prospective, multicenter trials with standardized, automated NWU measurement are crucial for robustly predicting diverse clinical outcomes.

CLINICAL RELEVANCE STATEMENT

The potential of net water uptake as a biomarker for predicting outcomes in acute ischemic stroke patients holds significant promise. Further validation through additional research could lead to its integration into clinical practice, potentially improving the accuracy of clinical decision-making and allowing for the development of more precise patient care strategies.

KEY POINTS

• Net water uptake, a CT-based biomarker, quantifies early brain edema after acute ischemic stroke. • Net water uptake is significantly higher in poor outcome acute ischemic stroke patients. • Net water uptake on CT scans holds promise in predicting diverse acute ischemic stroke outcomes.

Safety and efficacy of the Woven Endo-Bridge-17 device for intracranial aneurysm treatment: A systematic review and meta-analysis

BACKGROUND

The Woven Endo-Bridge (WEB) device revolutionized the treatment of wide-necked bifurcation aneurysms by intrasaccular flow diversion. The latest advancement is the WEB-17 system, offering greater flexibility with fewer wires, enabling treatment of smaller distal aneurysms using smaller microcatheters than the WEB-21 system.

METHODS

We conducted a systematic review following preferred reporting items for systematic reviews and meta-analyses guidelines, analyzing data from seven retrospective cohort studies involving 483 aneurysms treated with the WEB-17 device. Statistical analysis computed pooled prevalence rates and 95% confidence intervals using appropriate models for each outcome and R software version 4.3.1 (R Foundation for Statistical Computing, Vienna, Austria).

RESULTS

Technical success was achieved in 475 out of 483 aneurysms treated with the WEB-17 device, with a success rate of 98.34% (95% confidence interval (CI) = 96.72-99.17). Among the successful cases, 4.97% (95% CI = 1.60-14.39) required adjunctive devices. Adequate occlusion, defined as complete occlusion or neck remnants, was observed in 94.41% (95% CI = 88.17-97.46) of cases. Periprocedural complications were infrequent, with thromboembolic complications occurring in 4.93% (95% CI = 3.29-7.30) of cases, hemorrhagic complications in 1.28% (95% CI = 0.58-2.83), and postprocedural neurologic complications in 0.99% (95% CI = 0.31-3.14). Procedure-related morbidity was observed in 1.71% (95% CI = 0.86-3.39) of cases, and there was one procedure-related mortality reported at 0.21% (95% CI = .03-1.50). Mortality unrelated to the procedure occurred in 1% (95% CI = 0.23-4.15).

CONCLUSION

Our findings suggest that the WEB-17 device is associated with a high rate of technical success, favorable angiographic outcomes, and a low rate of periprocedural complications. Further research, including prospective trials, is needed to confirm these findings and establish its safety and efficacy definitively.

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.

National Institutes of Health grant funding for cerebrovascular diseases

BACKGROUND

Federal research funding is highly sought after but may be challenging to attain. A clear understanding of funding for specific diseases, such as cerebrovascular disorders, might help researchers regarding which National Institutes of Health (NIH) institutes fund research into specific disorders and grant types.

OBJECTIVE

To examine the current scope of NIH grant funding for cerebrovascular conditions.

METHODS

The NIH-developed RePORTER was used to extract active NIH-funded studies related to cerebrovascular diseases through January 2023. Duplicate studies were removed, and projects were manually screened and labeled in subcategories as clinical and basic science and as research subcategories. Extracted data included total funding, grant types, institutions that received funding, and diseases studied. Python (version 3.9) and SciPy library were used for statistical analyses.

RESULTS

We identified 1232 cerebrovascular projects across seven diseases with US$699 952 926 in total funding. The cerebrovascular diseases with the greatest number of grants were ischemic stroke (705, or 57.2% of all funded projects), carotid disease (193, or 15.7%), and hemorrhagic stroke (163, or 13.2%). R01 grants were the most common mechanism of funding (632 grants, or 51.3%). The National Institute of Neurological Disorders and Stroke (NINDS) funded the most projects (504 projects; US$325 536 405), followed by the National Heart, Lung, and Blood Institute (NHLBI) (376 projects; US$216 784 546).

CONCLUSION

Cerebrovascular disease receives roughly US$700 million in NIH funding. Ischemic stroke accounts for the majority of NIH-funded cerebrovascular projects, and R01 grants are the most common funding mechanism. Notably, NHLBI provides a large proportion of funding, in addition to NINDS.

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.

Flow diverters in the treatment of intracranial dissecting aneurysms: a systematic review and meta-analysis of safety and efficacy

BACKGROUND

Intracranial dissecting aneurysms present clinical challenges, demanding immediate intervention due to their high bleeding risk. While traditional treatments have limitations, the potential of flow diverters shows promise but remains a subject of ongoing debate for optimal management. The aim of this study was assess the safety and efficacy of flow diverters in the treatment of intracranial dissecting aneurysms.

