Blood vessel strain measurement method, ultrasonic imaging equipment and medium

Abstract

The blood vessel strain measurement method comprises the following steps: obtaining an ultrasonic image set of a target blood vessel in a period of time, and obtaining a blood flow velocity of the target blood vessel in a period of time; determining a first blood flow velocity and a second blood flow velocity from the blood flow velocities of the target blood vessel within a period of time based on a preset rule, and acquiring a first time point corresponding to the first blood flow velocity and a second time point corresponding to the second blood flow velocity; and acquiring a target ultrasonic image set between the first time point and the second time point from the ultrasonic image sets, and measuring a strain value of the target blood vessel based on the target ultrasonic image set. A relatively fixed frame of ultrasonic image can be selected each time and can be used as an initial frame for calculating the strain value, so that the calculated strain value is relatively stable, and the repeatability is relatively good. The invention further provides ultrasonic imaging equipment and a medium.

Description

Technical Field

[0001] This application relates to the field of ultrasonic imaging technology, and particularly to a method for measuring vascular strain, an ultrasonic imaging device, and a medium. Background Art

[0002] The common carotid artery is an important part connecting the heart and the blood vessels of the brain. Abnormalities in the structure and function of the common carotid artery may lead to cardiovascular and cerebrovascular diseases such as atherosclerosis and stroke. Therefore, it is an important detection window for the prevention, early diagnosis, clinical treatment, and rehabilitation evaluation of cardiovascular and cerebrovascular diseases. All kinds of diseases of the carotid artery are related to the stiffness of the blood vessel, such as atherosclerosis and vascular plaques.

[0003] In the current technical solutions, the strain value of the blood vessel wall can be calculated based on ultrasonic imaging technology, and the strain performance exhibited by the blood vessel wall is characterized by the strain value, thereby intuitively reflecting the stiffness of the blood vessel. However, in the current solutions, when calculating the strain value of the blood vessel wall, the strain value is unstable and the repeatability is poor, resulting in unsatisfactory measurement results. In this regard, new technical solutions need to be proposed. Summary of the Invention

[0004] The main technical problem to be solved by this application is that the measurement of the strain value of the blood vessel wall is unstable and the repeatability is poor.

[0005] According to a first aspect, in one embodiment, a method for measuring vascular strain is provided, including:

[0006] Controlling the emission of a first ultrasound and a second ultrasound to a tissue containing a target blood vessel, and acquiring the ultrasound echo signal of the first ultrasound and the ultrasound echo signal of the second ultrasound;

[0007] Obtaining a set of ultrasound images of the target blood vessel over a period of time according to the ultrasound echo signal of the first ultrasound, the set of ultrasound images including multiple frames of ultrasound images, and the ultrasound images being used to reflect the tissue structure of the target blood vessel; and obtaining the blood flow velocity of the target blood vessel over the period of time according to the ultrasound echo signal of the second ultrasound;

[0008] Determining a first blood flow velocity and a second blood flow velocity from the blood flow velocity of the target blood vessel over the period of time based on a preset rule, and acquiring a first time point corresponding to the first blood flow velocity over the period of time and a second time point corresponding to the second blood flow velocity over the period of time; the preset rule includes that the magnitudes of the first blood flow velocity and the second blood flow velocity satisfy a preset velocity condition;

[0009] Obtain a set of target ultrasound images that are temporally between the first time point and the second time point from the set of ultrasound images, and measure the strain value of the target blood vessel based on the set of target ultrasound images.

[0010] According to a second aspect, an embodiment provides a method for measuring blood vessel strain, including:

[0011] Obtain a set of ultrasound images including a target blood vessel within a period of time, where the set of ultrasound images includes multiple frames of ultrasound images;

[0012] Obtain the value of a characteristic quantity within the period of time, where the characteristic quantity can characterize the periodic law of the blood vessel wall of the target blood vessel changing with time due to the periodic contraction and relaxation of the heart;

[0013] Determine a first parameter value and a second parameter value from the values of the characteristic quantity within the period of time based on a preset rule, and obtain a first time point corresponding to the first parameter value within the period of time and a second time point corresponding to the second parameter value within the period of time; the preset rule includes that the magnitudes of the first parameter value and the second parameter value satisfy a preset parameter condition;

[0014] From the set of ultrasound images, obtain a set of target ultrasound images that are temporally between the first time point and the second time point, and measure the strain value of the target blood vessel based on the set of target ultrasound images.

[0015] According to a third aspect, an embodiment provides an ultrasound imaging device, including:

[0016] An ultrasound probe for emitting ultrasonic waves into an area of interest in a biological tissue and receiving echo signals of the ultrasonic waves;

[0017] A transmit / receive control circuit for controlling the ultrasound probe to emit ultrasonic waves into the area of interest and receive the echo signals of the ultrasonic waves;

[0018] A human-computer interaction device for receiving user input and outputting visualization information;

[0019] A processor for implementing the method described in the first aspect or the second aspect.

[0020] According to a fourth aspect, an embodiment provides a computer-readable storage medium, on which a program is stored, and the program can be executed by a processor to implement the method described in the first aspect or the second aspect.

[0021] According to the blood vessel strain measurement method of the above embodiments, when determining the first blood flow velocity and the second blood flow velocity from the blood flow velocity based on a preset rule, the first blood flow velocity and the second blood flow velocity selected each time can be made relatively fixed, and the relatively fixed first blood flow velocity and second blood flow velocity can characterize the target blood vessel with a relatively fixed strain state. Therefore, when determining the first time point and the second time point within a period of time based on the relatively fixed first blood flow velocity and second blood flow velocity, and obtaining the target ultrasound image set that is located between the first time point and the second time point in terms of acquisition time in the ultrasound image set, it is equivalent to selecting the ultrasound images corresponding to the blood vessels with a relatively fixed strain state, and these images can be used as the initial frames for calculating the strain value. Since a relatively fixed ultrasound image can be selected each time to be used as the initial frame for calculating the strain value, the calculated strain value is relatively stable and has good repeatability, thereby improving the measurement effect of the strain value of the target blood vessel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 FIG. is a schematic structural diagram of an ultrasonic imaging device according to an embodiment;

[0023] Figure 2 FIG. is a schematic diagram of a blood flow velocity according to an embodiment;

[0024] Figure 3 FIG. is a schematic diagram of strain value measurement according to an embodiment;

[0025] Figure 4 FIG. is a schematic diagram of simultaneously displaying blood flow velocity and strain value according to an embodiment;

[0026] Figure 5 FIG. is a schematic flowchart of a blood vessel strain measurement method according to an embodiment;

[0027] Figure 6 FIG. is a schematic flowchart of a blood vessel strain measurement method according to another embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The present application will be further described in detail below in conjunction with the specific embodiments and the accompanying drawings. Similar elements in different embodiments are labeled with related similar element numbers. In the following embodiments, many detailed descriptions are provided to enable a better understanding of the present application. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present application are not shown or described in the specification to avoid overshadowing the core part of the present application. For those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0029] In addition, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can also be reordered or adjusted in a manner obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for clearly describing a certain embodiment and do not mean that they are the necessary sequences, unless it is stated otherwise that a certain sequence must be followed.

[0030] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the described objects and do not have any sequential or technical meaning. The "connection" and "coupling" mentioned in the present application, unless otherwise specified, both include direct and indirect connection (coupling).

[0031] In the current technical solution, after obtaining the ultrasonic video of the blood vessel, a random frame of the ultrasonic image is used as the initial frame for calculating the strain value, and then the strain value is calculated frame by frame within a certain cardiac cycle. However, there is a certain amount of motion accumulation in the blood vessel wall, resulting in different calculated strain results due to the motion accumulation of the blood vessel wall when using ultrasonic images corresponding to blood vessels in different strain states as the initial frame. When randomly selecting a frame of ultrasonic image as the initial frame for calculating the strain value, it is impossible to ensure that the blood vessels corresponding to the selected ultrasonic images are in the same strain state or similar strain states each time, resulting in unstable strain values and poor repeatability.

