WO2020006812A1

WO2020006812A1 - Method and device for measuring mechanical property parameters of tissue

Info

Publication number: WO2020006812A1
Application number: PCT/CN2018/099966
Authority: WO
Inventors: 张新宇; 邵梦; 朱莹; 陈昕; 刁现芬
Original assignee: 深圳大学
Priority date: 2018-07-06
Filing date: 2018-08-10
Publication date: 2020-01-09
Also published as: CN109077754B; CN109077754A

Abstract

A method and a device (100) for measuring mechanical property parameters of tissue. A data acquisition step (10) is continuously performed multiple of times, said step comprising: controlling an ultrasonic probe (101) to transmit an ultrasonic wave to target tissue (108), and receiving an echo of the ultrasonic wave to obtain first echo data; controlling the ultrasound probe (101) to transmit a focusing acoustic beam to a region of interest of the target tissue (108), so as to generate a propagation of a strain wave; within a resting time after the focusing acoustic beam is transmitted, the ultrasound probe (101) not transmitting an ultrasound signal to and/or receiving an ultrasound signal from the target tissue (108); after the resting time ends, controlling the ultrasonic probe (101) to transmit an ultrasonic wave to the region of interest of the target tissue (108) again, and to receive the echo of the ultrasonic wave, so as to obtain second echo data. The mechanical property parameters of the target tissue (108) are calculated on the basis of multiple sets of first echo data and second echo data. By means of said method and device (100), the temporal resolution for measurement can be several times that of the single excitation detection method in the original technology, achieving accurate detection of wave velocity of a strain wave of biological soft tissue having high toughness.

Description

Method and equipment for measuring mechanical parameters of tissue

Technical field

The present invention relates to a tissue detection method and system, and in particular, to a method and equipment for measuring mechanical parameters of tissue.

Background technique

Medical ultrasound imaging has become one of the mainstream medical imaging methods due to its advantages such as real-time, no radiation, and low price. Among them, ultrasound elastic imaging technology, which mainly measures the mechanical properties of various materials, has become one of the ultrasonic technologies. Huge branches. Strain wave (also known as elastic wave) is a wave type that can only propagate in a solid medium. During the propagation process, the vibration direction and the propagation direction of the particle are perpendicular to each other. Because of the different propagation media, different types of strain waves will be generated when the tissue is stimulated. Strain waves generated when tissues with purely infinite elasticity, such as breasts and livers, are called shear waves; when strain waves propagate in a thin plate-shaped medium (such as blood vessel walls, cornea, bladder, etc.), they are reflected within the boundary of the medium The strong influence of the formation of guided waves. The propagation mode of elastic waves in infinitely thin plates is named Lamb waves. Lamb waves have been widely used in the study of guided wave propagation in cylindrical shells. Strain waves propagating along the free surface of a semi-infinite elastic medium are called Rayleigh waves, which are the superposition of shear waves and longitudinal waves, and can only propagate on solid surfaces. The propagation characteristics of strain waves (including shear waves, Lamb waves and Rayleigh waves, etc.) in tissues are related to the density, geometric size and mechanical properties of the tissues. Assuming that the density of the tissue is known and the geometry is measurable, an analytical expression between the propagation characteristics of the strain wave and the mechanical parameters of the tissue can be obtained. The basic principle of ultrasonic elastography based on strain wave is to stimulate the tissue to generate a strain wave by transmitting acoustic radiation force of the ultrasound system, and to record the tissue vibration by ultrasonic technology, and then measure the propagation characteristics of the strain wave. Based on the measured strain wave group velocity, phase velocity, or attenuation coefficient, solve the inverse problem to estimate the mechanical parameters of the tissue (such as elastic modulus, viscosity coefficient, etc.), and quantitatively evaluate various mechanical characteristics of the tissue.

