Ultrasonic image correction method, device and medium for flexible ultrasonic probe

Abstract

The present application provides an ultrasonic image correction method, device, and medium for a flexible ultrasonic probe, including: based on a single-transmit-multiple-receive signal transmission and reception mode, the probe's N array elements sequentially act as transmitting array elements to transmit pulsed sound waves, and all array elements simultaneously receive echo signals to obtain an original radio frequency signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points; calculating the correlation between channel signals based on the original radio frequency signal; constructing a loss function based on the correlation, the loss function including a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term; estimating the true array element position through gradient descent iterative calculation; and reconstructing an ultrasonic image based on the estimated true array element position. Embodiments of the present application can achieve continuous adaptive calibration at low cost, avoiding manual intervention.

Description

Technical Field

[0001] The present application relates to the field of ultrasonic imaging technology, and in particular to an ultrasonic image correction method, device, and medium for a flexible ultrasonic probe. Background Art

[0002] Flexible ultrasound probes, due to their unique materials and structural design, offer significant advantages in the field of medical diagnosis, but they also have certain limitations. When a flexible ultrasound probe is attached to the surface of human skin, the probe's geometry changes, and the relative positions of each array element on the probe become unstable. This can lead to errors in the calculation of delays between arrays, ultimately preventing the reconstruction of a true image. To address this issue, the following solutions are currently available:

[0003] 1. After attaching the probe to the skin surface, a 3D camera is used to scan the probe's three-dimensional structure and infer the position of each array element. This method has the following problems: First, 3D scanning accuracy is low. For ultrasound beam synthesis, an array element position error exceeding half the wavelength of the sound wave (tens of microns) will have a significant impact. Currently available 3D scanners cannot achieve this accuracy or require high costs to achieve. In addition, a 3D scan takes a long time, and the flexible probe will change position after being attached to the body. If it is not recalibrated, the results will be affected, which is time-consuming and labor-intensive.

[0004] 2. Integrate a fiber optic sensor into the flexible probe to estimate the probe's bending degree based on light attenuation; or integrate a pressure sensor into the probe to infer probe deformation based on the probe material and strain-stress relationship. However, integrating either a fiber optic sensor or a pressure sensor into the flexible probe is costly and significantly increases the difficulty of flexible probe manufacturing. Furthermore, the integrated sensor itself can affect the transducer's vibration efficiency.

[0005] 3. Using deep learning methods, a model for estimating element positions is trained using a large amount of data containing real labels. However, even with a large number of training samples, deep learning cannot fully replicate real-world usage scenarios. This is because everyone's skin shape is unique, and the estimation model cannot be derived based on unknown data.

[0006] 4. Reduce the operating frequency of the flexible probe. When the wavelength of the sound wave is large, the distortion of the probe shape has less impact on beamforming. However, this method often ignores the impact of array element deformation on beamforming. Summary of the Invention

[0007] The purpose of this application is to provide an ultrasonic image correction method, device and medium for a flexible ultrasonic probe, which can achieve continuous adaptive calibration at low cost and avoid manual intervention.

[0008] To solve the above-mentioned technical problems, an embodiment of the present application provides, on the one hand, an ultrasonic image correction method for a flexible ultrasonic probe, comprising: based on a single-transmit-multiple-receive signal transmission and reception mode, the N array elements of the probe act as transmitting array elements in turn to transmit pulse sound waves, and all array elements receive echo signals at the same time to obtain an original radio frequency signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points; the correlation between channel signals is calculated based on the original radio frequency signal; a loss function is constructed based on the correlation, and the loss function includes a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term; the true position of the array element is estimated through gradient descent iterative calculation; and an ultrasonic image is reconstructed based on the estimated true position of the array element.

[0009] Optionally, the calculation formula for the correlation between the channel signals is:

[0010]

[0011] in, is the delay value of each channel signal calculated based on the spatial geometry.

