Ultrasonic elastography method and ultrasonic imaging equipment

Abstract

The embodiment of the invention discloses an ultrasonic elastography method and ultrasonic imaging equipment. In the embodiment of the invention, ultrasonic imaging equipment can respectively obtain a first shear wave elasticity result and a first strain elasticity result of an external area of a focus in target tissue of a testee and obtain a second strain elasticity result of an internal area of the focus in the target tissue; a quantitative elasticity result for the internal region of the lesion is determined based on the first shear wave elasticity result, the first strain elasticity result, and the second strain elasticity result. The shear wave elasticity result and the strain elasticity result of the external region of the focus and the strain elasticity result of the internal region of the focus are accurate, so that the quantitative elasticity result of the internal region of the focus is calculated according to the results; compared with the method of directly measuring the shear wave elasticity of the internal area of the focus, the method has the advantages that the obtained result is more accurate, and the form and boundary of the focus can be presented more accurately.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of medical equipment, and specifically to an ultrasonic elastic imaging method and an ultrasonic imaging device. Background Art

[0002] Ultrasonic elastography can non-invasively extract and image the elasticity or hardness and softness information of human tissues, making up for the deficiency of traditional ultrasonic medical imaging that cannot extract mechanical information. It plays an increasingly important role in various clinical scenarios such as differentiation of benign and malignant tumors, assessment of liver fibrosis, vascular sclerosis, muscle and nerve damage, etc.

[0003] The elastic imaging method commonly used in clinical liver examination is mainly shear wave elastic imaging, which generates shear waves inside the liver tissue based on acoustic radiation force, detects its propagation process through ultrasound, and calculates physical quantities such as shear wave propagation velocity and Young's modulus for imaging, thereby quantitatively measuring the elastic parameters of liver tissue. This method belongs to quantitative imaging and has significant advantages in evaluating the progression and severity of chronic liver fibrosis. Therefore, it is widely used in liver clinics and is widely praised.

[0004] However, since the shear wave source generated inside the tissue is often only at a depth of microns, for example, only ten microns, this has limited penetration for large-area and high-hardness lesions (such as malignant cancer). For focal liver tumors, the propagation of shear waves is often difficult to penetrate, resulting in poor performance of shear wave elastography, inability to obtain accurate shear wave measurement results inside the lesion, and difficulty in accurately presenting the morphology and boundaries of the lesion. Summary of the invention

[0005] The embodiments of the present application provide an ultrasonic elastic imaging method and an ultrasonic imaging device for improving the accuracy and reliability of shear wave elasticity results of the internal area of ​​a tissue lesion.

[0006] A first aspect of an embodiment of the present application provides an ultrasonic elastic imaging method, comprising:

[0007] Acquire an ultrasonic image of a target tissue, and determine an internal region of a lesion of the target tissue and an external region of the lesion according to the ultrasonic image;

[0008] emitting a first acoustic radiation force pulse to an outer region of the lesion to induce displacement or strain of tissue corresponding to the outer region of the lesion and generate a first shear wave propagating in the outer region of the lesion;

[0009] Transmitting first ultrasonic waves at different times to the external area of ​​the lesion to detect the change in displacement or strain of the tissue corresponding to the external area of ​​the lesion and to track the first shear wave propagating in the external area of ​​the lesion, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals;

[0010] Based on the first ultrasonic echo signal, obtaining a first strain elasticity result of the outer area of ​​the lesion; and based on the first ultrasonic echo signal, obtaining a first shear wave elasticity result of the outer area of ​​the lesion;

[0011] emitting a second acoustic radiation force pulse to the inner region of the lesion to induce displacement or strain of tissue corresponding to the inner region of the lesion;

[0012] Transmitting second ultrasonic waves at different times to the internal area of ​​the lesion to detect the change in displacement or the change in strain of the tissue corresponding to the internal area of ​​the lesion, and receiving echoes of the second ultrasonic waves at different times to obtain second ultrasonic echo signals;

[0013] Based on the second ultrasonic echo signal, obtaining a second strain elasticity result of the internal area of ​​the lesion;

[0014] determining a quantitative elastic result of an inner region of the lesion based on the first strain elastic result, the first shear wave elastic result, and the second strain elastic result;

[0015] The ultrasound image and the quantitative elasticity results are displayed.

[0016] A second aspect of the embodiment of the present application provides an ultrasonic elastic imaging method, comprising:

[0017] Acquire an ultrasonic image of a target tissue, wherein the ultrasonic image includes a first region of interest and a second region of interest of the target tissue;

[0018] Inducing displacement or strain in tissues corresponding to the first region of interest and the second region of interest;

[0019] Transmitting first ultrasonic waves at different times to the first region of interest and the second region of interest to detect the displacement change or the strain change of the tissues corresponding to the first region of interest and the second region of interest, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals;

[0020] Based on the first ultrasonic echo signal, obtaining a first strain elasticity result of the first region of interest and a second strain elasticity result of the second region of interest;

[0021] generating a first shear wave that propagates in the first region of interest;

[0022] Transmitting a second ultrasonic wave to the first region of interest to track the first shear wave propagating in the first region of interest, and receiving an echo of the second ultrasonic wave to obtain a second ultrasonic echo signal;

[0023] obtaining a first shear wave elastic result of the first region of interest based on the second ultrasonic echo signal;

[0024] determining a quantitative elastic result of the second region of interest based on the first strain elastic result, the second strain elastic result, and the first shear wave elastic result;

[0025] The ultrasound image and the quantitative elasticity results are displayed.

[0026] A third aspect of the present application provides an ultrasonic imaging device, including:

[0027] Ultrasound probe;

[0028] A transmitting circuit, used for stimulating the ultrasonic probe to transmit ultrasonic waves to a target tissue of a subject;

[0029] A receiving circuit, used for controlling the ultrasonic probe to receive the echo of the ultrasonic wave returned by the target tissue to obtain an ultrasonic echo signal;

[0030] A processor is used to process the ultrasonic echo signal to obtain an ultrasonic image of the target tissue, and to perform the ultrasonic elastic imaging method described in the first aspect or the second aspect based on the ultrasonic image.

[0031] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0032] The ultrasonic imaging device can obtain the first shear wave elasticity result and the first strain elasticity result of the external area of ​​the lesion in the target tissue of the subject, and obtain the second strain elasticity result of the internal area of ​​the lesion in the target tissue, and determine the quantitative elasticity result of the internal area of ​​the lesion based on the first shear wave elasticity result, the first strain elasticity result and the second strain elasticity result. Since the shear wave elasticity result and the strain elasticity result of the external area of ​​the lesion and the strain elasticity result of the internal area of ​​the lesion are accurate, the quantitative elasticity result of the internal area of ​​the lesion calculated based on the above results is more accurate than the result obtained by directly measuring the shear wave elasticity of the internal area of ​​the lesion, and the morphology and boundary of the lesion can also be more accurately presented. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1A schematic block diagram of the structure of an ultrasonic imaging device in an embodiment of the present application;

[0034] Figure 2 A schematic diagram of a flow chart of the ultrasonic elastic imaging method in an embodiment of the present application;

[0035] Figure 3 It is an exemplary schematic diagram of the positions of the internal area of ​​the lesion and the external area of ​​the lesion in the ultrasound image in the embodiment of the present application;

[0036] Figure 4 An exemplary schematic diagram of the position of the target tissue used to calculate the shear wave elasticity result and the strain result in the embodiment of the present application;

[0037] Figure 5 A schematic diagram of a marking method for marking the internal area of ​​a lesion in an ultrasound image in an embodiment of the present application;

[0038] Figure 6 A schematic diagram of a marking method for marking an internal area and an external area of ​​a lesion in an ultrasound image in an embodiment of the present application;

[0039] Figure 7 This is another schematic diagram of the ultrasonic elastography method in the embodiment of the present application. DETAILED DESCRIPTION

[0040] The embodiments of the present application provide an ultrasonic elastic imaging method and an ultrasonic imaging device for improving the accuracy and reliability of shear wave elasticity results of the internal area of ​​a tissue lesion.

[0041] The terms "first", "second", "third", "fourth", etc. (if any) in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0042] See also Figure 1 In the embodiment of the present application, the ultrasonic imaging device includes:

[0043] The ultrasonic probe 110 , the transmitting circuit 112 , the receiving circuit 114 , the processor 118 and the display 120 . In addition, the ultrasonic probe 110 , the transmitting circuit 112 , the receiving circuit 114 , the processor 118 and the display 120 , and the transmitting / receiving selection switch 122 , the beamforming module 116 and the memory 124 may also be included.

[0044] The ultrasonic probe 110 can be any probe used for ultrasonic detection, such as a 2D ultrasonic probe and a 3D ultrasonic probe. Among them, the acoustic head part of the ultrasonic probe 110 can be an array composed of multiple array elements, such as multiple array elements arranged in a row to form a linear array, or arranged in a two-dimensional matrix to form a surface array, and multiple array elements can also form a convex array. The above-mentioned array elements are used to emit ultrasonic beams according to the excitation electrical signal, or to convert the received ultrasonic echoes into electrical signals. Therefore, each array element can be used to realize the mutual conversion between the electrical pulse signal and the ultrasonic beam, so as to realize the emission of ultrasonic waves to the target tissue of the human body, and can also be used to receive the echo of the ultrasonic wave reflected back by the tissue.

