ASPECTS-Region-Dependent Functional Outcomes after Endovascular Therapy in Patients with Cardioembolic Stroke

Clinical value of automated volumetric quantification of early ischemic tissue changes on non-contrast CT

BACKGROUND

Quantitative and automated volumetric evaluation of early ischemic changes on non-contrast CT (NCCT) has recently been proposed as a new tool to improve prognostic performance in patients undergoing endovascular therapy (EVT) for acute ischemic stroke (AIS). We aimed to test its clinical value compared with the Alberta Stroke Program Early CT Score (ASPECTS) in a large single-institutional patient cohort.

METHODS

A total of 1103 patients with AIS due to large vessel occlusion in the M1 or proximal M2 segments who underwent NCCT and EVT between January 2013 and November 2019 were retrospectively enrolled. Acute ischemic volumes (AIV) and ASPECTS were generated from the baseline NCCT through e-ASPECTS (Brainomix). Correlations were tested using Spearman's coefficient. The predictive capabilities of AIV for a favorable outcome (modified Rankin Scale score at 90 days ≤2) were tested using multivariable logistic regression as well as machine-learning models. Performance of the models was assessed using receiver operating characteristic (ROC) curves and differences were tested using DeLong's test.

RESULTS

Patients with a favorable outcome had a significantly lower AIV (median 12.0 mL (IQR 5.7-21.7) vs 18.8 mL (IQR 9.4-33.9), p<0.001). AIV was highly correlated with ASPECTS (rho=0.78, p<0.001) and weakly correlated with the National Institutes of Health Stroke Scale score at baseline (rho=0.22, p<0.001), and was an independent predictor of an unfavorable clinical outcome (adjusted OR 0.97, 95% CI 0.96 to 0.98). No significant difference was found between machine-learning models using either AIV or ASPECTS or both metrics for predicting a good clinical outcome (p>0.05).

CONCLUSION

AIV is an independent predictor of clinical outcome and presented a non-inferior performance compared with ASPECTS, without clear advantages for prognostic modelling.

Association of Lesion Topography with Functional Outcomes in Acute Ischemic Stroke Patients Considered for, or Receiving, Reperfusion Therapy: A Meta-Analysis

Background: The impact of lesion topography (LT), characterised by the Alberta Stroke Programme Early CT Score (ASPECTS), on outcomes after reperfusion therapy in acute ischemic stroke (AIS) is poorly elucidated. We investigated the prognostic accuracy of ASPECTS-based LT assessment and its association with clinical outcomes in AIS patients considered for reperfusion therapy or receiving intravenous thrombolysis (IVT), endovascular thrombectomy (EVT), or none or both. Methods: Studies were identified from PubMed with additional studies added from Google Scholar. The prevalence of individual ASPECTS regions will also be determined. The association of individual ASPECTS regions with the functional outcome at 90 days will be assessed using random-effects modelling for various cut-offs, such as 6, 7 and 8. The association of continuous ASPECTS with the functional outcome at 90 days will also be undertaken. Forest plots of odds ratios (ORs) will be generated. Results: A total of 25 studies have been included in the final analysis, encompassing 11,404 patients. Pooled estimates indicate that the highest prevalence rates were in cases involving the insula and lentiform nucleus. Subgroup analysis for ASPECTS < 6 (OR 6.10; 95% CI 2.50−14.90; p < 0.0001), ASPECTS < 7 (OR 4.58; 95% CI 1.18−17.86; p < 0.0001) and ASPECTS < 8 (OR 2.26; 95% CI 1.32−3.89; p < 0.0001) revealed a significant association with poor functional outcome at 90 days. Decreasing ASPECTS significantly increased the odds of poor functional outcomes at 90 days (SMD −1.15; 95% CI −1.77−−0.52; p < 0.0001). Conclusions: Our meta-analysis demonstrates that decreasing ASPECTS is significantly associated with poor functional outcomes. Individual ASPECTS regions associated with the highest odds of poor functional outcomes were identified. Future studies on the association of LT and clinical outcomes specific to EVT are required.