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

Abstract

The present invention provides a three-dimensional real-time passive acoustic imaging method, apparatus, device, and medium based on row-column addressed ultrasonic transducers. The method comprises: passively receiving ultrasonic signals for three-dimensionally monitoring microbubble acoustic cavitation activity via a row-column addressed ultrasonic transducer; the row-column addressed ultrasonic transducer comprises a row array and a column array, and the ultrasonic signals comprise row array signals and column array signals; reconstructing a three-dimensional acoustic field based on the row array signals and the column array signals, respectively, to obtain a row array three-dimensional acoustic field and a column array three-dimensional acoustic field; selecting a target frequency band within each frequency band, and obtaining a three-dimensional passive cavitation image of the row and column arrays by cross-correlating and superimposing the row array three-dimensional acoustic field and the column array three-dimensional acoustic field at each frequency within the target frequency band. This application can effectively reduce artifacts and achieve more accurate positioning and monitoring.

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] Numerous clinical studies have demonstrated that microbubble-mediated ultrasound cavitation therapy can effectively assist drug delivery and improve treatment outcomes for diseases such as liver and pancreatic cancer. This adjunctive therapy primarily mediates the desired biological effects through the mechanical effects of microbubble cavitation. However, microbubble cavitation activity is highly stochastic. In particular, larger microbubbles, at the same acoustic pressure, are more prone to transient cavitation and rupture, potentially forming high-energy jets on the soft tissue surface and damaging surrounding healthy tissue. To ensure the safety and efficacy of microbubble-mediated ultrasound cavitation therapy, reduce the risk of damage to healthy tissue, and improve the accuracy of targeted drug delivery, real-time imaging, monitoring, and control of the state and distribution of microbubbles in vivo are crucial. Currently, most passive acoustic imaging methods only provide information on cavitation activity in two-dimensional sections and are unable to dynamically capture three-dimensional cavitation activity. The focal region of a focused ultrasound beam is a three-dimensional ellipsoid, which can easily induce cavitation activity outside the imaging plane and in non-target locations. Relying solely on two-dimensional imaging can overlook this additional cavitation activity, posing a potential risk to treatment safety. Therefore, three-dimensional passive acoustic imaging is crucial for providing a more comprehensive view of microbubble dynamics. Summary of the Invention

[0003] In view of the above-mentioned shortcomings of the prior art, the 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 transducers to solve the above-mentioned problems.

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

[0005] Passively receiving ultrasonic signals for three-dimensionally monitoring acoustic cavitation activity 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 row array signals and column array signals;

[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 the three-dimensional passive cavitation images of the row and column arrays are obtained 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.

[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 determining a row array two-dimensional sound field and a column array two-dimensional sound field;

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

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

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

[0013] multiplying the first transformation result and the delay propagation operator respectively to obtain a first product;

[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, determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal 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, determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal 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] 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 respectively to obtain third products;

[0024] Sum the third products of the row array and the column array 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 spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array subapertures and the frequency domain sound fields of the column array subapertures, respectively;

[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, determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal 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] multiplying the fourth transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the delay propagation operator respectively to obtain fourth products;

[0032] Sum the fourth products of the row array and the column array 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 spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array subapertures and the frequency domain sound fields of the column array subapertures, respectively;

[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 present invention provides a three-dimensional real-time passive acoustic imaging device based on a row-column addressing ultrasonic transducer, comprising:

[0039] A signal receiving module, configured to passively receive ultrasonic signals for three-dimensionally monitoring acoustic cavitation activity via a row-column addressable ultrasonic transducer; the row-column addressable ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signals include row array signals and column array signals;

[0040] A processing module is configured to reconstruct 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;

[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 includes:

[0043] one or more processors;

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

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

[0046] The beneficial effects of the present invention are as follows: By utilizing the characteristics of row and column arrays, the present invention can apply current traditional linear array two-dimensional passive ultrasonic imaging technology to the sound field reconstruction process. Three-dimensional sound fields of row and column arrays are constructed through replication and rotation operations. Ultimately, by calculating the cross-correlation of the two three-dimensional sound fields, artifacts are significantly reduced. Compared to 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 volumetric imaging, thereby enabling more precise positioning and monitoring. This technology helps 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 accompanying drawings are incorporated into and constitute a part of the specification, illustrating embodiments consistent with the present application and, together with the specification, serving to explain the principles of the present application. It is obvious that the drawings described below are merely some embodiments of the present application, and a person of ordinary skill in the art can derive other drawings based on these drawings without inventive effort. In the drawings:

[0049] Figure 1 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.

