CN106618635B - Shear wave elastography method and device - Google Patents

Abstract

The present invention relates to a shear wave elastography method and device, the method comprising: acquiring sampling data of an object to be detected, the sampling data including ultrasonic image data in a Cartesian coordinate system; Coordinate conversion is performed to convert the ultrasonic image data of the rectangular coordinate system into ultrasonic image data of the polar coordinate system; the ultrasonic image data of the polar coordinate system is processed by a preset processing method to obtain the Shear wave elastography of the elastic modulus of the object to be detected; visualizing the shear wave elastography to display the elastic modulus of the object to be detected. The shear wave elastography of the object to be detected is realized based on coordinate transformation, and the shear wave of the long-axis section and the shear wave of the short-axis section of the object to be detected can be processed to obtain accurate elastic quantification of the object to be detected and improve the treatment The pathology detection accuracy of the detected object.

Description

Shear wave elastography method and device

technical field

The present invention relates to the field of ultrasonic medical technology, and more particularly to a shear wave elastography method and device.

Background technique

Ultrasound imaging is widely used in clinical diagnosis due to its real-time, cheap, non-invasive and non-ionizing radiation advantages. Ultrasound elastography, especially shear wave imaging based on acoustic radiation force, plays a huge role in the qualitative and quantitative measurement of tissue elasticity, for example, vascular shear wave elastography is crucial for the quantification of vessel wall elasticity effect. However, due to some characteristics of some tissues, the shear wave elastography in the related art cannot accurately characterize and quantify the elasticity. Taking blood vessels as an example, blood vessels have anisotropic properties, so that when the blood vessels are sheared During wave elastography, it is necessary to consider both the shear wave of the long-axis section and the shear wave of the short-axis section of the blood vessel. The shear wave elastography in the related art can only perform shear wave elastography on the long-axis section of the blood vessel. It will cause inaccurate quantification of blood vessel elasticity and reduce the accuracy of pathological detection of blood vessels.

Therefore, it is necessary to provide a shear wave elastography method and device to at least partly solve the above problems.

Contents of the invention

In view of the above problems, a shear wave elastography method and device of the present invention is proposed, which can obtain more accurate elastic quantification for the object to be detected, such as body tissue, blood vessel, etc., and improve the pathological detection accuracy of the object to be detected.

According to one aspect of the present invention, a shear wave elastography method is provided, the method comprising:

Acquiring sampling data of the object to be detected, the sampling data including ultrasonic image data in a rectangular coordinate system; performing coordinate conversion on the ultrasonic image data in the rectangular coordinate system to convert the ultrasonic image data in the rectangular coordinate system into polar coordinates Ultrasonic image data of the polar coordinate system; the ultrasonic image data of the polar coordinate system is processed by a preset processing method to obtain shear wave elastography used to characterize the elastic modulus of the object to be detected; the shear wave elastography Wave elastography performs visualization processing to display the elastic modulus of the object to be detected.

Optionally, performing coordinate transformation on the ultrasonic image data in the rectangular coordinate system includes: performing spatial interpolation on the ultrasonic image data in the rectangular coordinate system to obtain ultrasonic image data in the polar coordinate system.

Optionally, the spatial interpolation of the ultrasonic image data in the Cartesian coordinate system includes: determining the geometric center of the object to be detected; Perform data sampling in the angular direction and radial direction of the coordinate system to obtain sampling data points; use the ultrasonic image data in the rectangular coordinate system to perform spatial interpolation on the adopted data points to obtain ultrasonic image data in the polar coordinate system.

Optionally, the processing the ultrasonic image data of the polar coordinate system by a preset processing method includes: processing the ultrasonic image data of the polar coordinate system by a first processing method to obtain the ultrasonic image data of the polar coordinate system The displacement of any data point of the image data and the shear wave propagating along the direction of interest of the object to be detected; and, based on the displacement of any data point, a second processing method is used to The circumferentially propagating shear wave is processed to obtain the shear wave dispersion curve.

Optionally, the processing of the ultrasonic image data in the polar coordinate system by using a preset processing method further includes: obtaining a The velocity of the shear wave.

