Abstract: An ultrasound wave is transmitted from a probe (120) to a moving reflector (130) and the reflected ultrasound wave is received back by the same probe (120). With n-divided wave bands of the to-be-used spectrum, the ultrasound wave to be transmitted is made up of up chirp signals and down chirp signals from n number of down chirp signal generators (112, 113) and up chirp signal generators (116, 117), creating complementary multiplexed chirp signals through synthesizers (114, 118). Cross-correlation is taken by a correlator between the reception signal received at the probe (120) and the up chirp and the down chirp signals, respectively, so as to provide compressed up and down signals and then combining the obtained compressed signals through synthesizers (144, 148). Doppler measurement is performed by determining the correlation distance through taking the cross-correlation between these compressed signals by a cross-correlator (160) and performing envelope detection by an envelope detector (170).

Abstract: A base band signal is sampled, based on an asynchronous sampling clocking, to output two sampled data series. A transmission side complex symbol frequency generator generates a complex transmission symbol frequency component combining an envelope value and an amplitude change amount value, which are each calculated from the two sampled data series. The transmission side complex symbol frequency component is provided to a correlation value calculator that outputs a correlation data series correlated to the complex symbol frequency and the symbol frequency generated by a cosine wave generator. The correlation data series is converted a timing error by an inverse tangent calculator. By the above configuration, a timing reproducing unit, which includes the above components, determines the timing error at a sampling speed of twice the symbol rate.

Abstract: A 1 ½ D probe is used in acoustic Doppler blood flow imaging to accurately determine the position of blood vessel in three dimensions. The 1 ½ D probe has closely spaced elements in the x direction and widely spaced elements in the y direction. Doppler power measurements are used to determine the y position of the blood vessel to an accuracy better than achieved by prior art techniques.

Abstract: A system for improving vector Doppler velocity measurements by using information about the constancy of the velocity's angle to reduce the errors caused by the intrinsic variability in power of Doppler signals.

Abstract: X-ray mammography has been the standard for breast cancer screening for three decades, but offers poor statistical reliability; it also requires a radiologist for interpretation, employs ionizing radiation, and is expensive. The combination of multiple independent tests, performed effectively at the same time and co-registered, can produce substantially more reliable detection performance than that of the individual tests. The multi-sensor approach offers greatly improved reliability for detection of early breast tumors, with few false positives, and also can be designed to support machine decision, thus enabling screening by general practitioners and clinicians; it avoids ionizing radiation, and can ultimately be relatively inexpensive.

Abstract: The invention concerns an assembly comprising: (a) means for determining the intensity of a plurality of electromagnetic signals, (b) a correlator for correlating or autocorrelating said signals, (c) means for continuously calculating the variance and/or the standard deviation of said signals. It also concerns a method for analysing the intensity of a plurality of electromagnetic radiations scattered and/or emitted from solid, fluid or gaseous samples.

Abstract: A method and apparatus is provided for generating and displaying filtered strain rate signals corresponding to tissue structure within a subject in response to complex Doppler signals generated by an ultrasound system. Various combinations of several processing techniques are employed including filtering out high strain rate signals due to reverberation and other sources of noise, complex autocorrelation, velocity signal estimation, real strain rate signal estimation, complex strain correlation signal estimation, complex signal averaging, and real signal averaging. Color strain rate imaging is provided using the techniques such that the color images have reduced noise and improved image quality.

Abstract: A wireless sensing system is configured to measure the distension of a flexible tube. The system includes a sensing unit having a sensor element that attaches to the tube and which causes a quiescent frequency produced by the sensing unit to change when the sensor element is physically distorted by distension of the tube. A scanning unit of the system remotely and wirelessly triggers the sensing unit to power up and transmit a modulated signal to the scanning unit for decoding, where the decoded signal indicates a measured quiescent frequency of the sensing unit. The wireless sensing system may be employed, for example, to measure the distension of a blood vessel for the purpose of monitoring blood pressure.

