Ultrasound Enhanced Plane Wave Imaging Based on the Harmonic High-Resolution Coherence Factor

In high frame rate imaging (HFRI), plane wave transmission is used most frequently due to its high efficiency. Inevitably, the imaging resolution is affected without focusing. This poses a problem for the accurate detection of small point targets, i. e., microcalcification (MC). To solve this problem, we innovatively combine the harmonic imaging (HI) technique with the coherence factor (CF). Specifically, we apply the harmonic high-resolution coherence factor (HHRCF) to the delay-and-summed (DAS) fundamental radio-frequency (RF) signal. The imaging result thus has the advantages of both modalities. Since there is no time-intense process in the CF calculation, our proposed HHRCF method is suitable for the real-time plane wave imaging. Results from the simulation show an enhancement of more than 15% in resolution with our method while in the phantom experiment the ratio is higher, up to 19%. This method may have taken a step forward for the ultrafast ultrasound MC detection.