Blood flow velocity determination method, apparatus, and computer device

Abstract

The application relates to a blood flow velocity determination method, device and computer equipment. The method comprises the following steps: acquiring a blood flow velocity calibration angle when blood flow velocity ultrasonic detection is performed on a target object; calibrating an ultrasonic echo signal corresponding to the target object according to the blood flow velocity calibration angle to obtain a calibrated echo signal; and determining a blood flow velocity image of the target object according to the calibrated echo signal. The method can improve the correction accuracy of tissue movement or blood flow velocity in Doppler ultrasonic detection from the Doppler principle itself, and reduce the difference between the tissue velocity detection result and the actual tissue velocity of the target object.

Description

Technical Field

[0001] This application relates to the field of medical data processing technology, and in particular to a method, apparatus, computer equipment, storage medium, and computer program product for determining blood flow velocity. Background Technology

[0002] Medical Doppler ultrasound technology is primarily used for detecting tissue velocity in target objects, making its accuracy paramount. Current medical Doppler velocimetry achieves velocity calibration by adjusting the calibration angle. The calibration angle refers to the angle between the direction of the main emitted ultrasound beam and the direction of blood flow. In most cases, a simple calibration angle can accurately measure velocity. However, when there is a significant difference between the main emitted beam and the directions of the various receiving elements, or when the main emitted beam is inconsistent with the direction of the sound field vector, simple correction of the calibration angle is insufficient, leading to a large discrepancy between the detected tissue velocity and the actual tissue velocity. Summary of the Invention

[0003] Therefore, it is necessary to provide a method, apparatus, computer device, computer-readable storage medium, and computer program product for determining blood flow velocity that can reduce the difference between the detected tissue velocity and the actual tissue velocity in the target object, in order to address the above-mentioned technical problems.

[0004] In a first aspect, this application provides a method for determining blood flow velocity. The method includes: acquiring a blood flow velocity calibration angle during ultrasound detection of blood flow velocity on a target object; calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain a calibration echo signal; and determining a blood flow velocity image of the target object based on the calibration echo signal.

[0005] Secondly, this application also provides a blood flow velocity determination device. The device includes: a data acquisition module for acquiring a blood flow velocity calibration angle during ultrasound detection of a target object; a data calibration module for calibrating the ultrasound echo signal based on the blood flow velocity calibration angle to obtain a calibration echo signal; and a velocity measurement module for determining a blood flow velocity image of the target object based on the calibration echo signal.

[0006] Thirdly, this application also provides a computer device. The computer device includes a memory and a processor. The memory stores a computer program, and the processor, when executing the computer program, performs the following steps: acquiring a blood flow velocity calibration angle during ultrasound detection of a target object; calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain a calibration echo signal; and determining a blood flow velocity image of the target object based on the calibration echo signal.

[0007] Fourthly, this application also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program thereon, which, when executed by a processor, performs the following steps: acquiring a blood flow velocity calibration angle during ultrasound detection of a target object; calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain a calibration echo signal; and determining a blood flow velocity image of the target object based on the calibration echo signal.

[0008] Fifthly, this application also provides a computer program product. The computer program product includes a computer program that, when executed by a processor, performs the following steps: acquiring a blood flow velocity calibration angle during ultrasound detection of a target object; calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain a calibration echo signal; and determining a blood flow velocity image of the target object based on the calibration echo signal.

[0009] The aforementioned method, apparatus, computer equipment, storage medium, and computer program product for determining blood flow velocity involve: acquiring a blood flow velocity calibration angle during ultrasound detection of a target object; calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain a calibration echo signal; and determining a blood flow velocity image of the target object based on the calibration echo signal.

[0010] By converting the mechanical vibration of blood flow velocity ultrasound detection into multi-channel (multi-element) electrical signals, and obtaining the blood flow velocity calibration angle from the multi-channel (multi-element) electrical signals, and then calibrating the ultrasound echo signal of blood flow velocity ultrasound detection based on the Doppler principle and the blood flow velocity calibration angle, a blood flow velocity image of the target object can be obtained. This approach improves the accuracy of Doppler ultrasound detection in correcting tissue motion or blood flow velocity based on the Doppler principle itself, and reduces the difference between the detected tissue velocity and the actual tissue velocity in the target object. Attached Figure Description

[0011] Figure 1 This is a diagram illustrating the application environment of a blood flow velocity determination method in one embodiment.

