Three-dimensional real-time passive acoustic imaging method, device and equipment based on row-column addressing ultrasonic transducer and medium

Abstract

The invention provides a three-dimensional real-time passive acoustic imaging method, device and equipment based on a row-column addressing ultrasonic transducer and a medium. The method comprises the following steps: passively receiving an ultrasonic signal for monitoring microbubble acoustic cavitation activity in a three-dimensional manner through the row-column addressing ultrasonic transducer; the row-column addressing ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signals comprise row array signals and column array signals; respectively reconstructing a three-dimensional sound field according to the row array signal and the column array signal to obtain a row array three-dimensional sound field and a column array three-dimensional sound field; and selecting a target frequency band from the frequency bands, and performing cross-correlation superposition on the row array three-dimensional sound fields and the column array three-dimensional sound fields on the frequencies in the target frequency band to obtain a three-dimensional passive cavitation image of the row array and the column array. According to the invention, artifacts can be effectively reduced, and more accurate positioning and monitoring are realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of ultrasonic imaging, and in particular relates to a three-dimensional real-time passive acoustic imaging method, device, equipment and medium based on row-column addressing ultrasonic transducers. Background Art

[0002] A large number of clinical studies have shown that microbubble-mediated ultrasonic cavitation therapy can effectively assist drug delivery and improve the treatment of diseases such as liver cancer and pancreatic cancer. This adjuvant treatment method mainly mediates the desired biological effect through the mechanical effect generated by microbubble cavitation activity. However, the randomness of microbubble cavitation activity is relatively strong. In particular, under the same sound pressure, larger microbubbles are more likely to undergo transient cavitation and rupture, which may form high-energy jets on the surface of soft tissues and damage surrounding healthy tissues. In order to ensure the safety and effectiveness of microbubble-mediated ultrasonic cavitation in treatment, reduce the risk of damage to healthy tissues, and improve the accuracy of targeted drug delivery, real-time imaging, monitoring and regulation of the state and distribution of microbubbles in the body are crucial. At present, most passive acoustic imaging methods only provide two-dimensional cross-sectional cavitation activity information and cannot dynamically capture three-dimensional cavitation activity. The focal area of ​​the focused ultrasound beam is a three-dimensional ellipsoid shape, which is easy to induce cavitation activity outside the imaging plane and in non-target areas. Relying only on two-dimensional imaging will ignore these additional cavitation activities, which is a potential risk affecting treatment safety. Therefore, three-dimensional passive acoustic imaging is particularly important for providing a more comprehensive dynamic view of microbubbles. Summary of the invention

[0003] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a three-dimensional real-time passive acoustic imaging method, device, equipment and medium based on row-column addressing ultrasonic transducer to solve the above-mentioned problems.

[0004] The present invention provides a three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers, comprising:

[0005] Passively receiving ultrasonic signals for three-dimensionally monitoring acoustic cavitation activities through a row-column addressed ultrasonic transducer; the row-column addressed ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signals include a row array signal and a column array signal;

[0006] Reconstructing the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field;

[0007] A target frequency band is selected from each frequency band, and a three-dimensional passive cavitation image of the row and column arrays is obtained by cross-correlating and superimposing the three-dimensional sound field of the row array and the three-dimensional sound field of the column array at each frequency in the target frequency band.

[0008] In one embodiment of the present invention, reconstructing a three-dimensional sound field according to the row array signal and the column array signal to obtain a row array three-dimensional sound field and a column array three-dimensional sound field respectively includes:

[0009] Based on the row array signal and the column array signal, respectively determine a row array two-dimensional sound field and a column array two-dimensional sound field;

[0010] By copying or rotating the row array two-dimensional sound field and the column array two-dimensional sound field, a row array three-dimensional sound field and a column array three-dimensional sound field are obtained respectively.

[0011] In one embodiment of the present invention, based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes:

[0012] Performing one-dimensional Fourier transform on the row array signal and the column array signal in the time direction respectively to obtain a first transform result;

[0013] Multiplying the first transformation result and the delay propagation operator respectively to obtain first products;

[0014] Based on the first product, the two-dimensional sound field of the row array and the two-dimensional sound field of the column array are determined by summing along the channel direction.