[0050] Figure 2 3D real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers is shown as a flowchart of an exemplary embodiment of the present application.

[0051] Figure 3 It is a dual-modal volume section and rendering image combining the passive acoustic imaging volume image reconstruction result and the B-mode image in Experimental Example 1 of this application.

[0052] Figure 4 This is a dual-modal cross-sectional image combining the reconstructed passive acoustic imaging volume image and the B-mode image in Experimental Example 1 of the present application.

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

[0054] The following describes the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art will readily appreciate the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments, and the various details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are intended only to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0055] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. Therefore, the illustrations only show components related to the present invention and are not 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 complex.

[0056] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring the embodiments of the present invention.

[0057] It is worth noting that the number of channels and corresponding cable connections required by conventional three-dimensional ultrasound imaging probes (such as area array probes) increases exponentially with the increase in aperture, making it difficult for traditional ultrasound imaging systems to bear 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. They address the elements in a two-dimensional area array along rows and columns and can be viewed as two orthogonal long arrays of array elements. This structure significantly reduces the number of channels required for imaging, while reducing hardware complexity and cost while maintaining high imaging quality.

[0058] This application proposes a three-dimensional real-time passive acoustic imaging method based on row-column addressed ultrasonic transducers. This method uses the correlation between the sound fields reconstructed by the signals received by the row array and the column array to calculate the cross-power spectrum between the frequency domain sound 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 sound field reconstruction process. The three-dimensional sound fields of the row array and the column array are constructed by copying and rotating operations. Finally, by calculating the cross-correlation of the two three-dimensional sound fields, the artifacts are significantly reduced. Compared with the three-dimensional ultrasonic imaging of the traditional planar array probe, this method has lower computational complexity. In addition, 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 treatment safety and efficiency.

[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 the x-axis, y-axis and z-axis, where 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 3D real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers is shown as a flowchart of 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 addressed ultrasonic transducer can be considered to be composed 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 element array, when the angular wave effect is sufficiently small to be negligible, the signal delay from the sound source at a certain voxel in the imaging area to the long element can be considered as the distance from that point to the line segment containing the long element divided by the speed of sound, c. Therefore, the ultrasonic signals received by the row-column addressed ultrasonic transducers can be first calculated for the two-dimensional row array sound field and the two-dimensional column array sound field, and then the three-dimensional row array sound field and the three-dimensional column array sound field can be calculated through replication or rotation 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 two-dimensional sound field of a row array Three methods are used for calculation, including the frequency-domain delay-and-add method, the angular spectrum method, and a method based on the frequency-domain apodized cross-correlation operator (hereinafter referred to as the apodized cross-correlation method). All three methods are implemented in a Cartesian coordinate system. The angular spectrum method has low algorithmic complexity and higher computational efficiency than the frequency-domain delay-and-add method. The apodized cross-correlation method applies the apodized cross-correlation operator to existing frequency-domain sound field estimation methods to optimize the image and reduce artifacts.

