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.

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.

Hypoperfusion intensity ratio as a predictor of outcomes after thrombectomy triage: A call for data homogeneity.

BACKGROUND: Collateral blood flow markers have been associated with outcomes after thrombectomy in patients presenting with acute ischemic stroke due to large vessel occlusion (AIS-LVO). Hypoperfusion intensity ratio (HIR), a metric reflecting tissue level collaterals, is one such marker with the potential to delineate patients who do and do not do well after thrombectomy. We determined if HIR correlated with successful reperfusion after thrombectomy. METHODS: Using Nested Knowledge, we screened literature for studies comparing patients with favorable versus unfavorable HIR, distinguished by a cutoff of 0.4, who underwent thrombectomy triage. The primary outcome was reperfusion success, as measured by thrombolysis in cerebral infarction ≥2b and secondary outcomes included rate of symptomatic intracranial hemorrhage, mortality at 90 days, and modified Rankin scale scores 0-2 at 90 days. A random effects model was used to compute pooled prevalence rates and their corresponding 95% confidence intervals (CI). RESULTS: Three studies with 973 patients, 496 with favorable HIR, and 477 with unfavorable HIR were included in this meta-analysis. The odds of reperfusion success were not significantly different between patients who had favorable versus unfavorable HIR (OR 0.96, 95% CI: 0.31-3.04) across two of the studies. Analysis of the remaining outcome variables was precluded by significant heterogeneity in data element reporting. CONCLUSIONS: This meta-analysis was considerably limited by heterogeneity. Future meta-analyses on this topic, and other topics in the field of neurointervention would benefit from improved harmonization of study design and data element reporting.

Predictors of aneurysm occlusion after treatment with flow diverters: a systematic literature review.

BACKGROUND: Flow diverters (FDs) have become an integral part of treatment for brain aneurysms. AIM: To summarize available evidence of factors associated with aneurysm occlusion (AO) after treatment with a FD. METHODS: References were identified using the Nested Knowledge AutoLit semi-automated review platform between January 1, 2008 and August 26, 2022. The review focuses on preprocedural and postprocedural factors associated with AO identified in logistic regression analysis. Studies were included if they met the inclusion criteria of study details (ie, study design, sample size, location, (pre)treatment aneurysm details). Evidence levels were classified by variability and significancy across studies (eg, low variability ≥5 studies and significance in ≥60% throughout reports). RESULTS: Overall, 2.03% (95% CI 1.22 to 2.82; 24/1184) of screened studies met the inclusion criteria for predictors of AO based on logistic regression analysis. Predictors of AO with low variability in multivariable logistic regression analysis included aneurysm characteristics (aneurysm diameter), particularly complexity (absence of branch involvement) and younger patient age. Predictors of moderate evidence for AO included aneurysm characteristics (neck width), patient characteristics (absence of hypertension), procedural (adjunctive coiling) and post-deployment variables (longer follow-up; direct postprocedural satisfactory occlusion). Variables with a high variability in predicting AO following FD treatment were gender, FD as re-treatment strategy, and aneurysm morphology (eg, fusiform or blister). CONCLUSION: Evidence of predictors for AO after FD treatment is sparse. Current literature suggests that absence of branch involvement, younger age, and aneurysm diameter have the highest impact on AO following FD treatment. Large studies investigating high-quality data with well-defined inclusion criteria are needed for greater insight into FD effectiveness.

MASTRO I: Meta-Analysis and Systematic Review of thrombectomy stent retriever outcomes: comparing functional, safety and recanalization outcomes between EmboTrap, Solitaire and Trevo in acute ischemic stroke.

