Alberta Stroke Program Early CT Score Research Articles

Comparison of Thrombolysis In Cerebral Infarction (TICI) 2b and TICI 3 reperfusion in endovascular therapy for large ischemic anterior circulation strokes

BackgroundLandmark thrombectomy trials have provided evidence that selected patients with large ischemic stroke benefit from successful endovascular therapy, commonly defined as incomplete (modified Thrombolysis In Cerebral Infarction (mTICI) 2b) or...

Mode of Imaging Study and Endovascular Therapy for a Large Ischemic Core: Insights From the RESCUE-Japan LIMIT.

Differences in measurement of the extent of acute ischemic stroke using the Alberta Stroke Program Early Computed Tomographic Score (ASPECTS) by non-contrast computed tomography (CT-ASPECTS stratum) and diffusion-weighted imaging (DWI-ASPECTS stratum) may impact the efficacy of endovascular therapy (EVT) in patients with a large ischemic core. The RESCUE-Japan LIMIT (Recovery by Endovascular Salvage for Cerebral Ultra-acute Embolism Japan-Large IscheMIc core Trial) was a multicenter, open-label, randomized clinical trial that evaluated the efficacy and safety of EVT in patients with ASPECTS of 3-5. CT-ASPECTS was prioritized when both CT-ASPECTS and DWI-ASPECTS were measured. The effects of EVT on the modified Rankin Scale (mRS) score at 90 days were assessed separately for each stratum. Among 183 patients, 112 (EVT group, 53; No-EVT group, 59) were in the CT-ASPECTS stratum and 71 (EVT group, 40; No-EVT group, 31) in the DWI-ASPECTS stratum. The common odds ratio (OR) (95% confidence interval) of the EVT group for one scale shift of the mRS score toward 0 was 1.29 (0.65-2.54) compared to the No-EVT group in CT-ASPECTS stratum, and 6.15 (2.46-16.3) in DWI-ASPECTS stratum with significant interaction between treatment assignment and mode of imaging study (P=0.002). There were significant interactions in the improvement of the National Institutes of Health Stroke Scale score at 48 hours (CT-ASPECTS stratum: OR, 1.95; DWIASPECTS stratum: OR, 14.5; interaction P=0.035) and mortality at 90 days (CT-ASPECTS stratum: OR, 2.07; DWI-ASPECTS stratum: OR, 0.23; interaction P=0.008). Patients with ASPECTS of 3-5 on MRI benefitted more from EVT than those with ASPECTS of 3-5 on CT.

Nonenhanced Computed Tomography Evaluation Of Ischemic Stroke Patients Presenting After 4.5 Hours From Onset Of Symptoms Using Aspects, Posterior Circulation-Aspects And X-Ray Attenuation Ratio: The “Tissue Window”

Background: Stroke is a major cause of disability and mortality world-wide. Ischemic stroke is reversible when patients present early. With the current treatment guideline in Nigeria, most ischemic stroke patients present after the 4.5 hours treatment “time window” and are ineligible for intravenous thrombolysis (IVT). However, studies with computed tomography and magnetic resonance imaging have shown variability in the duration of tissue viability, with some remaining viable up to 24 hours and beyond. These advanced imaging are not readily available in the sub-Saharan Africa but the X-ray attenuation ratio of hypoattenuating lesions on the easily accessible nonenhanced computed tomography (NECT), have recently shown to be a valuable alternative. In late presentation, IVT and endovascular thrombectomy (EVT) have proven to have reasonable degree of success in recanalization. Hence, the need for the study.
 Materials and method: This was a retrospective cross-sectional study of ischemic stroke patients who presented between 4.5 and 24 hours for NECT. The extent of the ischemia was determined using the Alberta stroke programme early CT score (ASPECTS), while the Hounsfield unit ratio of the hypodense lesions was used to determine tissue viability.
 Results: Fifty-five patients met the inclusion criteria and had a mean age of 58.8 years. Four (7.27%) patients clearly had ASPECTS and Hounsfield unit ratio (HUr) scores suggestive of salvageable penumbral tissue, while another four (7.27%) had the probability of being reversible.
 Conclusion: Some patients were still eligible for treatment after the current guideline’s 4.5 hours treatment “time window” using the ASPECTS and HUr scores on NECT.
 

Endovascular Thrombectomy in Patients With Very Low ASPECTS Scores: A Systematic Review and Meta-analysis.

