Method and system for non-invasive quantification of tissue perfusion obtainable by a destruction-reperfusion process that provide a signal representative of local agent concentration during reperfusion, by deriving at least one local tissue perfusion value. The system is configured to adjust or relate function of time with S-shape characteristics to the signal proportional to the local agent concentration during reperfusion, and making a correspondence between at least one value of at least one parameter of the function with S-shape characteristics with at least one local tissue perfusion value (such as mean velocity, mean transit time, mean flow, perfusion volume) or attribute (such as the blood flow pattern, flow distribution variance or skewness).