Viscoelastic measurement method and ultrasound imaging system

Abstract

A viscoelasticity measurement method and an ultrasonic imaging system, the method comprising: generating a shear wave propagating in a target region of a subject to be measured (S210); transmitting an ultrasonic wave tracking the shear wave to the target region, and receiving an ultrasonic echo returned by the target region to obtain ultrasonic echo data (S220); obtaining tissue motion information in the process of the shear wave propagation according to the ultrasonic echo data (S230); extracting tissue motion target information corresponding to shear waves of at least two different frequencies from the tissue motion information (S240); and outputting the tissue motion target information of the shear waves of the at least two different frequencies, the tissue motion target information being used to reflect a viscous characteristic of the target region (S250). Thus, the viscous characteristic of the tissue is reflected by the tissue motion target information of the shear waves of the at least two different frequencies.

Description

[0001] manual Technical Field

[0002] This application relates to the field of ultrasonic imaging technology, and more specifically to a viscoelasticity measurement method and an ultrasonic imaging system. Background Technology

[0003] Ultrasound elastography, which extracts information related to tissue stiffness for imaging, is relevant to the non-invasive auxiliary diagnosis of major diseases such as breast cancer and cirrhosis, and has been a research hotspot in the field of ultrasound imaging for the past two decades. After years of development, ultrasound elastography has matured and has recently been more widely applied in clinical research and auxiliary diagnosis of various parts of the human body, including the liver, breast, thyroid, muscles and bones, blood vessels, prostate, and cervix. Ultrasound elastography can qualitatively reflect the difference in hardness of a lesion relative to surrounding tissues, or quantitatively reflect the stiffness-related physical parameters of the target tissue, such as Young's modulus and shear modulus, making it widely popular among physicians.

[0004] Commonly used ultrasound elastography techniques include strain elastography, shear wave elastography, and transient elastography. Among these, shear wave elastography generates shear waves by emitting special pulses into the tissue to create acoustic radiation force. The propagation process of these shear waves is then detected and recorded using ultrasound, and the propagation velocity is calculated to obtain the elastic modulus parameter, which reflects the tissue's stiffness, thus achieving quantitative elastography. This technology has greatly expanded the clinical applications of elastography and has attracted significant research interest.

[0005] A growing body of research has shown that human tissues possess not only elasticity but also viscosity, and both elasticity and viscosity influence the propagation speed of shear waves within the tissue. However, in most current elasticity-related studies, tissues are treated as purely elastic bodies, and elastography techniques are primarily based on this assumption. Quantitative elastography, in particular, typically only calculates and displays the elastic modulus. Summary of the Invention

[0006] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. This summary section is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0007] A first aspect of this application provides a viscoelasticity measurement method, the viscoelasticity measurement method comprising:

[0008] Shear waves are generated and propagate within the target area of ​​the object being measured;

[0009] An ultrasonic wave that tracks the shear wave is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0010] Tissue motion information during the propagation of the shear wave is obtained based on the ultrasound echo data;

[0011] Extract tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information;

[0012] Output tissue motion target information corresponding to the at least two different frequencies of shear waves, wherein the tissue motion target information is used to reflect the viscous characteristics of the target region.

[0013] A second aspect of this application provides a viscoelasticity measurement method, the viscoelasticity measurement method comprising:

[0014] At least two different frequencies of shear waves are generated sequentially in the target area of ​​the object being tested;

[0015] An ultrasonic wave that tracks at least two different frequencies of shear waves is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0016] Based on the ultrasound echo data, obtain tissue motion target information corresponding to the at least two different frequencies of shear waves;

[0017] Output tissue motion target information corresponding to the at least two different frequencies of shear waves, wherein the tissue motion target information is used to reflect the viscous characteristics of the target region.

[0018] A third aspect of this application provides a viscoelasticity measurement method, the viscoelasticity measurement method comprising:

[0019] Shear waves are generated and propagate in the target area of ​​the object being measured;

[0020] An ultrasonic wave that tracks the shear wave is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0021] Based on the ultrasound echo data, tissue motion information corresponding to the shear wave is obtained;

[0022] Extract tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information;

[0023] Based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, feature parameters reflecting the viscous characteristics of the target region are generated and displayed.

[0024] A fourth aspect of this application provides a viscoelasticity measurement method, the viscoelasticity measurement method comprising:

[0025] At least two different frequencies of shear waves are generated sequentially and propagate in the target area of ​​the object being measured.

[0026] An ultrasonic wave that tracks at least two different frequencies of shear waves is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0027] Based on the ultrasound echo data, obtain tissue motion target information corresponding to the at least two different frequencies of shear waves;

[0028] Based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, feature parameters reflecting the viscous characteristics of the target region are generated and displayed.

[0029] A fifth aspect of this application provides a viscoelasticity measurement method, the viscoelasticity measurement method comprising:

[0030] A shear wave of the target frequency that propagates in the target area of ​​the object being measured;

[0031] An ultrasonic wave that tracks the frequency of the target is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0032] Based on the ultrasound echo data, tissue motion information corresponding to the shear wave at the target frequency is obtained;

[0033] Output tissue motion information corresponding to the shear wave of the target frequency, wherein the tissue motion information is used to reflect the viscous characteristics of the target region.

[0034] A sixth aspect of this application provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0035] An ultrasonic probe is used to generate shear waves that propagate within the target area of ​​the object being measured.

[0036] A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the shear wave toward the target area;

[0037] A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data.

[0038] A processor is used to execute the viscoelasticity measurement method described in the first aspect of the embodiments of this application.

[0039] A seventh aspect of this application provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0040] An ultrasonic probe is used to sequentially generate at least two different frequencies of shear waves that propagate within a target area of ​​the object being measured.

[0041] A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the at least two different frequencies of shear waves toward the target region;

[0042] A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data.

[0043] A processor is used to execute the viscoelasticity measurement method described in the second aspect of the embodiments of this application.

[0044] An eighth aspect of this application provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0045] An ultrasonic probe is used to generate shear waves that propagate within the target area of ​​the object being measured.

[0046] A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the shear wave toward the target area;

[0047] A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data.

[0048] A processor is used to execute the viscoelasticity measurement method described in the third aspect of the embodiments of this application.

[0049] A ninth aspect of this application provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0050] An ultrasonic probe is used to sequentially generate at least two different frequencies of shear waves that propagate within a target area of ​​the object being measured.

[0051] A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the at least two different frequencies of shear waves toward the target region;

[0052] A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data.

[0053] A processor for executing the viscoelasticity measurement method described in the fourth aspect of the embodiments of this application.

[0054] A tenth aspect of this application provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0055] An ultrasonic probe is used to generate a shear wave at a target frequency that propagates within the target area of ​​the object being measured.

[0056] A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the shear wave toward the target area;

[0057] A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data.

[0058] A processor for executing the viscoelasticity measurement method described in the fifth aspect of the embodiments of this application.