Optionally, the processing the ultrasonic image data in the polar coordinate system by the first processing method includes: performing speckle tracking on the ultrasonic image data in the polar coordinate system to obtain any data point in the polar coordinate system Radial displacement and circumferential displacement in; And establish displacement time curve based on described radial displacement and circumferential displacement; Carry out two-dimensional Fourier transform to described displacement time curve, to obtain Fourier transform result, wherein, The different angle ranges of the Fourier transform results represent motion information in different directions of the shear wave; windowing is performed on the angle of interest, and then undergoes inverse Fourier transform to obtain the sensory information along the object to be detected. Shear waves propagating in the direction of interest.

Optionally, performing speckle tracking on the ultrasonic image data in the polar coordinate system includes: performing windowing processing on any data point in the ultrasonic image data in the polar coordinate system to obtain a data window corresponding to the data point ; When the correlation of the data window in the two consecutive frames of ultrasonic image data before and after is the largest, determine the radial displacement and the circumferential displacement of the data point in the polar coordinate system.

Optionally, the said displacement based on any one of the data points, and using the second processing method to process the shear wave propagating circumferentially along the object to be detected comprises: based on the displacement of any one of the data points, Obtaining the displacement-time curves obtained by the shear wave front arriving at the position at different times; performing a two-dimensional Fourier transform on the displacement-time curves to obtain a Fourier transform result, which includes Frequency values and all wave values corresponding to any frequency value; for an angle of interest, a shear wave dispersion curve is established based on the maximum wave value corresponding to each of the frequency values in the angle of interest.

Optionally, the performing visualization processing on the shear wave elastography includes: performing spatial interpolation on the shear wave elastography in the polar coordinate system, so as to obtain the visualization data of the shear wave elastography.

According to another aspect of the present invention, a shear wave elastography device is provided, and the device includes: a data acquisition unit for acquiring sampling data of an object to be detected, the sampling data including ultrasonic image data in a Cartesian coordinate system; coordinate conversion A unit for performing coordinate transformation on the ultrasonic image data of the rectangular coordinate system, so as to convert the ultrasonic image data of the rectangular coordinate system into ultrasonic image data of the polar coordinate system; a processing unit for processing the ultrasonic image data by a preset processing method The ultrasonic image data in the polar coordinate system is processed to obtain shear wave elastography for characterizing the elastic modulus of the object to be detected; a visualization unit is used for visualizing the shear wave elastography, used to display the elastic modulus of the object to be detected.

The shear wave elastography method and device provided by the embodiments of the present invention realize the shear wave elastography of the object to be detected based on coordinate transformation (transformation from a rectangular coordinate system to a polar coordinate system), and can shear the long axis section of the object to be detected. The wave and the shear wave of the short-axis section are processed to obtain accurate elastic quantification of the object to be detected, and to improve the pathological detection accuracy of the object to be detected.

Description of drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing the embodiments of the present invention in more detail with reference to the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification, and are used together with the embodiments of the present invention to explain the present invention, and do not constitute limitations to the present invention. In the drawings, the same reference numerals generally represent the same components or steps.

FIG. 1 shows a schematic flow diagram of a shear wave elastography method according to an embodiment of the present invention;

Fig. 2 shows a schematic diagram of a spatial interpolation implementation process according to an embodiment of the present invention;

Fig. 3 shows a schematic diagram of the principle of speckle tracking according to an embodiment of the present invention;

Fig. 4 shows a structural block diagram of a shear wave elastography device according to an embodiment of the present invention.

Detailed ways

In order to make the objects, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Apparently, the described embodiments are only some embodiments of the present invention, rather than all embodiments of the present invention, and it should be understood that the present invention is not limited by the exemplary embodiments described here. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without creative effort shall fall within the protection scope of the present invention.

Acoustic radiation force-based shear wave elastography is an ultrasound elastography technique for assessing tissue stiffness. The basic principle is: the probe emits high-energy ultrasonic waves to the soft tissue of the living body to generate an acoustic radiation force. Under the action of the acoustic radiation force and the shear stress of the tissue, the soft tissue in a specific area will generate vibrations that propagate around. Thus, shear waves are generated. Since there is a correlation between the hardness of the soft tissue of the organism and the velocity of the shear wave, the hardness of the soft tissue of the organism can be analyzed by detecting the velocity of the shear wave.