[0012] Optionally, the loss function is:

[0013]

[0014] in is the element spacing constraint coefficient, is the image entropy constraint coefficient, is the array element position, is the entropy value of the original ultrasound image constructed according to the original position of the array elements.

[0015] Optionally, estimating the true position of the array element by gradient descent iterative calculation includes:

[0016] The Adam optimizer is used for iterative update optimization, and the iterative update formula is:

[0017]

[0018] in, is the array element position parameter, is the learning rate, is the array element position parameter after iterative update.

[0019] Optionally, reconstructing the ultrasonic image based on the estimated true position of the array element includes: for a point r(X, Z) in the imaging area, calculating the flight time of the sound wave from the true position of the transmitting array element to the true position of the receiving array element, and the flight time calculation formula is:

[0020]

[0021] in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound;

[0022] Based on the flight time, the signals of each channel are delayed and superimposed according to the following formula to obtain the reconstructed image information:

[0023] .

[0024] Optionally, the method further includes: calculating the transmission delay of each channel signal based on the estimated true position of the array element; focusing the array element according to the transmission delay, and collecting Doppler blood flow signals to achieve beam focusing.

[0025] Another aspect of the present application provides an ultrasonic image correction device for a flexible ultrasonic probe, which is applicable to the above-mentioned ultrasonic image correction method, including: an original radio frequency signal acquisition module: based on a single-transmit-multiple-receive signal transceiver mode, N array elements of the probe sequentially serve as transmitting array elements to transmit pulsed sound waves, and all array elements simultaneously receive echo signals to obtain an original radio frequency signal S(m,n,t), where m is a transmitting event, n is a receiving channel, and t is the number of fast time points; a correlation calculation module: used to calculate the correlation between channel signals based on the original radio frequency signal; a loss function construction module: used to construct a loss function based on the correlation, wherein the loss function includes a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term;

[0026] The array element true position estimation module is used to estimate the true position of the array element through gradient descent iterative calculation; the ultrasound image reconstruction module is used to reconstruct the ultrasound image based on the estimated true position of the array element.

[0027] Optionally, the ultrasound image reconstruction module includes: a flight time calculation module: for a point r(X, Z) in the imaging area, calculating the flight time of the sound wave from the actual position of the transmitting array element to the actual position of the receiving array element. The flight time calculation formula is:

[0028] in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound;

[0029] Ultrasonic image reconstruction submodule: Based on the flight time, the signals of each channel are delayed and superimposed according to the following formula to obtain the reconstructed image information: .

[0030] Optionally, the ultrasonic image correction device also includes: a transmission delay calculation module: used to calculate the transmission delay of each channel signal based on the estimated true position of the array element; a focused transmission module: used to focus the transmission of the array element according to the transmission delay, and collect Doppler blood flow signals to achieve beam focusing.

[0031] On the other hand, an embodiment of the present application provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above-mentioned ultrasound image correction method when executed by a processor.

[0032] Compared with the prior art, the embodiments of this application are

[0033] 1. The image correction algorithm is based on self-calibration of array element positions through echo signal feature extraction. Flexible strategies can be adopted to regularly update array element position parameters, enabling real-time tracking of array element parameters and continuous adaptive calibration, avoiding manual intervention.

[0034] 2. This ultrasound image correction method is based on pure software implementation, does not rely on external sensors or equipment, has low requirements for the flexible probe manufacturing process, and reduces the correction cost.

[0035] 3. Compared with deep learning methods, this method does not require the establishment of a large database to train the estimation model. Instead, it is optimized based on the current data, can adapt to different individual differences, and has high compatibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] One or more embodiments are exemplarily illustrated by pictures in the corresponding drawings. These exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as similar elements. Unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0037] Figure 1 is a flow chart of an ultrasonic image correction method according to one embodiment of the present application;

[0038] Figure 2 is a flow chart of an ultrasonic image correction method according to another embodiment of the present application;

[0039] Figure 3 is a schematic structural diagram of an ultrasonic image correction device according to an embodiment of the present application;

[0040] Figure 4is a schematic structural diagram of an ultrasonic image correction device according to another embodiment of the present application;

[0041] Figure 5 It is a structural schematic diagram of an ultrasonic image correction device according to another embodiment of the present application. DETAILED DESCRIPTION

[0042] The following describes the embodiments of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application 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 application. It should be noted that, in the absence of conflict, the features in the following embodiments and embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of this application.

