An ultrasonic pulsed Doppler blood flow measurement method and device

Abstract

The present invention discloses an ultrasonic pulsed Doppler blood flow measurement method and device. The blood flow measurement method includes: determining the physical position of a pulsed Doppler probe; based on the physical position of the current probe, determining an array formed by the arrangement of a plurality of array elements in the probe and determining the edge position of the array; based on the blood flow direction at the position to be detected, adjusting the positions of the sub-arrays for transmitting and receiving ultrasonic waves to shift towards the edge position to determine the positions of the sub-arrays; and performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the positions of the sub-arrays. By only modifying the physical positions of the array elements participating in the current electronic beam synthesis, the steering angle is automatically enlarged, and even the steering angle that may have reached the limit (plus or minus 20 degrees) configurable by the user can be further enlarged to automatically meet the measurement included angle requirements of Doppler to the greatest extent.

Description

Technical Field

[0001] The present invention relates to the technical field of Doppler measurement, and particularly relates to an ultrasonic pulsed Doppler blood flow measurement method and device. Background Art

[0002] The blood flow velocity of the human body is a very important indicator in clinical diagnosis. The pulsed Doppler technique using ultrasound can be used for measurement. However, when the ultrasonic device performs quantitative measurement of the blood flow velocity, it depends on the Doppler angle being less than 60 degrees. Otherwise, the measurement error will be too large to affect clinical judgment.

[0003] Previously, the problem could be partially solved by a physician pressing the probe on the patient's body surface and adjusting using the steering angle of the beam. With the development of computing technology, the device can automatically calculate the blood flow direction using an image algorithm, and then the device automatically adjusts the steering angle based on the calculated blood flow direction. However, both of the above methods have limitations. The former requires manual operation by a physician, which is time-consuming and will also affect the position of the probe, resulting in repetition during the operation process. The latter requires that the current vascular anatomical information can meet the requirements of the preset algorithm in the image, and the execution of the algorithm has computational requirements for software and hardware, all of which will lead to limitations in application. Moreover, if the actual blood flow direction still does not meet the requirements after applying the maximum steering angle, inaccurate results will still be obtained, and the probe position needs to be adjusted. Summary of the Invention

[0004] The present invention provides an ultrasonic pulsed Doppler blood flow measurement method and device to solve the above problems existing in the prior art.

[0005] The present invention provides an ultrasonic pulsed Doppler blood flow measurement method, which includes:

[0006] S100, determining the physical position of the pulsed Doppler probe;

[0007] S200, based on the physical position of the current probe, determining the array formed by the arrangement of several elements in the probe and determining the edge position of the array;

[0008] S300, based on the blood flow direction at the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasonic waves to shift towards the edge position and determining the position of the sub-array;

[0009] S400, performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array.

[0010] Preferably,

[0011] Preferably, the S200 includes: when the array formed by arranging a plurality of array elements is a one-dimensional array, the edge positions include a first edge position at the head of the array and a second edge position at the tail of the array;

[0012] Correspondingly, the S300 includes: a first straight line is formed by connecting the first edge position and the position to be detected; the first straight line and the blood vessel direction are set as a first acute angle, a second straight line is formed by connecting the second edge position and the position to be detected; the second straight line and the blood vessel direction are set as a second acute angle, and it is judged whether the first acute angle is smaller than the second acute angle. If so, the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift towards the first edge position of the array; if the first acute angle is greater than the second acute angle, the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift towards the second edge position of the array;

[0013] The blood vessel direction is a scalar, and the relationship between the blood vessel direction and the blood flow direction is as follows: in the case of the same blood vessel direction, the blood flow directions include: from left to right of the blood vessel, or from right to left of the blood vessel.

[0014] Preferably, the S200 includes: when the array formed by arranging a plurality of array elements is a one-dimensional array, the edge positions include a first edge position at the head of the array and a second edge position at the tail of the array;

[0015] Correspondingly, the S300 includes:

[0016] S301, based on the physical position of the current probe, adjust the sub-array to shift towards the first edge position, monitor whether the Doppler angle is less than or equal to the standard Doppler angle. If so, execute step S302; if not, execute step S303;

[0017] S302, adjust the sub-array for transmitting and receiving ultrasonic waves to shift towards the first edge position of the array, and determine the first edge position as the position of the sub-array;

[0018] S303, adjust the sub-array for transmitting and receiving ultrasonic waves to shift towards the second edge position of the array, and determine the second edge position as the position of the sub-array.

[0019] Preferably, the S200 includes: when the array formed by arranging a plurality of array elements is a two-dimensional array, the edge positions include a plurality of edge positions;

[0020] Correspondingly, the S300 includes: each edge position and the position to be detected are respectively connected to form a plurality of straight lines, each straight line forms an acute angle with the blood vessel direction, judge the position of the array element corresponding to the straight line with the smallest acute angle, and set the edge position corresponding to the array element as the position of the sub-array.

[0021] Preferably, the S300 further includes:

[0022] S304, determine that the number of consecutive sub-arrays for transmitting and receiving ultrasonic waves in the probe is the selected number;

[0023] S305, taking the outermost array element among the edge positions of the array as a reference, continuously select inward the same number of array elements as the selected number as the sub-arrays for transmitting and receiving ultrasonic waves, and determine the positions of the sub-arrays.