The shear wave elastography of the related art may include two key points: 1. Consider the axial displacement, that is, the vibration direction of the shear wave; 2. Only consider a certain direction of interest when setting the direction filter. For soft tissues such as blood vessels, the shear wave elastography in the related art can only process the shear wave imaging of the long axis section, but not the shear wave elastography of the short axis section. However, for shear wave elastography in the short-axis view of vessels, radial displacement rather than axial displacement needs to be considered, and a directional filter along the circumferential filter is required. Therefore, it is difficult to accurately quantify the elasticity of blood vessels through the shear wave elastography of the related art, which reduces the accuracy of pathological detection of blood vessels.

In order to solve the above-mentioned problems, the embodiment of the present invention proposes a shear wave elastography method and device, which realizes shear wave elastography of the object to be detected based on coordinate transformation, obtains accurate elastic quantification of the object to be detected, and improves Pathological detection accuracy of the object to be detected.

The shear wave elastography method and device provided by the present invention will be described in detail below with reference to the accompanying drawings, so that those skilled in the art can clearly and accurately understand the technical solution of the present invention.

Fig. 1 shows a schematic flowchart of a shear wave elastography method according to an embodiment of the present invention. As shown in Figure 1, a shear wave elastography method provided by an embodiment of the present invention includes the following steps:

Step 110, acquiring sampling data of the object to be detected, wherein the sampling data includes ultrasonic image data in a Cartesian coordinate system.

In this step, the region of interest of the object to be detected may be excited by the force of acoustic radiation, and ultra-high-speed ultrasonic imaging is performed on the region of interest to obtain ultrasonic image data of the region of interest of the object to be detected. Exemplarily, the ultrasound image data may include at least one of RF (Radio Frequency, radio frequency) data, envelope data, and B-mode data.

Taking blood vessels as an example, intravascular elastography can use balloons, blood pressure changes or external extrusion to stimulate blood vessels, estimate the movement of blood vessels, that is, displacement (generally longitudinal), obtain the strain distribution of blood vessels, and thus characterize the elasticity of blood vessels. In the embodiment of the present invention, the blood vessel can be excited by the force of acoustic radiation to obtain the ultrasonic image data of the blood vessel. Exemplarily, the ultrasonic image data obtained in this step is ultrasonic image data in a Cartesian coordinate system.

Step 120, performing coordinate transformation on the ultrasonic image data in the rectangular coordinate system, so as to convert the ultrasonic image data in the rectangular coordinate system into ultrasonic image data in the polar coordinate system.

In this step, the ultrasonic image data in the rectangular coordinate system may be converted into ultrasonic image data in the polar coordinate system through coordinate transformation. The coordinate conversion from the Cartesian coordinate system to the polar coordinate system can be realized by spatial interpolation. As an example, the geometric center of the object to be detected can be determined as the polar coordinate origin, and data sampling is performed on the angular direction and radial direction of the polar coordinate system according to the preset sampling rate to obtain sampling data points. The image data is used to perform spatial interpolation on the data points to obtain the ultrasonic image data in the polar coordinate system. Exemplarily, in the polar coordinate system, the abscissa is an angle, and the ordinate is a radius. With regard to determining the geometric center of the object to be detected, for example, it may be determined by manual selection, or the geometric center may be selected by performing automatic image segmentation on the image of the object to be detected.

Still taking the blood vessel as an example, the geometric center of the blood vessel (for example, the center of a circle) is taken as the origin of polar coordinates, and linear sampling is emitted from the origin, wherein the direction along the ray is the radial direction, and the direction perpendicular to the ray is the angular direction. In the embodiment of the present invention, both the radial direction and the angular direction of the blood vessel are sampled according to the preset sampling rate to obtain the adopted data points, and then the ultrasonic image data of the Cartesian coordinate system is used to perform spatial interpolation on the adopted data points to realize Cartesian coordinates Coordinate transformation from the polar coordinate system to obtain the ultrasonic image data in the polar coordinate system. The preset sampling rate may be, for example, the number of data points collected in any direction of the polar coordinate system, which may be set according to actual requirements, and is not limited in this embodiment of the present invention. The spatial interpolation method may be implemented by, for example, linear interpolation, polynomial fitting interpolation, etc., and the present invention is not limited thereto.