[0043] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this application, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0044] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The illustrations only show components related to the present application 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 can be changed at will, and the component layout type may also be more complicated.

[0045] Additionally, in the following description, specific details are provided to provide a thorough understanding of the examples, however, one skilled in the art will appreciate that the examples can be practiced without these specific details.

[0046] Current medical ultrasound testing technology uses an ultrasound probe to transmit pulsed ultrasound waves into biological tissue. The sound waves scatter at the tissue interface, forming an echo signal. This echo signal is received by the probe and converted into an electrical signal for subsequent processing. Ultrasound probes utilize an array transducer design, consisting of dozens of precisely arranged transducer elements. Each element is equipped with an independent drive circuit. By precisely controlling the phase delay of each element's excitation timing, electronic focusing of the transmit and receive beams is achieved, and the energy of the acoustic wave signal is increased through signal superposition. This process is called array beamforming.

[0047] In beamforming, delay control accuracy directly determines signal quality, and delay calculation relies on the relative positions of array elements as parameters. Therefore, if the corresponding calculation parameters are not changed when the array element position changes, the calculated delay will be incorrect, and the sound waves will not be focused. When the flexible probe is attached to the human body surface, the array elements will undergo dynamic deformation. Since everyone's skin condition is different, the position of the array elements becomes an unknown variable. If the array element position parameters in the normal state are still used for beamforming, it will be difficult to achieve the desired effect. Therefore, it is necessary to optimize the array element position parameters so that the optimized array element position parameters are as close as possible to the actual array element position, thereby improving the accuracy of image reconstruction.

[0048] Based on this, an embodiment of the present application provides an ultrasonic image correction method for a flexible ultrasonic probe, such as Figure 1 As shown, the following steps are included:

[0049] In step 101, based on the single-transmit-multiple-receive signal transmission and reception mode, the N array elements of the probe act as transmitting array elements in turn to transmit pulse sound waves. All array elements simultaneously receive the echo signal to obtain the original RF signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points.

[0050] In the embodiment of the present application, the single-transmit multiple-receive signal transmission and reception mode is as follows: assuming that the probe has a total of N array elements, each array element will generate a transmission event, and the N array elements will have a total of N transmission events. In the first transmission event, array element 1 transmits a beam of pulsed sound waves, and then all N array elements participate in receiving the echo signal at the same time. Similarly, in the second transmission event, it is the turn of array element 2 to transmit sound waves, and all N array elements still participate in receiving the echo signal. And so on, when N transmission events are completed, it returns to the first transmission event and repeats the cycle. The advantage of using a single array element to transmit in sequence is that there is no need for physical focusing on the transmission, but only post-focusing in the receiving stage. In this step, N array elements transmit pulsed sound waves in sequence, and all array elements receive the echo signal at the same time. After amplification and filtering, the echo signal is sampled by the analog-to-digital converter as a radio frequency signal, thereby obtaining the initial radio frequency signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points.

[0051] In step 102, the correlation between channel signals is calculated based on the original RF signal to evaluate the accuracy of the original position of the array element. Specifically, assuming that the initial position of each array element is For a certain point in the imaging area , we need to calculate the flight time of the sound wave. The flight time can be calculated by dividing the flight distance by the speed of sound. The flight distance consists of two parts. The first part is the distance from the transmitting element to the point distance, use Refers to the second part from the point after reflection Back to the distance of the receiving element, use Refers to, the calculation formulas for the two are as follows:

[0052]

[0053]

[0054] in is the original position of the transmitting element, is the original position of the receiving element. Assume that the nth element is used to transmit in the nth transmission event, and all N elements participate in the reception in each event. The flight time can be calculated from the flight distance, and the flight time is the delay applied to the channel signal. :

[0055] (1)

[0056] For point For example, on each transmit event, each channel can get a delay .