[0015] In one embodiment of the present invention, based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes:

[0016] Performing one-dimensional Fourier transform on the row array signal and the column array signal in the time direction and the transverse direction respectively to obtain a second transform result;

[0017] Multiplying the second transformation results of the row array and the column array by the spatial domain propagation operator respectively to obtain second products;

[0018] Based on the second product, an inverse Fourier transform is performed along the row array arrangement direction or the column array arrangement direction to determine the row array two-dimensional sound field and the column array two-dimensional sound field.

[0019] In one embodiment of the present invention, based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes:

[0020] Construct at least two sets of apodization functions;

[0021] Based on the ultrasonic signal and each group of the apodization functions, a row array sub-aperture signal and a column array sub-aperture signal are obtained respectively;

[0022] Performing one-dimensional Fourier transform on each of the row array sub-aperture signals and the column array sub-aperture signals in the time direction and the transverse direction respectively to obtain a third transform result;

[0023] Respectively multiplying the third transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the spatial domain propagation operator to obtain third products;

[0024] Sum the third products of the row array and the column array respectively along the channel direction to obtain the row array sub-aperture frequency domain sound field and the column array sub-aperture frequency domain sound field;

[0025] Determining the spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array sub-apertures and the frequency domain sound fields of the column array sub-apertures;

[0026] The row array two-dimensional sound field and the column array two-dimensional sound field are determined according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient.

[0027] In one embodiment of the present invention, based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes:

[0028] Construct at least two sets of apodization functions;

[0029] Based on the ultrasonic signal and each group of the apodization functions, a row array sub-aperture signal and a column array sub-aperture signal are obtained respectively;

[0030] Performing a one-dimensional Fourier transform on each of the row array sub-aperture signals and the column array sub-aperture signals in the time direction to obtain a fourth transform result;

[0031] Respectively multiplying the fourth transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the delay propagation operator to obtain fourth products;

[0032] Sum the fourth products of the row array and the column array respectively along the channel direction to obtain the row array sub-aperture frequency domain sound field and the column array sub-aperture frequency domain sound field;

[0033] Determining the spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array sub-apertures and the frequency domain sound fields of the column array sub-apertures;

[0034] The row array two-dimensional sound field and the column array two-dimensional sound field are determined according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient.

[0035] In one embodiment of the present invention, determining the row array two-dimensional sound field and the column array two-dimensional sound field according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient includes:

[0036] Adding the frequency domain sound fields of the row array subapertures and adding the frequency domain sound fields of the column array subapertures to obtain a first sum of the frequency domain sound fields of the row array subapertures and a second sum of the frequency domain sound fields of the column array subapertures;

[0037] The first sum is multiplied by the spatial weight coefficient of the row array matrix to obtain the row array two-dimensional sound field, and the second sum is multiplied by the spatial weight coefficient of the column array matrix to obtain the column array two-dimensional sound field.

[0038] The three-dimensional real-time passive acoustic imaging device based on row-column addressing ultrasonic transducer provided by the present invention comprises:

[0039] A signal receiving module, used for passively receiving ultrasonic signals for three-dimensionally monitoring acoustic cavitation activities through a row-column addressing ultrasonic transducer; the row-column addressing ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signal includes a row array signal and a column array signal;

[0040] A processing module is used to reconstruct the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field;

[0041] The imaging module selects a target frequency band from each frequency band, and obtains a three-dimensional passive cavitation image of the row and column arrays by cross-correlating and superimposing the three-dimensional sound fields of the row array and the column array at each frequency in the target frequency band.

[0042] The electronic device provided by the present invention comprises:

[0043] one or more processors;

[0044] A storage device is used to store one or more programs. When the one or more programs are executed by the one or more processors, the electronic device implements the three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer.

[0045] The computer-readable storage medium provided by the present invention stores a computer program thereon, and when the computer program is executed by a processor of a computer, the computer is enabled to execute the three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers.