Tracking the tissue vibration process in ultrasonic shear wave elastography is an essential step in calculating strain waves. Most techniques use ultrasound probes to focus and produce acoustic radiation forces that act on the tissue, causing it to vibrate and propagate. Immediately afterwards, the same ultrasound probe is controlled to emit a high-frame-rate plane wave and acquire an echo signal. The received echo signal is demodulated to obtain the vibration displacement curve of a series of points around the vibration source, and the propagation characteristics of the strain wave are calculated. In this process, the time resolution of the obtained vibration displacement curve depends on the frame frequency of the plane wave emission. If the frame frequency of the plane wave emission is n fps, the sampling frequency of the vibration displacement curve is n Hz, and the time resolution is 1 / n seconds.

Plane-wave ultrasound imaging is accompanied by the research of ultra-high-speed ultrasound imaging technology. Compared with the traditional ultrasound Doppler imaging system, the plane-wave blood flow imaging technology does not need to focus, and the entire image can be obtained with one parallel transmission, which greatly improves The frame rate of the image. Up to now, there are mainly two methods of single-angle and multi-angle composite imaging of plane wave imaging technology.

Single-angle plane wave emission imaging refers to the one-time transmission of the sound beam perpendicular to the transducer surface and the realization of one-time echo reception. The received signal is called a radio frequency (RF) signal. The reception of the echo signal is opposite to the transmission direction That is, the reflection from the tissue to the surface of the array element causes the array element to vibrate and generate electrical signals. The analog signal is converted into a digital signal by an analog-digital conversion module and received and stored by the ultrasound system. Tune, envelope extraction and other operations to reconstruct the tissue image. The multi-angle plane wave composite imaging algorithm obtains multiple ultrasound imaging images of the same imaging target from multiple angles by changing the transmitting angle of the transducer, and superimposes the multiple images to obtain a composite image. Plane wave multi-angle composite imaging can improve imaging quality, but reduces the imaging frame rate, which is suitable for applications where the frame rate is not high.

Single-angle plane wave imaging is often used in measurements that require high frame rates. Its frame interval T _b depends on the sound velocity of the longitudinal wave and the depth of detection, that is: T _b = 2R / c, where c is the speed of sound and R is the depth of detection. Frame rate refers to the number of frames that the imaging system can image per second, which is the reciprocal of the interval between frames. For example, it is known that the sound velocity in a tissue is about 1540m / s. If the target is detected at a depth of 2cm, the minimum interframe interval for plane wave emission calculated is ΔT = 25μs. In other words, the limit frame rate of the plane wave is 40Kfps. Assume that the distance between the array elements of the ultrasound probe is 0.3mm, that is, the distance between the two nearest points on the propagation path of the strain wave is 0.3mm. If the time of the strain wave passing through these two points has a recognizable time delay, ideally, this The peaks of the strain waves at two points differ by at least one minimum inter-frame interval. According to V _g = 0.3 mm / 25 μs = 12 m / s, the maximum shear wave velocity V _g that can be measured at this setting is about 12 m / s.

In fact, affected by factors such as the lateral resolution of the ultrasonic sound beam, it is often inaccurate when the propagation velocity of the strain wave is greater than 10 m / s. On the other hand, if the position of the detection target point is deeper and the time required for the plane wave to travel back and forth is longer, the limit frame rate will be greatly reduced, and the maximum speed of the resolvable strain wave will be greatly reduced. In the current research reports, there are few reports on the detection of strain waves with propagation speeds greater than 10 m / s.

In fact, the stiffness of tissues, such as dense sclera, certain tumors, and sclerosing blood vessels, also spreads the strain wave faster, sometimes exceeding 10 m / s. For this kind of hard and soft tissue, the frame rate of the existing single-angle plane wave ultrafast imaging is not enough to obtain the information needed to accurately calculate the wave velocity.

Summary of the invention

The technical problem mainly solved by the invention is that the frame rate of the existing single-angle plane wave ultrafast imaging is not enough to obtain the information required for accurate calculation of the wave velocity, and a new detection method and equipment are needed to improve the measurement of the strain wave propagation. The time resolution is helpful for the accurate detection of mechanical characteristic parameters such as strain wave velocity of biological soft tissues with large hardness.

