Background:Patients with acute ischemic stroke (AIS) treated with endovascular thrombectomy (EVT) in the late window (6-24 hours) can be evaluated with computed tomography perfusion (CTP) or with noncontrast computed tomography (NCCT) only. Whether outcomes differ depending on type of imaging selection is unknown. We conducted a systematic review and meta-analysis comparing outcomes between CTP and NCCT for EVT selection in the late therapeutic window.Methods:This study is reported according to the PRISMA 2020 guidelines. A systematic literature review of the English language literature was conducted using Web of Science, Embase, Scopus, and PubMed databases. Papers focusing on late window AIS undergoing EVT imaged via CTP and NCCT were included. Data were pooled using a random-effects model. The primary outcome of interest was rate of functional independence, defined as modified Rankin Scale (mRS) 0-2. Secondary outcomes of interest included rates of successful reperfusion, defined as thrombolysis in cerebral infarction (TICI) 2b-3, mortality, and symptomatic intracranial hemorrhage (sICH).Results:Five studies with 3,384 patients were included in our analysis. There were comparable rates of functional independence (OR= 1.03, 95% CI, 0.87-1.22; P-value= 0.71) and sICH (OR= 1.09, 95% CI, 0.58-2.04; P-value= 0.80) between the two groups. Patients imaged with CTP had higher rates of successful reperfusion (OR= 1.31, 95% CI, 1.05-1.64; P-value= 0.015) and lower rates of mortality (OR= 0.79, 95% CI, 0.65-0.96; P-value= 0.017).Conclusions:Although recovery of functional independence after late window EVT was not more common in patients selected by CTP as compared to patients selected by NCCT only, patients selected by CTP had lower mortality.