[0046] Beneficial effects of the present invention: The present invention utilizes the characteristics of row and column arrays, and the current traditional linear array two-dimensional ultrasonic passive acoustic imaging technology can be applied in the process of sound field reconstruction. The three-dimensional sound field of the row array and column array is constructed by copying and rotating operations, and finally the artifacts are significantly reduced by calculating the cross-correlation of the two three-dimensional sound fields. Compared with traditional three-dimensional ultrasonic imaging, this method has lower computational complexity. In addition, row and column array passive acoustic imaging can be combined with existing B-mode ultrasonic diagnostic imaging to achieve dual-modal volume imaging, thereby achieving more accurate positioning and monitoring. This technology helps to optimize the visualization monitoring scheme of acoustic cavitation therapy technology and reduce potential risk factors that affect treatment safety and efficiency. .

[0047] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] The drawings herein are incorporated into the specification and constitute a part of the specification, showing embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0049] Figure 1 It is a schematic diagram of a coordinate system for three-dimensional real-time passive acoustic imaging of a row-column addressed ultrasonic transducer shown in an exemplary embodiment of the present application.

[0050] Figure 2 It is a flow chart of a three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer shown in an exemplary embodiment of the present application.

[0051] Figure 3 It is a dual-modal volume section and rendering of the passive acoustic imaging volume image reconstruction result combined with the B-mode image in the experimental example 1 of the present application.

[0052] Figure 4 It is a dual-modal cross-sectional image combining the reconstructed passive acoustic imaging volume image and the B-mode image in the first experimental example of the present application.

[0053] Figure 5 It is a dual-modality image volume section diagram and rendering diagram combining passive acoustic imaging and B-mode ultrasound imaging reconstructed in Experimental Example 2 of the present application. DETAILED DESCRIPTION

[0054] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0055] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0056] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0057] It is worth noting that the number of channels and corresponding cable connections required by conventional three-dimensional ultrasound imaging probes (such as array probes) increase exponentially with the increase in aperture, which makes it difficult for traditional ultrasound imaging systems to afford these high-channel requirements. To solve this problem, sparse arrays have been proposed as an alternative, but often require compromises in imaging quality. Row-column addressing arrays are a more effective alternative that address the elements in a two-dimensional array along rows and columns, which can be viewed as two orthogonal long arrays of elements. This structure greatly reduces the number of channels required for imaging, while reducing hardware complexity and cost while maintaining high imaging quality.

[0058] The present application proposes a three-dimensional real-time passive acoustic imaging method based on a row-column addressed ultrasonic transducer. The method uses the correlation between the acoustic fields reconstructed by the signals received by the row array and the column array to calculate the mutual power spectrum between the frequency domain acoustic fields, thereby achieving high-quality real-time three-dimensional passive acoustic imaging. By utilizing the characteristics of the row array and the column array, the current traditional linear array two-dimensional ultrasonic passive acoustic imaging technology can be applied in the process of acoustic field reconstruction. The three-dimensional acoustic fields of the row array and the column array are constructed by copying and rotating operations, and finally the artifacts are significantly reduced by calculating the cross-correlation of the two three-dimensional acoustic fields. Compared with the three-dimensional ultrasonic imaging of the traditional planar array probe, this method has lower computational complexity. In addition, the row-column array passive acoustic imaging can be combined with the existing B-mode ultrasonic diagnostic imaging (B-ultrasound for short) to achieve dual-modal volume imaging, thereby achieving more accurate positioning and monitoring. This technology helps to optimize the visualization monitoring scheme of acoustic cavitation therapy technology and reduce potential risk factors that affect the safety and efficiency of treatment.

[0059] Figure 1 FIG. 1 is a schematic diagram of a coordinate system for three-dimensional real-time passive acoustic imaging of a row-column addressed ultrasonic transducer according to an exemplary embodiment of the present application. Figure 1 As shown in the figure, P is the position of the sound source, r is the intersection of the spherical wavefront of the sound source and the array element, and the coordinate system includes x-axis, y-axis and z-axis, wherein the x-axis is set in the row array arrangement direction; the y-axis is set in the column array arrangement direction.