[0045] The transmitting circuit 112 is used to generate a transmitting sequence according to the control of the transmitting control module of the processor 118, and the transmitting sequence is used to control part or all of the multiple array elements to transmit ultrasonic waves to biological tissues.

[0046] The receiving circuit 114 is used to receive the electrical signal of the ultrasonic echo from the ultrasonic probe 110 , obtain the ultrasonic echo signal, and send the ultrasonic echo signal to the beamforming module 116 .

[0047] The beamforming module 116 is used to perform corresponding delay, weighted summation and beamforming processing on the signal output by the receiving circuit 114. Since the distances from the ultrasonic receiving point to the receiving array element in the measured tissue are different, the channel data of the same receiving point output by different receiving array elements have delay differences, and it is necessary to perform delay processing, align the phases, and perform weighted summation on the different channel data of the same receiving point to obtain the beamformed data.

[0048] Processor 118, which is connected to beamforming module 116, mainly performs detection, signal enhancement, data conversion and logarithmic compression on the beamformed data to form an ultrasound image. The ultrasound image obtained by processor 118 can be displayed on display 120 or stored in memory 124.

[0049] Optionally, the processor 118 may be at least one of an application specific integrated circuit (ASIC), a digital signal processor (DSP), a digital signal processing device (DSPD), a programmable logic device (PLD), a field programmable gate array (FPGA), a central processing unit (CPU), a controller, a microcontroller or a microprocessor, so that the processor 118 can control other components in the ultrasonic imaging device 100 to perform the ultrasonic imaging steps in various embodiments of this specification. The processor 118 may be a component, or may be a general term for a control device and a processing device in an ultrasonic imaging device that can control other components of the ultrasonic imaging device to perform various functions in various embodiments.

[0050] The display 120 is connected to the processor 118, and the display 120 may be a touch screen or a liquid crystal display, etc.; or, the display 120 may be an independent display such as a liquid crystal display or a television set independent of the ultrasound imaging system 100; or, the display 120 may be a display screen of an electronic device such as a smart phone or a tablet computer, etc. The number of the display 120 may be one or more.

[0051] In addition to the above structure, the ultrasonic imaging device 100 may also include a human-computer interaction device. Specifically, the human-computer interaction device may be a display 120. If all functions of the human-computer interaction device are integrated into the display 120, the display 120 may also provide a graphical interface for human-computer interaction to the user when displaying the ultrasonic image. One or more controlled objects are set on the graphical interface, and the user is provided with a human-computer interaction device to input operation instructions to control these controlled objects, thereby performing corresponding control operations. For example, an icon is displayed on the graphical interface, and the icon can be operated using the human-computer interaction device to perform specific functions, such as swapping the position of the image and / or enlarging a specific area for display.

[0052] The human-machine interaction device may also be other human-machine interaction devices other than the display 120. For example, the human-machine interaction device may include an input device, and the input device is used to detect the user's input information, and the input information may be, for example, instructions for editing and marking ultrasound images, or may also include other types of instructions. The input device may include a keyboard, a scroll wheel, a trackball, a mobile input device (such as a mobile device with a touch screen, a mobile phone, etc.), a multi-function knob, etc., or a combination of multiple thereof. The human-machine interaction device may also include an output device such as a printer.

[0053] The ultrasonic imaging device 100 may further include a memory 124, which is used to store instructions for processing execution, to store received ultrasonic echo signals, to store ultrasonic image data, etc. The memory 124 may be a volatile memory, such as a random access memory (RAM); or a non-volatile memory, such as a read-only memory (ROM), a flash memory, a hard disk drive (HDD) or a solid-state drive (SSD); or a combination of the above types of memory, and provides instructions and data to the processor.

[0054] It should be understood that Figure 1 The components included in the ultrasonic imaging device 100 shown are only exemplary, and the ultrasonic imaging device 100 may include more or fewer components, and the present application does not impose corresponding limitations on this.

[0055] Based on the specific structural composition of the aforementioned ultrasonic imaging device and the functions of each structure, the following further describes in detail the multiple embodiments and implementation methods of the ultrasonic elastic imaging method performed by the ultrasonic imaging device in the embodiment of the present application. Figure 2 In the embodiments of the present application, an embodiment of the ultrasound elastic imaging method includes:

[0056] 201. Acquire an ultrasonic image of a target tissue, and determine an internal region of a lesion of the target tissue and an external region of the lesion according to the ultrasonic image;

[0057] In this embodiment, the ultrasonic imaging device performs ultrasonic scanning on the target tissue of the subject under the scanning operation of the user to obtain an ultrasonic image of the target tissue, and determines the internal area of ​​the lesion and the external area of ​​the lesion in the target tissue based on the ultrasonic image.

[0058] The target tissue may be any organ tissue of the subject, for example, liver tissue. The ultrasonic imaging device determines the internal area and the external area of ​​the lesion in the ultrasonic image by using a pre-trained image recognition neural network model to identify the internal area and the external area of ​​the lesion; or the user marks the internal area and the external area of ​​the lesion on the ultrasonic image, and the ultrasonic imaging device determines the above two areas according to the user's instructions; or the above two methods are combined, that is, the ultrasonic imaging device automatically determines the above two areas, and if the user is not satisfied with the determination result of the ultrasonic imaging device, the user can also manually adjust the area determined by the ultrasonic imaging device. This embodiment does not limit the method by which the ultrasonic imaging device determines the internal area and the external area of ​​the lesion in the ultrasonic image.

[0059] For example, Figure 3 As shown, the internal area of ​​the lesion in the ultrasound image is the area surrounded by white lines, and the external area of ​​the lesion is other areas outside the area surrounded by white lines. These two areas can be determined automatically by the ultrasound imaging device or by the ultrasound imaging device according to user instructions.

[0060] 202. Emitting a first acoustic radiation force pulse to an outer region of the lesion to induce displacement or strain of tissue corresponding to the outer region of the lesion and generate a first shear wave propagating in the outer region of the lesion;

[0061] The ultrasound imaging device further determines the internal area and the external area of ​​the lesion in the target tissue based on the internal area and the external area of ​​the lesion in the ultrasound image, and emits a first acoustic radiation force impulse (ARFI) to the external area of ​​the lesion in the target tissue, such as a focused ultrasound shear wave push pulse (SWP wave for short). This pulse signal can cause displacement or strain of the tissue corresponding to the external area of ​​the lesion. In addition, based on the principle of acoustic radiation force, a force will also be generated inside the tissue, which will then generate the first shear wave that propagates in the external area of ​​the lesion.

[0062] 203. Transmitting first ultrasonic waves at different times to the external area of ​​the lesion to detect the change in displacement or strain of the tissue corresponding to the external area of ​​the lesion and to track the first shear wave propagating in the external area of ​​the lesion, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals;

[0063] 204. Based on the first ultrasonic echo signal, obtain a first strain elasticity result of the outer area of ​​the lesion; and based on the first ultrasonic echo signal, obtain a first shear wave elasticity result of the outer area of ​​the lesion;

[0064] Based on the effect of acoustic radiation force, while shear waves are generated in the external area of ​​the lesion, the force will also cause tissue displacement or strain near the shear wave source (usually within the focal area of ​​the acoustic radiation force pulse sound field). The greater the intensity of the acoustic radiation force pulse, the stronger the acoustic radiation force, and the greater the tissue displacement or strain near the shear wave source.

[0065] Therefore, in order to detect the displacement change or strain change of the tissue corresponding to the external area of ​​the lesion, the ultrasonic imaging device can transmit the first ultrasonic wave at different times to the external area of ​​the lesion, and receive the echo of the first ultrasonic wave at different times to obtain the first ultrasonic echo signal. The ultrasonic imaging device also obtains the first strain elastic result of the external area of ​​the lesion based on the first ultrasonic echo signal. The strain elastic result is realized by pressure elastic imaging. The specific imaging method is mainly to apply pressure to the target tissue through the ultrasonic probe, obtain two frames of ultrasonic echo information before and after the target tissue is compressed, and then calculate the displacement of the corresponding position before and after the compression through the ultrasonic echo signal, that is, the spatial position change information of the target tissue at two different times, and obtain the axial gradient of the displacement, and then obtain the strain elastic result of each point in the target tissue area. The strain elastic result can intuitively reflect the difference in hardness or elasticity between different tissues. Under the same external force compression, the greater the strain, the softer the tissue; the smaller the strain, the harder the tissue.