[0024] Preferably, before the S100, it includes:

[0025] S500, start the ultrasonic pulsed Doppler measurement mode;

[0026] S600, determine whether the offset strategy condition is satisfied. If it is satisfied, execute step S100. If it is not satisfied, execute step S700;

[0027] S700, perform ultrasonic pulsed Doppler blood flow quantitative measurement using the current configuration parameters of the ultrasonic pulsed Doppler.

[0028] Preferably, the S300 further includes:

[0029] S306, when the position of the sub-array shifts towards the edge position, multiple offset positions are formed. According to the multiple offset positions, the positions of the sub-array include multiple;

[0030] S307, the positions of the multiple sub-arrays are provided for the user to select through an interaction device, and ultrasonic pulsed Doppler blood flow quantitative measurement is performed based on the position of the sub-array selected by the user and the current configuration parameters of the ultrasonic pulsed Doppler.

[0031] Preferably, the S400 includes:

[0032] S401, based on the pulsed Doppler spectrum received by the sub-array, input fixed-length data to the pulsed Doppler spectrum using a spectrum analysis algorithm. Each time, multiply the fixed-length data by a Hamming window and use FFT processing to obtain the power spectrum of the Doppler data;

[0033] S402, when the first spectrum analysis algorithm processing is completed, move the input Doppler data backward by the data of the step length, take the fixed-length Doppler data for the next spectrum analysis algorithm processing, and continuously loop this operation on the continuously sampled Doppler data to obtain the power spectrum varying with time. The step length is determined by the current scanning speed;

[0034] S403, after the spectrum analysis algorithm processes the current Doppler data, the power spectrum of this data will be obtained. The power spectrum corresponds to a spectral line in the dynamic power spectrum diagram. Map the amplitude of the spectral line to the index table of the gray value, and perform encoding display according to the color indicated by the index table of the gray value. The larger the amplitude, the larger the gray value, indicating a high power at this frequency;

[0035] S404. After processing the current data, transfer to process the next set of data. Once a continuous power spectrum is obtained, a dynamic power spectrum diagram of the Doppler signal can be plotted.

[0036] S405. Perform noise reduction processing on the dynamic power spectrum diagram. The dynamically power spectrum diagram after noise reduction processing is used as the basis for ultrasonic pulsed Doppler blood flow quantification.

[0037] Preferably, the noise reduction processing of the dynamic power spectrum diagram in S405 includes:

[0038] S4051. Extract all the characteristic components of the signal in the dynamic power spectrum diagram.

[0039] S4052. Analyze the correlation relationship between two characteristic components; the correlation between different characteristic components is represented by the inner product.

[0040] S4053. If the main characteristic component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining characteristic components and the main characteristic component. If the correlation is greater than a certain set correlation threshold, then determine that this characteristic component belongs to the clutter characteristic space and remove the high characteristic component from the signal.

[0041] S4054. Form a set of clutter characteristic spaces according to the steps of S4053, and reconstruct the filtered signal based on the set of clutter characteristic spaces.

[0042] The present invention also provides an ultrasonic pulsed Doppler blood flow measurement device, which includes: an ultrasonic pulsed Doppler probe, an interaction device, and a measurement control module;

[0043] The measurement control module is respectively connected to the ultrasonic pulsed Doppler probe and the interaction device;

[0044] The ultrasonic pulsed Doppler probe includes a plurality of array - arranged elements, and controls a continuous plurality of elements to transmit and receive ultrasonic waves through the measurement control module to form a sub - array;

[0045] The interaction device is used for control operation interaction between the user and the measurement control module;

[0046] After starting the ultrasonic pulsed Doppler blood flow measurement device, the interaction device displays whether the offset strategy condition is met. If the offset strategy condition is met, after the ultrasonic pulsed Doppler probe determines the physical position, based on the physical position of the current probe, the edge position of the array is determined, and based on the blood flow direction of the position to be detected, the positions of the sub-arrays for transmitting and receiving ultrasonic waves are adjusted to offset towards the edge position, the positions of the sub-arrays are determined, and options for the positions of the sub-arrays are provided to the user. After the user selects the position of the corresponding sub-array through the interaction device, ultrasonic pulsed Doppler blood flow quantitative measurement is performed based on the position of the sub-array; if the offset strategy condition is not met, ultrasonic pulsed Doppler blood flow quantitative measurement is performed using the current configuration parameters of the ultrasonic pulsed Doppler.

[0047] Compared with the prior art, the present invention has the following advantages:

[0048] The present invention provides an ultrasonic pulsed Doppler blood flow measurement method and device. The blood flow measurement method includes: determining the physical position of the pulsed Doppler probe; based on the physical position of the current probe, determining an array formed by the arrangement of a plurality of array elements in the probe, and determining the edge position of the array; based on the blood flow direction of the position to be detected, adjusting the positions of the sub-arrays for transmitting and receiving ultrasonic waves to offset towards the edge position, and determining the positions of the sub-arrays; performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the positions of the sub-arrays. By only modifying the physical positions of the array elements participating in the current electronic beam synthesis, the steering angle is automatically enlarged, and even the steering angle that may have reached the user-configurable limit (plus or minus 20 degrees) can be further enlarged to automatically meet the measurement angle requirement of Doppler to the greatest extent.

[0049] Other features and advantages of the present invention will be described in the following specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures specifically pointed out in the written specification, claims, and drawings.

