Abstract: A medical diagnostic ultrasound system comprises several subsystems, such as a transmit beamformer, a receive beamformer, a B-mode processor, a Doppler processor and a scan converter. These subsystems are within the ultrasound data processing path for processing ultrasound data. One or more of these subsystems are implemented with one or more re-programmable logic devices. For example, one or two field programmable gate arrays are used is each subsystem to perform most or almost all of the subsystems essential functionality.

Abstract: The same analytic data is combined in response to different relative phases. The resulting combinations are detected. The combination associated with the maximum magnitude is then selected for further processing. As a result, the complex data is processed across a variety of possible temporal discontinuities using candidate or possible phase shifts. The phase shift with the least cancellation and the associated combination is selected to minimize motion artifact cancellation.

Abstract: An ultrasonic diagnostic imaging system is described in which two planes of a volumetric region which are in different elevation planes are scanned in real time. In one embodiment the two planes are scanned with less than the maximum number of scanlines which the transducer can transmit in a single plane. A user control enables the two planes to be moved laterally without moving the transducer probe. In another embodiment each image plane contains a color box depicting flow or motion in the same respective position in the image. The color boxes of the two images can be sized and positioned in tandem so that both are in the same corresponding area of the two images.

Abstract: A method and apparatus for extracting an envelope curve of a spectrogram, for use in measurement of blood flow velocity by using spectral Doppler techniques, the method comprising steps of: processing RF ultrasound echo signals to obtain Doppler signals; performing spectral analysis on the Doppler signals, to obtain a corresponding power spectrum P(f); estimating a forward maximum frequency fmax+ and a backward maximum frequency fmax? for the Doppler signals at a predetermined moment, according to the power spectrum P(f) of the Doppler signals at the predetermined moment; determining a noise frequency range according to the two maximum frequencies, so as to estimate an average noise power E; and correcting the forward maximum frequency and the backward maximum frequency by using the average noise power E. With the method of the invention, influence from the SNR and bandwidth on the envelope curve may be reduced, so as to be useful for accurate computation of blood flow parameters.

Abstract: An enhanced intraluminal flow measurement system and method is conducive for a low-power ultrasonic system that can use continuous-wave (CW) Doppler sensing and wireless RF telemetry. Applications include measurement of blood flow in situ in living organisms. Implementations include an extraluminal component located outside of a body, such as a human or animal body, containing a lumen. The extraluminal component can be wirelessly coupled via an RF magnetic field or other RF field to an implantable intraluminal component. The intraluminal component (i.e. implant) is implanted inside of the lumen of the body such as a heart or elsewhere in a vasculature (such as in a dialysis shunt). The intraluminal component can telemeter, via RF electromagnetic signals, flow data directly out of the body housing the intraluminal component to be received by the extraluminal component.

Abstract: An enhanced intraluminal flow measurement system and method is conducive for a low-power ultrasonic system that can use continuous-wave (CW) Doppler sensing and wireless RF telemetry. Applications include measurement of blood flow in situ in living organisms. Implementations include an extraluminal component located outside of a body, such as a human or animal body, containing a lumen. The extraluminal component can be wirelessly coupled via an RF magnetic field or other RF field to an implantable intraluminal component. The intraluminal component (i.e. implant) is implanted inside of the lumen of the body such as a heart or elsewhere in a vasculature (such as in a dialysis shunt). The intraluminal component can telemeter, via RF electromagnetic signals, flow data directly out of the body housing the intraluminal component to be received by the extraluminal component.

Abstract: A method, system and apparatus for ultrasonically imaging boli that are swallowed, as they are passed through the esophagus. The trajectories of the boli are tracked, and image data corresponding to the esophagus thereby identified. Analysis of boli and esophagus image data enable esophageal parameters correlated thereto to be determined.