[0032] In some embodiments of the present application, when acquiring an ultrasonic image set of a target blood vessel over a period of time, the blood flow velocity of the target blood vessel over the period of time is also acquired, and there is a certain correlation between the blood flow velocity of the target blood vessel and the strain state of the target blood vessel. Therefore, based on the blood flow velocity of the target blood vessel, it is possible to avoid randomly selecting ultrasonic images from the ultrasonic image set. When determining a first blood flow velocity and a second blood flow velocity from the blood flow velocity based on a preset rule, the first blood flow velocity and the second blood flow velocity selected each time can be made relatively fixed, and the relatively fixed first blood flow velocity and second blood flow velocity can characterize the target blood vessel with a relatively fixed strain state. Therefore, when determining a first time point and a second time point within the period of time based on the relatively fixed first blood flow velocity and second blood flow velocity, and acquiring the target ultrasonic image set whose acquisition time is between the first time point and the second time point from the ultrasonic image set, it is equivalent to selecting the ultrasonic images corresponding to the blood vessels with a relatively fixed strain state, and these images can be used as the initial frames for calculating the strain value. Therefore, compared with randomly selecting an ultrasonic image as the initial frame for calculating the strain value in the prior art, since a relatively fixed ultrasonic image can be selected each time in the present application for use as the initial frame for calculating the strain value, the calculated strain value is relatively stable and has good repeatability, thereby improving the measurement effect of the strain value of the target blood vessel.

[0033] Some embodiments provide an ultrasonic imaging device that can be used to measure the strain value of a target blood vessel and make the measured strain value have good repeatability, thereby improving the measurement effect. Please refer to Figure 1 , the ultrasonic imaging device includes an ultrasonic probe 10, a transmit / receive control circuit, a processor 20, a human-machine interaction device 70, and a memory 80, which will be specifically described below.

[0034] The ultrasonic probe 10 is used to transmit ultrasonic waves into the region of interest in the biological tissue and receive the echo signals of the corresponding ultrasonic waves. The ultrasonic probe 10 includes a transducer (not shown in the figure) composed of a plurality of arrayed elements. The elements are used to transmit ultrasonic waves according to the excitation electrical signal or convert the received ultrasonic waves into electrical signals. Therefore, each element can be used to realize the mutual conversion between the electrical pulse signal and the ultrasonic wave, so as to transmit ultrasonic waves into the biological tissue of the scanning object, and it can also be used to receive the echo of the ultrasonic wave reflected by the tissue.

[0035] The transmit / receive control circuit is used to control the probe to transmit ultrasonic waves and receive the echo signals of the ultrasonic waves. The transmit / receive control circuit may include a transmit circuit 30 and a receive circuit 40. The transmit circuit 30 is used to, according to the control of the processor 20, excite the ultrasonic probe 10 to transmit ultrasonic waves to the scanning object, and the receive circuit 40 is used to receive the ultrasonic echo returned from the scanning object through the ultrasonic probe 10 to obtain the echo signal of the ultrasonic wave, and can also process the echo signal of the ultrasonic wave.

[0036] The human - machine interaction device 70 is used for human - machine interaction, such as outputting visual information and receiving user input. The ways to receive user input can include a keyboard, operation buttons, a mouse, a trackball, a touchpad, etc., or a touch screen integrated with a display; the ways to output visual information can include a display, a touch - display, a display screen, a touch - display screen, etc. In some embodiments, there can be two displays. One is the main screen, which can be used to display the processing results of ultrasonic echo signals, such as displaying ultrasonic images and the recognition results of ultrasonic images. The other is the secondary screen, which can be used to control the parameters of the ultrasonic imaging device, such as controlling the selection of the ultrasonic probe 10, ultrasonic modes, etc. It can be understood that part or all of the content displayed on the main screen and the secondary screen can be exchanged.

[0037] The memory 80 is used for storing various types of data.

[0038] Please refer to Figure 1 , the ultrasonic imaging device may further include a beamforming module 50 and an IQ demodulation module 60.

[0039] The beamforming module 50 is signal - connected to the receiving circuit 40 and is used for performing beamforming processing such as corresponding delay and weighted summation on the echo signal. Since the distances from the ultrasonic receiving points in the tissue to be measured to the receiving array elements are different, the channel data of the same receiving point output by different receiving array elements have a delay difference. Therefore, delay processing is required to align the phases and perform weighted summation on the different channel data of the same receiving point to obtain the ultrasonic image data after beamforming. The ultrasonic image data output by the beamforming module 50 is also called radio - frequency data (RF data). The beamforming module 50 outputs the RF data to the IQ demodulation module 60. In some embodiments, the beamforming module 50 can also output the RF data to the memory 80 for caching or saving, or directly output the RF data to the processor 20 for image processing.

[0040] The beamforming module 50 can execute the above - mentioned functions in a hardware, firmware, or software manner. The beamforming module 50 can be integrated in the processor 20 or can be set separately, and this application does not make a limitation.

[0041] The IQ demodulation module 60 removes the signal carrier through IQ demodulation, extracts the tissue structure information contained in the signal, and filters out noise. The signal obtained at this time is called the baseband signal (IQ data pair). The IQ demodulation module 60 outputs the IQ data pair to the processor 20 for image processing. In some embodiments, the IQ demodulation module 60 also outputs the IQ data pair to the memory 80 for caching or saving so that the processor 20 can read the data from the memory 80 for subsequent image processing.

[0042] The IQ demodulation module 60 can also perform the above functions in hardware, firmware, or software. Similarly, the IQ demodulation module 60 can be integrated into the processor 20 or set separately, and this application does not make any limitations.

[0043] The processor 20 is configured to be a central controller circuit (CPU) capable of processing input data according to specific logical instructions, one or more microprocessors 20, a graphics controller circuit (GPU), or any other electronic component, which can execute control over peripheral electronic components according to input instructions or predefined instructions, or perform data reading and / or saving on the memory 80, and can also process input data by executing programs in the memory 80. For example, according to one or more working modes, one or more processing operations are performed on the collected ultrasonic data. The processing operations include, but are not limited to, adjusting or defining the form of the ultrasonic waves emitted by the ultrasonic probe 10, generating various image frames for subsequent display on the display of the human-machine interaction device 70, or adjusting or defining the content and form displayed on the display, or adjusting one or more image display settings (such as ultrasonic images, interface components, positioning of regions of interest) displayed on the display.

[0044] When the echo signal is received, the collected ultrasonic data can be processed in real time by the processor 20 during scanning, or can be temporarily stored on the memory 80 and processed in a quasi-real-time manner in online or offline operations.

[0045] In this embodiment, the processor 20 controls the operation of the transmitting circuit 30 and the receiving circuit 40. For example, it controls the transmitting circuit 30 and the receiving circuit 40 to work alternately or simultaneously. The processor 20 can also determine a suitable working mode according to the user's selection or the program setting, form a transmission sequence corresponding to the current working mode, and send the transmission sequence to the transmitting circuit 30 so that the transmitting circuit 30 can control the ultrasonic probe 10 to emit ultrasonic waves using the appropriate transmission sequence.

[0046] The above are some descriptions of the ultrasonic imaging device. The following specifically describes the process of measuring vascular strain of the ultrasonic imaging device.