Aim: Stent-retriever (SR) thrombectomy has demonstrated superior outcomes in patients with acute ischemic stroke compared with medical management alone, but differences among SRs remain unexplored. We conducted a Systematic Review/Meta-Analysis to compare outcomes between three SRs: EmboTrap®, Solitaire™, and Trevo®. Methods: We conducted a PRISMA-compliant Systematic Review among English-language studies published after 2014 in PubMed/MEDLINE that reported SRs in ≥25 patients. Functional and safety outcomes included 90-day modified Rankin scale (mRS 0-2), mortality, symptomatic intracranial hemorrhage (sICH), and embolization to new territory (ENT). Recanalization outcomes included modified thrombolysis in cerebral infarction (mTICI) and first-pass recanalization (FPR). We used a random effects Meta-Analysis to compare outcomes; subgroup and outlier-influencer analysis were performed to explore heterogeneity. Results: Fifty-one articles comprising 9,804 patients were included. EmboTrap had statistically significantly higher rates of mRS 0-2 (57.4%) compared with Trevo (50.0%, p = 0.013) and Solitaire (45.3%, p < 0.001). Compared with Solitaire (20.4%), EmboTrap (11.2%, p < 0.001) and Trevo (14.5%, p = 0.018) had statistically significantly lower mortality. Compared with Solitaire (7.7%), EmboTrap (3.9%, p = 0.028) and Trevo (4.6%, p = 0.049) had statistically significantly lower rates of sICH. There were no significant differences in ENT rates across all three devices (6.0% for EmboTrap, 5.3% for Trevo, and 7.7% for Solitaire, p = 0.518). EmboTrap had numerically higher rates of recanalization; however, no statistically significant differences were found. Conclusion: The results of our Systematic Review/Meta-Analysis suggest that EmboTrap may be associated with significantly improved functional outcomes compared with Solitaire and Trevo. EmboTrap and Trevo may be associated with significantly lower rates of sICH and mortality compared with Solitaire. No significant differences in recanalization and ENT rates were found. These conclusions are tempered by limitations of the analysis including variations in thrombectomy techniques in the field, highlighting the need for multi-arm RCT studies comparing different SR devices to confirm our findings.

The diagnostic performance of artificial intelligence algorithms for identifying M2 segment middle cerebral artery occlusions: A systematic review and meta-analysis.

BACKGROUND: Artificial intelligence (AI)-based algorithms have been developed to facilitate rapid and accurate computed tomography angiography (CTA) assessment in proximal large vessel occlusion (LVO) acute ischemic stroke, including internal carotid artery and M1 occlusions. In clinical practice, however, the detection of medium vessel occlusion (MeVO) represents an ongoing diagnostic challenge in which the added value of AI remains unclear. PURPOSE: To assess the diagnostic performance of AI platforms for detecting M2 occlusions. METHODS: Studies that report the diagnostic performance of AI-based detection of M2 occlusions were screened, and sensitivity and specificity data were extracted using the semi-automated AutoLit software (Nested Knowledge, MN) platform. STATA (version 16 IC; Stata Corporation, College Station, Texas, USA) was used to conduct all analyses. RESULTS: Eight studies with a low risk of bias and significant heterogeneity were included in the quantitative and qualitative synthesis. The pooled estimates of sensitivity and specificity of AI platforms for M2 occlusion detection were 64% (95% CI, 53 to 74%) and 97% (95% CI, 84 to 100%), respectively. The area under the curve (AUC) in the SROC curve was 0.79 (95% CI, 0.74 to 0.83). CONCLUSION: The current performance of the AI-based algorithm makes it more suitable as an adjunctive confirmatory tool rather than as an independent one for M2 occlusions. With the rapid development of such algorithms, it is anticipated that newer generations will likely perform much better.

Mortality of COVID-19 in patients with hematological malignancies versus solid tumors: a systematic literature review and meta-analysis.