Abstract: A method of measuring blood flow including several steps. In an initial step a first ultrasound beam is oriented in a direction substantially perpendicular to the direction of the blood flow to be measured. Next, the Doppler spectrum obtained from the backscattered echoes of said first ultrasound beam is measured. Subsequently, the ultrasound beam is reoriented so that the Doppler spectrum of the backscattered echoes of the ultrasound beam is substantially symmetrical around the zero frequency. The Doppler frequency of the backscattered echoes of a second ultrasound beam oriented at a fixed angle to the first ultrasound beam is then measured. Finally, the rate of blood flow is calculated based on the angle between the ultrasound beams and the measured Doppler frequency of the backscattered echoes of the second ultrasound beam.

Abstract: Methods and systems for automatic optimization in spectral Doppler ultrasound imaging are provided. The value for one or more spectral Doppler parameter is optimized using numerical optimization rather than predefined sampling. Various spectral Doppler parameters are set, such as a position of the gate, gate size, transmit frequency, filter settings, Doppler gain, beamline orientation or angle of intersection between the gate position and the scan line, aperture size, or other spectral Doppler transmit or receive parameters effecting the spectral Doppler imaging. A processor automatically calculates a setting or value for one or more of the spectral Doppler parameters, resulting in more objective optimization than provided by a user setting.

Abstract: An ultrasonic Doppler blood flow meter has a clutter component estimation unit 110 for estimating amplitude, initial phase, and phase velocity of the clutter component using an output from the phase detector 104 to reduce a transient phenomenon. Using the estimated data, initial values of the wall filter 105 are generated by the initial filter value generating unit 11 and then provided to the wall filter for the filtering process.

Abstract: System and method for automatically measuring the delay of tissue motion and deformation. For example, asynchrony may be measured between the left and right ventricles and within the left ventricle. A measurement feature may be defined by default or obtained using a user input. A reference time and a search interval are identified. The search interval may be based on the reference time, or input or modified by a user. A time delay of the measurement feature within the search interval is calculated for each sample. At least one color is assigned to the samples corresponding to the calculated time delay.

Abstract: The present invention relates to an ultrasound system and a method of forming a Doppler mode image. The ultrasound system comprises a transmission/reception unit operable to transmit/receive ultrasound signals at a pulse repetition frequency (PRF) to form an n number of Doppler signals. The ultrasound system further comprises a signal processing unit. The signal processing unit computes a first mean frequency based on an nth Doppler signal and an (n?1)th Doppler signal and a second mean frequency based on an nth Doppler signal and an (n?k)th Doppler signal, wherein k is a positive integer equal to or greater than 2. The signal processing unit estimates a Doppler frequency and compensate for aliasing of the Doppler signal based on the first and second mean frequencies to produce Doppler signal with the aliasing compensated. An image processing unit operable to form a Doppler mode image based on the Doppler signals produced by the signal processing unit.

Abstract: The present invention is to provide a velocity measuring method and a velocity measuring device for carrying out the method.

Abstract: A Doppler sensitivity measuring unit measures the Doppler sensitivity of Doppler spectrum data obtained by ultrasonic wave transmission/reception with respect to a predetermined region of an object to be examined. A spectrum shape model generating unit generates a spectrum shape model on the basis of a window function used when the above Doppler spectrum data is generated. A threshold setting unit sets a threshold range in which trace waveform data displaces by a predetermined amount in the frequency axis direction on the basis of the spectrum shape model and the Doppler sensitivity, and sets a predetermined number of thresholds at almost equal intervals in the threshold range. A trace data generating unit selects a threshold for the acquisition of desired trace waveform data by generating trace waveform data while sequentially updating the plurality of set thresholds.

Abstract: A scanner transmits and receives ultrasonic waves at a specified pulse repetition frequency (PRF). A storage stores received signals acquired through the transmission and reception. A calculator generates a Doppler spectrum image by executing frequency analysis on the received signals. A display displays the Doppler spectrum image. When a desired Doppler velocity range for the displayed Doppler spectrum image is inputted, a processor reads out the received signals from the storage, and executes a resampling process on the read-out received signals at a sampling frequency corresponding to the desired Doppler velocity range. The calculator generates a new Doppler spectrum image by executing frequency analysis corresponding to the desired Doppler velocity range on the received signals having been subjected to the resampling process by the processor. The display displays the new Doppler spectrum image.

