Theoretical tissue perfusion from impulse response analysis

Indicator dilution techniques used in conjunction with modern imaging techniques have been used to measure perfusion. The perfusion model developed in this report is developed from linear systems analysis of indicator dilution time concentration curves. Perfusion is equal to the ratio of fractional tissue blood volume to system mean transit time multiplied by correction factors accounting for indicator dispersion and small vessel hematocrit effects. These assumed effects can greatly influence the perfusion calculation. Without correcting for these effects erythocyte indicators overestimate blood volume and underestimate transit time resulting in a large overestimate of perfusion; while plasma labels slightly underestimate blood volume and transit time and therefore perfusion