Cancer patients are more vulnerable to COVID-19 compared to the general population, but it remains unclear which types of cancer have the highest risk of COVID-19-related mortality. This study examines mortality rates for those with hematological malignancies (Hem) versus solid tumors (Tumor). PubMed and Embase were systematically searched for relevant articles using Nested Knowledge software (Nested Knowledge, St Paul, MN). Articles were eligible for inclusion if they reported mortality for Hem or Tumor patients with COVID-19. Articles were excluded if they were not published in English, non-clinical studies, had insufficient population/outcomes reporting, or were irrelevant. Baseline characteristics collected included age, sex, and comorbidities. Primary outcomes were all-cause and COVID-19-related in-hospital mortality. Secondary outcomes included rates of invasive mechanical ventilation (IMV) and intensive care unit (ICU) admission. Effect sizes from each study were computed as logarithmically transformed odds ratios (ORs) with random-effects, Mantel-Haenszel weighting. The between-study variance component of random-effects models was computed using restricted effects maximum likelihood estimation, and 95% confidence intervals (CIs) around pooled effect sizes were calculated using Hartung-Knapp adjustments. In total, 12,057 patients were included in the analysis, with 2,714 (22.5%) patients in the Hem group and 9,343 (77.5%) patients in the Tumor group. The overall unadjusted odds of all-cause mortality were 1.64 times higher in the Hem group compared to the Tumor group (95% CI: 1.30-2.09). This finding was consistent with multivariable models presented in moderate- and high-quality cohort studies, suggestive of a causal effect of cancer type on in-hospital mortality. Additionally, the Hem group had increased odds of COVID-19-related mortality compared to the Tumor group (OR = 1.86 [95% CI: 1.38-2.49]). There was no significant difference in odds of IMV or ICU admission between cancer groups (OR = 1.13 [95% CI: 0.64-2.00] and OR = 1.59 [95% CI: 0.95-2.66], respectively). Cancer is a serious comorbidity associated with severe outcomes in COVID-19 patients, with especially alarming mortality rates in patients with hematological malignancies, which are typically higher compared to patients with solid tumors. A meta-analysis of individual patient data is needed to better assess the impact of specific cancer types on patient outcomes and to identify optimal treatment strategies.

Comparing Tigertriever 13 to other thrombectomy devices for distal medium vessel occlusion: A systematic review and meta-analysis.

BACKGROUND: There is limited evidence on the optimal endovascular strategy for treatment of distal medium-vessel occlusions (DMVO). The low-profile Tigertriever 13 stent-triever shows early promise as an adaptable device that can navigate the distal vasculature without increasing complication risk in DMVO. METHODS: Using Nested Knowledge, we screened literature for RCTs and cohort studies on the endovascular treatment of DMVO. The primary outcome was reperfusion success, as measured by thrombolysis in cerebral infarction (TICI) ≥ 2b and secondary outcomes included rate of symptomatic intracranial hemorrhage (sICH), mortality at 90 days, and modified Rankin scale (mRS) scores 0-2 at 90 days. A random-effects model was used to compute pooled prevalence rates and their corresponding 95% confidence intervals (CI). RESULTS: Eleven studies with 1402 patients, 167 patients treated by Tigertriever 13 and 1235 patients treated by other devices, were included in the meta-analysis. The rate of reperfusion success was similar in patients treated by Tigertriever 13 (83.2% [95% CI: 71.5-96.7%]) versus other devices (81.6% [95% CI: 75.3-88.4%], p > 0.05). The rate of sICH was also similar in patients treated by Tigertriever 13 (7.2% [95% CI: 4.1-12.5%]) versus other devices (6.9% [95% CI: 5.5-8.8%]). There was significant heterogeneity in the reporting of mortality and mRS. CONCLUSIONS: Tigertriever 13 had similar rates of reperfusion success and sICH as other devices used for the treatment of DMVO. Heterogeneity in data element reporting prevented further analyses. Further studies evaluating Tigertriever 13 and other potential devices in DMVO should attempt to harmonize data element reporting.

Contralateral approach for the treatment of a distal supraclinoid aneurysm: a technical case report.

BACKGROUND: When treating intracranial aneurysms with open microsurgery, rare cases arise in which an ipsilateral approach leads to poor visualization, lack of proximal control, or potential damage to nearby vital structures due to the anatomy of the aneurysm. CASE DESCRIPTION: We describe a patient with a small, unruptured aneurysm arising from the medial aspect of the distal supraclinoid internal carotid artery (ICA), just below the ICA bifurcation. A contralateral surgical approach was chosen because our view of the aneurysm from an ipsilateral approach would have been obstructed by the ICA. The contralateral approach provided excellent exposure of the aneurysm and allowed for precise clip placement without complications. CONCLUSIONS: Contralateral approaches may be a good option for some small medially pointing aneurysm of large proximal cerebral arteries.