Abstract: A method and apparatus are disclosed for automatic optimization of Doppler imaging parameters. The method includes obtaining and storing at least two characteristic spectral lines at a predetermined pulse repetition frequency. The method further includes optimizing at least one of the Doppler imaging parameters based on the stored at least two characteristic spectral lines and a predetermined mean noise power. In one embodiment, the characteristic spectral lines are obtained by collecting in real time the Doppler spectral lines generated at the predetermined pulse repetition frequency within a predetermined time period, and processing the collected Doppler spectral lines in real time without storing them.

Abstract: Methods and devices are described for estimating blood flow characteristics through an orifice of a subject, such as regurgitant blood flow through a faulty heart valve. Acoustical techniques can be applied to send bursts of energy, such as high repetition pulsed ultrasonic signals, to a sample volume in a region of interest. For example, multiple beams can be formed from the bursts of energy each having a cross sectional area that is smaller than the cross sectional area of the orifice being investigated. By combining the multiple beams, a composite measure of the blood flow characteristics through the orifice can be obtained. In one example, the composite measure can provide an estimate of the cross sectional area of the interrogated orifice. The composite measure can also provide an estimate of the geometry of the orifice. Systems and components for providing such composite measures are also disclosed.

Abstract: A method and apparatus for automated detection of a general, non-sinusoidal type of periodicity in ultrasound Doppler signals from pulsatile blood flow is described. The method computes a pulsation index, which is a sum of the normalized powers of the fundamental and several harmonic components in the frequency spectrum of the banded Doppler signal. A weighting function may be applied to the power from each harmonic component in order to suppress contributions due to spurious peaks, as in the case when pulsatile flow is absent.

Abstract: In an ultrasonic imaging device having an image synthesizing unit, correlation between images to be synthesized is computed for balancing between an improvement in contrast resolution and an improvement in spatial resolution, and an amount of displacement between the images is computed. When the amount of displacement is large, the signals after envelop detection are synthesized. When the amount of displacement is small, RF signals are synthesized. Alternatively, the mixing frequency may be variable according to the amount of displacement, and the balance between an improvement in spatial resolution and that in contract resolution is achieved according to a degree of the positional displacement.

Abstract: An implantable, multichannel pulsed-Doppler biotelemetry system is described that uses novel power management techniques to minimize power consumption to very low levels, thus, making such system suitable for long term implantation. A first power management technique described in this invention is implemented as a Closed-loop Doppler flowmeter hardware with adjustable pulse repetition rate (PRF) circuits based on a feedback circuit. Another power management technique used in the system described in this invention is implemented as a PRF-synchronized ultrasonic transducer excitation power supply. Finally, another power management technique is implemented as an adaptive sub-sampling multiplexing that enables multiple channels of flow measurement using only a single flowmeter and acquires the blood flow signal at significantly lower rates than typical Doppler flowmeters.

Abstract: A multiple ultrasonic beam is transmitted from an ultrasonic probe, and a velocity of blood flow, azimuth and elevation angle of a sample such as a blood flow are acquired by a three-dimensional information acquisition section, as three-dimensional fluid information in a range gate, based on a Doppler signal output from the ultrasonic probe.

Abstract: A transmission wave corresponding to an FM continuous wave having been subjected to an FM modulation processing is transmitted from a transmitting transducer 10. A pre-amplifier 16 generates a reception RF signal and outputs the reception RF signal to a receiving mixer 30. The receiving mixer 30 applies orthogonal detection to the reception RF signal to generate a complex signal. A reference signal supplied to each mixer in the receiving mixer 30 is generated based on an FM continuous wave output from an FM modulator 20. The FM continuous wave output from the FM modulator 20 is delayed by a delay circuit 25, and one signal is directly supplied to a mixer 32 whereas the other signal is supplied to a mixer 34 via a ?/2 shift circuit 26. The delay circuit 25 applies a delay processing in accordance with a depth of a target position within a living organism to the FM continuous wave.