[0059] The viscoelasticity measurement method and ultrasound imaging system according to embodiments of this application reflect the viscous characteristics of tissue through tissue motion target information of at least two different frequencies of shear waves. Attached Figure Description

[0060] Figure 1 A schematic block diagram of an ultrasound imaging system according to an embodiment of this application is shown;

[0061] Figure 2 This is a schematic flowchart of a viscoelasticity measurement method according to an embodiment of this application;

[0062] Figure 3 This is a spectrogram of tissue motion information according to an embodiment of this application;

[0063] Figure 4 The diagram illustrates a vibration waveform of tissue motion information according to an embodiment of this application;

[0064] Figure 5A and Figure 5B An image of tissue motion according to an embodiment of this application is shown;

[0065] Figure 6A An image of tissue motion according to another embodiment of this application is shown;

[0066] Figure 6B An image of tissue motion according to yet another embodiment of this application is shown;

[0067] Figure 7 This is a schematic flowchart of a viscoelasticity measurement method according to another embodiment of this application;

[0068] Figure 8 This is a schematic flowchart of a viscoelasticity measurement method according to another embodiment of this application;

[0069] Figure 9 This is a schematic flowchart of a viscoelasticity measurement method according to another embodiment of this application;

[0070] Figure 10 This is a schematic flowchart of a viscoelasticity measurement method according to another embodiment of this application. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of this application more apparent, exemplary embodiments according to this application will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this application, and not all embodiments of this application. It should be understood that this application is not limited to the exemplary embodiments described herein. Based on the embodiments of this application described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of this application.

[0072] The following description provides numerous specific details to offer a more thorough understanding of this application. However, it will be apparent to those skilled in the art that this application can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described to avoid confusion with this application.

[0073] It should be understood that this application can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art.

[0074] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0075] To fully understand this application, detailed steps and structures will be presented in the following description to illustrate the technical solutions proposed in this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0076] To fully understand this application, a detailed structure will be presented in the following description to illustrate the technical solution proposed in this application. Optional embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.

[0077] Below, first refer to Figure 1 An ultrasound imaging system according to an embodiment of this application is described. Figure 1 A schematic structural block diagram of an ultrasound imaging system 100 according to an embodiment of this application is shown.

[0078] like Figure 1 As shown, the ultrasound imaging system 100 includes an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118. Further, the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122. The transmitting circuit 112 and the receiving circuit 114 can be connected to the ultrasound probe 110 via the transmit / receive selection switch 120.

[0079] The ultrasonic probe 110 includes multiple transducer elements. These elements can be arranged in a row to form a linear array, or in a two-dimensional matrix to form a planar array. They can also form a convex array. Each transducer element is used to emit ultrasonic waves based on an excitation electrical signal, or to convert received ultrasonic waves into electrical signals. Therefore, each transducer element can be used to achieve the mutual conversion between electrical pulse signals and ultrasonic waves, thereby enabling the emission of ultrasonic waves to the target area of ​​the object being tested, and also to receive ultrasonic wave echoes reflected back from the tissue. During ultrasonic testing, the transmission and reception sequences can be used to control which transducer elements are used to emit ultrasonic waves and which are used to receive ultrasonic waves, or to control the transducer elements to be used in time-slotted manner for emitting ultrasonic waves or receiving ultrasonic wave echoes. Transducer elements participating in ultrasonic wave emission can be simultaneously excited by electrical signals, thus emitting ultrasonic waves simultaneously; alternatively, transducer elements participating in ultrasonic beam emission can be excited by several electrical signals with a certain time interval, thus continuously emitting ultrasonic waves with a certain time interval.

[0080] During ultrasound imaging, the transmitting circuit 112 sends a delayed-focused transmission pulse to the ultrasound probe 110 via the transmit / receive selection switch 120. Excited by the transmission pulse, the ultrasound probe 110 emits an ultrasonic beam towards the tissue of the target area of ​​the object being measured. After a certain delay, it receives the ultrasonic echo reflecting back from the tissue of the target area, carrying tissue information, and converts this ultrasonic echo back into an electrical signal. The object being measured can be a human, or an animal, such as a cat, dog, or rabbit. The receiving circuit 114 receives the electrical signal converted by the ultrasound probe 110, obtains the ultrasonic echo signal, and sends these ultrasonic echo signals to the beamforming module 122. The beamforming module 122 performs focusing delay, weighting, and channel summation on the ultrasonic echo data, and then sends it to the processor 116. The processor 116 performs signal detection, signal enhancement, data conversion, and logarithmic compression on the ultrasonic echo signal to form an ultrasound image. The ultrasound image obtained by the processor 116 can be displayed on the display 118 or stored in the memory 124.

[0081] Optionally, the processor 116 can be implemented as software, hardware, firmware, or any combination thereof, and can use one or more application-specific integrated circuits (ASICs), one or more general-purpose integrated circuits, one or more microprocessors, one or more programmable logic devices, or any combination of the foregoing circuits and / or devices, or other suitable circuits or devices. Furthermore, the processor 116 can control other components in the ultrasound imaging system 100 to perform the corresponding steps of the methods in the various embodiments of this specification.

[0082] The display 118 is connected to the processor 116. The display 118 can be a touch screen, an LCD screen, etc.; or, the display 118 can be an independent display such as an LCD screen or a television, separate from the ultrasound imaging system 100; or, the display 118 can be the screen of an electronic device such as a smartphone or tablet, etc. The number of displays 118 can be one or more. For example, the display 118 may include a main screen and a touch screen, with the main screen primarily used to display ultrasound images and the touch screen primarily used for human-computer interaction.

[0083] The display 118 can display the ultrasound images obtained by the processor 116. Furthermore, while displaying the ultrasound images, the display 118 can also provide a graphical user interface for human-machine interaction. One or more controlled objects can be set on the graphical interface, allowing the user to input operation commands using a human-machine interaction device to control these controlled objects and perform corresponding control operations. For example, icons can be displayed on the graphical interface, and the human-machine interaction device can be used to operate these icons to perform specific functions, such as drawing a region of interest bounding box on the ultrasound image.

[0084] Optionally, the ultrasound imaging system 100 may also include other human-machine interface devices besides the display 118, which are connected to the processor 116. For example, the processor 116 may be connected to the human-machine interface device via an external input / output port, which may be a wireless communication module, a wired communication module, or a combination of both. The external input / output port may also be based on USB, bus protocols such as CAN, and / or wired network protocols.

[0085] The human-computer interaction device may include an input device for detecting user input information. This input information may be, for example, control commands for the timing of ultrasound transmission / reception, operational input commands for drawing points, lines, or boxes on an ultrasound image, or other types of commands. The input device may include one or a combination of several of the following: a keyboard, mouse, scroll wheel, trackball, mobile input device (e.g., a mobile device with a touchscreen, a mobile phone, etc.), a multi-function knob, etc. The human-computer interaction device may also include an output device such as a printer.

[0086] The ultrasound imaging system 100 may also include a memory 124 for storing instructions executed by the processor, storing received ultrasound echoes, storing ultrasound images, etc. The memory may be a flash memory card, solid-state memory, hard disk, etc. It may be volatile and / or non-volatile memory, removable memory and / or non-removable memory, etc.

[0087] It should be understood that Figure 1 The components included in the ultrasound imaging system 100 shown are merely illustrative and may include more or fewer components. This application is not limiting in this regard.

[0088] Below, we will refer to Figure 2 A viscoelasticity measurement method according to an embodiment of this application is described. Figure 2 This is a schematic flowchart of a viscoelasticity measurement method 200 according to an embodiment of this application.

[0089] like Figure 2 As shown, a viscoelasticity measurement method 200 according to an embodiment of this application includes the following steps:

[0090] In step S210, a shear wave is generated that propagates within the target area of ​​the object being measured;

[0091] In step S220, an ultrasonic wave that tracks the shear wave is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data.

[0092] In step S230, tissue motion information during the propagation of the shear wave is obtained based on the ultrasound echo data;

[0093] In step S240, tissue motion target information corresponding to at least two different frequencies of shear waves is extracted from the tissue motion information;

[0094] In step S250, the tissue motion target information corresponding to the at least two different frequencies of shear waves is output, wherein the tissue motion target information is used to reflect the viscous characteristics of the target region.