Abstract: A signal processing utility is disclosed involving time-to-frequency domain transforms for applications including medical diagnostic signal processing. Such transforms can be used to define a continuous spectral density function or other spectral density function including nonzero values at irregularly spaced frequency intervals. The invention thereby enables more accurate representation of certain real spectra and reduced spectral broadening. The utility also accounts for digitization errors associated with analog-to-digital conversion. The invention has particular advantages with respect to medical contexts where the received signal has a changing spectral content as a result of interaction of an interrogating signal with moving physiological material such as blood flowing through an artery.

Abstract: In an ultrasonic diagnostic imaging system, the parameters which govern the display of Doppler information are automatically optimized to make better use of the display range or area. Spectral Doppler information may be used to optimize a spectral display or a colorflow display, and colorflow Doppler information may be used to optimize a spectral display or a colorflow display. The optimization may be invoked by a manual user control which automatically optimizes one or a plurality of display parameters. Automatic optimization may be invoked only when called for by the user, or periodically after a time interval, a given number of heart cycles, or when the user has made a change to the display or imaging mode. Preferably the optimization processor runs continuously in the background so that optimized parameters are available immediately when called for. The optimization processor may utilize “hidden” Doppler data which has been acquired but is not used for display purposes.

Abstract: A system and method for simultaneous, bilateral, segmental blood pressure measurement are disclosed. In one illustrative embodiment of the invention, two Doppler modules are configured to operate at nominally the same Doppler carrier frequency so that they probe for substantially the same range of physiological information. However, the Doppler carrier frequencies for the Doppler modules are also sufficiently different to substantially avoid interference between the two modules. A phase-locked loop (PLL) used to demodulate the velocity signals in each Doppler module efficiently blocks interference signals because they have frequencies that are the difference in the Doppler carrier frequencies and that are outside the locking range of the PLL. Broad-band RF amplifiers and Doppler transducers are used to ensure that the frequency responses of the Doppler modules are substantially the same.

Abstract: Methods and systems are provided for automatic optimization of spectral Doppler ultrasound imaging. One or more of the velocity scale (e.g., pulse repetition frequency), gain, baseline, dynamic range or other imaging parameters are optimized based on one or both of: (1) determining the optimum parameter based on data acquired at a standard or predetermined setting of the parameters and (2) identifying an artifact in the Doppler ultrasound data and discarding or minimizing the influence of the artifact on any determination of imaging parameter settings. One embodiment used for cardiac Doppler imaging identifies artifact signals using the maximum or minimum traces. For example, the velocity scale or pulse repetition frequency is set based on the maximum or minimum velocity value over one or more heartbeats identified from a maximum and minimum trace of the signal envelope or Doppler spectrum.

Abstract: A Doppler ultrasound system automatically and repeatedly scans an area of interest to construct at least one velocity profile through segments of arteries over an area of interest. Each scan includes taking measurements of blood flow in the area of interest substantially simultaneously from different angles. The velocity profiles and delta velocity profiles are automatically analyzed to determine a number of parameters indicative of potentially stenotic areas within the artery. The parameters and their changing value along the length of the artery indicative of stenosis are detected and compared with predefined threshold values to determine potentially stenotic areas. Scanning by the Doppler ultrasound system is triggered at a predefined point in an ECG cycle of the patient.

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: An ultrasound information processing system is disclosed in which ultrasound image data is packetized into ultrasound information packets and routed to one or more of a plurality of processors for performing image processing operations on the ultrasound image data, the ultrasound information packets being routed according to entries in a host-programmable routing table. A common distribution bus is coupled between packetizing circuitry and dedicated input buffers corresponding to each processor for distributing the ultrasound information packets, and a common output bus to is used to transfer processed image data from the processors to an output device. The disclosed ultrasound information processing system architecture allows for a high throughput rate for accommodating real-time image processing operations, while also allowing for ready programmability and upgradability.

