Acuson Corporation

Siemens Medical Solutions Usa, Inc.

Charles E Bradley

Kutay F Ustuner

David J Napolitano

Patrick J Phillips

John Alexander Hossack

Samuel H Maslak

Gregory L Holley

David J Hedberg

Christopher R Cole

Lewis J Thomas

Daniel E Need

Bhaskar S Ramamurthy

John W Allison

Thilaka S Sumanaweera

Linyong Pang

Paul Anthony Wagner

Ching-Hua Chou

Danhua Zhao

Stuart L Carp

Christopher M Daft

Rickard C Loftman

Timothy L Proulx

Stirling S Dodd

Lawrence J Newell

Dave Napolitano

Ken Sawatari

Igal Ladabaum

Walter T Wilser

Seshadri Srinivasan

Satchi Panda

Jian-Hua Mo

J Paul Mohr

Using parallel receive beamformation, sets of data representing locations in at least a common field of view are obtained, each set in response to a transmit with a spatially distinct phase front. The common field of view receive data are time aligned and amplitude weighted for retrospective transmit focusing and retrospective transmit apodization, respectively. A time offset is applied to the receive data for retrospective transmit focusing. The offset is selected to emulate shifting the transmit delay profile to be tangentially intersecting with the dynamic receive delay profile for each location which is the desired transmit delay profile. A weight is applied to the receive data for retrospective transmit apodization. The offset and weighted data representing a same location from different transmit events is coherently combined. The number of sets of data offset, weighted and combined may vary as a function of depth for dynamic transmit beamformation.

Coherent image formation for dynamic transmit beamformation

An ultrasound imaging system may use a capacitive membrane or electrostrictive ultrasound transducer to realize isotropic volumetric imaging with bias-line element selection and a variety of aperture synthesis techniques. Two dimensional beam formation may be performed by using a beamformer to focus along one dimension, and then perform a second round of 'off-line' or 'retrospective' beam formation along the other direction.

Aperture synthesis using cMUTs

Retrospective dynamic transmit beamformation is provided in medical ultrasound imaging. Using parallel receive beamformation, sets of data representing locations in at least a common field of view are obtained, each set in response to a transmit with a spatially distinct phase front. The common field of view receive data are time aligned and amplitude weighted for retrospective transmit focusing and retrospective transmit apodization, respectively. A time offset, such as of a cycle or more in some cases, is applied to the receive data for retrospective transmit focusing. The offset is selected to emulate shifting the transmit delay profile to be tangentially intersecting with the dynamic receive delay profile for each location which is the desired transmit delay profile. A weight is applied to the receive data for retrospective transmit apodization. The weight is selected based on the desired transmit apodization profile. The offset and weighted data representing a same location from different transmit events is coherently combined. The number of sets of data offset, weighted and combined may vary as a function of depth for dynamic transmit beamformation.

Synthetic transmit aperture is provided for three-dimensional ultrasound imaging. A transducer may have separate transmit and receive elements. Broad beams are transmitted, allowing fewer transmit elements and/or more rapid scanning. A multidimensional receive array generates data in response to sequential transmissions, such as transmissions from different angles. The data is combined to increase resolution. A transducer array with offset transmit elements for forming a transmit line source may be used.

Ultrasound imaging transducer array for synthetic aperture

A method is provided to improve the frame-rate in color-flow ultrasound imaging using simultaneous spatially-distinct transmit beams with one or more frequency bands per transmit beam. Pulses of different center frequencies are used simultaneously in different (lateral and/or elevational) directions, thereby reducing the scanning time and improving the frame-rates. Optionally, a multi-modal pulse is used, and flow is estimated separately for the different frequencies. The flow estimates for these pulses are appropriately combined to improve low-velocity sensitivity and to reduce aliasing. A flow sample count with two or more different pulse repetition intervals can be used to further improve low-flow sensitivity and minimize aliasing.

Ultrasound color flow imaging at high frame rates

A medical diagnostic ultrasound transducer system has at least a first and a second set of transducer layers of an element. Each set has one or more transducer layers with independent electrical access. A transmit event through a first set of transducer layers with broadband electrical signals generates acoustic signals containing at least two different frequency bands, and a receive event through a second and different set of transducer layers receives multiple tissue harmonic signals to generate a wide bandwidth response. Fundamental signals can be reduced with a pulse inversion technique through a second transmit event of inverted pulses, a second receive event and superposition of signals from the two receive events.

Medical diagnostic ultrasound transducer system for harmonics

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.

Diagnostic ultrasound imaging method and system with improved frame rate

Improvements to a method for imaging a target, which method including the steps of (a) transmitting ultrasonic energy at a fundamental frequency, (b) receiving reflected ultrasonic energy at a harmonic of the fundamental frequency and (c) generating an image responsive to reflected energy at the harmonic, are provided. The transmitting step includes transmitting a waveform with a positive pulse spatially defined by first and second zero values. A positive peak amplitude of the positive pulse is a first distance from the first zero value that is less than half a second distance between said first and second zero values. Thus, the waveform includes a fundamental spectral component and a harmonic spectral component at the transducer. An attenuation normalized peak of the harmonic spectral component is reduced at a region spaced from the transducer as compared to the peak at a region adjacent to the transducer. A negative peak is also shifted or pre-distorted. Various pre-distortions of the waveform may compensate for propagation, scattering, or system non-linearities.

Ultrasonic harmonic imaging system and method using waveform pre-distortion

A medical diagnostic ultrasound imaging system aligns substantially co-planar two-dimensional images to form an extended field of view using improved compounding methods. Compounding with a finite impulse response is used for more versatile compositing. The compounding is adaptive, such as through adapting the image regions, weighting, or type of compounding as a function of correlation, location within the image, estimated motion or combinations thereof. A user warning is provided as a function of the correlation between images.

Medical diagnostic ultrasound imaging methods for extended field of view

A pulse echo beamforming system generates high spatial bandwidth ultrasound images using only a few transmit/receive events per frame. Each transmit/receive event consists of firing an unfocused or weakly focused wave and receiving and storing the echo on every receive channel. Each set of stored echoes is delayed and apodized to form component beams for each desired image point in the region insonified by that particular wave. The final images are synthesized by adding two or more of the component beams for each image point.

Method and apparatus for forming medical ultrasound images

A medical imaging system provides increased detectability of targets such as membranes, tendons, muscle fibers and biopsy needles that have strong directional responses. This improved result is achieved by compounding multiple images generated by using only one or two transducer firings per ultrasound line. Speckle variance is also reduced as the result of spatial compounding, and this reduction improves the detectability of soft-tissue lesions.

Medical ultrasonic imaging method and system for spatial compounding

A medical ultrasonic imaging method uses transmitted plane waves, or transmitted wavefronts that are substantially planar, to improve contrast agent imaging by generating peak pressures that are more uniform over depth. Depending on the type of contrast agent, the returned frequencies of interest, and the desired strength of the non-linear response, multiple wavefronts can be generated at substantially the same time to increase peak pressures.

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Burlingame, CA, United States of America

Charles E Bradley