CN117322905A

CN117322905A - Ultrasonic contrast imaging method and device, ultrasonic equipment and storage medium

Info

Publication number: CN117322905A
Application number: CN202210736704.XA
Authority: CN
Inventors: 朱建武; 刘旺锋; 冯乃章
Original assignee: Sonoscape Medical Corp
Current assignee: Sonoscape Medical Corp
Priority date: 2022-06-27
Filing date: 2022-06-27
Publication date: 2024-01-02
Also published as: WO2024001348A1

Abstract

The application discloses an ultrasonic contrast imaging method, an ultrasonic contrast imaging device, ultrasonic equipment and a readable storage medium, wherein the method comprises the following steps: determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe, and generating a pulse sequence containing a plurality of ultrasonic signal groups based on the plurality of transmitting frequencies; the ultrasonic signal group comprises a plurality of ultrasonic signals, and the ultrasonic signals at least comprise ultrasonic sub-signals with different periodic emission frequencies; sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in a pulse sequence, and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies; processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies, and generating corresponding contrast images based on the contrast signals; and fusing the contrast images to obtain a target contrast image. The requirements of penetrating power, sensitivity and resolution are simultaneously met through one-time radiography imaging.

Description

Ultrasonic contrast imaging method and device, ultrasonic equipment and storage medium

Technical Field

The present application relates to the field of ultrasound imaging, and more particularly, to an ultrasound contrast imaging method and apparatus, and an ultrasound device and a computer readable storage medium.

Background

In the current ultrasound imaging systems of each manufacturer, the contrast image provides a penetration/sensitivity mode Pen, a general mode Gen and a resolution mode Res, and the user can only select among the imaging modes provided by the manufacturer. However, because the physical conditions of different people are different, the attenuation of ultrasound and the like are different, so that a plurality of focuses with different forms exist simultaneously according to different focus characteristics such as the depth and the size of the focuses or the same section, a doctor can select one imaging mode according to experience, if a contrast image does not meet the expected requirement, for example, the resolution is insufficient, the sensitivity is insufficient or the penetration is insufficient, one imaging mode can be selected again for carrying out second contrast, particularly when the same section has a tiny focus and a focus with deeper depth, multiple times of contrast needs to be carried out under most conditions to observe good contrast perfusion conditions of a plurality of focuses. Thus, for some special scenes, the requirements of penetration, sensitivity and resolution cannot be met simultaneously through one-time contrast imaging, and at this time, the clinical time cost and the contrast agent cost are increased.

Therefore, how to simultaneously satisfy the requirements of penetration, sensitivity and resolution by one-time contrast imaging is a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

It is an object of the present application to provide an ultrasound contrast imaging method, apparatus and an ultrasound device and a computer readable storage medium, which simultaneously fulfil the requirements of penetration force, sensitivity and resolution by one contrast imaging.

To achieve the above object, the present application provides an ultrasound imaging method, including:

determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe, and generating a pulse sequence containing a plurality of ultrasonic signal groups based on the transmitting frequencies; each ultrasonic signal group comprises a plurality of ultrasonic signals, each ultrasonic signal at least comprises two ultrasonic sub-signals with different periodic emission frequencies, the emission frequencies of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and the emission frequencies of the corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different;

sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence, and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies;

Processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies, and generating corresponding contrast images based on the contrast signals;

and fusing the contrast images to obtain a target contrast image.

Wherein the determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe, generating a pulse sequence containing a plurality of ultrasonic signal groups based on a plurality of transmitting frequencies, comprises:

determining a reference transmission frequency and a target coefficient, determining the product of the reference transmission frequency and the target coefficient as a first transmission frequency, determining two times of the first transmission frequency as a second transmission frequency, determining three times of the first transmission frequency as a third transmission frequency, and determining four times of the first transmission frequency as a fourth transmission frequency; wherein the first transmitting frequency, the second transmitting frequency, the third transmitting frequency and the fourth transmitting frequency are all within the effective bandwidth range of the ultrasonic probe;

generating a pulse sequence comprising a first set of ultrasonic signals and a second set of ultrasonic signals; wherein the first set of ultrasonic signals is generated based on the first and second transmission frequencies and the second set of ultrasonic signals is generated based on the third and fourth transmission frequencies.

Wherein the sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence comprises:

determining different voltage amplitudes for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group;

determining the same number of transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group;

and sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence based on the transmission frequency, the voltage amplitude and the number of the transmission aperture array elements of different ultrasonic sub-signals in different ultrasonic signals.

Each ultrasonic signal group comprises a first ultrasonic signal and a second ultrasonic signal, correspondingly, the method for determining different voltage amplitudes for ultrasonic sub-signals with corresponding periods in different ultrasonic signals in the same ultrasonic signal group comprises the following steps:

determining a first voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and a second voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the second voltage amplitude is a preset multiple of the first voltage amplitude.

Wherein the second voltage amplitude is twice the first voltage amplitude.

Each ultrasonic signal group comprises a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, and correspondingly, the method for determining different voltage amplitudes for ultrasonic sub-signals with corresponding periods in different ultrasonic signals in the same ultrasonic signal group comprises the following steps:

determining a third voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and the third ultrasonic signal, and determining a fourth voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the fourth voltage amplitude is a preset multiple of the third voltage amplitude.