[0066] For example, an acoustic radiation force pulse is emitted to a certain position in the external area of ​​the lesion, and then ultrasound waves are emitted to the position at different times, such as at least two groups of ultrasound waves with an interval of 1ms, 2ms or 3ms, etc., and the echo signal of each group of ultrasound waves is received. Based on the echo signal of each group of ultrasound waves, the motion state of the tissue at the position is determined and the difference before and after is compared, and the strain elasticity result of the position can be calculated. According to the transformation relationship between physical quantities, the strain elasticity result can usually be obtained by using the spatial gradient calculation of the displacement result.

[0067] In addition, the first ultrasonic echo signal can also be used to track the first shear wave propagating in the external area of ​​the lesion. Therefore, the first shear wave elasticity result of the external area of ​​the lesion can also be obtained based on the first ultrasonic echo signal processing.

[0068] For example, in each of the above structures of the ultrasonic imaging device, the transducer in the ultrasonic probe 110 is also used to apply an acoustic radiation force pulse to the external area of ​​the lesion in the target tissue of the subject to generate shear waves. Specifically, in the shear wave elastic imaging process, the transducer in the ultrasonic probe applies an acoustic radiation force pulse to the external area of ​​the lesion to generate shear waves; the transmitting circuit 112 sends the delayed focused transmitting pulse to the ultrasonic probe 110 through the transmitting / receiving selection switch 122, and the ultrasonic probe 110 is stimulated by the transmitting pulse to transmit an ultrasonic beam to the external area of ​​the lesion to track the shear wave; after a certain delay, the ultrasonic probe 110 receives the ultrasonic echo with tissue information reflected from the external area of ​​the lesion, and reconverts the ultrasonic echo into an electrical signal. The receiving circuit 114 receives the electrical signal converted and generated by the ultrasonic probe 110, obtains the ultrasonic echo signal, and sends the ultrasonic echo signal to the beamforming module 116. The beamforming module 116 performs focusing delay, weighting and channel summing on the ultrasonic echo data, and then sends it to the processor 118. The processor 118 performs elastic imaging on the ultrasonic echo signal and calculates the shear wave elasticity results and strain elasticity results of the external area of ​​the lesion.

[0069] 205. Emitting a second acoustic radiation force pulse to the internal area of ​​the lesion to induce displacement or strain of tissue corresponding to the internal area of ​​the lesion;

[0070] The ultrasonic imaging device also determines the internal area of ​​the lesion in the target tissue of the subject based on the internal area of ​​the lesion in the ultrasonic image, and emits a second acoustic radiation force pulse to the internal area of ​​the lesion in the target tissue. The second acoustic radiation force pulse can induce displacement or strain in the tissue corresponding to the internal area of ​​the lesion in the target tissue.

[0071] 206. Transmitting second ultrasonic waves at different times to the internal area of ​​the lesion to detect displacement changes or strain changes of tissues corresponding to the internal area of ​​the lesion, and receiving echoes of the second ultrasonic waves at different times to obtain second ultrasonic echo signals;

[0072] 207. Obtain a second strain elasticity result of the internal area of ​​the lesion based on the second ultrasonic echo signal;

[0073] Similarly, the ultrasonic imaging device also transmits a second ultrasonic wave at different times to the internal area of ​​the lesion. The second ultrasonic wave is used to detect the displacement change or strain change of the tissue corresponding to the internal area of ​​the lesion, and receives the echo of the second ultrasonic wave at different times to obtain a second ultrasonic echo signal, and obtains a second strain elastic result of the internal area of ​​the lesion based on the second ultrasonic echo signal.

[0074] For example, a second acoustic radiation force pulse is emitted to the internal area of ​​the lesion to induce displacement or strain of tissue at an arbitrary position in the internal area of ​​the lesion, and then a second ultrasonic wave is emitted to the position at different times, such as at least two groups of ultrasonic waves with an interval of 1ms, 2ms or 3ms between the two groups of ultrasonic waves, and the echo signal of each group of ultrasonic waves is received. Based on the echo signal of each group of ultrasonic waves, the motion state of the tissue at the position is determined and the difference before and after is compared, and the strain elasticity result at the position can be calculated. According to the transformation relationship between physical quantities, the strain elasticity result can usually be obtained by using the spatial gradient calculation of the displacement result.

[0075] 208. Determine a quantitative elastic result of an internal area of ​​the lesion based on the first strain elastic result, the first shear wave elastic result, and the second strain elastic result;

[0076] Since the shear wave source generated inside the tissue is often only at a micron-level depth, for example, only ten microns in depth, this has limited penetration for large-area and high-hardness lesions (such as malignant cancer). For focal liver tumors, the propagation of shear waves is often difficult to penetrate, resulting in inaccurate shear wave measurement results in the internal area of ​​the lesion. To solve this technical problem, in this embodiment, since the tissue in the external area of ​​the lesion is relatively uniform and the hardness is usually relatively small, the detection of shear wave elasticity and strain elasticity is relatively reliable and accurate. However, the tumor tissue in the internal area of ​​the lesion is usually of high or uneven hardness. Although the generated shear wave cannot be well propagated, the strain or displacement value inside the sound field focusing area directly caused by the acoustic radiation force is relatively reliable. Therefore, the ultrasonic imaging device determines the quantitative elasticity result of the internal area of ​​the lesion based on the first strain elasticity result, the first shear wave elasticity result and the second strain elasticity result calculated in the above steps. Since the external area of ​​the lesion is generally a diffuse lesion or a uniform healthy tissue, the shear wave elasticity measurement of the external area of ​​the lesion can usually obtain a more accurate measurement result. Therefore, the shear wave elastic results and strain elastic results of the external area of ​​the lesion and the strain elastic results of the internal area of ​​the lesion are accurate. The shear wave elastic results of the internal area of ​​the lesion calculated based on the above results are more accurate than the results obtained by directly measuring the shear wave elasticity of the internal area of ​​the lesion.

[0077] The quantitative elastic result may be a quantitative elastic result such as shear wave propagation velocity, Young's modulus, shear modulus, etc., that is, the quantitative elastic result may be expressed as the above parameters.

[0078] 209. Displaying the ultrasound image and the quantitative elasticity result;

[0079] The ultrasonic imaging device can display the ultrasonic image of the target tissue of the subject, and display the quantitative elasticity results obtained by the above steps, so that the doctor can determine the location of the lesion and the shear wave elasticity results of the lesion based on the ultrasonic image.

[0080] In this embodiment, the ultrasonic imaging device can obtain the first shear wave elastic result and the first strain elastic result of the external area of ​​the lesion in the target tissue of the subject, and obtain the second strain elastic result of the internal area of ​​the lesion in the target tissue, and determine the quantitative elastic result of the internal area of ​​the lesion based on the first shear wave elastic result, the first strain elastic result and the second strain elastic result. Since the shear wave elastic result and the strain elastic result of the external area of ​​the lesion and the strain elastic result of the internal area of ​​the lesion are accurate, the quantitative elastic result of the internal area of ​​the lesion calculated according to the above results is more accurate than the result obtained by directly measuring the shear wave elasticity of the internal area of ​​the lesion, and the morphology and boundary of the lesion can also be more accurately presented.

[0081] The shear wave elastic result may include a Young's modulus result. According to Hooke's law, under a certain stress Stress, the strain elastic result Strain is inversely proportional to the Young's modulus result E, that is, it can be expressed as Stress=Strain*E. Based on this, in a preferred implementation of this embodiment, the acoustic radiation force generated by the first acoustic radiation force pulse on the first target position in the external area of ​​the lesion is the same as the acoustic radiation force generated by the second acoustic radiation force pulse on the second target position in the internal area of ​​the lesion, or the difference between the two is within a preset range. The first target position is the position corresponding to the first strain elastic result, and the second target position is the position corresponding to the second strain elastic result. Therefore, it can be ensured that the stress (i.e., the acoustic radiation force) induced by the first acoustic radiation force pulse to the first target position is the same or approximately the same as the stress induced by the second acoustic radiation force pulse to the second target position. When the stress is the same or approximately the same, that is, the stress OutStress in the external area of ​​the lesion is equal to the stress InStress in the internal area of ​​the lesion, and then according to the formula Stress=Strain*E, it can be obtained:

[0082] OutStrain*OutE=Instrain(i)*InE(i);

[0083] Among them, OutStrain refers to the first strain elastic result, OutE refers to the first shear wave elastic result, OutStrain*OutE is the external area stress OutStress of the lesion; Instrain(i) refers to the second strain elastic result, InE(i) refers to the quantitative elastic result, Instrain(i)*InE(i) is the internal area stress InStress of the lesion.

[0084] Therefore, the quantitative elastic results of the internal area of ​​the lesion can be calculated according to this formula.

[0085] In one embodiment, in order to ensure that the acoustic radiation force of the first acoustic radiation force pulse on the first target position is the same as the acoustic radiation force of the second acoustic radiation force pulse on the second target position or is within a preset range, the value of the parameter of the first acoustic radiation force pulse can be set to be the same as the value of the parameter of the second acoustic radiation force pulse. In addition, the depth of the first target position in the external area of ​​the lesion is the same as the depth of the second target position in the internal area of ​​the lesion, thereby ensuring that the attenuation degree of the energy intensity of the sound field generated by the first acoustic radiation force pulse and the second acoustic radiation force pulse is the same.

