FLAIR vascular hyperintensities predict functional outcome after endovascular thrombectomy in patients with large ischemic cores

To bridge or not to bridge: The role of intravenous thrombolysis in mechanical thrombectomy for large cerebral infarctions through a two-center cohort study and meta-analysis

BACKGROUND

The effectiveness and safety of intravenous thrombolysis before mechanical thrombectomy (MT) in large cerebral infarctions remains uncertain. This study compares bridging MT, which includes intravenous thrombolysis, to direct MT without it.

METHODS

Data from 298 patients with anterior circulation large cerebral infarctions, assessed via non-enhanced CT (ASPECTS 0-5), who underwent MT in two-center cohort studies, were analyzed. Primary outcomes focused on independent ambulation (modified Rankin Scale scores 0-3) at 90 days post-stroke. Safety outcomes included parenchymal hemorrhage (PH) rates and mortality. We conducted a sensitivity analysis considering the timing from symptom onset to imaging within 4.5 hours. Additionally, a meta-analysis of 17 studies involving 3527 patients assessed the interventions' effectiveness and safety, with further scrutiny of high-quality studies (Newcastle-Ottawa Scale ratings 7-9) to increase robustness of results.

RESULTS

No significant differences were found in 90-day independent ambulation between the bridging MT and the direct MT group (adjusted odds ratio [aOR] 1.15, 95% CI 0.68-1.94). Rates of PH and mortality were also similar across groups. These outcomes were consistent in the subgroup imaged within 4.5 hours of symptom onset. The meta-analysis supported these outcomes, showing no improvement in ambulation (aOR 1.16, 95% CI 0.82-1.64) or reduction in PH with bridging MT. Further analysis of high-quality studies supported these results.

CONCLUSIONS

The cohort study and meta-analysis provide Class II evidence indicating no significant differences in functional outcomes or hemorrhagic risks between bridging and direct MT for large cerebral infarctions. This suggests that direct MT might be a viable alternative to bridging MT.

Outcome prediction comparison of ischaemic areas' radiomics in acute anterior circulation non-lacunar infarction

The outcome prediction of acute anterior circulation non-lacunar infarction (AACNLI) is important for the precise clinical treatment of this disease. However, the accuracy of prognosis prediction is still limited. This study aims to develop and compare machine learning models based on MRI radiomics of multiple ischaemic-related areas for prognostic prediction in AACNLI. This retrospective multicentre study consecutively included 372 AACNLI patients receiving MRI examinations and conventional therapy between October 2020 and February 2023. These were grouped into training set, internal test set and external test set. MRI radiomics features were extracted from the mask diffusion-weighted imaging, mask apparent diffusion coefficient (ADC) and mask ADC620 by AACNLI segmentations. Grid search parameter tuning was performed on 12 feature selection and 9 machine learning algorithms, and algorithm combinations with the smallest rank-sum of area under the curve (AUC) was selected for model construction. The performances of all models were evaluated in the internal and external test sets. The AUC of radiomics model was larger than that of non-radiomics model with the same machine learning algorithm in the three mask types. The radiomics model using least absolute shrinkage and selection operator-random forest algorithm combination gained the smallest AUC rank-sum among all the algorithm combinations. The AUC of the model with ADC620 was 0.98 in the internal test set and 0.91 in the external test set, and the weighted average AUC in the three sets was 0.96, the largest among three mask types. The Shapley additive explanations values of the maximum of National Institute of Health Stroke Scale score within 7 days from onset (7-d NIHSSmax), stroke-associated pneumonia and admission Glasgow coma scale score ranked top three among the features in AACNLI outcome prediction. In conclusion, the random forest model with mask ADC620 can accurately predict the AACNLI outcome and reveal the risk factors leading to the poor prognosis.

FLAIR vascular hyperintensity is associated with functional outcome in patients with ischemic stroke receiving endovascular treatment: a meta-analysis

Background

Fluid-attenuated inversion recovery (FLAIR) vascular hyperintensity (FVH) might be useful for predicting and functional outcome in ischemic stroke patients after endovascular thrombectomy (EVT), but its clinical benefit remains controversial. Thus, this study aimed to evaluate the association of FVH on prognosis in ischemic stroke patients who received EVT.

Methods

PubMed, Embase, Cochrane Library, Web of Science, and Wanfang databases were searched for potentially eligible studies published up to March 2024. Pooled standard mean difference (SMD), risk ratios (RR) with 95% confidence intervals (CI) were employed to assess the association of FVH on prognosis in ischemic stroke patients who received EVT. All statistical analyses were conducted using STATA 12.0 software.