[0047] The processor controls the ultrasonic probe to emit a first ultrasonic wave and a second ultrasonic wave to the tissue containing the target blood vessel, and acquires the ultrasonic echo signal of the first ultrasonic wave and the ultrasonic echo signal of the second ultrasonic wave. Among them, an ultrasonic image set of the target blood vessel within a period of time is obtained based on the ultrasonic echo signal of the first ultrasonic wave. For example, an ultrasonic image set or an ultrasonic video about 1.5 - 3 s is acquired, and the ultrasonic image is used to reflect the tissue structure of the target blood vessel. For example, the first ultrasonic wave is emitted by the ultrasonic probe based on the first mode, and the first mode can be the B mode (brightness imaging mode), so that the position of the target blood vessel can be identified based on the ultrasonic image. The blood flow velocity of the target blood vessel within the period of time is obtained based on the ultrasonic echo signal of the second ultrasonic wave. For example, the second ultrasonic wave is emitted by the ultrasonic probe based on the second mode, and the second mode can be the C mode (color Doppler imaging mode) or the D mode (spectral Doppler imaging mode), so that the blood flow velocity of the target blood vessel can be acquired. In some embodiments, the blood flow velocity can also be calculated based on vector flow imaging, and vector flow imaging can be realized by methods such as multi-angle scanning transmission and reception, speckle tracking method or transverse wave oscillation.

[0048] In some embodiments, the processor can control the ultrasonic probe to combine the emission and echo reception of the first ultrasonic wave and the second ultrasonic wave, such as performing multi-modal imaging of the first mode and the second mode. The processor can also control different ultrasonic probes to separately emit and receive the first ultrasonic wave and the second ultrasonic wave.

[0049] In the above embodiments, the position of the target blood vessel can be identified based on the ultrasonic image set, so as to calculate the strain value of the target blood vessel. However, if the initial frame of the ultrasonic image is randomly selected from the ultrasonic image set, it will lead to unstable measurement of the strain value and poor repeatability.

[0050] In this regard, for the ultrasonic echo signals based on the first ultrasound and the second ultrasound in this application, the position of the target blood vessel and the blood flow velocity of the target blood vessel can be respectively obtained within the same time period. Since blood flow, as a moving medium in direct contact with the vessel wall, is the main factor causing the movement of the vessel wall, and the blood flow velocity affects the degree of vessel wall deformation, the strain of the blood vessel is mainly the strain performance exhibited by the vessel wall under the action of blood movement. There is a correlation between the blood flow velocity of the target blood vessel and the strain of the target blood vessel. Moreover, the blood flow velocity is mainly generated based on the contraction and relaxation of the heart. Therefore, the periodic contraction and relaxation of the heart will cause periodic changes in the blood flow velocity, which in turn causes periodic changes in the strain of the target blood vessel. During this periodic change process, at the same periodic position in different cycles, the blood flow velocity of the target blood vessel is basically the same, and the strain state of the target blood vessel is also basically the same. In this regard, the strain state of the target blood vessel can be characterized based on the blood flow velocity of the target blood vessel, and the time point corresponding to the strain state of the target blood vessel can be determined based on the time point of the blood flow velocity. In some embodiments, the state of the heart during the cardiac cycle can also be characterized based on the blood flow velocity of the target blood vessel. For example, when the blood flow velocity is relatively large, it characterizes the contraction state of the heart, and when the blood flow velocity is relatively small, it characterizes the relaxation state of the heart.

[0051] Therefore, when calculating the strain value of the target blood vessel, this application can select the strain state of the target blood vessel based on the blood flow velocity, so that the initial frame of the ultrasonic image and the termination frame of the ultrasonic image corresponding to the target blood vessel in the same strain state or a similar strain state can be selected according to the time point of the blood flow velocity. Therefore, compared with randomly selecting the initial frame of the ultrasonic image in the prior art, this application can select relatively fixed initial and termination frames of the ultrasonic image, making the strain states of the corresponding target blood vessels in the same strain state or a similar strain state. Under the accumulation of the movement of the vessel wall, based on the initial frame and the termination frame of the ultrasonic image corresponding to the target blood vessel in the same strain state or a similar strain state, the calculated strain value can tend to be stable, thus showing good repeatability. In some embodiments, the same state or a similar state of the heart during the cardiac cycle can be selected based on the blood flow velocity, so that the initial frame of the ultrasonic image corresponding to the target blood vessel when the heart is in the same state or a similar state can be selected according to the time point of the blood flow velocity.

[0052] The process of selecting the initial frame and the termination frame of the ultrasonic image will be specifically described below.

[0053] Please refer to Figure 2, which shows the blood flow velocity of the target blood vessel over a period of time. The processor determines a first blood flow velocity and a second blood flow velocity from the blood flow velocity of the target blood vessel over this period of time based on a preset rule, and obtains a first time point corresponding to the first blood flow velocity over this period of time and a second time point corresponding to the second blood flow velocity over this period of time. In this embodiment, in order to make the strain state of the target blood vessel in the same strain state or a similar strain state, when determining the first blood flow velocity and the second blood flow velocity from the blood flow velocity, it is necessary to make the determined first blood flow velocity and second blood flow velocity in relatively fixed positions during the periodic change. Therefore, the first blood flow velocity and the second blood flow velocity can be determined based on a certain preset rule. When the preset rule remains basically unchanged, the determined first blood flow velocity and second blood flow velocity are based on relatively fixed positions during the periodic change. In some embodiments, the preset rule may include that the magnitudes of the first blood flow velocity and the second blood flow velocity satisfy a preset velocity condition. In some embodiments, the preset rule may further include that the interval duration between the first time point and the second time point satisfies a preset duration condition. Among them, based on the preset velocity condition, the magnitude of the blood flow velocity can be restricted so that the first blood flow velocity and the second blood flow velocity are always in a relatively fixed range, and the first blood flow velocity and the second blood flow velocity will also always be at relatively fixed time points, so that the interval duration between the first time point and the second time point can be used to calculate the strain value. And based on the preset duration condition, the magnitude of the duration required for calculating the strain value can be further restricted so that the interval duration between the first blood flow velocity and the second blood flow velocity satisfies a certain cycle duration for calculating the strain value.

[0054] In some embodiments, during the process of the periodic change of the blood flow velocity caused by the periodic contraction and relaxation of the heart, its periodicity is mainly reflected in that when the heart contracts, the blood flow velocity is relatively large, and when the heart relaxes, the blood flow velocity is relatively small. Therefore, when determining the first blood flow velocity and the second blood flow velocity, the preset velocity condition can be configured so that among the blood flow velocities over this period of time, the velocity values of the first blood flow velocity and the second blood flow velocity are greater than the velocity values of the blood flow velocities at the first preset ratio. Or, configure the preset velocity condition so that among the blood flow velocities over this period of time, the velocity values of the first blood flow velocity and the second blood flow velocity are less than the velocity values of the blood flow velocities at the second preset ratio. Thus, during the periodic change of the blood flow velocity, the first blood flow velocity and the second blood flow velocity with obvious periodic characteristics can be determined, so that the determined first blood flow velocity and second blood flow velocity are in relatively fixed positions during the periodic change.

[0055] In some embodiments, the first preset ratio and the second preset ratio are preset. For example, the preset first preset ratio or the second preset ratio can be from seventy percent to ninety percent, or can be greater than or equal to sixty percent, or can also be greater than fifty percent, etc. The first preset ratio or the second preset ratio can be the same or different.

[0056] In other embodiments, the first preset ratio and the second preset ratio are automatically determined according to user data. For example, the first preset ratio and the second preset ratio are automatically determined according to the collected ultrasonic data.

[0057] In some embodiments, the first preset ratio can be from seventy percent to ninety percent, so that the velocity values of the first blood flow velocity and the second blood flow velocity are greater than most of the blood flow velocities. For example, the first blood flow velocity and the second blood flow velocity are near the peak of the blood flow velocity. In some embodiments, the second preset ratio can be from seventy percent to ninety percent, so that the velocity values of the first blood flow velocity and the second blood flow velocity are less than most of the blood flow velocities. For example, the first blood flow velocity and the second blood flow velocity are near the trough of the blood flow velocity.