The following will refer to the schematic diagram of the implementation process of spatial interpolation in the embodiment of the present invention shown in FIG. 2 . It can be understood that the interpolation embodiment shown in FIG. 2 is only an example and does not limit the present invention. In Figure 2, two-dimensional space interpolation is taken as an example. The coordinates of any data point in the Cartesian coordinate system can be expressed as (x, y). After determining the geometric center of the object to be detected (for example, the center of the blood vessel), any A data point may be expressed as (r, θ) in polar coordinates. The solid points in the figure represent the ultrasonic image data in the Cartesian coordinate system, and the hollow points represent the data that needs to be obtained in polar coordinates after the center of the circle is determined (ultrasonic image data in the polar coordinate system), which can be obtained by uniform sampling in the radial direction and angular direction . The information of the hollow points can be obtained through spatial interpolation according to the information of the solid points.

In step 130, the ultrasonic image data in the polar coordinate system is processed by a preset processing method to obtain shear wave elastography used to characterize the elastic modulus of the object to be detected.

Shear wave elastography is a method of imaging by detecting the propagation of shear waves generated by the excitation of tissue by the force of acoustic radiation. The shear modulus of the tissue can be obtained by computing the shear wave elastography, which can be used to analyze the histopathology.

In this step, the ultrasonic image data in the polar coordinate system may be processed by a preset processing method, so as to obtain the shear wave elastography of the object to be detected. According to an embodiment of the present invention, the ultrasonic image data in the polar coordinate system can be processed by the first processing method, so as to obtain the displacement and propagation of any data point of the ultrasonic image data in the polar coordinate system along the direction of interest of the object to be detected The shear wave and the shear wave propagating along the circumferential direction of the object to be detected are processed by a second processing method based on the displacement of any data point, so as to obtain a shear wave dispersion curve.

Further, in some embodiments, the processing of the ultrasonic image data in the polar coordinate system by the first processing method may include the following steps:

Step A, performing speckle tracking on the ultrasonic image data in the polar coordinate system to obtain the radial displacement and the circumferential displacement of any data point in the polar coordinate system.

In this step, displacement estimation can be realized by speckle tracking, wherein the implementation methods of speckle tracking include all methods of block motion matching such as cross-correlation, auto-correlation, and optical flow method that can obtain two-dimensional displacement in polar coordinates.

Exemplarily, any data point in the ultrasonic image data of the polar coordinate system can be windowed to obtain the data window corresponding to the data point. When the correlation of the data window in the ultrasonic image data of two consecutive frames (evaluation correlation There are many parameters, for example, it can be the autocorrelation coefficient, or the cross-correlation coefficient, etc.) When the maximum, determine the radial displacement and circumferential displacement of the data point in the polar coordinate system. In the embodiment of the present invention, the correlation coefficient can be calculated and determined by means of autocorrelation, cross-correlation, absolute error sum, amplitude difference square sum, and optical flow method. It can be understood that the calculation of the correlation coefficient is not limited to these several implementation methods , can also be realized by other block-matching motion estimation algorithms, which will not be repeated here. The schematic diagram of the principle of speckle tracking is shown in Fig. 3 . As shown in image a of Figure 3, determine a region of interest (as shown in the data window position), since the shear wave is in continuous motion, it needs to be searched and tracked in at least two frames of images, as shown in Figure 3 For images b and c, when the correlation of the data window in two consecutive frames of ultrasound image data is the largest (it can be understood as the position with the best matching degree, that is, the best matching position in image d in Figure 3), the angles along the The displacement in the direction and radial direction, that is, the radial displacement and the circumferential displacement, are the two displacements identified in the d image in Fig. 3 .

Step B, establishing a displacement-time curve based on the radial displacement and the circumferential displacement.

Exemplarily, for example, on the propagation path of the region of interest of the object to be detected, any moment can correspond to the spatial position where the wavefront arrives, and several consecutive moments can be integrated, one dimension represents time, and the other dimension represents space Since the wavefront propagation is continuous, the situation of the wavefront propagation can be determined in two-dimensional space, that is, the displacement time curve can be established.

