Alberta Stroke Program Early CT Research Articles

Thrombectomy in ischemic stroke patients with large core but minor ischemic changes on non-enhanced computed tomography.

The Alberta Stroke Program Early CT Score (ASPECTS) is regularly used to guide patient selection for mechanical thrombectomy (MT). Similarly, penumbral imaging based on computed tomography perfusion (CTP) may serve as neuroimaging tool to guide treatment. Yet, patients with a large ischemic core on CTP may show only minor ischemic changes resulting in a high ASPECTS. We hypothesized twofold: (1) the treatment effect of vessel recanalization in patients with core volume > 50 mL but ASPECTS ⩾ 6 is not different compared to high ASPECTS patients with core volume < 50 mL, and (2) recanalization is associated with core overestimation. We conducted an observational study analyzing ischemic stroke patients consecutively treated with MT after triage by multimodal CT. Functional endpoint was the rate of functional independence at Day 90 defined as modified Rankin Scale (mRS) 0-2. Imaging endpoint was core overestimation, which was considered when CTP-derived core was larger than the final infarct volume assessed on follow-up imaging. Recanalization was evaluated with the extended Thrombolysis in Cerebral Infarction (eTICI) scale. Multivariable logistic regression analysis and propensity score matching (PSM) were used to assess the association of recanalization (eTICI ⩾ 2b) with functional outcome and core overestimation. Of 630 patients with ASPECTS ⩾ 6, 91 patients (14.4%) had a large ischemic core. Following 1:1 PSM, the treatment effect of recanalization was not different in patients with large core and ASPECTS ⩾ 6 (+ 25.8%, 95% CI: 16.3-35.4, p < 0.001) compared to patients with ASPECTS ⩾ 6 and core volume < 50 mL (+ 14.9%, 95% CI: 5.7-24.1, p = 0.002). Recanalization (aOR: 3.46, 95% CI: 1.85-6.47, p < 0.001) and higher core volume (aOR: 1.03, 95% CI: 1.02-1.04, p < 0.001) were significantly associated with core overestimation. In patients with ASPECTS ⩾ 6, core volumes did not significantly modify outcomes following recanalization. Reperfusion and higher core volume were significantly associated with core overestimation which may explain the treatment effect of MT for patients with a large ischemic core but minor ischemic changes on non-enhanced CT. The data analyzed in this study will be available and shared on reasonable request from any qualified researcher for the purpose of replicating the results after clearance by the local ethics committee.

Endovascular treatment versus standard medical treatment in patients with established large infarct: a cohort study.

Previous trials confirmed the benefit of endovascular treatment (EVT) in acute large core stroke, but the effect of EVT on outcomes in these patients based on non-contrast computed tomography (NCCT) in real-world clinical practice was unclear. The aim of this study was to explore the effect of EVT versus standard medical treatment (SMT) in patients with large ischemic core stroke defined as Alberta Stroke Program Early CT Score (ASPECTS)≤5 based on NCCT alone. Patients with acute large core stroke at 38 Chinese centers between November 2021 and February 2023 were reviewed from prospectively maintained databases. The primary outcome was favorable functional outcome (modified Rankin Scale score [mRS], 0-3) at 90 days. Safety outcomes included 48-hour symptomatic intracerebral hemorrhage (sICH) and 90-day mortality. Of 745 eligible patients recruited at 38 stroke centers between November 2021 and February 2023, 490 were treated with EVT and 255 with SMT alone. One hundred and eighty-one (36.9%) in the EVT group achieved favorable functional independence versus 48 (18.8%) treated with SMT only (adjusted risk ratio [RR], 1.86; 95% CI, 1.43 to 2.42, P<0.001; adjusted risk difference [RD], 13.77; 95% CI, 7.40 to 20.15, P<0.001). The proportion of sICH was significantly higher in patients undergoing EVT (13.3% vs. 2.4%; adjusted RR, 5.17; 95% CI, 2.17 to 12.32, P<0.001; adjusted RD, 10.10; 95% CI, 6.12 to 14.09, P<0.001). No significant difference of mortality between the groups was observed (41.8% vs. 49.0%; adjusted RR, 0.91; 95% CI, 0.77 to 1.07, P=0.24; adjusted RD, -5.91; 95% CI, -12.91 to 1.09, P=0.1). Among patients with acute large core stroke based on NCCT in real world, EVT is associated with better functional outcomes at 90 days despite of higher risk of sICH. Rates of procedure-related complications were high in the EVT group.

Three years' interventional neurology experience in Turkey with the Thrombite thrombectomy device in large vessel occlusion in the anterior circulation: safety, efficacy, and clinical outcome.