[0058] In some embodiments, when the processor determines the first blood flow velocity and the second blood flow velocity, it can configure preset velocity conditions so that in the blood flow velocities during this period of time, the first blood flow velocity is the first maximum value and the second blood flow velocity is the second maximum value. Or configure preset velocity conditions so that in the blood flow velocities during this period of time, the first blood flow velocity is the first minimum value and the second blood flow velocity is the second minimum value. In this embodiment, during the process of the periodic contraction and relaxation of the heart resulting in the periodic change of the blood flow velocity, the blood flow velocity usually has a peak and a trough in a change cycle, and the peak and trough of the blood flow velocity can better characterize the strain state of the target blood vessel. For example, the peak and trough of the blood flow velocity can characterize the starting point of the strain of the target blood vessel in a cycle change, and the peak and trough of the blood flow velocity in the next cycle change can characterize the termination point of the end of the strain of the target blood vessel. In some embodiments, the peak and trough of the blood flow velocity can also better characterize the systolic state and diastolic state of the heart.

[0059] Therefore, when the first blood flow velocity is at the first maximum value and the second blood flow velocity is at the second maximum value, the first blood flow velocity sum can be one of the peaks in two change cycles, and the second blood flow velocity can be the other peak in the two change cycles. When the first blood flow velocity is at the first minimum value and the second blood flow velocity is at the second minimum value, the first blood flow velocity can be one of the troughs in the two change cycles, and the second blood flow velocity can be the other trough in the two change cycles, so that the determined first blood flow velocity and second blood flow velocity are at fixed positions in the periodic change. Among them, the two change cycles can be adjacent cycles or non - adjacent cycles. At the same time, when the first blood flow velocity and the second blood flow velocity are at the maximum value or the minimum value, the first blood flow velocity and the second blood flow velocity are basically the starting point and the ending point of a change cycle of the blood flow velocity respectively, and are also basically the starting point and the ending point of a change cycle of the strain of the target blood vessel respectively. At this time, determining the first time point and the second time point based on the first blood flow velocity and the second blood flow velocity can enable the calculation of the strain value of the target blood vessel to be completed within one or more complete change cycles, which can not only make the strain value of the target blood vessel have better repeatability, but also make the calculated strain value more accurate.

[0060] In some embodiments, when the processor determines the interval duration between the first time point and the second time point, it can configure a preset duration condition such that the interval duration is greater than 1 / 2, 2 / 3, 3 / 4 or 4 / 5 of the first cycle. Or, the interval duration is less than 6 / 5, 5 / 4, 4 / 3 or 3 / 2 of the first cycle. Or, the interval duration is greater than 1 / 2, 2 / 3, 3 / 4 or 4 / 5 of the first cycle and less than 6 / 5, 5 / 4, 4 / 3 or 3 / 2 of the first cycle. Or, the interval duration is an integer multiple of the first cycle, such as one first cycle or multiple first cycles. Among them, the first cycle is the cycle of the blood velocity in the target blood vessel or the cardiac cycle. Since the periodic contraction and relaxation of the heart will cause periodic changes in the blood flow velocity, the cycle of the blood velocity is basically the same as the cardiac cycle. In this embodiment, configuring the preset duration condition can avoid the interval duration between the first time point and the second time point being too small or too large, thus affecting the calculation of the strain value. At the same time, it can also limit the interval duration within a more appropriate range to facilitate the calculation of the strain value. Please refer to Figure 2 , which represents the blood flow velocity curve from time T1 to time T2. The blood flow velocity corresponding to the dashed line HR is the first blood flow velocity, and the blood flow velocity corresponding to the dashed line HR’ is the second blood flow velocity.

[0061] In some embodiments, when the processor obtains the first time point corresponding to the first blood flow velocity within the period of time and the second time point corresponding to the second blood flow velocity within the period of time, it may respectively obtain the acquisition times of the ultrasonic images corresponding to the first blood flow velocity and the second blood flow velocity, and use them as the first time point and the second time point respectively. Among them, the first time point and the second time point may be relative times within the period of time, such as the 0.1 second within the period of time, or absolute times, such as a certain hour, minute, and second.

[0062] In some embodiments, a set of target ultrasonic images located between the first time point and the second time point in terms of time is obtained from the set of ultrasonic images corresponding to the first ultrasound. When the first time point and the second time point respectively correspond to the time of a certain ultrasonic image in the set of ultrasonic images, that is, they respectively correspond to the times of the two ultrasonic images at both ends of the time in the set of target ultrasonic images. At this time, these two ultrasonic images are respectively the initial ultrasonic image frame and the terminal ultrasonic image frame, and the set of target ultrasonic images includes these two ultrasonic images and the ultrasonic images between the two ultrasonic images. In some embodiments, when the first time point and the second time point do not correspond to the time of a certain ultrasonic image in the set of ultrasonic images, ultrasonic images corresponding to other time points near the first time point and the second time point may be obtained and used as the two ultrasonic images at both ends of the time in the set of target ultrasonic images. By obtaining a set of target ultrasonic images including the initial ultrasonic image frame and the terminal ultrasonic image frame, the strain value of the target blood vessel can be measured.

[0063] The above is some description of the process of obtaining the set of target ultrasonic images. The following specifically describes the process of measuring the strain value of the target blood vessel.

[0064] After the processor obtains the set of target ultrasonic images based on the first time point and the second time point, it may use the initial ultrasonic image frame or the terminal ultrasonic image frame in the set of target ultrasonic images as the reference target ultrasonic image. Then, the position of the target blood vessel in the reference target ultrasonic image is obtained, and the position changes of the target blood vessel in other target ultrasonic images relative to this position are respectively obtained, so as to respectively determine the strain values of the target blood vessel in the corresponding target ultrasonic images according to each position change. In some embodiments, since the set of target ultrasonic images is relatively fixed, any ultrasonic image in the set of target ultrasonic images may also be used as the reference target ultrasonic image. For example, the ultrasonic image in the middle of the first time point and the second time point is used as the reference target ultrasonic image.

[0065] In some embodiments, when the processor obtains the position of the target blood vessel in the reference target ultrasound image, it may output an initial result of the target blood vessel wall based on the blood vessel segmentation model. Among them, the blood vessel segmentation model can automatically segment the target blood vessel area based on deep learning or traditional image processing algorithms. For example, taking the image of the target blood vessel currently scanned as the input, a deep learning model is constructed. Deep learning is not limited to the following typical deep learning convolutional networks, such as AlexNet, Resnet, VGG, etc. Then, the error between the model output and the manual annotation (the manual annotation is the binary label matrix of the target blood vessel area in the scanned image) is calculated through the segmentation loss function, and the deep learning model is trained to gradually reduce the error between the model output and the manual annotation, and finally a model that can normally segment the target blood vessel area is obtained. For other target ultrasound images, the movement of the target blood vessel wall can be tracked based on the target tracking algorithm to obtain the recognition result of the target blood vessel wall in other target ultrasound images, and the position change of the target blood vessel in other target ultrasound images relative to the target blood vessel in the reference target ultrasound image is obtained, and the strain value of the target blood vessel in the corresponding target ultrasound image is determined based on this position change. For example, for one of the target ultrasound images, if the change in the position of its target blood vessel relative to the position of the target blood vessel in the reference target ultrasound image is greater, then the strain value of the target blood vessel in this one of the target ultrasound images is greater, and vice versa.