[0012] Figure 2 This is a flowchart illustrating a method for determining blood flow velocity in one embodiment;

[0013] Figure 3 This is a flowchart illustrating a method for obtaining calibration echo signals in one embodiment;

[0014] Figure 4 This is a flowchart illustrating a method for obtaining calibration echo signals in another embodiment;

[0015] Figure 5 This is a flowchart illustrating a method for extracting frequency points in the frequency domain of an echo signal in one embodiment.

[0016] Figure 6 This is a flowchart illustrating a method for obtaining the echo signal frequency adjustment point in one embodiment;

[0017] Figure 7 This is a flowchart illustrating a method for obtaining calibration echo signals in one embodiment;

[0018] Figure 8 This is a flowchart illustrating a method for obtaining blood flow velocity images in one embodiment;

[0019] Figure 9 This is a flowchart illustrating a method for obtaining pulsed Doppler images in one embodiment;

[0020] Figure 10 Here is a schematic diagram of the sound wave focusing vector in one embodiment;

[0021] Figure 11 This is a schematic diagram of the process of obtaining a pulsed Doppler image in one embodiment;

[0022] Figure 12 This is a structural block diagram of a blood flow velocity determination device in one embodiment;

[0023] Figure 13 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0025] The blood flow velocity determination method provided in this application embodiment can be applied to, for example... Figure 1In the application environment shown, terminal 102 communicates with server 104 via a network. A data storage system can store the data that server 104 needs to process. The data storage system can be integrated onto server 104 or placed in the cloud or on another network server. Server 104 obtains the blood flow velocity calibration angle from terminal 102 during ultrasound detection of the target object; based on the blood flow velocity calibration angle, it calibrates the ultrasound echo signal corresponding to the target object to obtain a calibration echo signal; and determines the blood flow velocity image of the target object based on the calibration echo signal. Terminal 102 can be, but is not limited to, various IoT devices and portable wearable devices. Server 104 can be implemented using a standalone server or a server cluster consisting of multiple servers.

[0026] In one embodiment, such as Figure 2 As shown, a method for determining blood flow velocity is provided, which can be applied to... Figure 1 Taking the server in the example, the following steps are included:

[0027] Step 202: Obtain the blood flow velocity calibration angle when performing ultrasound detection on the target object.

[0028] The target object can be a person or an animal, and the target object contains a region of interest, such as blood vessels in the head and neck, blood vessels in the heart, and blood vessels in the lower limbs.

[0029] Among them, blood flow velocity ultrasound detection can be carried out by using an ultrasound imaging device to emit ultrasound waves to the region of interest in the target object in order to obtain some parameters for calculating blood flow velocity in the region of interest.

[0030] The blood flow velocity calibration angle can be the angle between the line connecting the center of the receiving array element and the mass point and the direction of mass point movement, expressed as θ. j This is represented as follows. The receiving element is the device that transmits and receives signals in the ultrasound imaging equipment, while the particle is a moving particle (blood cell), such as... Figure 10 The black dots in the blood vessels shown are obtained by using methods such as... Figure 10 P in i express.

[0031] Specifically, ultrasound imaging equipment is used to perform ultrasound detection of blood flow velocity on a target object. When the ultrasound probe of the ultrasound imaging equipment moves near the region of interest, the operating mode of the ultrasound imaging equipment can be switched between single-modal imaging and multi-modal imaging based on the blood flow velocity detection requirements of the region of interest. Based on the determined imaging mode operation, the ultrasound imaging equipment emits ultrasound waves towards the region of interest at a fixed or varying pulse repetition frequency to obtain ultrasound echo signals and blood flow velocity calibration angles.

[0032] Step 204: Based on the blood flow velocity calibration angle, calibrate the ultrasound echo signal corresponding to the target object to obtain the calibrated echo signal.

[0033] Among them, the ultrasonic echo signal can be a signal generated when an ultrasonic probe incident sound waves into the object being measured, producing an echo that is then received by the probe.

[0034] The calibration echo signal can be the signal obtained by calibrating the ultrasound echo signal using the blood flow velocity calibration angle.