Abstract: Ultrasonic pulse echo object classification is described. A broadband ultrasound transducer transmits a broadband ultrasound pulse towards the object and detecting an associated ultra sound echo of that pulse from the object. An ultrasound receiver receives the detected echo signal. A signal processor, coupled to the ultrasound receivers determines and analyzes a time duration parameter and a frequency parameter (and possibly one or more other parameters like amplitude and/or phase) of the detected echo signal and classifies the object as a solid or liquid or as gaseous based on the parameters of the detected echo signal.

Abstract: The embodiments contemplate systems and methods for detecting moving tissue within an object. In one such method, a transducer is directed to transmit a first and second ultrasound pulse at a sample volume within a patient. The transducer receives a first and second echo signal of the first and second ultrasound pulses containing information related to the sample volume. A determination is made from the information as to the location and type of blood vessel located within the sample volume, and the located blood vessel information is processed to create an audio representation of the blood flow within the located blood vessel.

Abstract: The present invention is a method for assessment of color processing mechanism in the human brain using cerebral blood flow velocity monitoring, specifically transcranial Doppler ultrasound. The method including steps of transluminating color discs from a light source of a specific color temperature, which act on the visual pathways and color centers to alter mean blood flow velocity in the cerebral arteries. The mean flow velocity is analyzed and using Fourier computation to calculate spectral density estimates. Opponent mechanism in the cortical and subcortical regions determined as opposing tendency for short wavelength versus medium wavelength or for medium wavelength versus long wavelength colors. The method is applied for diagnosis, and treatment of variety of conditions.

Abstract: A system and method for enhancing and displaying a target object, that generally comprises: a processor that demodulates the rate of movement of the target object to produce a demodulated signal; computes the power of the demodulated signal; creates an image sequence, based on the power of the demodulated signal, that comprises the enhanced periodic motion pixels; and forms an image sequence of the enhanced periodic motion pixels to form an image display of at least the target object; and an image display device to display the target object.

Abstract: An ultrasound diagnosis apparatus includes a probe, a controller, a processor, and an output unit. The probe is configured to perform an interleaving scan in Doppler groups of ultrasound beam directions so as to acquire first and second Doppler-mode image frames. The controller is coupled to the probe and configured to control the first probe to treat a last group of the ultrasound beam directions for the first Doppler-mode image frame and an initial group of the ultrasound beam directions for the second Doppler-mode image frame as one Doppler group of the ultrasound beam directions. The processor is coupled to the probe and configured to detect a Doppler-mode signal based on the interleaving scan so as to prepare the first and second Doppler-mode image frames. The output unit is coupled to the processor and configured to output the prepared first and second Doppler-mode image frames.

Abstract: An ultrasound system is provided comprising an ultrasound probe having a 2D matrix of transducer elements transmitting a continuous wave (CW) Doppler transmit signal into an object of interest. The CW transmit signal includes a dither signal component and the probe receives ultrasound echo signals from the object in response to the CW transmit signal. The probe generates an analog CW receive signal based on the ultrasound echo signals. An analog to digital (A/D) converter converts the analog CW receive signal to a digital CW receive signal at a predetermined sampling frequency and a processor processes the digital CW receive signal in connection with CW Doppler imaging.

Abstract: An ultrasonic diagnostic apparatus includes a Doppler velocity information acquiring unit, a region-of-interest-setting unit and an instantaneous flow calculating unit. The Doppler velocity information acquiring unit is configured to acquire three-dimensional Doppler velocity information from an object by a three-dimensional scan with transmission and reception of an ultrasonic wave. The region-of-interest-setting unit is configured to set a region of interest spatially. The instantaneous flow calculating unit is configured to calculate an instantaneous blood flow in the region of interest with using the three-dimensional Doppler velocity information.

