An ultrasonic diagnostic imaging system produces an image of shear wave velocities by transmitting push pulses to generate shear waves. A plurality of tracking lines are transmitted and echoes received by a focusing beamformer adjacent to the location of the push pulses. The tracking lines are sampled in a time-interleaved manner. The echo data acquired along each tracking line is processed to determine the time of peak tissue displacement caused by the shear waves at points along the tracking line, and the times of peaks at adjacent tracking lines compared to compute a local shear wave velocity. The resultant map of shear wave velocity values is color-coded and displayed over an anatomical image of the region of interest.

An ultrasonic diagnostic apparatus to which a probe including a plurality of oscillators is connectable and that causes the probe to transmit a push wave including an ultrasonic beam to focus into an object to be examined, to detect a propagation speed of a shear wave, includes: a push-wave pulse transmitter that supplies a push-wave pulse to each of a plurality of transmission oscillators, to cause the plurality of transmission oscillators to sequentially transmit a plurality of push waves to focus onto a plurality of transmission focuses, a detection-wave pulse transmitter that supplies a detection-wave pulse to part or all of the plurality of oscillators, to cause the plurality of oscillators to transmit a detection wave to pass through a region of interest; and a propagation information analyzer that calculates propagation-speed frame data of a shear wave in the region of interest.

A probe irradiates an ultrasound wave to an object to induce a shear wave and first elasticity information is obtained according to a first calculating scheme. An internal region of interest of the object is set based on shear modulus values included in the first elasticity information. Second elasticity information is obtained based on the shear wave induced to the internal region of interest, according to a second calculating scheme. Accurate elasticity information is acquired by using the first and second elasticity information to obtain third elasticity information from which an elastography image is generated for display to a user.

Acoustic evaluation of a target can be performed using an array of electro-acoustic transducers. For example, a technique for such evaluation can include generating pulses for transmission by respective ones of a plurality of electro-acoustic transducers in a transducer array to contemporaneously establish respective acoustic beams corresponding to at least two different acoustic beam steering directions for an acquisition, the pulses comprising at least a first sequence having pulses of defining a profile having a first polarity, the first sequence corresponding to a first beam steering direction (e.g., angle or spatial beam direction), and a second sequence having pulses defining a profile having a second polarity opposite the first polarity, the second sequence corresponding to a second beam steering direction. In response to transmission of the pulses, respective acoustic echo signals can be received and aggregated to form an image of a region of interest on or within the target.

For clutter reduction in ultrasound elasticity imaging, the contribution of clutter to different frequency components (e.g., the transmit fundamental and the propagation generated second harmonic) is different. As a result, a difference in displacements determined at the different frequency bands is used to reduce clutter contribution to displacements used for elasticity imaging.

A method for measuring a viscoelastic parameter of an organ, includes emitting ultrasonic shots by an ultrasonic transducer; receiving by the transducer and recording the reflected ultrasonic signals; determining a viscoelastic parameter of the organ based on the recorded ultrasonic signals. The ultrasonic shots are formed by K groups of shots, separated temporally, K being greater than or equal to 1. Each K group is formed by the repetition, with a rate of PRF2, of MK blocks of ultrasonic shots, MK being greater than or equal to 1; each MK block is composed of N ultrasonic shots, N being greater than or equal to 1, PRF1 being the rate of emission of the N shots when N is chosen greater than 1; the N ultrasonic shots are distributed over P frequencies, P being between 1 and N, at least two ultrasonic shots belonging to two different blocks having different frequencies.

According to one embodiment, an analysis apparatus includes processing circuitry. The processing circuitry configured to generate a harmonic signal and a fundamental wave signal based on a reception signal that is collected by an ultrasound probe, the harmonic signal corresponding to a harmonic component of a reflected wave of a ultrasound generated in the subject, the fundamental wave signal corresponding to a fundamental wave component of the reflected wave, calculate a first index value indicating tissue properties of the subject based on the harmonic signal, and calculate a second index value indicating the tissue properties based on the fundamental wave signal, and display an analysis result based on the first index value and the second index value.

Three-dimensional elasticity imaging is provided. Motion in three-dimensions due to sources other than the stress or compression for elasticity imaging is found from anatomical information. Objects less likely to be subject to the stress or compression and/or likely to be subject to undesired motion are used to find the undesired motion. This anatomical motion is accounted for in estimating the elasticity, such as removing the motion from echo data used to estimate elasticity or subtracting out the motion from motion generated as part of estimating elasticity.

A method of performing shear wave elastography in tissue includes transmitting successively a series of ultrasound push pulses in the tissue in a region of interest (ROI) using a single array transducer. The acoustic intensities of the push pulses are sinusoidally modulated with a modulation frequency, Each push pulse generates an acoustic radiation force that pushes the tissue and creates an individual shear wave propagating through the tissue. The amplitudes of the shear waves, and therefore, the displacements produced by the push pulses, are positively proportionally to the intensities of the push pulses. The successively created individual shear waves with different amplitudes sum together to form a continuous, harmonic summed shear wave with a single frequency the same as the modulation frequency of the push pulses.

In viscoelastic imaging with ultrasound, the shear wave speed or other viscoelastic parameter is measured by tracking at the ARFI focal or other high-intensity location relative to the ARFI transmission. Rather than tracking the shear wave, the tissue response to ARFI is measured. A profile of displacements over time or a spectrum thereof is measured at the location. By finding a scale of the profile resulting in sufficient correlation with a calibration profile, the shear wave speed or other viscoelastic parameter may be estimated.