Results

A total of 10 studies were included in our study. The results indicated that higher FVH score were associated with better prognosis (SMD: 0.80, 95% CI 0.63-0.97). Moreover, the presence of FVH was significant associated with better functional outcome in ischemic stroke patients who received EVT (RR: 0.68, 95% CI, 0.58-0.79).

Conclusion

The current meta-analysis suggests that FVH is related the prognosis of ischemic stroke patients after EVT.

Relationship between the intravascular enhancement sign on three-dimensional T1-weighted turbo spin echo and intraluminal thrombus in middle cerebral artery atherosclerosis

PURPOSE

To investigate the association between the intravascular enhancement sign (IVES) and intraluminal thrombus (ILT) detected by high-resolution magnetic resonance vessel wall imaging (HR-VWI) in patients with middle cerebral artery (MCA) atherosclerosis.

METHOD

The data of patients who underwent HR-VWI between May 2021 and May 2023, including clinical information, the number of IVES vessels, stenosis degree, ILT, plaque features on 3D T1-weighted turbo spin echo sequences, and signal intensity ratio (SIR) on 3D time-of-flight magnetic resonance angiography, were retrospectively analyzed. Correlation and logistic regression analyses were performed.

RESULTS

A total of 194 MCA plaques were identified in 132 patients (103 [53 %] on the left). Atherosclerosis with, relative to without, ILT was associated with a higher incidence of ischemic events, higher plaque enhancement and stenosis degrees, more vessels with IVES, and lower remodeling ratio, lumen area, wall area, total vessel area, and SIR. Multivariate logistic regression analysis showed significant and independent associations of the number of IVES vessels (OR = 1.089; 95 % CI [1.013-1.170]; P = 0.020) and SIR (OR = 0.007; 95 % CI [0.0004-0.124]; P < 0.001) with ILT. The number of vessels with the IVES (AUC = 0.81, 95 % CI [0.75-0.87]; P < 0.001) and SIR (AUC = 0.88, 95 % CI [0.82-0.94]; P < 0.001) sufficiently diagnosed ILT, and the AUC of the combination of the IVES and SIR was 0.89 (95 % CI [0.84-0.94]; P < 0.001).

CONCLUSION

The number of IVES vessels and SIR are independent risk factors for ILT. They may provide new monitoring targets for stroke prevention in patients with atherosclerotic stenosis.

Endovascular therapy for acute stroke with a large infarct core: A systematic review and meta-analysis

OBJECTIVE

In this meta-analysis, we aimed to investigate the efficacy and safety of endovascular treatment (EVT) for acute ischemic stroke (AIS) patients with large core infarct.

METHODS

Three online databases of Web of Science, PubMed and Scopus were systematically searched. Original studies which evaluated AIS participants with large core infarction who underwent EVT were included. R statistical software was used for statistical analyses. Effect sizes were presented with odds ratios (ORs) with their 95% confidence intervals (CIs). The effect sizes were pooled using random effects modeling.

RESULTS

Including 47 studies and 15,173 patients, this meta-analysis showed that compared with medical management (MM), EVT was significantly associated with decreased odds of mortality (0.67, 95% CI: 0.51-0.87) and increased odds of favorable outcomes, including a modified Rankin Scale of 0-3 (2.36, 95% CI: 1.69-3.291) and of 0-2 (3.54, 95% CI: 1.96-6.4) in 90 days and remarkable improvement in National Institutes of Health Stroke Scale within 48 h after the procedure (3.6, 95% CI:1.32-9.79). Besides, there was a higher chance of intracranial hemorrhage (ICH) development (1.88, 95% CI: 1.32-2.68) but not symptomatic ICH (1.34, 95% CI: 0.78-2.31) in those who underwent EVT.

CONCLUSION

Our study suggests that EVT might be an effective and relatively safe treatment option for the treatment of AIS patients with large vessel occlusion who have large core infarcts, although more large-scale trials are needed to consolidate the results and to make inclusion criteria and the patient selection process clearer.

Endovascular therapy versus medical management for acute ischemic stroke with large infarct core: Systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

To compare the efficacy and safety of endovascular therapy (EVT) versus best medical management (BMM) in patients with acute ischemic stroke (AIS) with large infarct core.

METHODS

We searched Pubmed, Embase and Cochrane Central Register of Controlled Trials for published randomized clinical trials (RCTs) from inception to February 18, 2023. We defined patients with large core infarcts as having an Alberta Stroke Program early computed tomography score (ASPECTS) of 3-5. The primary outcome was functional independence, defined as a score of 0-2 on the modified Rankin scale (mRS) at 90 days. Secondary outcome was independent ambulation defined as mRS 0-3 at 90 days. Safety outcomes were mortality at 90 days, symptomatic intracranial hemorrhage (sICH) and any intracranial hemorrhage (ICH).

