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Determination of blood velocities for color flow mapping systems involves both stationary echo canceling and velocity esiting factor in color Bow mapping and the optimization and timation. Often the stationary echo canceling filter is the limfurther development of this filter is crucial to the improvement of color flow imaging. Optimization based on in-vivo data is difficult since the blood and tissue signals cannot be accurately distinguished and the correct extend of the vessel a model for the simulation of blood velocity data in which under investigation is often unknown. This study introduces tissue motion is included. Tissue motion from breathing, heart beat. and vessel pulsation were determined based on in-vivo W-data obtained from carotid artery at one condition and in the liver at three con-IO healthy volunteers. The measurements were taken at the ditions. Each measurement was repeated 10 times to cover the whole cardiac cycle and a total of 400 independent RF measurements of 950 pulse echo lines were recorded. The ficial breathing had a peak velocity of 6.2f3.4 m d s overthe motion of the tissue surrounding the hepatic vein from supercardiac cycle, when averaged overthe 10 volunteers. The motion due to the heart, when the volunteer was asked to hold his of t h e carotid artery wall due to changing blood pressure had breath, gave a peak velocity of 4.2f 1.7 mm/s. The movement a peak velocity of 8.9f3.7 m d s over the cardiac cycle. The variations are due to differences in heart rhythm, breathing, pendently by the simulation program, which also includes a and anatomy. All three of these motions are handled indeparametric model for the pulsatile velocity in the elastic vessel. The model can be used for optimizing both color flow mapping and spectral display systems.

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