[0050] The technical solutions of the present invention will be further described in detail below through the drawings and embodiments. Description of the Drawings

[0051] The drawings are used to provide a further understanding of the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation to the present invention. In the drawings:

[0052] Figure 1 is a flowchart of an ultrasonic pulsed Doppler blood flow measurement method in an embodiment of the present invention;

[0053] Figure 2 is a schematic structural diagram of a linear array in a probe in an embodiment of the present invention;

[0054] Figure 3 Schematic diagram of the principle of increasing the steering angle due to the position offset of sub-arrays in the embodiments of the present invention;

[0055] Figure 4 Schematic diagram of the structure of an ultrasonic pulsed Doppler blood flow measurement device in the embodiments of the present invention. Specific embodiments

[0056] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not intended to limit the present invention.

[0057] The embodiments of the present invention provide an ultrasonic pulsed Doppler blood flow measurement method. Please refer to Figure 1 , and the method includes:

[0058] S100, determining the physical position of the pulsed Doppler probe;

[0059] S200, based on the physical position of the current probe, determining the array formed by the arrangement of a plurality of array elements in the probe, and determining the edge position of the array;

[0060] S300, based on the blood flow direction at the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasonic waves to offset towards the edge position, and determining the position of the sub-array;

[0061] S400, performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array.

[0062] The working principle of the above technical solution is as follows: The solution adopted in this embodiment is to determine the physical position of the pulsed Doppler probe; based on the physical position of the current probe, determine the array formed by the arrangement of a plurality of array elements in the probe, and determine the edge position of the array; based on the blood flow direction at the position to be detected, adjust the position of the sub-array for transmitting and receiving ultrasonic waves to offset towards the edge position, and determine the position of the sub-array; perform ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array.

[0063] It should be noted that the traditional operation method A: After the operator finds the blood vessel, activates the roi display, moves the roi to the center of the blood vessel, and then adjusts the steering angle of the beam and the position of the probe respectively. After the operator determines that the Doppler angle reaches the standard range, starts the pulsed Doppler quantitative detection.

[0064] In addition, the method B based on image blood vessel recognition: After the operator finds the blood vessel, activates the roi display, and then an algorithm capable of analyzing based on the image content will execute. The operation subject changes from a person to a program. Similarly, the roi is moved to the center of the blood vessel, and then the steering angle of the beam is adjusted. After determining that the Doppler angle reaches the standard range, starts the pulsed Doppler quantitative detection.

[0065] However, the above two existing methods have the following disadvantages:

[0066] Method A: It has high requirements for the operator's skills and consumes a long time; if the operator fails to understand the Doppler angle limit, it will lead to incorrect actual measurement results and affect clinical diagnosis.

[0067] Method B: It has high requirements for the image recognition algorithm and is prone to malfunction due to the complexity of ultrasonic images, with insufficient stability; the computing power for image recognition requires the hardware to be satisfied, otherwise the function cannot be used due to too long computing time; if the obtained ultrasonic image cannot be effectively recognized by the algorithm, it will lead to more serious time consumption and even incorrect measurement results.

[0068] In the present invention, by using the physical position offset of the array elements of the currently activated ultrasonic probe at the timing of starting pulsed Doppler measurement for quantitative detection, while keeping the physical position of the probe unchanged, the array elements participating in transmission are moved to the positions at the outermost edges of the probe to minimize the angle (Doppler angle) between the ultrasonic pulse and the blood flow direction, thereby minimizing the error of the Doppler measurement result and providing accurate measurement results for clinical diagnosis.

[0069] The beneficial effects of the above technical solution are: By adopting the solution provided in this embodiment, the steering angle is automatically enlarged by only modifying the physical positions of the array elements participating in the current electronic beam synthesis, and even the steering angle that may have reached the user-configurable limit (plus or minus 20 degrees) can be further enlarged to automatically meet the measurement angle requirements of Doppler to the greatest extent.

[0070] In another embodiment, the S200 includes: when the array formed by arranging several array elements is a one-dimensional array, the edge positions include a first edge position at the head of the array and a second edge position at the tail of the array;

[0071] Correspondingly, the S300 includes:

[0072] The first edge position is connected to the position to be detected to form a first straight line; the first straight line is set to a first acute angle with the blood vessel direction, the second edge position is connected to the position to be detected to form a second straight line; the second straight line is set to a second acute angle with the blood vessel direction, determine whether the first acute angle is less than the second acute angle, if so, adjust the sub-array for transmitting and receiving ultrasonic waves to offset towards the first edge position of the array; if the first acute angle is greater than the second acute angle, adjust the sub-array for transmitting and receiving ultrasonic waves to offset towards the second edge position of the array;

[0073] The blood vessel orientation is a scalar, and the relationship between the blood vessel orientation and the blood flow direction is as follows: When the blood vessel orientations are the same, the blood flow directions include: from left to right of the blood vessel, or from right to left of the blood vessel.

[0074] In a two-dimensional plane, if the blood vessel is in a horizontal line position, then the blood flow can be from left to right or from right to left. The blood flow direction can be directional. In this embodiment, the direction of the blood vessel orientation is not specified. Therefore, the blood vessel orientation and the first straight line or the second straight line will definitely present an acute angle and an obtuse angle (the case where the two are at a 90° right angle is not considered here).