Randomized controlled trials (RCTs) have recently established the benefit of endovascular thrombectomy (EVT) in patients with large infarct core on baseline neuroimaging. We evaluated the utility of EVT in patients with very large infarct core, defined as Alberta Stroke Program Early CT scores (ASPECTS) of less than 3. We performed a systematic review and meta-analysis of the subgroups of patients with baseline ASPECTS scores 0-2 included in RCTs evaluating the utility of EVT in the setting of a large infarct core. The outcome of interest was the probability of three-month functional improvement assessed with the generalized odds ratios (ORs) of the modified Rankin Scale (mRS) scores between patients receiving EVT and medical management. In the pooled analyses of 82 participants of the total 808 (10%) enrolled in 2 individual trials, we found a statistically significant shift in the distribution of mRS scores toward better outcomes in favor of EVT (generalized OR 1.46, 95% CI 1.03-2.07). No evidence of heterogeneity was detected (I 2 = 0%; p for Cochran Q = 0.73). The results from our pooled analysis challenge the exclusion of patients presenting with ASPECTS scores less than 3 from receiving EVT if they are otherwise eligible.

Comprehensive Meta-Analysis of Futile Recanalization in Acute Ischemic Stroke Patients Undergoing Endovascular Thrombectomy: Prevalence, Factors, and Clinical Outcomes.

Futile recanalization (FR) continues to raise concern despite the success of endovascular thrombectomy (EVT) in acute ischemic stroke (AIS). Understanding the prevalence of FR and identifying associated factors are crucial for refining patient prognoses and optimizing management strategies. This study aims to comprehensively assess the pooled prevalence of FR, explore the diverse factors connected with FR, and establish the association of FR with long-term clinical outcomes among AIS patients undergoing EVT. Incorporating studies focusing on FR following EVT in AIS patients, we conducted a random-effect meta-analysis to assess the pooled prevalence and its association with various clinical and imaging risk factors linked to FR. Summary estimates were compiled and study heterogeneity was explored. Our comprehensive meta-analysis, involving 11,700 AIS patients undergoing EVT, revealed a significant pooled prevalence of FR at 51%, with a range of 48% to 54% (Effect Size [ES]: 51%; 95% Confidence Interval [CI]: 48-54%; z = 47.66; p < 0.001). Numerous clinical factors demonstrated robust correlations with FR, including atrial fibrillation (Odds Ratio [OR]: 1.39, 95% CI 1.22 1.59; p < 0.001), hypertension (OR 1.65, 95% CI 1.41 1.92; p < 0.001), diabetes mellitus (OR 1.71, 95% CI 1.47 1.99; p < 0.001), previous stroke or transient ischemic attack (OR 1.298, 95% CI 1.06 1.59; p = 0.012), prior anticoagulant usage (OR 1.33, 95% CI 1.08 1.63; p = 0.007), cardioembolic strokes (OR 1.34, 95% CI 1.10 1.63; p = 0.003), and general anesthesia (OR 1.53, 95% CI 1.35 1.74; p < 0.001). Conversely, FR exhibited reduced likelihoods of smoking (OR 0.66, 95% CI 0.57 0.77; p < 0.001), good collaterals (OR 0.33, 95% CI 0.23 0.49; p < 0.001), male sex (OR 0.87, 95% CI 0.77 0.97; p = 0.016), and intravenous thrombolysis (IVT) (OR 0.75, 95% CI 0.66 0.86; p < 0.001). FR was strongly associated with increasing age (standardized mean difference [SMD] 0.49, 95% CI 0.42 0.56; p < 0.0001), baseline systolic blood pressure (SMD 0.20, 95% CI 0.13 0.27; p < 0.001), baseline National Institute of Health Stroke Severity Score (SMD 0.75, 95% CI: 0.65 0.86; p < 0.001), onset-to-treatment time (SMD 0.217, 95% CI 0.13 0.30; p < 0.001), onset-to-recanalization time (SMD 0.38, 95% CI 0.19; 0.57; p < 0.001), and baseline blood glucose (SMD 0.31, 95% CI 0.22 0.41; p < 0.001), while displaying a negative association with reduced baseline Alberta Stroke Program Early CT Score (ASPECTS) (SMD -0.37, 95% CI -0.46 -0.27; p < 0.001). Regarding clinical outcomes, FR was significantly associated with increased odds of symptomatic intracranial hemorrhages (OR 7.37, 95% CI 4.89 11.12; p < 0.001), hemorrhagic transformations (OR 2.98, 95% CI 2.37 3.75; p < 0.001), and 90-day mortality (OR 19.24, 95% CI 1.57 235.18; p = 0.021). The substantial prevalence of FR, standing at approximately 51%, warrants clinical consideration. These findings underscore the complexity of FR in AIS patients and highlight the importance of tailoring management strategies based on individual risk factors and clinical profiles.