Wherein the fourth voltage amplitude is twice the third voltage amplitude.

determining the same voltage amplitude for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group;

determining different numbers of transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group;

Each ultrasonic signal group comprises a first ultrasonic signal and a second ultrasonic signal, and correspondingly, the determining of the number of different transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group comprises the following steps:

determining the number of first transmitting aperture array elements for ultrasonic sub-signals in the first ultrasonic signal, and determining the number of second transmitting aperture array elements for ultrasonic sub-signals in the second ultrasonic signal; the number of the array elements of the second transmitting aperture is a preset multiple of the number of the array elements of the first transmitting aperture.

The number of the array elements of the second transmitting aperture is twice that of the array elements of the first transmitting aperture.

Each ultrasonic signal group comprises a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, and correspondingly, the determining of the number of different transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group comprises the following steps:

determining a transmit aperture of an ultrasound sub-signal in the first ultrasound signal as one of an odd aperture or an even aperture, determining a transmit aperture of an ultrasound sub-signal in the second ultrasound signal as a full aperture, and determining a transmit aperture of an ultrasound sub-signal in the third ultrasound signal as the other of the odd aperture or the even aperture.

Processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies, including:

weighting echo signals of different ultrasonic signals in each ultrasonic signal group based on a voltage amplitude relation and a phase relation among different ultrasonic signals in each ultrasonic signal group to obtain contrast signals corresponding to each ultrasonic signal group;

and demodulating the contrast signals corresponding to each ultrasonic signal group by using demodulation circuits corresponding to different imaging frequencies to obtain the contrast signals corresponding to different imaging frequencies.

The weighting processing is performed on echo signals of different ultrasonic signals in each ultrasonic signal group based on a voltage amplitude relation and a phase relation between different ultrasonic signals in each ultrasonic signal group to obtain contrast signals corresponding to each ultrasonic signal group, and the weighting processing comprises the following steps:

determining a weighting coefficient of the corresponding echo signal based on a voltage amplitude relation between different ultrasonic signals in each ultrasonic signal group;

determining the operation relation of the corresponding echo signals based on the phase relation between different ultrasonic signals in each ultrasonic signal group; if the phase relations are opposite, the operation relations are addition, and if the phase relations are the same, the operation relations are subtraction;

And carrying out weighting processing based on the weighting coefficients and the operation relations of the echo signals of different ultrasonic signals in each ultrasonic signal group to obtain the contrast signals corresponding to each ultrasonic signal group.

Wherein the sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals comprises:

sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence so that contrast agent microbubbles generate fundamental wave signals corresponding to different first imaging frequencies, generating multiple harmonic signals corresponding to second imaging frequencies based on the fundamental wave signals corresponding to the first imaging frequencies, and generating differential harmonic signals corresponding to third imaging frequencies based on the fundamental wave signals corresponding to the different first imaging frequencies; wherein the second imaging frequency is an integer multiple of the first imaging frequency, and the third imaging frequency is at least one of a difference or a sum between different first imaging frequencies;

and receiving fundamental wave signals corresponding to the first imaging frequency, multiple harmonic signals corresponding to the second imaging frequency and differential harmonic signals corresponding to the third imaging frequency.

The method for fusing the contrast images to obtain target contrast images comprises the following steps:

and determining the weighting coefficients of the contrast images corresponding to different imaging modes, and carrying out weighted fusion on the different contrast images based on the weighting coefficients of the contrast images to obtain target contrast images corresponding to different imaging modes.

The imaging mode comprises a penetration mode and/or a resolution mode, wherein the weighting coefficient of the contrast image corresponding to the penetration mode is in negative correlation with the imaging frequency corresponding to the contrast image, and the weighting coefficient of the contrast image corresponding to the resolution mode is in positive correlation with the imaging frequency corresponding to the contrast image.

Wherein the determining the weighting coefficients of the contrast images corresponding to different imaging modes includes:

for any target imaging mode, displaying an adjustment window corresponding to the target contrast image; wherein the adjustment window comprises an adjustment area of each contrast image;

and receiving an adjustment instruction acting on each adjustment area, and adjusting the weighting coefficient of the corresponding contrast image based on the adjustment instruction so as to obtain the weighting coefficient of each contrast image in the target imaging mode.

To achieve the above object, the present application provides an ultrasound contrast imaging apparatus comprising:

The generating module is used for determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe and generating a pulse sequence containing a plurality of ultrasonic signal groups based on the transmitting frequencies; each ultrasonic signal group comprises a plurality of ultrasonic signals, each ultrasonic signal at least comprises two ultrasonic sub-signals with different periodic emission frequencies, the emission frequencies of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and the emission frequencies of the corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different;

the transmitting module is used for sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies;

the processing module is used for processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies and generating corresponding contrast images based on the contrast signals;

and the fusion module is used for fusing the contrast images to obtain target contrast images.

To achieve the above object, the present application provides an ultrasonic apparatus comprising:

A memory for storing a computer program;

a processor for implementing the steps of the ultrasound contrast imaging method as described above when executing the computer program.

To achieve the above object, the present application provides a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of an ultrasound contrast imaging method as described above.