While the Thrombite device differs from the Solitare stent with its Helical open-side structure feature, it shows great similarity with its other features. We assessed the Thrombite device's effectiveness and safety in this study. The study was a retrospective analysis of patients who were included in the Turkish Interventional Neurology database and who had mechanical thrombectomy with the Thrombite device as the first choice between January 2020 and January 2023. The type of study is descriptive research. Using the Thrombite thrombectomy device, 525 patients received treatment. The median baseline National Institutes of Health Stroke Scale (NIHSS) score was 13, the median initial Alberta Stroke Program Early Computed Tomography (ASPECT) score was 8, and the mean patient age was 68.6+11.7 years. Between the groin puncture and the successful recanalization, the median time was 34 minutes (interquartile range [IQR]: 15-45). 48.2% (modified treatment in cerebral infarction; mTICI) 2b/3% and 33.9% (mTICI 2c/3) were the first-pass recanalization rates. In the end, 87.7% of patients had effective recanalization (thrombolysis in cerebral infarction 2b/3). In the "first-pass" subgroup, the favorable functional result (modified Rankin Scale 0-2) was 51.8%, while it was 41.6% for the entire patient population. The rate of embolization into new territory/different territory were 2.1/0.1%. 23 patients (4.5%) had symptomatic hemorrhage. The Thrombite device showed a good safety profile and high overall successful recanalization rates in our experience.

Importance of computed tomography perfusion on assessing collateral circulation and prognosis of patients with acute anterior circulation large vessel occlusion after endovascular therapy

This study probed the importance of computed tomography perfusion (CTP) on assessing collateral circulation and prognosis in patients with acute anterior circulation large vessel occlusion (AAC-LVO) after endovascular therapy (EVT). Retrospective analysis was performed on the case data of 124 AAC-LVO patients who achieved EVT in the First People's Hospital of Lianyungang. All patients received computed tomography (CT) examination. Based on the multi-phase computed tomography angiography (mCTA) score, patients were separated into poor collateral circulation group and good collateral circulation group. Based on modified Rankin scale (mRS) score, patients were separated into good prognosis group and poor prognosis group. The receiver operating characteristic (ROC) curve was used to measure the efficacy of CTP parameters in predicting good collateral circulation or good prognosis. Correlation between CTP parameters with mCTA collateral and 90-day mRS circulation score was analyzed using the Spearman correlation analysis. The age and admission national Institutes of Health stroke scale (NIHSS) scores of the good collateral circulation group were lower than the poor collateral circulation group, and low perfusion area volume with Tmax > 6 s (VTmax>6s), infarct core area volume (VCBF<30%)and hypoperfusion intensity ratio (HIR) were also lower. The mCTA collateral cycle score was negatively related to VTmax>6 s, VCBF<30% and HIR. The area under the curve (AUC) values of VTmax>6 s and VCBF<30% and HIR for predicting good collateral circulation were 0.763, 0.884 and 0.842, respectively, which suggested that perfusion parameters VTmax>6 s, VCBF<30% and HIR could effectively indicate the status of patients’ collateral circulation. Relative to the poor prognosis group, patients in the good prognosis group possessed lower admission NIHSS score, younger age, smaller final infarct volume, lower HIR, VCBF<30%, VTmax>6s, Alberta Stroke Program Early CT(ASPECT) score, and higher mCTA score. Spearman correlation analysis unveiled that ASPECT score, mCTA score and 90-day mRS were negatively correlated. The final infarct volume, perfusion parameters HIR and VCBF<30% were positively correlated with 90-day mRS. ROC analysis showed that all variates had good prognostic value for acute anterior circulation great vessel occlusion patients, while VCBF<30% and HIR had high diagnostic value for prognosis. To sum up, CTP can provide a comprehensive imaging assessment of the collateral circulation of patients with AAC-LVO and has a higher predictive value for the prognosis assessment of patients with EVT in terms of VCBF<30%, HIR score and mCTA collateral circulation score.

Endovascular Thrombectomy for Large Ischemic Strokes with ASPECTS 0-2: aMeta-analysis of Randomized Controlled Trials.

Randomized controlled trials (RCTs) demonstrated atreatment effect of endovascular thrombectomy in acute ischemic stroke with large infarct, commonly defined as an Alberta Stroke Program Early CT Score (ASPECTS) of 3-5. However, data on endovascular thrombectomy in patients with very low ASPECTS of 0-2 remain scarce. We conducted asystematic review and meta-analysis of RCTs comparing endovascular thrombectomy versus medical treatment alone in acute ischemic anterior circulation stroke with very large infarct, defined as ASPECTS of 0-2. The primary outcome was the shift toward better functional outcomes on the 90-day modified Rankin Scale (mRS). Random effects meta-analysis was performed using the generic inverse variance method. Literature research identified four RCTs which evaluated the treatment effect of endovascular thrombectomy for large infarcts and provided asubgroup analysis of the mRS shift in patients with ASPECTS of 0-2. The pooled analysis showed asignificant shift toward better 90-day mRS scores in favor of endovascular thrombectomy (pooled odds ratio, 1.62, 95% confidence interval, 1.29-2.04, P < 0.001). This meta-analysis suggests atreatment effect of endovascular thrombectomy in specific patients with very low ASPECTS of 0-2, challenging the use of ASPECTS for treatment selection in acute ischemic stroke due to large vessel occlusion. An individual patient meta-analysis of RCTs would strengthen evidence in the treatment of patients with ASPECTS of 0-2.

