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 invention relates to an insonification device (100) comprising a plurality of elementary ultrasonic transducers (110) each comprising at least one electro-acoustic element (111) and distributed on a chassis (120, 140) so that the electro-acoustic elements (111) are distributed on a so-called front surface (120?) of the device (100) intended to be placed facing the medium to be insonified. According to the invention, as each transducer (110) comprises a longitudinal body (113) made in a heat conducting material at the so-called front end of which the electro-acoustic element (111) is placed, the chassis (120, 140) comprises a sealed cooling chamber (130) placed behind the front surface (120?), crossed by the bodies of the transducers (113) and intended to be gone through by a coolant fluid flow.

Abstract: The invention concerns a method for optimizing the focusing of waves in a zone of interest of a medium, with the waves being emitted by a network of sources to the medium through an aberration-inducing element that introduces an initially indeterminate phase shift. The method according to the invention proposes to use M?1 successive modifications of the emitted wave, each giving rise to a perturbation. According to the invention, the M perturbations are measured in the zone of interest at each modification of the phase and/or amplitude distributions, and these measurements are used to deduce optimal focusing characteristics to maximize the perturbation induced in the zone of interest.

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.

Abstract: The invention concerns a device (1) for the insonification of an environment or medium, which is designed to generate a beam of focussed waves around a point in a so-called focus zone (20), used for imaging the medium or changing the properties of the medium, with the insonification device (1) having an intrinsic or extrinsic support structure on which is installed a network of a predetermined number of ultrasound transducers (12) that are designed to be controlled independently for generation of the focussed wave beam. According to the invention, the transducers (12) used for the generation of the focussed wave beam are located in a homogeneous spatial distribution along at least two concentric spirals (11) that are wound onto a three-dimensional concave area (10) whose shape and size are chosen to allow optimal focusing of the beam at a predetermined focal length, and whose concave side is oriented toward the focus zone (20).

Abstract: The invention concerns an electronic display system, intended to be coupled with ultrasound imaging equipment capable of capturing an image of a medium, said system comprising a first monitor to display an ultrasound image such as captured by the ultrasound imaging equipment and image processing means.

Abstract: Method for measuring a physical parameter in soft tissues of a mammal, in which a mechanical shear wave is propagated through the soft tissues and observation of the propagation leads to determine values of a shear wave propagation parameter. The physical parameter is computed on the basis of these values.

Abstract: The invention relates to a method of generating a predetermined objective wave field in a medium using a first network of transducers T1-Tn). The inventive method consists in first using each transducer i of the first network to emit an approximation of the signal ei(t). Subsequently, each transducer of a second network of transducers (T?1-T?m) is used to emit an error signal corresponding to the time reversal of the difference between the signals captured from said first emission and objective signals. Finally, approximation ei(t) is corrected by subtracting the time reversal of the signal captured by each transducer i using the error signal.

Abstract: A Method for measuring heart contractility of a patient, in which a mechanical shear wave is propagated through the heart and observation of the propagation leads to determine a shear wave propagation parameter representative of the elasticity of the heart is disclosed. The value of the propagation parameter at the end of a systole is sampled, which leads to a parameter representative of the end systolic elastance.

Abstract: A non-invasive method of obtaining a target soundwave field in the brain by means of an array of transducers positioned outside the skull, the method comprising a training stage during which, on the basis of a three-dimensional image giving the porosity of the skull at all points, digital simulation is used to determine individual sound signals to be emitted by the transducers in order to obtain the target soundwave field in the brain. After the training stage, the array of transducers is used to locate the position of the array of transducers relative to the skull by echography and to ensure that the array of transducers is accurately positioned.

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: Method for rheological characterization of a viscoelastic medium, comprising 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 invention relates to a method and a device for imaging a visco-elastic medium. The method comprises an excitation step during which an internal mechanical stress is generated in excitation zone and an imaging step of acquiring signals during the 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. According to the invention, the method further comprises a step of calculating a quantitative index associated with the rheological properties of the visco-elastic medium at at least one point of the imaging zone situated at a given depth outside the excitation 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: The invention concerns a method for optimizing the focusing of waves in a zone of interest of a medium, with the waves being emitted by a network of sources to the medium through an aberration-inducing element that introduces an initially indeterminate phase shift. The method according to the invention proposes to use M?1 successive modifications of the emitted wave, each giving rise to a perturbation. According to the invention, the M perturbations are measured in the zone of interest at each modification of the phase and/or amplitude distributions, and these measurements are used to deduce optimal focusing characteristics to maximize the perturbation induced in the zone of interest.

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 focussed on an interface (13) delimiting two zones (11, 14) having distinct acoustic properties.