[0075] The working principle of the above technical solution is as follows: The solution adopted in this embodiment is that S200 includes: When the array formed by arranging several elements is a one-dimensional array, the edge positions include a first edge position at the head of the array and a second edge position at the tail of the array; Correspondingly, S300 includes: The first edge position is connected to the position to be detected to form a first straight line; The first straight line and the blood vessel orientation are set as a first acute angle, the second edge position is connected to the position to be detected to form a second straight line; The second straight line and the blood vessel orientation are set as a second acute angle, and it is judged whether the first acute angle is less than the second acute angle. If so, the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift towards the first edge position of the array; If the first acute angle is greater than the second acute angle, the sub-array for transmitting and receiving ultrasonic waves is adjusted to shift towards the second edge position of the array; The blood vessel orientation is a scalar, and the relationship between the blood vessel orientation and the blood flow direction is as follows: When the blood vessel orientations are the same, the blood flow directions include: from left to right of the blood vessel, or from right to left of the blood vessel.

[0076] The solution provided in this embodiment is to find out how to find the sub-array position that meets the Doppler angle by adjusting the position of the sub-array for transmitting ultrasonic waves, without the need to perform blood flow measurement by means of multiple trial adjustments of directions, etc.

[0077] In another embodiment, S200 includes: When the array formed by arranging several elements is a one-dimensional array, the edge positions include a first edge position at the head of the array and a second edge position at the tail of the array;

[0078] Correspondingly, S300 includes:

[0079] S301, based on the physical position of the current probe, adjust the sub-array to shift towards the first edge position, and monitor whether the Doppler angle is less than or equal to the standard Doppler angle. If so, execute step S302; If not, execute step S303;

[0080] S302, adjust the sub-array for transmitting and receiving ultrasonic waves to shift towards the first edge position of the array, and determine the first edge position as the position of the sub-array;

[0081] In S303, shift the sub-array that emits and receives ultrasonic waves towards the second edge position of the array, and determine the second edge position as the position of the sub-array.

[0082] The technical principle of the above technical solution is as follows: Based on the physical position of the current probe, shift the sub-array towards the first edge position, and monitor whether the Doppler angle is less than or equal to the standard Doppler angle. If so, shift the sub-array that emits and receives ultrasonic waves towards the first edge position of the array, and determine the first edge position as the position of the sub-array; if not, shift the sub-array that emits and receives ultrasonic waves towards the second edge position of the array, and determine the second edge position as the position of the sub-array.

[0083] This embodiment can accurately obtain the Doppler blood flow measurement result with a maximum of two adjustments of the sub-array position. If the first edge position meets the measurement requirements, the measurement can be directly performed. If not, it is directly adjusted to the second edge position offset, and the measurement can be directly performed without multiple measurements.

[0084] Specifically, the following is an introduction to the Doppler blood flow measurement instrument: The probe is composed of multiple physical array elements, generally arranged in a one-dimensional manner in a straight line / curve (there are also two-dimensional arranged entities).

[0085] The sub-array is composed of a part of continuous array elements in the probe, participates in one actual ultrasonic wave emission and reception, and can perform beam synthesis by controlling the actual emission time of each array element, including the adjustment of the steering angle.

[0086] The synthesized beam can be formed by determining the focal position and the participating sub-array.

[0087] When detecting the blood flow of surface blood vessels by pulsed Doppler, the array element position offset is used to increase the steering angle to minimize the Doppler angle.

[0088] For example, Figure 2 is a schematic structural diagram of the linear array in the probe. As Figure 2 shown, 1-14 are array elements, arranged in an array, and the overall linear array combination is the probe. Among them, the sub-array is composed of 1-4, and the synthesized beam focus is point P.

[0089] Another example, Figure 3 is a schematic diagram of the principle of increasing the steering angle by the sub-array position offset. When using the 5-9 array elements as the sub-array to emit ultrasonic waves, the synthesized beam direction is ·0, L represents the blood flow direction, and the angle between the synthesized beam direction B0 and the blood flow direction is α. Through the offset of the sub-array position in this embodiment, the synthesized beam direction is transferred from B0 to B1, and the angle between B1 and the blood flow direction L is β, and β is smaller than α. In the Doppler effect, the smaller the angle, the more accurate the detection result.

[0090] Combined with this embodiment, when 5 - 9 array elements are used as a sub - array to emit ultrasonic waves, it may not meet the Doppler angle. Set the positions corresponding to 1 - 4 array elements as the first edge positions, and the positions corresponding to 10 - 14 array elements as the second edge positions. It can be illustrated by this example that the angle formed by the second straight line formed by the connection line between the second edge position and the position to be detected and the blood flow direction is smaller. Therefore, the sub - array for emitting and receiving ultrasonic waves can be adjusted to shift towards the second edge position of the array, and the second edge position is determined as the position of the sub - array.

[0091] By adjusting the offset direction of the sub - array for emitting and receiving ultrasonic waves at most twice, accurate Doppler blood flow measurement can be carried out. There is no need to conduct multiple experimental adjustments to find the position that meets the Doppler angle, which improves the accuracy of Doppler blood flow measurement and the measurement efficiency.

[0092] It should be noted that the steering angle in ultrasound refers to the angle between the direction of the beam and the axial direction of the probe. In normal situations such as Figure 2 the B0 direction in, at this time the steering angle is 0. If the actual beam direction changes from ·0 to B1, then the steering angle increases, from 0 to non - zero, and at this time the steering angle is equal to the angle between B0 and B1.