[0066] In some embodiments, the target tracking algorithm can be a deep learning or traditional machine learning algorithm. For example, taking the video of the target blood vessel currently scanned as the input, the target blood vessel wall area is matched frame by frame through the target tracking algorithm to obtain the relative displacement of the corresponding tissues of the target blood vessel wall in two adjacent frames. The method is not limited to the following typical target tracking and monitoring algorithms, such as GMM, optical flow, Kalman filter, etc. The recognition result of the target blood vessel wall in adjacent frames is obtained based on this relative displacement. In some embodiments, limited by the frame rate of the ultrasound image and the quality of the target blood vessel ultrasound imaging, it is easy to generate errors at large deformation areas only by the method of the target tracking algorithm, and during the continuous tracking of the blood vessel in the ultrasound image, the errors are easy to accumulate. In this regard, the final wall recognition result can be obtained by combining blood vessel segmentation and target tracking. For example, when the displacement change of some tissues between two frames of ultrasound images exceeds the first threshold, or the difference between the coordinates of the target tracking result of the current frame ultrasound image and the coordinates of the target blood vessel segmentation result of the current frame exceeds the second threshold, it is considered that the tracking of these tissue parts is abnormal. At this time, the segmentation result of the current frame ultrasound image can be used for correction. By means of frame-by-frame tracking and segmentation correction, the wall recognition result of each frame of ultrasound image is improved.

[0067] In some embodiments, when the processor determines the strain values of the target blood vessels in the corresponding target ultrasound images according to the respective position changes, it obtains the corresponding coordinates of all the target blood vessel wall recognition results and inputs them into the strain calculation formula to respectively obtain the strain results of the target blood vessels in all the ultrasound images in the target ultrasound image set with respect to the target blood vessels in the reference target ultrasound image. In some embodiments, the calculation of the strain can be obtained according to the length change of the target blood vessel wall in the long axis direction, where the calculation of the long axis parameter of the target blood vessel is obtained according to the length change of the line segments where each discrete tracking point on the wall is located. Please refer to Figure 3 , for example, the discrete tracking points include Pt 0 , Pt 1 …Pt N etc. And according to the positions of each tracking point on the blood vessel wall in each frame of image, multiple sub-line segments can be obtained, such as l 0 , l 1 …l N-1 etc. And calculate the lengths of the sub-line segments in the long axis direction of the blood vessel wall near the position of each tracking point. For example, the sub-line segment between the discrete tracking points Pt 0 and Pt 1 is the sub-line segment L 0 . Among them, the strain is a dimensionless quantity, and the strain is the ratio of two length quantities at different times. Therefore, the calculation of the strain can be obtained by calculating the lengths of the blood vessel wall in different directions. In one embodiment, according to the blood vessel wall recognition result in the reference target ultrasound image, the coordinates of all discrete tracking points in the reference target ultrasound image are obtained, and the lengths of the sub-line segments L 0 between all adjacent tracking points are calculated. Then, the lengths of the sub-line segments L corresponding to the adjacent tracking points in other target ultrasound images are respectively obtained, and the sub-line segment length L 0 and the sub-line segment length L are substituted into the following strain calculation formula:

[0068] E=(L - L 0 ) / L 0 ;

[0069] where E is the strain of a sub-line segment length L in other target ultrasound images with respect to the corresponding sub-line segment length L 0 . Then, based on the above formula, the strains of each sub-line segment in other target ultrasound images are sequentially obtained, and the average value is obtained as the strain of the final blood vessel wall in other target ultrasound images. Based on this strain, the corresponding strain value is obtained. In some embodiments, in addition to calculating the strain values of the target blood vessels in each target ultrasound image, the difference between the maximum strain value and the minimum strain value in the target ultrasound image set can also be calculated, and this difference is used as the reference strain value of the target blood vessel.

[0070] In some embodiments, the target blood vessel can be the blood vessel of any organ or any type of blood vessel, such as arteries and veins.

[0071] In some embodiments, the target blood vessel is preferably an artery or a blood vessel with a blood flow velocity greater than a certain threshold, or a blood vessel with a diameter greater than a certain diameter threshold, etc.

[0072] In some embodiments, the target blood vessels are preferably carotid arteries, aorta, and femoral arteries.

[0073] The above are some descriptions of measuring the strain value of the target blood vessel.

[0074] In some embodiments, the carotid artery is taken as an example of the target blood vessel for illustration. Among them, the carotid artery is the part connecting the heart and the blood vessels of the brain. Since the carotid artery is relatively close to the heart, the periodic change of its blood flow velocity is strongly consistent with the periodic contraction and relaxation of the heart. And the periodic change of the blood flow velocity makes the strain of the carotid artery also have a strong periodicity. For example, when the patient is in a supine position, the doctor uses an extracorporeal ultrasound probe to scan both carotid arteries of the patient, and places the probe statically at the common carotid artery about 1.5 mm away from the carotid bulb according to the long-axis or short-axis sectional angle, and obtains the ultrasound video of the patient's carotid artery for about 1.5 - 3 s in real time, and the cross-section and wall movement of the carotid artery can be observed.

[0075] In some embodiments, after the processor completes the measurement of the strain value of the target blood vessel, on the same time axis, it controls the human-machine interaction device to display on the same screen the blood flow velocity curve showing the change of the blood flow velocity at the target blood vessel over time, and the strain value curve showing the change of the strain value at the target blood vessel over time. Please refer to Figure 4 , which shows the blood flow velocity curve and the strain value curve from time T1 to time T2. Among them, the curve represented by the solid line is the blood flow velocity curve, and the curve represented by the spaced dots is the strain value curve. The time point corresponding to the dashed line HR is the first time point, and the time point corresponding to the dashed line HR' is the second time point. This strain value curve is based on the initial frame of the ultrasound image corresponding to the first time point as the reference target ultrasound image, so the strain value corresponding to the first time point is zero.

[0076] In some embodiments, the blood flow velocity curve and the strain value curve can be in different coordinate systems, but their horizontal axes can both be the time axis, so that the change trends of the blood flow velocity curve and the strain value curve based on time can be viewed on the same screen by aligning the time points on the time axis. In some embodiments, the blood flow velocity curve and the strain value curve can be in the same coordinate system, where the horizontal axis is the time axis and the vertical axis is the blood flow velocity - strain value, so that the blood flow velocity curve and the strain value curve can be more directly compared on the same screen in the same coordinate system.

[0077] Please refer to Figure 4, in some embodiments, due to the large tissue deformation of the target blood vessel, for example, the tissue deformation of the ultrasonic carotid artery blood vessel is large during actual movement, and it is easily affected by accidental factors such as the patient's breathing frequency and the stability of probe holding, which may cause certain fluctuations in the drawn strain value curve. Therefore, the strain value curve can be smoothed to filter out the data fluctuations caused by accidental factors and make the strain value curve more in line with the actual situation. At the same time, in order to prevent the reference strain value of the target blood vessel from changing, when smoothing the strain value curve, the maximum strain value and / or the minimum strain value in the strain value curve need to be retained to obtain the smoothed strain value curve. In some embodiments, the processor can also control the human-computer interaction device to display the smoothed strain value curve on the same time axis. Please refer to again Figure 4 , the curve represented by the spaced short dashes is the smoothed strain value curve. It can be seen that the strain value curve has large fluctuations, while the smoothed strain value curve is more in line with the actual situation.

[0078] , in some embodiments, the processor can also control the human-computer interaction device to highlight the blood flow velocity curve and / or the strain value curve between the first time point and the second time point in terms of time. For example, the blood flow velocity curve and / or the strain value curve between the first time point and the second time point can be marked by an ROI box or auxiliary dotted lines. For example, the blood flow velocity curve and / or the strain value curve can be highlighted by different colors, curve thicknesses, curve types, curve blinking, etc., so as to be clearly distinguished from the curves in other time periods. Please refer to Figure 4 , one of the embodiments is to highlight the blood flow velocity curve and the strain value curve between the first time point and the second time point by an ROI box.