[0035] Specifically, based on the operation of the ultrasound imaging equipment in a determined imaging mode, ultrasound waves are emitted towards the region of interest at a fixed or varying pulse repetition frequency. Simultaneously, the ultrasound probe of the ultrasound imaging equipment acquires the blood flow velocity detection angle. Combining the blood flow velocity detection angle and the blood flow velocity calibration angle, the ultrasound echo signal (Δf) from the Doppler ultrasound channel is used to... j The center frequency (f) of the emitted ultrasonic wave. c As a constraint, the Doppler ultrasound channel signal of the ultrasound echo signal is calibrated to obtain the calibrated echo signal.

[0036] Step 206: Determine the blood flow velocity image of the target object based on the calibration echo signal.

[0037] Among them, blood flow velocity images can be images that show the flow velocity of moving particles (blood cells) in blood vessels.

[0038] Specifically, since the ultrasound imaging equipment has multiple Doppler ultrasound channels, and each channel uses a blood flow velocity detection angle and a blood flow velocity calibration angle to calibrate the ultrasound echo signal, a calibrated echo signal is obtained. Therefore, beamforming is performed on the individual calibrated echo signals, i.e., the appropriate superposition of the calibrated echo signals, to obtain a composite echo signal. This composite echo signal is then used as the input signal for pulse Doppler link processing. Finally, through pulse Doppler link processing, the blood flow velocity image of the target object can be obtained. The principle formula for generating the blood flow velocity value of the target object's blood flow velocity image is as follows:

[0039]

[0040] Where, Δf j It is the ultrasound echo signal measured by the ultrasound probe, θ is the blood flow velocity detection angle, and f c θ is the center frequency of the sound wave that emits ultrasound. j The calibration angle is for blood flow velocity, where c is the speed at which ultrasound waves propagate within the human body.

[0041] In the above-mentioned method for determining blood flow velocity, the blood flow velocity calibration angle is obtained when performing ultrasound detection on the target object; the ultrasound echo signal corresponding to the target object is calibrated according to the blood flow velocity calibration angle to obtain a calibration echo signal; and the blood flow velocity image of the target object is determined according to the calibration echo signal.

[0042] By converting the mechanical vibration of blood flow velocity ultrasound detection into multi-channel (multi-element) electrical signals, and obtaining the blood flow velocity calibration angle from the multi-channel (multi-element) electrical signals, and then calibrating the ultrasound echo signal of blood flow velocity ultrasound detection based on the Doppler principle and the blood flow velocity calibration angle, a blood flow velocity image of the target object can be obtained. This approach improves the accuracy of Doppler ultrasound detection in correcting tissue motion or blood flow velocity based on the Doppler principle itself, and reduces the difference between the detected tissue velocity and the actual tissue velocity in the target object.

[0043] In one embodiment, such as Figure 3 As shown, the step of calibrating the ultrasound echo signal corresponding to the target object based on the blood flow velocity calibration angle to obtain the calibrated echo signal includes:

[0044] Step 302: Obtain the blood flow velocity detection angle when performing ultrasound detection on the target object.

[0045] The blood flow velocity detection angle can be the angle between the direction of the composite vector of the emitted sound field and the direction of motion of the particle. The blood flow velocity detection angle is determined using methods such as... Figure 10 In the figure, θ represents the direction of the particle composition vector, while the direction of the particle composition vector is represented by, for example, θ represents the direction of the particle composition vector. Figure 10 In express.

[0046] Specifically, based on the operation of the ultrasound imaging device in a determined imaging mode, ultrasound waves are emitted towards the region of interest at a fixed or varying pulse repetition frequency. Simultaneously, the ultrasound probe of the device is used to acquire blood flow velocity and the direction vector of the line connecting the center of each probe element to the mass point, such as... Figure 10 In The expression is: The sum of vectors is... Furthermore, using The angle between the direction of motion of the particle and the direction of motion is used as the angle for detecting blood flow velocity.

[0047] Step 304: Demodulate the ultrasonic echo signal according to the center frequency of the emitted ultrasonic wave to obtain the demodulated echo signal.

[0048] The center frequency of the emitted ultrasonic wave can be the frequency with the strongest energy of the ultrasonic echo signal in the Doppler ultrasonic channel. In practical applications, since the ultrasonic echo signal often contains multiple components of different frequencies, it needs to be adjusted and then filtered to extract the desired information. The design and selection of the filter must be determined based on the center frequency of the emitted ultrasonic wave, and it is usually a low-pass filter.