Mechanical thrombectomy after 6 hours from the symptoms onset in acute ischemic stroke in the carotid basin due to the large vessel occlusion

Objective ‒ to assess the safety and effectiveness of mechanical thrombectomy performed no later than 6 years after the onset of symptoms in patients with ischemic stroke in the carotid basin due to occlusion of a large vessel.Materials and methods. The results of a retrospective analysis of the register of patients who received treatment at the Scientific-practical Center of endovascular neuroradiology NAMS of Ukraine in the period from 01.01.2021 to 25.12.2022 for acute ischemic stroke in the carotid basin due to occlusion of a large vessel of the brain are presented. We selected 106 patients who were functionally independent before stroke (0‒2 points on the modified Rankin Scale) and who underwent arterial puncture on the operating table for mechanical thrombectomy later 6 hours after appearance the first symptoms of stroke. The age of the patients ranged from 27 to 86 years (average age ‒ 67.3 years). There were 49 (46.2 %) men, 57 (53.8 %) women.All patients underwent multimodal neuroimaging: computed tomography (CT) of the brain, CT angiography of extracranial and intracranial cerebral arteries, or digital subtraction cerebral angiography. Quantitative assessment of initial ischemic changes in the middle cerebral artery basin was performed using the ASPECTS (Alberta Stroke Program Early CT Score). The ACG scale (American Society of Interventional and Therapeutic Neuroradiology collateral grading) was used to assess collateral blood flow.Results. The main subtype of ischemic stroke was cardioembolic ‒ 76 (71.7 %) observations. The atherothrombotic subtype occurred in 20 (18.9 %) patients. Other subtypes (cryptogenic, dissection) were diagnosed in 10 (9.4 %) cases. Occlusions in the middle cerebral artery basin were diagnosed in 69 (65.1 %) cases, tandem occlusions (internal carotid artery ‒ middle cerebral artery) were detected in 28 (26.4 %) patients. Isolated thrombosis of the internal carotid artery (I-occlusion) and T-occlusion were noted in 9 (8.5 %) observations. Well-defined collaterals (ACG score 3–4) were observed in 78 (73.6 %) patients. The group of patients with mild collateral compensation (ACG 2) accounted for 28 (26.4 %) cases. In patients within 6 to 24 hours after the onset of stroke symptoms, high-quality reperfusion (eTICI 2b-3) was achieved in 90 (84.9 %) observations. Intraoperative complications were recorded in 13 (12.3 %) cases. Among them, embolism of new arterial pools was noted in 10 (9.4 %) patients, dissection of the internal carotid artery in 1 (0.9 %) and intracranial hemorrhage due to perforation/rupture of the artery in 2 (1.9 %). Good functional results of treatment (mRS 0–2) after 90 days were observed in 54 (50.9 %) patients.Conclusions. Mechanical thrombectomy performed later than 6 hours after the onset of symptoms in acute ischemic stroke in the carotid basin due to large vessel occlusion in patients with good neuroimaging results is safe and effective.

Prediction of stress-related gastrointestinal bleeding in patients with aneurysmal subarachnoid hemorrhage using caudate Hounsfield unit value in ASPECT score.

Stress-related gastrointestinal bleeding (SRGB) is one of the major complications after aneurysmal subarachnoid hemorrhage (aSAH), and it can present challenges in patient care and treatment. The aim of this study was to explore the clinical significance of the caudate Hounsfield unit (HU) value in the Alberta Stroke Program Early CT (ASPECT) score for predicting SRGB in patients with aSAH. We retrospectively analyzed the data of 531 aSAH patients admitted to our institution between 2019 and 2022. Potential predictors of SRGB were identified using multivariate Cox regression analysis. We used a restricted cubic spline (RCS) to evaluate whether there is a nonlinear relationship between the right caudate HU value and SRGB. MaxStat analysis (titled as maximally selected rank statistics) was performed to identify the optimal cutoff point for the right caudate HU value. Another Kaplan-Meier method with the log-rank test was used to analyze the right caudate HU value in predicting the occurrence of SRGB. The incidence rate of SRGB was 17.9%. In the multivariate Cox regression analysis, the right caudate HU value was an independent predictor of SRGB [Hazard ratio (HR) = 0.913; 95% confidence interval (CI): 0.847-0.983, and p = 0.016]. The RCS indicated that the incidence of developing SRGB reduces with increasing right caudate HU values (nonlinear p = 0.78). The optimal cut-off value of the right caudate HU was 25.1. Among aSAH patients, lower right caudate HU values indicated a higher risk of developing SRGB. Our findings provide further evidence for the relationship between the gastrointestinal system and the brain.