Long term outcome after endovascular treatment for large ischemic core acute stroke is associated with hypoperfusion intensity ratio and onset-to-reperfusion time.

Endovascular treatment (EVT) is effective for large vessel occlusion (LVO) stroke with smaller volumes of CT perfusion (CTP)-defined core. However, the influence of perfusion imaging during thrombectomy on the functional outcomes of patients with large ischemic core (LIC) stroke at both early and late time windows is uncertain in real-world practice. A retrospective analysis was performed on 99 patients who underwent computed tomography angiography (CTA) and CT perfusion (CTP)-Rapid Processing of Perfusion and Diffusion (RAPID) before EVT and had a baseline ischemic core ≥ 50 mL and/or Alberta Stroke Program Early CT Score (ASPECTS) score of 0-5. The primary outcome was the three-month modified Rankin Scale (mRS) score. Data were analyzed by binary logistic regression and receiver operating characteristic (ROC) curves. A fair outcome (mRS, 0-3) was found in 34 of the 99 patients while 65 had a poor prognosis (mRS, 4-6). The multivariate logistic regression analysis showed that onset-to-reperfusion (OTR) time (odds ratio [OR], 1.004; 95% confidence interval [CI], 1.001-1.007; p = 0.008), ischemic core (OR, 1.066; 95% CI, 1.024-1.111; p = 0.008), and the hypoperfusion intensity ratio (HIR) (OR, 70.898; 95% CI, 1.130-4450.152; p = 0.044) were independent predictors of outcome. The combined results of ischemic core, HIR, and OTR time showed good performance with an area under the ROC curve (AUC) of 0.937, significantly higher than the individual variables (p < 0.05) using DeLong's test. Higher HIR and longer OTR time in large core stroke patients were independently associated with unfavorable three-month outcomes after EVT.

HEMERA‐1 CarboxyHEMoglobin OxygEn Delivery for Evascularization in Acute Stroke: A Prospective, Randomized Phase 1 Clinical Trial

BACKGROUND PP‐007 is a polyethylene glycol (PEG)ylated bovine carboxyhemoglobin gas transfer molecule with pleotropic cytoprotective effects, vasodilatation, plasma expansion, and optimization of oxygen delivery. Rodent middle cerebral artery occlusion models have demonstrated that PP‐007 increases blood flow in the collateral circulation and reduces final infarct volumes, supporting a potential role as neuroprotective agent in acute ischemic stroke. We aim to evaluate the safety and feasibility of PP‐007 as an adjunctive treatment to mechanical thrombectomy (MT) in patients with stroke secondary to large vessel occlusion. METHODS HEMERA‐1 (CarboxyHEMoglobin OxygEn delivery for Revascularization in Acute Stroke) was a multicenter, prospective, randomized, controlled phase 1 clinical trial. Anterior circulation large vessel occlusion patients were assigned in a 3:1 ratio to receive either PP‐007 (320 mg/kg: 30 min bolus followed by 2‐h infusion) plus MT or MT alone within 24 hours after symptom onset. Comprehensive safety evaluation was performed by independent Data Monitoring Safety Board and Imaging Core Lab. RESULTS From October 1, 2021 to June 30, 2022, a total of 17 patients were recruited. Age, baseline National Institutes of Health Stroke Scale score, and Alberta Stroke Program Early CT Score were 74.8±12.7 years, 17.3±4.2, and 7.9±1.8, respectively. Twelve patients were randomized to PP‐007 plus MT, 1 was randomized but not treated, 4 patients were randomized to MT alone. Recanalization of the occluded vessel was achieved in all patients. A transient systolic blood pressure increase (20–40 mm Hg) during the bolus was observed in all PP‐007 patients without any clinical consequences. There were no other safety concerns. CONCLUSION No significant safety concerns were identified for the adjunctive use of PP‐007 in patients undergoing MT. (The study was funded by Prolong Pharmaceuticals. REGISTRATION URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04677777.

Serial ASPECTS to predict stroke-associated pneumonia after thrombolysis in patients with acute ischemic stroke.