According to a first aspect, an embodiment provides a method for measuring a mechanical property parameter of a tissue, including a data acquisition step including: controlling an ultrasonic probe to transmit an ultrasonic wave to a region of interest of a target tissue, and receiving an echo of the ultrasonic wave to obtain a first One echo data; after the first echo data is obtained, the ultrasound probe is controlled to emit a focused sound beam to the region of interest of the target tissue, and an acoustic radiation force is generated to excite the tissue to vibrate and generate a strain wave; the ultrasound probe emits a focused sound beam Do not transmit and / or receive ultrasonic signals to the target tissue for a period of rest time; after the rest time is over, control the ultrasound probe to transmit ultrasonic waves to the area of interest of the target tissue again to detect and receive the strain wave passing through the target tissue. The echo of the ultrasonic wave is used to obtain the second echo data; the data collection step is performed multiple times in succession to obtain multiple sets of the first echo data and the second echo data; the data processing step is based on the multiple sets of the first echo data and A plurality of data in the second echo data is used to calculate the mechanical characteristic parameters of the region of interest.

According to a second aspect, an embodiment provides an apparatus for measuring a mechanical property parameter of a tissue, including: an ultrasound probe for transmitting an ultrasonic wave to a region of interest of a target tissue and receiving an echo of the ultrasonic wave; a transmission control module for: The data acquisition includes: controlling the ultrasound probe to transmit ultrasound to a region of interest of the target tissue, and receiving the echo of the ultrasound to obtain the first echo data; after obtaining the first echo data, controlling the ultrasound probe to the region of interest of the target tissue The focused acoustic beam is emitted to generate acoustic radiation to stimulate the tissue to vibrate and generate the propagation of strain waves; the ultrasonic probe does not transmit and / or receive ultrasonic signals to the target tissue during a resting time after the focused acoustic beam is emitted; after the resting time is over , Controlling the ultrasonic probe to transmit ultrasonic waves to the region of interest of the target tissue again to detect the strain wave passing through the target tissue, and receive the echo of the ultrasonic wave to obtain the second echo data; perform the data collection step multiple times in succession to obtain Multiple sets of first echo data and second echo data; data processing module, A first plurality of sets of data to the plurality of echo data and echo data in the second mechanical characteristic parameter is calculated based on the region of interest.

According to the method and equipment for measuring tissue mechanical characteristic parameters according to the above embodiments, through multiple excitation fusion detection methods, the time resolution for measuring the propagation of strain waves can reach several times that of the single excitation detection method of the original technology, which is helpful Realize accurate detection of strain wave velocity of biological soft tissues with high hardness.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a device for measuring mechanical characteristics of tissues;

FIG. 2 is a flowchart of a data acquisition step process for detecting biological tissue multiple times in an embodiment; FIG.

3 is a displacement curve of each array element obtained based on demodulation of multiple sets of first echo data and second echo data in an embodiment;

4 is a displacement curve obtained by fusing multiple sets of first echo data and second echo data in an embodiment;

FIG. 5 is a strain wave group velocity obtained by fitting a plurality of sets of first echo data and second echo data according to an embodiment.

detailed description

The present invention will be further described in detail below through specific embodiments in combination with the accompanying drawings. In the different embodiments, similar elements are labeled with associated similar elements. In the following embodiments, many details are described so that the present application can be better understood. However, those skilled in the art can effortlessly realize that some of these features can be omitted in different situations, or can be replaced by other elements, materials, and methods. In some cases, some operations related to this application are not shown or described in the description. This is to avoid that the core part of this application is overwhelmed by too much description. For those skilled in the art, these are described in detail. The related operations are not necessary, they can fully understand the related operations according to the description in the description and the general technical knowledge in the field.

In addition, the features, operations, or features described in the specification may be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be sequentially swapped or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the description and drawings are only for clearly describing a certain embodiment, and are not meant to be a necessary order, unless otherwise stated that a certain order must be followed.

The serial numbers of components in this document, such as "first", "second", etc., are only used to distinguish the described objects and do not have any order or technical meaning. The terms “connection” and “connection” in this application include direct and indirect connections (connections) unless otherwise specified.