[0057] Because echo signals from the same scattering point arrive at different array elements at different times, if the correct delay is applied to each channel signal (i.e., the delay corresponds to the actual array element position and the scattering point position), these delay-aligned signals should have a high degree of phase consistency (coherence), manifested as high cross-correlation values. Conversely, if the delay is incorrect (due to inaccurate position estimation), the correlation between the signals decreases. Therefore, the accuracy of the original array element position can be evaluated by the level of correlation between the signals. The formula for calculating the correlation between channel signals is:

[0058] (2)

[0059] in, is the received original RF signal, m is the transmit event, n is the receive channel, t is the number of fast time points, and τ is the delay value of each channel signal calculated based on spatial geometry. A larger value of C indicates a higher correlation between channel signals, which means a more accurate array element position. The reverse is also true. Therefore, embodiments of the present application can optimize array element position parameters by maximizing the correlation C between channels.

[0060] In step 103, a loss function is constructed based on the correlation. The loss function includes a channel signal correlation term, an element spacing constraint term, and an image entropy constraint term. Specifically, when constructing the loss function, the inter-channel correlation C can be negated. Assuming there are M transmission events, the total correlation coefficient is the sum of the correlation coefficients of all transmission events, that is:

[0061]

[0062] To prevent the optimization process from converging to non-physical parameter solutions and to maintain reasonable spacing and order between elements, it is necessary to introduce element spacing constraints into the loss function. The first term aims to impose a minimum spacing constraint between elements. This constraint calculates the sum of the Manhattan distances between all pairs of elements, multiplies it by a regularization coefficient, and then adds it to the loss function. The main consideration for using Manhattan distance is its piecewise linear property, which simplifies the calculation of the gradient of the loss function with respect to the optimization parameters:

[0063] The element spacing constraint can be expressed as:

[0064]

[0065] in is the element spacing constraint coefficient, It should be noted that in order to constrain the horizontal geometric order of the array elements and to ensure that the array elements are arranged strictly in order, the absolute value of the distance in the z direction is used in the above formula, while the distance in the x direction is not.

[0066] In addition, in order to maximize the richness of image information and avoid the optimization falling into local optimum, the embodiment of the present application also introduces an image entropy constraint term into the loss function. The image entropy constraint term can be expressed as:

[0067]

[0068] in is the image entropy constraint coefficient, To obtain the initial ultrasound image according to formula (1), X and Z are points on the image. It can be obtained according to the following formula:

[0069]

[0070] Therefore, the total loss function can be expressed as:

[0071] (3)

[0072] in is the array element position, is the entropy value of the original ultrasound image constructed according to the original position of the array element, 、 The specific value of can be determined according to experimental data, for example, by presetting different parameter combinations and taking image quality as the evaluation index to select the optimal parameter combination.

[0073] In step 104, the true position of the array element is estimated by gradient descent iterative calculation. Specifically, the Adam optimizer can be used for iterative update optimization, and the iterative update formula is:

[0074] (4)

[0075] in, is the array element position parameter (its initial parameter is set to the original position of the array element when the probe is in a flat state), is the array element position parameter after iterative update, is the learning rate, which can be adjusted adaptively. For example, a larger step size is used in the early stage of optimization to accelerate convergence, while the step size is automatically reduced in the later stage to achieve fine adjustment. The key to the above process is to calculate the loss function Opponent position The partial derivative of The calculation formula (3) is defined as a function and saved when defining Parameters When the partial derivative needs to be calculated, the partial derivative value corresponding to the specific parameter value is obtained by backpropagation, and then applied to the iterative update formula (4).