[0095] The viscosity of tissues causes shear wave dispersion, resulting in different propagation patterns of shear waves of different frequencies within the tissue. The viscoelasticity measurement method 200 of this application, based on elasticity measurement, adds a step to extract tissue motion target information corresponding to at least two different frequencies of shear waves related to the shear wave dispersion effect from the tissue motion information. This tissue motion target information of at least two different frequencies of shear waves reflects the viscous characteristics of the tissue.

[0096] For example, before performing step S210, an image of the tissue structure of the object under test is first acquired, and the region of interest for viscoelastic measurement is determined based on the image of the tissue structure of the object under test.

[0097] Continue to refer to Figure 1 The processor 116 controls the transmitting circuit 112 to send the delayed-focused transmission pulse to the ultrasound probe 110 via the transmit / receive selection switch 120. Excited by the transmission pulse, the ultrasound probe 110 emits an ultrasonic beam towards the tissue of the target area of ​​the object being measured. After a certain delay, it receives the ultrasonic echo reflecting back from the tissue of the target area, carrying tissue information, and converts this ultrasonic echo back into an electrical signal. The receiving circuit 114 receives the electrical signal generated by the ultrasound probe 110, obtains the ultrasonic echo signal, and sends these ultrasonic echo signals to the beamforming module 122. The beamforming module 122 performs focusing delay, weighting, and channel summation on the ultrasonic echo data, and then sends it to the processor 116. The processor 116 performs signal detection, signal enhancement, data conversion, and logarithmic compression on the ultrasonic echo signal to form a tissue structure image, such as a B-image or C-image.

[0098] Then, the location of the region of interest can be determined based on the tissue structure image. In one example, the tissue structure image can be displayed on a monitor, allowing the user to manually select the region of interest on the tissue structure image, and the location of the region of interest can be determined based on the detected user input.

[0099] In another example, the location of the region of interest (ROI) on a tissue structure image can be automatically determined based on relevant machine recognition algorithms, or the ROI can be obtained through semi-automatic detection. For example, the location of the ROI on the tissue structure image can be automatically detected first based on machine recognition algorithms, and then the user can further modify or correct it to obtain a more accurate location of the ROI.

[0100] Next, based on the region of interest selected using the above method, a pre-set pulse sequence is used to focus acoustic radiation force onto the target area of ​​the object being tested to generate shear waves. Specifically, the ultrasound probe emits special ultrasonic driving pulses towards the tissue of the region of interest of the object being tested, thereby generating shear wave propagation in the tissue based on acoustic radiation force. The length of the ultrasonic driving pulse is generally greater than 100 μs. Since the shear wave generated by the acoustic radiation force pulse itself has a small amplitude and attenuates rapidly with propagation, multiple ultrasonic driving pulses can be emitted continuously to enhance the intensity and range of the generated shear wave.

[0101] Optionally, the spectral range of the generated shear wave can be adjusted by continuously transmitting ultrasonic driving pulses multiple times and by adjusting the transmission interval of the ultrasonic driving pulses. For example, by continuously transmitting ultrasonic driving pulses multiple times at a certain time interval PRT (e.g., 5ms), the frequency of the generated shear wave will be concentrated at the frequency point of N / PRT (e.g., 200Hz, 400Hz, 600Hz, etc.), where the frequency component at 1 / PRT is the strongest, i.e., the dominant frequency of the shear wave. Therefore, different frequencies of shear waves can be generated by changing the length of PRT.

[0102] Next, a series of ultrasound waves tracking shear waves are continuously emitted into the tissue region of interest by an ultrasound probe for a period of time (e.g., tens of milliseconds), and the ultrasound echoes are received to obtain ultrasound echo data. Based on this data, tissue motion information during shear wave propagation is obtained. The tissue motion information obtained using this method includes tissue motion information from multiple shear waves of different frequencies within the range of 0–1000 Hz. The tissue motion information of each shear wave frequency component can be considered as information characterizing the tissue vibration state caused by a shear wave of that frequency. See also... Figure 3 , Figure 3The spectrum of tissue motion information over a wide frequency band is shown. This tissue motion information includes multiple shear wave components in the range of 0 to 1000 Hz, and therefore the spectrum has a high amplitude over a wide frequency band.

[0103] Specifically, the processor of the ultrasound imaging system can calculate the tissue motion information during the propagation of shear waves within the tissue based on the aforementioned ultrasound echo data. According to wave characteristics, when a shear wave passes through a certain location within the tissue, the tissue at that location will vibrate; when the shear wave propagates away from that location, the tissue at that location will return to its original state. Therefore, by comparing the ultrasound echoes obtained at different times, tissue motion information over a period of time can be obtained. This tissue motion information can include tissue displacement, tissue velocity, tissue acceleration, tissue strain, etc., or data further processed by filtering, differentiation, integration, etc., based on the aforementioned variables.

[0104] The correlation comparison can be a comparison between ultrasound echo signals obtained at adjacent different times, or a comparison between ultrasound echoes at different times and echo signals at the same reference time. The correlation comparison algorithm can include general algorithms for conventional tissue displacement detection, such as block-matching-based cross-correlation comparison algorithms, Doppler frequency shift-based calculation methods, and phase shift-based detection methods. This application does not limit the specific algorithm used to detect tissue motion information.

[0105] Optionally, by summarizing the tissue motion information caused by shear waves at different times, the vibration waveform of the tissue can be observed. Figure 4 This shows the tissue velocity-time curve at a specific location within the tissue over a period of time. Of course, the vibration waveform of the tissue can also be observed by summarizing other tissue motion information mentioned above over a period of time, such as by plotting a tissue displacement-time curve.

[0106] In step S240, at least two different frequencies of shear wave corresponding tissue motion target information are extracted from the tissue motion information. The tissue motion target information corresponding to different frequencies of shear waves extracted from the tissue motion information can be considered as tissue motion information caused by shear waves of different frequencies. By extracting the tissue motion target information corresponding to different frequencies of shear waves from the tissue motion information, only one acoustic radiation force pulse transmission is needed to obtain the tissue motion target information corresponding to different frequencies of shear waves for comparative analysis to reflect the viscous characteristics of the tissue, without the need for multiple transmissions and receptions.

[0107] In one embodiment, tissue motion target information of at least two different frequencies of shear waves can be extracted by filtering the tissue motion information. The filtering method can be performed in the time domain, frequency domain, or by various algorithms, and the algorithm can also be convolution operation, etc. Of course, the filtering process can also include a series of processing procedures before or after filtering, which are not specifically limited here.

[0108] As mentioned above, tissue motion information can be a time-domain signal describing the change of tissue motion information over time within a region of interest. Filtering of tissue motion information can be performed in the time domain, i.e., time-domain filtering of the tissue motion information.

[0109] As another implementation, tissue motion information can be transformed into a frequency domain signal, and then frequency domain filtering can be performed on the frequency domain signal. For example, the amplitudes of all frequency bands outside the desired frequency band in the frequency domain signal can be set to zero, and then the frequency domain signal after frequency domain filtering can be inversely transformed into a time domain signal. Exemplarily, the transformation of tissue motion information from the time domain to the frequency domain can be achieved by Fourier transform, and the transformation of tissue motion information from the frequency domain to the time domain can be achieved by inverse Fourier transform.