Impact of e-ASPECTS software on the performance of physicians compared to a consensus ground truth: a multi-reader, multi-case study.

The Alberta Stroke Program Early CT Score (ASPECTS) is used to quantify the extent of injury to the brain following acute ischemic stroke (AIS) and to inform treatment decisions. The e-ASPECTS software uses artificial intelligence methods to automatically process non-contrast CT (NCCT) brain scans from patients with AIS affecting the middle cerebral artery (MCA) territory and generate an ASPECTS. This study aimed to evaluate the impact of e-ASPECTS (Brainomix, Oxford, UK) on the performance of US physicians compared to a consensus ground truth. The study used a multi-reader, multi-case design. A total of 10 US board-certified physicians (neurologists and neuroradiologists) scored 54 NCCT brain scans of patients with AIS affecting the MCA territory. Each reader scored each scan on two occasions: once with and once without reference to the e-ASPECTS software, in random order. Agreement with a reference standard (expert consensus read with reference to follow-up imaging) was evaluated with and without software support. A comparison of the area under the curve (AUC) for each reader showed a significant improvement from 0.81 to 0.83 (p = 0.028) with the support of the e-ASPECTS tool. The agreement of reader ASPECTS scoring with the reference standard was improved with e-ASPECTS compared to unassisted reading of scans: Cohen's kappa improved from 0.60 to 0.65, and the case-based weighted Kappa improved from 0.70 to 0.81. Decision support with the e-ASPECTS software significantly improves the accuracy of ASPECTS scoring, even by expert US neurologists and neuroradiologists.

Automated ASPECTS calculation may equal the performance of experienced clinicians: a machine learning study based on a large cohort.

The Alberta Stroke Program Early CT Score (ASPECTS) is a semi-quantitative method to evaluate the severity of early ischemic change on non-contrast computed tomography (NCCT) in patients with acute ischemic stroke (AIS). In this work, we propose an automated ASPECTS method based on large cohort of data and machine learning. For this study, we collected 3626 NCCT cases from multiple centers and annotated directly on this dataset by neurologists. Based on image analysis and machine learning methods, we constructed a two-stage machine learning model. The validity and reliability of this automated ASPECTS method were tested on an independent external validation set of 300 cases. Statistical analyses on the total ASPECTS, dichotomized ASPECTS, and region-level ASPECTS were presented. On an independent external validation set of 300 cases, for the total ASPECTS results, the intraclass correlation coefficient between automated ASPECTS and expert-rated was 0.842. The agreement between ASPECTS threshold of ≥ 6 versus < 6 using a dichotomized method was moderate (κ = 0.438, 0.391-0.477), and the detection rate (sensitivity) was 86.5% for patients with ASPECTS threshold of ≥ 6. Compared with the results of previous studies, our method achieved a slight lead in sensitivity (67.8%) and AUC (0.845), with comparable accuracy (78.9%) and specificity (81.2%). The proposed automated ASPECTS method driven by a large cohort of NCCT images performed equally well compared with expert-rated ASPECTS. This work further demonstrates the validity and reliability of automated ASPECTS evaluation method. The automated ASPECTS method proposed by this study may help AIS patients to receive rapid intervention, but should not be used as a stand-alone diagnostic basis. NCCT-based manual ASPECTS scores were poorly consistent. Machine learning can automate the ASPECTS scoring process. Machine learning model design based on large cohort data can effectively improve the consistency of ASPECTS scores.

Value of MRI T2 FLAIR Vascular Hyperintensities Combined with DWI ASPECTS in Predicting the Prognosis of Acute Cerebral Infarction with Endovascular Treatment.

To explore the MRI T2 fluid-attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) combined with diffusion-weighted imaging (DWI) Alberta Stroke Program Early CT Score (ASPECTS) in predicting the prognosis of acute cerebral infarction (ACI) with endovascular treatment. The patients with ACI in the anterior circulation who underwent endovascular treatment from June 2016 to December 2020 were divided into a good prognosis group and a poor prognosis group according to the modified Rankin Scale (mRS) score at 90 days after the operation. The differences in general clinical baseline data, CT-ASPECTS, FVH, and DWI-ASPECTS between the two groups were analyzed. The receiver operating characteristic (ROC) curve was used to analyze the predictive power of prediction models on prognosis. The results of the Binomial Logistic regression equation showed initial National Institute of Health stroke scale (NIHSS), Mori grade, DWI-ASPECTS, and FVH were independent risk factors for prognosis. The predictive power of the FVH + DWI-ASPECTS prediction model was highest, and the predictive power of DWI-ASPECTS was higher than that of CT-ASPECTS. DWI-ASPECTS is better than CT-ASPECTS in predicting the prognosis of ACI with endovascular treatment, and the combined prediction model of FVH and DWI-ASPECTS has higher prediction performance, which can be used as a preoperative evaluation method to predict the effect of endovascular treatment for ACI.