[0076] In this embodiment, The position parameters of the array elements obtained after iterative update calculation are applied in the next iterative update calculation. This cycle is repeated until the preset number of iterations is reached. The position parameters of the array elements obtained by the last iterative update calculation are used as the estimated true position of the array elements.

[0077] In step 105, the ultrasound image is reconstructed based on the estimated true position of the array element. Specifically, for a point r in the imaging area, the flight time of the sound wave from the true position of the transmitting array element to the true position of the receiving array element is calculated. The flight time calculation formula is:

[0078]

[0079] in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound;

[0080] Based on the flight time, the signals of each channel are delayed and superimposed according to the following formula to obtain reconstructed image information.

[0081]

[0082] It should be noted that the method of reconstructing the ultrasound image based on the estimated true position of the array element in this step is consistent with the method of constructing the original ultrasound image. The difference lies in the different position parameters of the array elements used. The original ultrasound image is constructed using the original position of the array element, while the ultrasound image reconstruction in this step uses the estimated true position of the array element.

[0083] In the embodiment of the present application, a true ultrasound image is reconstructed based on the estimated true position of the array elements. Then, envelope extraction, downsampling, scan conversion, and logarithmic compression are performed on the image intensity to obtain a calibrated B-mode image.

[0084] Compared with the prior art, the embodiments of the present application can correct the delay calculation error caused by probe deformation by evaluating the true position of the array element, avoid image blur or distortion, and thus reconstruct an accurate ultrasound image. Moreover, the ultrasound image correction method is based on pure software implementation, does not rely on external sensors or equipment, has low requirements for the flexible probe manufacturing process, and reduces the correction cost. The image correction algorithm is based on the self-calibration of the array element position through echo signal feature extraction. It can adopt a flexible strategy to regularly update the array element position parameters, realize real-time tracking of the array element parameters, and realize continuous adaptive calibration to avoid manual intervention. Compared with the deep learning method, this method does not need to establish a large database to train the prediction model, but optimizes according to the current data, can adapt to different human tissues, and has high compatibility.

[0085] In another embodiment, Figure 2 As shown in Figure 1 The embodiment shown in the figure is optimized in that, after estimating the true position of the array elements, the correct phase delay is applied between the array elements to maximize the acoustic wave energy at the focus and improve the Doppler signal strength. The specific process is as follows:

[0086] Steps 201-205 and Figure 1 Steps 101 to 105 in the illustrated embodiment are similar and will not be described in detail here.

[0087] In step 206, based on the estimated true position of the array element, the transmission delay of each channel signal is calculated. Specifically, the transmission delay of each channel signal is calculated as:

[0088]

[0089]

[0090] in is the estimated true array element position, is the focus position; is the flight time of the sound wave from the actual position of the array element to the focus; is the relative delay (minus the minimum delay to ensure all ≥0, to avoid negative delay).

[0091] In step 207, the array is focused and transmitted according to the transmission delay, and Doppler blood flow signals are collected to achieve beam focusing. Specifically, the focus position can be Set at the center of the blood vessel (can be pre-positioned by B-mode image or blood flow detection), and then each element is calculated according to the Delayed triggering allows all sound waves to reach the focal point simultaneously, achieving phase superposition. This increases the sound pressure at the focal point, concentrating the energy while dispersing the sound energy in non-focal areas, reducing interference.

[0092] This embodiment calculates the delay based on the optimized array element positions and blood vessel coordinates. By applying the correct phase delay between array elements, the acoustic wave energy at the focus can be maximized, the Doppler signal intensity can be improved, and high-resolution ultrasound imaging results can be obtained.

[0093] Based on the same inventive concept, this application also provides an ultrasonic image correction device for a flexible ultrasonic probe. It should be noted that the device illustrated below is an example of a device corresponding to one of the above-mentioned method embodiments. In other device embodiments, the configuration of the unit module functions and the number of modules can be configured accordingly based on the above-mentioned method embodiments.