Stroke-associated pneumonia (SAP) is a serious complication in stroke patients, significantly increasing mortality. The Alberta Stroke Program Early CT Score (ASPECTS) is a recognized predictor of acute ischemic stroke outcomes. We aimed to investigate the performance of serial ASPECTS assessments (baseline ASPECTS, 24-h ASPECTS, and change in ASPECTS) for predicting SAP in patients with thrombolyzed acute anterior circulation ischemic stroke (AACIS). A retrospective observational cohort study of adult patients with thrombolyzed AACIS was conducted. Baseline and 24-h ASPECTS using non-contrast computed tomography (NCCT), complications of stroke, including SAP and swallowing dysfunction using the Modified Water Swallowing test, were collected. Baseline and 24-h ASPECTS were evaluated by a certified neurologist and neuroradiologist. The predictive performance was determined based on the receiver operating characteristic curve (ROC). Multivariable logistic regression analyses were employed to assess the impact of serial ASPECTS assessment on predicting SAP. Of the 345 patients with thrombolyzed AACIS in our study, 18.4% (64/345) experienced SAP. The patients' median age was 62 years [interquartile range (IQR): 52-73], with 53.4% being male. The median NIHSS score was 11 points (IQR: 8-17). The ROC analysis revealed areas under the curve for predicting SAP with baseline ASPECTS, 24-h ASPECTS, and change in ASPECTS were 0.75 (95% CI, 0.69-0.82), 0.84 (95% CI, 0.79-0.89), and 0.82 (95% CI, 0.76-0.87), respectively. Of the three measures, 24-h ASPECTS was a better predictor of SAP (odds ratio: 5.33, 95%CI: 2.08-13.67, p < 0.001) and had a higher sensitivity (0.84 [95%CI, 0.74-0.92]) and specificity (0.79 [95%CI, 0.74-0.84]) than both baseline ASPECTS and change in ASPECTS. 24-h NCCT-ASPECTS outperformed both baseline ASPECTS and change in ASPECTS for predicting SAP. Notably, 24-h ASPECTS, with a cut-off value of ≤6, exhibited good predictive performance and emerged as the better predictor for SAP.

The use of thromboaspiration and combined treatment in patients with ischemic stroke in real-life clinical practice

The effectiveness of staged reperfusion therapy in real clinical practice requires clarification. Objective: to evaluate the efficacy and safety of mechanical thromboextraction and staged reperfusion therapy with alteplase in real clinical practice. Material and methods. The study included 106 patients who were retrospectively divided into two groups: Group I underwent staged reperfusion therapy (intravenous thrombolysis with alteplase followed by aspiration thromboextraction), Group II underwent thromboaspiration only. The clinical and functional results, incidence of hemorrhagic transformation and mortality rate were compared. Results. The groups did not differ in terms of demographic data, cardiovascular risk factors or stroke severity. Group II patients were characterized by a longer delay in reperfusion therapy (225 minutes versus 180 minutes) and a lower score on the Alberta Stroke Programme Early CT score (ASPECTS; 8.8 points versus 9.3 points). There were no differences in National Institutes of Health Stroke Scale (NIHSS) scores at day 28, dynamics of NIHSS scores, Rankin scores at day 28, rates of hemorrhagic transformation or mortality. In both groups, the deceased patients were older; in Group I they suffered more frequently from atrial fibrillation, in Group II – from diabetes mellitus type 2. In addition, mortality in Group II was associated with a higher severity of early signs of cerebral infarction.Conclusion. The results of the analysis of real-life clinical practice show the comparability of the efficacy and safety of staged reperfusion therapy and isolated thromboaspiration in a “natural” selection of patients.

The role of blood protein biomarkers in acute ischemic stroke prognosis

BackgroundStroke is one of the most frequent causes of mortality and disability, blood protein biomarkers are used to determine patients at high risk for a severe illness and to estimate the outcome. This study aimed to detect the relation between serum levels of C-reactive protein, matrix metalloproteinase 9, S100 calcium-binding protein B, brain natriuretic peptide, D-dimer and stroke severity and outcome in acute ischemic stroke patients.ResultsOne hundred eighty-six patients with acute ischemic stroke participated and were subjected to complete general, neurological examination, assessment of stroke severity clinically and radiologically using National Institute of Health Stroke Scale (NIHSS), and Alberta Stroke Program Early CT (ASPECT) score and assessment of functional outcome using (modified Rankin Scale). C-reactive protein, matrix metalloproteinase 9, S100 calcium-binding protein B, brain natriuretic peptide and D-dimer were assessed. Higher C-reactive protein was found in patients with ASPECT score ≤ 7 and in patients with cerebral edema, seizures and was positively correlated with stroke severity according to NIHSS and modified Rankin Scale. C-reactive protein serum level at onset was negatively correlated with NIHSS at onset and is a significant predictor for mortality. D-dimer was negatively correlated with NIHSS. S100 calcium-binding protein B was significantly elevated in patients who developed hemorrhagic transformation.ConclusionsSerum C-reactive protein level can be used as a predictor for mortality and higher S100 calcium-binding protein B was detected in patients with hemorrhagic transformation.

