Abstract: 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.

Abstract: 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.

Abstract: The method includes excitation during which an internal mechanical stress is generated in an excitation zone, and imaging by acquiring signals during movements generated by the mechanical stress in the visco-elastic medium in response to the internal mechanical stress in an. imaging zone that includes the excitation zone. The method further includes calculating a quantitative index associated with the rheological properties of the visco-elastic medium at least at one point of the imaging zone situated at a given depth outside the excitation zone. The quantitative index is representative of a comparison between signals acquired during the movements generated in response to the mechanical stress at least at one point of the excitation zone situated at the given depth, and signals acquired during the movements generated in response to the mechanical stress at at least the point of the imaging zone situated outside the excitation zone.

Abstract: 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.

Abstract: 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.

Abstract: The invention relates to a method and a device for imaging a visco-elastic medium [2]. The method comprises the steps of excitation during which an internal mechanical stress is generated in an excitation zone [A]; and imaging by acquiring signals during movements generated by the mechanical stress in the visco-elastic medium [2] in response to the internal mechanical stress in an imaging zone [B] that includes the excitation zone [A]. According to the invention said method further comprises a step of calculating a quantitative index [Cij] associated with the rheological properties of the visco-elastic medium [2] at at least one point [Bij] of the imaging zone [B] situated at a given depth outside the excitation zone [A].

Abstract: The invention relates to a method and a device for imaging a visco-elastic medium (2). The method comprises an excitation step during which an internal mechanical stress is generated in an excitation zone [A] and an imaging step of acquiring signals during the movements generated by the mechanical stress in the visco-elastic medium (2) in response to the internal mechanical stress in an imaging zone [B] that includes the excitation zone [A]. According to the invention, the method further comprises a step of calculating a quantitative index [Cij] associated with the rheological properties of the visco-elastic medium (2) at at least one point [Bij] of the imaging zone situated at a given depth outside the excitation zone [A].

Abstract: A method for measuring a mean visco-elasticity value for a soft material uses a single probe carrying at least one transducer. At least one burst of mechanical vibrations is induced in a constraint zone in order to generate internal shear waves in the tissue propagating from the constraint zone into the tissue. The transient tissue displacements are measured with a transducer in at least one first measurement zone in the tissue, the first measurement zone being located away from the constraint zone. A mean visco-elasticity of the region of the tissue situated between the constraint zone and the first measurement zone is estimated from the measured transient tissue displacements of the tissue in the first measurement zone.

Abstract: The invention relates to a method for measuring a mean visco-elasticity value for a soft material. Said method using a single probe carrying at least one transducer comprises the steps of: a) inducing, in a constraint zone, at least one burst of mechanical vibrations in order to generate internal shear waves in the tissue propagating from said constraint zone into the tissue, b1) measuring, with said transducer, the transient tissue displacements in at least one first measurement zone in the tissue, said first measurement zone being located away from said constraint zone, c) estimating a mean visco-elasticity of the region of the tissue situated between the constraint zone and the first measurement zone from said measured transient tissue displacements of the tissue in the first measurement zone.

Abstract: The invention relates to an ultrasonic imaging probe for imaging a medium (10), comprising two types of transducers, characterized in that the first type of transducer(s) (1) is dedicated to ultrasonic imaging of the medium (10), and the second type of transducer(s) (2) is dedicated to generating a stress producing at least one transient modification of the imaged medium (10), both types of transducer(s) (1, 2) being able to operate at least in a so-called coupled mode where the first type of transducer(s) (1) operates in a synchronized way with the second type of transducer(s) (2) so as to image the time course of the transient modification of the medium (10).

Abstract: An ultrasound imaging method for generating a visualization image includes an emission and reception step of interleaved ultrasound waves, a processing step during which the received sequences are processed for generating three images via three different process, an image combining step during which the visualization image is determined by combining the three images for simultaneously visualizing the results of all images process.

Abstract: The inventive imaging method consists in generating a mechanical wave having shearing and compressional components in a viscoelastic medium and in determining the movement parameter of said viscoelastic medium at different points during the propagation of said mechanical wave. Said method comprises a correction stage when the movement parameter is processed for eliminating errors caused by the compressional component of the mechanical wave.