Technical note: the use of frameless stereotactic guidance in the treatment of peripheral intracranial aneurysms.

Frameless stereotactic guidance (FSG) has previously been reported to have advantages over intraoperative computed tomography (CT) and frame-based imaging guidance methods in the targeting of intracranial lesions. We report our experience using FSG to minimize brain dissection during microsurgical repair of peripheral aneurysms. We used FSG as a surgical adjunct in the management of 91 peripheral aneurysms. It was used to localise and avoid larger bridging veins, enabling us to minimise unnecessary brain dissection by coming directly down on the aneurysm dome in unruptured lesions or targeting the parent artery just proximal to the aneurysm in ruptured cases. We treated 72 aneurysms located on the distal ACA (79%), 7 on the PCA (7.7%), 6 on the MCA distal to the MCA bifurcation (6.6%), and 6 on the SCA (6.6%). There were no complications related to FSG use. However, we noted a tendency to create an overly limited corridor to the aneurysm, which did not allow sufficient proximal or distal control of the parent artery. In these cases, we had to widen our exposure by further opening the interhemispheric fissure to obtain more proximal control once the aneurysm was reached. Subsequently, we learned to avoid this problem by creating a slightly wider corridor during the initial exposure. Using FSG as a surgical adjunct for peripheral intracranial aneurysms allowed us to safely limit craniotomy size and brain dissection while more confidently exposing these unusually situated lesions, facilitating aneurysm clipping in our series.

Aspiration thrombectomy versus stent retriever thrombectomy alone for acute ischemic stroke: evaluating the overlapping meta-analyses.

BACKGROUND: Previous studies comparing a direct aspiration first pass technique (ADAPT) and stent retrievers have inconsistent methodologies and data reporting, limiting the ability to accurately assimilate data from different studies that would inform treatment of acute ischemic stroke (AIS) treatment. OBJECTIVE: To conduct a systematic review to discuss and compare the findings of all relevant meta-analysis studies comparing the efficacy of the ADAPT and stent retriever techniques. METHODS: The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), where meta-analyses comparing the efficacy of the ADAPT technique and stent retrievers in the treatment of AIS were included. We extracted all relevant data from the included studies and assessed the quality of the included meta-analyses using the Assessment of Multiple Systematic Review (AMSTAR-2). RESULTS: Seven relevant studies met our inclusion criteria and were suitable for the qualitative synthesis. All included studies obtained data from randomized controlled trials (RCTs) and observational investigations (including levels II, III, and IV). At the same time, none of them used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) for quality assessment. In accordance with AMSTAR-2, two studies were rated 'high', while the other five were rated 'moderate'. CONCLUSIONS: Present evidence is insufficient to clarify the superiority of one modality over the other. Further RCTs on this comparison must be conducted prior to designing further meta-analyses or making conclusive interpretations. Procedure duration and cost should be taken into consideration for any future studies.

Common Data Elements Analysis of Mechanical Thrombectomy Clinical Trials for Acute Ischemic Stroke with Large Core Infarct.

BACKGROUND: Clinical trials addressing large core acute ischemic stroke (AIS) are ongoing across 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 studies. This common data element study aims to provide an overview of 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 trials. RESULTS: The most reported data element was ASPECTS score but with varied definitions of what constitutes 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 3­month mark. Additionally, the TENSION trial reported the frequency of serious adverse events, including mortality, at the 1­week and 12-month mark. DISCUSSION: Overall, in large core trials there is a large degree of heterogeneity in the collected data elements. Differences in definition and timepoints render reaching a unified standard difficult, which hinders high quality meta-analyses and cohesive evidence-driven synthesis.

Carotid endarterectomy versus carotid stenting for asymptomatic carotid stenosis: Evaluating the overlapping meta-analyses of randomized controlled trials.