[0093] In another embodiment,

[0094] The S200 includes: when the array formed by arranging several array elements is a two - dimensional array, the edge positions include several edge positions;

[0095] Correspondingly, the S300 includes: each edge position is respectively connected to the position to be detected to form several straight lines, each straight line forms an acute angle with the blood vessel direction, determine the position of the array element corresponding to the straight line with the smallest acute angle, and set the edge position corresponding to this array element as the position of the sub - array.

[0096] The working principle of the above - mentioned technical solution is: The solution adopted in this embodiment is that the S200 includes: when the array formed by arranging several array elements is a two - dimensional array, the edge positions include several edge positions; Correspondingly, the S300 includes: each edge position is respectively connected to the position to be detected to form several straight lines, each straight line forms an acute angle with the blood vessel direction, determine the position of the array element corresponding to the straight line with the smallest acute angle, and set the edge position corresponding to this array element as the position of the sub - array.

[0097] When the array is a two-dimensional array, based on the same principle, the acute angle between the straight line and the blood vessel direction is determined, and the smallest acute angle is determined from the formed acute angles. This acute angle is formed by a certain straight line and the blood vessel direction. Therefore, this straight line can be determined. After determining the straight line, it can be determined which edge position forms the straight line with the position to be detected. Therefore, the corresponding edge position can be found, and by adjusting the sub-arrays for transmitting and receiving ultrasonic waves to offset towards the found edge position of the array, the Doppler blood flow measurement scheme can be accurately implemented.

[0098] In another embodiment, the S300 further includes:

[0099] S304, determining that the number of consecutive sub-arrays for transmitting and receiving ultrasonic waves in the probe is the selected number;

[0100] S305, taking the outermost array element among the edge positions of the array as a reference, and continuously selecting inward the same number of array elements as the selected number as the sub-arrays for transmitting and receiving ultrasonic waves to determine the positions of the sub-arrays.

[0101] The working principle of the above technical solution is: The solution adopted in this embodiment is to determine that the number of consecutive sub-arrays for transmitting and receiving ultrasonic waves in the probe is the selected number; taking the outermost array element among the edge positions of the array as a reference, and continuously selecting inward the same number of array elements as the selected number as the sub-arrays for transmitting and receiving ultrasonic waves to determine the positions of the sub-arrays.

[0102] Transferring the sub-arrays to other positions of the probe can reduce the Doppler angle, thereby increasing the measurement accuracy.

[0103] In another embodiment, before the S100, it includes:

[0104] S500, starting the ultrasonic pulsed Doppler measurement mode;

[0105] S600, determining whether the offset strategy condition is satisfied. If it is satisfied, execute step S100. If it is not satisfied, execute step S700;

[0106] S700, performing ultrasonic pulsed Doppler blood flow quantitative measurement using the current configuration parameters of ultrasonic pulsed Doppler.

[0107] The working principle of the above technical solution is: The solution adopted in this embodiment is to start the ultrasonic pulsed Doppler measurement mode; determine whether the offset strategy condition is satisfied. If it is satisfied, execute step S100. If it is not satisfied, execute step of performing ultrasonic pulsed Doppler blood flow quantitative measurement using the current configuration parameters of ultrasonic pulsed Doppler.

[0108] Determine whether the offset strategy is applicable. If it is applicable, perform the offset to the edge of the sound head (the actual implementation can independently set the offset to the proximal end / distal end). If it is not applicable, directly use the default parameters. If an offset operation occurs, then mark the original user ROI position in the UI and the ROI position after applying the strategy; activate the strategy selection button. The user determines whether they are satisfied with the current strategy. If satisfied, perform the operation according to the original strategy. If not satisfied, they can use the activated button to adjust the strategy, and this step is supported to be looped. After the pulsed Doppler completes multiple measurement cycles for the patient's vascular blood flow velocity, the user can adopt the freeze strategy and then measure the actual blood flow velocity. Applying subarray offset will reduce the Doppler angle, reduce measurement errors, and improve accuracy.

[0109] In another embodiment, the S300 further includes:

[0110] S306, when the position of the subarray offsets towards the edge position, multiple offset positions are formed. According to the multiple offset positions, the position of the subarray includes multiple ones;

[0111] S307, the positions of multiple subarrays are provided for the user to select through an interaction device, and based on the position of the subarray selected by the user and the current configuration parameters of the ultrasonic pulsed Doppler, ultrasonic pulsed Doppler blood flow quantitative measurement is performed.

[0112] For example, on the image of the intensive care device UI, the actual position of the PW sampling line after applying this strategy and the old position before application will be displayed. The control panel of the UI will display option buttons [Edge 1 / Edge 2 / Center / Original Position] that support adjustment; the user can use this button to quickly apply a new strategy for situations they are not satisfied with.