[0094] like Figure 3 As shown, the ultrasonic image correction device includes: an original radio frequency signal acquisition module 1: based on a single-transmit multiple-receive signal transmission and reception mode, the N array elements of the probe act as transmitting array elements in turn to transmit pulse sound waves, and all array elements receive echo signals simultaneously to obtain the original radio frequency signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points;

[0095] Correlation calculation module 2: used to calculate the correlation between channel signals based on the original RF signal;

[0096] Loss function construction module 3: used to construct a loss function according to the correlation, wherein the loss function includes a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term;

[0097] Array element true position estimation module 4: used to estimate the true position of the array element through gradient descent iterative calculation;

[0098] Ultrasonic image reconstruction module 5: used to reconstruct the ultrasonic image according to the estimated true position of the array element.

[0099] Compared with the prior art, the embodiment of the present application is that the array element true position estimation module 4 evaluates the array element position to make it as close as possible to the array element true position, which can correct the delay calculation error caused by probe deformation and avoid image blur or distortion, so that the ultrasound image reconstruction module 5 can reconstruct an accurate ultrasound image based on the estimated array element true position. Each functional module is implemented based on pure software, without relying on external sensors or equipment, and has low requirements for the flexible probe manufacturing process, reducing the correction cost. The array element true position estimation module realizes self-calibration of the array element position based on the extraction of echo signal features. It can adopt a flexible strategy to regularly update the array element position parameters, realize real-time tracking of the array element parameters, and achieve continuous adaptive calibration to avoid manual intervention. This device does not need to establish a large database to train the prediction model, but optimizes it according to the current data. It can cope with different human tissues and adapt to different individual differences, and has high compatibility.

[0100] In an alternative embodiment, if Figure 4 As shown, the ultrasound image reconstruction module 5 includes:

[0101] The flight time calculation module 51 is used to calculate the flight time of the acoustic wave from the actual position of the transmitting array element to the actual position of the receiving array element for a point r(X,Z) in the imaging area. The flight time calculation formula is:

[0102]

[0103] in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound;

[0104] The ultrasound image reconstruction submodule 52 is used to delay and superimpose the signals of each channel based on the flight time according to the following formula to obtain reconstructed image information:

[0105] .

[0106] The embodiment of the present application provides a specific implementation method for ultrasonic image reconstruction. The ultrasonic image reconstruction module 5 performs ultrasonic image reconstruction based on the estimated true position of the array element, effectively correcting the delay calculation error caused by the deformation of the array element position, thereby reconstructing an accurate ultrasonic image.

[0107] In another alternative embodiment, if Figure 5 As shown, the ultrasonic image correction device also includes:

[0108] Transmission delay calculation module 6: used to calculate the transmission delay of each channel signal based on the estimated true position of the array element;

[0109] Focused transmission module 7: used for focusing the transmission of the array element according to the transmission delay, and collecting Doppler blood flow signals to achieve beam focusing.

[0110] In this embodiment, the transmission delay calculation module 6 calculates the delay based on the optimized array element position and blood vessel coordinates, and applies the correct phase delay between the array elements through the focusing transmission module 7, which can maximize the sound wave energy at the focus and enhance the Doppler signal intensity, thereby obtaining high-resolution ultrasound imaging results.

[0111] An embodiment of the present application further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the steps of the ultrasonic image correction method described in any embodiment of the present application are implemented.

[0112] It should be noted that the computer storage medium may include, but is not limited to, a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device, or any suitable combination thereof. In a possible embodiment, the present invention may also provide a method of implementing data processing in the form of a program product, which includes program code. When the program product is executed on a terminal device, the program code is used to cause the terminal device to perform several steps of the method described in any of the aforementioned embodiments.

