Noncontrast versus perfusion CT to select endovascular therapy in an extended time window: Systematic review/meta‐analysis

Abstract Background and Purpose The effect of noncontrast CT (NCCT) on the eligibility for endovascular therapy (EVT) in an extended time window remains to be elucidated. We sought to assess the efficacy and safety of NCCT in comparison with CT perfusion (CTP) in selecting patients with acute ischemic stroke (AIS) for EVT 6‐24 hours after onset. Methods PubMed, Embase, and Cochrane libraries were searched from inception to August 31, 2022, to identify all studies reporting 90‐day outcomes of EVT in patients with AIS in an extended time window. A meta‐analysis was performed for the pooled risk ratio (RR) with 95% confidence interval (CI) using a random‐effects model. The primary outcome used to assess efficacy was good functional independence, defined as a modified Rankin Scale score of 0‐2 at 90 days. Secondary outcomes included successful reperfusion, symptomatic intracranial hemorrhage (sICH), and mortality at 90 days. Results We included four nonrandomized studies with a total of 2685 patients. The outcomes of good functional independence at 90 days (RR = 0.98; 95% CI: 0.88‐1.07; I 2 = 0%; p = .62), successful reperfusion (RR = 0.98; 95% CI: 0.93‐1.03; I 2 = 50.5%; p = .11), sICH (RR = 1.11; 95% CI: 0.55‐2.21; I 2 = 49.4%; p = .12), or mortality at 90 days (RR = 1.18; 95% CI: 0.99‐1.40; I 2 = 0%; p = .42) did not differ significantly between the two groups. Conclusions These findings suggest that NCCT is as effective as CTP in selecting patients for EVT in an extended time window.