[0110] In one embodiment, tissue motion target information can be extracted based on various suitable filters, which can be software filters or hardware filters additionally set in the ultrasound imaging system.

[0111] For example, as a more precise filtering method, at least two bandpass filters of different frequencies can be used to filter the tissue motion target information corresponding to the shear waves at different frequencies. For instance, bandpass filters of 300Hz and 600Hz can be used to extract tissue motion target information centered at 300Hz and 600Hz from the 0-1000Hz wideband tissue motion information. It is understood that when using bandpass filters, two or more bandpass filters can be used to extract tissue motion target information corresponding to shear waves at multiple frequencies from the tissue motion information.

[0112] Furthermore, as a relatively simplified filtering method, low-pass and high-pass filters can be used separately to filter tissue motion information, extracting low-frequency and high-frequency components from the tissue motion information respectively, which can then be used as two different types of tissue motion target information. For example, a 500Hz high-pass filter and a low-pass filter can be used to extract low-frequency components of 0-500Hz and high-frequency components of 500-1000Hz from the 0-1000Hz wideband tissue motion information.

[0113] Furthermore, the separated tissue motion target information does not necessarily include only a single center frequency, but rather a frequency band with a preset bandwidth centered at a preset frequency point. By adjusting the filter parameters used for filtering, the bandwidth of the shear wave frequency of the extracted tissue motion target information can be changed. The more concentrated the shear wave frequency of the separated and extracted tissue motion target information, the more accurately the tissue motion target information at the current shear wave frequency can be obtained. However, correspondingly, because more tissue motion information is filtered out, the signal-to-noise ratio of the obtained signal will decrease. Therefore, by adjusting the filter parameters, the desired balance between the accuracy of the tissue motion target information and the signal-to-noise ratio of the signal can be achieved.

[0114] In some embodiments, since tissue motion information is related to the frequency of shear waves, frequency information of at least two different shear waves can also be output. For example, frequency information of at least two different shear waves can be output simultaneously with tissue motion target information of at least two different shear waves.

[0115] In step S250, the tissue motion target information corresponding to at least two different frequencies of shear waves is output. The tissue motion target information corresponding to different frequencies of shear waves is used to reflect the viscous characteristics of the tissue.

[0116] To more vividly represent the viscous state of tissue, the tissue motion target information corresponding to shear waves of different frequencies can be output graphically. Alternatively, to quantitatively represent the viscous state of tissue, the tissue motion target information corresponding to at least two different frequencies of shear waves can be output numerically.

[0117] When outputting tissue motion target information graphically, a tissue motion image can be generated based on the tissue motion target information corresponding to at least two different frequencies of shear waves, and the tissue motion image can be displayed. The following is in conjunction with... Figure 5A , Figure 5B , Figure 6A and Figure 6B Several exemplary tissue motion images are shown.

[0118] like Figure 5A and Figure 5B As shown, in one embodiment, the tissue motion image includes at least one frame, and each frame of the tissue motion image reflects tissue motion target information corresponding to a shear wave of at least one frequency at a preset time. Figure 5AThe three tissue motion images shown reflect the tissue motion target information at times t1, t2, and t3, respectively. The horizontal axis represents the width direction, and the vertical axis represents the depth direction. The curve in each tissue motion image represents the shear wave propagation state at the current time. Due to the influence of tissue viscosity, the propagation state of shear waves at different frequencies is different. Figure 5A In this example, tissue motion information is abstracted into the form of lines. However, in other examples, different colors or grayscale values ​​can be used at different locations in the image to represent tissue motion information at each location, such as the magnitude of tissue displacement or the magnitude of tissue motion velocity at each location. For example, Figure 5B The text uses different shades of gray to show the tissue motion target information at times t1, t2, and t3.

[0119] exist Figure 5A and Figure 5B In this example, each frame of tissue motion image reflects the tissue motion target information corresponding to a shear wave of a certain frequency at a preset time. Frames of target tissue motion images corresponding to shear waves of different frequencies at the same preset time are simultaneously displayed in different windows. In other examples, each frame of tissue motion image may also reflect the tissue motion target information corresponding to at least two different frequencies of shear waves at a preset time, and frames of target tissue motion images corresponding to at least two different frequencies of shear waves at different times are displayed in the same window. The tissue motion target information corresponding to different frequencies of shear waves can be distinguished and displayed using one of the following methods: graphs, colors, and lines.

[0120] When the tissue motion image includes at least two frames, displaying the tissue motion image involves dynamically displaying the at least two frames of tissue motion image in chronological order, that is, displaying the tissue motion image as a video at a preset frame rate; alternatively, the at least two frames of tissue motion image can be cumulatively displayed in chronological order, for example, as... Figure 5A and Figure 5B The image shows multiple frames of motion images accumulated and displayed on the screen in chronological order.

[0121] In another embodiment, such as Figure 6A As shown, a single frame of tissue motion image can simultaneously reflect tissue motion target information of at least two different frequencies of shear waves at multiple preset times.

[0122] Figure 6A The horizontal and vertical axes of the tissue motion image shown correspond to the width and depth directions of the tissue, respectively. Based on the tissue motion target information corresponding to each frequency of shear wave, the propagation position of the shear wave at each preset time can be calculated. By plotting the curves representing the shear wave propagation positions on the same tissue motion image, the following can be obtained: Figure 6A The image shown is a static tissue motion image. Figure 6AThe propagation position of shear waves is abstracted as a curve, with solid and dashed lines corresponding to two different frequencies of shear waves, namely frequency one and frequency two. Alternatively, the tissue motion target information of shear waves at different frequencies can be distinguished and displayed using at least one of the following methods: graphs, colors, or lines. If a shear wave of a certain frequency propagates faster, its propagation position can be observed to be further forward at the same time, and a distance difference will appear between shear waves of different frequencies. Generally speaking, the stronger the tissue viscosity, the greater the distance difference between two shear waves of different frequencies, thus allowing the magnitude of tissue viscosity to be determined from the tissue motion image.

[0123] For example, the intervals between preset time points in a tissue motion image can be equal, such as 1 ms, 2 ms, or 3 ms. For instance, for a tissue with uniform viscoelasticity, the propagation speed of the shear wave is uniform, and therefore the propagation distance of the shear wave within equal time intervals will also be uniform. Thus, the uniformity of the tissue's viscoelasticity can be intuitively determined based on the tissue motion image. Of course, the intervals between preset time points can also be unequal.

[0124] As another alternative implementation, organizing motion images can reflect the time information required for at least two different frequencies of shear waves to propagate to at least two preset propagation locations, such as... Figure 6B As shown. Figure 6B The tissue motion images shown are similar to those shown below. Figure 6A The tissue motion images shown are similar, except that the horizontal and vertical coordinates of the tissue motion images correspond to propagation time and depth, respectively. Figure 6B Different lines in the diagram correspond to the time required for shear waves of different frequencies to propagate to different distances; solid lines correspond to frequency three, and dashed lines correspond to frequency four. However, besides using lines to distinguish the tissue movement target information of shear waves of different frequencies, this information can also be distinguished using at least one of the following: graph and color. If a shear wave of a certain frequency propagates faster, it can be observed that it requires less time to travel the same distance. Generally, the stronger the tissue viscosity, the greater the difference in propagation time between two shear waves of different frequencies.

[0125] When tissue motion target information of at least two different frequencies of shear waves is output numerically, feature parameters reflecting the viscous characteristics of the target region can be generated based on this information, and the feature parameters can be displayed. These feature parameters can be obtained based on the aforementioned tissue motion image, and the tissue motion image can be output along with the feature parameters. Alternatively, the feature parameters can be obtained solely from the tissue motion information, without displaying the tissue motion image.

