Abstract: An elastography device includes a probe, to be held against the body of a subject, the probe including a single ultrasound transducer; or a plurality of ultrasound transducers, all ultrasound transducers of the being motionless with respect to each other, and a low frequency vibrator, arranged to induce a displacement of said single ultrasound transducer or plurality of ultrasound transducers towards a tissue to be characterized, and an electronic unit including an electronic circuit, configured to control the single ultrasound transducer or plurality of ultrasound transducers to emit a sequence of ultrasound pulses in the tissue to be characterized, and configured to acquire echo signals received by the single ultrasound transducer or plurality of ultrasound transducers in response to the ultrasound pulses emitted, in order to track how elastic waves travel in the tissue.

Abstract: A method for determining an index for assessing a cardiac function of a subject, includes performing, by elastography, first and second liver stiffness measurements to obtain first and second values of a liver stiffness parameter of the subject, the first and second values being associated with first and second times; determining, by a processing circuit, the index of the cardiac function based on the first and second values, and outputting, via a graphical user interface of a device, the determined index of the cardiac function of the subject. The first value corresponds to a value of the liver stiffness parameter before or immediately after performing a predetermined cardiac stimulation that modifies a cardiovascular system of the subject and the second value corresponds to a value of the liver stiffness parameter obtained after performing the first liver stiffness measurement.

Abstract: An elastography device includes an electronic unit adapted to determine a plurality of measurements of a mechanical property of a region of a body of a subject, the electronic unit being further adapted to receive a cardiac signal relative to a cardiac activity of the subject, wherein at least one measurement of the mechanical property among the plurality of measurements of the mechanical property is determined upon detection of an event relative to the cardiac signal.

Abstract: A method for measuring viscoelastic properties of a viscoelastic medium, the method including positioning a probe in contact with the viscoelastic medium, the probe extending along a longitudinal axis and being adapted to carry out transient elastography measurements and including a casing, at least one ultrasound a transducer arranged at a tip of the probe and adapted to generate ultrasounds, a force sensor configured to measure a force applied by the tip of the probe, and a vibrator arranged in the casing and adapted to generate a low-frequency wave, measuring a contact force by the force sensor; generating a measurement ready signal by the probe when the measured contact force is higher than a minimum measurement force threshold, and when the measurement ready signal has been generated, triggering a transient elastography measurement.

Abstract: An elastography device comprising: a probe that comprises a protruding part to be applied against the body of a subject, a low frequency vibrator arranged to move the protruding part, at least one ultrasound emitter and one ultrasound receiver; and an electronic unit. The electronic unit is adapted to alternatively control the elastography device so that it operates (a) in a guidance mode to determine whether the probe is correctly positioned in front of a region of the body to be probed to carry out a measurement of a mechanical property of the probed region and (b) in a measurement. In the guidance mode, the vibrator delivers a plurality of successive probing pulses (PRB), each being a transient, low frequency mechanical pulse, and the electronic unit determines a propagation quality indicator (Q) representative of an aptitude of the probed region to transmit the probing pulse.

Abstract: An elastography device to obtain a signal representative of variations of a mechanical property of a region of a body of a subject with time, includes an electronic unit adapted to determine, at a repetition rate of at least 4 measurements per second and for a duration of at least 1 second, measurements of the mechanical property, each measurement being associated with a respective time, wherein the signal representative of the variations of the mechanical property with time includes a plurality of the measurements of the mechanical property determined.

Abstract: An elastography device includes a probe that includes a protruding part to be applied against the body of a subject, a low frequency vibrator arranged to move the protruding part, at least one ultrasound emitter and one ultrasound receiver; and an electronic unit. The electronic unit is adapted to alternatively control the elastography device so that it operates (a) in a guidance mode to determine whether the probe is correctly positioned in front of a region of the body to be probed to carry out a measurement of a mechanical property of the probed region and (b) in a measurement. In the guidance mode, the vibrator delivers a plurality of successive probing pulses (PRB), each being a transient, low frequency mechanical pulse, and the electronic unit determines a propagation quality indicator (Q) representative of an aptitude of the probed region to transmit the probing pulse.

Abstract: A method for measuring viscoelastic properties of a viscoelastic medium, the method including positioning a probe in contact with the viscoelastic medium, the probe extending along a longitudinal axis and being adapted to carry out transient elastography measurements and including a casing, at least one ultrasound a transducer arranged at a tip of the probe and adapted to generate ultrasounds, a force sensor configured to measure a force applied by the tip of the probe, and a vibrator arranged in the casing and adapted to generate a low-frequency wave, measuring a contact force by the force sensor; generating a measurement ready signal by the probe when the measured contact force is higher than a minimum measurement force threshold, and when the measurement ready signal has been generated, triggering a transient elastography measurement.

Abstract: An elastography device includes a probe with a single ultrasound transducer; or a plurality of ultrasound transducers, and a low frequency vibrator arranged to induce a displacement of said single ultrasound transducer or plurality of ultrasound transducers towards a tissue. The device is configured to emit a sequence of ultrasound pulses and to acquire echo signals received in response to track how elastic waves, induced by the displacement, travel in the tissue. The device is configured to generate, for one or more of the ultrasound pulses emitted a temporal offset upon emission, and/or a temporal offset upon reception, so that a difference thereof varies as a function of 2·d/vus, where d is the displacement of the single transducer or plurality of ultrasound transducers, and where vus is the speed of ultrasound in said tissue.

