Abstract: Since a number of ultrasonic beams which are transmitted within unit time is increased, an ultrasonic imaging method is capable of obtaining image information in a high frame rate or improving resolution of the image information. In an ultrasonic imaging method of transmitting an ultrasonic beam toward a measurement target located within an object, receiving an ultrasonic echo and processing detection signals to obtain image information, there are provided with the steps of: (a) executing a pre-imaging operation and setting a region with respect to the measurement target on the basis of an image obtained by the pre-imaging operation; and (b) transmitting an ultrasonic beam in such a manner that the region set in step (a) is scanned and receiving an ultrasonic echo so as to execute an ultrasonic imaging operation.

Abstract: The present invention is directed to a scanhead having an integral beamformer and a transducer assembly that is demountable from the scanhead. The scanhead has a frontal portion including a transducer assembly, and a rear portion including a beamformer. The frontal portion further includes a connective interface to electrically communicate with a corresponding connective interface on the rear portion. In a first embodiment, the frontal portion includes an interior portion with an opening to slidably receive a corresponding portion of the rear portion. In another embodiment, an interposer is positioned between the frontal portion and the rear portion to electrically couple the spaced apart connective interfaces. In still another embodiment, the frontal and rear portions are axisymmetrically-shaped and have corresponding threaded portions to couple the frontal and rear portions.

Abstract: An ultrasound system, comprising: a plurality of interchangeable transducer connector modules (TCMs), wherein each TCM includes an ultrasound connector, a switching circuit, and a pluggable interface; and an ultrasound control unit, wherein the ultrasound control unit includes: a plurality of bays, each for receiving and pluggably coupling one of the TCMs into a distribution bus of the ultrasound control unit, and a system controller for selecting one of the plurality of TCMs and for activating the switching circuit of the selected TCM.

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 coherent imaging system includes a transmitter and a receive beamformer which are programmed with transmit and receive time delays, respectively, that take into account time-of-flight errors caused by an intervening mammography compression plate between the biological tissue being imaged and a phased array of ultrasonic transducer elements. A simple ray-tracing method is utilized to adjust the transmit and receive time delays according to compression plate thickness and speed of ultrasound propagation to mitigate spherical aberration due to the compression plate.

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 AC biasing arrangement for a micro-machined ultrasonic transducer (MUT) is disclosed. The AC biasing arrangement allows the sensitivity of each MUT element in an array to be adjusted without collapsing the MUT membrane. The sensitivity of the MUT element can be adjusted by varying the frequency of the AC bias signal supplied to the MUT element. An alternative embodiment of the invention adds a second AC bias signal having a phase opposite the phase of the first AC bias signal. This arrangement provides a neutral bias signal, thereby removing the large amplitude bias signal from the MUT element.

Abstract: In ultrasound imaging, acquired images are corrupted by slowly varying multiplicative non-uniformity. When the image is corrected for non-uniformity alone, noise in the dark regions of the original image becomes multiplicatively enhanced, thereby providing an unnatural look to the image. A pre-filtering technique is used to reduce noise in ultrasound pixel images by shrinking initial image data and processing the shrunken image with known segmentation-based filtering techniques that identify and differentially process structures within the image. The segmentation is based on both gradient threshold and the distance from the near field of the ultrasound image. This modification selectively suppresses near-field artifacts. After processing, the shrunken image is enlarged to the dimensions of the initial data and then blended with the initial image to form the final image.

Abstract: An ultrasonic imaging system uses a specially configured scanhead to provide ultrasound return signals that are processed by an imaging unit to generate a three-dimensional Doppler ultrasound image. One embodiment of the scanhead includes a first pair of apertures aligned along a first axis, and a second pair of apertures aligned along a second axis that is perpendicular to the first axis. All of the apertures lie in a common plane. Respective signals from the apertures along each axis are processed to generate two-dimensional Doppler motion vectors. The resulting pairs of two-dimensional Doppler motion vectors are then processed to generate three-dimensional Doppler motion vectors that are used to generate a three-dimensional Doppler image. In another embodiment, three co-planar apertures are arranged equidistantly from each other about a common center, and the three-dimensional Doppler image is generated from respective signals from the apertures.

Abstract: A two level power supply and method are provided for ultrasound transmission. A coupling capacitor is provided between a high voltage source and a low voltage source. The coupling capacitor provides direct current restoration for a two level power supply selector connected with an ultrasound transmit array. For example, a clamping circuit, including a capacitor and a diode, is provided between the high voltage and the low voltage sources. The high voltage source connects as a power supply to a pulser. Control signals are provided to the pulser to switch the output between the high voltage and ground depending on the type of ultrasound signal being transmitted. A voltage rail of the transmit array connects with the clamp circuit and receives a low voltage for CW Doppler mode imaging and a high voltage for B-mode imaging. This low cost circuitry may simplify and improve the delivery of high voltage in a two or more level power supply selection in ultrasound imaging.

Abstract: Ultrasound apparatus for examining tissue in a region of interest in a body comprising a housing having a viewing aperture. An ultrasonic transducer is provided comprised of an array of ultrasonic elements disposed in the viewing aperture. Electrical pulses are supplied to the transducer for transducer excitation to introduce ultrasonic signals into the body for reflection from the tissue in the region of interest. The transducer is capable of converting ultrasonic signals reflected from the tissue within the body to the transducer to provide electrical signals. The electrical signals are gain corrected in accordance with time. In-phase and out-of-phase components of the electrical signals are provided and then digitized. The digitized electrical signals are collected to form one image for a single frame of the tissue in the region of interest in the body from transducer excitations less than thirty-three in number which is then displayed.

