G01S7/52022

Ultrasonic shear wave imaging with background motion compensation
11364015 · 2022-06-21 · ·

An ultrasonic diagnostic imaging for analyzing shear wave characteristics utilizes a background motion compensation subsystem which acts as a spatial filter of pulse-to-pulse autocorrelation phases over the ROI of tracking pulse vectors to compensate for background motion. The subsystem is configured to compute the sum of all lag-1 autocorrelations of tracking line ensemble data over the tracking ROI, for each PRI. The inventive technique does not significantly reduce sensitivity to shear waves, because the shear wave is spatially smaller than the ROI.

Systems and methods for ultrafast ultrasound imaging

A method in accordance with the present disclosure may include transmitting a plurality of ultrasound pulses toward a medium from a transducer array, wherein the plurality of ultrasound pulses includes a sequence of a Doppler burst (10-1, 10-2) comprising a plurality of unfocused first pulses (12) and a B-mode burst comprising one or more second pulses (13). The method may further include detecting echoes responsive to the transmitted sequence, wherein the detecting includes simultaneously detecting, within a field of view, FOV, of the array, a set (14-1, 14-2) of first echoes responsive to the plurality of unfocused first pulses (12), generating Doppler data from signals representative of the set (14-1, 14-2) of first echoes, generating B-mode image data from signals representative of echoes responsive to the one or more second pulses (13), and simultaneously displaying the Doppler data and B-mode image data.

Using reflected shear waves for monitoring lesion growth in thermal ablations

A system for boundary identification includes a memory (42) to store shear wave displacements through a medium as a displacement field including a spatial component and a temporal component. A directional filter (206, 208) filters the displacement field to provide a directional displacement field. A signal processing device (26) is coupled to the memory to execute a boundary estimator (214) to estimate a tissue boundary in a displayed image based upon a history of the directional displacement field accumulated over time.

Intelligent guided wave elastography

The present disclosure describes systems and methods configured to determine shear wave velocity and tissue stiffness levels of thin tissue of finite size, also referred to as bounded tissue, via shear wave elastography. Systems can include an ultrasound transducer configured to acquire echoes responsive to pulses transmitted toward a tissue. Systems can also transmit a push pulse into the tissue for generating shear waves, and tracking pulses intersecting the shear waves. The system can also apply a directional filter to received echo data and generate directionally filtered shear wave data based on a dimension and angular orientation of the bounded target relative to the ultrasound transducer. The system can estimate velocities of the shear waves at different shear wave frequencies based on the filtered shear wave data and angular orientation relative to the transducer, and determine a tissue stiffness value independent of the shape or form of the tissue.

SHEAR WAVE ELASTROGRAPHY METHOD AND APPARATUS FOR IMAGING AN ANISOTROPIC MEDIUM
20230263504 · 2023-08-24 ·

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.

AN ULTRASOUND SYSTEM

An ultrasound system comprising a probe adapted for emitting and receiving ultrasound waves inside a medium, and a processing unit connected to said probe and adapted for processing signals from the probe. The probe is configured so as to behave as a Fresnel lens for focusing the ultrasound waves. The processing unit analyses signals from the probe for sensing the medium at a plurality of focal points.

ULTRASONIC IMAGING APPARATUS AND METHOD FOR CONTROLLING THE SAME
20220125412 · 2022-04-28 ·

Provided is an ultrasonic imaging apparatus capable of obtaining a more accurate shear wave elastic image by removing inefficient areas such as blood vessels using a shear wave observation signal in a section where an object is not affected by a push pulse, and a method for controlling the same. The ultrasonic imaging apparatus according to an embodiment includes: an ultrasonic probe configured to irradiate a push pulse to generate a shear wave to an object, irradiate a first observation signal to the object after the push pulse is irradiated, and irradiate a second observation signal to the object before the push pulse is irradiated or after the first observation signal is irradiated; a controller configured to determine an inefficiency region of the object based on displacement data for each region of the object obtained from the irradiated second observation signal, and generate a shear wave elastic image based on the determined inefficiency region and displacement data for each region of the object obtained from the irradiated first observation signal; and a display configured to display the generated shear wave elastic image.

Motion independence in acoustic radiation force impulse imaging

Motion independent acoustic radiation force impulse imaging is provided. Rather than rely on the displacement over time for each location, the displacements over locations for each time are used. Parallel beamforming is used to simultaneously sample across a region of interest. Since it may be assumed that the different locations are subjected to the same motion at the same time, finding a peak displacement over locations for each given time provides peak or profile information independent of the motion. The velocity or other viscoelastic parameter may be estimated from the displacements over locations.

Ultrasound system

An ultrasound system comprising a probe adapted for emitting and receiving ultrasound waves inside a medium, and a processing unit connected to said probe and adapted for processing signals from the probe. The probe is configured so as to behave as a Fresnel lens for focusing the ultrasound waves. The processing unit analyses signals from the probe for sensing the medium at a plurality of focal points.

Asymmetry for acoustic radiation force impulse

Asymmetry is provided for the pushing pulse in acoustic radiation force impulse (ARFI) imaging. MI is based on the negative pressure. By increasing the positive pressure more than the negative pressure, the magnitude of displacement may be increased without exceeding the MI limit. Similarly, negative voltages depole while positive do not, so using an ARFI or pushing pulse with asymmetric positive-to-negative peak pressures or voltages allows for generation of greater magnitude of displacement without harm to the transducer.