Abstract: Flash artifacts in ultrasound flow images are suppressed to achieve enhanced flow discrimination. Flash artifacts typically occur as regions of elevated signal strength (brightness or equivalent color) within an image. A flash suppression algorithm includes the steps of estimating the flash within an image and then suppressing the estimated flash. The mechanism for flash suppression is spatial filtering. An extension of this basic method uses information from adjacent frames to estimate the flash and/or to smooth the resulting image sequence. Temporal information from adjacent frames is used as an adjunct to improve performance.

Abstract: A method and an apparatus for automatically maintaining the Doppler sample gate position at a preselected vessel position in B-mode or color flow images during tissue or probe motion. The sample gate is locked onto the selected vessel automatically when the vessel position has changed. Optionally, the vessel slope cursor is automatically updated when the vessel position has changed. The method employs pattern matching of images from successive frames to determine how much a vessel in the image frame has been translated and rotated from one frame to the next. Preferably, either a cross-correlation method is applied to the imaging data in the spatial domain to determine the relative object translation and/or rotation between image frames, or a matched filtering method is applied to the imaging data in the frequency (i.e., Fourier) domain to determine the relative object translation and/or rotation between image frames.

Abstract: In performing flow imaging using coded excitation and wall filtering, a coded sequence of broadband pulses (centered at a fundamental frequency) is transmitted multiple times to a particular transmit focal position, each coded sequence constituting one firing. On receive, the receive signals acquired for each firing are supplied to a finite impulse response filter which both compresses and bandpass filters the receive pulses, e.g., to isolate a compressed pulse centered at the fundamental frequency. The compressed and isolated signals are then high pass filtered across firings using a wall filter. The wall-filtered signals are used to image blood flow and contrast agents.