The role of red blood cell distribution width to platelet ratio in predicting hemorrhagic transformation after mechanical thrombectomy therapy in acute ischemic stroke patients

Objective: Hemorrhagic transformation (HT) is common complication after mechanical thrombectory (MT) for acute ischemic stroke (AIS). To our knowledge, there has been no study on the correlation between baseline red blood cell distribution width (RDW) to platelet ratio (RPR) and HT after MT. Methods: This study recruited 126 AIS patients with anterior or posterior circulation large-vessel occlusion who underwent MT therapy at the Department of Neurology, Taizhou Hospital, Zhejiang province between September 2019 and April 2021. Patients were divided into two groups: patients with HT and those without HT (wHT), and their laboratory and clinical data were compared. Results: We found no significant differences in sex, age, alcohol consumption, diabetes mellitus, atrial fibrillation, systolic blood pressure, diastolic blood pressure, triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, serum creatinine, blood urea nitrogen, fibrinogen, neutrophil count, lymphocyte count, neutrophil-to-lymphocyte ratio (NLR), National Institutes of Health Stroke Scale (NIHSS) score, Alberta Stroke Program Early Computed Tomography Score (ASPECTS), whether intravenous thrombolysis was accepted, and TOAST classification between the two groups. Compared with patients without HT, we found that the admission blood glucose, RDW and RPR levels were higher in patients with HT after MT in AIS patients, multivariate logistic regression analysis revealed that baseline RPR (odds ratio (OR), 1.290; 95% CI, 1.062–1.567; P=0.010) and glucose level (OR, 1.177; 95% CI, 1.013–1.369; P=0.034) are independent predictors for HT after MT. Conclusion: Higher baseline RPR and higher admission blood glucose levels might be related to HT in AIS patients who received MT therapy.

Influencing factors of futile recanalization after endovascular therapy in acute ischemic stroke patients with large vessel occlusions

Objective: To analyze the influencing factors of futile recanalization after endovascular therapy (EVT) in acute ischemic stroke patients with large vessel occlusions (AIS-LVO). Methods: AIS-LVO patients who underwent EVT with successful recanalization between January 2019 and December 2021 in Neurovascular Center of Changhai Hospital of Naval Medical University were retrospectively selected. Modified Rankin scale (mRS) score 3 months after EVT was used as the prognostic evaluation index, and patients with mRS scores≤2 were classified as the meaningful recanalization group and mRS scores 3-6 as the futile recanalization group. The risk factors, National Institutes of Health stroke scale (NIHSS) score, Glasgow coma scale (GCS) score, Alberta Stroke Program Early CT (ASPECT) score, core infarct volume, etc. in both groups were analyzed, and the influencing factors of futile recanalization after EVT were analyzed by multivariate logistic regression. Continuous variables that do not conform to the normal distribution are represented by [M(Q1,Q3)]. Results: A total of 368 patients meeting the inclusion criteria were collected, including 228 males and 140 females, and aged 68 (61, 77) years. There are 196 patients and 172 patients in the meaningful recanalization and futile recanalization groups, respectively, with the rate of futile recanalization 3 months after EVT of 46.74% (172/368). Comparing the general information and risk factors between the two groups found that the age of patients in the futile recanalization group [71 (65, 79) years] was higher than that in the meaningful recanalization group [65 (59, 72) years]. The baseline NIHSS score [18 (14, 22)] and the rate of not achieving modified Thrombolysis in Cerebral Ischemia grade 3 (mTICI 3) reperfusion (36.1%) were higher in the futile recanalization group than those in the meaningful recanalization group [12 (7, 17) and 19.9%]. The baseline GCS score [11 (9, 13)] was lower in the futile recanalization group than that in the meaningful recanalization group [14 (11, 15)]. The core infarct volume in the futile recanalization group [28 (7, 65) ml] was larger than that in the meaningful recanalization group [6 (0, 17) ml]. The ASPECT score [7 (5, 9)] was lower in the futile recanalization group than that in the meaningful recanalization group [9 (7, 10)]. In addition, the proportion of hypertension, atrial fibrillation, general anesthesia, and symptomatic intracranial hemorrhage was higher in the futile recanalization group (all P<0.05). The time from symptom onset to puncture and from symptom onset to reperfusion was longer in the futile recanalization group (both P<0.05). There were statistically significant differences in trial of Org 10172 in acute stroke treatment (TOAST) classification and the site of occluded blood vessels between the two groups (both P<0.05). Multivariate logistic regression indicated that age ≥80 years(OR=1.935,95%CI: 1.168-3.205), baseline NIHSS score (OR=1.999,95%CI: 1.202-3.325), GCS score (OR=2.299,95%CI: 1.386-3.814), previous stroke history (OR=1.977,95%CI: 1.085-3.604), general anesthesia (OR=1.981,95%CI: 1.143-3.435), not achieving grade 3 recanalization (OR=2.846, 95%CI: 1.575-5.143), ASPECT score<6 (OR=2.616, 95%CI: 1.168-5.857), and core infarct volume>70 ml (OR=2.712, 95%CI: 1.130-6.505) were risk factors for futile recanalization. Conclusion: Age≥80 years, previous stroke history, baseline NIHSS score≥20, GCS score≤8, general anesthesia, ASPECT score<6, core infarct volume>70 ml, and failure to achieve Grade 3 recanalization are independent influencing factors for futile recanalization after endovascular therapy in AIS-LVO patients.