According to the scheme, the ultrasonic contrast imaging method provided by the application comprises the following steps of: determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe, and generating a pulse sequence containing a plurality of ultrasonic signal groups based on the transmitting frequencies; each ultrasonic signal group comprises a plurality of ultrasonic signals, each ultrasonic signal at least comprises two ultrasonic sub-signals with different periodic emission frequencies, the emission frequencies of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and the emission frequencies of the corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different; sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence, and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies; processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies, and generating corresponding contrast images based on the contrast signals; and fusing the contrast images to obtain a target contrast image.

According to the ultrasonic contrast imaging method, the ultrasonic probe can obtain a plurality of contrast signals corresponding to different imaging frequencies by transmitting the complete pulse sequence once, wherein the contrast signals comprise fundamental wave signals and harmonic signals of different imaging frequencies, the fundamental wave signals and the harmonic signals corresponding to the same imaging frequency are mutually enhanced, the enhanced contrast signals can be obtained, and the corresponding contrast image generated based on the enhanced contrast signals can meet the requirements of penetrating power, sensitivity and resolution. The application also discloses an ultrasonic radiography imaging device, ultrasonic equipment and a computer readable storage medium, and the technical effects can be achieved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated in and constitute a part of this specification, illustrate the disclosure and together with the description serve to explain, but do not limit the disclosure. In the drawings:

FIG. 1 is an architecture diagram of an ultrasound imaging system shown in accordance with an exemplary embodiment;

FIG. 2 is an architecture diagram of another ultrasound imaging system shown in accordance with an exemplary embodiment;

FIG. 3 is a flowchart illustrating a method of ultrasound contrast imaging, according to an exemplary embodiment;

FIGS. 4a-4d are schematic diagrams illustrating a first ultrasonic signal, a second ultrasonic signal, a third ultrasonic signal, and a fourth ultrasonic signal, according to an exemplary embodiment;

5a-5d are schematic diagrams illustrating another first, second, third, fourth ultrasonic signal according to an exemplary embodiment;

FIGS. 6a-6d are schematic diagrams illustrating yet another first, second, third, and fourth ultrasonic signal according to an exemplary embodiment;

7a-7f are schematic diagrams illustrating one first, second, third, fourth, fifth, and sixth ultrasonic signal according to an exemplary embodiment;

FIG. 8 is a schematic representation of a display of an ultrasound contrast image, according to an exemplary embodiment;

FIG. 9 is a schematic diagram illustrating an adjustment box of a target contrast image, according to an exemplary embodiment;

FIG. 10 is a block diagram of an ultrasound contrast imaging device according to an exemplary embodiment;

fig. 11 is a block diagram of an ultrasonic device according to an exemplary embodiment.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application. In addition, in the embodiments of the present application, "first," "second," and the like are used to distinguish similar objects, and are not necessarily used to describe a particular order or sequence.

The method and the device can be applied to an ultrasonic imaging system shown in fig. 1, and comprise an ultrasonic host machine, an ultrasonic probe and an upper computer. The upper computer determines a plurality of transmitting frequencies in the effective bandwidth range of the ultrasonic probe, and generates a pulse sequence, namely a transmitting waveform, comprising a plurality of ultrasonic signal groups through scanning time sequence control, wherein each ultrasonic signal group comprises a plurality of ultrasonic signals. Then, the transmission beam is synthesized, the ultrasonic probe is transmitted to the ultrasonic probe, the ultrasonic probe is used for transmitting the ultrasonic probe to the tissue to be inspected, and the contrast agent microbubbles in the tissue generate echo signals. And carrying out beam synthesis on echo signals of each ultrasonic signal, storing the echo signals in a Linebuffer, and carrying out weighted summation or difference processing on echo signals of different ultrasonic signals in the Linebuffer to obtain contrast signals corresponding to different ultrasonic signal groups. The Linebuffer may be a Block RAM (random access memory ) resource inside the FPGA (field programmable gate array ), or an external memory, for example, a DDR (Double Data Rate) or a hard disk, which is not particularly limited herein. Further, the demodulation circuit (such as N-path demodulation circuit in fig. 1, where N is a natural number greater than 0) demodulates the contrast signals corresponding to the ultrasonic signal group to obtain contrast signals corresponding to different imaging frequencies, and sends the contrast signals after signal processing to the upper computer so as to facilitate the imaging processing of the upper computer, specifically, the weighted fusion is performed on different contrast images based on the weighting coefficients of the contrast images corresponding to different imaging modes, so as to obtain target contrast images corresponding to different imaging modes, and then the target contrast images are displayed on the display device.

It can be seen that in fig. 1, the weighting, demodulation and signal processing processes for the echo signals of the different ultrasound signals are performed at the front end of the ultrasound device. Of course, the method can also be performed at the rear end of the upper computer, and the specific structure diagram is shown in fig. 2.

The embodiment of the application discloses an ultrasonic contrast imaging method, which can simultaneously meet the requirements of penetration force, sensitivity and resolution through one-time contrast imaging.

