1. A method for representing flow with a medical imaging system, the method comprising using the medical imaging system to perform the steps of: (a) assigning first display values to each of a first plurality of spatial locations of a first image; (b) tracking a flow direction and magnitude for each of the first plurality of spatial locations; (c) identifying a second plurality of spatial locations as a function of the flow directions and magnitudes, the second plurality of spatial locations corresponding to locations in a second image; and (d) assigning second display values of the second image to each of the second plurality of spatial locations as a function of the first display values of the first image such that the second display values have a perceived similarity to the first display values but shifted spatially between the first and second images.