Low (0–5) Alberta Stroke Program Early Computed Tomography Score on admission predictive of worse functional outcome after mechanical thrombectomy for anterior circulation large vessel occlusion

Background and purposeWe examined functional outcomes of mechanical thrombectomy (MT) procedures following anterior circulation large vessel occlusion (ACLVO)-related acute ischemic strokes (AIS). Results were based on admission non-contrast computed tomography (NCCT) studies, using the Alberta Stroke Program Early Computed Tomography Score (ASPECTS) as standard metric.MethodsQualifying subjects were consecutive patients (N = 343) at a single center undergoing MT for ACLVO-related AIS. Each was grouped according to ASPECTS status on admission, determined from NCCT images by two physicians. Primary clinical endpoint was functional independence, assessed via modified Rankin Scale (mRS) at 90 days. Secondary endpoints were vessel recanalization (i.e., modified Thrombolysis in Cerebral Infarction [mTICI] score), symptomatic intracranial hemorrhage (sICH), and mortality.ResultsIn this study population (mean age, 63.6 ± 12.6 years; women, 30.3%; median baseline National Institute of Health Stroke Scale [NIHSS] score, 15.2 ± 4.5), patients were stratified by ASPECTS tier at presentation, either 0–5 (n = 50) or 6–10 (n = 293). Multivariate logistic regression showed a relation between ASPECTS values ≤ 5 and lesser chance of 90-day functional improvement (OR = 2.309, 95% confidence interval [CI] 1.012–5.271; p = 0.047), once adjusted for age, baseline NIHSS score, diabetes mellitus, HbA1c concentration, D-dimer level, occlusive location, numbers of device passes, and successful recanalization.ConclusionsASPECTS values ≤ 5 correspond with worse long-term functional improvement (mRS scores > 2) in patients undergoing MT for ACLVO-related AIS. Other independent determinants of functional outcomes after MT are age, baseline NIHSS score, HbA1c concentration, and successful recanalization.

The Association of the Spatial Location of Contrast Extravasation with Symptomatic Intracranial Hemorrhage after Endovascular Therapy in Acute Ischemic Stroke Patients.

Contrast extravasation (CE) on brain non-contrast computed tomography (NCCT) after endovascular therapy (EVT) is commonly present in patients with acute ischemic stroke (AIS). Substantial uncertainties remain about the relationship between the spatial location of CE and symptomatic intracranial hemorrhage (sICH). Therefore, this study aimed to evaluate this association. We performed a retrospective screening on consecutive patients with AIS due to LVO (AIS-LVO) who had CE on NCCT immediately after EVT for anterior circulation large vessel occlusion (LVO). We used the Alberta stroke program early CT Score (ASPECTS) scoring system to estimate the spatial location of CE. Multivariable logistic regression was performed to achieve the risk factors of sICH. In this study, 115 of 153 (75.1%) anterior circulation AIS-LVO patients had CE on NCCT. After excluding 9 patients, 106 patients were enrolled in the final analysis. In multivariate regression analysis, atrial fibrillation (AF) (adjusted OR [aOR] 6.833, 95% confidence interval [CI] 1.331-35.081, P = 0.021) and CE-ASPECTS (aOR 0.602, 95% CI 0.411-0.882 P = 0.009) were associated with sICH. In subgroup analysis, CE at the internal capsule (IC) region was an independent risk factor for sICH (aOR 5.992, 95% CI 1.010-35.543 P < 0.05). These and conventional variables were incorporated as a predict model, with AUC of 0.899, demonstrating good discrimination and calibration for sICH in this study cohort. The spatial location of CE on NCCT immediately after EVT was an independent and strong risk factor for sICH in acute ischemic stroke patients.