[0126] For example, the characteristic parameters include at least one of the following: the interval between the propagation positions of shear waves of different frequencies at the same time; the ratio between this interval and the propagation distance of a shear wave of one of the different frequencies within a preset time; and the time difference between the times required for shear waves of different frequencies to propagate to the same preset propagation position. For example, refer to Figure 6A Because the stronger the viscosity of the tissue, the greater the difference in propagation distance between two shear waves of different frequencies, the characteristic parameter can be... Figure 6A The distance Δd between two shear waves of different frequencies at the same time; the characteristic parameter can also be related to the propagation distance of the shear waves of different frequencies within the same time interval (i.e., Figure 6A The shear wave frequency components, represented by dashed lines, are related to the propagation distance D during the time interval t1 to t2; the characteristic parameter can be the ratio Δd / D between Δd and D. Since the stronger the tissue viscosity, the greater the difference in propagation speed between two shear waves of different frequencies, the characteristic parameter can also be the time difference between the times required for shear waves of different frequencies to propagate to the same predetermined propagation position. For example, see [reference needed]. Figure 6B This time difference can be the time difference Δt between the time required for the shear waves of frequency three and frequency four to propagate to d1.

[0127] Since the propagation state of shear waves is affected by tissue viscosity, the characteristic parameters can also be other parameters related to the propagation distance, propagation speed, propagation time, etc. of shear waves.

[0128] The above exemplarily illustrates a viscoelasticity measurement method 200 according to an embodiment of this application. Based on the above description, the viscoelasticity measurement method 200 according to an embodiment of this application reflects the viscous characteristics of a tissue through tissue motion target information of at least two different frequencies of shear waves.

[0129] This application also provides an ultrasonic imaging system for implementing the above-described viscoelasticity measurement method 200. The ultrasonic imaging system includes an ultrasonic probe, a transmitting circuit, a receiving circuit, a processor, and a display. Now referring back to... Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown is described above. As described above, the ultrasound imaging system 100 may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118; the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122, and the relevant descriptions of each component can be found above.

[0130] Specifically, the ultrasonic probe 110 is used to generate shear waves propagating within the target area of ​​the object being measured; the transmitting circuit 112 is used to excite the ultrasonic probe 110 to emit ultrasonic waves that track the shear waves towards the target area; the receiving circuit 114 is used to control the ultrasonic probe 110 to receive the ultrasonic echoes returned from the target area to obtain ultrasonic echo data; the processor 116 is used to execute the steps of the viscoelastic measurement method 200, namely: obtaining tissue motion information during the propagation of the shear waves based on the ultrasonic echo data; extracting tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information; and controlling the display 118 to output the tissue motion target information corresponding to the at least two different frequencies of shear waves, wherein the tissue motion target information reflects the viscous characteristics of the target area.

[0131] In one embodiment, the processor 116 controls the display 118 to output tissue motion target information corresponding to the at least two different frequencies of shear waves, including: controlling the display 118 to output the tissue motion target information of the at least two different frequencies of shear waves in a graphical or numerical manner.

[0132] In one embodiment, the processor 116 is further configured to generate a tissue motion image based on the tissue motion target information of the at least two different frequencies of shear waves, and to output the tissue motion target information of the at least two different frequencies of shear waves in a graphical manner, including controlling the display 118 to display the tissue motion image.

[0133] In one embodiment, the tissue motion image includes at least one frame, and each frame of the tissue motion image reflects tissue motion target information corresponding to a shear wave of at least one frequency at a preset time.

[0134] In another embodiment, a single frame of tissue motion image simultaneously reflects tissue motion target information corresponding to at least two different frequencies of shear waves at multiple preset times.

[0135] In yet another embodiment, the tissue motion image reflects the time information required for the at least two different frequencies of shear waves to propagate to at least two predetermined propagation locations.

[0136] In one embodiment, the processor 116 is further configured to generate feature parameters reflecting the viscous characteristics of the target region based on the tissue motion target information of the at least two different frequencies of shear waves, and to output the tissue motion target information of the at least two different frequencies of shear waves in a numerical manner, including controlling the display 118 to display the feature parameters.

[0137] For example, the characteristic parameters include at least one of the following: the interval between the propagation positions of shear waves of different frequencies at the same time; the ratio between the interval and the propagation distance of a shear wave of one frequency within a preset time; and the time difference between the time required for shear waves of different frequencies to propagate to the same preset propagation position.

[0138] The above only describes the main functions of each component of the ultrasound imaging system 100; for more details, please refer to the relevant description of the viscoelasticity measurement method 200. The ultrasound imaging system of this application embodiment can reflect the viscous characteristics of tissue through tissue motion target information from at least two different frequencies of shear waves.

[0139] The following is a reference to the appendix. Figure 7 A viscoelasticity measurement method according to another embodiment of this application is described. Figure 7 A schematic flowchart of a viscoelasticity measurement method 700 according to another embodiment of this application is shown. Figure 7 As shown, the viscoelasticity measurement method 700 of this application embodiment includes the following steps:

[0140] Step S710: At least two different frequencies of shear waves propagating within the target area of ​​the object being measured are generated sequentially.

[0141] Step S720: Emit ultrasonic waves that track at least two different frequencies of shear waves toward the target area, and receive ultrasonic echoes returned from the target area to obtain ultrasonic echo data.

[0142] Step S730: Obtain tissue motion target information corresponding to the at least two different frequencies of shear waves based on the ultrasound echo data;

[0143] Step S740: Output tissue motion target information corresponding to the at least two different frequencies of shear waves, the tissue motion target information reflecting the viscous characteristics of the target area.

[0144] like Figure 7The viscoelasticity measurement method 700 shown differs from the viscoelasticity measurement method 200 described above in that, instead of extracting tissue motion target information of shear waves at different frequencies from tissue motion information, viscoelasticity measurement method 700 directly generates at least two different frequencies of shear waves in step S710. Specifically, different frequencies of shear waves can be generated by adjusting the emission interval of the ultrasonic driving pulse. For example, by continuously emitting ultrasonic driving pulses multiple times at a certain time interval PRT, the frequency of the generated shear waves will be concentrated at the frequency point of N / PRT. Therefore, different frequencies of shear waves can be generated by changing the length of PRT. Alternatively, a transient elastography method can be used, based on the vibration of the vibrator in the ultrasonic probe emitting vibrations at different frequencies to generate shear waves of different frequencies.

[0145] For each frequency of shear wave, ultrasonic waves tracking the shear wave are emitted towards the target region, and the ultrasonic echoes returned from the target region are received to obtain ultrasonic echo data. Based on the ultrasonic echo data corresponding to at least two different frequencies of shear waves, tissue motion target information corresponding to at least two different frequencies of shear waves is obtained. Finally, the tissue motion target information corresponding to at least two different frequencies of shear waves is output. In some embodiments, since the tissue motion information is related to the frequency of the shear wave, the frequency information of at least two different frequencies of shear waves can also be output. For example, the frequency information of at least two different frequencies of shear waves can be output simultaneously with the tissue motion target information of at least two different frequencies of shear waves.

