Post-stroke ASPECTS predicts outcome after thrombectomy

Purpose Infarct growth and final infarct volume are established outcome modifiers following endovascular thrombectomy (EVT) for patients with large vessel occlusion stroke (LVO). Simple techniques for final infarct volume measurement are lacking, and therefore, we tested whether post-EVT ASPECTS can be used for prognostic evaluation after EVT. Methods Infarct size at baseline was measured in a prospective cohort of patients with LVO that underwent EVT with the ASPECTS score on admission non-contrast CT. Final infarct size was assessed with a post-EVT ASPECTS (ASPECTS-POST) obtained from a follow-up CT 24-72 h post-EVT. The best performing ASPECTS-POST was chosen based on comparisons of different thresholds. Outcome measures included survival rates and modified Rankin Score at 90 days. Results A total of 272 patients were included and 166 of them had an ASPECTS-POST >= 7. ASPECTS-POST >= 7 was associated with increased likelihood of favorable outcome at 90 days (67% vs. 21%,p < 0.001) with sensitivity, specificity, and positive and negative predictive values of 86%, 58%, 61%, and 85%, respectively. On multivariate analysis, ASPECTS-POST >= 7 was found to be a significant modifier of favorable outcome (Odds Ratio [OR] 6.2, 95% confidence intervals [CI] 3.1-12.4) and survival (OR 5.8 95% CI 2.4-14.3). Conclusion ASPECTS can be rapidly and easily obtained from the post-EVT NCCT and ASPECTS-POST >= 7 correlates with good outcome.