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.

A system for characterizing tissue includes a probe that delivers a continuous and periodic mechanical vibration to a tissue of a subject; an ultrasound emitter that emits a sequence of ultrasound shots and an ultrasound receiver that receives corresponding echo signals to track how the tissue is moved by the periodic mechanical vibration delivered to the tissue; and a control module programmed to provide homogeneity information to an operator of the system, the homogeneity information being determined from at least some of the echo signals and being representative of the ability of the tissue to transmit elastic waves and of the homogeneity of the tissue with respect to the propagation of elastic waves.

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 diagnostic apparatus includes an ultrasound probe, a reference image holding unit that holds an ultrasound image acquired by fixing a position of the ultrasound probe as a reference image, a movement vector calculation unit that calculates a movement vector between two ultrasound images, a movement vector integration unit that integrates the movement vector from a time when the reference image is held to a current time, a deformed image generation unit that generates a deformed image in which the current ultrasound image is moved and changed to a time when the reference image is held based on an integration result, a tomographic plane determination unit that compares the deformed image with the reference image to determine whether tomographic planes of the current ultrasound image and the reference image are the same as each other, and a determination result notification unit that notifies a user of a determination result.

Because of the increase of the obesity related diseases, it is desirable to be able to detect a fatty liver and quantify the content in fat for the fatty liver. Known methods are biopsy and magnetic resonance imaging. However, biopsy is an invasive method and magnetic resonance imaging is a complicated method to carry out. The inventors propose a new ultrasonic method which is more compliant with a regular control of the content in fat for the fatty liver for a subject. This method notably relies on a smart exploitation of the coherence properties of ultrasound pulses applied to the liver. This method has already been validated on sane subjects as providing accurate measurements, notably for fat content.

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.

The power supply in ultrasound imaging includes a switched capacitance. The capacitance is switched on to provide power during generation of pushing pulses for elasticity imaging and is switched off during other modes of imaging.

A system for characterizing tissue includes a probe that delivers a continuous and periodic mechanical vibration to a tissue of a subject; an ultrasound emitter that emits a sequence of ultrasound shots and an ultrasound receiver that receives corresponding echo signals to track how the tissue is moved by the periodic mechanical vibration delivered to the tissue; and a control module programmed to provide homogeneity information to an operator of the system, the homogeneity information being determined from at least some of the echo signals and being representative of the ability of the tissue to transmit elastic waves and of the homogeneity of the tissue with respect to the propagation of elastic waves.

Disclosed are an ultrasonic viscoelasticity measuring method, an apparatus and a storage medium. The method comprises: outputting a first transmitting/receiving sequence to a transducer of an ultrasonic probe to control the transducer to transmit a first ultrasonic wave to a target object and acquire a first ultrasonic echo signal; generating and displaying an ultrasonic image based on the first ultrasonic echo signal and acquiring a region of interest on the ultrasonic image; outputting different drive signals to a vibrator of the ultrasonic probe to perform viscoelasticity measurement, and exerting various mechanical vibrations on the target object by the transducer driven by the vibrator based on at least two different vibration signals; outputting a second transmitting/receiving sequence to the transducer to control the transducer to transmit a second ultrasonic wave to the region of interest to acquire a second ultrasonic echo signal; and acquiring and displaying elasticity parameter(s) and viscosity parameter(s) of the region of interest based on the second ultrasonic echo signal of the region of interest under the various mechanical vibrations. The proposed scheme can effectively improve the accuracy and stability of measured result.

System and method for shear wave elasticity imaging perform a) acquiring B-mode ultrasound images of a target region; b) selecting a region of interest; c) transmitting a shear wave excitation pulse; d) measuring displacements of tracking focal points or depth ranges at different depths positions along each of laterally staggered tracking lines within the selected region of interest; e) determining a curve representing displacement of tissue as a function of time at different spatial locations within the region of interest; f) determining for spatial locations candidate time(s) of arrival of the shear wave at the spatial location as a function of the curve; g) finding linear functional relation between the time of arrival and the spatial coordinate in the lateral direction using Random Sample Consensus (RANSAC) algorithm; and h) determining the inverse of velocity of the shear wave in a spatial location as the angular coefficient of the linear function.