[0146] For example, outputting tissue motion target information corresponding to at least two different frequencies of shear waves includes: outputting the tissue motion target information corresponding to at least two different frequencies of shear waves in a graphical or numerical manner. Specifically, outputting the tissue motion target information corresponding to at least two different frequencies of shear waves graphically includes: generating a tissue motion image based on the tissue motion information corresponding to the at least two different frequencies of shear waves, and displaying the tissue motion image. Outputting the tissue motion target information corresponding to at least two different frequencies of shear waves numerically includes: generating feature parameters reflecting the viscous characteristics of the target region based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and displaying the feature parameters. The form of the tissue motion image and the type of feature parameters are similar to those in the viscoelasticity measurement method 200, and can be referred to the above for details, which will not be repeated here.

[0147] The viscoelasticity measurement method 700 according to the embodiments of this application can reflect the viscous characteristics of a tissue through tissue motion target information corresponding to at least two different frequencies of shear waves.

[0148] This application also provides an ultrasonic imaging system for implementing the above-described viscoelasticity measurement method 700. The ultrasonic imaging system includes an ultrasonic probe, a transmitting circuit, a receiving circuit, a processor, and a display. Now referring back to... Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown is described above. As described above, the ultrasound imaging system 100 may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118; the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122, and the relevant descriptions of each component can be found above.

[0149] Specifically, the ultrasonic probe 110 is used to sequentially generate at least two different frequencies of shear waves propagating within the target area of ​​the object being measured; the transmitting circuit 112 is used to excite the ultrasonic probe 110 to transmit ultrasonic waves that track at least two different frequencies of shear waves towards the target area; the receiving circuit 114 is used to control the ultrasonic probe 110 to receive the ultrasonic echoes returned from the target area to obtain ultrasonic echo data; the processor 116 is used to: obtain tissue motion target information corresponding to at least two different frequencies of shear waves based on the ultrasonic echo data; and control the display 118 to output the tissue motion target information corresponding to at least two different frequencies of shear waves, wherein the tissue motion information is used to characterize the viscous characteristics of the target area.

[0150] In one embodiment, outputting tissue motion information during the propagation of at least two different frequencies of shear waves includes: outputting tissue motion target information corresponding to at least two different frequencies of shear waves in a graphical or numerical manner.

[0151] In one embodiment, the processor 116 is further configured to generate a tissue motion image based on tissue motion target information corresponding to at least two different frequencies of shear waves, and to output the tissue motion target information corresponding to at least two different frequencies of shear waves in a graphical manner, including controlling the display 118 to display the tissue motion image.

[0152] In one embodiment, the processor 116 is further configured to generate feature parameters reflecting the viscous characteristics of the target region based on tissue motion target information corresponding to at least two different frequencies of shear waves, and to output the tissue motion target information corresponding to at least two different frequencies of shear waves in a numerical manner, including controlling the display 118 to display the feature parameters.

[0153] The above only describes the main functions of each component of the ultrasound imaging system 100; for more details, please refer to the relevant description of the viscoelasticity measurement method 700. The ultrasound imaging system of this application embodiment can reflect the viscous characteristics of tissue through tissue motion target information corresponding to at least two different frequency shear waves.

[0154] The following is a reference to the appendix. Figure 8 A viscoelasticity measurement method according to another embodiment of this application is described. Figure 8 A schematic flowchart of a viscoelasticity measurement method 800 according to another embodiment of this application is shown. Figure 8 As shown, the viscoelasticity measurement method 800 of this application embodiment includes the following steps:

[0155] Step S810: Generate a shear wave that propagates in the target area of ​​the object being measured;

[0156] Step S820: Transmit ultrasonic waves that track the shear wave to the target area and receive the ultrasonic echoes returned from the target area to obtain ultrasonic echo data.

[0157] Step S830: Obtain tissue motion information corresponding to the shear wave based on the ultrasound echo data;

[0158] Step S840: Extract tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information;

[0159] Step S850: Generate feature parameters reflecting the viscous characteristics of the target region based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and display the feature parameters.

[0160] like Figure 8 The viscoelasticity measurement method 800 shown differs from the viscoelasticity measurement method 200 described above in that the viscoelasticity measurement method 800 can directly generate feature parameters based on tissue motion target information corresponding to at least two different frequencies of shear waves. For example, the viscoelasticity measurement method 800 does not require generating new parameters (e.g., shear wave velocity) based on the tissue motion target information corresponding to the at least two different frequencies of shear waves before further generating feature parameters. Instead, it directly calculates and generates feature parameters based on the tissue motion target information corresponding to the at least two different frequencies of shear waves after obtaining it. Apart from this, steps S810 to S840 are generally similar to steps S210 to S240 of the viscoelasticity measurement method 200.

[0161] In one embodiment, the characteristic parameters include at least one of the following: the interval between the propagation positions of shear waves of different frequencies at the same time; the ratio between the interval and the propagation distance of a shear wave of one frequency in the different frequencies within a preset time; and the time difference between the time required for shear waves of different frequencies to propagate to the same preset propagation position.

[0162] In one embodiment, in addition to outputting the aforementioned characteristic parameters, the viscoelasticity measurement method 800 further includes outputting tissue motion target information corresponding to the at least two shear waves of different frequencies. This tissue motion target information can be output as an image, including but not limited to the tissue motion image described in the viscoelasticity measurement method 200; or it can be output numerically. For example, the characteristic parameters from step S850 can be displayed simultaneously with the tissue motion target information of the at least two shear waves of different frequencies.

[0163] In some embodiments, since tissue motion information is related to the frequency of shear waves, frequency information of at least two different shear waves can also be output. For example, while outputting tissue motion target information of at least two different shear waves, frequency information of at least two different shear waves can also be output.

[0164] Furthermore, the viscoelasticity measurement method 800 shares many similarities with the viscoelasticity measurement method 200 described above, which can be referred to above for details and will not be repeated here. The viscoelasticity measurement method 800 according to embodiments of this application can generate characteristic parameters based on tissue motion target information corresponding to at least two different frequencies of shear waves, thereby reflecting the viscous characteristics of the tissue.

[0165] This application also provides an ultrasonic imaging system for implementing the above-described viscoelasticity measurement method 800. The ultrasonic imaging system includes an ultrasonic probe, a transmitting circuit, a receiving circuit, a processor, and a display. Now, referring back to... Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown is described above. As described above, the ultrasound imaging system 100 may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118; the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122, and the relevant descriptions of each component can be found above.

[0166] Specifically, the ultrasonic probe 110 is used to generate shear waves propagating within the target area of ​​the object being measured; the transmitting circuit 112 is used to excite the ultrasonic probe 110 to emit ultrasonic waves that track the shear waves towards the target area; the receiving circuit 114 is used to control the ultrasonic probe 110 to receive the ultrasonic echoes returned from the target area to obtain ultrasonic echo data; the processor 116 is used to obtain tissue motion information corresponding to the shear waves based on the ultrasonic echo data; extract tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information; generate feature parameters reflecting the viscous characteristics of the target area based on the tissue motion target information corresponding to at least two different frequencies of shear waves; and control the display to show the feature parameters.

[0167] The above only describes the main functions of each component of the ultrasound imaging system 100; for more details, please refer to the relevant description of the viscoelasticity measurement method 800. The ultrasound imaging system of this application embodiment can generate characteristic parameters based on tissue motion target information corresponding to at least two different frequencies of shear waves to reflect the viscous characteristics of the tissue.

[0168] The following is a reference to the appendix. Figure 9 A viscoelasticity measurement method according to another embodiment of this application is described. Figure 9 A schematic flowchart of a viscoelasticity measurement method 900 according to another embodiment of this application is shown. Figure 9 As shown, the viscoelasticity measurement method 900 of this application embodiment includes the following steps:

[0169] Step S910: At least two different frequencies of shear waves propagating in the target area of ​​the object under test are generated sequentially.

