La RM di diffusione (DWI) e perfusione (PWI) sono da considerarsi tecniche di elezione nello studio dell'ischemia acuta nell'uomo. La DWI permette infatti di evidenziare il danno tissutale dovuto all'ischemia già dopo pochi minuti dall'insulto ischemico. La PWI, d'altra parte, offre la possibilità di valutare l'emodinamica cerebrale e di evidenziare, quindi, aree non ancora danneggiate, ma a rischio di evolvere verso l'infarto. L'uso combinato di queste due metodiche di indagine permette il giusto inquadramento del paziente con ictus ischemico acuto, da un punto di vista prognostico e terapeutico. I dati della letteratura sono riportati e interpretati, sulla base dell'esperienza personale.
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