Referring to fig. 3, a flowchart of an ultrasound contrast imaging method is shown according to an exemplary embodiment, as shown in fig. 3, comprising:

s101: determining a plurality of transmitting frequencies within the effective bandwidth range of the ultrasonic probe, and generating a pulse sequence containing a plurality of ultrasonic signal groups based on the transmitting frequencies; each ultrasonic signal group comprises a plurality of ultrasonic signals, each ultrasonic signal at least comprises ultrasonic sub-signals with different emission frequencies in two periods, the emission frequencies of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and the emission frequencies of the corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different;

in a specific implementation, a plurality of transmitting frequencies are determined within an effective bandwidth range of the ultrasonic probe, wherein the effective bandwidth range refers to a frequency range capable of being transmitted by the ultrasonic probe, and it is required to be explained that the plurality of transmitting frequencies cover the effective bandwidth range of the ultrasonic probe as much as possible, that is, the minimum transmitting frequency is close to the minimum effective bandwidth of the ultrasonic probe, that is, the minimum frequency capable of being transmitted by the ultrasonic probe, and the maximum transmitting frequency is close to the maximum effective bandwidth of the ultrasonic probe, that is, the maximum frequency capable of being transmitted by the ultrasonic probe.

Further, a pulse sequence of ultrasonic signals transmitted by the ultrasonic probe is generated based on the determined multiple transmitting frequencies, and the pulse sequence includes multiple ultrasonic signal groups, each ultrasonic signal includes at least two ultrasonic sub-signals with different period transmitting frequencies, voltage amplitudes of different ultrasonic sub-signals in each ultrasonic signal can be the same or different (when not specifically described, the embodiment of the application uses the same voltage amplitude as an example for description), transmitting frequencies of corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and transmitting frequencies of corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different. Alternatively, the two periods may include a first period and a second period, and further, the ultrasonic signal includes an ultrasonic sub-signal of the first period and an ultrasonic sub-signal of the second period, where the transmission frequencies of the ultrasonic sub-signal of the first period and the ultrasonic sub-signal of the second period are different.

As a preferred embodiment, this step may include: determining a reference transmission frequency and a target coefficient, determining the product of the reference transmission frequency and the target coefficient as a first transmission frequency, determining two times of the first transmission frequency as a second transmission frequency, determining three times of the first transmission frequency as a third transmission frequency, and determining four times of the first transmission frequency as a fourth transmission frequency; wherein the first transmitting frequency, the second transmitting frequency, the third transmitting frequency and the fourth transmitting frequency are all within the effective bandwidth range of the ultrasonic probe; generating a pulse sequence comprising a first set of ultrasonic signals and a second set of ultrasonic signals; wherein the first set of ultrasonic signals is generated based on the first and second transmission frequencies and the second set of ultrasonic signals is generated based on the third and fourth transmission frequencies. Optionally, an input instruction of the target coefficient may be received, a value corresponding to the target coefficient is determined based on a value carried by the input instruction, and the target coefficient may be a value between 0 and 1.

It will be appreciated that, for a general ultrasound probe, four transmitting frequencies may cover the effective bandwidth range of the ultrasound probe, preferably, if the reference transmitting Frequency is f and the target coefficient may be 0.5, the first transmitting Frequency is 0.5f, the second transmitting Frequency is f, the third transmitting Frequency is 1.5f, the fourth transmitting Frequency is 2f, if the voltage amplitude of the first ultrasound signal in the first ultrasound signal group is V1, the phase is-i.e., negative phase, the voltage amplitude of the second ultrasound signal is V2, the phase is-i.e., positive phase, the voltage amplitude of the third ultrasound signal in the second ultrasound signal group is V3, the phase is-i.e., the voltage amplitude of the fourth ultrasound signal is V4, the phase is-positive, the first ultrasound signal in the first ultrasound signal group is as shown in fig. 4a (Frequency is shown in the abscissa, the voltage is shown in the ordinate), the second ultrasound signal in the first ultrasound signal group is shown in fig. 4b, the third ultrasound signal group is shown in the fourth ultrasound signal group is shown in the fig. 4 d. For example, for an ultrasonic probe with a center frequency of 3.375MHz and an effective bandwidth of 120%, the effective bandwidth ranges from 1.35MHz to 5.4MHz, so the reference transmit frequency f can be chosen to be 2.7MHz, and the target coefficient is 0.5, four transmit frequencies: 1.35MHz, 2.7Mhz, 4.05MHz and 5.4MHz, namely corresponding to 0.5f, 1.5f and 2f respectively, can cover the effective bandwidth range of the ultrasonic probe.

In addition, if the effective bandwidth range of the ultrasonic probe is narrower, the effective bandwidth range of the ultrasonic probe can be covered by selecting a smaller number of transmitting frequencies under the condition that the reference transmitting frequency and the target coefficient are determined. For example, for an ultrasonic probe with a center frequency of 3.0MHz and an effective bandwidth of 70%, the effective bandwidth range is 1.95MHz-4.05MHz, the reference transmission frequency f is 2.0MHz, the target coefficient is 0.5, 0.5f=1.0 MHz, f=2.0 MHz, 1.5f=3.0 MHz,2 f=4.0 MHz, and it is seen that 0.5f exceeds the effective bandwidth range of the ultrasonic probe, and three transmission frequencies f, 1.5f, and 2f are selected to cover the effective bandwidth range of the ultrasonic probe, so that the transmission frequencies of ultrasonic signals including two periods in the first ultrasonic signal and the second ultrasonic signal are f and f', respectively, and the first ultrasonic signal, the second ultrasonic signal, the third ultrasonic signal, and the fourth ultrasonic signal are shown in fig. 5a-5d, respectively. In addition, f ' may be equal or unequal within the effective bandwidth range of the ultrasound probe, and f ' may be selected in the vicinity of f or 1.95MHz if f ' +.f is not particularly limited herein.