Step C, performing a two-dimensional Fourier transform on the displacement-time curve to obtain a Fourier transform result, wherein different angle ranges of the Fourier transform result represent motion information of shear waves in different directions.

Step D, perform windowing processing on the angle of interest, and then undergo an inverse Fourier transform to obtain a shear wave propagating along the direction of interest of the object to be detected.

Steps C and D implement direction filtering, that is, Fourier transform, inverse Fourier transform, and direction windowing are performed on the displacement-time curve to obtain shear waves propagating in the direction of interest.

In step 130, the step of processing the shear wave propagating in the circumferential direction of the object to be detected by the second processing method based on the displacement of any data point may include: based on the displacement of any data point, obtaining the shear wave front at The displacement-time curve obtained by arriving at the position at different times, two-dimensional Fourier transform is performed on the displacement-time curve to obtain the Fourier transform result, which includes the frequency value and all wave values corresponding to any frequency value, For the angle of interest, a shear wave dispersion curve is established based on the maximum wave value corresponding to each frequency value in the angle of interest.

Exemplarily, the angle direction of interest is selected, for example, when the angle direction of interest is to the right, the information in the corresponding Fourier transform is located in the first quadrant, wherein the information in the Fourier transform includes frequency information respectively And wave number information (frequency value and wave value), take the largest wave value under any frequency value to obtain the shear wave dispersion curve of the object to be detected, that is, the shear wave phase velocity curve of different frequencies. Based on the shear wave dispersion curve to evaluate the shear modulus of the object to be detected, the accuracy rate is higher, and for the object to be detected such as blood vessels, based on the selection of the angle of interest in the polar coordinate system, it can simultaneously process long Axial section and short-axis section make up for the disadvantages of related technologies and obtain more accurate elastic quantification of the object to be detected.

According to another embodiment of the present invention, further, this step may further include obtaining the transmission velocity of the shear wave based on the displacement of any data point and the shear wave propagating along the circumferential direction of the object to be detected. Exemplarily, in the polar coordinate system, the velocity of the shear wave is measured according to the arrival position of the shear wave front at different times, so as to obtain the propagation velocity of the shear wave. Applying this embodiment, the shear modulus of the object to be detected can be evaluated in combination with the propagation velocity of the shear wave and the dispersion curve of the shear wave. The two can complement each other and further improve the accuracy of the elastic quantification of the object to be detected.

Step 140, performing visualization processing on the shear wave elastography, so as to display the elastic modulus of the object to be detected.

Since the displacement estimation and direction filtering are performed in polar coordinates, after obtaining the direction-filtered shear wave propagation, the shear wave propagation data (for example, including the vibration displacement, velocity, acceleration, etc. of the scatterers) can be calculated Coordinate transformation, that is, transforming from polar coordinates to rectangular coordinates, the transformation principle and process are the same as step 120, and will not be repeated here. The visualization of shear wave propagation is realized through coordinate transformation, that is, the visualization of shear wave elastography is realized.

Applying the shear wave elastography method provided by the embodiment of the present invention, based on the coordinate transformation (rectangular coordinate system is converted into a polar coordinate system), the shear wave elastography of the object to be detected can be realized, and the shear wave elastography of the long axis section of the object to be detected can be realized. and the shear wave of the short-axis section to obtain accurate elastic quantification of the object to be detected and improve the pathological detection accuracy of the object to be detected.

In addition, through the direction filtering process, the movement of the shear wave in the radial direction of the object to be detected (for example, the blood vessel wall) can be obtained, and the reflected wave in the circumferential direction of the object to be detected (for example, along the blood vessel wall) can be effectively removed. Provides the basis for the elastic quantitative study of the detection object.

In addition, through the shear wave imaging of the cross-section of the object to be detected (such as a blood vessel), the shear wave velocity and dispersion curve of the tube wall can be further obtained, and the elasticity of the object to be detected can be quantified in combination with the shear wave propagation velocity and dispersion curve Measurement can improve measurement precision and accuracy.

The present invention also provides a shear wave elastography device applying the above shear wave elastography method. Fig. 4 shows a structural block diagram of a shear wave elastography device according to an embodiment of the present invention. As shown in FIG. 4 , the shear wave elastography device may include a data acquisition unit 410 , a coordinate conversion unit 420 , a processing unit 430 and a visualization unit 440 . Exemplarily, the data acquisition unit 410 , the coordinate conversion unit 420 , the processing unit 430 and the visualization unit 440 can all be set in a computer and realized by an operation processing unit of the computer.