Successful Thrombectomy Improves Functional Outcome in Tandem Occlusions with a Large Ischemic Core

Emergent stenting in tandem occlusions and mechanical thrombectomy (MT) of acute ischemic stroke related to large vessel occlusion (LVO-AIS) with a large core are tested independently. We aim to assess the impact of reperfusion with MT in patients with LVO-AIS with a large core and a tandem occlusion and to compare the safety of reperfusion between large core with tandem and nontandem occlusions in current practice. We analyzed data of all consecutive patients included in the prospective Endovascular Treatment in Ischemic Stroke Registry in France between January 2015 and March 2023 who presented with a pretreatment ASPECTS (Alberta Stroke Program Early CT Score) of 0-5 and angiographically proven tandem occlusion. The primary end point was a favorable outcome defined by a modified Rankin Scale (mRS) score of 0-3 at 90 days. Among 262 included patients with a tandem occlusion and ASPECTS 0-5, 203 patients (77.5%) had a successful reperfusion (modified Thrombolysis in Cerebral Infarction grade 2b-3). Reperfused patients had a favorable shift in the overall mRS score distribution (adjusted odds ratio [aOR], 1.57 [1.22-2.03]; P < 0.001), higher rates of mRS score 0-3 (aOR, 7.03 [2.60-19.01]; P < 0.001) and mRS score 0-2 at 90 days (aOR, 3.85 [1.39-10.68]; P= 0.009) compared with nonreperfused. There was a trend between the occurrence of successful reperfusion and a decreased rate of symptomatic intracranial hemorrhage (aOR, 0.5 [0.22-1.13]; P= 0.096). Similar safety outcomes were observed after large core reperfusion in tandem and nontandem occlusions. Successful reperfusion was associated with a higher rate of favorable outcome in large core LVO-AIS with a tandem occlusion, with a safety profile similar to nontandem occlusion.

Usefulness of additional diffusion MRI acquisition prior to mechanical thrombectomy for acute large vessel occlusion in the early time period at a CT-based stroke center

ObjectiveThis study aimed to investigate whether evaluating the infarction core using additionally acquired diffusion magnetic resonance imaging (MRI) could help improve the assessment of prognosis including complication rates and modify the strategy for mechanical thrombectomy in endovascular procedures at a computed tomography (CT)-based stroke center. MethodsSingle-center data from patients with acute large-vessel occlusion in the anterior circulation who underwent mechanical thrombectomy between May 2018 and January 2021 were analyzed. Diffusion MRI sequences were performed during the preparation period for mechanical thrombectomy after CT angiography. We set the infarction core reference volume on diffusion MRI to 60 cc and divided the patients into two groups: a small infarction core group (less than 60 cc) and a large infarction core group (more than 60 cc). The baseline characteristics, radiological and clinical outcomes of the patients were investigated and compared between the two groups. ResultsThe difference in numbers between the two groups was not significant in the Alberta Stroke Program Early Computed Tomography (ASPECT) score; however, the ASPECT score on diffusion MRI showed a remarkable difference between the two groups. The large infarction core volume group on diffusion MRI had a poor prognosis, with the modified Rankin score at 90 days showing a statistically significant difference (p = 0.011). Complications after the procedure, such as hemorrhagic transformation, that can occur after reperfusion, symptomatic intracerebral hemorrhage, decompressive craniectomy for increased intracranial pressure, and mortality, were significantly more frequent in the large infarction core volume group. ConclusionAt a CT-based stroke center, additionally acquired diffusion MRI without a time delay for reperfusion would improve the assessment of prognosis including complication rate, and could help neurointerventionists determine the extent of recanalization of occluded vessels during mechanical thrombectomy.

Endovascular treatment for large-core ischaemic stroke: a meta-analysis of randomised controlled clinical trials

Background and purposeCurrent guidelines recommend endovascular treatment (EVT) for acute ischaemic stroke (AIS), due to large-vessel occlusion and an Alberta Stroke Program Early CT Score (ASPECTS) of ≥6. High-quality evidence...