[0049] The demodulated echo signal can be an electrical signal obtained by demodulating the ultrasonic echo signal.

[0050] Specifically, taking any Doppler ultrasound channel as an example, the center frequency (f) of the emitted ultrasound wave... c As a constraint, the ultrasound echo signal obtained from the ultrasound detection of blood flow velocity through the Doppler ultrasound channel is demodulated to obtain the demodulated electrical signal, i.e., the demodulated echo signal d(t). Methods for demodulating the ultrasound echo signal include coherent demodulation, incoherent demodulation, phase-shifting demodulation, and nonlinear demodulation. For different blood flow velocities detected by ultrasound, one or more demodulation methods can be selected.

[0051] Step 306: Based on the blood flow velocity detection angle and the blood flow velocity calibration angle, calibrate the demodulated echo signal to obtain the calibrated echo signal.

[0052] Specifically, the frequency domain of the modulated echo signal corresponding to the demodulated echo signal is calculated by means of signal domain transformation, wherein the signal domain transformation can be Fourier transform (FFT). Combining the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency points of the echo signal in the frequency domain of the modulated echo signal are calibrated to obtain the calibrated frequency points of the echo signal. Finally, the frequency domain of the modulated echo signal composed of the calibrated frequency points of the echo signal is subjected to inverse signal domain transformation, namely inverse Fourier transform (IFFT), to obtain the calibrated time domain echo signal as the calibration echo signal.

[0053] In this embodiment, by using the blood flow velocity detection angle and the blood flow velocity calibration angle, the demodulated echo signal obtained by mediation is calibrated, which can ensure the accuracy and reliability of the calibration echo signal and improve the accuracy of subsequent calculation of blood flow velocity images.

[0054] In one embodiment, such as Figure 4 As shown, the step of calibrating the demodulated echo signal based on the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain the calibrated echo signal includes:

[0055] Step 402: Perform signal domain transformation on the demodulated echo signal to determine the frequency points of each echo signal in the frequency domain.

[0056] Among them, the signal domain transformation can be the Fourier transform (FFT).

[0057] Among them, the frequency points in the frequency domain of the echo signal can be any frequency points in the frequency domain obtained after the demodulated echo signal is subjected to Fourier transform.

[0058] Specifically, the demodulated echo signal is transformed in the signal domain, that is, the demodulated echo signal is transformed using Fourier transform to convert the demodulated echo signal into the frequency domain of the modulated echo signal. The frequency domain of the modulated echo signal includes components of different frequencies. In other words, the frequency domain of the modulated echo signal includes various frequency points of the echo signal, and the frequency of each frequency point of the echo signal is different.

[0059] Step 404: Adjust the frequency points of each echo signal according to the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain the frequency adjustment points of each echo signal.

[0060] The echo signal frequency adjustment point can be the frequency point after the echo signal frequency domain frequency point has been calibrated.

[0061] Specifically, based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency values ​​of each echo signal frequency point are adjusted, but the amplitude of each echo signal frequency point remains unchanged during the adjustment process, thus obtaining the echo signal frequency adjustment point.

[0062] Step 406: Perform inverse signal domain transformation on each of the echo signal frequency adjustment points to obtain the calibration echo signal.

[0063] Among them, the inverse signal domain transform can be the inverse Fourier transform (IFFT).

[0064] Specifically, for each echo signal frequency adjustment point, based on the application requirements and accuracy requirements of the calibration echo signal, a function is constructed to estimate the numerical values ​​of the positions between these echo signal frequency adjustment points, resulting in a new calibrated echo signal frequency domain. The time interval of each frequency point in the new calibrated echo signal frequency domain is still maintained in the time domain. Furthermore, an inverse signal domain transformation is performed on the new calibrated echo signal frequency domain, that is, the inverse Fourier transform is used to convert the new calibrated echo signal frequency domain into a calibration echo signal.

[0065] In this embodiment, by adjusting the frequency of the echo signal frequency point in the frequency domain using the blood flow velocity detection angle and the blood flow velocity calibration angle, the accuracy of subsequent blood flow velocity image measurement can be ensured, and measurement errors in the blood flow velocity image due to frequency deviation can be avoided.