Abstract: A method is provided for observing three-dimensional pulsatile activity in a volume of a subject's tissue, which includes activating an ultrasonic probes array (25) subset portion (20) having a curvature including focussing the ultrasound energy of probes (25) constituting a selected contiguous portion of the subarray in a selected portion of a selected slice of tissue (21) along a line, converting the reflected ultrasound energy to output signals and providing output data corresponding to the pulsatile activity, varying the focus of ultrasound energy along the line and repeating the converting and processing steps to thereby select additional lines within the selected slice, selecting additional subsets of the ultrasound array of probes so as to select additional slices within the volume, and performing tomographic analysis of the output data corresponding to pulsatile activity in the plurality of selected portions of tissue, so as to obtain a three dimensional image of pulsatile activity in the presele

Abstract: An ultrasonic tomography apparatus has an ultrasonic transmitter for transmitting an ultrasound to an object body; an ultrasonic receiver for receiving ultrasound reflected from an object body and producing an ultrasonic signal; a filter for extracting components of the ultrasonic signal in at least two different frequency bands; and an image generator for generating an ultrasonic tomogram of the object body based on the extracted ultrasonic signal component in a first frequency band and the extracted ultrasonic signal component in one or more second frequency bands. The first frequency band centers on a frequency band at the time of transmission, and the second frequency band is shifted from the frequency band at the time of transmission.

Abstract: A prior application discloses a novel probe geometry that offers a wide field of view in an ultrasonic imaging device. That geometry is referred to as a “thinned array” of transducer elements. The application discloses an improved probe geometry permitting high-resolution imaging of a large volume of the subject's body. In this improved geometry, the array elements are non-uniform in size and spacing. The probe is intended for use, for example, in a method of determining parameters of blood flow, such as vector velocity, blood flow volume, and Doppler spectral distribution, using sonic energy (ultrasound) and a novel thinned array. Also in a method of tracking blood flow and generating a three dimensional image of blood vessel of interest that has much greater resolution than images produced using heretofore known ultrasound devices and methods.

Abstract: A medical diagnostic ultrasonic imaging system acquires receive beams from spatially distinct transmit beams. The receive beams alternate in type between at least first and second types across the region being imaged. The first and second types of receive beams differ in at least one scan parameter other than transmit and receive line geometry, and can for example differ in transmit phase, transmit or receive aperture, system frequency, transmit focus, complex phase angle, transmit code or transmit gain. Receive beams associated with spatially distinct ones of the transmit beams (including at least one beam of the first type and at least one beam of the second type) are then combined. In this way, many two-pulse techniques, including, for example, phase inversion techniques, synthetic aperture techniques, synthetic frequency techniques, and synthetic focus techniques, can be used while substantially reducing the frame rate penalty normally associated with such techniques.

Abstract: An ultrasonic imaging apparatus having a depth range setter 28 for setting a threshold value of detection level for a Doppler signal in an ultrasonic circuit unit 2, a unit for extracting a time at which the Doppler signal exceeds the set detection level and a signal level in excess of the set detection level, and a ROI depth data generator 29 for determining, for an adaptive phase controller 3, a ROI depth range for correction necessary to make echo signals of neighboring channels be in phase by using the extracted time and signal level, whereby the focal point can follow the ROI region in an object to be inspected by correcting echo signals from the region where the intensity of the Doppler signal reaches the detection level or its neighboring region so as to make them be in phase between adjacent transducers.

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: For the purpose of removing an effect of window processing in window-processing time-domain Doppler signals, translating them to a frequency domain, and then translating them back to the time domain, when cutting signals of a predetermined length from a time-domain Doppler signal; performing window processing on the cut signals; transforming the window-processed signals into frequency-domain signals by Fourier transformation; inversely transforming the frequency-domain signals by inverse Fourier transformation into a time-domain signal after performing predefined processing on the signals; and outputting the time-domain signal as an acoustic signal, the window processing is performed using a window having a profile with a flat top; and the cutting from the Doppler signal is performed such that a former cut signal and a latter cut signal overlap in a portion corresponding to the flat portion of the window.