S102: sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence, and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies;

In this step, the ultrasound probe transmits the pulse sequence generated in the previous step, that is, sequentially transmits different ultrasound signals in different ultrasound signal groups, and receives echo signals generated by the contrast agent microbubbles to the transmitted ultrasound signals, and the imaging frequency in this step is the frequency of the echo signals.

It will be appreciated that the voltage amplitude of the different ultrasound signals in the same set of ultrasound signals received by the contrast agent microbubbles may be different. As a possible implementation, this step may include: determining different voltage amplitudes for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group; determining the same number of transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group; and sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence based on the transmission frequency, the voltage amplitude and the number of the transmission aperture array elements of different ultrasonic sub-signals in different ultrasonic signals. That is, the voltage amplitude of the corresponding period between different ultrasonic signals in the same ultrasonic signal group is different, and the number of the transmitting aperture array elements is the same when different ultrasonic signals in the same ultrasonic signal group are transmitted.

It should be noted that, the number of ultrasonic signals included in each ultrasonic signal group is not limited in this embodiment, and each ultrasonic signal group may include two ultrasonic signals or three ultrasonic signals.

If each ultrasonic signal group includes two ultrasonic signals, that is, each ultrasonic signal group includes a first ultrasonic signal and a second ultrasonic signal, correspondingly, determining different voltage amplitudes for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group includes: determining a first voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and a second voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the second voltage amplitude is a preset multiple of the first voltage amplitude. In a specific implementation, the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is a preset multiple of the voltage amplitude of the ultrasonic sub-signal in the first ultrasonic signal, and the number of the transmitting aperture array elements is the same when the ultrasonic sub-signal in the second ultrasonic signal is transmitted as that of the ultrasonic sub-signal in the first ultrasonic signal, so that the voltage amplitudes of the first ultrasonic signal and the second ultrasonic signal received by the contrast agent microbubbles are different. Alternatively, the preset multiple may be a multiple greater than 1, that is, the second voltage amplitude is greater than the first voltage amplitude, and in addition, the preset multiple may be an integer multiple or a non-integer multiple.

It should be noted that, for convenience of subsequent processing of the echo signal, the second voltage amplitude is preferably twice the first voltage amplitude, that is, the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is twice the voltage amplitude of the ultrasonic sub-signal in the first ultrasonic signal.

The pulse sequence comprises two ultrasonic signal groups, namely a first ultrasonic signal group and a second ultrasonic signal group, wherein the first ultrasonic signal group comprises a first ultrasonic signal and a second ultrasonic signal, the second ultrasonic signal group comprises a third ultrasonic signal and a fourth ultrasonic signal, and each ultrasonic signal comprises two periodic ultrasonic sub-signals. The voltage amplitude of the first ultrasonic signal is V1, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the second ultrasonic signal is V2, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the third ultrasonic signal is V3, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, the voltage amplitude of the fourth ultrasonic signal is V4, the ultrasonic sub-signal of the first period is f3, and the ultrasonic sub-signal of the second period is f4. When v1+.v2, v3+.v4, the number of transmit aperture elements is the same for each ultrasound signal, preferably v2=2×v1, v4=2×v3.

It should be noted that, in this embodiment, the phase relation of different ultrasonic signals in the same ultrasonic signal group is not limited, and may be in the same direction or in opposite directions, that is, the phases of the first ultrasonic signal and the second ultrasonic signal in the first ultrasonic signal group may be in the same direction or in opposite directions, and the phases of the third ultrasonic signal and the fourth ultrasonic signal in the second ultrasonic signal group may be in the same direction or in opposite directions. For example, the first ultrasonic signal is shown in fig. 6a, the second ultrasonic signal is shown in fig. 6b, the phases of the first ultrasonic signal and the second ultrasonic signal are reversed, the third ultrasonic signal is shown in fig. 6c, the fourth ultrasonic signal is shown in fig. 6d, and the phases of the third ultrasonic signal and the fourth ultrasonic signal are reversed.

If each ultrasonic signal group includes three ultrasonic signals, that is, each ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, correspondingly, determining different voltage amplitudes for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group includes: determining a third voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and the third ultrasonic signal, and determining a fourth voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the fourth voltage amplitude is a preset multiple of the third voltage amplitude. In a specific implementation, the voltage amplitudes of the ultrasonic sub-signals in the first ultrasonic signal and the third ultrasonic signal are the same, the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is a preset multiple of the voltage amplitudes of the ultrasonic sub-signals in the first ultrasonic signal and the third ultrasonic signal, the number of transmitting aperture array elements is the same when the ultrasonic sub-signals in the first ultrasonic signal, the second ultrasonic signal and the third ultrasonic signal are transmitted, and the voltage amplitudes of the first ultrasonic signal and the second ultrasonic signal received by the contrast agent microbubbles are different. Optionally, the preset multiple may be a multiple greater than 1, that is, the fourth voltage amplitude is greater than the third voltage amplitude, and the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is greater than the voltage amplitudes of the ultrasonic sub-signals in the first ultrasonic signal and the third ultrasonic signal, and in addition, the preset multiple may be an integer multiple or a non-integer multiple.

It should be noted that, in order to facilitate the subsequent processing of the echo signal, it is preferable that the fourth voltage amplitude is twice the third voltage amplitude, that is, the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is twice the voltage amplitude of the ultrasonic sub-signal in the first ultrasonic signal and the third ultrasonic signal, and the voltage amplitude of the ultrasonic sub-signal in the second ultrasonic signal is the sum of the voltage amplitudes of the ultrasonic sub-signals in the first ultrasonic signal and the third ultrasonic signal.