Abstract: 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.

Abstract: An imaging method using shear waves for observing a viscoelastic medium, comprising: several successive excitation steps j during which elastic shear waves are generated respectively at different excitation loci (Lj) in the viscoelastic medium by an imaging device, the different excitation loci being separated from one another by a maximum distance Dm, an imaging step corresponding to each excitation step j, in which a set j of successive raw images Imj(tk) of the viscoelastic medium at times tk are determined during propagation of the shear wave, the raw images having a resolution R which is larger than the maximum distance Dm, an averaging step in which raw images Imj(tk) corresponding to the same relative time tk are averaged to determine an average image Im?(tk).

Abstract: A method for ultrasound imaging is provided. The method includes at least a transmission step, a coherence enhancing step, and a beamforming step. In the transmission step, a plurality of ultrasonic waves are transmitted into an imaged region and a set of raw data is acquired by an array of transducers in response to each ultrasonic wave. The ultrasonic waves have different spatial frequency content. In the coherence enhancing step, for each of a plurality of virtual transmit focal zones in the imaged region, at least one set of coherent data is synthesized from the sets of raw data. In the beamforming step, for each of a plurality of locations included in each of the virtual transmit focal zones, an image pixel is computed by beamforming, using the set of coherent data.

Abstract: The invention relates to a method for measuring a mean visco-elasticity value for a soft material. Said method using a single probe carrying at least one transducer comprises the steps of: a) inducing, in a constraint zone, at least one burst of mechanical vibrations in order to generate internal shear waves in the tissue propagating from said constraint zone into the tissue, b1) measuring, with said transducer, the transient tissue displacements in at least one first measurement zone in the tissue, said first measurement zone being located away from said constraint zone, c) estimating a mean visco-elasticity of the region of the tissue situated between the constraint zone and the first measurement zone from said measured transient tissue displacements of the tissue in the first measurement zone.

Abstract: The invention relates to a method for measuring a mean visco-elasticity value for a soft material. The method uses a single probe carrying at least one transducer and includes the steps of: (a) inducing, in a constraint zone, at least one burst of mechanical vibrations in order to generate internal shear waves in the tissue propagating from the constraint zone into the tissue, (b1) measuring, with the transducer, the transient tissue displacements in at least one first measurement zone in the tissue, and wherein the first measurement zone is located away from the constraint zone, and (c) estimating a mean visco-elasticity of the region of the tissue situated between the constraint zone and the first measurement zone from the measured transient tissue displacements of the tissue in the first measurement zone.

Abstract: An imaging method using shear waves for observing a viscoelastic medium, comprising: several successive excitation steps j during which elastic shear waves are generated respectively at different excitation loci (Lj) in the viscoelastic medium by an imaging device, the different excitation loci being separated from one another by a maximum distance Dm, an imaging step corresponding to each excitation step j, in which a set j of successive raw images Imj(tk) of the viscoelastic medium at times tk are determined during propagation of the shear wave, the raw images having a resolution R which is larger than the maximum distance Dm, an averaging step in which raw images Imj(tk) corresponding to the same relative time tk are averaged to determine an average image Im?(tk).

Abstract: Method for rheological characterization of a viscoelastic medium, with the following steps: (a) an excitation step during which a vibratory excitation is generated in the viscoelastic medium leading to a deformation of the medium, (b) a deformation measurement step during which the deformation of the medium caused by the excitation is observed, (c) and a characterization step during which at least one non-zero power parameter y is determined such that a rheological parameter of the medium x is equal to x(f)=a+b·fy, where f is the frequency, a is a real number and b a non-zero scale parameter. It is thus possible to obtain mapping of the power parameter y.

Abstract: The present invention relates to a method for generating mechanical waves within a viscoelastic medium (11) comprising a step of generating an acoustic radiation force (15) within the viscoelastic medium (11) by application of acoustic waves focused on an interface (13) delimiting two zones (11, 14) having distinct acoustic properties.