Abstract: Methods and systems are provided for automatic optimization for ultrasound medical imaging. In one approach, velocity values are unwrapped to avoid aliasing artifacts. Multi-dimensional phase unwrapping is applied to the velocity data. The unwrapped velocity information is used to optimize one or both of the velocity scale (e.g., pulse repetition frequency) and the imaging frequency. For optimizing the scale setting, the distribution of unwrapped velocities from a systolic time period of the heart cycle are used to identify the pulse repetition frequency. For optimizing the imaging frequency, a correlation as a function of depth shows the penetration depth for a given imaging frequency. In a dependent or independent approach, one or more thresholds for velocity or energy in flow imaging are adaptively selected as a function of an amount of clutter. Velocity or other energy information in addition to the clutter information may be used for selecting the thresholds.

Abstract: An ultrasonic diagnostic apparatus has a scanning executing unit, a Doppler signal obtaining unit, a storage unit, a removing unit, a blood flow information obtaining unit, and a B-mode image generating unit. The scanning executing unit executes a first scanning that is iteratively performed by a predetermined period so as to obtain a B-mode image of an object and executes a second scanning that is iteratively performed a predetermined number of times by a first period between the first scanning so as to obtain a two-dimensional distribution of a blood flow information and that is iteratively performed by a second period while inserting the first scanning. The Doppler signal obtaining unit sequentially obtains a Doppler signal from a reflection signal obtained by the second scanning. The storage unit stores, for each raster direction, a Doppler signal string at unequal time intervals collected for the first period and the second period by the Doppler signal obtaining unit.

Abstract: Blood-flow image display equipment for displaying a CFM image that is not affected by a motion of a tissue in an object area during capturing of images or is affected in a reduced manner.

Abstract: The present invention is directed to methods for detecting and evaluating retinal affecting neurodegenerative diseases. A plurality of selected retinal parameters are measured generating an eyeprint signature for a subject. The eyeprint signature can be used to evaluate whether the subject is suffering from a retinal affecting neurodegenerative disease, to monitoring the progression of the neurodegenerative disease, as well as to monitor the effectiveness of a treatment for the neurodegenerative disease.

Abstract: The present invention relates to a method and apparatus for performing motion adaptive frame averaging for ultrasound color flow images used to overcome lag and smearing alias of color due to motion. One embodiment of the present invention comprises an ultrasound machine for generating an color flow imaging responsive to moving tissue. The ultrasound system comprises a front end and at least one processor. The front-end is arranged to transmit ultrasound waves into the moving tissue, generating received signals in response to the ultrasound waves backscattered from the moving tissue. The processor is responsive to the received signals, calculating a motion factor by comparing at least one current b-mode frame with at least one previous b-mode frame, determining motion using at least the motion factor, increasing a level of frame averaging if the motion factor is below a first predetermined threshold, and decreasing the level of frame averaging if the motion factor is above a second predetermined threshold.

Abstract: The present invention generally relates to ultrasound. In particular, the present invention relates to data dependent color wall filters (used in ultrasound imaging devices for example). Certain embodiments of the present invention relate to a color wall filter that provides flash reduction and clutter suppression. One embodiment of the color wall filter comprises an impulse response filter stage (either a finite or infinite impulse response filter) and a bi-quad filter stage that is data dependent. It is contemplated that the bi-quad filter stage may comprise a series of bi-quad filters, wherein the impulse response filter stage is cascaded into at least one bi-quad filter of the series of bi-quad filters.

Abstract: A system and method for ultrasound clutter filtering is provided. A processor is configured to iteratively select an optimal high pass filter for the progressive, ordered filtering of clutter from ultrasound color flow imaging data. The high pass filter input for each iterative selection and ordered set of high pass filters is the same original ultrasound color flow imaging data. The high pass filters have different cutoff frequencies whereby each high pass filter can be implemented using different structures. The system and method allow for filtering of clutter from ultrasound color flow imaging data until the clutter is substantially removed.