Background: Asymptomatic carotid stenosis is associated with increased risk of ischemic stroke. The management of asymptomatic carotid stenosis ranges from open surgical approaches, minimally invasive endovascular interventions, and medical therapeutics. However, the research synthesis comparing these interventions, as shown by the scattered and overlapping published meta-analysis, has been inconsistent and non-comprehensive. Methods: Using previously-employed methods, we searched for and compared published meta-analyses comparing carotid endarterectomy and carotid stenting. A comprehensive search was conducted for all relevant studies published until November 13th, 2021, using the following databases: PubMed/MEDLINE, Scopus, Web of Science, Cochrane Library, OVID, and Google Scholar. Results: Five meta-analysis studies were included in this review. In summary, clinical findings were: carotid endarterectomy reduced the rate of ischemic stroke and stroke-related mortality, but led to a higher rate of intraoperative cranial nerve injury. There was no significant difference between carotid endarterectomy and carotid stenting in ipsilateral stroke and myocardial infarction events. Conclusions: The clinical findings favor the carotid endarterectomy over the carotid stenting in terms of stroke incidence (overall and minor events) and stroke-related mortality rates. However, the carotid stenting was superior to the carotid endarterectomy in the events of cranial nerve injury during the intervention.

First-line thrombectomy strategy for distal and medium vessel occlusions: a systematic review.

BACKGROUND: The benefit of mechanical thrombectomy (MT) and efficacy of different first-line MT techniques remain unclear for distal and medium vessel occlusions (DMVOs). In this systematic review, we aimed to compare the performance of three first-line MT techniques in DMVOs. METHODS: The PubMed database was searched for studies examining the utility of MT in DMVOs (middle cerebral artery M2-3-4, anterior cerebral artery, and posterior cerebral artery). Studies providing data for aspiration thrombectomy (ASP), stent retriever thrombectomy (SR), and combined SR+ASP technique were included. Non-comparative studies were excluded. Safety and efficacy data were collected for each technique. The Nested Knowledge AutoLit platform was utilized for literature search, screening, and data extraction. Pooled data were presented as descriptive statistics. RESULTS: 13 studies comprising 2422 MT procedures were identified. The overall successful recanalization rate was 77.0% (1513/1964) for DMVOs. SR+ASP had a successful recanalization rate of 83.7% (297/355), SR had a 75.6% rate (638/844), while ASP alone had a 74.2% rate (386/520). The overall functional independence rate was 51.3% (851/1659) among DMVOs. The ASP alone group had a functional independence rate of 46.9% (219/467), while functional independence rates of the SR and SR+ASP groups were 51.5% (372/723) and 61.7% (174/282), respectively. Finally, the subarachnoid hemorrhage rates were 1.8% (4/217) for the ASP group, 9.3% (26/281) for the SR group, and 11.9% (41/344) for the SR+ASP group. CONCLUSIONS: Our systematic review supports the proposition that MT is a safe and effective treatment option for DMVOs. Additionally, while the SR+ASP group had consistently high rates of clot clearance and good neurological outcomes, the SR and SR+ASP groups also had higher rates of subarachnoid hemorrhage, highlighting the need for improved DMVO treatment devices.

Common Data Elements Reported in Mechanical Thrombectomy for Acute Ischemic Stroke: A Systematic Review of Active Clinical Trials.

BACKGROUND: New trials are planned regularly to provide the highest quality of evidence and invade new occlusion territories, which requires a pre-defined reporting strategy with consistent, common data elements for more straightforward collective evidence synthesis. We sought to review all active endovascular thrombectomy trials to investigate their patient selection criteria, intervention description, and reported outcomes. METHODS: A literature search was systematically conducted on clinicaltrials.gov for active trials and all intervention, inclusion criteria, and outcomes reported were extracted. A qualitative synthesis of the frequency of study design types and data elements are graphically and narratively presented. RESULTS: A total of 32 studies were tagged and included in the final qualitative analysis. The inclusion criteria were highly variable, including different cut-offs for the last well-known baseline National Institutes of Health Stroke Scale, Alberta Stroke Program Early CT Score, and modified Rankin scale (mRS). Half of the studies (16/32) mentioned "thrombectomy" without defining which technique or device was used, and the final thrombolysis in cerebral infarction scale was provided in 19 (59.4%) studies. Heterogeneity was also present among the studies reporting a first-pass effect, both in how studies defined the outcome and in used ranges for mRS. Mortality and intracerebral hemorrhage (ICH) were more homogenous in their presentation and follow-up. CONCLUSIONS: There is a great degree of heterogeneity in the active thrombectomy trials concerning inclusion criteria, interventions used, and how outcomes are being reported.