Association of Dual-Phase Computed Tomography Angiography and CT-Perfusion in Patients with Acute Ischemic Stroke Beyond the 6-Hour Window

Background: There is controversy regarding the need to use advanced imaging to select candidates for thrombectomy in late window acute ischemic stroke (AIS). Hypoattenuation on CT angiography source images (CTA-SI) in arterial phase has been shown to be more sensitive than Alberta Stroke Program Early CT score (ASPECTS) of brain parenchyma to determine tissue at risk of ischemia. Our hypothesis is that the addition of a second acquisition at 35-50 seconds could complement the assessment of hypoperfused tissue that fails to receive flow through pial vessels. Methods: Patients with large vessel occlusion and 6-16 hours from symptom onset, admitted between August 2019 and July 2022 were evaluated with dual-phase CT angiography (CTA) and CT-perfusion. The association between automated CT-perfusion values and dual-phase CTA was assessed through a correlation coefficient. Results: Pearson's coefficient demonstrated a high correlation between ischemic core volume and delayed CTA-SI with an inverse association of -0.91 and between Tmax≥6 sec volume and arterial CTA-SI with a value of -0.83. Conclusion: CTA-derived source images (CTA-SI) in two phases may be useful in the selection of patients with AIS presenting beyond the 6-hour window.

Alberta Stroke Program Early CT Score can Predict Severity of Spasticity and Functional Outcome in Ischemic Stroke Survivors.

Post-stroke spasticity is common and an early predictor of the severity of spasticity can help track recovery trajectory helping to modify rehabilitation plans. We explored the utility of the Alberta Stroke Program Early CT Score (ASPECTS) to predict functional motor capacity in patients after acute ischemic stroke. One hundred and one patients (mean age of 58.6 ± 7.6 years; M:F = 72: 29) with the first documented acute ischemic stroke were followed up for three to twelve months after the stroke. Cerebral lesions within the territory of the middle cerebral artery were evaluated using the ASPECTS. Spasticity was assessed using the Modified Ashworth Score (MAS) and walking with Timed Up and Go test (TUG). The associations between severity of spasticity and size/extent of infarct as derived from ASPECTS and between spasticity and functional walking in post-stroke survivors were analyzed. Among the patients studied, 61.3% (n = 62) had infarct in the region of supply of the left middle cerebral artery (MCA) and 38.7% (n = 39) had infarct in the region supplied by the right MCA. Three percent (n = 3) had a low ASPECTS, 53.6% (n = 54) had an intermediate score and 44.4% (n = 44) had a high score. The majority of patients with no to mild spasticity had high ASPECTS. Worse spasticity was significantly associated with low ASPECTS (P = 0.001). High scores in Timed Up and Go test (TUG) were associated with low ASPECTS (P < 0.001). Patients with high ASPECTS had the propensity to have subcortical infarcts (P < 0.001) when compared to those with moderate ASPECTS, who had a mix of cortical and subcortical infarcts. ASPECTS at admission in patients with acute ischemic stroke is a good predictor of post-stroke spasticity and functional walking. Low ASPECTS is associated with higher spasticity and lower functional walking status on follow-up after stroke.

Prediction of Occurrence of Cerebral Infarction After Successful Mechanical Thrombectomy for Ischemic Stroke in the Anterior Circulation by Arterial Spin Labeling

PurposeThe overall goal of our study is to create modified Alberta Stroke Program Early Computed Tomography Score (ASPECTS) determined by the findings on arterial spin labeling imaging (ASL) to predict the prognosis of patients with acute ischemic stroke after successful mechanical thrombectomy (MT). Prior to that, we examined predictive factors including the value of cerebral blood flow (CBF) measured by ASL for occurrence of cerebral infarction at the region of interest (ROI) used in the ASPECTS after successful MT.MethodsOf the 92 consecutive patients with acute ischemic stroke treated with MT at our institution between April 2013 and April 2021, a total of 26 patients who arrived within 8 h after stroke onset and underwent MT resulting in a thrombolysis in cerebral infarction score of 2B or 3 were analyzed. Magnetic resonance imaging, including diffusion-weighted imaging (DWI) and ASL, was performed on arrival and the day after MT. The asymmetry index (AI) of CBF by ASL (ASL-CBF) before MT was calculated for 11 regions of interest using the DWI-Alberta Stroke Program Early CT Score.ResultsOccurrence of infarction after successful MT for ischemic stroke in the anterior circulation can be expected when the formula 0.3211 × history of atrial fibrillation +0.0096 × the AI of ASL-CBF before MT (%) +0.0012 × the time from onset to reperfusion (min) yields a value below 1.0 or when the AI of ASL-CBF before MT is below 61.5%.ConclusionThe AI of ASL-CBF before MT or a combination of a history of atrial fibrillation, the AI of ASL-CBF before MT, and the time from onset to reperfusion can be used to predict the occurrence of infarction in patients arriving within 8 h after stroke onset in which reperfusion with MT was successful.