Abstract: A system for automatically adjusting color gain of an ultrasound image. Image data passes through a wall filter and is processed into a time-gain compensation curve. Values of the time-gain compensation curve are multiplied with corresponding image data values to compensate for attenuation of image data values with increasing depth in a patient. The values used to generate the time-gain compensation curve may be averaged to reduce localized gain variations and produce an image with smoother intensity transitions. To reduce the effect of a time-gain compensation curve on overall system gain, values of the time-gain compensation curve may be scaled to produce equalized values for the time-gain compensation curve. Values of the time-gain compensation curve may be used to adjust front end gain of an ultrasound system to bring the front end gain within a few decibels of noise floor.

Abstract: Methods for obtaining biometric identification data for an individual using a sensor and a processor coupled to the sensor are presented. In an embodiment, the present invention involves placing a portion of a biological object such as a finger, thumb, palm or foot of the individual proximate to piezo ceramic elements of the sensor and generating an output signal with the sensor that is representative of at least one feature of the biological object. The output signal is processed using the processor to produce biological data useful for identifying the individual. In an embodiment of the present invention, the sensor includes at least fifty thousand piezo ceramic elements arranged in an array. These piezo ceramic elements are spaced on a pitch equal to or less than approximately two hundred microns. A multiplexer couples the output of the sensor to the processor.

Abstract: A cardiac lead is disclosed that includes a first lead body having opposed proximal and distal end portions and an interior lumen extending therethrough. The first lead body includes a sensor for measuring blood flow parameters to facilitate placement of the distal end portion thereof adjacent the coronary sinus. The first lead body has a distal electrode operatively associated with the distal end portion thereof and a proximal electrode operatively associated with the proximal end thereof. The second lead body has opposed proximal and distal end portions. A distal electrode is operatively associated with the distal end portion thereof and a proximal electrode operatively associated with the proximal end thereof. The second elongated lead body is dimensioned and configured for accommodation within the interior lumen of the first lead body.

Abstract: Valvular regurgitation is assessed by identifying a characteristic regurgitation jet in a colorflow image. An M-line is placed over the region of regurgitation and Doppler M-mode information is acquired from the flow convergence region adjacent the regurgitant orifice. The Doppler M-mode information, acquired at a higher acquisition rate than the colorflow frame rate, is used to produce a measure of the regurgitant flow rate and volume through the orifice. The flow rate can be used with velocity data acquired during the regurgitation event to produce a dynamic estimate of the size of the regurgitant valve orifice.

Abstract: A method and device for determining a plurality of cardiovascular parameters are described, wherein the parameters are determined from noninvasively obtained data, thereby obviating the need for invasive procedures such as cardiac catheterization. These determinations are enabled by incorporating fluid dynamics and thermodynamics equations with noninvasively obtained mechanical cardiac event data to estimate a desired cardiovascular parameter. Exemplary parameters obtainable with the method and device include aoritc and mitral valve areas, cardiac left ventricular stroke volume, and aortic and mitral valve pressure gradients.

Abstract: A method for treating myomas or tumors having a pedicle includes the steps of locating the pedicle of a myoma or a tumor using Doppler echography and delivering focused ultrasound to the pedicle.

Abstract: A system for ultrasonic imaging that includes a comparator for comparing at least one Doppler parameter input to a threshold value and generating a first mask. The comparator has a threshold value associated with each Doppler parameter input. A spatial filter is coupled to the comparator and produces a second mask, and a classification operator is coupled to the spatial filter and generates a third mask. The classification operator can effectively compare a value of a given pixel to the value of any nearby neighboring pixels and reclassify any given non-majority pixel to a majority value of the nearby neighboring pixels. An embodiment of the invention further includes a multi-parameter generator that outputs at least one Doppler parameter. The multi-parameter generator has a functional relationship based on at least one Doppler parameter input and at least one of any of the masks. A second spatial filter is coupled to receive the Doppler parameter input.