[0079] , in some embodiments, the processor can also control the human-computer interaction device to display the ultrasonic image corresponding to the specified time period or strain value on the strain value curve. For example, when the user specifies a certain time period or strain value based on touch or pointer, the ultrasonic video or the set of ultrasonic image frames corresponding to the time period is displayed on the same screen or different screens, or the ultrasonic image frame corresponding to the strain value is displayed.

[0080] In the above embodiments, the blood flow velocity curve and the strain value curve are drawn in the same coordinate system, and the mechanical properties of the target blood vessel can be observed from two completely different perspectives of hemodynamics and image post-processing, which is convenient for discovering the strain laws presented by blood vessels with different stiffness degrees at different blood flow velocities.

[0081] The above is a process for measuring blood vessel strain based on blood flow velocity. The following specifically describes another process for measuring blood vessel strain.

[0082] The processor acquires a set of ultrasound images including the target blood vessel within a period of time, and the set of ultrasound images includes multiple frames of ultrasound images. In some embodiments, the processor may control the ultrasound probe to emit a first ultrasound to the tissue including the target blood vessel, acquire the ultrasound echo signal of the first ultrasound, and obtain the set of ultrasound images based on the ultrasound echo signal of the first ultrasound. In some embodiments, the processor may read the video data of a historical examination to obtain the set of ultrasound images.

[0083] The processor acquires the value of a feature quantity within the period of time, and the feature quantity can characterize the periodic law of the blood vessel wall of the target blood vessel changing with time due to the periodic contraction and relaxation of the heart. In some embodiments, the feature quantity includes at least one of the average diameter of the target blood vessel, the blood vessel area, the blood vessel volume, and the blood flow velocity. Since the periodic contraction and relaxation of the heart result in the periodic change of the blood flow velocity, the blood flow velocity of the target blood vessel can characterize the periodic law of the blood vessel wall of the target blood vessel changing with time due to the periodic contraction and relaxation of the heart. And the blood flow velocity is the moving medium in direct contact with the blood vessel wall, and blood flow is the main factor causing the movement of the blood vessel wall. Therefore, it is mainly the blood flow velocity that affects the degree of deformation of the blood vessel wall. When the blood vessel wall deforms, it will cause corresponding changes in the average diameter, blood vessel area, and blood vessel volume. Therefore, the average diameter, blood vessel area, and blood vessel volume can also characterize the periodic law of the blood vessel wall of the target blood vessel changing with time due to the periodic contraction and relaxation of the heart. For example, when the heart contracts, the blood flow velocity of the target blood vessel increases, resulting in the dilation of the blood vessel wall and corresponding increases in the average diameter, blood vessel area, and blood vessel volume. When the heart relaxes, the blood flow velocity of the target blood vessel decreases, resulting in the contraction of the blood vessel wall and corresponding decreases in the average diameter, blood vessel area, and blood vessel volume. And when the blood flow velocity reaches the maximum during heart contraction, the average diameter, blood vessel area, and blood vessel volume also basically reach the maximum. When the blood flow velocity reaches the minimum during heart relaxation, the average diameter, blood vessel area, and blood vessel volume also basically reach the minimum.

[0084] In some embodiments, the processor may emit a second ultrasound to the target blood vessel and obtain the value of the feature quantity according to the ultrasound echo signal of the second ultrasound. For example, the average diameter, blood vessel area, blood vessel volume, and blood flow velocity of the target blood vessel can be obtained. In some embodiments, when the first ultrasound and the second ultrasound are different ultrasounds, the first ultrasound and the second ultrasound are combinedly emitted and the echo is received by the same ultrasound probe, or the first ultrasound and the second ultrasound are respectively emitted and the echo is received by different ultrasound probes. For example, when the value of the feature quantity is the blood flow velocity. In some embodiments, when the first ultrasound and the second ultrasound are the same ultrasound, the first ultrasound and the second ultrasound are the same ultrasound emitted by the same ultrasound probe. For example, when the values of the feature quantity are the average diameter, blood vessel area, and blood vessel volume.

[0085] The processor determines a first parameter value and a second parameter value from the values of the feature quantity within the period based on a preset rule, and obtains a first time point corresponding to the first parameter value within the period and a second time point corresponding to the second parameter value within the period. Among them, the preset rule includes that the magnitudes of the first parameter value and the second parameter value satisfy a preset parameter condition, and the time interval duration between the first time point and the second time point satisfies a preset duration condition. In this embodiment, determining the first parameter value and the second parameter value from the values of the feature quantity can also be used to select the strain state of the target blood vessel, so that the initial frame and the termination frame of the ultrasound image corresponding to the target blood vessel in the same strain state or a similar strain state can be selected according to the time points of the parameter values. Under the accumulation of the movement of the blood vessel wall, based on the initial frame and the termination frame of the ultrasound image corresponding to the target blood vessel in the same strain state or a similar strain state, the calculated strain value can tend to be stable, thus showing good repeatability.

[0086] In some embodiments, when configuring the preset rule, the processor may adopt the preset rule for the processor to select the first blood flow velocity and the second blood flow velocity in the above embodiments, which will not be elaborated here. In some embodiments, when the feature quantity is the average diameter, the preset parameter condition includes: the first parameter value and the second parameter value are the maximum or minimum average diameter. When the feature quantity is the blood vessel area, the preset parameter condition includes: the first parameter value and the second parameter value are the maximum or minimum blood vessel area. When the feature quantity is the blood vessel volume, the preset parameter condition includes: the first parameter value and the second parameter value are the maximum or minimum blood vessel volume. When the feature quantity is the blood flow velocity, the preset parameter condition includes: the first parameter value and the second parameter value are the maximum or minimum blood flow velocity.

[0087] In some embodiments, the processor may obtain the cardiac cycle parameter values within a period of time, and delay the cardiac cycle parameter values to be used as the values of the characteristic quantities within the period of time. Due to the periodic contraction and relaxation of the heart, the blood flow velocity and the blood vessel wall of the target blood vessel change periodically. Therefore, the periodic law of the change of the blood vessel wall of the target blood vessel with time due to the periodic contraction and relaxation of the heart can also be directly characterized based on the cardiac cycle parameter values. However, after the heart completes contraction and relaxation, it is necessary to affect the change of the blood vessel wall based on the blood flow, and there is a certain delay in this process. Therefore, the cardiac cycle parameter values can be delayed to be used as the values of the characteristic quantities within the period of time. The delay is obtained based on the positional relationship between the target blood vessel and the heart. For example, the closer the distance between the target blood vessel and the heart, the smaller the delay, and vice versa. In some embodiments, the cardiac cycle parameter values may be electrocardiogram parameter values, and the electrocardiogram parameter values can characterize the periodic contraction and relaxation of the heart. At this time, the first parameter value and the second parameter value are the maximum or minimum values after the electrocardiogram parameter values are delayed.

[0088] The processor obtains a set of target ultrasound images based on a first time point and a second time point, measures the strain value of the target blood vessel based on the set of target ultrasound images, and simultaneously displays a parameter value curve of the change of the value of the characteristic quantity at the target blood vessel with time and a strain value curve of the change of the strain value at the target blood vessel with time. In some embodiments, when the processor obtains the set of target ultrasound images, measures the strain value of the target blood vessel, and displays the parameter value curve and the strain value curve, the processes in the above embodiments may be adopted, which will not be elaborated here.

[0089] The above is some description of the process of measuring blood vessel strain by an ultrasound imaging device. The following describes the strain measurement method.