Abstract: The present invention is related to cerebral blood flow velocity monitoring method and system, specifically a transcranial Doppler device for odor matching and odor selection in canine and human subjects. The method and system is non-invasive with high temporal resolution, user-friendly and portable, including steps of obtaining a subject's baseline mean blood flow velocity in cerebral arteries using transcranial Doppler instrument with sample volume focused on cerebral vessels on both sides using two probes placed on the temples and calculating laterality index for both arteries. Simultaneously, testing the subject with odors while monitoring mean blood flow velocity during each odor in real-time. The acquired data is processed using an operatively attached microprocessor and using a cellular telephone to communicate the results to a computer workstation for further data analysis and storage.

Abstract: A method of detecting heart beat coincidence includes receiving first and second signals from first and second heart beat sources. The method further includes detecting first heart beat occurrences on the first signal, each first heart beat occurrence having a respective time associated therewith and detecting second heart beat occurrences on the second signal, each second heart beat occurrence having a respective time associated therewith. The method further includes comparing the times of the first and second heart beat occurrences to detect coincidence.

Abstract: An ultrasound machine is disclosed that displays a color representation of moving structure, such as a cardiac wall tissue, within a region of interest on a monitor. The color representation is generated by displaying color hues corresponding to a movement parameter of the structure, such as velocity or strain rate in such a manner as to provide for quantitative visualization of movement parameter gradients. The movement parameter is mapped to the color hues by apparatus comprising a user interface that allows the user to input color band resolution and a local range of relative parameter values. A front-end generates received signals in response to ultrasound waves. A Doppler processor generates a set of parameter signals representing absolute values of the movement parameter within the structure. A set of color characteristic signals is generated by a display processor in response to the set of parameter signals and to a user-defined local range of relative parameter values.

Abstract: An apparatus and method for detecting the highest velocity of fluid flow with in a volume having multiple sources of fluid flow with different velocities. There are multiple pairs of receiving transducers arranged about a region wherein each transducer in a pair is positioned on the same axis with respect to the region. A transmitting transducer is positioned at the region to provide an output frequency signal, which frequency signal is transmitted to the fluid flow area volume. This causes Doppler shifted frequency signals to be reflected, with the Doppler shift being a function of the fluid flow velocity. Each of the receiving transducers receive the Doppler shifted signals. Signal processing means are responsive to the Doppler shifted signals and the original transmitted output frequency signal to process those signals to provide a velocity signal for each pair of transducers. One then selects the maximum velocity signal obtained from the pair.

Abstract: Two-dimensional distribution data of velocities on a moving object in an object to be examined is obtained. A motion field which defines the motion direction of a tissue is stored. A plurality of tracking points are obtained in a tissue range in the two-dimensional distribution data. The moving positions of the tracking points are estimated and the positions are sequentially tracked. Velocities toward the motion direction defined by the motion field are obtained on the basis of the two-dimensional distribution data. One intermediate output value is obtained by performing a predetermined computation by using velocities toward the motion direction at tracking positions of at least two tracking points in each time phase. The values of intermediate positions are obtained by performing weighted addition of intermediate outputs at different positions. A display image is generated and displayed by using the values of the intermediate positions.

Abstract: Exemplary embodiments are directed to providing a method of preparing an anatomical vessel contained within a tissue bundle for ligation, including positioning a cannula adjacent to the tissue bundle, wherein the positioning is non-penetrating, the cannula including a first extendable member, a second extendable member, a Doppler wand, and a distal end, transmitting ultrasound signals toward the vessel through the tissue bundle with the Doppler wand, receiving ultrasound signals reflected by the vessel through the tissue bundle with the Doppler wand, invaginating the tissue bundle with the first extendable member on a first side of the tissue bundle, invaginating the tissue bundle with the second extendable member on a second side of the bundle opposite the first side, and interpenetrating a length of ligation material between the first and second extendable members on a side of the vessel opposite the cannula distal end.