RESULTS

The overall treatment effect was more favourable to EVT group. EVT was significantly correlated with improvement of functional independence at 90 days (mRS 0-2) (RR = 2.40; 95 % CI, 1.82-3.16; P < 0.01; I2 = 0 %) and independent ambulation (mRS 0-3) (RR = 1,78; 95 % CI, 1.28-2.48; P < 0.01; I2 = 58 %) at 90 days. 90-day mortality was not significantly different between the two groups(RR = 0.95; 95 % CI, 0.78-1.16; P > 0.05; I2 = 0 %). The risk of sICH and any ICH was higher in EVT group than in BMM group.

CONCLUSION

Compared with BMM, EVT may improve functional outcomes in patients with ASPECTS 3-5, despite being associated with an increased risk of sICH and any ICH.

Individualized interpretation for the clinical significance of fluid-attenuated inversion recovery vessel hyperintensity in ischemic stroke and transient ischemic attack: A systematic narrative review

Fluid-attenuated inversion recovery (FLAIR) vessel hyperintensity（FVH）refers to the hyperintensity corresponding to the arteries in the subarachnoid space. It is caused by critically slowed blood flow and is commonly encountered in patients with large artery steno-occlusions. Quite a few studies have focused on the clinical significance of FLAIR vessel hyperintensity in terms of its relationship to the prognosis of transient ischemic attack (TIA), baseline severity or infarction volume, early neurological deterioration or infarction growth, and functional outcomes in acute ischemic stroke (AIS). However, inconsistent or conflicting findings were common in these studies and caused confusion in the clinical decision-making process guided by this imaging marker. Through reviewing the available studies on the etiologic mechanism of FVH and investigating findings on its clinical significance in AIS and TIA, this review aims to elucidate the key factors for interpreting the clinical significance of FVH individually.

Endovascular treatment for anterior circulation large-vessel occlusion ischemic stroke with low ASPECTS: a systematic review and meta-analysis

BACKGROUND

Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with Alberta Stroke Program Early CT Score (ASPECTS) 0-5 has not yet proven safe and effective by clinical trials.

OBJECTIVES

The aim of the study was to assess whether EVT in AIS patients presenting with low ASPECTS is beneficial.

DESIGN

Systematic review and meta-analysis of available studies in accordance with the PRISMA statement.

DATA SOURCES AND METHODS

We have searched MEDLINE, the Cochrane Central Register of Controlled Trials, and reference lists of articles published until 28 May 2022 with the aim to calculate (1) modified Rankin scale (mRS) score 0-3 at 3 months, (2) mRS score 0-2 at 3 months, (3) symptomatic intracranial hemorrhage (sICH), and (3) mortality at 3 months.

RESULTS

Overall, 24 eligible studies were included in the meta-analysis, comprising a total of 2539 AIS patients with ASPECTS 0-5 treated with EVT. The pooled proportion of EVT-treated patients achieving mRS 0-3 at 3 months was calculated at 38.4%. The pooled proportion of EVT-treated patients achieving mRS 0-2 at 3 months was 25.7%. Regarding safety outcomes, sICH occurred in 12.8% of patients. The 3-month pooled mortality was 30%. In pairwise meta-analysis, patients treated with EVT had a higher likelihood of achieving mRS 0-3 at 3 months compared with patients treated with best medical therapy (BMT, OR: 2.41). sICH occurred more frequently in EVT-treated patients compared with the BMT-treated patients (OR: 2.30). Mortality at 3 months was not different between the two treatment groups (OR: 0.71).

CONCLUSION

EVT may be beneficial for AIS patients with low baseline ASPECTS despite an increased risk for sICH. Further data from randomized-controlled clinical trials are needed to elucidate the role of EVT in this subgroup of AIS patients.

REGISTRATION

The protocol has been registered in the International Prospective Register of Ongoing Systematic Reviews PROSPERO; Registration Number: CRD42022334417.

Editorial comment: Prognostic value of post-treatment fluid-attenuated inversion recovery vascular hyperintensity in ischemic stroke after endovascular thrombectomy

KEY POINTS

• The fluid-attenuated inversion recovery vascular hyperintensity (FVH) sign on FLAIR has been reported as a surrogate marker to predict collateral status and clinical outcome in patients with stroke. Most previous studies on the relationship between FVH and prognosis generally focused on the pre-treatment of stroke.• This article focused on FVH in AIS patients with LVO post-treatment EVT. It proved that the post-treatment FVH sign may be associated with poor clinical outcome. It may offer an additional imaging biomarker for the prognosis evaluation of EVT patients.