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: 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: An ultrasonic system for detecting a fluid flow in an environment includes a probe configured for ultrasonic insonification of the environment and reception of an echo signal. The system also includes a control device configured to construct a series of images based on the signal received from the echoes. The images are filtered by a temporal high-pass filter. A local displacement of the flow between two successive images is determined by maximizing the similarity between blocks extracted from the two images.

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: A method for characterizing ultrasound scatterers in a medium comprising providing ultrasound data representing a region of interest comprising a plurality of scatterers in a medium, the plurality of scatterers including clusters of scatterer sub-units, the scatterers having a physical property value to be estimated and the scatterer sub-units having at least one known physical parameter value; modelling the ultrasound data using an at least second order function of a spatial organization parameter defining the spatial organization of the scatterers; and estimating the physical property value of the scatterers from the modelled ultrasound data and the at least one known physical parameter of the sub-units by a regression of the spatial organization parameter as a function of frequency. A system for characterizing ultrasound scatterers is also included.

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: 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: A system for the determination of optical coefficients in an object including an ultrasonic scanner for recording first and second pulse echoes before and after the object has been illuminated with a heating light beam from a light source. An evaluation unit determines a map of temperature increase caused by the heating light beam inside the object based on apparent displacements showing up between the second and first pulse echoes.

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: A method for characterizing ultrasound scatterers in a medium comprising providing ultrasound data representing a region of interest comprising a plurality of scatterers in a medium, the plurality of scatterers including clusters of scatterer sub-units, the scatterers having a physical property value to be estimated and the scatterer sub-units having at least one known physical parameter value; modelling the ultrasound data using an at least second order function of a spatial organization parameter defining the spatial organization of the scatterers; and estimating the physical property value of the scatterers from the modelled ultrasound data and the at least one known physical parameter of the sub-units by a regression of the spatial organization parameter as a function of frequency. A system for characterizing ultrasound scatterers is also included.

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: Methods and systems are provided for monitoring and regulating radiofrequency (RF) ablation therapy to improve quality of ultrasound imaging. Feedback is provided from real-time ultrasound imaging, and RF power is altered in response to a feedback signal to improve image quality.

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 examination apparatus and a method for the determination of optical coefficients, particularly of the optical absorption coefficient (?a) in an object (1) like the body of a patient. The apparatus comprises an ultrasonic scanner (20) for recording first and second pulse echoes before and after the object (1) has been illuminated with a heating light beam (11) from a (e.g. laser) light source (10). An evaluation unit (30) determines a map of temperature increase (?T(r)) caused by the heating light beam (11) inside the object (1) based on apparent displacements showing up between the second and first pulse echoes. Furthermore, the evaluation of locally adjacent temperature increases inside the object (1) allows to determine a map of the effective scattering coefficient (?eff(r)), from which the distribution of light intensity (I(r)) inside the object (1) can be calculated.

Abstract: A method and system of magnetic hyperthermia control using ultrasound thermometry, the method comprising: acquiring a reference set of ultrasound data corresponding to a tissue of interest (121); applying a plurality of magnetic nanoparticles (210) at the tissue of interest (121); applying an electromagnetic field based on a set of operating parameters to initiate the hyperthermia; acquiring another set of ultrasound data corresponding to the tissue of interest (121); and determining a temperature change based on the reference set of ultrasound data and the other set of ultrasound data.

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.