[0060] See also Figure 2 , Figure 2 It is a flow chart of a three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer shown in an exemplary embodiment of the present application.

[0061] like Figure 2 As shown, in an exemplary embodiment, a three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers is described in detail as follows:

[0062] Step 1: Data collection.

[0063] For example, to monitor microbubble acoustic cavitation activity in three dimensions, a row-column addressed ultrasonic transducer is used to passively receive ultrasonic signals. Figure 1 As shown, the row-column addressing ultrasonic transducer can be regarded as consisting of two mutually orthogonal row arrays and column arrays, which receive row array signals and column array signals respectively. Both the row array and the column array contain N equally spaced long array elements.

[0064] Step 2: Use the row array signal and the column array signal to reconstruct the three-dimensional sound field respectively.

[0065] For example, for a long array element array, when the angular wave effect is small enough and can be ignored, the signal delay from the sound source on a certain voxel in the imaging area to the long array element can be regarded as the distance from the point to the line segment where the long array element is located divided by the sound speed c. Therefore, the ultrasonic signal received by the row and column addressing ultrasonic transducer can be firstly calculated for the row array two-dimensional sound field and the column array two-dimensional sound field, and then the row array three-dimensional sound field and the column array three-dimensional sound field can be calculated by copying or rotating operations.

[0066] It should also be noted that, in order to simplify the formula expression, the following only shows the derivation of the row array three-dimensional sound field p from the row array signal R (x, y, z, ω) process, the three-dimensional sound field p of the array signal can be calculated by similar expression C (x,y,z,ω), where ω represents the angular frequency.

[0067] Specifically, for a row array two-dimensional sound field The calculation includes three methods: frequency domain delay superposition method, angular spectrum method and method based on frequency domain apodization cross-correlation operator (hereinafter referred to as apodization cross-correlation method). All three methods are implemented in Cartesian coordinate system. The angular spectrum method has low algorithm complexity and higher computational efficiency than the frequency domain delay superposition method. The apodization cross-correlation method is to optimize the image and reduce artifacts by applying the apodization cross-correlation operator on the basis of the existing frequency domain sound field estimation method.

[0068] Method 1: Frequency domain delay and superposition method.

[0069] Specifically, for the row array signal p R (x n ,z0,t) performs a one-dimensional Fourier transform in the time t direction to obtain p R (x n ,z0,ω), then multiply it with the propagation operator, and finally sum it along the channel direction to obtain the two-dimensional sound field of the row array Line array two-dimensional sound field The calculation formula (represented as formula (1)) is as follows:

[0070]

[0071] in,

[0072] It's location The distance to the nth row element.

[0073] Method 2: Angular spectrum method

[0074] Specifically, for the row array signal p R (x n,z0,t) performs a two-dimensional Fourier transform at time t and in the lateral x direction (when calculating the two-dimensional sound field of a column array, it is replaced by the lateral y direction), then multiplies it with the propagation operator, and finally performs an inverse Fourier transform along the lateral x direction to obtain the two-dimensional sound field of the row array Line array two-dimensional sound field The calculation formula (represented as formula (2)) is as follows:

[0075]

[0076] Among them, k x is the wave number in the transverse x direction, c is the sound speed in the homogeneous medium, and is the Fourier transform along the transverse x direction and time t, is the inverse Fourier transform along the lateral x direction.

[0077] Method 3: Apodization cross-correlation method

[0078] Specifically, the apodization cross-correlation method uses a frequency domain apodization cross-correlation operator to calculate spatial weights based on the existing frequency domain sound field calculation method, and multiplies the spatial weights with the frequency domain sound field to reduce imaging artifacts.

[0079] First, construct J groups (J ≥ 2) of apodization functions a with N elements. j (n). Taking J = 2 as an example, two sets of apodization functions a1(n) and a2(n) are constructed. In each apodization function, every A adjacent activated elements are interlaced with A inactivated elements, where the activated elements are 1 and the inactivated elements are 0. The expression formula of the apodization function a1(n) (denoted as formula (3)) and the expression formula of a2(n) (denoted as formula (4)) are as follows:

[0080]

[0081] in is the floor function, and mod is the remainder function.