Abstract: A system and method for accumulating ultrasound attenuation data for the detection of disease or other conditions. In one embodiment, an ultrasound system generates a number of imaging pulses during an imaging mode. Echo signals received from the imaging pulses are tested against one or more quality metrics. Attenuation data from the echo signals that pass the quality metrics are accumulated and are used to compute a tissue characteristic. In one embodiment the tissue characteristic is a CAP measurement that is related to an amount of fat in a liver.

Abstract: A method for measuring an ultrasonic attenuation parameter guided by harmonic elastography including applying, using a vibrator included in a probe in contact with a viscoelastic medium, of a continuous low frequency vibration, the continuous low frequency vibration generating an elastic wave within the viscoelastic medium and generating, during the propagation of the elastic wave, using an ultrasonic transducer in contact with the viscoelastic medium, a series of ultrasonic acquisitions, the series of ultrasonic acquisitions including groups of ultrasonic acquisitions, the groups of ultrasonic acquisitions being generated with a repetition rate, each group of ultrasonic acquisitions including at least one acquisition; the ultrasonic attenuation parameter being measured from the ultrasonic acquisitions realised during the application of the continuous low frequency vibration.

Abstract: An elastography device includes a probe, to be held against the body of a subject, the probe including a single ultrasound transducer; or a plurality of ultrasound transducers, all ultrasound transducers of the being motionless with respect to each other, and a low frequency vibrator, arranged to induce a displacement of said single ultrasound transducer or plurality of ultrasound transducers towards a tissue to be characterized, and an electronic unit including an electronic circuit, configured to control the single ultrasound transducer or plurality of ultrasound transducers to emit a sequence of ultrasound pulses in the tissue to be characterized, and configured to acquire echo signals received by the single ultrasound transducer or plurality of ultrasound transducers in response to the ultrasound pulses emitted, in order to track how elastic waves travel in the tissue.

Abstract: A method for measuring viscoelastic properties of a viscoelastic medium, the method including positioning a probe in contact with the viscoelastic medium, the probe extending along a longitudinal axis and being adapted to carry out transient elastography measurements and including a casing, at least one ultrasound a transducer arranged at a tip of the probe and adapted to generate ultrasounds, a force sensor configured to measure a force applied by the tip of the probe, and a vibrator arranged in the casing and adapted to generate a low-frequency wave, measuring a contact force by the force sensor; generating a measurement ready signal by the probe when the measured contact force is higher than a minimum measurement force threshold, and when the measurement ready signal has been generated, triggering a transient elastography measurement.

Abstract: An elastography device comprising: a probe that comprises a protruding part to be applied against the body of a subject, a low frequency vibrator arranged to move the protruding part, at least one ultrasound emitter and one ultrasound receiver; and an electronic unit. The electronic unit is adapted to alternatively control the elastography device so that it operates (a) in a guidance mode to determine whether the probe is correctly positioned in front of a region of the body to be probed to carry out a measurement of a mechanical property of the probed region and (b) in a measurement. In the guidance mode, the vibrator delivers a plurality of successive probing pulses (PRB), each being a transient, low frequency mechanical pulse, and the electronic unit determines a propagation quality indicator (Q) representative of an aptitude of the probed region to transmit the probing pulse.

Abstract: A transient elastography probe includes a probe body; an ultrasound transducer configured to generate an ultrasound beam along an axis, the ultrasound beam being generated from a face of the ultrasound transducer; a vibrator located inside the probe body and arranged so as to induce a movement of the ultrasound transducer along a predefined axis; the ultrasound transducer being mounted on the vibrator so that the predefined axis and the axis of the ultrasound beam coincide with each other, and a sealing membrane hugging the outer contours of the ultrasound transducer.

Abstract: A method for measuring viscoelastic properties of a viscoelastic medium, the method including positioning a probe in contact with the viscoelastic medium, the probe extending along a longitudinal axis and being adapted to carry out transient elastography measurements and including a casing, at least one ultrasound a transducer arranged at a tip of the probe and adapted to generate ultrasounds, a force sensor configured to measure a force applied by the tip of the probe, and a vibrator arranged in the casing and adapted to generate a low-frequency wave, measuring a contact force by the force sensor; generating a measurement ready signal by the probe when the measured contact force is higher than a minimum measurement force threshold, and when the measurement ready signal has been generated, triggering a transient elastography measurement.

Abstract: A device for vibration controlled transient elastography, in particular to quantify liver fibrosis, includes an ultrasound probe for elastography comprising a probe casing, at least one ultrasound transducer having a symmetry axis, a vibrator, and a force sensor, wherein the vibrator is arranged to induce a movement of the probe casing along the symmetry axis of the ultrasound transducer, the ultrasound transducer being bound to the probe casing with no motion of the ultrasound transducer relative to the probe casing, and wherein the device includes a signal generator configured to issue a contact ready signal when the force applied by the probe on the to-be-measured viscoelastic medium is greater than a minimum contact force threshold. The signal generator may further be configured to issue a measurement ready signal when the force is greater than a minimum measurement force threshold.

Abstract: 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.

Abstract: A method for measuring viscoelastic properties of a viscoelastic medium, the method including positioning a probe in contact with the viscoelastic medium, the probe extending along a longitudinal axis and being adapted to carry out transient elastography measurements and including a casing, at least one ultrasound a transducer arranged at a tip of the probe and adapted to generate ultrasounds, a force sensor configured to measure a force applied by the tip of the probe, and a vibrator arranged in the casing and adapted to generate a low-frequency wave, measuring a contact force by the force sensor; generating a measurement ready signal by the probe when the measured contact force is higher than a minimum measurement force threshold, and when the measurement ready signal has been generated, triggering a transient elastography measurement.

Abstract: 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.