[0066] In one embodiment, such as Figure 5 As shown, the step of performing signal domain transformation on the demodulated echo signal to determine the frequency points of each echo signal includes:

[0067] Step 502: Perform signal domain transformation on the demodulated echo signal to obtain the frequency domain of the initial modulated echo signal.

[0068] The frequency domain of the initial modulated echo signal can be the frequency domain obtained by performing a Fourier transform on the demodulated echo signal.

[0069] Specifically, the demodulated echo signal is transformed into the signal domain, that is, the demodulated echo signal is transformed into the Fourier transform to obtain the frequency domain of the initial modulated echo signal. The frequency domain of the initial modulated echo signal is represented by D(f), and the frequency domain range of the initial modulated echo signal frequency domain D(f) is [-f0, f0].

[0070] Step 504: Based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency domain of the initial modulated echo signal is extended to obtain the extended modulated echo signal frequency domain.

[0071] Among them, the extended frequency domain of the modulated echo signal can be the frequency domain obtained by extending the frequency domain range of the initial modulated echo signal frequency domain.

[0072] Specifically, based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency domain expansion amount for extending the initial modulation echo signal frequency domain is calculated. The initial modulation echo signal frequency domain is then expanded according to this expansion amount to obtain the extended modulation echo signal frequency domain. Since the frequency domain range of the initial modulation echo signal frequency domain D(f) is [-f0, f0], the extended modulation echo signal frequency domain is expressed by the following formula.

[0073]

[0074] Step 506: Extract the frequency points of each echo signal from the frequency domain of the extended adjusted echo signal.

[0075] Specifically, the frequency values ​​in the frequency domain of the extended and adjusted echo signal are traversed to obtain the frequency value traversal result. Based on the frequency value traversal result, the frequency points of each echo signal frequency domain are extracted from the extended and adjusted echo signal frequency domain. That is, the original frequency points are selected as the corresponding echo signal frequency domain frequency points in each extended frequency range (within the frequency domain).

[0076] In this embodiment, by using the blood flow velocity detection angle and the blood flow velocity calibration angle to extend the frequency domain of the adjustment echo signal, the error introduced by the inaccurate correction angle can be improved. At the same time, it can enhance specific frequency components of the signal, which is beneficial to improving the clarity and contrast of subsequent imaging results. It can also make some signal features hidden in low amplitude frequency components more prominent, which helps to detect signal changes under abnormal or specific conditions.

[0077] In one embodiment, such as Figure 6 As shown, the step of adjusting the frequency points of each echo signal based on the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain the frequency adjustment points of each echo signal includes:

[0078] Step 602: Determine the echo signal frequency adjustment value based on the blood flow velocity detection angle and the blood flow velocity calibration angle.

[0079] The echo signal frequency adjustment value can be a numerical value used to adjust the frequency of a frequency point in the frequency domain of the echo signal.

[0080] Specifically, based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the echo signal frequency adjustment value is calculated to adjust the frequency value at each echo signal frequency point in the frequency domain. The expression for the echo signal frequency adjustment value is as follows.

[0081]

[0082] Step 604: Using the amplitude of each echo signal frequency point as a constraint, adjust each echo signal frequency point according to the echo signal frequency adjustment value to obtain each echo signal frequency adjustment point.

[0083] The amplitude can be the frequency domain value of the Fourier transform of the time domain signal.

[0084] Specifically, while ensuring that the amplitude of each echo signal frequency point in the extended adjustment echo signal frequency domain remains unchanged, each echo signal frequency point within the frequency range of the extended adjustment echo signal frequency domain is multiplied by the echo signal frequency adjustment value to obtain each echo signal frequency adjustment point. The specific expression is as follows.

[0085]

[0086] In this embodiment, by adjusting the frequency points of the echo signal using the blood flow velocity detection angle and the blood flow velocity calibration angle, while limiting the amplitude of the frequency points in the frequency domain of the echo signal, the frequency points in the frequency domain of the echo signal can be adjusted. This makes the signal more sensitive to information within a specific frequency range and improves the measurement accuracy of the blood flow velocity image.

