This method, for determining the local intensity (I.sub.0) of an acoustic field propagating in a target region of a soft solid, at a position located within said target region, includes at least the following steps: determining (102) a value of an ultrasound attenuation coefficient (α) of the soft body in the target region; determining (104) a value of the shear modulus (μ) of the soft body in the target region; determining (106) a value of the speed of sound (c) in the target region of the soft body; and building (110), with the values determined in steps a), b) and c), a viscoelastic model (M) of a steady-state displacement induced by an acoustic field having a time invariant shape or a viscoelastic model of a difference between two steady-state displacements induced by an acoustic field having a time invariant shape. Moreover, this method also includes the following steps: applying (112) to the target region the acoustic field emitted by an ultrasound source, for a duration such that the acoustic field induces a steady-state localized deformation (Formula (I)) of the soft body in the target region; measuring (114) at least one steady state displacement induced by the acoustic field at a given position in the target region; and computing (116) the amplitude of the intensity of the acoustic field at said given position by inverting the viscoelastic model (M) at said given position, for the displacement(s) measured at step f).

A shear wave elastography method for imaging an observation field in an anisotropic medium, including an initial ultrasonic acquisition step during which initial physical parameters are acquired in at least one region of interest; a spatial characterization step during which a set of spatial characteristics of the anisotropic medium is determined on the basis of the initial physical parameter; an excitation substep during which an shear wave is generated inside the anisotropic medium on the basis of the set of spatial characteristics; and an observation substep during which the propagation of the shear wave is observed simultaneously at a multitude of points in the observation field.

An ultrasonic method for quantifying the nonlinear shear wave elasticity of a medium, the method comprising the following steps: A1.—collecting a temporal succession of shear wave elasticity data from the medium, A2.—applying, to the medium, a deformation that successively changes according to a predetermined sequence of deformations, during the collection of the shear waves, A3.—observing the actual evolution of deformation, and B.—quantifying the nonlinear elasticity of the medium depending on the temporal succession of data and the evolution of deformation.

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.

The present disclosure describes ultrasound systems and methods configured to determine the elasticity of a target tissue. Systems can include an ultrasound transducer configured to acquire echoes responsive to ultrasound pulses transmitted toward the tissue, which may include a region of increased stiffness. Systems can also include a beamformer configured to control the transducer to transmit a push pulse into the tissue, thereby generating a shear wave in the region of increased stiffness. The beamformer can be configured to control the transducer to emit tracking pulses adjacent to the push pulse. Systems can further include a processor configured to determine a displacement amplitude of the shear wave and based on the amplitude, generate a qualitative tissue elasticity map of the tissue. The processor can combine the qualitative map with a quantitative map of the same tissue, and based on the combination, determine a boundary of the region of increased stiffness.

An ultrasonic diagnostic apparatus includes: a hardware processor that determines a focal position of a push wave, and positions of observation points in a region of interest indicating an analysis target range within the subject, causes the ultrasonic probe to perform transmission of a push wave focusing on the focal position, and subsequent to the transmission, causes the ultrasonic probe to transmit a detection wave passing through the region of interest within the subject, and calculates amounts of displacement of tissue of the subject at the observation points on the basis of a reflected wave obtained by the ultrasonic probe in response to the transmission of the detection wave, calculates propagation speeds of the shear wave in the tissue of the subject with respect to the observation points on the basis of the amounts of displacement, and evaluates values of the propagation speeds calculated to create an evaluation result.

An ultrasonic diagnosis apparatus according to an embodiment includes a transmission unit, a reception unit, a generator, and a display controller. The transmission unit causes an ultrasonic probe to transmit a displacement-producing ultrasonic wave and causes the probe to transmit a displacement-observing ultrasonic wave. The reception unit generates reflected-wave data based on a reflected wave received by the probe. The generator calculates displacement at each of a plurality of positions in the scan area over a plurality of time phases, based on the reflected-wave data, determines a time phase when the calculated displacement is substantially maximum, for each of the positions, and generates image data representing positions where the determined time phases are substantially the same as each other, among the positions. The display controller superimposes an image based on the image data on a medical image corresponding to an area including the scan area.

A system and method from improving the image quality achievable with an ultrasound transducer by using a composite aperture for receiving ultrasound echoes. By using two receive cycles per vector, twice as many transducers may be used for receiving ultrasound imaging data than there are physical channels available in the ultrasound probe. An ultrasound probe utilizing a composite aperture can achieve high image quality from a system have reduced power, size, cost and complexity.

A method for tissue characterization by ultrasound wave attenuation measurements is provided that comprises: a) transmitting at least an ultrasound pulse in a target body; b) receiving ultrasound pulses reflected by the target body and transforming the reflected ultrasound pulses into RF reception signals; c) extracting an envelope of the received RF signals; d) carrying out a logarithmic compression of the extracted envelope and e) computing a propagation depth dependent attenuation coefficient of the tissues crossed by the ultrasound pulse in the target body as the slope of the line fitting the logarithmic compressed envelope data along the penetration depth of the ultrasound pulse in the target body. The disclosure relates also to an ultrasound system for carrying out the method.

An ultrasound diagnosis apparatus includes a two-dimensional (2D) array ultrasound probe configured to emit focused beams onto focusing points and detect echo signals; and a processor configured to determine the focusing points on a cross-section of interest and acquire shear wave elasticity data with respect to the cross-section of interest based on the detected echo signals.