Please refer to FIG. 1. The structure of a device 100 for measuring mechanical parameters of a tissue is shown in FIG. 1, and includes an ultrasound probe 101, a transmission control module 102, a data processing module 105, a display module 106 and a memory 107. In a specific embodiment, a device 100 for measuring mechanical properties of a tissue further includes a transmitting and receiving module 103 and an echo processing module 104. The transmitting control module 102 is signal-connected to the ultrasonic probe 101 through the transmitting and receiving module 103. The ultrasonic probe 101 is signal-connected to the echo processing module 104 through the transmitting and receiving module 103, the output of the echo processing module 104 is connected to the data processing module 105, and the output of the data processing module 105 is connected to the display module 106. The memory 107 is connected to the data processing module 105.

The ultrasound probe 101 includes multiple transducers. The transducers are also called array elements, and are used to realize the mutual conversion of electrical pulse signals and ultrasonic waves, so as to achieve the detection of biological tissues (such as biological tissues in human or animal bodies) 108. Transmits ultrasound waves and receives ultrasound echoes reflected back from the tissue. Multiple transducers can be arranged in a row to form a linear array, or arranged in a two-dimensional matrix to form an area array, and multiple transducers can also form a convex array. The transducer can transmit ultrasonic waves according to the excited electrical signals, or transform the received ultrasonic waves into electrical signals. Therefore, each transducer can be used to transmit ultrasonic waves to biological tissues in the region of interest, and can also be used to receive ultrasonic echoes returned by the tissue. When performing ultrasound detection, it is possible to control which transducers are used to transmit ultrasound waves, which transducers are used to receive ultrasound waves, or to control the transducers to be used to transmit ultrasound waves or receive ultrasound echoes by transmitting and receiving sequences. All transducers participating in ultrasonic emission can be simultaneously excited by electrical signals, thereby transmitting ultrasonic waves simultaneously; or the transducers participating in ultrasonic emission can also be excited by several electrical signals with a certain time interval, thereby continuously transmitting ultrasonic waves with a certain time interval .

The transmission control module 102 is used to generate a transmission sequence and output the transmission sequence to an ultrasound probe. The transmission sequence is used to control part or all of multiple array elements to transmit ultrasonic waves to biological tissue in a region of interest. The transmission sequence also provides transmission parameters (for example, The amplitude, frequency, number of waves, wave angle, wave shape and / or focus position of the ultrasonic wave, etc.). According to different purposes, the wave pattern, transmission direction and focus position of the transmitted ultrasound can be controlled by adjusting the transmission parameters. The wave pattern of the ultrasound can be pulsed ultrasound, plane wave, etc.

The transmitting and receiving module 103 is connected between the ultrasonic probe and the transmitting sequence control module 102 and the echo processing module 104, and is used for transmitting the transmitting sequence of the transmitting sequence control module 102 to the ultrasonic probe 101 and transmitting the ultrasound received by the ultrasonic probe 101. The echo signal is transmitted to the echo processing module 104.

The echo processing module 104 is configured to process an ultrasonic echo signal, for example, perform processing such as filtering, amplification, and beam combining on the ultrasonic echo signal to obtain ultrasonic echo data. In a specific embodiment, the echo processing module 104 may output the ultrasonic echo data to the data processing module 105, or may store the ultrasonic echo data in the memory 107 first. When the operation is based on the ultrasonic echo data, the data The processing module 105 reads the ultrasonic echo data from the memory 107.

The memory 107 is used to store data and programs, and the programs may include a system program of an ultrasound device, various application programs, or algorithms that implement various specific functions.

The data processing module 105 is used to obtain ultrasonic echo data, and obtain relevant parameters or images by using related algorithms.

The data processing module 105 may generate an ultrasonic image according to the ultrasonic echo data, or obtain mechanical characteristic data according to the ultrasonic echo data, and generate an image having mechanical characteristic parameters.

The display module 106 is used to display the detection result, such as an ultrasound image, a calculation result, a graphic chart, or a text description.