[0087] In one embodiment, such as Figure 7 As shown, the step of performing inverse signal domain transformation on each of the echo signal frequency adjustment points to obtain the calibration echo signal includes:

[0088] Step 702: Perform interpolation processing on each of the echo signal frequency adjustment points to obtain the frequency domain of the interpolated adjusted echo signal.

[0089] The frequency domain of the interpolated adjusted echo signal can be the frequency domain obtained by interpolation processing of the extended adjusted echo signal frequency domain.

[0090] Specifically, a new frequency domain for the adjusted echo signal is constructed based on each echo signal frequency adjustment point. The new frequency domain for the adjusted echo signal can be expressed by the following expression.

[0091]

[0092] To ensure that the calibrated echo signal retains its original time intervals at each frequency point in the time domain, it is necessary to solve for D(f). i ).because Given that the interpolation is linear or polynomial, for D(f) i Interpolation processing is performed to obtain the frequency domain of the interpolated adjusted echo signal. To express.

[0093] Step 704: Perform inverse signal domain transformation on the frequency domain of the interpolated echo signal to obtain the calibration echo signal.

[0094] Specifically, an inverse signal domain transformation is performed on the frequency domain of the interpolated echo signal, that is, the frequency domain of the interpolated echo signal is transformed. Perform an inverse Fourier transform (IFFT) to obtain the calibration echo signal.

[0095] In this embodiment, by interpolating the results obtained from the frequency adjustment points of the echo signal and then performing inverse signal domain transformation, more data points can be added to the frequency adjustment points of the echo signal to increase the resolution. This allows for a more accurate determination of frequency changes in the frequency domain of the interpolated echo signal, resulting in better signal analysis and the acquisition of more accurate blood flow velocity images.

[0096] In one embodiment, such as Figure 8 As shown, determining the blood flow velocity image of the target object based on the calibration echo signal includes:

[0097] Step 802: Obtain the calibration echo signal corresponding to each Doppler ultrasound channel.

[0098] Among them, the Doppler ultrasound channel can be the ultrasound information receiving channel on the ultrasound imaging equipment.

[0099] Specifically, after performing ultrasound detection of blood flow velocity in the region of interest of the target object, the ultrasound echo signals of each Doppler ultrasound channel were calibrated using the blood flow velocity calibration angle to obtain the calibrated echo signals corresponding to each Doppler ultrasound channel.

[0100] Step 804: Beamforming the calibration echo signals to obtain the synthesized echo signals.

[0101] The synthesized echo signal can be a signal obtained by weighted synthesis of multiple calibration echo signals.

[0102] Specifically, for each calibration echo signal, the beam weight of each Doppler ultrasound channel is calculated with the desired beam direction (i.e., the direction to be enhanced). Further, the calibration echo signal of each Doppler ultrasound channel is multiplied by the corresponding beam weight, and they are weighted and summed to generate a synthetic echo signal.

[0103] Step 806: Perform pulse Doppler link processing on the synthesized echo signal to obtain the blood flow velocity image of the target object.

[0104] Among them, pulse Doppler link processing can be a method for users to analyze and process hemodynamic information.

[0105] Specifically, the synthesized echo signal is used as the input signal for pulse Doppler link processing. By analyzing the frequency changes in the synthesized echo signal, the signal spectrum of blood flow from different velocities is calculated. Furthermore, spectral analysis is performed on the signal spectrum of blood flow from different velocities to obtain the blood flow velocity image of the target object. The blood flow velocity image includes the blood flow velocity value calculated by the blood flow velocity value principle formula.

[0106] In this embodiment, by performing beamforming on each calibration echo signal and then processing it with a pulse Doppler link, more comprehensive and accurate information can be obtained from the blood flow velocity image, thereby improving the measurement accuracy of the blood flow velocity image.

[0107] In one embodiment, such as Figure 9 As shown, after the step of determining the blood flow velocity image of the target object based on the calibration echo signal, the method further includes:

[0108] Step 902: Sample the blood flow velocity image according to a preset time interval to obtain a blood flow velocity sampling data set.

[0109] The preset time interval can be the interval between two samplings of the blood flow velocity image, which is the blood flow velocity image sampling period.

[0110] The blood flow velocity sampling data set can be a collection of data from multiple blood flow velocity images.

