Abstract: An apparatus and method for processing ultrasound data is provided. The apparatus includes an interface operatively connected to a memory, a programmable single instruction multiple data processor (or two symmetric processors), a source of acoustic data (such as a data bus) and a system bus. The memory stores data from the processor, ultrasound data from the source, and data from the system bus. The processor has direct access to the memory. Alternatively, the system bus has direct access to the memory. The interface device translates logically addressed ultrasound data to physically addressed ultrasound data for storage in a memory. The translation is the same for data from both the processor and the source for at least a portion of a range of addresses. The memory stores both ultrasound data and various of: beamformer control data, instruction data for the processor, display text plane information, control plane data, and a table of memory addresses. One peripheral connects to the ultrasound apparatus.

Abstract: A diagnostic medical ultrasonic imaging system includes a gain processor that varies the receive signal path gain as a function of the signal to noise ratio of the echo signal. Background noise is either acquired or modeled in real time using currently prevailing imaging parameters, and acquired echo signals are compared with the acquired or modeled background noise values. The receive gain is controlled as a function of this comparison to improve the signal-to-noise ratio, and to reduce or prevent the amplification of echo signals that are not greater than the background noise level.

Abstract: A method and system for generating three-dimensional representations using opacity modulation are provided. The opacity level associated with each datum in a 3D volume data set is controlled as a function of at least one Doppler parameter, such as variance. Areas of high variance are assigned a higher level of opacity than areas of low variance. For a Doppler velocity image, velocities associated with high variance are displayed more opaquely than velocities associated with low variance, thereby emphasizing the more opaque regions. The more transparent velocities (i.e., those associated with low variance) still contribute to the image and are displayed. Other Doppler parameters may be used for the image, such as energy, tissue motion or variance. Furthermore, other Doppler parameters may be used to control the opacity, such as velocity, energy or tissue motion.

Abstract: A method and apparatus for quantifying and displaying ultrasound signals in an ultrasonic system are provided. A first signal value for each of at least one spatial location in a region of interest is acquired at a first time, and the signal values are summed to obtain a first surface integral value. A second signal value for each of said at least one spatial location in said region of interest is acquired at a second time, and the second signal values are summed to obtain a second surface integral value. The first surface integral value is summed with the second surface integral value to obtain a time based integral. The time based integral is displayed. Other quantities based on any of various ultrasound parameters, such as Doppler energy, Doppler velocity and B-mode intensity, are calculated and displayed as quantities or as waveforms as a function of time. Furthermore, various comparisons of quantities and waveforms are provided. Image plane data or other ultrasound data are used in the calculations.

Abstract: A method and apparatus for quantifying and displaying ultrasound signals in an ultrasonic system are provided. A first signal value for each of at least one spatial location in a region of interest is acquired at a first time, and the signal values are summed to obtain a first surface integral value. A second signal value for each of said at least one spatial location in said region of interest is acquired at a second time, and the second signal values are summed to obtain a second surface integral value. The first surface integral value is summed with the second surface integral value to obtain a time based integral. The time based integral is displayed. Other quantities based on any of various ultrasound parameters, such as Doppler energy, Doppler velocity and B-mode intensity, are calculated and displayed as quantities or as waveforms as a function of time. Furthermore, various comparisons of quantities and waveforms are provided. Image plane data or other ultrasound data are used in the calculations.

Abstract: A method and apparatus for quantifying and displaying ultrasound signals in an ultrasonic system are provided. A first signal value for each of at least one spatial location in a region of interest is acquired at a first time, and the signal values are summed to obtain a first surface integral value. A second signal value for each of said at least one spatial location in said region of interest is acquired at a second time, and the second signal values are summed to obtain a second surface integral value. The first surface integral value is summed with the second surface integral value to obtain a time based integral. The time based integral is displayed. Other quantities based on any of various ultrasound parameters, such as Doppler energy, Doppler velocity and B-mode intensity, are calculated and displayed as quantities or as waveforms as a function of time. Furthermore, various comparisons of quantities and waveforms are provided. Image plane data or other ultrasound data are used in the calculations.

Abstract: A method and apparatus for quantifying and displaying ultrasound signals in an ultrasonic system are provided. A first signal value for each of at least one spatial location in a region of interest is acquired at a first time, and the signal values are summed to obtain a first surface integral value. A second signal value for each of said at least one spatial location in said region of interest is acquired at a second time, and the second signal values are summed to obtain a second surface integral value. The first surface integral value is summed with the second surface integral value to obtain a time based integral. The time based integral is displayed. Other quantities based on any of various ultrasound parameters, such as Doppler energy, Doppler velocity and B-mode intensity, are calculated and displayed as quantities or as waveforms as a function of time. Furthermore, various comparisons of quantities and waveforms are provided. Image plane data or other ultrasound data are used in the calculations.

Abstract: The energy, power or amplitude of Doppler or time shift information signals is compared to a threshold in order to select a large or small weighting factor for temporal persistence. In the event of a "flash" signal or strong arterial flow signal, a small weighting factor is chosen to reduce the extent of temporal persistence via feedback of the averaged value for the prior frames so that the effect of the "flash" or strong flow signal would quickly dissipate in the imaging of subsequent frames and good temporal resolution preserved for the current frames, while low energy flow signals would cause a large weighting factor to be selected to improve the signal-to-noise ratio of low energy signals. Similar effects can be achieved by clipping the signals to not exceed a certain threshold.