Does the Ischemic Core Really Matter? An Updated Systematic Review and Meta‐Analysis of Large Core Trials After TESLA, TENSION, and LASTE

Background The available evidence supporting the use of endovascular thrombectomy (EVT) in acute ischemic stroke patients with large core has increased with the recent release of the Thrombectomy for Emergent Salvage of Large Anterior Circulation Ischemic Stroke (TESLA), Efficacy and Safety of Thrombectomy In Stroke with Extended Lesion and Extended Time Window (TENSION), and Large Stroke Therapy Evaluation (LASTE) trials, providing critical information on additional subgroups not included in initial trials. We aimed to study the efficacy and safety of EVT in patients with acute ischemic stroke with large core and stratify by several subgroups including core infarct at presentation, using a comprehensive meta‐analysis of aggregate data. Methods We executed a systematic search to identify randomized controlled trials that compared EVT to medical management (MM) for the treatment of patients with acute ischemic stroke with large core, defined as Alberta Stroke Program Early CT [Computed Tomography] Score ≤5 on noncontrast CT and/or estimated ischemic core ≥50 mL on CT‐perfusion/MR diffusion. The primary outcome was the shift analysis in the 90‐day modified Rankin scale (mRS) score. Secondary outcomes included functional independence (mRS score 0–2), independent ambulation (mRS score 0–3), 90‐day mortality, and symptomatic intracranial hemorrhage. Pooled odds ratios were calculated for shift mRS score through the random‐effects meta‐analyses, and risk ratios (RRs) were used for the other outcomes, comparing EVT with MM alone. Results Out of 3402 titles and abstracts screened, 6 randomized controlled trials with 1886 patients were included. The EVT group had a higher shift toward a lower mRS than MM alone (odds ratio [OR], 1.49 [95% CI, 1.24–1.79]). Furthermore, the use of EVT was associated with higher rates of functional independence (19.5% versus 7.5%, RR, 2.49 [95% CI, 1.92–3.24]), independent ambulation (36.5% versus 19.9%, RR, 1.91 [95% CI, 1.51–2.43]), and symptomatic intracranial hemorrhage (5.5% versus 3.2%, RR, 1.73 [95% CI, 1.01–2.95]) compared with MM. There was no difference between the 2 groups regarding mortality (31.5% versus 36.8%, RR, 0.86 [95% CI, 0.72–1.02]). Importantly, EVT was consistently associated with a shift toward a lower mRS score in both Alberta Stroke Program Early CT Score 3–5 (OR, 1.60 [95% CI, 1.10–2.32]) and Alberta Stroke Program Early CT Score 0–2 (OR, 1.45 [95% CI, 1.17–1.80]) when compared with MM alone. Conclusion Our results confirm the efficacy of EVT for acute ischemic stroke with large core and suggest a consistent benefit across all Alberta Stroke Program Early CT Score categories. These results represent an important shift in the current large vessel occlusion selection paradigm that currently considers core as an effect modifier for EVT selection.

Association of clinical outcome and imaging endpoints in extensive ischemic stroke—comparing measures of cerebral edema

Abstract Objectives Ischemic edema is associated with worse clinical outcomes, especially in large infarcts. Computed tomography (CT)–based densitometry allows direct quantification of absolute edema volume (EV), which challenges indirect biomarkers like midline shift (MLS). We compared EV and MLS as imaging biomarkers of ischemic edema and predictors of malignant infarction (MI) and very poor clinical outcome (VPCO) in early follow-up CT of patients with large infarcts. Materials and methods Patients with anterior circulation stroke, large vessel occlusion, and Alberta Stroke Program Early CT Score (ASPECTS) ≤ 5 were included. VPCO was defined as modified Rankin scale (mRS) ≥ 5 at discharge. MLS and EV were quantified at admission and in follow-up CT 24 h after admission. Correlation was analyzed between MLS, EV, and total infarct volume (TIV). Multivariable logistic regression and receiver operating characteristics curve analyses were performed to compare MLS and EV as predictors of MI and VPCO. Results Seventy patients (median TIV 110 mL) were analyzed. EV showed strong correlation to TIV (r = 0.91, p &lt; 0.001) and good diagnostic accuracy to classify MI (EV AUC 0.74 [95%CI 0.61–0.88] vs. MLS AUC 0.82 [95%CI 0.71–0.94]; p = 0.48) and VPCO (EV AUC 0.72 [95%CI 0.60–0.84] vs. MLS AUC 0.69 [95%CI 0.57–0.81]; p = 0.5) with no significant difference compared to MLS, which did not correlate with TIV &lt; 110 mL (r = 0.17, p = 0.33). Conclusion EV might serve as an imaging biomarker of ischemic edema in future studies, as it is applicable to infarcts of all volumes and predicts MI and VPCO in patients with large infarcts with the same accuracy as MLS. Clinical relevance statement Utilization of edema volume instead of midline shift as an edema parameter would allow differentiation of patients with large and small infarcts based on the extent of edema, with possible advantages in the prediction of treatment effects, complications, and outcome. Key Points • CT densitometry–based absolute edema volume challenges midline shift as current gold standard measure of ischemic edema. • Edema volume predicts malignant infarction and poor clinical outcome in patients with large infarcts with similar accuracy compared to MLS irrespective of the lesion extent. • Edema volume might serve as a reliable quantitative imaging biomarker of ischemic edema in acute stroke triage independent of lesion size.