Abstract: A method for ultrasonic imaging, particularly of moving bodies, such as surgical utensils, tissues, flows, or the like, which includes the following steps:—Periodically emitting ultrasonic pulses along a predetermined view line and with a predetermined repetition rate through one or more transducers;—Receiving the echoes produced by the body and/or the tissues or flows and transforming them into echo signals;—Processing the echo signals for extracting information therefrom and for generating an image based on such information. According the invention, the following steps are additionally provided:—determining a real time vector difference between the echo signals of two pulses successively emitted at predetermined time intervals;—using said difference signal as an information signal for ultrasonic imaging.

Abstract: The invention concerns an ultrasonic image processing method for displaying a composite sequence of images of an artery segment with indication of blood flow velocity and wall movements in function of the cardiac cycle, comprising steps of: forming, at a first rate, a first sequence (131) of blood flow velocity color-coded images and forming, at a second rate, a second sequence (231) of images with wall movement graphics; and constructing said composite image sequence (361) by determining a first set of temporal markers (n1,n2), related to the cardiac cycle, in the first image sequence as the minimum points of a curve (P(n)) of the number of the colored points per image in function of the image instants, determining a second set of temporal markers (k1,k2), related to the same cardiac cycle, in the second image sequence as the minimum points of a curve (D(k)) of the arterial mean dilation in function of the image instants, and by superposing the first and second image sequences by synchronizing the respecti

Abstract: An ultrasound method and medical devices using same provide for various techniques of sampling blood flow velocity, e.g., at several sampling rates. To minimize the energy required for ultrasound monitoring, pulsed Doppler signal packages provided by a pulsed ultrasound circuit are switched in such a way that the repetition rate is the lowest possible and yet sufficiently high to be able to record the blood flow velocity within the heart. For example, an ultrasound circuit may be activated only within a part of the cardiac cycle designated as the Doppler Measurement Interval (DMI); the ultrasound circuit may be switched between an on state and an off state during the DMI; and/or the ultrasound circuit may also be switched on and off in different sampling modes: detection mode and measurement mode (e.g., using different sampling rates).

Abstract: An ultrasound system includes a transmit/receive switch (502), at least one frequency band selection circuit (512), and a selection unit (511). The selection unit (511) is used to determine if the data being received are from tissue or contrast agent regions. Depending on which type of region the data are from, different signal processing techniques are applied to the data. For example for tissue regions, a harmonic filter can be applied to the signal. If the signals are from contrast agent flow regions, both the harmonic filter and a fundamental filter can be used.

Abstract: An ultrasonic diagnostic imaging system and method are presented to determine low rates of blood flow using contrast agents. Pairs of differently modulated pulses are transmitted in several beam directions to acquire echoes which can be combined to separate harmonic frequencies by pulse inversion. The pulses of each pair are transmitted in rapid succession to minimize motional artifacts. The transmission in the different beam directions is time-interleaved, resulting in the sampling of each beam direction over a long ensemble time for the detection of low rates of flow.

Abstract: A Doppler sample point setting apparatus in a ultrasonic tomograph comprises a probe for transmitting and receiving ultrasonic waves to and from an object; a signal processing unit for causing the probe to transmit the ultrasonic waves, receiving and signal-processing ultrasonic reflected echo signals received by the probe, and outputting a ultrasonic tomogram, a bloodstream image and bloodstream information; a display unit for displaying the ultrasonic tomogram, the bloodstream image and the Doppler sample point; and a control unit for automatically setting the position of the Doppler sample point on the basis of the bloodstream information.

Abstract: A diagnostic ultrasound system is provided for displaying a color image of a motion of a tissue scans an ultrasonic pulse signal along a tomographic plane to acquire an electrical echo signal, extracts a Doppler signal from the echo signal, calculates velocity data concerning the motion of the tissue for respective sample points on the tomographic plane on the basis of the Doppler signal, and forms data of a B-mode tomographic image on the basis of the echo signal.