In order to generate a strain wave in the tissue, in one embodiment, the ultrasound probe 101 further includes a vibrator, and the vibrator may be disposed in the casing of the probe or may be disposed outside the casing. The vibrator vibrates according to a predetermined frequency, and the tissue on the traction surface vibrates with it, and uses the adhesion between the tissues to generate a strain wave propagating deep into the tissue. In another embodiment, the ultrasound probe 101 promotes tissue movement by transmitting ultrasound waves, and uses adhesion between the tissues to generate strain waves that propagate within the tissue.

However, no matter which method is used to generate the strain wave, when detecting the strain wave, the ultrasonic probe is required to continuously emit ultrasonic waves for a period of time and receive echoes of the ultrasonic waves.

In the embodiment of the present invention, a method of detecting strain wave vibration with high time resolution and wave velocity measurement based on multiple excitations is used in ultrasonic elasticity detection to detect strain wave vibration of hard biological soft tissue, and The mechanical characteristic parameters are accurately measured.

In the embodiment of the present invention, when the ultrasonic device 100 is used for detecting the mechanical parameters of the tissue, the ultrasonic probe 101 includes various probes that can perform ultrasonic B-type imaging, such as a linear array probe, a convex array probe, a phased array probe, Volume probes and instantaneous elastic probes. The user stably contacts the ultrasound probe 101 with the surface of the biological body 108, and sets the ultrasound transmission parameters through the emission control module 102, such as setting the emission frequency, focus intensity, focus position, scanning range, scanning time, and the like.

The transmitting and receiving module 103 is used to switch between transmitting and receiving. When the ultrasonic wave needs to be transmitted, the transmitting and receiving module 103 is switched to a state in which the transmitting control module 102 and the ultrasonic probe 101 are electrically connected, so that the transmitting control module 102 transmits ultrasonic waves. The transmission parameters are transmitted to the ultrasonic probe 101, and the ultrasonic probe 101 generates corresponding ultrasonic waves under electrical excitation. When it is necessary to receive the ultrasonic echo, the transmitting and receiving module 103 switches to the state where the ultrasonic probe 101 and the echo processing module 104 are electrically connected, so that the ultrasonic probe 101 converts the induced ultrasonic echo signal into an electrical signal and transmits it to the echo. Wave processing module 104.

Example 1:

This embodiment includes:

Step 10, data collection steps, please refer to Figure 2, including:

First, the ultrasound probe is controlled to transmit ultrasound to a region of interest of the target tissue, and receive echoes of the ultrasound to obtain first echo data, where the first echo data includes multiple frames of echo data;

Secondly, after the first echo data is obtained, the ultrasound probe is controlled to emit a focused sound beam to the region of interest of the target tissue, generating acoustic radiation forces to stimulate the tissue to vibrate, and the propagation of strain waves is generated; During the rest period, stay still, that is, do not transmit and / or receive ultrasonic signals to the target tissue;

Then, after the resting time is over, the ultrasonic probe is controlled to transmit ultrasonic waves to the region of interest of the target tissue again to detect the strain wave passing through the target tissue, and receive the echo of the ultrasonic wave to obtain the second echo data; the second echo The data includes multiple frames of echo data;

The data acquisition step is performed multiple times in succession to obtain multiple sets of first echo data and second echo data; in this process, the resting time in each data acquisition step is the same as the previous resting time Time delay Δt, as shown in Figure 2, when the first resting time in the first data collection step is t, the second resting time in the second data collection step is t + Δt, and the third data collection step The third resting time of the step is t + 2Δt, and so on. When K data acquisition steps are performed continuously, the delay Δt between the resting times = the ultrasonic frame interval T / K detected by the second echo data.

Step 20: data processing steps. Specifically, it refers to calculating the mechanical characteristic parameters of the region of interest based on a plurality of sets of the first echo data and the second echo data. Including: demodulating the original ultrasonic echo data of the first echo data and the second echo data of each group, and then fusing the demodulated data of multiple groups to obtain the vibration displacement curve of the tissue. The mechanical properties of the tissue can be calculated.