Baseline clinical and neuroradiological predictors of outcome in patients with large ischemic core undergoing mechanical thrombectomy: A retrospective multicenter study.

Recent randomized trials have shown the benefit of mechanical thrombectomy (MT) also in patients with an established large ischemic core. The purpose of this study was to define baseline predictors of clinical outcome in patients with large vessel occlusion (LVO) in the anterior circulation and an Alberta Stroke Program Early CT score (ASPECTS) ⩽ 5, undergoing MT. The databases of 16 comprehensive stroke centers were retrospectively screened for patients with LVO and ASPECTS ⩽5 that received MT. Baseline clinical and neuroradiological features, including the differential contribution of all ASPECTS regions to the composite score, were collected. Primary clinical outcome measure was a 90-day modified Rankin Scale (mRS) score of 0-2. Statistical analysis used a logistic regression model and random forest algorithm. A total of 408 patients were available for analysis. In multivariate model, among baseline features, lower age (odd ratio (OR) = 0.962, 95% confidence interval (CI) = 0.943-0.982) and lower National Institute of Health Stroke Scale (NIHSS) score (OR = 0.911, 95% CI = 0.862-0.963) were associated with the mRS score 0-2. Involvement of the M2 (OR = 0.398, 95% CI = 0.206-0.770) or M4 (OR = 0.496, 95% CI = 0.260-0.945) ASPECTS regions was associated with an unfavorable outcome. Random forest analysis confirmed that age and baseline NIHSS score are the most important variables influencing clinical outcome, whereas involvement of cortical regions M5, M4, M2, and M1 can have a negative impact. Our retrospective analysis shows that, along with age and baseline clinical impairment, presence of early ischemic changes involving cortical areas has a role in clinical outcome in patients with large ischemic core undergoing MT. The data that support the findings of this study are available upon reasonable request.

Outcomes of endovascular thrombectomy for ischaemic stroke among nonagenarians with and without pre-existing dependency

BackgroundOur aim was to compare the outcomes of treatment with endovascular thrombectomy for pre-stroke dependent versus pre-stroke independent among the very elderly ≥90 years. MethodsA retrospective cohort study was performed on 106 patients ≥90 years who underwent endovascular thrombectomy for ischaemic stroke in Western Australia between June 2016 and September 2021. Patient, stroke and procedural details along with inpatient progress and outcome at 90 days were recorded. Patients were divided into Group A (pre-stroke modified Rankin Scale 0-2) and Group B (pre-stroke modified Rankin Scale >2). Primary outcome measure was functional status at 90 days post-stroke, with favourable clinical outcome defined as a 90-day mRS category equal to the patients’ respective pre-stroke mRS category. Secondary outcome measures include successful reperfusion, symptomatic intracranial haemorrhage, hospital length-of-stay, change in accommodation to an aged care facility, and mortality during admission, at 90 days and one year. Results61 patients were allocated to Group A and 45 to Group B. There was none with pre-stroke mRS 5. Group B had more pre-existing cognitive impairment, aged care facility residents, higher median age and lower Alberta Stroke Program Early CT Score. For primary outcome measure, 38 % of patients in Group A and 49 % in Group B achieved a favourable clinical outcome. The difference was not significant (p=0.3408). For secondary outcome measures, Group B had a significantly higher 90-day mortality rate at 47 % versus 24 % in Group A (p=0.03). All other secondary outcome measures were similar between the two groups. These include the rate of successful reperfusion and symptomatic intracranial haemorrhage, hospital length-of-stay, new transition into an aged care facility, inpatient mortality rate and 1-year mortality rate. ConclusionWhen treated with endovascular thrombectomy for ischaemic stroke, nonagenarians with pre-existing dependency achieved a rate of favourable functional outcome comparable with their independent peers, although they also had higher 90-day mortality rate.