[0113] In another embodiment, the S400 includes:

[0114] S401, based on the pulsed Doppler spectrum received by the subarray, input data of a fixed length to the pulsed Doppler spectrum using a spectrum analysis algorithm. Each time, multiply the data of the fixed length by a Hamming window and use FFT processing to obtain the power spectrum of the Doppler data;

[0115] S402, when the first spectrum analysis algorithm processing is completed, move the input Doppler data backward by the data of the step length, take the Doppler data of the fixed length for the next spectrum analysis algorithm processing, and continuously loop this operation for the continuously sampled Doppler data to obtain the power spectrum that changes with time. The step length is determined by the current scanning speed;

[0116] S403. After the spectral analysis algorithm processes the current Doppler data, the power spectrum of the data is obtained. The power spectrum corresponds to a spectral line in the dynamic power spectrum diagram. The amplitude of the spectral line is mapped to the index table of grayscale values, and encoding display is performed according to the colors indicated by the index table of grayscale values. The larger the amplitude, the larger the grayscale value, indicating high power at this frequency;

[0117] S404. After processing the current data, transfer to process the next set of data. By obtaining continuous power spectra, the dynamic power spectrum diagram of the Doppler signal can be drawn;

[0118] S405. Perform noise reduction processing on the dynamic power spectrum diagram. The dynamically processed power spectrum diagram after noise reduction is used as the basis for ultrasonic pulsed Doppler blood flow quantification.

[0119] The working principle of the above technical solution is as follows: The solution adopted in this embodiment is in the spectral analysis algorithm. Since the Doppler echo signal is a non-stationary signal, the short-time Fourier transform is used to analyze the signal in the frequency domain. The selection of the window function affects the processing effect, and the Hamming window is selected as the window function in this article. Due to the existence of tissue clutter that will submerge the blood flow signal, a filter is used as the filter for the pulsed Doppler algorithm processing. The actual signal is successfully processed by the filter to extract the blood flow signal with low energy and high frequency. The pulsed Doppler algorithm is used to process the data, optimizing the dynamic power spectrum diagram of the ultrasonic pulsed Doppler.

[0120] In another embodiment, the noise reduction processing of the dynamic power spectrum diagram in S405 includes:

[0121] S4051. Extract all the characteristic components of the signal in the dynamic power spectrum diagram;

[0122] S4052. Analyze the correlation relationship between two characteristic components; the correlation between different characteristic components is represented by the inner product;

[0123] The calculation formula for the correlation is as follows:

[0124]

[0125] where, e k represents the characteristic component of the slow echo signal, e l represents the characteristic component for which the correlation is to be calculated, u k represents the k-th column of matrix U, and matrix U is the left singular matrix, v k represents the k-th column of matrix V, and matrix V is the right singular matrix; K represents the smallest integer greater than or equal to N / 2, and N represents the number of samples in the slow time set; Z l represents the l-th column of matrix Z. * represents the orthogonal relationship between e k and e l .

[0126] Therefore, the inner product between two feature components in the correlation relationship can be conveniently determined by the element in the lower left corner of the matrix.

[0127] S4053: If the main feature component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining feature components and the main feature component. If the correlation is greater than a set correlation threshold, determine that the feature component belongs to the clutter feature space and remove the high feature component from the signal.

[0128] S4054: Form a set of clutter feature spaces according to the steps of S4053, and reconstruct the filtered signal based on the set of clutter feature spaces.

[0129] Traditional filtering algorithms include IIR filters with projection initialization and polynomial regression filters. After the filter design is completed, its cut-off frequency is fixed. When there is fast movement in the tissue, clutter with a large frequency shift will appear. In order to suppress the clutter signal of fast movement, traditional filtering algorithms will set a large cut-off frequency. At this time, it is inevitable that some blood flow signals will be wrongly filtered while filtering the clutter. It is precisely because the cut-off frequency of traditional filtering algorithms cannot automatically adapt to the movement of the tissue that the detection accuracy of blood flow signals is ultimately reduced.

[0130] In order to suppress the clutter components in slow-time signals, it is necessary to determine whether each feature component belongs to the clutter feature space. By analyzing the feature components, it can be determined whether they belong to the clutter feature space, and then filtering processing can be carried out. In terms of determining the dimension of the clutter feature space, after the signal reconstruction method is changed, the correlation between feature components can be conveniently obtained. The filtering algorithm of this embodiment adds a method for determining the correlation of feature components, so as to more effectively filter out clutter components and improve the estimation accuracy of blood flow velocity.

[0131] In another embodiment, this embodiment provides an ultrasonic pulsed Doppler blood flow measurement device. Please refer to Figure 4 , this device includes: an ultrasonic pulsed Doppler probe, an interaction device, and a measurement control module;

[0132] The measurement control module is respectively connected to the ultrasonic pulsed Doppler probe and the interaction device;

[0133] The ultrasonic pulsed Doppler probe includes a plurality of arrayed elements, and a plurality of consecutive elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form a sub-array;

[0134] The interaction device is used for the control operation interaction between the user and the measurement control module;

[0135] After starting the ultrasonic pulsed Doppler blood flow measurement device, the interaction device displays whether the offset strategy condition is satisfied. If the offset strategy condition is satisfied, after the ultrasonic pulsed Doppler probe determines the physical position, based on the physical position of the current probe, the edge position of the array is determined, and based on the blood flow direction of the position to be detected, the positions of the sub-arrays for transmitting and receiving ultrasonic waves are adjusted to offset towards the edge position, the positions of the sub-arrays are determined, and options for the positions of the sub-arrays are provided to the user. After the user selects the position of the corresponding sub-array through the interaction device, ultrasonic pulsed Doppler blood flow quantitative measurement is performed based on the position of the sub-array; if the offset strategy condition is not satisfied, ultrasonic pulsed Doppler blood flow quantitative measurement is performed using the current configuration parameters of the ultrasonic pulsed Doppler.