METHODS

A systematic review and meta-analysis was performed following established guidelines. The search encompassed PubMed, Scopus, Web of Science, and Embase databases up to July 20, 2023. Eligible studies reporting outcomes of interest were included, and relevant data were extracted and analyzed using R software.

RESULTS

The analysis, based on data pooled from 20 included studies involving 329 patients, revealed a favorable functional outcome rate of 89.7% at the last follow-up. The mortality rate during the follow-up period was 2.4%, decreasing to 0.9% when excluding the outlier study. In the final angiographic follow-up, a complete occlusion rate of 71.7% and an adequate occlusion rate of 88.3% were observed. Notably, studies with longer angiographic follow-up times exhibited lower rates of complete (P=0.02) and adequate (P<0.01) occlusion. A minimal aneurysm recurrence/rebleeding rate of 0.1% was noted, while in-stent stenosis/thrombosis occurred at a rate of 1.14%. Additionally, ischemic events/infarctions were seen in 3.3% of cases. The need for retreatment was minimal, with a rate of 0.9%, and the technical success rate was impressively high at 99.1%.

CONCLUSION

This study highlights the safety and efficacy of flow diverters in treating intracranial dissecting aneurysms. Further research, encompassing larger multicenter studies with extended follow-up periods, is crucial for comprehending occlusion dynamics, refining treatment strategies, improving long-term outcomes, and addressing methodological limitations.

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.

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.

Effect of Treatment Choice on Short-Term and Long-Term Outcomes for Carotid Near-Occlusion: A Meta-Analysis

OBJECTIVE

Current guidelines recommend best medical treatment (BMT) over revascularization for carotid near-occlusion (CNO); however, it remains unclear whether BMT, carotid artery stenting (CAS), or carotid endarterectomy (CEA) is the optimal treatment strategy. The present meta-analysis aimed to compare outcomes among patients with CNO receiving BMT, CAS, or CEA.

METHODS

PubMed, Web of Science, Scopus, and Embase were searched. English studies with ≥1 month follow-up, that used established CNO diagnostic guidelines, that provided outcomes by treatment, and in which 95% confidence intervals (CIs) were calculable were included. Studies on acute ischemic stroke (AIS) requiring emergent reperfusion therapy, nonatherosclerotic lesions, nonprimary research articles, non-English, and nonhuman studies were excluded. Outcomes were mortality, AIS, transient ischemic attack, myocardial infarction within and beyond 30 days, and restenosis. A generalized linear mixed model, subgroup analysis, and meta-regression were used to compare outcomes.

RESULTS

Thirty-eight studies were included. Pooled rates for AIS beyond 30 days were 9.90% (95% CI, 4.31%-21.16%), 0.79% (95% CI, 0.24%-2.53%), and 0.80% (95% CI, 0.15%-4.07%) for BMT, CAS, and CEA, respectively. Subgroup analysis was statistically significant (P < 0.001). Meta-regression showed lower incidence favoring procedural intervention (CAS vs. BMT, P = 0.001; CEA vs. BMT, P = 0.003). Subgroup analysis for mortality beyond 30 days was also significant (P = 0.016) but meta-regression did not favor one treatment over another. Other outcomes were not statistically significant.

CONCLUSIONS

Revascularization for CNO may decrease long-term stroke rates. Given that current guidelines are based on randomized controlled trials from the 1990s, updated randomized trials are warranted to determine the optimal treatment for CNO.

Machine learning prediction of hospital discharge disposition for inpatients with acute ischemic stroke following mechanical thrombectomy in the United States

BACKGROUND AND PURPOSE

Predicting patient recovery and discharge disposition following mechanical thrombectomy remains a challenge in patients with ischemic stroke. Machine learning offers a promising prognostication approach assisting in personalized post-thrombectomy care plans and resource allocation. As a large national database, National Inpatient Sample (NIS), contain valuable insights amenable to data-mining. The study aimed to develop and evaluate ML models predicting hospital discharge disposition with a focus on demographic, socioeconomic and hospital characteristics.

MATERIALS AND METHODS

The NIS dataset (2006-2019) was used, including 4956 patients diagnosed with ischemic stroke who underwent thrombectomy. Demographics, hospital characteristics, and Elixhauser comorbidity indices were recorded. Feature extraction, processing, and selection were performed using Python, with Maximum Relevance - Minimum Redundancy (MRMR) applied for dimensionality reduction. ML models were developed and benchmarked prior to interpretation of the best model using Shapley Additive exPlanations (SHAP).