Application of imaging modalities for endovascular thrombectomy of large core infarcts in clinical practice.

Four randomized controlled trials of large infarct core volume (LICV) included three imaging modalities: non-contrast CT (NCCT)-Alberta Stroke Program Early CT Score (ASPECTS), diffusion-weighted imaging (DWI)-ASPECTS, and NCCT-ASPECTS combined with CTP (CT perfusion). However, there is no clear consensus on the optimal imaging modality for endovascular thrombectomy (EVT) trials of large core infarcts. The variety and complexity of imaging modalities make it difficult to apply them in clinical practice. By familiarizing ourselves with these imaging modalities, we can better apply them in the clinic and correctly screen patients with large core infarcts in the anterior circulation who can benefit from EVT therapy.

Assessing variability in non-contrast CT for the evaluation of stroke: The effect of CT image reconstruction conditions on AI-based CAD measurements of ASPECTS value and hypodense volume.

To rule out hemorrhage, non-contrast CT (NCCT) scans are used for early evaluation of patients with suspected stroke. Recently, artificial intelligence tools have been developed to assist with determining eligibility for reperfusion therapies by automating measurement of the Alberta Stroke Program Early CT Score (ASPECTS), a 10-point scale with > 7 or ≤ 7 being a threshold for change in functional outcome prediction and higher chance of symptomatic hemorrhage, and hypodense volume. The purpose of this work was to investigate the effects of CT reconstruction kernel and slice thickness on ASPECTS and hypodense volume. The NCCT series image data of 87 patients imaged with a CT stroke protocol at our institution were reconstructed with 3 kernels (H10s-smooth, H40s-medium, H70h-sharp) and 2 slice thicknesses (1.5mm and 5mm) to create a reference condition (H40s/5mm) and 5 non-reference conditions. Each reconstruction for each patient was analyzed with the Brainomix e-Stroke software (Brainomix, Oxford, England) which yields an ASPECTS value and measure of total hypodense volume (mL). An ASPECTS value was returned for 74 of 87 cases in the reference condition (13 failures). ASPECTS in non-reference conditions changed from that measured in the reference condition for 59 cases, 7 of which changed above or below the clinical threshold of 7 for 3 non-reference conditions. ANOVA tests were performed to compare the differences in protocols, Dunnett's post-hoc tests were performed after ANOVA, and a significance level of p < 0.05 was defined. There was no significant effect of kernel (p = 0.91), a significant effect of slice thickness (p < 0.01) and no significant interaction between these factors (p = 0.91). Post-hoc tests indicated no significant difference between ASPECTS estimated in the reference and any non-reference conditions. There was a significant effect of kernel (p < 0.01) and slice thickness (p < 0.01) on hypodense volume, however there was no significant interaction between these factors (p = 0.79). Post-hoc tests indicated significantly different hypodense volume measurements for H10s/1.5mm (p = 0.03), H40s/1.5mm (p < 0.01), H70h/5mm (p < 0.01). No significant difference was found in hypodense volume measured in the H10s/5mm condition (p = 0.96). Automated ASPECTS and hypodense volume measurements can be significantly impacted by reconstruction kernel and slice thickness.

Impact of immediate postrecanalization cooling on outcome in acute ischemic stroke patients with a large ischemic core: prospective cohort study.

Patients with large acute ischemic strokes (AIS) often have a poor prognosis despite successful recanalization due to multiple factors including reperfusion injury. The authors aim to describe our preliminary experience of endovascular cooling in patients with a large AIS after recanalization. From January 2021 to July 2022, AIS patients presenting with large infarcts (defined as ASPECTS ≤5 on noncontrast CT or ischemic core ≥50ml on CT perfusion) who achieved successful recanalization after endovascular treatment were analyzed in a prospective registry. Patients were divided into targeted temperature management (TTM) and non-TTM group. Patients in the TTM group received systemic cooling with a targeted core temperature of 33° for at least 48h. The primary outcome is 90-day favorable outcome [modified Rankin Scale (mRS) 0-2]. The secondary outcomes are 90-day good outcome (mRS 0-3), mortality, intracranial hemorrhage and malignant cerebral edema within 7 days or at discharge. Forty-four AIS patients were recruited (15 cases in the TTM group and 29 cases in the non-TTM group). The median Alberta Stroke Program Early CT Score (ASPECTS) was 3 (2-5). The median time for hypothermia duration was 84 (71.5-147.6) h. The TTM group had a numerically higher proportion of 90-day favorable outcomes than the non-TTM group (46.7 vs. 27.6%, P=0.210), and no significant difference were found regarding secondary outcomes (all P>0.05). The TTM group had a numerically higher rates of pneumonia (66.7 vs. 58.6%, P=0.604) and deep vein thrombosis (33.3 vs. 13.8%, P=0.138). Shivering occurred in 4/15 (26.7%) of the TTM patients and in none of the non-TTM patients (P=0.009). Postrecanalization cooling is feasible in patients with a large ischemic core. Future randomized clinical trials are warranted to validate its efficacy.