[0090] In some embodiments, a blood vessel strain measurement method is provided, which can be applied to the above ultrasound imaging device. Please refer to Figure 5 , the blood vessel strain measurement method includes the following steps:

[0091] Step 100: Obtain a set of ultrasound images and the blood flow velocity of the target blood vessel. Control the emission of a first ultrasound and a second ultrasound to the tissue containing the target blood vessel, and obtain the ultrasound echo signal of the first ultrasound and the ultrasound echo signal of the second ultrasound; obtain a set of ultrasound images of the target blood vessel within a period of time according to the ultrasound echo signal of the first ultrasound, the set of ultrasound images includes multiple frames of ultrasound images, and the ultrasound images are used to reflect the tissue structure of the target blood vessel; and obtain the blood flow velocity of the target blood vessel within the period of time according to the ultrasound echo signal of the second ultrasound.

[0092] Step 200: Obtain a first time point and a second time point. Determine a first blood flow velocity and a second blood flow velocity from the blood flow velocities of the target blood vessel during the period based on a preset rule, and obtain the first time point corresponding to the first blood flow velocity during the period and the second time point corresponding to the second blood flow velocity during the period; the preset rule includes that the magnitudes of the first blood flow velocity and the second blood flow velocity satisfy a preset velocity condition.

[0093] Step 300: Obtain a set of target ultrasound images and measure the strain value. Obtain a set of target ultrasound images whose time positions are between the first time point and the second time point from the set of ultrasound images, and measure the strain value of the target blood vessel based on the set of target ultrasound images.

[0094] Step 400: Display the blood flow velocity and the strain value on the same screen. On the same time axis, display the blood flow velocity curve showing the change of the blood flow velocity of the target blood vessel over time, and display the strain value curve showing the change of the strain value of the target blood vessel over time.

[0095] In some embodiments, the preset velocity condition includes: among the blood flow velocities during the period, the velocity values of the first blood flow velocity and the second blood flow velocity are greater than the velocity values of the blood flow velocities at a first preset ratio; or, the velocity values of the first blood flow velocity and the second blood flow velocity are less than the velocity values of the blood flow velocities at a second preset ratio. In some embodiments, the first preset ratio is from seventy percent to ninety percent, and the second preset ratio is from seventy percent to ninety percent. In some embodiments, the preset velocity condition includes: the first blood flow velocity is a first maximum value and the second blood flow velocity is a second maximum value; or, the first blood flow velocity is a first minimum value and the second blood flow velocity is a second minimum value.

[0096] In some embodiments, the preset rule further includes that the time interval between the first time point and the second time point satisfies a preset time interval condition. In some embodiments, the preset time interval condition includes: the time interval is greater than 1 / 2, 2 / 3, 3 / 4, or 4 / 5 of a first period; and / or, the time interval is less than 6 / 5, 5 / 4, 4 / 3, or 3 / 2 of a first period; and / or, the time interval is an integer multiple of a first period; wherein, the first period is the period of the blood velocity in the target blood vessel, or the cardiac cycle.

[0097] In some embodiments, a blood vessel strain measurement method is provided, which can be applied to the above-mentioned ultrasound imaging device. Please refer to Figure 6 , and the blood vessel strain measurement method includes the following steps:

[0098] Step 110: Obtain an ultrasonic image set of the target blood vessel and the values of the characteristic quantities. Obtain an ultrasonic image set including the target blood vessel within a period of time, where the ultrasonic image set includes multiple frames of ultrasonic images; obtain the values of the characteristic quantities within the period of time, and the characteristic quantity can characterize the periodic law of the blood vessel wall of the target blood vessel changing with time due to the periodic contraction and relaxation of the heart.

[0099] Step 210: Obtain the first time point and the second time point. Determine a first parameter value and a second parameter value from the values of the characteristic quantities within the period of time based on a preset rule, and obtain the first time point corresponding to the first parameter value within the period of time and the second time point corresponding to the second parameter value within the period of time; the preset rule includes that the magnitudes of the first parameter value and the second parameter value satisfy a preset parameter condition. In some embodiments, the preset rule further includes that the time interval duration between the first time point and the second time point satisfies a preset duration condition.

[0100] Step 310: Obtain a target ultrasonic image set and measure the strain value. Obtain a target ultrasonic image set that is temporally between the first time point and the second time point from the ultrasonic image set, and measure the strain value of the target blood vessel based on the target ultrasonic image set.

[0101] Step 410: Display the characteristic quantity and the strain value on the same screen. On the same time axis, display a parameter value curve of the values of the characteristic quantity at the target blood vessel changing with time, and display a strain value curve of the strain value at the target blood vessel changing with time.

[0102] In some embodiments, a computer-readable storage medium is provided, and a program is stored on the medium, and the program can be executed by a processor to implement the above blood vessel strain measurement method.

[0103] Those skilled in the art can understand that all or part of the functions of the various methods in the above embodiments can be implemented by hardware or by computer programs. When all or part of the functions in the above embodiments are implemented by computer programs, the programs can be stored in a computer-readable storage medium, which can include: read-only memory, random access memory, magnetic disks, optical disks, hard disks, etc. The above functions can be realized by executing these programs on a computer. For example, store the program in the memory of the device, and when the processor executes the program in the memory, the above-mentioned all or part of the functions can be realized. In addition, when all or part of the functions in the above embodiments are implemented by computer programs, the programs can also be stored in storage media such as servers, other computers, magnetic disks, optical disks, flash drives or external hard drives, and saved to the memory of the local device by downloading or copying, or the system of the local device can be updated. When the processor executes the program in the memory, all or part of the functions in the above embodiments can be realized.

[0104] The above uses specific examples to elaborate on the present application, which is only for helping to understand the present application and is not intended to limit the present application. For those skilled in the technical field to which the present application pertains, based on the idea of the present application, several simple deductions, deformations or substitutions can also be made.

Claims

1. A method for measuring vascular strain, characterized in that: include: Controlling the emission of a first ultrasound and a second ultrasound to a tissue containing a target blood vessel, and acquiring an ultrasound echo signal of the first ultrasound and an ultrasound echo signal of the second ultrasound; Obtaining a set of ultrasound images of the target blood vessel within a period of time according to the ultrasound echo signal of the first ultrasound, wherein the ultrasound image set includes multiple frames of ultrasound images, and the ultrasound images are used to reflect the tissue structure of the target blood vessel; and obtaining a blood flow velocity of the target blood vessel within the period of time according to the ultrasound echo signal of the second ultrasound; Determining a first blood flow velocity and a second blood flow velocity from the blood flow velocities of the target blood vessel within the period of time based on a preset rule, and obtaining a first time point corresponding to the first blood flow velocity within the period of time and a second time point corresponding to the second blood flow velocity within the period of time; the preset rule includes that the magnitudes of the first blood flow velocity and the second blood flow velocity satisfy a preset velocity condition; A target ultrasound image set temporally located between the first time point and the second time point is acquired from the ultrasound image set, and a strain value of the target blood vessel is measured based on the target ultrasound image set.

2. The method for measuring blood vessel strain according to claim 1, characterized in that: The preset speed condition includes: among the blood flow velocities within the period of time, the speed values ​​of the first blood flow velocity and the second blood flow velocity are greater than the speed value of the blood flow velocity of a first preset ratio; or, the speed values ​​of the first blood flow velocity and the second blood flow velocity are less than the speed value of the blood flow velocity of a second preset ratio.

3. The method for measuring blood vessel strain according to claim 2, characterized in that: The first preset ratio is greater than fifty percent, or seventy percent to ninety percent, and the second preset ratio is greater than fifty percent, or seventy percent to ninety percent.

4. The method for measuring blood vessel strain according to any one of claims 1 to 3, characterized in that: The preset speed condition includes: the first blood flow speed is a first maximum value and the second blood flow speed is a second maximum value; or, the first blood flow speed is a first minimum value and the second blood flow speed is a second minimum value.

5. The method for measuring blood vessel strain according to claim 1, wherein: The preset rule also includes that the interval duration between the first time point and the second time point satisfies a preset duration condition.

