A Pre-Interventional Scale to Predict in situ Atherosclerotic Thrombosis in Acute Vertebrobasilar Artery Occlusion Patients

Application of 3D-PCASL combined with t-ASL and MRA in the diagnosis of patients with isolated vertigo induced by posterior circulation ischemia

OBJECTIVES

Isolated vertigo induced by posterior circulation ischemia (PCIV) can further progress into posterior circulation infarction. This study aimed to explore the diagnostic values of three-dimensional pseudo-continuous arterial spin labeling (3D-PCASL) combined with territorial arterial spin labeling (t-ASL) and magnetic resonance angiography (MRA) in visualizing and evaluating PCIV, seeking improved diagnostic tools for clinical guidance.

METHODS

28 PCIVs (11 males, 17 females, aged from 55 to 83 years, mean age: 69.68 ± 9.01 years) and 28 healthy controls (HCs, 12 male, 16 female, aged from 56 to 87 years, mean age: 66.75 ± 9.86 years) underwent conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), MRA, 3D-PCASL, and t-ASL. We compared the incidence of anatomic variants of the posterior circle of Willis in MRA, cerebral blood flow (CBF) and anterior collateral blood flow on postprocessing maps obtained from 3D-PCASL and t-ASL sequence between PCIVs and HCs. Chi-square test and paired t-test were analyzed statistically with SPSS 24.0 software.

RESULTS

7 PCIVs (7/28, 25%) and 6 HCs (6/28, 21%) showed fetal posterior cerebral artery (FPCA) on MRA, including 1 HC, and 6 PCIVs with FPCA appeared hypoperfusion. 18 PCIVs (64%) and 2 HCs (7%) showed hypoperfusion in the posterior circulation (PC), including 1 HC and 7 PCIVs displayed anterior circulation collateral flow. Chi-square analyses demonstrated a difference in PC hypoperfusion between PCIVs and HCs, whether in the whole or FPCA-positive group assessment (P < 0.05). Paired t-test showed that the CBF values were significant difference for the bilateral PC asymmetrical perfusion in the PCIVs (P < 0.01). When compared to the bilateral PC symmetrical non-hypoperfusion area in the PCIVs and HCs, the CBF values were not significant (P > 0.05). The CBF values of the PC in PCIVs were lower than in HCs (P < 0.05). The reduction rate in the hypoperfusion side of the bilateral PC asymmetrical perfusion of the PCIVs ranged from 4% to 37%, while the HCs reduction rate was 7.7%. The average PC symmetrical perfusion average reduction rate of the PCIVs was 52.25%, while the HCs reduction rate was 42.75%.

CONCLUSION

3D-PCASL is a non-invasive and susceptible method for detecting hypoperfusion in PC, serving as a potential biomarker of PCIV. The suspected hypoperfusion in PC may be attributed to the emergence of FPCA and the manifestation of anterior collateral flow when combining t-ASL and MRA sequences. These findings demonstrated that 3D-PCASL combined with t-ASL and MRA sequences are the potential method to identify PCIV, leading to early diagnosis of PCIV and reducing the risk of progressing into infarction.

Emergent Large Vessel Occlusion due to Intracranial Stenosis: Identification, Management, Challenges, and Future Directions

This comprehensive literature review focuses on acute stroke related to intracranial atherosclerotic stenosis (ICAS), with an emphasis on ICAS-large vessel occlusion. ICAS is the leading cause of stroke globally, with high recurrence risk, especially in Asian, Black, and Hispanic populations. Various risk factors, including hypertension, diabetes, hyperlipidemia, smoking, and advanced age lead to ICAS, which in turn results in stroke through different mechanisms. Recurrent stroke risk in patients with ICAS with hemodynamic failure is particularly high, even with aggressive medical management. Developments in advanced imaging have improved our understanding of ICAS and ability to identify high-risk patients who could benefit from intervention. Herein, we focus on current management strategies for ICAS-large vessel occlusion discussed, including the use of perfusion imaging, endovascular therapy, and stenting. In addition, we focus on strategies that aim at identifying subjects at higher risk for early recurrent risk who could benefit from early endovascular intervention The review underscores the need for further research to optimize ICAS-large vessel occlusion treatment strategies, a traditionally understudied topic.

Large Vessel Occlusion Stroke due to Intracranial Atherosclerotic Disease: Identification, Medical and Interventional Treatment, and Outcomes

Large vessel occlusion stroke due to underlying intracranial atherosclerotic disease (ICAD-LVO) is prevalent in 10 to 30% of LVOs depending on patient factors such as vascular risk factors, race and ethnicity, and age. Patients with ICAD-LVO derive similar functional outcome benefit from endovascular thrombectomy as other mechanisms of LVO, but up to half of ICAD-LVO patients reocclude after revascularization. Therefore, early identification and treatment planning for ICAD-LVO are important given the unique considerations before, during, and after endovascular thrombectomy. In this review of ICAD-LVO, we propose a multistep approach to ICAD-LVO identification, pretreatment and endovascular thrombectomy considerations, adjunctive medications, and medical management. There have been no large-scale randomized controlled trials dedicated to studying ICAD-LVO, therefore this review focuses on observational studies.