[0136] The working principle of the above technical solution is: The solution adopted in this embodiment is that the device includes: an ultrasonic pulsed Doppler probe, an interaction device, and a measurement control module;

[0137] The measurement control module is respectively connected to the ultrasonic pulsed Doppler probe and the interaction device;

[0138] The ultrasonic pulsed Doppler probe includes a number of arrayed elements, and a number of consecutive elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form a sub-array; the interaction device is used for the control operation interaction between the user and the measurement control module; after starting the ultrasonic pulsed Doppler blood flow measurement device, the interaction device displays whether the offset strategy condition is satisfied. If the offset strategy condition is satisfied, after the ultrasonic pulsed Doppler probe determines the physical position, based on the physical position of the current probe, the edge position of the array is determined, and based on the blood flow direction of the position to be detected, the positions of the sub-arrays for transmitting and receiving ultrasonic waves are adjusted to offset towards the edge position, the positions of the sub-arrays are determined, and options for the positions of the sub-arrays are provided to the user. After the user selects the position of the corresponding sub-array through the interaction device, ultrasonic pulsed Doppler blood flow quantitative measurement is performed based on the position of the sub-array; if the offset strategy condition is not satisfied, ultrasonic pulsed Doppler blood flow quantitative measurement is performed using the current configuration parameters of the ultrasonic pulsed Doppler.

[0139] The beneficial effect of the above technical solution is: By adopting the solution provided in this embodiment, the steering angle is automatically enlarged by only modifying the physical positions of the elements participating in the current electronic beam synthesis, and even the steering angle that may have reached the user-configurable limit (plus or minus 20 degrees) can be further enlarged to automatically meet the measurement included angle requirements of Doppler to the greatest extent.

[0140] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. An ultrasonic pulsed Doppler blood flow measurement method, characterized in that, Including: S100, determining the physical position of the pulsed Doppler probe; S200, based on the physical position of the current probe, determining the array formed by the arrangement of several array elements in the probe, and determining the edge position of the array; S300, based on the blood flow direction of the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasonic waves to shift towards the edge position, and determining the position of the sub-array; S400, performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array; S200 includes: when the array formed by the arrangement of several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array; Correspondingly, S300 includes: connecting the first edge position and the position to be detected to form a first straight line; setting the first straight line and the blood vessel direction to a first acute angle, connecting the second edge position and the position to be detected to form a second straight line; setting the second straight line and the blood vessel direction to a second acute angle, and determining whether the first acute angle is less than the second acute angle. If so, adjusting the sub-array for transmitting and receiving ultrasonic waves to shift towards the first edge position of the array; if the first acute angle is greater than the second acute angle, adjusting the sub-array for transmitting and receiving ultrasonic waves to shift towards the second edge position of the array; The blood vessel direction is a scalar, and the relationship between the blood vessel direction and the blood flow direction is as follows: in the case of the same blood vessel direction, the blood flow direction includes: from left to right in the blood vessel, or from right to left in the blood vessel.

2. An ultrasonic pulsed Doppler blood flow measurement method, characterized in that, Including: S100, determining the physical position of the pulsed Doppler probe; S200, based on the physical position of the current probe, determining the array formed by the arrangement of several array elements in the probe, and determining the edge position of the array; S300, based on the blood flow direction of the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasonic waves to shift towards the edge position, and determining the position of the sub-array; S400, performing ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array; S200 includes: when the array formed by the arrangement of several array elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array; Correspondingly, S300 includes: S301, based on the physical position of the current probe, adjusting the sub-array to shift towards the first edge position, monitoring whether the Doppler angle is less than or equal to the standard Doppler angle. If so, performing step S302; if not, performing step S303; S302, adjusting the sub-array for transmitting and receiving ultrasonic waves to shift towards the first edge position of the array, and determining the first edge position as the position of the sub-array; S303, adjusting the sub-array for transmitting and receiving ultrasonic waves to shift towards the second edge position of the array, and determining the second edge position as the position of the sub-array.

3. An ultrasonic pulsed Doppler blood flow measurement method, characterized in that, Including: S100, determining the physical position of the pulsed Doppler probe; S200, based on the physical position of the current probe, determining the array formed by the arrangement of several array elements in the probe, and determining the edge position of the array; S300, based on the blood flow direction of the position to be detected, adjusting the position of the sub-array for transmitting and receiving ultrasonic waves to shift towards the edge position, and determining the position of the sub-array; S400 performs ultrasonic pulsed Doppler blood flow quantitative measurement based on the positions of sub-arrays; The S200 includes: when the array formed by arranging a plurality of array elements is a two-dimensional array, the edge positions include a plurality of edge positions; Correspondingly, the S300 includes: each edge position and the position to be detected are respectively connected to form a plurality of straight lines, each straight line forms an acute angle with the blood vessel direction, determine the position of the array element corresponding to the straight line with the smallest acute angle, and set the edge position corresponding to the array element as the position of the sub-array.

4. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 1, characterized in that, The S300 further includes: S304, determining that the number of consecutive sub-arrays for transmitting and receiving ultrasonic waves in the probe is the selected number; S305, taking the outermost array element among the edge positions of the array as a reference, continuously selecting inward the same number of array elements as the selected number as the sub-arrays for transmitting and receiving ultrasonic waves, and determining the positions of the sub-arrays.

