Sparse emission pattern in spectral blood Doppler

Spectral Doppler ultrasound imaging allows quantification of blood flow by estimating the velocity distribution of the blood within a range gate on a single image line. In applications, it is desirable to have both brightness mode (B-mode) at high frame rate, to allow the medical doctor to visualize and follow vessel movement, as well as Doppler mode with high spectral resolution of the velocity distribution, so that changes in blood flow can be tracked. In this paper, we propose a slow-time sparse emission pattern of the blood Doppler signal which significantly reduces the number of transmissions sent. For the proposed sampling scheme, we derive the minimal number of Doppler emissions allowing reconstruction of the signal's power spectrum and provide power spectrum recovery techniques that achieve this minimal rate. Using realistic Field II simulations, we show that accurate estimation of blood velocity spectrum can be performed from only 12% of the transmissions required in conventional scanning. Thus, several vessel regions may be investigated while keeping a high frame rate of the B-mode images.