Adaptive clutter filtering in high frame rate 3D coronary imaging

Ultrasound imaging of blood flow in the coronary arteries is hampered by small vessel diameters and rapid myocardial motion. This combination makes clutter suppression challenging, resulting in flashing artefacts and signal dropouts. This work investigates whether high frame-rate 3D ultrasound imaging in conjunction with eigen-based clutter filtering can be used to mitigate these problems, making Doppler imaging and measurements of coronary blood flow more feasible. Eigen-based filtering was performed using a packet based approach, where the clutter dimension varied throughout the cardiac cycle. 3D power Doppler images were used to compare the adaptive eigen-based filters to conventional Butterworth filters. The results show the eigen based filter reduced the amount of flashing artefacts, increasing the visibility of the coronary artery also in parts of the cardiac cycle where the myocardium contracts.