CT AND MRI PERFUSION IN ACUTE ISCHEMIC STROKE: DIFFERENTIAL DIAGNOSIS OF THE INFARCT CORE AND PENUMBRA FOR PATIENT SELECTION FOR THROMBECTOMY

Abstract

Acute ischemic stroke (AIS) is one of the leading causes of mortality and long-term disability worldwide, affecting more than 13 million people annually [1] [2]. The effectiveness of reperfusion therapy — intravenous thrombolysis (IVT) and mechanical thrombectomy (MT) — fundamentally depends on the accurate differentiation between the irreversibly damaged infarct core and the potentially viable ischemic penumbra [4] [5]. Perfusion computed tomography (CT perfusion) and perfusion magnetic resonance imaging (MRI perfusion), combined with diffusion-weighted imaging (DWI), make it possible to quantitatively assess cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time to maximum (Tmax), thereby enabling visualization of the spatial mismatch between the infarct core and penumbra zones [3] [6]. The use of automated perfusion analysis software (RAPID, MIStar) based on mismatch index criteria has significantly expanded the “therapeutic window” up to 24 hours from symptom onset, as confirmed in the randomized DAWN and DEFUSE-3 trials [7] [8]. The present study is devoted to a comparative analysis of the diagnostic effectiveness of CT and MRI perfusion, quantitative perfusion parameters, and their prognostic significance in selecting patients for mechanical thrombectomy [9] [14].