The data acquiring unit 410 may be used to acquire sampled data of the object to be detected, wherein the sampled data includes ultrasonic image data in a Cartesian coordinate system.

The coordinate conversion unit 420 can be used to perform coordinate conversion on the ultrasonic image data in the rectangular coordinate system acquired by the data acquisition unit 410, so as to convert the ultrasonic image data in the super rectangular coordinate system into the ultrasonic image data in the polar coordinate system.

The processing unit 430 may be configured to process the ultrasonic image data in the polar coordinate system obtained by the coordinate conversion unit 420 through a preset processing method, so as to obtain shear wave elastography used to characterize the elastic modulus of the object to be detected.

The visualization unit 440 may be configured to perform visualization processing on the shear wave elastography obtained by the processing unit 430, so as to display the elastic modulus of the object to be detected.

By applying the shear wave elastography device provided by the embodiment of the present invention, the shear wave elastography of the object to be detected can be realized based on coordinate transformation (transformation from a rectangular coordinate system to a polar coordinate system), and the shear wave elastography of the long axis section of the object to be detected can be realized. The wave and the shear wave of the short-axis section are processed to obtain accurate elastic quantification of the object to be detected, and to improve the pathological detection accuracy of the object to be detected.

Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are illustrative only and are not intended to limit the scope of the invention thereto. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

In the several embodiments provided in this application, it should be understood that the disclosed devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods, for example, multiple units or components can be combined or integrated. to another device, or some features may be ignored, or not implemented.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.

Similarly, it should be understood that in the description of the exemplary embodiments of the invention, in order to streamline the disclosure and to facilitate an understanding of one or more of the various inventive aspects, various features of the invention are sometimes grouped together in a single embodiment, figure , or in its description. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the corresponding claims reflect, the inventive point lies in that the corresponding technical problem may be solved by using less than all features of a single disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention.

It will be appreciated by those skilled in the art that all features disclosed in this specification (including accompanying claims, abstract and drawings) and all features of any method or apparatus so disclosed may be used in any combination, except where the features are mutually exclusive. Processes or units are combined. Each feature disclosed in this specification (including accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will understand that although some embodiments described herein include some features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the invention. and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) can be used in practice to realize some or all functions of some modules in the wire suspension point positioning device according to the embodiment of the present invention. The present invention can also be implemented as an apparatus program (for example, a computer program and a computer program product) for performing a part or all of the methods described herein. Such a program for realizing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet site, or provided on a carrier signal, or provided in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of components or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct components, and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

The above is only a specific embodiment of the present invention or a description of the specific embodiment, and the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily Any changes or substitutions that come to mind should be covered within the protection scope of the present invention. The protection scope of the present invention should be based on the protection scope of the claims.

Claims (8)

1. A method of shear wave elastography, the method comprising:

acquiring sampling data of an object to be detected, wherein the sampling data comprises ultrasonic image data of a rectangular coordinate system;

performing coordinate conversion on the ultrasonic image data of the rectangular coordinate system to convert the ultrasonic image data of the rectangular coordinate system into ultrasonic image data of a polar coordinate system;

processing the ultrasonic image data of the polar coordinate system by a preset processing method to obtain shear wave elastic imaging for representing the elastic modulus of the object to be detected;

performing visual processing on the shear wave elasticity imaging to display the elasticity modulus of the object to be detected; wherein

The processing the ultrasonic image data of the polar coordinate system by a preset processing method comprises:

processing the ultrasonic image data of the polar coordinate system by a first processing method to obtain the displacement of any data point of the ultrasonic image data of the polar coordinate system and the shear wave propagating along the interested direction of the object to be detected; and

processing the shear wave which circularly propagates along the object to be detected by a second processing method based on the displacement of any data point to obtain a shear wave frequency dispersion curve;

wherein the processing the shear wave propagating along the circumferential direction of the object to be detected by the second processing method includes:

obtaining displacement time curves obtained by the arrival positions of the shear wave wavefront at different times based on the displacement of any data point;

performing two-dimensional Fourier transform on the displacement time curve to obtain a Fourier transform result, wherein the Fourier transform result comprises frequency values and all wave values corresponding to any frequency value;

and aiming at the interested angle, establishing a shear wave dispersion curve based on the maximum wave value corresponding to each frequency value in the interested angle.