[0082] Two sets of corresponding row array subaperture signals p jR (x n ,z0,t) is received by the row array signal p R (x n ,z0,t) and the apodization function a j (n) is multiplied to obtain the row array subaperture signal p jR (x n ,z0,t) (denoted as formula (5)) is as follows:

[0083] p jR (x n ,z0,t)=pR (x n ,z0,t)a j (n)

[0084] Where (x n ,z0) is the position of the nth row element, j = 1,2. Row array subaperture frequency domain sound field By changing p jR (x n ,z0,t) replaces p in formula (1) or (2) R (x n ,z0,t) is obtained. Then the frequency domain sound field of the array sub-aperture is and The normalized cross-correlation spatial weight coefficient of It is calculated by the following formula (denoted as formula (6)).

[0085]

[0086] Finally, the spatial weights of the row array are Multiplying the sum of the frequency domain sound fields of the two row array subapertures gives the complete row array two-dimensional sound field The specific calculation formula (recorded as formula (7)) is as follows:

[0087]

[0088] Then, by replicating or rotating the row array 2D sound field As a result, the three-dimensional sound field p of the row array is quickly obtained. R (x,y,z,ω), row array three-dimensional sound field p R The calculation formula of (x, y, z, ω) (represented as formula (8)) is as follows:

[0089]

[0090] The aperture size of the row and column array is S×S. The three-dimensional sound field p of the column array can be obtained by similar expressions of formulas (1)-(8): C (x,y,z,ω).

[0091] Step 3: Calculate the cross-correlation between the three-dimensional sound field of the row array and the three-dimensional sound field of the column array.

[0092] Specifically, by cross-correlating and superimposing the three-dimensional sound field of the row array and the three-dimensional sound field of the column array at each frequency in the selected frequency band Ω, the three-dimensional passive cavitation image I(x, y, z) of the row and column array is obtained. The calculation formula of the three-dimensional passive cavitation image I(x, y, z) (denoted as formula (9)) is as follows:

[0093]

[0094] in, represents the real part of a complex number, and * represents the conjugate.

[0095] Experimental Example 1: Silicone Tube Blood Vessel Simulator

[0096] Step 1: Data Collection

[0097] Passive acoustic imaging was performed using a row-column addressed ultrasonic transducer (referred to as transducer) with 128+128 channels and an array element spacing of 0.2mm. The center frequency of the transducer was 6MHz, the sampling frequency was 25MHz, and all channels passively received microbubble acoustic cavitation signals for reconstructing the acoustic cavitation activity image. Focused ultrasound with a frequency of 1MHz and a peak negative pressure of 0.5MPa acted on a silicone tube with an inner diameter of 1mm at a repetition rate of 16Hz to stimulate microbubble cavitation activity in the silicone tube. The silicone tube was placed at a depth of about 30mm to simulate blood vessels in the body. In order to verify the ability of row-column array passive acoustic imaging to locate the cavitation source, B-ultrasound imaging was performed before each focused acoustic pressure excitation of cavitation, and then the cavitation signal was passively received to synchronously monitor the cavitation activity position and the silicone tube position.

[0098] Step 2: Use row array signals and column array signals to reconstruct the 3D sound field

[0099] According to formula (1), formula (2) and formula (7), the frequency domain delay superposition method, angular spectrum method and apodization cross-correlation method (based on angular spectrum method) are used respectively to calculate the two-dimensional sound field of the row array through the row array signal and column array signal Two-dimensional sound field with column array In this experimental example, all frequency components covering the probe frequency band (2.95-8.05 MHz) and the harmonic frequency components (n±0.05 MHz, n=3-8), superharmonic frequency components (0.5n±0.05 MHz, n=7-17) and broadband frequency components ((0.5n+0.25)±0.05 MHz, n=6-16) within the frequency band were selected to reconstruct the images. The imaging range was selected as the area directly below the row and column array aperture and with a depth of 0 to 50 mm. The passive cavitation volume image size was 128×128×250, and the interval Δx=Δy=Δz=0.2 mm. Formula (8) was applied to obtain the row array three-dimensional sound field and the column array three-dimensional sound field by copying the two-dimensional sound field reconstruction results.