[0170] Step S920: Emit ultrasonic waves that track at least two different frequencies of shear waves toward the target area, and receive ultrasonic echoes returned from the target area to obtain ultrasonic echo data.

[0171] Step S930: Obtain tissue motion target information corresponding to the at least two different frequencies of shear waves based on the ultrasound echo data;

[0172] Step S940: Generate feature parameters reflecting the viscous characteristics of the target region based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and display the feature parameters.

[0173] like Figure 9 The viscoelasticity measurement method 900 shown differs from the viscoelasticity measurement method 800 described above in that, instead of extracting tissue motion target information of shear waves of different frequencies from tissue motion information, viscoelasticity measurement method 900 directly generates at least two different frequencies of shear waves in step S910. Specifically, different frequencies of shear waves can be generated by adjusting the emission interval of the ultrasonic driving pulse. Alternatively, a transient elastography method can be used, based on the vibration of the vibrator in the ultrasonic probe emitting vibrations of different frequencies to generate shear waves of different frequencies. Apart from this, viscoelasticity measurement method 900 is largely similar to viscoelasticity measurement method 800 described above, and will not be elaborated further here.

[0174] According to the embodiments of this application, the viscoelasticity measurement method 900 generates characteristic parameters based on tissue motion target information corresponding to at least two different frequencies of shear waves, so as to reflect the viscous characteristics of the tissue.

[0175] This application also provides an ultrasonic imaging system for implementing the above-described viscoelasticity measurement method 900. The ultrasonic imaging system includes an ultrasonic probe, a transmitting circuit, a receiving circuit, a processor, and a display. Now, referring back to... Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown is described above. As described above, the ultrasound imaging system 100 may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118; the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122, and the relevant descriptions of each component can be found above.

[0176] Specifically, the ultrasonic probe 110 is used to sequentially generate at least two different frequencies of shear waves propagating within the target area of ​​the object being measured; the transmitting circuit 112 is used to excite the ultrasonic probe 110 to emit ultrasonic waves that track at least two different frequencies of shear waves towards the target area; the receiving circuit 114 is used to control the ultrasonic probe 110 to receive ultrasonic echoes returned from the target area to obtain ultrasonic echo data; the processor 116 is used to obtain tissue motion target information corresponding to the at least two different frequencies of shear waves based on the ultrasonic echo data; and to generate feature parameters reflecting the viscous characteristics of the target area based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and control the display to display the feature parameters.

[0177] The ultrasound imaging system of this application embodiment can generate feature parameters based on tissue motion target information corresponding to at least two different frequencies of shear waves, so as to reflect the viscous characteristics of the tissue.

[0178] The following is a reference to the appendix. Figure 10 A viscoelasticity measurement method according to another embodiment of this application is described. Figure 10 A schematic flowchart of a viscoelasticity measurement method 1000 according to another embodiment of this application is shown. Figure 10 As shown, the viscoelasticity measurement method 1000 of this application embodiment includes the following steps:

[0179] Step S1010: Generate a shear wave of the target frequency that propagates in the target area of ​​the object being measured.

[0180] Step S1020: Emit an ultrasonic wave that tracks the target frequency of a shear wave to the target area, and receive the ultrasonic echo returned from the target area to obtain ultrasonic echo data.

[0181] Step S1030: Obtain tissue motion information corresponding to the shear wave at the target frequency based on the ultrasound echo data;

[0182] Step S1040: Output tissue motion information corresponding to the shear wave of the target frequency, wherein the tissue motion information is used to reflect the viscous characteristics of the target region.

[0183] Similar to the viscoelasticity measurement method described above, the viscoelasticity measurement method 1000 in this embodiment also utilizes the influence of tissue viscosity on tissue motion caused by shear wave propagation, reflecting the viscous characteristics of the tissue based on the tissue motion information. The difference lies in that the viscoelasticity measurement method 1000 does not reflect the viscous characteristics of the target region through tissue motion information corresponding to two different frequencies of shear waves, but rather through tissue motion information corresponding to a shear wave of the target frequency. Since the viscosity of the target region varies, the tissue motion information caused by the propagation of shear waves of the same frequency also differs. Therefore, the tissue motion information caused by a shear wave of the target frequency propagating in a reference tissue with known viscous characteristics can be obtained in advance, and the tissue motion information of the target region can be compared with the motion information of the reference tissue to determine the viscosity magnitude of the target region.

[0184] Since the frequency of the shear wave also affects tissue motion information, in one embodiment, while outputting the tissue motion information corresponding to the shear wave at the target frequency, the frequency information of the shear wave at the target frequency can also be displayed. This allows users to easily extract the motion information corresponding to the reference tissue at the pre-acquired target frequency.

[0185] In some embodiments, tissue motion information corresponding to the target frequency can be compared and displayed with motion information of a reference tissue having known viscous characteristics. The comparison between the two reflects the viscous characteristics of the target region. There can be one or more reference tissues, each with a specific viscous characteristic. The tissue motion information of the target region can be compared with the motion information of multiple reference tissues to find the reference tissue whose viscous characteristics are closest to those of the target region.

[0186] In some embodiments, when the target frequency is a single frequency, tissue motion information of the target region at at least two different times can be compared and displayed, and the magnitude of tissue viscosity can be determined based on the differences between the tissue motion information at different times. For example, the magnitude of tissue viscosity can be determined by acquiring tissue motion information of the target region of the test object at at least two different times at a single frequency, and then using the tissue motion information at these at least two different times.

[0187] The viscoelasticity measurement method 1000 according to the embodiments of this application can reflect the viscous characteristics of the target region through tissue motion information corresponding to shear waves at the target frequency.

[0188] This application also provides an ultrasonic imaging system for implementing the above-described viscoelasticity measurement method 1000. The ultrasonic imaging system includes an ultrasonic probe, a transmitting circuit, a receiving circuit, a processor, and a display. Now, referring back to... Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown is described above. As described above, the ultrasound imaging system 100 may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118; the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122, and the relevant descriptions of each component can be found above.

[0189] Specifically, the ultrasonic probe 110 is used to generate a shear wave of a target frequency that propagates in the target area of ​​the object being measured; the transmitting circuit 112 is used to excite the ultrasonic probe 110 to transmit ultrasonic waves that track the shear wave of the target frequency to the target area; the receiving circuit 114 is used to control the ultrasonic probe 110 to receive the ultrasonic echo returned from the target area to obtain ultrasonic echo data; the processor 116 is used to obtain tissue motion information corresponding to the shear wave of the target frequency based on the ultrasonic echo data; and output the tissue motion information corresponding to the shear wave of the target frequency, wherein the tissue motion information is used to reflect the viscous characteristics of the target area.

[0190] The above only describes the main functions of each component of the ultrasound imaging system 100; for more details, please refer to the relevant description of the viscoelasticity measurement method 1000. The ultrasound imaging system of this application embodiment can reflect the viscous characteristics of the target region through tissue motion information corresponding to shear waves at the target frequency.

[0191] Furthermore, according to embodiments of this application, a storage medium is also provided, on which program instructions are stored. When executed by a computer or processor, these program instructions are used to perform corresponding steps of the viscoelasticity measurement method of this application. The storage medium may, for example, include a memory card of a smartphone, a storage component of a tablet computer, a hard disk of a personal computer, a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a portable compact disc read-only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer-readable storage medium may be any combination of one or more computer-readable storage media.