[0111] Specifically, since the blood flow velocity in the blood vessels is constantly changing, the server 104 samples the blood flow velocity image from the continuous blood flow velocity image according to a preset time interval to obtain a blood flow velocity sampling data set.

[0112] Step 904: Visualize the blood flow velocity sampling data set to obtain a pulsed Doppler image.

[0113] Among them, pulsed Doppler images can be images obtained by Doppler ultrasound detection.

[0114] Specifically, the blood flow velocity sampling data set is transformed according to the visualization requirements of a spectral image to obtain a blood flow velocity spectral image; and the blood flow velocity sampling data set is transformed according to a velocity-time variation image to obtain a blood flow velocity-time relationship image, i.e., a pulse Doppler image. For the processing flow of generating pulse Doppler images, please refer to... Figure 11 A schematic diagram of the process for obtaining the corresponding pulse Doppler image.

[0115] In this embodiment, by sampling blood flow velocity images at preset time intervals and visualizing them, it is possible to dynamically monitor blood flow changes and assess blood flow velocity distribution, more accurately analyze hemodynamic characteristics, and provide more accurate information for the detection of target objects.

[0116] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0117] Based on the same inventive concept, this application also provides a blood flow velocity determination device for implementing the blood flow velocity determination method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations of one or more blood flow velocity determination device embodiments provided below can be found in the limitations of a blood flow velocity determination method described above, and will not be repeated here.

[0118] In one embodiment, such as Figure 12 As shown, a blood flow velocity determination device is provided, comprising: a data acquisition module 1202, a data calibration module 1204, and a velocity measurement module 1206, wherein:

[0119] The data acquisition module 1202 is used to acquire the blood flow velocity calibration angle when performing ultrasound detection of blood flow velocity on the target object;

[0120] Data calibration module 1204 is used to calibrate the ultrasound echo signal according to the blood flow velocity calibration angle to obtain a calibrated echo signal;

[0121] The velocity measurement module 1206 is used to determine the blood flow velocity image of the target object based on the calibration echo signal.

[0122] In one embodiment, the data calibration module 1204 is further configured to acquire the blood flow velocity detection angle when performing ultrasound detection on the target object; demodulate the ultrasound echo signal according to the center frequency of the emitted ultrasound wave to obtain a demodulated echo signal; and calibrate the demodulated echo signal according to the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain a calibrated echo signal.

[0123] In one embodiment, the data calibration module 1204 is further configured to perform signal domain transformation on the demodulated echo signal to determine the frequency points of each echo signal in the frequency domain; adjust the frequency points of each echo signal in the frequency domain according to the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain the frequency adjustment points of each echo signal; and perform inverse signal domain transformation on each frequency adjustment point of the echo signal to obtain the calibration echo signal.

[0124] In one embodiment, the data calibration module 1204 is further configured to perform signal domain transformation on the demodulated echo signal to obtain an initial regulated echo signal frequency domain; expand the initial regulated echo signal frequency domain according to the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain an expanded regulated echo signal frequency domain; and extract each echo signal frequency point from the expanded regulated echo signal frequency domain.

[0125] In one embodiment, the data calibration module 1204 is further configured to determine the echo signal frequency adjustment value based on the blood flow velocity detection angle and the blood flow velocity calibration angle; and to adjust each echo signal frequency point according to the echo signal frequency adjustment value, using the amplitude of each echo signal frequency point as a constraint condition, to obtain each echo signal frequency adjustment point.

[0126] In one embodiment, the data calibration module 1204 is further configured to perform interpolation processing on each of the echo signal frequency adjustment points to obtain the frequency domain of the interpolated adjusted echo signal; and to perform inverse signal domain transformation on the frequency domain of the interpolated adjusted echo signal to obtain the calibration echo signal.

[0127] In one embodiment, the velocity measurement module 1206 is further configured to acquire the calibration echo signal corresponding to each Doppler ultrasound channel; perform beamforming on each calibration echo signal to obtain a synthesized echo signal; and perform pulse Doppler link processing on the synthesized echo signal to obtain a blood flow velocity image of the target object.

[0128] In one embodiment, the velocity measurement module 1206 is further configured to sample the blood flow velocity image according to a preset time interval to obtain a blood flow velocity sampling data set; and to visualize the blood flow velocity sampling data set to obtain a pulse Doppler image.