Example 2:

Please refer to FIG. 1 and FIG. 2. In this embodiment, a device 100 for measuring mechanical properties of tissues is adopted. Among them, the ultrasonic probe 101 is a 128-element linear array probe, and the excitation maximum voltage is 70V and the excitation center frequency. It is 6.25MHz, and the frame rate of data acquisition is 20K fps. The acoustic radiation force is focused using 35 transducers, the maximum excitation voltage is 58V, and the center frequency of the excitation is 4MHz. The specific process of using the detection device 100 to measure tissue mechanical characteristics parameters is as follows:

The transmission control module 102 controls the ultrasonic probe 101 to transmit ultrasonic waves to the region of interest of the target tissue 108 in the plane wave imaging mode through the transmission and reception module 103, and the echo processing module 104 receives the target tissue in static state at a frame rate of 20 KHz through the transmission and reception module 103. Frame echo signals to obtain first echo data. In this embodiment, the first echo data is composed of 10 frames of plane wave imaging data.

After obtaining the first echo data, the transmission control module 102 controls the 35 array elements to focus through the transmission and reception module 103 to generate acoustic radiation forces to stimulate the region of interest of the target tissue to vibrate, and a strain wave propagates in the direction of the vibration, and the target tissue begins After the vibration, the transmission control module 102 controls the transmission and reception module 103 to suspend the external excitation of the region of interest, and the data detection operation enters a resting time. In this embodiment, the resting time is set to 200 μs.

As shown in FIG. 2, after the resting time is over, the transmission control module 102 controls the ultrasonic probe 101 to transmit ultrasonic waves to the target region of the target tissue 108 in the plane wave imaging mode through the transmitting and receiving module 103 to perform the strain wave passing through the target tissue. It is detected that the echo processing module 104 receives the 40-frame echo signal to the target tissue under static state through the transmitting and receiving module 103 at a frame rate of 20 KHz, and obtains the second echo data. In this embodiment, the second echo data is composed of 40 Composition of frame plane wave imaging data.

As shown in FIG. 2, the measurement device 100 performs the above-mentioned data acquisition operation continuously five times, and completes data acquisition of five sets of first echo data and second echo data. Among them, the resting time in each data collection step has the same time delay Δt from the last resting time. When K data acquisition steps are performed continuously, the delay Δt between the resting times = the ultrasonic frame interval T / K of the second echo data detection. In this embodiment, a total of 5 consecutive data acquisition operations, and the interval between plane wave detections is 50 μs, then each resting delay time Δt = 50/5 = 10 μs, it can be obtained that the first The resting time is 200 μs, the second resting time is 210 μs, the third resting time is 220 μs, the fourth resting time is 230 μs, and the fifth resting time is 240 μs.

After the detection is completed, the data processing module 105 demodulates the results of the first acquisition data and the second acquisition data obtained in each data acquisition operation, and then takes out the data of the area of interest and performs data smoothing and noise removal processing to obtain multi-channel tissue vibration. The displacement information is used to obtain the tissue displacement curve under each array element. The sampling time interval is 50 μs, as shown in Figure 3. The results of the five detections are then fused, that is, the first one of the five data acquisition operations is taken out in sequence. The data is the first 5 data, and then the second data from the five data collection operations is arranged in sequence ..... The last data from the five data collection operations is the last five data of the synthesized data, so all The data is fused together, and the obtained displacement curve is shown in Figure 4. The sampling interval is 10 μs, that is, the vibration displacement curve with a sampling rate equivalent to 5 times the original sampling rate is obtained, that is, 5 times the original sampling rate is obtained. Detection time resolution of the sampling rate; through calculation of the detection results, the deformation process of the tissue vibration can be accurately obtained, and the strain wave can be calculated Propagation velocity, as shown in FIG. The strain wave velocity can be used to quantitatively estimate the mechanical characteristics of biological tissues. This method can solve the problem of insufficient frame frequency of the existing single-plane wave detection technology, and realize the measurement of deeper tissue detection points.

The above uses specific examples to illustrate the present invention, but is only used to help understand the present invention, and is not intended to limit the present invention. For those of ordinary skill in the art, according to the idea of the present invention, changes can be made to the above specific implementations.