RESULTS

The multilayer perceptron model outperformed others and achieved an AUROC of 0.81, accuracy of 77 %, F1-score of 0.48, precision of 0.64, and recall of 0.54. SHAP analysis identified the most important features for predicting discharge disposition as dysphagia and dysarthria, NIHSS, age, primary payer (Medicare), cerebral edema, fluid and electrolyte disorders, complicated hypertension, primary payer (private insurance), intracranial hemorrhage, and thrombectomy alone.

CONCLUSION

Machine learning modeling of NIS database shows potential in predicting hospital discharge disposition for inpatients with acute ischemic stroke following mechanical thrombectomy in the NIS database. Insights gained from SHAP interpretation can inform targeted interventions and care plans, ultimately enhancing patient outcomes and resource allocation.

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.

Endovascular thrombectomy after acute ischemic stroke of the basilar artery: a meta-analysis of four randomized controlled trials

BACKGROUND

Previous randomized controlled trials (RCTs) and meta-analyses were underpowered to demonstrate the superiority of endovascular thrombectomy (EVT) over medical therapy (MEDT) in the treatment of acute ischemic stroke due to large vessel occlusion of the posterior circulation (PC-LVO). We performed an updated systematic review and meta-analysis after the publication of the BAOCHE and ATTENTION trials to determine whether EVT can benefit patients presenting with PC-LVO.

METHODS

Using Nested Knowledge, we screened literature for RCTs on EVT in PC-LVO. The primary outcome was 90-day modified Rankin Scale (mRS) score 0-3, and secondary outcomes included 90-day mRS score 0-2, 90-day mortality, and rate of symptomatic intracranial hemorrhage (sICH). A random-effects model was used to compute rate ratios (RRs) and their corresponding 95% confidence intervals (CIs).

RESULTS

Four RCTs with 988 patients, 556 patients in the EVT arm and 432 patients in the MEDT arm, were included in the meta-analysis. EVT resulted in significantly higher rates of mRS score 0-3 (RR=1.54; 95% CI 1.16 to 2.04; P=0.002) and functional independence (RR=1.83; 95% CI 1.08 to 3.08; P=0.024), and lower rates of mortality (RR=0.76; 95% CI 0.65 to 0.90; P=0.002) at 90-day follow-up compared with MEDT alone. However, EVT patients had higher rates of sICH (RR=7.48; 95% CI 2.27 to 24.61; P<0.001).

CONCLUSIONS

EVT conferred significant patient benefit over MEDT alone in the treatment of PC-LVO. Future studies should better define patients for whom EVT is futile and determine factors that contribute to higher rates of sICH.

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.

Gender disparities in industry compensation and research payments among neurointerventional surgeons in the USA

BACKGROUND

The purpose of this study is to examine the presence of gender disparity represented by industry payments and research funding within the field of interventional neuroradiology.

METHODS

Payment information was collected using the Centers for Medicare and Medicaid Services Open Payment database for the year 2019. Kruskal-Wallis tests were used to analyze differences in annual compensation based on sex in $US, while controlling for geographic factors, academic rank, and h-index. A sample t-test was performed to look at gender differences in h-indexes.

RESULTS

The study cohort was comprised of 893 interventional neuroradiologists, 73 (8.2%) of which were female. Of the $48889.20 in mean annual payments reported in the database, $5847.13 (11.2%) went to female interventional neuroradiologists (P<0.05). The significant difference in compensation between male and female neuroradiologists was evident after controlling for state-level variance and academic position. There was a statistically significant difference in total reimbursement (P<0.001), research (P<0.001), consulting (P<0.04), food and beverage (P<0.02), and compensation for services other than consulting between males and females (P<0.02). A statistically significant difference was found for h-index based on gender (males=16.7, females=10.1; P<0.001).

CONCLUSIONS

Our findings indicate that in the field of interventional neuroradiology, females receive less research funding and private industry compensation, have lower h-indexes, and are less likely to occupy the highest academic positions. The difference in funding did not differ when accounting for geographic state of practice and academic rank. Future studies should work to identify potential contributory factors of these trends.

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.

Acute Adverse Events After Iodinated Contrast Agent Administration of 359,977 Injections: A Single-Center Retrospective Study

OBJECTIVE

To assess the effects of patient variables, examination variables, and seasonality on allergic-like and physiologic reactions to iodinated contrast material (ICM).

PATIENTS AND METHODS

All ICM-enhanced computed tomography (CT) examinations performed from June 1, 2009, to May 9, 2017, at our institution were included. Reactions were identified and categorized as allergic-like or physiologic and mild, moderate, or severe. The effect of patient and examination variables on reactions was evaluated by logistic regression models.