Abstract: In an ultrasound imaging system, the mean velocity of a fluid flow, variance of velocity of the fluid flow and energy value of Doppler ultrasound signals from the flow in response to transmitted ultrasound are first estimated from autocorrelation values of the signals to form a set of parameters for a corresponding sampling time or a corresponding sampling location. An averaging process is then performed on two sets of the estimated parameters corresponding to a plurality of different sampling times in temporal filtering or on two sets of the estimated parameters corresponding to a plurality of different locations in spatial filtering. The filtered parameters are then compared to thresholds in a discrimination process to reject noise and clutter.

Abstract: The invention provides a method and system for adaptive persistence processing in an ultrasound imaging system. Acoustic signals are temporally filtered using an adaptive persistence filter, having a recursive stage followed by a nonrecursive stage. A set of filtering coefficients for each stage are supplied by a look-up table in a memory, addressed or indexed in response to a plurality of input or output pixel values. The look-up table may therefore embody any selected function of its input variables. The input variables for the look-up table function are a current input pixel value X.sub.n and a previous intermediate pixel value W.sub.n-1, and the function embodied by the look-up table includes a relative first difference function for selecting a filter coefficient. A recursive filtering coefficient .alpha. is held constant over time, while a nonrecursive filtering coefficient .gamma.is adjusted dynamically in response to the current input pixel value X.sub.n and the previous intermediate pixel value W.sub.

Abstract: A user defines a line of study by two or more icons placed on a two-dimensional motion image. A velocity profile or the estimated spectra at each point along the line of study are displayed as a function of position along the line of study. The velocity and variance parameters displayed are computed in reference to velocity direction angles selected by the user. The information displayed is obtained from scan converted information to facilitate the process. One or more spectral strips may be displayed in addition at one or more range gate positions.

Abstract: An ultrasound imaging system of the type having a receive beamformer that acquires multiple receive beams from each respective transmit beam includes an azimuthal spatial filter which operates to correct for geometric distortions typically associated with such multi-beam imaging systems. This azimuthal spatial filter is responsive to input signals derived from the receive beams to generate a corrected signal output as a function of a selected set of receive beams and a set of filter weights. The filter weights are caused to vary in accordance with the azimuthal coordinates of the selected receive beams in order to improve performance.

Abstract: A user defines a line of study by two or more icons placed on a two-dimensional motion image. A velocity profile or the estimated spectra at each point along the line of study are displayed as a function of position along the line of study. The velocity and variance parameters displayed are computed in reference to velocity direction angles selected by the user. The information displayed is obtained from scan converted information to facilitate the process. One or more spectral strips may be displayed in addition at one or more range gate positions.

Abstract: An ultrasonic transducer is rotated until the displayed vessel has the smallest area. The transducer is then tilted to various angles with respect to a normal to a surface to obtain area and velocity measurements of fluid flow inside a vessel in a body imaged. A least mean square error calculation is then performed to find the area and velocity that will minimize such error. The product of these two quantities is the estimated flow.

Abstract: In an ultrasound imaging system, the mean velocity of a fluid flow, variance of velocity of the fluid flow and energy value of Doppler ultrasound signals from the flow in response to transmitted ultrasound are first estimated from autocorrelation values of the signals to form a set of parameters for a corresponding sampling time or a corresponding sampling location. An averaging process is then performed on two sets of the estimated parameters corresponding to a plurality of different sampling times in temporal filtering or on two sets of the estimated parameters corresponding to a plurality of different locations in spatial filtering. The filtered parameters are then compared to thresholds in a discrimination process to reject noise and clutter.

Abstract: The invention provides a method and system for adaptive persistence processing in an ultrasound imaging system. Acoustic signals are temporally filtered using an adaptive persistence filter, having a recursive stage followed by a nonrecursive stage. A set of filtering coefficients for each stage are supplied by a look-up table in a memory, addressed or indexed in response to a plurality of input or output pixel values. The look-up table may therefore embody any selected function of its input variables. The input variables for the look-up table function are a current input pixel value X.sub.n and a previous intermediate pixel value W.sub.n-1, and the function embodied by the look-up table includes a relative first difference function for selecting a filter coefficient. A recursive filtering coefficient .alpha. is held constant over time, while a nonrecursive filtering coefficient .gamma. is adjusted dynamically in response to the current input pixel value X.sub.n and the previous intermediate pixel value W.

Abstract: Methods and apparatus for enhancing the clarity of and the diagnostic information in real-time B-mode and M-mode ultrasound displays including a beamformer for acquiring ultrasound receive signals for each ultrasound scan line of a two-dimensional image and processing the receive signals for each ultrasound scan line into detected and filtered video signals for storage in scan line acquisition memory with programmable dynamically variable non-linear filters for processing the video signals with continuously and automatically varying filter responses over a range of low and high pass responses followed by scan converting and display of the non-linearly processed video signals. The non-linear filters may process video signals in range along each ultrasound scan line or azimuthally along multiple ultrasound scan lines of a two-dimensional B-mode image.

Abstract: An ultrasound tissue imaging system having an acoustic transducer, B-mode imaging means to produce with said transducer an electronically scanned B-mode image of tissue under examination, Doppler imaging means that accepts and processes large amplitude, low frequency signals to produce with said transducer an electronically scanned acoustic image of moving tissue, and color display means for displaying the B-mode image as a two-dimensional image with echo intensities encoded using a first mapping function and for simultaneously displaying Doppler information from moving tissue as a two-dimensional image using a second and distinct mapping function that is spatially coordinated with and superimposed upon said B-mode image to augment the B-mode image.