2. The method of claim 1, wherein the coordinate transforming the ultrasound image data of the rectangular coordinate system comprises:

and carrying out spatial interpolation on the ultrasonic image data of the rectangular coordinate system to obtain the ultrasonic image data of the polar coordinate system.

3. The method of claim 2, wherein spatially interpolating ultrasound image data of the orthogonal coordinate system comprises:

determining the geometric center of the object to be detected; and

taking the geometric center as a polar coordinate origin, and respectively sampling data in the angle direction and the radius direction of the polar coordinate system according to a preset sampling rate to obtain sampling data points;

and performing spatial interpolation on the sampling data points by using the ultrasonic image data of the rectangular coordinate system to obtain the ultrasonic image data of the polar coordinate system.

4. The method of claim 1, wherein the processing the ultrasound image data of the polar coordinate system by a predetermined processing method further comprises:

and obtaining the transmission speed of the shear wave based on the displacement of any data point and the shear wave propagating along the circumferential direction of the object to be detected.

5. The method of claim 1, wherein the processing ultrasound image data of the polar coordinate system by the first processing method comprises:

carrying out spot tracking on the ultrasonic image data of the polar coordinate system to obtain radial displacement and annular displacement of any data point in the polar coordinate system; and

establishing a displacement time curve based on the radial displacement and the annular displacement;

performing two-dimensional Fourier transform on the displacement time curve to obtain a Fourier transform result, wherein different angle ranges of the Fourier transform result represent motion information of the shear wave in different directions;

and windowing the interested angle, and then carrying out inverse Fourier transform to obtain the shear wave propagating along the interested direction of the object to be detected.

6. The method of claim 5, wherein the speckle tracking of ultrasound image data of the polar coordinate system comprises:

windowing any data point in the ultrasonic image data of the polar coordinate system to obtain a data window corresponding to the data point;

and when the correlation coefficient of the data window in the ultrasonic image data of two continuous frames is maximum, determining the radial displacement and the annular displacement of the data point in the polar coordinate system.

7. The method according to claim 1, wherein said visualizing said shear wave elastography comprises:

and carrying out spatial interpolation on the shear wave elastography of the polar coordinate system to obtain visual data of the shear wave elastography.

8. A shear wave elastography device, the device comprising:

the data acquisition unit is used for acquiring sampling data of an object to be detected, and the sampling data comprises ultrasonic image data of a rectangular coordinate system;

the coordinate conversion unit is used for carrying out coordinate conversion on the ultrasonic image data of the rectangular coordinate system so as to convert the ultrasonic image data of the rectangular coordinate system into ultrasonic image data of a polar coordinate system;

the processing unit is used for processing the ultrasonic image data of the polar coordinate system through a preset processing method to obtain shear wave elastic imaging used for representing the elastic modulus of the object to be detected;

the visualization unit is used for performing visualization processing on the shear wave elastography so as to display the elastic modulus of the object to be detected; wherein,

the processing unit processes the ultrasonic image data of the polar coordinate system by a preset processing method in the following way:

processing the ultrasonic image data of the polar coordinate system by a first processing method to obtain the displacement of any data point of the ultrasonic image data of the polar coordinate system and the shear wave propagating along the interested direction of the object to be detected; and

processing the shear wave which circularly propagates along the object to be detected by a second processing method based on the displacement of any data point to obtain a shear wave frequency dispersion curve;

wherein the processing the shear wave propagating along the circumferential direction of the object to be detected by the second processing method includes:

obtaining displacement time curves obtained by the arrival positions of the shear wave wavefront at different times based on the displacement of any data point;

performing two-dimensional Fourier transform on the displacement time curve to obtain a Fourier transform result, wherein the Fourier transform result comprises frequency values and all wave values corresponding to any frequency value;

and aiming at the interested angle, establishing a shear wave dispersion curve based on the maximum wave value corresponding to each frequency value in the interested angle.