Abstract: A compression and ligation device includes a pair of jaws including one or more Doppler chips oriented to send and receive Doppler signals across the jaws, to assist a practitioner in determining whether or not a uterine artery is between the jaws. A suture leader with an attached suture can be pushed through a channel on one of the jaws, through tissue behind the uterine artery, into another channel on the other jaw, and proximally out the device so that the practitioner can ligate the artery and effect hemostasis.

Abstract: A guiding catheter includes a Doppler sensor disposed at a distal end of a flexible shaft. The Doppler sensor can sense a blood flow turbulence level within a chamber of the heart or a blood vessel of the heart. Detecting changes in a blood flow turbulence level is used to assist guiding of the distal end of the flexible shaft. The Doppler sensor may include a piezoelectric sensor or an optical sensor. The sensor readings may be processed to show turbulence through a time domain or frequency domain presentation of velocity. The sensor readings can be used to modulate an audible waveform to indicate turbulence. The guiding catheter may further include steering apparatus enabling deflection of the distal tip.

Abstract: Modern portable communications units, and in particular cellular telephones, can contain several frequency bands for receiving and several frequency bands for transmitting signals. Typically these units contain a baseband unit and a frequency synthesizer unit, which may be embodied as VLSI integrated circuits. The baseband unit commonly contains the user interfaces and control signals for controlling other portions of the circuitry. The second unit is sometimes called a frequency synthesizer unit. The second unit is dedicated to producing frequencies that are used by the communications system to create RF signals for broadcast and also to take RF signals and extract the modulated signal from them for decoding. As personal communications units have begun using an increasing number of bands it is often necessary to configure different filters to receive or broadcast the different bands. Typically, the baseband Integrated Circuit or separate circuitry does this filter configuration management.

Abstract: A strobed blood flow meter provides periodic measurements of blood flow velocity or volumetric blood flow over a cardiac cycle at reduced average power consumption, which is advantageous for reducing battery size, and extending device battery life, such as in an implantable application. Continuous wave Doppler, pulsed Doppler, laser Doppler, transit time, electromagnetic flow, and thermal dilution techniques are included. Strobing provides higher level excitation during active periods, which improves signal-to-noise ratio, and provides a low power standby mode during an idle time between active periods. The invention may be used for chronic or acute applications. Doppler or other signals may be telemetered from an implanted portion of the flow meter for further signal processing to extract velocity or volumetric flow. Alternatively, such signal processing is also implanted, such that the velocity signal can be telemetered to an remote monitor.

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 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: The invention relates to a device for measuring the change in the diameter of a vein by the Doppler effect. The device operates such that when a first signal is generated, it controls a transmission and reception probe in continuous mode in order to obtain an audible signal from a speaker as a function of the position of a transmission and reception probe relative to a vein in order to locate the vein, and when a second signal is generated once the vein has been located, the second signal controls the transmission and reception probe in discontinuous mode and, from the changes in frequency between the transmitted and received ultrasonic waves, determines the diameter of the vein to ensure that its changes are displayed.

Abstract: The present invention relates to a method and associated apparatus for improving the accuracy with which the speed of a fluid, such as a liquid, in particular blood flowing in a duct, such as a blood vessel, in particular the aorta, is measured by means of a signal emitted by a Doppler transducer (4). In characteristic manner, according to the method, the Doppler transducer is associated with a programmable memory (50) which contains at least one correction data item for correcting the Doppler signal transmitted by the transducer (4) to a transducer control and computer unit (8). Said computer unit (8) incorporates said signal correction data item in its computation (at 16) of each speed measurement on the basis of each signal emitted by the Doppler transducer, and it computes the speed value while taking account of said correction data item so as to provide a corrected measurement of the speed of said fluid, thereby improving its accuracy.