Alberta Stroke Program Early CT Score 활용한 급성 및 만성 뇌경색 차이 분석

This study aimed to analyze the effect of CT images including old infarction on the Alberta stroke program early CT score (ASPECTS) for acute stroke diagnosis. Location of acute and old infarction through automatically calculated ASPECTS and diffusion weighted image interpretation of patients who have undergone both CT scan and diffusion weighted image MRI for acute stroke diagnosis among patients with suspected cerebral infarction who visited the emergency room After comparison, it was determined whether the location of old infarction had an effect on ASPECTS. The Pearson chi-square test was analyzed for the ASPECT score according to the presence or absence of cerebral infarction, and SPSS version 28.0 was used as the analysis program, and it was judged to be significant when the P value was less than 0.05. As a result of this study, in the analysis of whether old infarction affects ASPECTS, chronic cerebral infarction showed an effect on ASPECTS in the group divided into 10, 9, 8, and 7 points or less, and the group divided into 10 and 9 points. However, in the analysis of the groups with scores of 9, 8, and 7 or less, excluding 10, and the group divided into 8 or more and 7 or less, old infarction did not show any effect on ASPECTS. In conclusion, it is believed that complementary research is needed to diagnose acute stroke and predict prognosis in patients with various brain diseases using an improved artificial intelligence program through large-scale research in ASPECTS.

Combined effect of ASPECTS and age on outcome of patients with large core infarction treated with mechanical thrombectomy

BackgroundDespite the remarkable effectiveness of endovascular treatment (EVT), recent randomized controlled trials indicate that up to half of patients with large core infarction have a very poor outcome (modified Rankin...

Functional Outcomes and Symptomatic Intracranial Hemorrhage After Endovascular Treatment in Acute Vertebrobasilar Artery Occlusions: External Validation of Prediction Models

Background Vertebrobasilar artery occlusion (VBAO) is a severe type of stroke. Multiple prediction models for outcome and symptomatic intracranial hemorrhage (sICH) of patients with acute ischemic stroke treated with endovascular treatment have been developed to improve patient management, but few are based on VBAO. This study aimed to provide an overview of published models to predict functional outcome and sICH as well as to validate their ability in patients with acute VBAO treated with endovascular treatment. Methods We performed a systematic search to identify models either developed or validated to predict functional outcomes or sICH after endovascular treatment. Models were externally validated in the Posterior Circulation Ischemic Stroke Registry (PERSIST) study (n = 2422). Outcome measures included the modified Rankin Scale (mRS) score at 90 days and sICH. Model performance was evaluated with discrimination (c‐statistic) and calibration (slope and intercept). Results A total of 65 models were included in overview. The most frequently used predictors were baseline National Institutes of Health Stroke Scale score (n = 57), age (n = 45), and glucose (n = 32). In the external validation cohort, 777 of 2353 patients (33.0%) achieved mRS score 0–2 at 90 days, 1061 of 2353 patients (45.1%) patients achieved mRS score 0–3 at 90 days, and sICH occurred in 170 of 2422 patients (7.0%). Finally, 27 models were included in external validation. For functional outcome models focusing on mRS score 0–2/3–6, discrimination ranged from 0.63 to 0.66 and best calibrated model was SC (Stroke Checkerboard) (intercept, −0.13 [95% CI, −0.27 to 0.01]; slope, 0.92 [95% CI, 0.67–1.17]). For functional outcome models focusing on mRS score 0–3/4–6, discrimination ranged from 0.64 to 0.74 and best calibrated model was modified Houston Intra‐Arterial Therapy 2 (mHIAT2) (intercept, −0.12 [95% CI, −0.31 to 0.07]; slope, 0.85 [95% CI, 0.65–1.04]). For sICH models, discrimination ranged from 0.53 to 0.83 and best calibrated model was Thrombolysis in Cerebral Infarction score, Alberta Stroke Program Early CT Score, and glucose (TAG) (intercept, 0.13 [95% CI, −0.25 to 0.51]; slope, 0.93 [95% CI, 0.63–1.23]). Conclusions The currently published models are inadequate for predicting functional outcomes and sICH in patients with acute VBAO undergoing endovascular treatment and, therefore, there is a need for more effective models specifically developed for VBAO conditions.