[0086] For example, when the depth of the first target position in the external area of ​​the lesion is the same as the depth of the second target position in the internal area of ​​the lesion, the first acoustic radiation force pulse and the second acoustic radiation force pulse can be set to be consistent in parameter values ​​of parameters such as pulse length, pulse waveform, emission frequency, emission aperture or focusing intensity, so as to ensure that the acoustic radiation force generated by the first acoustic radiation force pulse on the first target position is the same or approximately the same as the acoustic radiation force generated by the second acoustic radiation force pulse on the second target position.

[0087] In addition, another way to ensure that the acoustic radiation force generated by the first acoustic radiation force pulse is the same or approximately the same as the acoustic radiation force generated by the second acoustic radiation force pulse may be to emit a first acoustic radiation force pulse having a parameter value of a first target value to the outer region of the lesion; determine a second target value corresponding to the first target value according to the depth of the first target position in the outer region of the lesion and the depth of the second target position in the inner region of the lesion, and emit a second acoustic radiation force pulse having a parameter value of the second target value to the inner region of the lesion. That is, after determining the parameter value of the first acoustic radiation force pulse, the parameter value of the second acoustic radiation force pulse may be adjusted according to the depth difference between the position where the first acoustic radiation force pulse acts and the position where the second acoustic radiation force pulse acts, so that the acoustic radiation force generated by the first acoustic radiation force pulse is the same or approximately the same as the acoustic radiation force generated by the second acoustic radiation force pulse.

[0088] For example, if the depth of the second target position in the internal area of ​​the lesion is greater than the depth of the first target position in the external area of ​​the lesion, when emitting the second acoustic radiation force pulse, the emission frequency of the second acoustic radiation force pulse can be adjusted to be lower than that of the first acoustic radiation force pulse; or, the pulse length of the second acoustic radiation force pulse can be adjusted to be higher, or the number of array elements emitting the second acoustic radiation force pulse in the ultrasound probe can be increased to improve its signal strength, etc. Therefore, the parameter value of the second acoustic radiation force pulse can be adjusted to improve its signal strength, so as to avoid excessive attenuation of the sound field energy intensity due to excessive depth, thereby ensuring that the acoustic radiation forces generated by the two acoustic radiation force pulses are the same or approximately the same.

[0089] In this embodiment, the quantitative elastic result of the internal area of ​​the lesion can be the quantitative elastic result of a single position in the internal area of ​​the lesion, or the quantitative elastic result of multiple positions in the internal area of ​​the lesion. Therefore, the ultrasonic imaging device can emit a second acoustic radiation force pulse to one or more target positions in the internal area of ​​the lesion to induce displacement or strain of the tissue corresponding to the one or more target positions. In addition, the second ultrasonic wave at different times is emitted to the one or more target positions in the internal area of ​​the lesion to detect the displacement change or strain change of the tissue corresponding to the target position, and the echo of the second ultrasonic wave at different times of the one or more target positions is received to obtain a second ultrasonic echo signal, and based on the second ultrasonic echo signal of the one or more target positions, the second strain elastic result of the one or more target positions is obtained.

[0090] After obtaining the second strain elastic result of one or more target positions in the internal area of ​​the lesion, the quantitative elastic result of the one or more target positions in the internal area of ​​the lesion can be determined based on the first strain elastic result, the first shear wave elastic result and the second strain elastic result of the one or more target positions in the internal area of ​​the lesion.

[0091] Specifically, since the range of the acoustic radiation force generated by the acoustic radiation force pulse focal area is limited (usually less than 0.5mm*0.5mm), when the lesion area is small, a set of second acoustic radiation force pulses can be emitted only in the internal area of ​​the lesion or its center to obtain a strain result in the internal area of ​​the lesion. This method can save detection time and reduce the amount of calculation. When the lesion area is large and the hardness is uneven, the second acoustic radiation force pulse can be emitted in sequence at each different position in the horizontal or vertical direction of the internal area of ​​the lesion according to the size of the lesion area, and the strain results of multiple different local positions can be obtained, and then the quantitative elastic result of each local position can be calculated based on the strain result of each local position.

[0092] After obtaining the quantitative elastic results of multiple target positions in the internal area of ​​the lesion, the ultrasonic imaging device can also perform statistics on the quantitative elastic results of multiple target positions in the internal area of ​​the lesion and display the statistical results, which include one or more of the median, mean, maximum value, minimum value, and standard deviation.

[0093] In a preferred implementation of this embodiment, when displaying the ultrasound image and the quantitative elasticity result, the ultrasound image may be displayed, and the quantitative elasticity results of multiple target positions in the internal area of ​​the lesion may be mapped into a quantitative elasticity image of a target display effect, and the quantitative elasticity image of the target display effect may be displayed. The target display effect may include any one or more display effects of grayscale, pseudo color, and color.

[0094] In this embodiment, the target tissue may be liver tissue, and the external area of ​​the lesion includes a diffuse lesion area outside the lesion of the liver tissue or a non-lesion area outside the lesion, and the internal area of ​​the lesion includes a focal lesion area inside the lesion of the liver tissue.

[0095] In a preferred implementation of the present embodiment, the first shear wave elastic result includes the propagation velocity, Young's modulus or shear modulus of the first shear wave. When the first shear wave elastic result is the propagation velocity of the first shear wave, one calculation method may be to determine the time duration for the first shear wave to propagate from the wave source position to the first reference position based on the first ultrasonic echo signal at the first reference position in the external region of the lesion, and determine the propagation velocity of the first shear wave in the external region of the lesion according to the distance between the wave source position of the first shear wave and the first reference position and the time duration.

[0096] Among them, the time length of the first shear wave propagating from the wave source position to the first reference position, that is, the time length from the time when the first shear wave is generated to the time when the first shear wave propagates to the first reference position, the time when the first shear wave is generated can be the time when the ultrasonic imaging device emits the first acoustic radiation force pulse to the external area of ​​the lesion.

[0097] For example, Figure 4As shown, other areas outside the area surrounded by dotted lines in the target tissue are the external areas of the lesion. When calculating the shear wave elasticity results of the external area of ​​the lesion, it is assumed that point A is the point where the ultrasonic imaging device emits the first acoustic radiation force pulse, that is, the first acoustic radiation force pulse generates a shear wave at point A, and point A is the location of the shear wave source. After the shear wave is generated at point A, the shear wave can propagate to both sides and pass through point B. The ultrasonic imaging device then emits a series of ultrasonic waves to point B to track the shear wave propagating in the external area of ​​the lesion, and receives the echo signal of the ultrasonic wave, and then determines the time t for the shear wave to propagate from point A to point B based on the echo signal of the ultrasonic wave, and calculates the propagation speed of the shear wave based on the distance l between point A and point B and the time t, that is, the propagation speed of the shear wave when passing through point B is Vs=l / t.

[0098] In addition, another way to calculate the shear wave propagation velocity is to determine the time interval between the propagation of the first shear wave to the first reference position and the propagation to the second reference position based on the first ultrasonic echo signal at the first reference position in the external area of ​​the lesion and the first ultrasonic echo signal at the second reference position in the external area of ​​the lesion; and determine the propagation velocity of the first shear wave in the external area of ​​the lesion based on the distance between the first reference position and the second reference position and the time interval.

[0099] Still Figure 4 For example, after the shear wave is generated at point A, the shear wave can propagate to both sides, passing through points B and C. The ultrasonic imaging device transmits a series of ultrasonic waves to points B and C in turn to track the shear wave propagating in the external area of ​​the lesion, and receives the echo signal of the ultrasonic wave at point B and the echo signal of the ultrasonic wave at point C. The time it takes for the shear wave to propagate to point B is determined based on the echo signal of the ultrasonic wave at point B, and the time it takes for the shear wave to propagate to point C is determined based on the echo signal of the ultrasonic wave at point C. The duration t between the two times is determined, and the propagation speed of the shear wave is calculated based on the distance l between points B and C and the duration t, that is, the propagation speed of the shear wave Vs = l / t.

[0100] In the two methods of calculating the shear wave propagation velocity mentioned above, determining whether the shear wave propagates to the first reference position or the shear wave propagates to the second reference position can be based on the tissue displacement / tissue velocity curve of the reference position to find the time when the shear wave propagates to the reference position. For example, when the tissue displacement of the reference position reaches a peak value, it is considered that the shear wave has just arrived at the reference position.

[0101] After obtaining the propagation velocity of the shear wave, according to Young's modulus E = 3*ρVs 2 , or shear modulus G = ρVs 2The formulas can be used to further calculate various physical quantities reflecting tissue hardness, where ρ is tissue density. The greater the shear wave propagation velocity Vs, or the greater the Young's modulus E, or the greater the shear modulus G, the higher the tissue hardness.