Abstract: An ultrasound system is disclosed that includes a method and apparatus to automatically adjust certain parameters that affect visualization of a Doppler spectral image. The ultrasound system acquires spectral lines of Doppler data generated by the ultrasound system. A data processor within the ultrasound system determines the presence of aliasing and estimates noise levels from the spectral lines of Doppler data. The data processor then automatically adjusts system parameters such as pulse repetition frequency (PRF), baseline shift, and spectrum orientation in response to aliasing and noise levels. The data processor of the ultrasound system also determines positive and negative signal boundaries for each spectral line of Doppler data and a display architecture processes the signal boundary data to display a spectral trace corresponding to the edges of the spectral lines.

Abstract: An ultrasound machine that generates a color representation of moving structure, such as cardiac wall tissue within a region of interest, and is displayed on a monitor. The color representation is generated by displaying at least one color characteristic related to a set of signal values of the structure, such as velocity or strain rate. The related feature of the set of signal values is mapped to the color characteristic by an apparatus comprising a front-end that generates received signals in response to backscattered ultrasound waves. A Doppler processor generates a set of signal values representing a spatial set of values of the moving structure. A host processor embodies a tracking function and a time integration function to generate tracked movement parameter profiles and displacement parameter values over a time period corresponding to sampled anatomical locations within the region of interest. The displacement parameter values are then mapped to color characteristic signals.

Abstract: The present invention is directed to an ultrasound imaging system and method for Doppler processing of data. The ultrasonic imaging system efficiently addresses the data computational and processing needs of Doppler processing. Software executable sequences in accordance with a preferred embodiment of the present invention determines the phase shift and the auto-correlation phase of filtered image data. In a preferred embodiment, the system of ultrasonic imaging also includes a sequence of instructions for Doppler processing that provides the functions for demodulation, Gauss Match filtering, auto-correlation calculation, phase shift calculation, frame averaging, and scan conversion implemented with Single Instruction Multiple Data (SIMD) or Multiple Instruction Multiple Data (MIMD) instructions.

Abstract: Microcapsules are prepared by a process comprising the steps of (i) spray-drying a solution or dispersion of a wall-forming material in order to obtain intermediate microcapsules and (ii) reducing the water-solubility of at least the outside of the intermediate microcapsules. Suitable wall-forming materials include proteins such as albumin and gelatin. The microcapsules have walls of 40-500 nm thick and are useful in ultrasonic imaging. The control of median size, size distribution and degree of insolubilization and cross-linking of the wall-forming material allows novel microsphere preparations to be produced.

Abstract: An ultrasonic Doppler flow phantom is described which is formed of tissue-mimicking material containing a plurality of fluid flow paths through which fluid is pumped. The fluid flow paths are made of tubing and each extends over a different portion of the depth of the phantom and at a different angle. Each path is individually accessible by a probe located on the simulated skin surface at the top of the phantom, enabling the performance of the probe to be evaluated over a wide range of depths from shallow to very deep and over several flow angles.

Abstract: An ultrasound system that performs image processing in the digital domain, including CW Doppler. The ultrasound system is provided with a transducer having a plurality of elements and an ultrasound receiver with a plurality of channels. Each channel receives an analog echo signal and outputs a digital representation of the analog echo signal using an A/D converter capable of converting a signal with a dynamic range of at least 154 dB.

Abstract: Techniques are provided for obtaining selected instantaneous area measurements for a dynamic orifice through which blood is flowing in at least one direction, for obtaining instantaneous flow rates of blood passing through such a dynamic orifice and for obtaining flow volume for blood passing through a dynamic orifice. All of these techniques involve ensonifying a thin sample volume of blood flow exiting at the orifice, which volume is in a region of flow which is substantially laminar, such region normally being the vena contracta for the orifice, with an ultrasonic pulsed Doppler signal, receiving backscattered signal from blood within the sample volume and forming a power-velocity spectrum from the received backscattered signal. Techniques are disclosed for assuring that only laminar flow is looked at in forming the power-velocity spectrum.