[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 (recorded 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 in the time t and the transverse x direction (when calculating the two-dimensional sound field of the column array, it is replaced by the transverse y direction), then multiplies it with the propagation operator, and finally performs an inverse Fourier transform along the transverse x direction to obtain the two-dimensional sound field of the row array Line array two-dimensional sound field The calculation formula (denoted as formula (2)) is as follows:

[0075]

[0076] Among them, k x is the wave number in the transverse x direction, c is the speed of sound in the homogeneous medium, and is the Fourier transform along the transverse x direction and time t, is the inverse Fourier transform along the transverse 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 active elements are interleaved with A inactive elements, where active elements are 1 and inactive elements are 0. The expression formulas for the apodization functions a1(n) (denoted as formula (3)) and 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 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 adding p jR (x n ,z0,t) replace 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 added Multiplying the sum of the frequency domain sound fields of the two row array sub-apertures to obtain the complete row array two-dimensional sound field The specific calculation formula (recorded as formula (7)) is as follows:

[0087]

[0088] Then, by copying 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) (denoted 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 fields of the row array and the column array at each frequency within the selected frequency band Ω, the three-dimensional passive cavitation image I(x, y, z) of the row and column arrays 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, Indicates taking the real part of a complex number, and * indicates conjugate.

[0095] Experimental Example 1: Silicone Tube Vascular Phantom

[0096] Step 1: Data Collection

[0097] Passive acoustic imaging was performed using a 128+128-channel, 0.2mm-interface array-addressed ultrasonic transducer (referred to as the transducer). The transducer had a center frequency of 6MHz and a sampling frequency of 25MHz. All channels passively received microbubble acoustic cavitation signals to reconstruct images of acoustic cavitation activity. Focused ultrasound with a frequency of 1MHz and a peak negative pressure of 0.5MPa was applied to a 1mm inner diameter silicone tube at a repetition rate of 16Hz, stimulating microbubble cavitation activity within the silicone tube. The silicone tube was placed at a depth of approximately 30mm to simulate a blood vessel in the body. 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-induced cavitation, followed by passive reception of cavitation signals to simultaneously monitor the cavitation activity location 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 within the band (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) were selected for image reconstruction. The imaging range was selected to be the area directly below the row and column array apertures, with a depth of 0 to 50 mm. The passive cavitation volume image size was 128 × 128 × 250, with an interval of Δx = Δy = Δz = 0.2 mm. Applying formula (8), the three-dimensional sound field of the row array and the three-dimensional sound field of the column array were obtained by replicating 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 dual 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 dual-modal volume sections and renderings as shown in Figure 2. Figure 3 shown. Figure 3 (a) and (b) show dual-modality images of passive acoustic imaging combined with B-mode imaging, reconstructed using the frequency-domain delay-and-addition method, the angular spectrum method, and the apodized cross-correlation method, respectively, for single- and dual-parallel silicone tube vascular phantoms. Each dual-modality imaging result shows a cross-sectional image and a 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 apodization cross-correlation method was used to reconstruct the dual-modal cross-sectional image of the passive cavitation volume image combined with the B-mode image. 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) show volumetric slices of passive acoustic imaging combined with B-mode imaging using harmonic, superharmonic, and broadband frequency components reconstructed using apodized cross-correlation under four different conditions in a silicone tube phantom experiment. The purple and pink lines indicate the relative positions of the yz and xz sections. Figure 4 (a) shows the silicone tube without microbubbles and with an applied sound pressure of 0.1 MPa. (b)-(d) show the tube with microbubbles and with applied sound pressures of 0.1 MPa, 0.7 MPa, and 1.2 MPa. (e) shows 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 128+128-channel, row-column addressed ultrasound transducer with an element spacing of 0.2 mm. The transducer had a center frequency of 6 MHz and a sampling frequency of 25 MHz. All channels passively received microbubble cavitation signals for reconstructing passive cavitation images. Focused ultrasound with a frequency of 1 MHz and a peak negative pressure of 0.75 MPa was applied to the mouse tumor area at a repetition rate of 16 Hz, stimulating microbubble cavitation activity within the tumor.

[0108] 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, thereby simultaneously monitoring the cavitation activity location 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 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's frequency band (2.95 to 8.05 MHz) were selected for image reconstruction. The imaging range was selected to be the area directly below the row and column array apertures, with a depth of 0 to 50 mm. The passive cavitation volume image size was 128 × 128 × 250, with an interval of Δx = Δy = Δz = 0.2 mm. Formula (8) was applied to replicate the two-dimensional sound field reconstruction results to obtain the three-dimensional sound fields of the row and column arrays.

