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

Abstract

Background and PurposeThe 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.MethodsPubMed, 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.ResultsWe 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; I2 = 0%; p = .62), successful reperfusion (RR = 0.98; 95% CI: 0.93‐1.03; I2 = 50.5%; p = .11), sICH (RR = 1.11; 95% CI: 0.55‐2.21; I2 = 49.4%; p = .12), or mortality at 90 days (RR = 1.18; 95% CI: 0.99‐1.40; I2 = 0%; p = .42) did not differ significantly between the two groups.ConclusionsThese findings suggest that NCCT is as effective as CTP in selecting patients for EVT in an extended time window.

CTP-Defined Large Core Is a Better Predictor of Poor Outcome for Endovascular Treatment Than ASPECTS-Defined Large Core

“…21,22 Recently, there is an increasing trend of using NCCT ASPECTS in selecting patients with EVT beyond 6-hour window, and comparable rates of 90-day functional independence were reported in patients selected by NCCT and CTP. 23,24 In line with these previous findings, we show NCCT ASPECTS and CTP have similar predictive value in detecting poor outcome beyond 6 hours while the former underestimates its presence within 6 hours (Figures 1 and 2). Based on THRACE (Mechanical Thrombectomy After Intravenous Alteplase Versus Alteplase Alone After Stroke) and MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) studies, 25,26 the American Heart Association/American Stroke Association guidelines recommended using NCCT in selecting patients with EVT within 6 hours to avoid over-excluding patients who would benefit from the treatment.…”