[0102] Therefore, the first shear wave elastic result may include the propagation velocity of the first shear wave, or the first Young's modulus converted from the propagation velocity of the first shear wave, or the first shear modulus converted from the propagation velocity of the first shear wave, and the quantitative elastic result may include the propagation velocity of the second shear wave propagating in the internal area of ​​the lesion, or the second Young's modulus converted from the propagation velocity of the second shear wave, or the second shear modulus converted from the propagation velocity of the second shear wave.

[0103] In another preferred implementation of this embodiment, the ultrasonic imaging device can display an ultrasonic image, as well as a first strain elasticity result, a first shear wave elasticity result, and a second strain elasticity result, as well as a quantitative elasticity result, so that the user can compare the hardness between the external area and the internal area of ​​the lesion, and can also compare the difference between the hardness of the internal area of ​​the lesion reflected by the strain elasticity measurement results and the hardness reflected by the quantitative elasticity results.

[0104] Alternatively, the ultrasound imaging device displays the ultrasound image, and displays the first shear wave elasticity result and the quantitative elasticity result, so that the user can compare the hardness between the outer area and the inner area of ​​the lesion. Alternatively, in addition to displaying the ultrasound image, the first shear wave elasticity result and the quantitative elasticity result, the comparison result of the first shear wave elasticity result and the quantitative elasticity result can also be displayed, and the user can directly determine the hardness difference between the outer area and the inner area of ​​the lesion through the comparison result.

[0105] The comparison result may be the difference or ratio between the first shear wave elasticity result and the quantitative elasticity result, so that the user can know the difference in tissue elasticity or tissue hardness between the internal area of ​​the lesion and the external area of ​​the lesion through the comparison result.

[0106] In a preferred implementation of the present embodiment, the external area of ​​the lesion of the target tissue is determined based on the ultrasound image, and the method may be to determine the position of a first region of interest of the ultrasound image, and use the first region of interest as the external area of ​​the lesion, and mark the first region of interest on the ultrasound image with a first marking style according to the position of the first region of interest, wherein the first region of interest includes a diffuse lesion area or a non-lesion area.

[0107] When determining the internal area of ​​the lesion of the target tissue according to the ultrasound image, the position of the second region of interest of the ultrasound image can be determined, the second region of interest is used as the internal area of ​​the lesion, and the second region of interest is marked in the ultrasound image with a second marking pattern different from the first marking pattern according to the position of the second region of interest. The second region of interest includes a focal lesion area, and the depth of the diffuse lesion area or the non-lesion area relative to the body surface is less than the depth of the focal lesion area relative to the body surface.

[0108] Since the signal transmission and reception processing operations for the internal area of ​​the lesion and the external area of ​​the lesion are different, it is necessary to identify the internal area of ​​the lesion and the external area of ​​the lesion in order to perform different processing operations. Prior to this, the target tissue of the subject can be ultrasonically scanned under the user's ultrasonic scanning operation to obtain an ultrasonic image, which can be a B-type ultrasonic image, a D-type ultrasonic image, or an M-type ultrasonic image. After obtaining the ultrasonic image, the ultrasonic imaging device can determine the region of interest in the ultrasonic image that contains the focal lesion area, and use the region of interest as the internal area of ​​the lesion, and can mark its position. Figure 5 As shown, after obtaining the ultrasound image, the region of interest is determined as a closed area containing the lesion, and it is used as the internal area of ​​the lesion, and the position of the region is shown in a rectangular frame (such as the rectangular frame indicated by the arrow). Of course, the region of interest can also be shown in a circular, elliptical or lesion boundary line frame drawn by the user according to the two-dimensional image. After determining the internal area of ​​the lesion, the other area outside the closed area where the area is located is the external area of ​​the lesion, and different processing operations can be performed on the internal area of ​​the lesion and the external area of ​​the lesion respectively.

[0109] exist Figure 5 In the example shown, after marking the rectangular frame corresponding to the internal area of ​​the lesion, the region of interest containing the diffuse lesion area or the non-lesion area in the ultrasound image can be further determined, and the region of interest is used as the external area of ​​the lesion, and the position of the external area of ​​the lesion is marked on the ultrasound image, that is, Figure 6 The closed area framed by the rectangular box on the right side of the image. The rectangular box on the right side may be different from the rectangular box on the left side in marking style, such as the border of the rectangular box on the left side and the border of the rectangular box on the right side may be displayed in different colors, or in different line shapes (such as solid lines and dotted lines), or in lines of different thicknesses, etc. Therefore, the user can distinguish the internal area and the external area of ​​the lesion in the ultrasound image through the rectangular boxes of different marking styles.

[0110] In a preferred implementation of this embodiment, when calculating the quantitative elastic result of the internal area of ​​the lesion, the stress result can be determined according to the first strain elastic result and the first shear wave elastic result, and the quantitative elastic result corresponding to the second strain elastic result can be determined according to the stress result.

[0111] For example, the formula OutStrain*OutE=Instrain(i)*InE(i) has been mentioned above, where the product of the first strain elastic result OutStrain and the first shear wave elastic result OutE is the stress on the external area of ​​the lesion, and the quantitative elastic result InE(i) of the internal area of ​​the lesion is OutStrain*OutE / Instrain(i).

[0112] In this embodiment, the first ultrasonic wave used to detect the displacement change or strain change of the tissue in the external area of ​​the lesion and the first shear wave propagating in the external area of ​​the lesion may include multiple groups of ultrasonic waves, wherein the first ultrasonic echo signal corresponding to one group of ultrasonic waves can be used to process to obtain the first strain elastic result, and the first ultrasonic echo signal corresponding to another group of ultrasonic waves can be used to process to obtain the first shear wave elastic result, that is, the first shear wave elastic result and the first strain elastic result of the external area of ​​the lesion are obtained by processing based on the ultrasonic echo signals of different groups of ultrasonic waves.

[0113] In addition, the first shear wave elasticity result and the first strain elasticity result of the external area of ​​the lesion can also be obtained by processing the ultrasonic echo signal based on the same set of ultrasonic waves. That is, the first ultrasonic wave includes a group of ultrasonic waves, the first strain elasticity result is obtained by processing the first ultrasonic echo signal corresponding to the group of ultrasonic waves, and the first shear wave elasticity result is also obtained by processing the first ultrasonic echo signal corresponding to the group of ultrasonic waves.

[0114] In this embodiment, the second acoustic radiation force pulse emitted to the internal area of ​​the lesion will also generate a second shear wave propagating in the internal area of ​​the lesion. Therefore, the shear wave elastic result of the internal area of ​​the lesion can be calculated based on the second shear wave. That is, the ultrasonic imaging device emits a third ultrasonic wave to the internal area of ​​the lesion to track the second shear wave propagating in the internal area of ​​the lesion, and receives the echo of the third ultrasonic wave to obtain a third ultrasonic echo signal, and the second shear wave elastic result of the internal area of ​​the lesion is obtained based on the third ultrasonic echo signal.

[0115] After obtaining the second shear wave elasticity result of the internal area of ​​the lesion, the ultrasonic imaging device can also compare and display the second shear wave elasticity result and the above-mentioned quantitative elasticity result, so that the user can compare the difference between the result obtained by the conventional shear wave elasticity measurement method and the quantitative elasticity result obtained by the above-mentioned quantitative calculation.

[0116] Alternatively, the final elastic result is determined based on the second shear wave elastic result and the quantitative elastic result. For example, a weighted sum of the second shear wave elastic result and the quantitative elastic result may be calculated, and the respective weights may be preset by the user, and the weighted sum is used as the final elastic result of the internal area of ​​the lesion, and the final elastic result is displayed at a position corresponding to the second shear wave elastic result.

[0117] Therefore, in this embodiment and its preferred embodiments, the quantitative elasticity result of the internal area of ​​the lesion can be calculated based on the shear wave elasticity result and strain elasticity result of the external area of ​​the lesion and the strain elasticity result of the internal area outside the lesion, and the quantitative elasticity result is a specific numerical value, so that the elasticity and hardness of the tissue inside the lesion can be quantitatively determined. In addition, since the shear wave elasticity result and strain elasticity result of the external area of ​​the lesion and the strain elasticity result of the internal area outside the lesion are accurate and reliable, compared with directly measuring the shear wave elasticity of the internal area of ​​the lesion, the quantitative elasticity result of the internal area of ​​the lesion calculated by this embodiment is more accurate, and can better describe the morphology and boundaries of the lesion.

[0118] Based on Figure 2 The invention concept of the embodiment shown in the figure is the same. The embodiment of the present application also proposes another embodiment of the ultrasonic elastic imaging method. Figure 7 Another embodiment of the ultrasound elastic imaging method in the embodiment of the present application includes:

[0119] 701. Acquire an ultrasound image of a target tissue, where the ultrasound image includes a first region of interest and a second region of interest of the target tissue;

[0120] The ultrasonic imaging device can perform ultrasonic scanning on the target tissue of the subject under the operation of the user to obtain an ultrasonic image of the target tissue. The first region of interest and the second region of interest of the target tissue in the ultrasonic image can be automatically determined by the ultrasonic imaging device, or the user can input a setting operation for the region of interest. The ultrasonic imaging device determines the first region of interest and the second region of interest according to the setting operation of the user. This embodiment does not limit the way in which the ultrasonic imaging device determines the above regions of interest.