RESULTS

A total of 359,977 CT examinations performed on 176,886 unique patients were included. A total of 1150 allergic-like reactions (0.32%; 19 severe [0.005%]) and 679 physiologic reactions (0.19%; 3 severe [0.0008%]) occurred. On multivariable analysis, iopromide had higher rates of reactions compared with iohexol (allergic-like reactions: odds ratio [OR], 3.07 [95% CI, 2.37 to 3.98], P<.0001; physiologic reactions: OR, 2.60 [1.92 to 3.52], P<.0001). Non-White patients had higher rates of reactions compared with White patients (allergic-like reactions: OR, 1.77 [1.36-2.30], P<.0001; physiologic reactions: OR, 1.76 [1.27-2.42], P=.0006). Patient age, sex, prior ICM reaction, ICM dose, CT location, and CT type were also significantly associated with reactions. No significant seasonality trend was observed (P=.07 and .80).

CONCLUSION

Non-White patients and patients administered iopromide had higher rates of acute reactions compared with White patients and patients administered iohexol. Younger patients (<50 years vs 51 to 60 years), female sex, history of ICM allergy or other allergies, ICM dose, and contrast-enhanced CT location and type also correlated with higher acute reaction rates.

Stratifying future stroke risk with incidentally-discovered white matter disease severity and covert brain infarct site

BACKGROUND

Covert cerebrovascular disease (CCD) includes white matter disease (WMD) and covert brain infarction (CBI). Incidentally-discovered CCD is associated with increased risk of subsequent symptomatic stroke. However, it is unknown whether the severity of WMD or the location of CBI predicts risk.

OBJECTIVES

To examine the association of incidentally-discovered WMD severity and CBI location with risk of subsequent symptomatic stroke.

METHOD

This retrospective cohort study includes patients 50 years old in the Kaiser Permanente Southern California health system who received neuroimaging for a non-stroke indication between 2009-2019. Incidental CBI and WMD were identified via natural language processing of the neuroimage report, and WMD severity was classified into grades.

RESULTS

261,960 patients received neuroimaging; 78,555 (30.0%) were identified to have incidental WMD, and 12,857 (4.9%) to have incidental CBI. Increasing WMD severity is associated with increased incidence rate of future stroke. However, the stroke incidence rate in CT-identified WMD is higher at each level of severity compared to rates in MRI-identified WMD. Patients with mild WMD via CT have a stroke incidence rate of 24.9 per 1,000 person-years, similar to that of patients with severe WMD via MRI. Among incidentally-discovered CBI patients with a determined CBI location, 97.9% are subcortical rather than cortical infarcts. CBI confers a similar risk of future stroke, whether cortical or subcortical, or whether MRI- or CT-detected.

CONCLUSIONS

Increasing severity of incidental WMD is associated with an increased risk of future symptomatic stroke, dependent on the imaging modality. Subcortical and cortical CBI conferred similar risks.

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.

Off-Label Use of the 8-F Angio-Seal for Closure of Greater than 8-F Common Femoral Arterial Access: A Systematic Review and Meta-Analysis

PURPOSE

To evaluate the safety of >8-F access closures using 8-F Angio-Seal.

MATERIALS AND METHODS

An electronic search was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines using Web of Science, Embase, Scopus, and PubMed databases from inception until January 17, 2022. Actionable and nonactionable bleeding events were defined in conjugation with the Bleeding Academic Research Consortium definition. Prevalence rates with corresponding 95% CIs were calculated using R software version 4.2.2. Eight articles, with 422 patients, were included in the analysis.

RESULTS

The overall groin adverse event rate was 5.92% (95% CI, 3.01-11.34). The most commonly reported adverse events were any bleeding (5.74%; 95% CI, 3.23-10.00) (nonactionable bleeding, 0.96% [95% CI, 0.10-8.30]; actionable bleeding, 2.30% [95% CI, 0.89-5.84]), pseudoaneurysm (1.18%; 95% CI, 0.49-2.81), and groin hematoma (1.28%; 95% CI, 0.23-6.79). The least commonly reported adverse events were device failure and vessel occlusion/stenosis, with rates 0.29% (95% CI, 0.01-7.41) and 0.45% (95% CI, 0.02-7.74), respectively. No studies recorded events regarding the following adverse events: mortality, infection, deep venous thrombosis, and retroperitoneal hematoma. Moreover, the results showed significant differences, based on the sheath size used, in actionable bleeding (P = .04) and the rate of need for surgical repair (P < .01).

CONCLUSIONS

Common femoral artery access of >8-F can be effectively closed with the Angio-Seal with comparable outcomes to those of <8 F; however, larger access approaching 14 F is associated with a significant increase in morbidity. Further safety is needed, especially for the larger access sizes.