Abstract: An ultrasonic driving apparatus consists mainly of a digital oscillatory circuit, an amplifier, a detection circuit, a phase difference detection circuit, a register, a data transfer circuit, and a switching circuit. The digital oscillatory circuit is used to drive an ultrasonic transducer at the resonance frequency of the ultrasonic transducer. The amplifier amplifies a driving signal output from the digital oscillatory circuit. The detection circuit detects the phase &thgr;v of an applied voltage and the phase &thgr;i of an induced current from the driving signal applied to the ultrasonic transducer via the amplifier. The phase difference detection circuit detects a difference between the phases &thgr;v and &thgr;i. The register holds digital frequency data with which a frequency at which the digital oscillatory circuit is oscillated is determined, and changes the digital frequency data. The data transfer circuit transfers the digital frequency data to the register.

Abstract: A connection union and method for securing together first and second components of an ultrasonic waveguide or blade. The first and second components of the ultrasonic waveguide or blade are formed as complementary components which engage each other with a complementary fitting. Then a compressed fit over the connection union is formed by an electromagnetic metal forming operation which compressively deforms a female coupling member over the connection union. The female coupling member can comprise a separate sleeve which is compressed over the connection union by the electromagnetic metal forming operation. Alternatively, the female coupling member can comprise a terminal end of one of the first and second components which includes a longitudinally extending recess which forms an outer circumferentially extending sleeve which is compressed over the connection union by the electromagnetic metal forming operation.

Abstract: The invention relates to an ultrasonic diagnostic imaging method for determining propagation parameters of transient shear wave front, comprising steps of forming transient shear waves in a tissue (5), acquiring ultrasonic image data (S,S*) of the tissue, along image lines (l), during a time delay (TSW) for a transient shear wave front to propagate over a depth (z) in said tissue, estimating the tissue velocity (V) for each line, constructing a tissue velocity image sequence [I(V)] from the ultrasonic data (S,S*) and the tissue velocities (V) on the lines, and deriving the velocities (CSW) of the shear wave front at instants of the sequence. Tissue parameters such as elasticity are then calculated from said front velocity. The invention also relates to an ultrasonic diagnostic imaging system having processing means (100, PROCESSING1, PROCESSING2) for carrying out this method. The processing means may be a computer program product having instruction to this end.

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: A region of interest (ROI) of a patient's body is repeatedly scanned using an ultrasound transducer array. Data sets representing an image property, such as intensity, from portions of the ROI are used to calculate a representation of the displacement profile within the ROI at different stress levels. From the displacement profile, a function of strain is also preferably calculated. According to one aspect of the invention, a data set representing an estimate of the elasticity profile within the ROI is color-coded and is displayed along with a B-mode display in a single, overlaid display. According to another aspect of the preferred embodiment of the invention, the display of elasticity is adaptively persisted as a function of, for example, a measure of image quality. The invention also provides an on-screen guide that indicates to a user a measure of quality of each of a series of estimated displacement data sets.

Abstract: Spatially compounded images are produced by combining signals from different look directions as a function of the received echo signals. In one embodiment the combinational processing of the echo signals is a function of the steering direction sensitivity of the echo signals. Adaptive variation in the combinational processing can be done on a pixel-by-pixel basis within a particular image, on an image-by-image basis, or in response to the diagnostic exam being performed.

Abstract: Methods and apparatus for producing zones with different contrast agent concentrations in a contrast agent infused target. An aspect of the method is subjecting the target to an ultrasound flash capable of producing first and second target zones, the first target zone having a higher concentration of contrast agent than the second target zone. Another aspect of the method is forming an ultrasound image of the target, wherein the first and second target zones in the ultrasound image have different ultrasonic responses. An embodiment of the apparatus of the present invention comprises a front-end controller (FEC) for use in a medical imaging system wherein the FEC controls a transducer to selectively radiate, in a single frame, a first beam position at a first energy and a second beam position at a second energy.

Abstract: An imaging system and method provides for the automatic leveling of a hologram detector system. A detector system must be precisely oriented in a proper predetermined orientation. The present invention senses the orientation of a plate to which the detector system is mounted and adjusts driver motors to maintain the detector system at a desired predetermined orientation. In an exemplary embodiment, orientation sensors form a feedback loop to a servo controller to control the position of the motors and thus maintain the detector system at the predetermined orientation. In another aspect of the invention, the patient table may be repositioned with respect to the imaging system. The patient is positioned on a table and imaging performed. If an object of interest is detected, the patient table may be independently repositioned in three orthogonal directions such that the object of interest coincides with an axis of rotation of the patient table.

Abstract: Line synthesis avoids artifacts from differences in collateral destruction of contrast agent. Data representing a plurality of scan lines is received in response to each transmit event. Transmission and reception along the same scan lines are repeated a plurality of times for loss correlation imaging. Coherent data or data prior to detection along two or more scan lines is combined, removing differences. The combined data represents a synthesized line of data for detection. Line data representing contrast agents or not representing contrast agents may be synthesized from detected data. Detected data or data in the magnitude and phase domain representing two or more scan lines is combined. By altering the data provided to a flow processor or Doppler data detector, the relative phase of the data representing the two scan lines is determined. A magnitude for a synthetic line is calculated as a function of the magnitude of data representing two separate scan lines and the relative phase.