[0111] Step 3: Calculate the three-dimensional 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 were reconstructed using the frequency-domain delay-and-addition method (a), the angular spectrum method (b), and the apodized cross-correlation method (c) in an in vivo mouse model of liver tumors. (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 addressed ultrasonic transducers includes:

[0116] A signal receiving module, configured to passively receive ultrasonic signals for three-dimensionally monitoring acoustic cavitation activity via a row-column addressable ultrasonic transducer; the row-column addressable ultrasonic transducer is composed of a row array and a column array, and the ultrasonic signals include row array signals and column array signals;

[0117] A processing module is configured to reconstruct 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;

[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-mentioned embodiments and the three-dimensional real-time passive acoustic imaging method based on row-column addressed ultrasonic transducers provided in the above-mentioned embodiments are based on the same concept, wherein the specific manner in which each module and unit performs operations has been described in detail in the method embodiments and will not be repeated here. In actual applications, the three-dimensional real-time passive acoustic imaging device based on row-column addressed ultrasonic transducers provided in the above-mentioned embodiments can, as needed, allocate the above-mentioned functions to different functional modules, 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 provides a computer-readable storage medium having a computer program stored thereon. When executed by a computer processor, the computer program causes the computer to perform the aforementioned method for three-dimensional real-time passive acoustic imaging based on a row-column addressed ultrasonic transducer. The computer-readable storage medium may be included in the electronic device described in the above embodiments, or may exist independently and not be incorporated into the electronic device.

[0122] Another aspect of the present application provides a computer program product or 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 executes the computer instructions, causing the computer device to perform the three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers provided in each of the above 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 skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, any equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to 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 transducers, characterized in that: include: Ultrasonic signals for three-dimensional monitoring of acoustic cavitation activity are passively received by row-column addressed ultrasonic transducers; The row-column addressable 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 fields of the row array and the column array at each frequency within the target frequency band. 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 determining a row array two-dimensional sound field and a column array two-dimensional sound field; The row array three-dimensional sound field and the column array three-dimensional sound field are obtained respectively by copying or rotating the row array two-dimensional sound field and the column array two-dimensional sound field.

2. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers according to claim 1, characterized in that: Determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal, respectively, includes: Performing a one-dimensional Fourier transform on the row array signal and the column array signal in the time direction to obtain a first transform result; multiplying the first transformation result and the delay propagation operator respectively to obtain a first product; 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.

3. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers according to claim 1, characterized in that: Determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal, 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.

4. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers according to claim 1, characterized in that: Determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal, 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; 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 respectively to obtain third products; Sum the third products of the row array and the column array 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 spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array subapertures and the frequency domain sound fields of the column array subapertures, respectively; 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.

5. The three-dimensional real-time passive acoustic imaging method based on row-column addressing ultrasonic transducers according to claim 1, characterized in that: Determining a row array two-dimensional sound field and a column array two-dimensional sound field based on the row array signal and the column array signal, 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; multiplying the fourth transformation results of the row array sub-aperture signal and the column array sub-aperture signal by the delay propagation operator respectively to obtain fourth products; Sum the fourth products of the row array and the column array 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 spatial weight coefficients of the row array matrix and the column array matrix based on the frequency domain sound fields of the row array subapertures and the frequency domain sound fields of the column array subapertures, respectively; 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 transducers according to claim 1, 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.

7. A three-dimensional real-time passive acoustic imaging device based on row-column addressing ultrasonic transducers, characterized in that: include: a signal receiving module for passively receiving ultrasonic signals for three-dimensionally monitoring acoustic cavitation activities through row-column addressing ultrasonic transducers; The row-column addressable 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 configured to reconstruct 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; An imaging module selects a target frequency band from among the frequency bands, 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 three-dimensional sound fields of the column array at each frequency within the target frequency band; 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 determining a row array two-dimensional sound field and a column array two-dimensional sound field; The row array three-dimensional sound field and the column array three-dimensional sound field are obtained respectively by copying or rotating the row array two-dimensional sound field and the column array two-dimensional sound field.

8. 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 6.

9. 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 6.

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