The pulse sequence includes two ultrasonic signal groups, a first ultrasonic signal group and a second ultrasonic signal group, the first ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, the second ultrasonic signal group includes a fourth ultrasonic signal, a fifth ultrasonic signal and a sixth ultrasonic signal, and each ultrasonic signal includes two periodic ultrasonic sub-signals. The voltage amplitude of the first ultrasonic signal is V1, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the second ultrasonic signal is V2, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the third ultrasonic signal is V3, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the fourth ultrasonic signal is V4, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, the voltage amplitude of the fifth ultrasonic signal is V5, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, and the voltage amplitude of the sixth ultrasonic signal is V6, wherein the ultrasonic sub-signal of the first period is f3, and the ultrasonic sub-signal of the second period is f4. When v1+.v2+.v3, v4+.v5+.v6, the number of transmit aperture elements is the same when transmitting each ultrasound signal, preferably v2=2×v1=2×v3, v5=2×v4=2×v6.

The phases of the first ultrasonic signal and the third ultrasonic signal may be the same, the phases of the second ultrasonic signal and the first ultrasonic signal may be different, the phases of the fourth ultrasonic signal and the sixth ultrasonic signal may be the same, the phases of the fifth ultrasonic signal and the fourth ultrasonic signal may be different, and the specific limitation is not performed here. For example, a first ultrasonic signal is shown in fig. 7a, a second ultrasonic signal is shown in fig. 7b, a third ultrasonic signal is shown in fig. 7c, a fourth ultrasonic signal is shown in fig. 7d, a fifth ultrasonic signal is shown in fig. 7e, and a sixth ultrasonic signal is shown in fig. 7 f.

As another possible embodiment, the step may include: determining the same voltage amplitude for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group; determining different numbers of transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group; and sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence based on the transmission frequency, the voltage amplitude and the number of the transmission aperture array elements of different ultrasonic sub-signals in different ultrasonic signals. That is, the voltage amplitude of the corresponding period between different ultrasonic signals in the same ultrasonic signal group is the same, the number of the transmitting aperture array elements is different when different ultrasonic signals in the same ultrasonic signal group are transmitted, and the transmitting energy is adjusted by controlling the number of the transmitting aperture array elements, which is equivalent to adjusting the transmitted voltage amplitude, so that the voltage amplitude of different ultrasonic signals in the same ultrasonic signal group received by the contrast agent microbubbles is different.

If each ultrasonic signal group includes two ultrasonic signals, that is, each ultrasonic signal group includes a first ultrasonic signal and a second ultrasonic signal, correspondingly, determining the number of array elements with different transmitting apertures for the ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group includes: determining the number of first transmitting aperture array elements for ultrasonic sub-signals in the first ultrasonic signal, and determining the number of second transmitting aperture array elements for ultrasonic sub-signals in the second ultrasonic signal; the number of the array elements of the second transmitting aperture is a preset multiple of the number of the array elements of the first transmitting aperture. In a specific implementation, the number of the transmitting aperture array elements of the ultrasonic sub-signals in the second ultrasonic signal is a preset multiple of the number of the transmitting aperture array elements of the ultrasonic sub-signals in the first ultrasonic signal, and the voltage amplitudes of the ultrasonic sub-signals in the first ultrasonic signal and the second ultrasonic signal are the same, so that the voltage amplitudes of the first ultrasonic signal and the second ultrasonic signal received by the contrast agent microbubbles can be different. Optionally, the preset multiple may be a multiple greater than 1, that is, the number of the second transmitting aperture array elements is greater than the number of the first transmitting aperture array elements, and in addition, the preset multiple may be an integer multiple or a non-integer multiple.

It should be noted that, for convenience of subsequent processing of the echo signal, the number of the second transmitting aperture array elements is preferably twice the number of the first transmitting aperture array elements, that is, the number of transmitting aperture array elements of the ultrasonic sub-signal in the second ultrasonic signal is twice the number of transmitting aperture array elements of the ultrasonic sub-signal in the first ultrasonic signal.

The pulse sequence comprises two ultrasonic signal groups, namely a first ultrasonic signal group and a second ultrasonic signal group, wherein the first ultrasonic signal group comprises a first ultrasonic signal and a second ultrasonic signal, the second ultrasonic signal group comprises a third ultrasonic signal and a fourth ultrasonic signal, and each ultrasonic signal comprises two periodic ultrasonic sub-signals. The voltage amplitude of the first ultrasonic signal is V1, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the second ultrasonic signal is V2, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the third ultrasonic signal is V3, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, the voltage amplitude of the fourth ultrasonic signal is V4, the ultrasonic sub-signal of the first period is f3, and the ultrasonic sub-signal of the second period is f4. When v1=v2, v3=v4, the first and third ultrasonic signals may be transmitted using an odd or even aperture, and the second and fourth ultrasonic signals may be transmitted using a full aperture.