5. A method for ultrasonic pulsed Doppler blood flow measurement according to claim 1, characterized in that, Before the S100 includes: S500, starting the ultrasonic pulsed Doppler measurement mode; S600, determining whether the offset strategy condition is met. If it is met, execute step S100. If it is not met, execute step S700; S700, performing ultrasonic pulsed Doppler blood flow quantitative measurement using the current configuration parameters of ultrasonic pulsed Doppler.

6. The ultrasonic pulsed Doppler blood flow measurement method according to claim 1, characterized in that, The S300 further includes: S306, when the position of the sub-array shifts towards the edge position, a plurality of offset positions are formed. According to the plurality of offset positions, the positions of the sub-array include a plurality; S307, the positions of the plurality of sub-arrays are provided for the user to select through an interaction device, and ultrasonic pulsed Doppler blood flow quantitative measurement is performed based on the positions of the sub-arrays selected by the user using the current configuration parameters of ultrasonic pulsed Doppler.

7. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 1, characterized in that, The S400 includes: S401, based on the pulsed Doppler spectrum received by the sub-array, inputting data of a fixed length to the pulsed Doppler spectrum using a spectrum analysis algorithm, multiplying the data of the fixed length by a Hamming window each time, and using FFT processing to obtain the power spectrum of the Doppler data; S402, after the first spectrum analysis algorithm processing is completed, shift the input Doppler data backward by the data of the step length, take the Doppler data of the fixed length for the next spectrum analysis algorithm processing, and continuously loop this operation on the continuously sampled Doppler data to obtain the power spectrum varying with time; wherein the step length is determined by the current scanning speed; S403, after the spectrum analysis algorithm processes the current Doppler data, the power spectrum of the data will be obtained. The power spectrum corresponds to a spectral line in the dynamic power spectrum diagram. Map the amplitude of the spectral line to the index table of gray values, and perform color coding display according to the color indicated by the index table of gray values; the larger the amplitude, the larger the gray value, indicating high power at this frequency; S404, after processing the current data, transfer to process the next set of data, and the continuous power spectrum can be used to draw the dynamic power spectrum diagram of the Doppler signal; S405, perform noise reduction processing on the dynamic power spectrum diagram, and use the dynamically power spectrum diagram after noise reduction processing as the basis for ultrasonic pulsed Doppler blood flow quantitative measurement.

8. A method for measuring ultrasonic pulsed Doppler blood flow according to claim 7, characterized in that, In the S405, the noise reduction processing of the dynamic power spectrum diagram includes: S4051, extracting all the characteristic components of the signal in the dynamic power spectrum diagram; S4052. Analyze the correlation relationship between two characteristic components; the correlation between different characteristic components is represented by the inner product. S4053. If the main characteristic component is determined to be a clutter component according to the frequency threshold, calculate the correlation between the remaining characteristic components and the main characteristic component. If the correlation is greater than a set correlation threshold, determine that this characteristic component belongs to the clutter feature space and remove the high characteristic component from the signal. S4054. Form a set of clutter feature spaces according to the steps of S4053, and reconstruct the filtered signal based on the set of clutter feature spaces.

9. An ultrasonic pulsed Doppler blood flow measuring device, characterized in that, Including: An ultrasonic pulsed Doppler probe, an interaction device, and a measurement control module. The measurement control module is respectively connected to the ultrasonic pulsed Doppler probe and the interaction device. The ultrasonic pulsed Doppler probe includes a plurality of arrayed elements, and a plurality of consecutive elements are controlled by the measurement control module to transmit and receive ultrasonic waves to form a sub-array. The interaction device is used for the control operation interaction between the user and the measurement control module. After starting the ultrasonic pulsed Doppler blood flow measurement device, the interaction device displays whether the offset strategy condition is satisfied. If the offset strategy condition is satisfied, after the ultrasonic pulsed Doppler probe determines the physical position, based on the physical position of the current probe, determine the edge position of the array, and based on the blood flow direction of the position to be detected, adjust the position of the sub-array that emits and receives ultrasonic waves to offset towards the edge position, determine the position of the sub-array, and provide the sub-array position options to the user. After the user selects the position of the corresponding sub-array through the interaction device, perform ultrasonic pulsed Doppler blood flow quantitative measurement based on the position of the sub-array; if the offset strategy condition is not satisfied, perform ultrasonic pulsed Doppler blood flow quantitative measurement using the current configuration parameters of the ultrasonic pulsed Doppler. When the array formed by arranging a plurality of elements is a one-dimensional array, the edge position includes a first edge position at the head of the array and a second edge position at the tail of the array. The first edge position is connected to the position to be detected to form a first straight line; the first straight line and the blood vessel direction are set as a first acute angle, the second edge position is connected to the position to be detected to form a second straight line; the second straight line and the blood vessel direction are set as a second acute angle. Judge whether the first acute angle is less than the second acute angle. If so, adjust the sub-array that emits and receives ultrasonic waves to offset towards the first edge position of the array; if the first acute angle is greater than the second acute angle, adjust the sub-array that emits and receives ultrasonic waves to offset towards the second edge position of the array. The blood vessel direction is a scalar, and the relationship between the blood vessel direction and the blood flow direction is as follows: in the case of the same blood vessel direction, the blood flow direction includes: from left to right of the blood vessel, or from right to left of the blood vessel.

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