[0121] The target tissue may be any organ tissue of the subject, for example, liver tissue. The subject may be a human body or various animals. When the target tissue is liver tissue, the first region of interest includes the diffuse lesion area outside the lesion of the liver tissue or the non-lesion area outside the lesion, and the second region of interest includes the focal lesion area inside the lesion of the liver tissue. The focal lesion area inside the lesion limits the propagation of the shear wave, resulting in inaccurate results obtained by conventional shear wave elasticity measurement; while the diffuse lesion area outside the lesion or the non-lesion area outside the lesion has little effect on the penetration of the shear wave, so the results obtained by conventional shear wave elasticity measurement are relatively accurate.

[0122] 702. Inducing displacement or strain in tissues corresponding to the first region of interest and the second region of interest;

[0123] The ultrasonic imaging device induces displacement or strain of tissues corresponding to the first region of interest and the second region of interest by emitting ultrasonic waves to the tissues corresponding to the first region of interest and the second region of interest, and the ultrasonic waves cause the tissues to vibrate, thereby inducing displacement or strain of the tissues.

[0124] 703. Transmitting first ultrasonic waves at different times to the first region of interest and the second region of interest to detect the displacement change or the strain change of the tissues corresponding to the first region of interest and the second region of interest, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals;

[0125] 704. Obtain a first strain elasticity result of the first region of interest and a second strain elasticity result of the second region of interest based on the first ultrasonic echo signal;

[0126] While causing the tissues corresponding to the first region of interest and the second region of interest to generate displacement or strain, the ultrasonic imaging device also transmits first ultrasonic waves at different times to the first region of interest and the second region of interest to detect the change in displacement or strain of the tissues corresponding to the first region of interest and the second region of interest. And, based on the first ultrasonic echo signals corresponding to the first ultrasonic waves at different times, a first strain elasticity result of the first region of interest and a second strain elasticity result of the second region of interest are obtained.

[0127] 705. Generate a first shear wave that propagates in the first region of interest;

[0128] 706. Transmit a second ultrasonic wave to the first region of interest to track the first shear wave propagating in the first region of interest, and receive an echo of the second ultrasonic wave to obtain a second ultrasonic echo signal;

[0129] 707. Obtain a first shear wave elasticity result of the first region of interest based on the second ultrasonic echo signal;

[0130] The ultrasonic imaging device also generates a first shear wave propagating in the first region of interest, and transmits a second ultrasonic wave for tracking the first shear wave, and obtains the first shear wave elasticity result of the first region of interest based on a second ultrasonic echo signal corresponding to the second ultrasonic wave.

[0131] 708. Determine a quantitative elastic result of the second region of interest based on the first strain elastic result, the second strain elastic result, and the first shear wave elastic result;

[0132] 709. Displaying the ultrasound image and the quantitative elasticity result;

[0133] The ultrasonic imaging device determines the quantitative elastic result of the second region of interest based on the first strain elastic result, the second strain elastic result and the first shear wave elastic result, and displays the ultrasonic image and the quantitative elastic result of the second region of interest.

[0134] In this embodiment, the ultrasonic imaging device can obtain the first shear wave elasticity result and the first strain elasticity result of the first region of interest in the target tissue of the subject, and obtain the second strain elasticity result of the second region of interest in the target tissue, and determine the quantitative elasticity result of the second region of interest based on the first shear wave elasticity result, the first strain elasticity result and the second strain elasticity result. Since the shear wave elasticity result and the strain elasticity result of the first region of interest and the strain elasticity result of the second region of interest are accurate, the quantitative elasticity result of the second region of interest calculated based on the above results is more accurate than the result obtained by directly measuring the shear wave elasticity of the second region of interest, and can also more accurately present the morphology and boundaries of the lesion.

[0135] In one implementation of this embodiment, the target tissue may be one or more, and the tissues corresponding to the first region of interest and the second region of interest may be different regions of the same target tissue, or the tissues corresponding to the first region of interest and the second region of interest may be different target tissues.

[0136] For example, the first region of interest may be a diffuse lesion region outside the lesion of liver tissue or a non-lesion region outside the lesion, and the second region of interest may be a focal lesion region inside the lesion of liver tissue. Alternatively, the first region of interest may be a diffuse lesion region outside the lesion of spleen tissue or a non-lesion region outside the lesion, and the second region of interest may be a focal lesion region inside the lesion of liver tissue.

[0137] Since the deeper the position in the tissue relative to the body surface, the less favorable it is for the propagation of shear waves, the shear wave elasticity result of the position obtained by conventional shear wave elasticity measurement is not accurate. For this reason, in another implementation of this embodiment, the depth of the tissue area corresponding to the first region of interest relative to the body surface is less than the depth of the tissue area corresponding to the second region of interest relative to the body surface, and the quantitative elasticity result of the second region of interest can be calculated based on the method of this embodiment, which is more accurate than the result obtained by measuring the deeper second region of interest by conventional shear wave elasticity measurement method.

[0138] In addition, the greater the hardness of the tissue, the less favorable it is for the propagation of shear waves. Therefore, the harder the tissue, the less accurate the result obtained by conventional shear wave elasticity measurement. To this end, in another embodiment of this embodiment, the hardness of the tissue area corresponding to the first region of interest is less than the hardness of the tissue area corresponding to the second region of interest. The quantitative elasticity result of the second region of interest can be calculated based on the method of this embodiment. This result is more accurate than the result obtained by measuring the second region of interest with greater hardness by conventional shear wave elasticity measurement.

[0139] In another embodiment of the present embodiment, the driving force corresponding to the displacement or strain of the tissues corresponding to the first region of interest and the second region of interest is the same. The driving force may be an acoustic radiation force, which may be generated by emitting an acoustic radiation force pulse to the first region of interest or the second region of interest. In other words, the acoustic radiation force generated by emitting an acoustic radiation force pulse to the first region of interest is the same as the acoustic radiation force generated by emitting an acoustic radiation force pulse to the second region of interest. In addition, emitting an acoustic radiation force pulse to the first region of interest may also generate the first shear wave propagating in the first region of interest, and then the first shear wave elastic result of the first region of interest may be obtained based on the first shear wave.

[0140] Based on this, according to the stress formula Stress = Strain * E, when the stress is the same or approximately the same, that is, the stress OutStress of the first region of interest is equal to the stress InStress of the second region of interest, then according to the formula Stress = Strain * E, we can get:

[0141] OutStrain*OutE=Instrain(i)*InE(i);

[0142] Among them, OutStrain refers to the first strain elastic result, OutE refers to the first shear wave elastic result, OutStrain*OutE is the stress of the first area of ​​interest OutStress; Instrain(i) refers to the second strain elastic result, InE(i) refers to the quantitative elastic result, Instrain(i)*InE(i) is the stress of the second area of ​​interest InStress.

[0143] Therefore, according to the above principle, the quantitative elastic result of the second region of interest can be calculated.

[0144] In another implementation of this embodiment, when displaying the ultrasound image and the quantitative elasticity result, the ultrasound image may be displayed, and the quantitative elasticity result of the second region of interest may be mapped to a quantitative elasticity image of a target display effect, and the quantitative elasticity image of the target display effect may be displayed. The target display effect includes any one or more display effects of grayscale, pseudo color, and color.

[0145] In another implementation of this embodiment, the ultrasonic imaging device can display an ultrasonic image, as well as a first strain elasticity result, a first shear wave elasticity result, and a second strain elasticity result, and display a quantitative elasticity result, so that the user can compare the hardness between the first region of interest and the second region of interest, and can also compare the difference between the hardness reflected by the strain elasticity measurement results and the hardness reflected by the quantitative elasticity results in the second region of interest.

[0146] Alternatively, the ultrasonic imaging device displays the ultrasonic image, and displays the first shear wave elasticity result and the quantitative elasticity result, so that the user can compare the hardness difference between the first region of interest and the second region of interest. Alternatively, in addition to displaying the ultrasonic image, the first shear wave elasticity result and the quantitative elasticity result, the comparison result of the first shear wave elasticity result and the quantitative elasticity result can also be displayed, and the user can directly determine the hardness difference between the first region of interest and the second region of interest through the comparison result.

[0147] The comparison result may be the difference or ratio between the first shear wave elasticity result and the quantitative elasticity result, so that the user can know the difference in tissue elasticity or tissue hardness between the first region of interest and the second region of interest through the comparison result.

[0148] In another implementation of this embodiment, the ultrasonic imaging device may mark the first region of interest on the ultrasonic image with a first marking style according to the location of the first region of interest, and mark the second region of interest on the ultrasonic image with a second marking style according to the location of the second region of interest, wherein the first marking style is different from the second marking style.

[0149] The first marking style or the second marking style can be any closed graphic, such as a rectangular frame or a circular, elliptical, or lesion boundary line frame drawn by the user based on the two-dimensional image to show the region of interest. Different marking styles can be different colors for the frame, or different line shapes (such as solid lines and dotted lines), or lines of different thicknesses, etc. Therefore, the user can distinguish the first region of interest and the second region of interest in the ultrasound image through graphics of different marking styles.