If each ultrasonic signal group includes three ultrasonic signals, that is, each ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, correspondingly, determining the number of different transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group includes: determining a transmit aperture of an ultrasound sub-signal in the first ultrasound signal as one of an odd aperture or an even aperture, determining a transmit aperture of an ultrasound sub-signal in the second ultrasound signal as a full aperture, and determining a transmit aperture of an ultrasound sub-signal in the third ultrasound signal as the other of the odd aperture or the even aperture. In a specific implementation, when the voltage amplitudes of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, one of an odd aperture or an even aperture can be adopted to transmit the first ultrasonic signal, a full aperture is adopted to transmit the second ultrasonic signal, and the other of the odd aperture or the even aperture is adopted to transmit the third ultrasonic signal, so that the voltage amplitudes of the first ultrasonic signal and the second ultrasonic signal received by the contrast agent microbubbles can be different. Alternatively, when the emission aperture of the ultrasonic sub-signal in the first ultrasonic signal is an odd aperture, the emission aperture of the ultrasonic sub-signal in the third ultrasonic signal may be an even aperture.

Furthermore, the array elements at the odd positions and the array elements at the even positions can be respectively determined according to the arrangement positions of the array elements. Determining the transmit aperture as an odd aperture may be determining the array elements at odd positions as transmit aperture array elements, i.e. determining the number of array elements at odd positions as the number of transmit aperture array elements; determining the transmit aperture as an even aperture may be determining the array elements at even positions as transmit aperture array elements, i.e. determining the number of array elements at even positions as the number of transmit aperture array elements; determining the transmit aperture as a full aperture may be determining all array elements as transmit aperture array elements, i.e. determining the number of all array elements as transmit aperture array elements.

The pulse sequence includes two ultrasonic signal groups, a first ultrasonic signal group and a second ultrasonic signal group, the first ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, the second ultrasonic signal group includes a fourth ultrasonic signal, a fifth ultrasonic signal and a sixth ultrasonic signal, and each ultrasonic signal includes two periodic ultrasonic sub-signals. The voltage amplitude of the first ultrasonic signal is V1, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the second ultrasonic signal is V2, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the third ultrasonic signal is V3, the ultrasonic sub-signal of the first period is f1, the ultrasonic sub-signal of the second period is f2, the voltage amplitude of the fourth ultrasonic signal is V4, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, the voltage amplitude of the fifth ultrasonic signal is V5, the ultrasonic sub-signal of the first period is f3, the ultrasonic sub-signal of the second period is f4, and the voltage amplitude of the sixth ultrasonic signal is V6, wherein the ultrasonic sub-signal of the first period is f3, and the ultrasonic sub-signal of the second period is f4. When v1=v2=v3, v4=v5=v6, the number of transmit aperture elements is different when transmitting each ultrasonic signal, preferably the second ultrasonic signal is twice the number of transmit aperture elements when transmitting the first ultrasonic signal and the third ultrasonic signal, and the fifth ultrasonic signal is twice the number of transmit aperture elements when transmitting the fourth ultrasonic signal and the sixth ultrasonic signal, i.e. the number of transmit aperture elements of the second ultrasonic signal is the sum of the number of transmit aperture elements of the first ultrasonic signal and the third ultrasonic signal, and the number of transmit aperture elements of the fifth ultrasonic signal is the sum of the number of transmit aperture elements of the fourth ultrasonic signal and the sixth ultrasonic signal. In implementations, the first and fourth ultrasonic signals may be transmitted using one of an odd or even aperture, the second and fifth ultrasonic signals may be transmitted using a full aperture, and the third and sixth ultrasonic signals may be transmitted using the other of the odd or even aperture.

Specifically, the sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence and receiving echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals includes: sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence so that contrast agent microbubbles generate fundamental wave signals corresponding to different first imaging frequencies, generating multiple harmonic signals corresponding to second imaging frequencies based on the fundamental wave signals corresponding to the first imaging frequencies, and generating differential harmonic signals corresponding to third imaging frequencies based on the fundamental wave signals corresponding to the different first imaging frequencies; wherein the second imaging frequency is an integer multiple of the first imaging frequency, and the third imaging frequency is at least one of a difference or a sum between different first imaging frequencies; and receiving fundamental wave signals corresponding to the first imaging frequency, multiple harmonic signals corresponding to the second imaging frequency and differential harmonic signals corresponding to the third imaging frequency. Alternatively, the difference between the different first imaging frequencies may be determined, the sum between the different first imaging frequencies may be determined, and the difference and/or the sum may be determined as the third imaging frequency.

In a specific implementation, the ultrasound probe transmits a pulse sequence, the contrast agent microbubbles generate echo signals, the echo signals may include fundamental wave signals and harmonic signals, the imaging frequency of the fundamental wave signals (i.e., the first imaging frequency) is a transmission frequency, the harmonic signals include differential harmonic signals and multiple harmonic signals, the differential harmonic signals are differential signals of different fundamental wave signals, the imaging frequency of the differential harmonic signals (i.e., the third imaging frequency) is a difference value of different transmission frequencies, and/or the sum value of different transmission frequencies, the multiple harmonic signals may be understood as multiple overlapping of the same fundamental wave signals, such as a second harmonic signal, a third harmonic signal, etc., and the imaging frequency of the multiple harmonic signals (i.e., the second imaging frequency) is an integer multiple of the transmission frequency. Since the harmonic signals of three or more times tend to exceed the effective bandwidth range of the ultrasound probe, they are generally not considered.