Claims

A method for measuring parameters of tissue mechanical characteristics, comprising:

The data acquisition step includes: controlling the ultrasound probe to transmit ultrasound to a region of interest of the target tissue, and receiving echoes of the ultrasound to obtain first echo data; and after obtaining the first echo data, controlling the ultrasound probe to the region of interest of the target tissue The focused acoustic beam is emitted to generate acoustic radiation to stimulate the tissue to vibrate and generate the propagation of strain waves; the ultrasonic probe does not transmit and / or receive ultrasonic signals to the target tissue during a resting time after the focused acoustic beam is emitted; after the resting time is over , Controlling the ultrasonic probe to transmit ultrasonic waves to the region of interest of the target tissue again to detect the strain wave passing through the target tissue, and receive the echo of the ultrasonic wave to obtain the second echo data;

Performing the data collection step multiple times in succession to obtain multiple sets of first echo data and second echo data;

The data processing step calculates a mechanical characteristic parameter of the region of interest based on a plurality of sets of the first echo data and the second echo data.
The method according to claim 1, characterized in that during the continuous data acquisition step, the resting time of each time is longer than the previous resting time by Δt; when K data acquisition steps are continuously performed , Δt = ultrasonic frame interval T / K detected by the second echo data.
The method according to claim 1, wherein the first echo data and the second echo data include multiple frames of echo signals, respectively.
The method according to claim 1, wherein calculating the mechanical characteristic parameter of the region of interest based on a plurality of sets of the first echo data and the second echo data comprises: for each group of first The echo data and the original ultrasonic echo data of the second echo data are demodulated, and then multiple sets of demodulated data are fused to calculate the mechanical characteristic parameters of the tissue.
The method according to claim 4, characterized in that performing fusion processing on a plurality of groups of demodulated data to calculate a mechanical characteristic parameter of the tissue comprises: fusing the plurality of groups of demodulated data to obtain a displacement curve of the tissue, The mechanical characteristic parameters of the tissue are calculated from the displacement curve of the tissue.
A device for measuring parameters of tissue mechanical characteristics, comprising:

An ultrasound probe for transmitting ultrasound waves to a region of interest of a target tissue and receiving echoes of the ultrasound waves;

The transmission control module is used for data acquisition, including: controlling the ultrasonic probe to transmit ultrasonic waves to the region of interest of the target tissue, and receiving the echo of the ultrasonic wave to obtain the first echo data; after obtaining the first echo data, controlling the ultrasonic probe pair The focused tissue of the target tissue emits a focused acoustic beam, which generates acoustic radiation to stimulate the tissue to vibrate and generate the propagation of strain waves. The ultrasound probe does not transmit and / or receive ultrasonic signals to the target tissue during a rest period after the focused acoustic beam is emitted. ; After the resting time, control the ultrasound probe to transmit ultrasound again to the region of interest of the target tissue to detect the strain wave passing through the target tissue and receive the echo of the ultrasonic wave to obtain the second echo data;

Performing the data collection step multiple times in succession to obtain multiple sets of first echo data and second echo data;

The data processing module is configured to calculate the mechanical characteristic parameters of the region of interest based on a plurality of sets of the first echo data and the second echo data.
The device according to claim 6, further comprising: during the continuous data collection step, each resting time is longer than the previous resting time by Δt; when K consecutive data collection steps are performed At time, Δt = the ultrasonic frame interval T / K detected by the second echo data.
The device according to claim 6, wherein the first echo data and the second echo data each include a multi-frame echo signal.
The device according to claim 6, comprising: calculating the mechanical characteristic parameters of the region of interest based on a plurality of sets of the first echo data and the second echo data, comprising: a data processing module pair Each group of the first echo data and the second echo data are subjected to demodulation of the original echo data, and then multiple demodulated data are fused to calculate the mechanical characteristics of the tissue.
The device according to claim 9, further comprising: performing fusion processing on a plurality of groups of demodulated data to calculate a mechanical characteristic parameter of the tissue, comprising: fusing the plurality of groups of demodulated data to obtain a displacement curve of the tissue. From the displacement curve of the tissue, calculate the mechanical properties of the tissue.