[0150] In another implementation of this embodiment, when calculating the quantitative elastic result of the second region of interest, a stress result may be determined according to the first strain elastic result and the first shear wave elastic result, and a quantitative elastic result corresponding to the second strain elastic result may be determined according to the stress result.

[0151] For example, the formula OutStrain*OutE=Instrain(i)*InE(i) has been mentioned above, where the product of the first strain elastic result OutStrain and the first shear wave elastic result OutE is the stress on the external area of ​​the lesion, and the quantitative elastic result of the second region of interest InE(i)=OutStrain*OutE / Instrain(i).

[0152] In this embodiment, the acoustic radiation force pulse emitted to the second region of interest will also generate a second shear wave propagating in the second region of interest. Therefore, the shear wave elastic result of the second region of interest can be calculated based on the second shear wave. That is, the ultrasonic imaging device emits a third ultrasonic wave to the second region of interest to track the second shear wave propagating in the second region of interest, and receives the echo of the third ultrasonic wave to obtain a third ultrasonic echo signal, and the second shear wave elastic result of the second region of interest is obtained based on the third ultrasonic echo signal.

[0153] After obtaining the second shear wave elasticity result of the second region of interest, the ultrasonic imaging device can also compare and display the second shear wave elasticity result and the above-mentioned quantitative elasticity result, so that the user can compare the difference between the result obtained by the conventional shear wave elasticity measurement method and the quantitative elasticity result obtained by the above-mentioned quantitative calculation.

[0154] Alternatively, the final elastic result is determined based on the second shear wave elastic result and the quantitative elastic result. For example, a weighted sum of the second shear wave elastic result and the quantitative elastic result may be calculated, and the respective weights may be preset by the user, and the weighted sum is used as the final elastic result of the second region of interest, and the final elastic result is displayed at a position corresponding to the second shear wave elastic result.

[0155] Based on the above Figure 1The specific structural composition of the ultrasonic imaging device and the functions of each structure shown further describe in detail the components of the ultrasonic imaging device and the functions and operations performed by each component.

[0156] In this embodiment, the ultrasonic imaging device includes:

[0157] Ultrasound probe;

[0158] A transmitting circuit, used for stimulating the ultrasonic probe to transmit ultrasonic waves to a target tissue of a subject;

[0159] A receiving circuit, used for controlling the ultrasonic probe to receive the echo of the ultrasonic wave returned by the target tissue to obtain an ultrasonic echo signal;

[0160] A processor is used to process the ultrasonic echo signal to obtain an ultrasonic image of the target tissue, and perform the above-mentioned Figure 2 or Figure 7 The ultrasonic elasticity imaging method performed by the ultrasonic imaging device in the illustrated embodiment and its multiple preferred implementations.

[0161] The functions and operations performed by the components of the ultrasonic imaging device in this embodiment are similar to those described above. Figure 2 or Figure 7 The operations performed by the ultrasonic imaging device in the illustrated embodiment and its multiple preferred implementations are similar and will not be described in detail here.

[0162] In this embodiment, the ultrasonic imaging device can obtain the first shear wave elastic result and the first strain elastic result of the external area of ​​the lesion in the target tissue of the subject, and obtain the second strain elastic result of the internal area of ​​the lesion in the target tissue, and determine the quantitative elastic result of the internal area of ​​the lesion based on the first shear wave elastic result, the first strain elastic result and the second strain elastic result. Since the shear wave elastic result and the strain elastic result of the external area of ​​the lesion and the strain elastic result of the internal area of ​​the lesion are accurate, the quantitative elastic result of the internal area of ​​the lesion calculated according to the above results is more accurate than the result obtained by directly measuring the shear wave elasticity of the internal area of ​​the lesion, and the morphology and boundary of the lesion can also be more accurately presented.

[0163] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0164] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0165] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0166] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0167] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, read-only memory), random access memory (RAM, random access memory), disk or optical disk and other media that can store program code.

Claims

1. An ultrasonic elastic imaging method, characterized in that: include: Acquire an ultrasonic image of a target tissue, and determine an internal region of a lesion of the target tissue and an external region of the lesion according to the ultrasonic image; emitting a first acoustic radiation force pulse to an outer region of the lesion to induce displacement or strain of tissue corresponding to the outer region of the lesion and generate a first shear wave propagating in the outer region of the lesion; Transmitting first ultrasonic waves at different times to the external area of ​​the lesion to detect the change in displacement or strain of the tissue corresponding to the external area of ​​the lesion and to track the first shear wave propagating in the external area of ​​the lesion, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals; Based on the first ultrasonic echo signal, obtaining a first strain elasticity result of the outer area of ​​the lesion; and based on the first ultrasonic echo signal, obtaining a first shear wave elasticity result of the outer area of ​​the lesion; emitting a second acoustic radiation force pulse to the inner region of the lesion to induce displacement or strain of tissue corresponding to the inner region of the lesion; Transmitting second ultrasonic waves at different times to the internal area of ​​the lesion to detect the change in displacement or the change in strain of the tissue corresponding to the internal area of ​​the lesion, and receiving echoes of the second ultrasonic waves at different times to obtain second ultrasonic echo signals; Based on the second ultrasonic echo signal, obtaining a second strain elasticity result of the internal area of ​​the lesion; determining a quantitative elastic result of an inner region of the lesion based on the first strain elastic result, the first shear wave elastic result, and the second strain elastic result; The ultrasound image and the quantitative elasticity results are displayed.

2. The method according to claim 1, characterized in that The acoustic radiation force generated by the first acoustic radiation force pulse on a first target position in the outer region of the lesion is the same as the acoustic radiation force generated by the second acoustic radiation force pulse on a second target position in the inner region of the lesion, or the difference between the two is within a preset range; The first target position is a position corresponding to the first strain elasticity result, and the second target position is a position corresponding to the second strain elasticity result.

3. The method according to claim 2, characterized in that The value of the parameter of the first acoustic radiation force pulse is the same as the value of the parameter of the second acoustic radiation force pulse, and the depth of the first target position in the outer region of the lesion is the same as the depth of the second target position in the inner region of the lesion.

4. The method according to claim 2, characterized in that: The emitting a first acoustic radiation force pulse to an outer area of ​​the lesion comprises: emitting the first acoustic radiation force pulse having a parameter value equal to a first target value to an outer area of ​​the lesion; The emitting a second acoustic radiation force pulse toward the inner area of ​​the lesion comprises: emitting the second acoustic radiation force pulse having a parameter value equal to a second target value to an inner area of ​​the lesion; The second target value is determined according to the depth of the first target position in the outer area of ​​the lesion, the depth of the second target position in the inner area of ​​the lesion, and the first target value.

5. The method according to claim 3 or 4, characterized in that: The parameters of the first acoustic radiation force pulse and / or the parameters of the second acoustic radiation force pulse include at least one of pulse length, pulse waveform, emission frequency, emission aperture and focusing intensity.

6. The method according to claim 1, characterized in that The emitting a second acoustic radiation force pulse toward the inner area of ​​the lesion comprises: transmitting the second acoustic radiation force pulse to one or more target positions in the internal area of ​​the lesion to induce displacement or strain of tissues corresponding to the one or more target positions; The step of emitting a second ultrasonic wave at different times to the internal area of ​​the lesion comprises: Transmitting second ultrasonic waves at different times to the one or more target positions in the internal area of ​​the lesion to detect the change in displacement or the change in strain of the tissue corresponding to the one or more target positions, and receiving echoes of the second ultrasonic waves at different times of the one or more target positions to obtain the second ultrasonic echo signals; The step of obtaining a second strain elasticity result of the internal area of ​​the lesion based on the second ultrasonic echo signal comprises: Based on the second ultrasonic echo signals of the one or more target positions, the second strain elasticity results of the one or more target positions are obtained.

7. The method according to claim 6, characterized in that The step of determining the quantitative elastic result of the internal area of ​​the lesion based on the first strain elastic result, the first shear wave elastic result and the second strain elastic result comprises: The quantitative elastic result of one or more target positions in the inner region of the lesion is determined based on the first strain elastic result, the first shear wave elastic result and the second strain elastic result of one or more target positions in the inner region of the lesion.

8. The method according to claim 7, characterized in that After obtaining the quantitative elastic results of a plurality of target locations in the inner region of the lesion, the method further comprises: The quantitative elastic results of the plurality of target positions in the internal area of ​​the lesion are statistically analyzed and the statistical results are displayed, wherein the statistical results include one or more of a median, a mean, a maximum value, a minimum value, and a standard deviation.

9. The method according to claim 7, characterized in that: The displaying of the ultrasound image and the quantitative elasticity result comprises: The ultrasound image is displayed, the quantitative elasticity results of multiple target positions in the internal area of ​​the lesion are mapped into a quantitative elasticity image of a target display effect, and the quantitative elasticity image of the target display effect is displayed; the target display effect includes any one or more display effects of grayscale, pseudo color, and color.