[0100] Step 3: Calculate the cross-correlation between the row array 3D sound field and the column array 3D sound field

[0101] According to formula (9), the cross-correlations of the three-dimensional sound field of the row array and the three-dimensional sound field of the column array at each frequency in the selected frequency band are superimposed to obtain the three-dimensional passive acoustic cavitation image of the row and column arrays.

[0102] In the single silicone tube and double parallel silicone tube vascular phantom experiments, all frequency components covering the probe frequency band were used to reconstruct passive acoustic cavitation volume images using the frequency domain delay superposition method, angular spectrum method, and apodization cross-correlation method. The results were combined with the B-mode image to form a dual-modal volume section and rendering as shown in Figure 2. Figure 3 shown. Figure 3 (a) and (b) are dual-modality images of passive acoustic imaging combined with B-mode imaging reconstructed by frequency domain delay superposition method, angular spectrum method and apodization cross-correlation method in single silicone tube and double parallel silicone tube vascular phantom experiments, respectively. Each dual-modality imaging result shows its cross-sectional image and volume rendering. The purple and pink lines indicate the relative positions of the yz and xz sections.

[0103] In the single silicone tube experiment, the harmonic, superharmonic and broadband frequency components within the frequency band were selected, and the dual-modality cross-sectional images combining the passive cavitation volume image and the B-mode image were reconstructed using the apodization cross-correlation method. Figure 4 As shown in (a), Figure 4 (b) shows the spectrum of the received signal under four different conditions.

[0104] Figure 4 (a-d) are volume slices of passive acoustic imaging combined with B-mode imaging reconstructed using harmonic, superharmonic, and broadband frequency components by apodization cross-correlation under four different conditions of the silicone tube phantom experiment. The purple and pink lines indicate the relative positions of the yz and xz sections. Figure 4 In (a), no microbubbles were injected into the silicone tube and an external sound pressure of 0.1 MPa was applied. In (b)-(d), microbubbles were injected into the tube and 0.1 MPa, 0.7 MPa and 1.2 MPa sound pressure were applied. (e) is the power spectrum of the signal received by the 64 channels of the row and column array in each case.

[0105] Experimental Example 2: Liver Tumor Mouse Model

[0106] Step 1: Data Collection

[0107] Passive acoustic imaging was performed using a row-column addressed ultrasound transducer with 128+128 channels and an array element spacing of 0.2mm. The transducer center frequency was 6MHz, the sampling frequency was 25MHz, and all channels passively received microbubble cavitation signals for reconstructing passive cavitation images. Focused ultrasound with a frequency of 1MHz and a peak negative pressure of 0.75MPa acted on the mouse tumor area at a repetition frequency of 16Hz to stimulate microbubble cavitation activity in the tumor.

[0108] In order to verify the ability of row-column array passive acoustic imaging to locate the cavitation source, B-ultrasound imaging was performed before each focused acoustic pressure excitation of cavitation, followed by passive reception of cavitation signals to synchronously monitor the cavitation activity position and the silicone tube position.

[0109] Step 2: Reconstruct the 3D sound field from the row array signal and column array signal respectively

[0110] According to formula (1), formula (2) and formula (7), the frequency domain delay superposition method, angular spectrum method and apodization cross-correlation method are used respectively to calculate the row array two-dimensional sound field through the row array signal and column array signal Two-dimensional sound field with column array In this experimental example, all frequency components covering the probe frequency band (2.95-8.05 MHz) were selected to reconstruct the image. The imaging range was selected as the area directly below the row and column array aperture and with a depth of 0 to 50 mm. The passive cavitation volume image size was 128×128×250, and the interval Δx=Δy=Δz=0.2 mm. Formula (8) was applied to obtain the row array three-dimensional sound field and the column array three-dimensional sound field by copying the two-dimensional sound field reconstruction results.