[0192] Furthermore, according to embodiments of this application, a computer program is also provided, which can be stored on a cloud or local storage medium. When this computer program is run by a computer or processor, it is used to perform the corresponding steps of the viscoelasticity measurement method of the embodiments of this application.

[0193] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of this application. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of this application. All such changes and modifications are intended to be included within the scope of this application as claimed in the appended claims.

[0194] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0195] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is merely a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another apparatus, or some features may be ignored or not executed.

[0196] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0197] Similarly, it should be understood that, in order to streamline this application and aid in understanding one or more of the various inventive aspects, features of this application may sometimes be grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of this application. However, this approach should not be construed as reflecting an intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with features fewer than all features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of this application.

[0198] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0199] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0200] The various component embodiments of this application can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to the embodiments of this application. This application can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such an implementation of this application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0201] It should be noted that the above embodiments are illustrative of this application and not limiting of it, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by 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.

[0202] The above description is merely a specific embodiment or illustration of the embodiments of this application. The scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. The scope of protection of this application shall be determined by the scope of the claims.

Claims

1. A viscoelasticity measurement method characterized by, The viscoelasticity measurement method includes: Shear waves are generated and propagate within the target area of ​​the object being measured; An ultrasonic wave that tracks the shear wave is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data. Tissue motion information during the propagation of the shear wave is obtained based on the ultrasound echo data; Extract tissue motion target information corresponding to at least two different frequencies of shear waves from the tissue motion information; The tissue motion target information corresponding to the at least two different frequencies of shear waves is output in a graphical manner, wherein the tissue motion target information is used to reflect the viscous characteristics of the target region; The graphical output of tissue motion target information corresponding to the at least two different frequencies of shear waves includes: A tissue motion image is generated based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and the tissue motion image is displayed. The tissue motion image reflects the propagation position of the at least two different frequencies of shear waves at the same time, and the horizontal and vertical coordinates of the tissue motion image correspond to the width and depth directions of the tissue, respectively. Alternatively, the tissue motion image reflects the time information required for the at least two different frequencies of shear waves to propagate to the same distance, and the horizontal and vertical axes of the tissue motion image correspond to the propagation time and the depth direction of the tissue, respectively.

2. The viscoelasticity measurement method according to claim 1, wherein The step of outputting the tissue motion target information corresponding to the at least two different frequencies of shear waves in a numerical manner further includes: Based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, feature parameters reflecting the viscous characteristics of the target region are generated and displayed.

3. The viscoelasticity measurement method according to claim 1, wherein The tissue motion image includes at least one frame, and each frame of the tissue motion image reflects the tissue motion target information corresponding to at least one frequency of shear wave at a preset time.

4. The viscoelastic measurement method according to claim 3, wherein When the tissue motion image includes at least two frames, displaying the tissue motion image includes dynamically displaying at least two frames of tissue motion images in chronological order, or cumulatively displaying at least two frames of tissue motion images in chronological order.

5. The viscoelastic measurement method according to claim 3, wherein Each frame of the tissue motion image reflects the tissue motion target information corresponding to a shear wave of a certain frequency at a preset time. At the same preset time, target tissue motion image frames corresponding to shear waves of different frequencies are displayed in different windows simultaneously. Alternatively, each frame of the tissue motion image reflects tissue motion target information corresponding to at least two different frequencies of shear waves at a preset time, and target tissue motion image frames corresponding to at least two different frequencies of shear waves at different times are displayed in the same window.

6. The viscoelastic measurement method according to claim 1, wherein A single frame of the tissue motion image simultaneously reflects tissue motion target information corresponding to at least two different frequencies of shear waves at multiple preset times.

7. The viscoelastic measurement method according to claim 6, wherein The intervals between the multiple preset times are either equal or unequal.

8. The viscoelastic measurement method according to claim 1, wherein The tissue motion target information corresponding to the at least two different frequencies of shear waves is displayed in a distinguished manner using at least one of the following methods: graphs, colors, and lines.

9. The viscoelastic measurement method according to claim 1, wherein The feature parameters include at least one of the following: The distance between the propagation positions of shear waves of different frequencies at the same moment; The ratio between the interval distance and the propagation distance of the shear wave at one of the different frequencies within a preset time; The time difference between the time required for shear waves of different frequencies to propagate to the same predetermined propagation position.

10. The viscoelastic measurement method according to any one of claims 1 to 9, characterized by, The tissue motion information includes at least one of tissue displacement, tissue motion velocity, and tissue acceleration.

11. The viscoelastic measurement method according to claim 1, wherein The extraction of tissue motion target information from the tissue motion information, comprising at least two different frequencies of shear waves, includes: The tissue motion information is filtered using at least two different frequency filters to extract the tissue motion target information corresponding to the at least two different frequency shear waves.

12. A viscoelasticity measuring method characterized by, The viscoelasticity measurement method includes: At least two different frequencies of shear waves are generated sequentially in the target area of ​​the object being tested; An ultrasonic wave that tracks at least two different frequencies of shear waves is emitted toward the target area, and the ultrasonic echo returned from the target area is received to obtain ultrasonic echo data. Based on the ultrasound echo data, obtain tissue motion target information corresponding to the at least two different frequencies of shear waves; Outputting the tissue motion target information corresponding to the at least two different frequencies of shear waves in a graphical manner, wherein the tissue motion target information is used to reflect the viscous characteristics of the target region; the graphical output of the tissue motion target information corresponding to the at least two different frequencies of shear waves includes: A tissue motion image is generated based on the tissue motion target information corresponding to the at least two different frequencies of shear waves, and the tissue motion image is displayed. The tissue motion image reflects the propagation position of the at least two different frequencies of shear waves at the same time, and the horizontal and vertical coordinates of the tissue motion image correspond to the width and depth directions of the tissue, respectively. Alternatively, the tissue motion image reflects the time information required for the at least two different frequencies of shear waves to propagate to the same distance, and the horizontal and vertical axes of the tissue motion image correspond to the propagation time and the depth direction of the tissue, respectively.

13. The viscoelastic measurement method according to claim 12, wherein, The method further includes: Based on the tissue motion information corresponding to the at least two different frequencies of shear waves, feature parameters reflecting the viscous characteristics of the target region are generated and displayed.

14. The viscoelastic measurement method according to any one of claims 1, 12, characterized by, The method further includes: Acquire and output the frequency information of the at least two different shear waves.

15. The viscoelastic measurement method according to claim 14, wherein The output of frequency information for the at least two different frequencies of shear waves includes: While outputting the tissue motion target information of the at least two different frequencies of shear waves, the frequency information of the at least two different frequencies of shear waves is also output.

16. An ultrasound imaging system, characterized by The ultrasound imaging system includes: An ultrasonic probe is used to generate shear waves that propagate within the target area of ​​the object being measured. A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the shear wave toward the target area; A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data. A processor for executing the viscoelasticity measurement method according to any one of claims 1-11 and 14-15.

17. An ultrasound imaging system, characterized by The ultrasound imaging system includes: An ultrasonic probe is used to sequentially generate at least two different frequencies of shear waves that propagate within a target area of ​​the object being measured. A transmitting circuit is used to excite the ultrasonic probe to emit ultrasonic waves that track the at least two different frequencies of shear waves toward the target region; A receiving circuit is used to control the ultrasonic probe to receive the ultrasonic echo returned from the target area in order to obtain ultrasonic echo data. A processor for performing the viscoelasticity measurement method as described in any one of claims 12-15.

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