[0129] The various modules in the aforementioned blood flow velocity determination device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0130] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 13 As shown, the computer device includes a processor, memory, and a network interface connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores server data. The network interface communicates with external terminals via a network connection. When executed by the processor, the computer program implements a method for determining blood flow velocity.

[0131] Those skilled in the art will understand that Figure 13 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0132] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0133] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0134] In one embodiment, a computer program product or computer program is provided, the computer program product or computer program including 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 steps in the above method embodiments.

[0135] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0136] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0137] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0138] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for determining blood flow velocity, characterized in that, The method includes: Obtain the blood flow velocity calibration angle when performing ultrasound detection of blood flow velocity on the target object; Obtain the blood flow velocity detection angle when performing ultrasound detection on the target object; According to the center frequency of the emitted ultrasonic wave, the ultrasonic echo signal corresponding to the target object is demodulated to obtain the demodulated echo signal. The demodulated echo signal is calibrated based on the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain a calibrated echo signal. The blood flow velocity image of the target object is determined based on the calibration echo signal.

2. The method according to claim 1, characterized in that, The step of calibrating the demodulated echo signal based on the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain a calibrated echo signal includes: The demodulated echo signal is transformed in the signal domain to determine the frequency points of each echo signal in the frequency domain. Based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency points of each echo signal in the frequency domain are adjusted to obtain the frequency adjustment points of each echo signal. The calibrated echo signal is obtained by performing an inverse signal domain transformation on each of the frequency adjustment points of the echo signal.

3. The method according to claim 2, characterized in that, The step of performing signal domain transformation on the demodulated echo signal to determine the frequency points of each echo signal in the frequency domain includes: The demodulated echo signal is transformed in the signal domain to obtain the frequency domain of the initial modulated echo signal; Based on the blood flow velocity detection angle and the blood flow velocity calibration angle, the frequency domain of the initial modulated echo signal is extended to obtain the extended modulated echo signal frequency domain. Extract each frequency point of the echo signal frequency domain from the extended adjusted echo signal frequency domain.

4. The method according to claim 2, characterized in that, The step of adjusting the frequency points of each echo signal based on the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain the frequency adjustment points of each echo signal includes: The echo signal frequency adjustment value is determined based on the blood flow velocity detection angle and the blood flow velocity calibration angle. Using the amplitude of each echo signal frequency point as a constraint, and adjusting each echo signal frequency point according to the echo signal frequency adjustment value, the frequency adjustment points of each echo signal are obtained.

5. The method according to claim 2, characterized in that, The step of performing inverse signal domain transformation on each of the echo signal frequency adjustment points to obtain the calibration echo signal includes: Interpolation processing is performed on each of the echo signal frequency adjustment points to obtain the frequency domain of the interpolated adjusted echo signal; The interpolated echo signal is subjected to inverse signal domain transformation in the frequency domain to obtain the calibration echo signal.

6. The method according to any one of claims 1 to 5, characterized in that, Determining the blood flow velocity image of the target object based on the calibration echo signal includes: Acquire the calibration echo signal corresponding to each Doppler ultrasound channel; Beamforming is performed on each of the calibration echo signals to obtain a composite echo signal; The synthesized echo signal is processed by pulse Doppler link processing to obtain the blood flow velocity image of the target object.

7. The method according to claim 1, characterized in that, After the step of determining the blood flow velocity image of the target object based on the calibration echo signal, the method further includes: The blood flow velocity image is sampled according to a preset time interval to obtain a blood flow velocity sampling data set; The blood flow velocity sampling data set is visualized to obtain a pulsed Doppler image.

8. A blood flow velocity determining device, characterized in that, The device includes: The data acquisition module is used to acquire the blood flow velocity calibration angle when performing ultrasound detection of blood flow velocity on the target object; The data calibration module is used to acquire the blood flow velocity detection angle when performing ultrasound detection on the target object, demodulate the ultrasound echo signal corresponding to the target object according to the center frequency of the emitted ultrasound wave to obtain a demodulated echo signal, and calibrate the demodulated echo signal according to the blood flow velocity detection angle and the blood flow velocity calibration angle to obtain a calibrated echo signal. A velocity measurement module is used to determine the blood flow velocity image of the target object based on the calibration echo signal.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 7.

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