6. The method for measuring blood vessel strain according to claim 5, characterized in that: The preset duration conditions include: the interval duration is greater than 1 / 2, 2 / 3, 3 / 4 or 4 / 5 of the first cycle; and / or the interval duration is less than 6 / 5, 5 / 4, 4 / 3 or 3 / 2 of the first cycle; and / or the interval duration is equal to an integer multiple of the first cycle; wherein the first cycle is the cycle of blood flow velocity in the target blood vessel, or the cardiac cycle.

7. The method for measuring blood vessel strain according to claim 1, characterized in that: The first blood flow velocity and the second blood flow velocity are used to characterize the same strain state or a similar strain state of the target blood vessel during the periodic change of the blood flow velocity; and / or, The first blood flow velocity and the second blood flow velocity are used to characterize the same state or a similar state of the heart in a cardiac cycle, and the same state is a diastolic state or a systolic state.

8. The method for measuring blood vessel strain according to any one of claims 1 to 7, characterized in that: The target blood vessel is an artery, and the target blood vessel is preferably a carotid artery, an aorta or a femoral artery.

9. The method for measuring blood vessel strain according to any one of claims 1 to 7, characterized in that: The first ultrasound and the second ultrasound are combinedly transmitted and echo received by the same ultrasound probe, or the first ultrasound and the second ultrasound are respectively transmitted and echo received by different ultrasound probes.

10. The method for measuring blood vessel strain according to any one of claims 1 to 7, characterized in that: The measuring the strain value of the target blood vessel based on the target ultrasound image set includes: Based on the first time point or the second time point, determining a corresponding reference target ultrasound image from the target ultrasound image set in time; The position of the target blood vessel in the reference target ultrasound image is obtained, and the position changes of the target blood vessels in other target ultrasound images relative to the position are respectively obtained, and the strain values ​​of the target blood vessels in the corresponding target ultrasound images are respectively determined according to the respective position changes.

11. The method for measuring blood vessel strain according to claim 10, characterized in that: Also includes: On the same time axis, a blood flow velocity curve showing the blood flow velocity at the target blood vessel changing with time and a strain value curve showing the strain value at the target blood vessel changing with time are displayed on the same screen.

12. The method for measuring blood vessel strain according to claim 11, characterized in that: Also includes: Smoothing the strain value curve, and retaining the maximum strain value and / or the minimum strain value in the strain value curve to obtain a smoothed strain value curve; and displaying the smoothed strain value curve on the same time axis; and / or, The blood flow velocity curve and / or the strain value curve temporally located between the first time point and the second time point is highlighted. and / or, Based on a time period or a strain value specified by a user on the strain value curve, the ultrasound image corresponding to the time period or the strain value is displayed.

13. A method for measuring blood vessel strain, characterized in that: include: Acquire a set of ultrasound images containing a target blood vessel within a period of time, wherein the set of ultrasound images includes multiple frames of ultrasound images; Acquire a value of a characteristic quantity within the period of time, wherein the characteristic quantity can characterize a periodic law of a change of a blood vessel wall of the target blood vessel over time due to periodic contraction and relaxation of the heart; Determine a first parameter value and a second parameter value from the value of the feature quantity within the period of time based on a preset rule, and obtain a first time point corresponding to the first parameter value within the period of time and a second time point corresponding to the second parameter value within the period of time; the preset rule includes that the magnitudes of the first parameter value and the second parameter value satisfy a preset parameter condition; A target ultrasound image set temporally located between the first time point and the second time point is acquired from the ultrasound image set, and a strain value of the target blood vessel is measured based on the target ultrasound image set.

14. The method for measuring blood vessel strain according to claim 13, characterized in that: The characteristic quantity includes at least one of the average diameter of the target blood vessel, the blood vessel area, the blood vessel volume, and the blood flow velocity; or, The cardiac cycle parameter values ​​within the period of time are acquired, and the cardiac cycle parameter values ​​are delayed to serve as the values ​​of the characteristic quantity within the period of time.

15. The blood vessel strain measurement method according to claim 14, characterized in that: When the characteristic quantity is an average pipe diameter, the preset parameter condition includes: the first parameter value and the second parameter value are a maximum value of the average pipe diameter or a minimum value of the average pipe diameter; When the characteristic quantity is the blood vessel area, the preset parameter condition includes: the first parameter value and the second parameter value are the maximum value or the minimum value of the blood vessel area; When the characteristic quantity is the blood vessel volume, the preset parameter conditions include: the first parameter value and the second parameter value are the maximum value of the blood vessel volume or the minimum value of the blood vessel volume; When the characteristic quantity is blood flow velocity, the preset parameter conditions include: the first parameter value and the second parameter value are a maximum value of blood flow velocity or a minimum value of blood flow velocity; or, The cardiac cycle parameter value includes an electrocardiogram parameter value, and the preset parameter condition includes: the first parameter value and the second parameter value are the maximum value or the minimum value of the electrocardiogram parameter value after delay.

16. The method for measuring blood vessel strain according to claim 13, characterized in that: The target blood vessel is an artery, and the target blood vessel is preferably a carotid artery; and / or, The preset rule also includes that the interval duration between the first time point and the second time point satisfies a preset duration condition, and the preset duration condition includes: the interval duration is greater than 1 / 2, 2 / 3, 3 / 4 or 4 / 5 of the first cycle; and / or the interval duration is less than 6 / 5, 5 / 4, 4 / 3 or 3 / 2 of the first cycle; and / or the interval duration is equal to an integer multiple of the first cycle; wherein the first cycle is the cycle of the characteristic quantity in the target blood vessel, or the cardiac cycle.

17. The method for measuring blood vessel strain according to claim 13, characterized in that: Based on transmitting a second ultrasound wave to the target blood vessel, and obtaining the value of the characteristic amount according to an ultrasound echo signal of the second ultrasound wave; Wherein, based on transmitting a first ultrasound to the target blood vessel, and obtaining the ultrasound image set according to an ultrasound echo signal of the first ultrasound, the first ultrasound and the second ultrasound are in the same or different modes; When the first ultrasound and the second ultrasound are different ultrasounds, the first ultrasound and the second ultrasound are combinedly transmitted and echo received by the same ultrasound probe, or the first ultrasound and the second ultrasound are respectively transmitted and echo received by different ultrasound probes; When the first ultrasound and the second ultrasound are the same ultrasound, the first ultrasound and the second ultrasound are the same ultrasound emitted by the same ultrasound probe.

18. The method for measuring blood vessel strain according to any one of claims 13 to 17, characterized in that: The measuring the strain value of the target blood vessel based on the target ultrasound image set includes: Based on the first time point or the second time point, determining a corresponding reference target ultrasound image from the target ultrasound image set in time; Acquire the position of the target blood vessel in the reference target ultrasound image, and respectively acquire the position changes of the target blood vessels in other target ultrasound images relative to the position, and determine the strain values ​​of the target blood vessels in the corresponding target ultrasound images according to the respective position changes; On the same time axis, a parameter value curve showing the change of the characteristic value at the target blood vessel over time and a strain value curve showing the change of the strain value at the target blood vessel over time are displayed on the same screen.

19. An ultrasonic imaging device, characterized in that: include: An ultrasonic probe, used for transmitting ultrasonic waves to a region of interest in biological tissue and receiving echo signals of the ultrasonic waves; A transmitting / receiving control circuit, used for controlling the ultrasonic probe to transmit ultrasonic waves to the region of interest and to receive echo signals of the ultrasonic waves; A human-computer interaction device for receiving user input and outputting visual information; A processor, configured to implement the method according to any one of claims 1 to 18.

20. A computer-readable storage medium, characterized in that: The medium stores a program, which can be executed by a processor to implement the method according to any one of claims 1 to 18.

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