Abstract: A medical diagnostic ultrasonic imaging system analyzes receive signals generated by the system to adaptively set the interline delay and/or the transmit power to optimize frame rate while reducing or eliminating the wraparound artifact associated with transmit events that are too closely spaced in time for currently prevailing imaging conditions.

Abstract: A method is provided to simultaneously acquire two ultrasound images. A first set of ultrasound pulses are transmitted at a first frame rate utilizing a first mode of operation. The echoes from the first set of ultrasound pulses are received. A second set of ultrasound pulses are transmitted at a second frame rate utilizing a second mode of operation. The first and second frame rates are different. The first set of ultrasound pulses defines an entire image, while the second set of ultrasound pulses defines a partial image. The echoes from the second set of ultrasound pulses are received, and the echoes from the first and second sets of ultrasound pulses are displayed as a single image.

Abstract: Techniques are provided for obtaining selected instantaneous area measurements for a dynamic orifice through which blood is flowing in at least one direction, for obtaining instantaneous flow rates of blood passing through such a dynamic orifice and for obtaining flow volume for blood passing through a dynamic orifice. All of these techniques involve ensonifying a thin sample volume of blood flow exiting at the orifice, which volume is in a region of flow which is substantially laminar, such region normally being the vena contracta for the orifice, with an ultrasonic pulsed Doppler signal, receiving backscattered signal from blood within the sample volume and forming a power-velocity spectrum from the received backscattered signal. Techniques are disclosed for assuring that only laminar flow is looked at in forming the power-velocity spectrum.

Abstract: For the purpose of removing an effect of window processing in window-processing time-domain Doppler signals, translating them to a frequency domain, and then translating them back to the time domain, when cutting signals of a predetermined length from a time-domain Doppler signal; performing window processing on the cut signals; transforming the window-processed signals into frequency-domain signals by Fourier transformation; inversely transforming the frequency-domain signals by inverse Fourier transformation into a time-domain signal after performing predefined processing on the signals; and outputting the time-domain signal as an acoustic signal, the window processing is performed using a window having a profile with a flat top; and the cutting from the Doppler signal is performed such that a former cut signal and a latter cut signal overlap in a portion corresponding to the flat portion of the window.

Abstract: In an ultrasonic diagnostic imaging system, the parameters which govern the display of Doppler information are automatically optimized to make better use of the display range or area. Spectral Doppler information may be used to optimize a spectral display or a colorflow display, and colorflow Doppler information may be used to optimize a spectral display or a colorflow display. The optimization may be invoked by a manual user control which automatically optimizes one or a plurality of display parameters. Automatic optimization may be invoked only when called for by the user, or periodically after a time interval, a given number of heart cycles, or when the user has made a change to the display or imaging mode. Preferably the optimization processor runs continuously in the background so that optimized parameters are available immediately when called for. The optimization processor may utilize “hidden” Doppler data which has been acquired but is not used for display purposes.

Abstract: An ultrasound imaging system capable of generating a flow image from B-mode echo frames. For each location in a target region, phase information is derived from the B-mode echo frames, and frame-to-frame changes in the phase information are processed to detect the presence of fluid flow at that location. A demodulator receives the B-mode echo frames and demodulates them into baseband signal components from which the phase information is derived. Preferably, the demodulator is highly accurate and robust, such that frame-to-frame changes in the phase information are reliably measured. From the reliably measured phase information, a phase shift metric is then computed and thresholded by a user-adjustable threshold value. Flow is present if the phase shift metric is greater than the threshold value and is absent otherwise.

Abstract: Prostate abnormalities such as cancer may be detected by ultrasonic determination of the in-flow kinetics of contrast agent-containing blood in the prostate and/or by observation of disease-related asymmetries in the the spoke-like vascular pattern of the prostate.