[0113] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

[0115] Those skilled in the art will appreciate that the above embodiments are specific embodiments for implementing the present invention, and that in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A method for correcting ultrasonic images using a flexible ultrasonic probe, characterized in that: include: Based on the single-transmit multiple-receive signal transmission and reception mode, the N array elements of the probe act as transmitting array elements to transmit pulse sound waves in turn. All array elements receive the echo signal simultaneously, and the original RF signal S(m,n,t) is obtained, where m is the transmission event, n is the receiving channel, and t is the number of fast time points. Calculating the correlation between channel signals according to the original radio frequency signal; Constructing a loss function according to the correlation, wherein the loss function includes a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term; Estimate the true position of the array element through gradient descent iterative calculation; Ultrasound image reconstruction is performed based on the estimated true position of the array elements.

2. The ultrasonic image correction method according to claim 1, characterized in that: The calculation formula for the correlation between the channel signals is: Among them, S(*) is the original RF signal received, is the delay value of each channel signal calculated based on the spatial geometry.

3. The ultrasonic image correction method according to claim 2, characterized in that: The loss function is: in is the element spacing constraint coefficient, is the image entropy constraint coefficient, is the array element position, is the entropy value of the original ultrasound image constructed according to the original position of the array element, and M is the total number of transmission events.

4. The ultrasonic image correction method according to claim 3, characterized in that: The estimating the true position of the array element by gradient descent iterative calculation includes: The Adam optimizer is used for iterative update optimization, and the iterative update formula is: in is the array element position parameter, is the learning rate, is the array element position parameter after iterative update.

5. The ultrasonic image correction method according to claim 1, characterized in that: The reconstructing of the ultrasonic image according to the estimated true position of the array element includes: For a point r(X,Z) in the imaging area, calculate the flight time of the acoustic wave from the true position of the transmitting array element to the true position of the receiving array element. The flight time calculation formula is: in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound; Based on the flight time according to the formula The signals of each channel are delayed and superimposed to obtain the reconstructed image information.

6. The ultrasonic image correction method according to claim 1, characterized in that: The method further comprises: Based on the estimated true position of the array element, the transmission delay of each channel signal is calculated; The array element is focused and transmitted according to the transmission delay, and Doppler blood flow signals are collected to achieve beam focusing.

7. An ultrasonic image correction device for a flexible ultrasonic probe, applied to the ultrasonic image correction method according to any one of claims 1 to 6, characterized in that: include: Original RF signal acquisition module: Based on the single-transmit multiple-receive signal transmission and reception mode, the probe's N array elements act as transmitting array elements in turn to transmit pulse sound waves. All array elements receive the echo signal simultaneously to obtain the original RF signal S(m,n,t), where m is the transmission event, n is the receiving channel, and t is the number of fast time points; Correlation calculation module: used to calculate the correlation between channel signals based on the original radio frequency signal; A loss function construction module is used to construct a loss function according to the correlation, wherein the loss function includes a channel signal correlation term, an array element spacing constraint term, and an image entropy constraint term; Array element true position estimation module: used to estimate the true position of the array element through gradient descent iterative calculation; Ultrasonic image reconstruction module: used to reconstruct ultrasonic images based on the estimated true positions of array elements.

8. The ultrasonic image correction device according to claim 7, characterized in that: The ultrasound image reconstruction module includes: Flight time calculation module: For a point r(X,Z) in the imaging area, the flight time of the acoustic wave from the actual position of the transmitting array element to the actual position of the receiving array element is calculated. The flight time calculation formula is: in is the distance from the true position of the transmitting element to point r, is the distance from point r to the actual position of the receiving array element, and c is the speed of sound; Ultrasound image reconstruction submodule: Based on the flight time according to the formula: The signals of each channel are delayed and superimposed to obtain the reconstructed image information.

9. The ultrasonic image correction device according to claim 7, characterized in that: The ultrasonic image correction device further includes: Transmit delay calculation module: used to calculate the transmit delay of each channel signal based on the estimated true position of the array element; Focused transmission module: used for focusing the transmission of the array element according to the transmission delay, and collecting Doppler blood flow signals to achieve beam focusing.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the ultrasonic image correction method according to any one of claims 1 to 6 are implemented.

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