The prognostic value of neutrophil-to-lymphocyte ratio in patients with traumatic brain injury: A systematic review.

Traumatic brain injury (TBI) places a heavy load on healthcare systems worldwide. Despite significant advancements in care, the TBI-related mortality is 30-50% and in most cases involves adolescents or young adults. Previous literature has suggested that neutrophil-to-lymphocyte ratio (NLR) may serve as a sensitive biomarker in predicting clinical outcomes following TBI. With conclusive evidence in this regard lacking, this study aimed to systematically review all original studies reporting the effectiveness of NLR as a predictor of TBI outcomes. A systematic search of eight databases was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses statement (PRISMA) recommendations. The risk of bias was assessed using the Quality in Prognostic Studies (QUIPS) tool. Eight studies were ultimately included in the study. In most of the studies interrogated, severity outcomes were successfully predicted by NLR in both univariate and multivariate prediction models, in different follow-up durations up to 6 months. A high NLR at 24 and 48 h after TBI in pediatric patients was associated with worse clinical outcomes. On pooling the NLR values within studies assessing its association with the outcome severity (favorable or not), patients with favorable outcomes had 37% lower NLR values than those with unfavorable ones (RoM= 0.63; 95% CI = 0.44-0.88; p = 0.007). However, there were considerable heterogeneity in effect estimates (I 2 = 99%; p < 0.001). Moreover, NLR was a useful indicator of mortality at both 6-month and 1-year intervals. In conjunction with clinical and radiographic parameters, NLR might be a useful, inexpensive marker in predicting clinical outcomes in patients with TBI. However, the considerable heterogeneity in current literature keeps it under investigation with further studies are warranted to confirm the reliability of NLR in predicting TBI outcomes.

Correction: Web-Based Software Tools for Systematic Literature Review in Medicine: Systematic Search and Feature Analysis.

[This corrects the article DOI: 10.2196/33219.].

Mechanical thrombectomy in anterior vs. posterior circulation stroke: A systematic review and meta-analysis.

BACKGROUND: High-quality evidence exists for mechanical thrombectomy (MT) treatment of acute ischemic stroke (AIS) due to large vessel occlusion of the anterior circulation (AC-LVO). The evidence for MT treatment of posterior circulation large vessel occlusion (PC-LVO) is weaker, largely drawn from lower quality studies specific to PC-LVO and extrapolated from findings in AC-LVO, and ambiguous with regards to technical success. We performed a systematic review and meta-analysis to compare the technical success and functional outcomes of MT in PC-LVO versus AC-LVO patients. METHODS: We identified comparative studies reporting on patients treated with MT in AC-LVO versus PC-LVO. The primary outcome of interest was thrombolysis in cerebral infarction (TICI) ≥ 2b. Secondary outcomes included rates of TICI 3, 90-day functional independence, first-pass-effect, average number of passes, and 90-day mortality. A separate random effects model was fit for each outcome measure. RESULTS: Twenty studies with 12,911 patients, 11,299 (87.5%) in the AC-LVO arm and 1612 (12.5%) in the PC-LVO arm, were included. AC-LVO and PC-LVO patients had comparable rates of successful recanalization [OR = 1.02 [95% CI: 0.79-1.33], p = 0.848). However, the AC-LVO group had greater odds of 90-day functional independence (OR = 1.26 [95% CI: 1.00; 1.59], p = 0.050) and lower odds of 90-day mortality (OR = 0.58 [95% CI: 0.43; 0.79], p = 0.002). CONCLUSIONS: MT achieves similar rates of recanalization with a similar safety profile in PC-LVO and AC-LVO patients. Patients with PC-LVO are less likely to achieve functional independence after MT. Future studies should identify PC-LVO patients who are likely to achieve favourable functional outcomes.