Inter-frame clutter filtering for high frequency flow imaging

This study investigates ´inter-frame´ clutter filtering in a high frequency (HF) flow imaging system with the objective of improving the performance of HF microvascular imaging at high frame rates. The approach is to apply the clutter filter on pulse ensembles (corresponding to a specific beam location) acquired in successive frames rather than on ensembles within a single frame. An inter-frame filter exploits the correlation of tissue signals on a time scale of the frame rate, is therefore insensitive to tissue spectral broadening, and thereby can achieve improved sensitivity to low blood velocities.