Predictors and outcomes of first pass efficacy in posterior circulation strokes: Insights from STAR collaboration

Background: First-pass efficacy (FPE) has been established as an important predictor of favorable functional outcomes after endovascular thrombectomy (ET) in anterior circulation strokes. In this retrospective cohort study, we investigate predictors and clinical outcomes of FPE in posterior circulation strokes (pcAIS). Methods: The Stroke Thrombectomy and Aneurysm Registry database was used to identify pcAIS patients who achieved FPE. Their baseline characteristics and outcomes were compared with the non-FPE group. The primary outcome was a 90-day modified Rankin Scale (mRS) of 0-3. Univariate (UVA) and multivariate (MVA) analyses were done to evaluate predictors of FPE. Safety outcomes included distal emboli, vessel rupture, symptomatic intracranial hemorrhage, and mortality. Results: Of 359 patients, 179 (50%) achieved FPE. Clot burden, occlusion site, and ET technique-related variables were similar between the two groups except for shorter procedure time with FPE. The primary outcome was significantly better with FPE (56.4% vs. 32.8%, p < 0.001). Complications were similar except for a higher rate of distal emboli in non-FPE group (11.1% vs. 3.2%, p = 0.032). Atrial fibrillation (Afib) had increased odds (aOR: 2.06, 95% CI; 1.24, 3.4, p = 0.005) and prior ischemic stroke had decreased odds (aOR: 0.524, 95% CI; 0.28, 0.97, p = 0.04) of FPE. Afib was the only independent predictor of FPE on MVA (1.94, 95% CI; 1.1, 3.43, p = 0.022). Conclusions: Higher rate of FPE in Afib-related pcAIS could possibly be explained by the differences in clot composition and degree of in-situ atherosclerotic disease burden. Future studies are warranted to explore the relationship of clot composition with ET outcomes.

A Clinical Prediction Model for Patients with Acute Large Vessel Occlusion Due to Underlying Intracranial Atherosclerotic Stenosis

Background

Acute large vessel occlusion due to underlying intracranial atherosclerotic stenosis (ICAS-LVO) increases the difficulty of revascularization, resulting in frequent re-occlusion. The establishment of its pathogenesis before endovascular treatment (EVT) is beneficial for patients. We aimed at developing and validating a clinical prediction model for ICAS-LVO patients before EVT.

Methods

Patients with acute large vessel occlusion at Jining No. 1 People’s Hospital from January 2019 to September 2021 were retrospectively included as the training cohort. The 70 patients who met the inclusion and exclusion criteria were included in the validation cohort (October 2021 to May 2022). Demographics, onset form, medical history, digital subtraction angiography (DSA) imaging data, and laboratory test data were collected. Preprocedural parameters for the ICAS-LVO risk prediction model were established by stepwise logistic regression controlling for the confounding effects. Then, we constructed a nomogram model and evaluated its performance via the Hosmer-Lemeshow goodness-of-fit test, area under the ROC curve (AUC) analysis.

Results

The 231 acute LVO patients were included in the final analysis, 74 (32.3%) patients were ICAS-LVO. A preoperative diagnosis prediction model consisting of five predictors for ICAS-LVO, including fluctuating symptoms, NIHSS < 16, atrial fibrillation, tapered sign, and ASITN/SIR score ≥ 2. The model depicted an acceptable calibration (Hosmer-Lemeshow test, p = 0.451) and good discrimination (AUC, 0.941; 95% confidence interval, 0.910–0.971). The optimal cut-off value for the ICAS-LVO scale was 2 points, with 86.5% sensitivity, 91.1% specificity, and 90.5% accuracy. In the validation cohort, the discriminative ability was promising with an AUC value of 0.897, implying a good predictive performance.

Conclusion

The established ICAS-LVO scale, which is composed of five predictors: fluctuating symptoms, NIHSS < 16, atrial fibrillation, tapered sign, and ASITN/SIR score ≥ 2, has a good predictive value for ICAS-LVO in Chinese populations.

A simple score to predict atherosclerotic or embolic intracranial large-vessel occlusion stroke before endovascular treatment

OBJECTIVE

The authors developed a method to predict the etiology of intracranial large-vessel occlusion stroke (ILVOS) before endovascular treatment.

METHODS

The authors retrospectively evaluated two etiologies of ILVOS-intracranial atherosclerotic stenosis-related occlusion (ICAS-O) and embolism-related occlusion (EMB-O)-in a cohort of patients from the National Comprehensive Stroke Center database of China. Patients were randomly divided into the derivation and validation cohorts at a ratio of 2:1. The authors derived the score in the derivation cohort and assessed the score in the validation cohort.

RESULTS

The authors identified 608 of 662 patients with ILVOS who received endovascular treatment during the study period. After adjustment for confounding factors, hypertension (OR 2.90, 95% CI 1.34-6.26), diabetes mellitus (OR 2.80, 95% CI 1.45-5.42), absence of atrial fibrillation (OR 27.29, 95% CI 13.27-56.09), National Institutes of Health Stroke Scale score < 7 (OR 2.92, 95% CI 1.22-6.99), and absence of the computed tomography hyperdense sign (OR 2.86, 95% CI 1.22-6.74) were significantly related to ICAS-O. A score was derived to help predict ICAS-O or EMB-O. The area under the curve values of the receiver operating characteristic curve for ICAS-O identification were 0.886 (95% CI 0.839-0.933) and 0.880 (95% CI 0.846-0.914) in the derivation and validation cohorts, respectively.

CONCLUSIONS

The atrial fibrillation-blood pressure-clinical neurological deficit-computed tomography hyperdense sign-diabetes mellitus (ABC2D) score can be used to identify atherosclerotic or embolic etiology of patients with ILVOS who require emergency endovascular treatment.