10. The method according to any one of claims 1 to 9, characterized in that: The target tissue includes liver tissue, the external area of ​​the lesion includes a diffuse lesion area outside the lesion of the liver tissue or a non-lesion area outside the lesion, and the internal area of ​​the lesion includes a focal lesion area inside the lesion of the liver tissue.

11. The method according to any one of claims 1 to 9, characterized in that: The first shear wave elastic result includes a propagation velocity of the first shear wave, a first Young's modulus or a first shear modulus, and the quantitative elastic result includes a propagation velocity of the second shear wave, a second Young's modulus or a second shear modulus.

12. The method according to any one of claims 1 to 9, characterized in that: The step of obtaining a first shear wave elasticity result of an external area of ​​the lesion based on the first ultrasonic echo signal comprises: determining the time length of the first shear wave propagating from the wave source position to the first reference position based on the first ultrasound echo signal at the first reference position in the external area of ​​the lesion; determining a propagation speed of the first shear wave in an area outside the lesion according to a distance between a wave source position of the first shear wave and the first reference position and the duration; Alternatively, obtaining a first shear wave elasticity result of an external area of ​​the lesion based on the first ultrasonic echo signal includes: Determine the time interval between the propagation of the first shear wave to the first reference position and the propagation to the second reference position based on the first ultrasonic echo signal at the first reference position in the external area of ​​the lesion and the first ultrasonic echo signal at the second reference position in the external area of ​​the lesion; The propagation speed of the first shear wave in the outer region of the lesion is determined according to the distance between the first reference position and the second reference position and the duration of the interval.

13. The method according to any one of claims 1 to 9, characterized in that: The method further comprises: displaying the first strain elastic result, the first shear wave elastic result, and the second strain elastic result; or, displaying the first shear wave elastic result; or, The first shear wave elastic result is displayed, and a comparison result between the first shear wave elastic result and the quantitative elastic result is displayed.

14. The method according to any one of claims 1 to 9, characterized in that: Determining the external area of ​​the lesion of the target tissue according to the ultrasound image comprises: Determine the position of a first region of interest of the ultrasound image, take the first region of interest as the external region of the lesion, and mark the first region of interest on the ultrasound image with a first marking style according to the position of the first region of interest, wherein the first region of interest includes a diffuse lesion area or a non-lesion area.

15. The method according to claim 14, characterized in that The step of determining the internal area of ​​the lesion of the target tissue according to the ultrasound image comprises: Determine the position of a second region of interest of the ultrasound image, take the second region of interest as the internal region of the lesion, and mark the second region of interest on the ultrasound image with a second marking style different from the first marking style according to the position of the second region of interest, wherein the second region of interest includes a focal lesion area, and the depth of the diffuse lesion area or the non-lesion area relative to the body surface is less than the depth of the focal lesion area relative to the body surface.

16. The method according to any one of claims 1 to 9, characterized in that: The step of determining the quantitative elastic result of the internal area of ​​the lesion based on the first strain elastic result, the first shear wave elastic result and the second strain elastic result comprises: determining a first stress result according to the first strain elastic result and the first shear wave elastic result; The quantitative elastic result is determined based on the first stress result and the second strain elastic result.

17. The method according to any one of claims 1 to 9, characterized in that: The first ultrasonic wave includes multiple groups of ultrasonic waves, the first strain elasticity result is obtained based on the first ultrasonic echo signal corresponding to one group of ultrasonic waves, and the first shear wave elasticity result is obtained based on the first ultrasonic echo signal corresponding to another group of ultrasonic waves; or, The first ultrasonic wave includes a group of ultrasonic waves, the first strain elastic result is obtained based on the first ultrasonic echo signal processing corresponding to the group of ultrasonic waves, and the first shear wave elastic result is obtained based on the first ultrasonic echo signal processing corresponding to the group of ultrasonic waves.

18. The method according to any one of claims 1 to 9, characterized in that: The method further comprises: generating a second shear wave that propagates in an interior region of the lesion; Transmitting a third ultrasonic wave to the inner region of the lesion to track the second shear wave propagating in the inner region of the lesion, and receiving an echo of the third ultrasonic wave to obtain a third ultrasonic echo signal; Based on the third ultrasonic echo signal, obtaining a second shear wave elasticity result of the internal area of ​​the lesion; The second shear wave elastic result and the quantitative elastic result are compared and displayed, or a final elastic result is determined based on the second shear wave elastic result and the quantitative elastic result.

19. An ultrasonic elastic imaging method, characterized in that: include: Acquire an ultrasonic image of a target tissue, wherein the ultrasonic image includes a first region of interest and a second region of interest of the target tissue; Inducing displacement or strain in tissues corresponding to the first region of interest and the second region of interest; Transmitting first ultrasonic waves at different times to the first region of interest and the second region of interest to detect the displacement change or the strain change of the tissues corresponding to the first region of interest and the second region of interest, and receiving echoes of the first ultrasonic waves at different times to obtain first ultrasonic echo signals; Based on the first ultrasonic echo signal, obtaining a first strain elasticity result of the first region of interest and a second strain elasticity result of the second region of interest; generating a first shear wave that propagates in the first region of interest; Transmitting a second ultrasonic wave to the first region of interest to track the first shear wave propagating in the first region of interest, and receiving an echo of the second ultrasonic wave to obtain a second ultrasonic echo signal; obtaining a first shear wave elastic result of the first region of interest based on the second ultrasonic echo signal; determining a quantitative elastic result of the second region of interest based on the first strain elastic result, the second strain elastic result, and the first shear wave elastic result; The ultrasound image and the quantitative elasticity results are displayed.

20. The method according to claim 19, characterized in that The target organization includes one or more, The tissues corresponding to the first region of interest and the second region of interest are different regions of the same target tissue, or the tissues corresponding to the first region of interest and the second region of interest are different target tissues.

21. The method according to claim 20, characterized in that The depth of the tissue region corresponding to the first region of interest relative to the body surface is smaller than the depth of the tissue region corresponding to the second region of interest relative to the body surface; or the hardness of the tissue region corresponding to the first region of interest is smaller than the hardness of the tissue region corresponding to the second region of interest.

22. The method according to claim 19, characterized in that The driving forces that induce displacement or strain in tissues corresponding to the first region of interest and the second region of interest are the same.

23. The method according to claim 19, characterized in that The displaying of the ultrasound image and the quantitative elasticity result comprises: The ultrasound image is displayed, the quantitative elasticity result of the second region of interest is mapped into a quantitative elasticity image of a target display effect, and the quantitative elasticity image of the target display effect is displayed; the target display effect includes any one or more display effects of grayscale, pseudo color, and color.

24. The method according to any one of claims 19 to 23, characterized in that The target tissue includes liver tissue, the first region of interest includes a diffuse lesion area outside the lesion of the liver tissue or a non-lesion area outside the lesion, and the second region of interest includes a focal lesion area inside the lesion of the liver tissue.

25. The method according to any one of claims 19 to 23, characterized in that The method further comprises: displaying the first strain elastic result, the first shear wave elastic result, and the second strain elastic result; or, displaying the first shear wave elastic result; or, The first shear wave elastic result is displayed, and a comparison result between the first shear wave elastic result and the quantitative elastic result is displayed.

26. The method according to any one of claims 19 to 23, characterized in that The method further comprises: Marking the first region of interest on the ultrasound image in a first marking style according to the position of the first region of interest; Marking the second region of interest on the ultrasound image in a second marking style according to the position of the second region of interest; The first marking pattern is different from the second marking pattern.

27. The method according to any one of claims 19 to 23, characterized in that The step of determining the quantitative elastic result of the second region of interest based on the first strain elastic result, the second strain elastic result and the first shear wave elastic result comprises: determining a first stress result according to the first strain elastic result and the first shear wave elastic result; The quantitative elastic result is determined based on the first stress result and the second strain elastic result.

28. The method according to any one of claims 19 to 23, characterized in that The method further comprises: generating a second shear wave that propagates in the second region of interest; transmitting a third ultrasonic wave to the second region of interest to track the second shear wave propagating in the second region of interest, and receiving an echo of the third ultrasonic wave to obtain a third ultrasonic echo signal; Based on the third ultrasonic echo signal, obtaining a second shear wave elastic result of the second region of interest; The second shear wave elastic result and the quantitative elastic result are compared and displayed, or a final elastic result is determined based on the second shear wave elastic result and the quantitative elastic result.

29. An ultrasonic imaging device, characterized in that: include: Ultrasound probe; A transmitting circuit, used for stimulating the ultrasonic probe to transmit ultrasonic waves to a target tissue of a subject; A receiving circuit, used for controlling the ultrasonic probe to receive the echo of the ultrasonic wave returned by the target tissue to obtain an ultrasonic echo signal; A processor is used to process the ultrasonic echo signal to obtain an ultrasonic image of the target tissue, and to perform the ultrasonic elastic imaging method according to any one of claims 1 to 28 based on the ultrasonic image.

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