Perfusion-Based Selection for Endovascular Reperfusion Therapy in Anterior Circulation Acute Ischemic Stroke

BACKGROUND AND PURPOSE:Controversy exists about the role of perfusion imaging in patient selection for endovascular reperfusion therapy in acute ischemic stroke. We hypothesized that perfusion imaging versus noncontrast CT- based selection would be associated with improved functional outcomes at 3 months.MATERIALS AND METHODS:We reviewed consecutive patients with anterior circulation strokes treated with endovascular reperfusion therapy within 8 hours and with baseline NIHSS score of ≥8. Baseline clinical data, selection mode (perfusion versus NCCT), angiographic data, complications, and modified Rankin Scale score at 3 months were collected. Using multivariable logistic regression, we assessed whether the mode of selection for endovascular reperfusion therapy (perfusion-based versus NCCT-based) was independently associated with good outcome.RESULTS:Two-hundred fourteen patients (mean age, 67.2 years; median NIHSS score, 18; MCA occlusion 74% and ICA occlusion 26%) were included. Perfusion imaging was used in 76 (35.5%) patients (39 CT and 37 MR imaging). Perfusion imaging–selected patients were more likely to have good outcomes compared with NCCT-selected patients (55.3 versus 33.3%, P = .002); perfusion selection by CT was associated with similar outcomes as that by MR imaging (CTP, 56.; MR perfusion, 54.1%; P = .836). In multivariable analysis, CT or MR perfusion imaging selection remained strongly associated with good outcome (adjusted OR, 2.34; 95% CI, 1.22–4.47), independent of baseline severity and reperfusion.CONCLUSIONS:In this multicenter study, patients with acute ischemic stroke who underwent perfusion imaging were more than 2-fold more likely to have good outcomes following endovascular reperfusion therapy. Randomized studies should compare perfusion imaging with NCCT imaging for patient selection for endovascular reperfusion therapy.

Endovascular reperfusion therapy (ERT) for acute ischemic stroke has been associated with mixed results. In trials of carefully selected patients with middle cerebral artery occlusion, a benefit of intra-arterial thrombolysis over placebo was seen when patients were treated within 6 hours.^1,2 However, subsequent single-arm studies of mechanical embolectomy have observed less impressive results^3,4 and suggest that outcomes are related to several key factors, including patient characteristics (age, co-morbidities, and stroke severity) and treatment factors (time to reperfusion).^5–10 Radiographic features, including pretreatment tissue status by NCCT of the head, brain MR imaging, and perfusion imaging (CTP or MR perfusion [MRP]), may improve patient selection.^5,8,9,11 Few studies have compared NCCT-based selection with perfusion imaging–based selection of patients for ERT following acute ischemic stroke.^12,13 We, therefore, sought to compare NCCT selection with perfusion imaging selection as a predictor of good outcome following ERT. We hypothesized that perfusion imaging–based selection would be associated with better functional outcomes at 3 months compared with NCCT-based selection alone.