[0111] Step 3: Calculate the 3D sound field cross-correlation between the row array and the column array

[0112] According to formula (9), the cross-correlations of the three-dimensional sound field of the row array and the three-dimensional sound field of the column array at each frequency in the selected frequency band are superimposed to obtain the three-dimensional passive cavitation image of the row and column array.

[0113] The cross-sectional images of the row and column array passive acoustic imaging at the peak position are shown in the figure using the frequency domain delay and superposition method, angular spectrum method and apodization cross-correlation method to reconstruct the sound field respectively. Figure 5 (a)-(c) show the dual-modal volume rendering using the apodization cross-correlation method. Figure 5 As shown in (d), the two white arrows indicate two cavitation sources at different depths.

[0114] exist Figure 5 In the figure, dual-modality image sections of passive acoustic imaging combined with B-mode ultrasound imaging reconstructed by the frequency domain delay and superposition method (a), the angular spectrum method (b), and the apodization cross-correlation method (c) in an in vivo experiment in a liver tumor mouse model. (d) is the volume rendering corresponding to (c). The purple and pink lines indicate the relative positions of the yz and xz sections. The white dashed line indicates the tumor location.

[0115] In an exemplary embodiment, a three-dimensional real-time passive acoustic imaging device based on row-column addressing ultrasound transducers includes:

[0116] A signal receiving module, used for passively receiving ultrasonic signals for three-dimensionally monitoring acoustic cavitation activities through a row-column addressing ultrasonic transducer; the row-column addressing ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signal includes a row array signal and a column array signal;

[0117] A processing module is used to reconstruct the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field;

[0118] The imaging module selects a target frequency band from each frequency band, and obtains a three-dimensional passive cavitation image of the row and column arrays by cross-correlating and superimposing the three-dimensional sound fields of the row array and the column array at each frequency in the target frequency band.

[0119] It should be noted that the three-dimensional real-time passive acoustic imaging device based on row-column addressed ultrasonic transducers provided in the above embodiment and the three-dimensional real-time passive acoustic imaging method based on row-column addressed ultrasonic transducers provided in the above embodiment belong to the same concept, wherein the specific manner in which each module and unit performs the operation has been described in detail in the method embodiment and will not be repeated here. In practical applications, the three-dimensional real-time passive acoustic imaging device based on row-column addressed ultrasonic transducers provided in the above embodiment can allocate the above functions to different functional modules as needed, that is, divide the internal structure of the device into different functional modules to complete all or part of the functions described above, and this is not limited here.

[0120] An embodiment of the present application also provides an electronic device, comprising: one or more processors; a storage device for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the electronic device implements the three-dimensional real-time passive acoustic imaging method based on row-column addressed ultrasonic transducers provided in the above-mentioned embodiments.

[0121] Another aspect of the present application also provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor of a computer, the computer executes the three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers as described above. The computer-readable storage medium may be included in the electronic device described in the above embodiment, or may exist independently without being assembled into the electronic device.

[0122] Another aspect of the present application also provides a computer program product or a computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and the processor executes the computer instructions, so that the computer device executes the three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers provided in the above-mentioned various embodiments.

[0123] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer, characterized in that: include: Passively receiving ultrasonic signals for three-dimensional monitoring of acoustic cavitation activities through row-column addressed ultrasonic transducers; The row-column addressing ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signal includes a row array signal and a column array signal; Reconstructing the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field; A target frequency band is selected from each frequency band, and a three-dimensional passive cavitation image of the row and column arrays is obtained by cross-correlating and superimposing the three-dimensional sound field of the row array and the three-dimensional sound field of the column array at each frequency in the target frequency band.

2. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 1, characterized in that: Reconstructing the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field includes: Based on the row array signal and the column array signal, respectively determine a row array two-dimensional sound field and a column array two-dimensional sound field; By copying or rotating the row array two-dimensional sound field and the column array two-dimensional sound field, a row array three-dimensional sound field and a column array three-dimensional sound field are obtained respectively.

3. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 2 is characterized in that: Based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes: Performing one-dimensional Fourier transform on the row array signal and the column array signal in the time direction respectively to obtain a first transform result; Multiplying the first transformation result and the delay propagation operator respectively to obtain first products; Based on the first product, the two-dimensional sound field of the row array and the two-dimensional sound field of the column array are determined by summing along the channel direction.

4. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 2, characterized in that: Based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes: Performing one-dimensional Fourier transform on the row array signal and the column array signal in the time direction and the transverse direction respectively to obtain a second transform result; Multiplying the second transformation results of the row array and the column array by the spatial domain propagation operator respectively to obtain second products; Based on the second product, an inverse Fourier transform is performed along the transverse direction to determine a two-dimensional sound field of a row array and a two-dimensional sound field of a column array, respectively.

5. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 2, characterized in that: Based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes: Construct at least two sets of apodization functions; Based on the ultrasonic signal and each group of the apodization functions, a row array sub-aperture signal and a column array sub-aperture signal are obtained respectively; Performing one-dimensional Fourier transform on each of the row array sub-aperture signals and the column array sub-aperture signals in the time direction and the transverse direction respectively to obtain a third transform result; Respectively multiplying the third transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the spatial domain propagation operator to obtain third products; Sum the third products of the row array and the column array respectively along the channel direction to obtain the row array sub-aperture frequency domain sound field and the column array sub-aperture frequency domain sound field; Determining the spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array sub-apertures and the frequency domain sound fields of the column array sub-apertures; The row array two-dimensional sound field and the column array two-dimensional sound field are determined according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient.

6. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 2, characterized in that: Based on the row array signal and the column array signal, determining the row array two-dimensional sound field and the column array two-dimensional sound field respectively includes: Construct at least two sets of apodization functions; Based on the ultrasonic signal and each group of the apodization functions, a row array sub-aperture signal and a column array sub-aperture signal are obtained respectively; Performing a one-dimensional Fourier transform on each of the row array sub-aperture signals and the column array sub-aperture signals in the time direction to obtain a fourth transform result; Respectively multiplying the fourth transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the delay propagation operator to obtain fourth products; Sum the fourth products of the row array and the column array respectively along the channel direction to obtain the row array sub-aperture frequency domain sound field and the column array sub-aperture frequency domain sound field; Determining the spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array sub-apertures and the frequency domain sound fields of the column array sub-apertures; The row array two-dimensional sound field and the column array two-dimensional sound field are determined according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient.

7. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducer according to claim 2, characterized in that: Determining the row array two-dimensional sound field and the column array two-dimensional sound field according to the row array sub-aperture frequency domain sound field, the column array sub-aperture frequency domain sound field and the spatial weight coefficient includes: Adding the frequency domain sound fields of the row array subapertures and adding the frequency domain sound fields of the column array subapertures to obtain a first sum of the frequency domain sound fields of the row array subapertures and a second sum of the frequency domain sound fields of the column array subapertures; The first sum is multiplied by the spatial weight coefficient of the row array matrix to obtain the row array two-dimensional sound field, and the second sum is multiplied by the spatial weight coefficient of the column array matrix to obtain the column array two-dimensional sound field.

8. A three-dimensional real-time passive acoustic imaging device based on row-column addressing ultrasonic transducer, characterized in that: include: A signal receiving module, used for passively receiving ultrasonic signals for three-dimensional monitoring of acoustic cavitation activities through row-column addressing ultrasonic transducers; The row-column addressing ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signal includes a row array signal and a column array signal; A processing module is used to reconstruct the three-dimensional sound field according to the row array signal and the column array signal to obtain the row array three-dimensional sound field and the column array three-dimensional sound field; The imaging module selects a target frequency band from each frequency band, and obtains a three-dimensional passive cavitation image of the row and column arrays by cross-correlating and superimposing the three-dimensional sound fields of the row array and the column array at each frequency in the target frequency band.

9. A device, characterized in that: include: one or more processors and memory, A computer program is stored in the memory, and when the one or more processors execute the computer program, the device is caused to perform the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, which, when executed by one or more processors, causes the device to perform the method according to any one of claims 1 to 7.

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