Does IVIM measure classical perfusion?

MR measurements based on motion encoding gradients provide interesting information about diffusion in tissues and have also been advanced as a way to measure tissue perfusion. This communication shows why IVIM cannot measure perfusion in the classical sense. Attempts to do so result from an unclear understanding of classical perfusion measurements and from confusion between terminal deposition (or uptake) and blood volume flow. © 1990 Academic Press, Inc.