As illustrated in fig. 4a to 4d, for the first ultrasonic signal group, the nonlinear fundamental wave signal of 0.5f and the nonlinear fundamental wave signal of f can be directly obtained, and the difference harmonic signal of 0.5f and the difference harmonic signal of 1.5f can be obtained by integrating the nonlinear fundamental wave signal of 0.5f and the nonlinear fundamental wave signal of f. Alternatively, calculating the difference between the nonlinear fundamental wave signal of 0.5f and the nonlinear fundamental wave signal of f may obtain a differential harmonic signal of 0.5f, and calculating the sum of the nonlinear fundamental wave signal of 0.5f and the nonlinear fundamental wave signal of f may obtain a differential harmonic signal of 1.5 f.

The second harmonic signal of 0.5f, namely the harmonic signal of f, can be obtained based on the nonlinear fundamental wave signals of 0.5f corresponding to the first ultrasonic signal and the second ultrasonic signal respectively, and the second harmonic signal of f, namely the harmonic signal of 2f, can be obtained based on the nonlinear fundamental wave signals of f corresponding to the first ultrasonic signal and the second ultrasonic signal respectively. Thus, the contrast signals corresponding to the first ultrasound signal group include a nonlinear fundamental wave signal of 0.5f, a nonlinear fundamental wave signal of f, a differential harmonic signal of 0.5f, a differential harmonic signal of 1.5f, a harmonic signal of f, and a harmonic signal of 2f, and similarly, the contrast signals corresponding to the second ultrasound signal group include a nonlinear fundamental wave signal of 1.5f, a nonlinear fundamental wave signal of 2f, a differential harmonic signal of 0.5f, a differential harmonic signal of 3.5f, a harmonic signal of 3f, and a harmonic signal of 4 f.

S103: processing the echo signals to obtain a plurality of contrast signals corresponding to different imaging frequencies, and generating corresponding contrast images based on the contrast signals;

in this step, echo signals of different ultrasonic signals are processed to obtain a plurality of contrast signals corresponding to different imaging frequencies, where the imaging frequencies may be transmitting frequencies or integer multiples of the transmitting frequencies, the contrast signals include fundamental wave signals and harmonic wave signals of the imaging frequencies, the fundamental wave signals and the harmonic wave signals corresponding to the imaging frequencies are mutually enhanced, an enhanced contrast signal may be obtained, and the enhanced contrast signal is subjected to signal processing to generate a corresponding contrast image and is stored.

As a possible implementation manner, processing the echo signals to obtain a plurality of contrast signals corresponding to different transmission frequencies includes: weighting echo signals of different ultrasonic signals in each ultrasonic signal group based on a voltage amplitude relation and a phase relation among different ultrasonic signals in each ultrasonic signal group to obtain contrast signals corresponding to each ultrasonic signal group; and demodulating the contrast signals corresponding to each ultrasonic signal group by using demodulation circuits corresponding to different imaging frequencies to obtain the contrast signals corresponding to different imaging frequencies.

In a specific implementation, the weighting coefficients of the corresponding echo signals are determined based on the voltage amplitude relationship between the different ultrasound signals in each of the ultrasound signal groups. For the example of fig. 6 a-6 d, if v2=weight_path1×v1, the Weight corresponding to the first ultrasonic signal is weight_path1, the Weight corresponding to the second ultrasonic signal is 1, if v4=weight_path2×v3, the Weight corresponding to the third ultrasonic signal is weight_path2, and the Weight corresponding to the fourth ultrasonic signal is 1. For the example of fig. 7 a-7 f, if v1=v3=v2/weight_path1, the first ultrasonic signal and the third ultrasonic signal have a Weight of 1, the second ultrasonic signal has a Weight of 2/weight_path1, if v4=v6=v5/weight_path2, the fourth ultrasonic signal and the sixth ultrasonic signal have a Weight of 1, and the fifth ultrasonic signal has a Weight of 2/weight_path2.

In a specific implementation, if the voltage amplitudes of different ultrasonic sub-signals in the ultrasonic signals are different, weights may be set for the different ultrasonic sub-signals in the ultrasonic signals according to the proportional relationship of the voltage amplitudes, and the weights of the ultrasonic signals determined in the foregoing embodiment are overlapped and weighted to obtain contrast signals corresponding to the corresponding ultrasonic signal groups.

Further, determining the operation relation of the corresponding echo signals based on the phase relation between different ultrasonic signals in each ultrasonic signal group; if the phase relationships are opposite, the operation relationships are addition, and if the phase relationships are the same, the operation relationships are subtraction. That is, if the phase relationships between the different ultrasonic signals in the ultrasonic signal group are opposite, performing weighted addition processing on the echo signals corresponding to the different ultrasonic signals in the ultrasonic signal group when performing weighted processing; if the phase relation between different ultrasonic signals in the ultrasonic signal group is the same, weighting and subtracting the echo signals corresponding to the different ultrasonic signals in the ultrasonic signal group when weighting is performed.

And weighting echo signals of different ultrasonic signals in each ultrasonic signal group according to the determined weight and the operation relation to obtain contrast signals corresponding to each ultrasonic signal group. For the example of fig. 6 a-6 d, i.e. the phases between the first ultrasound signal and the second ultrasound signal in the first ultrasound signal group are opposite, the first ultrasound signal and the second ultrasound signal are weighted and added when the corresponding contrast signal of the first ultrasound signal group is calculated; and if the phases of the first ultrasonic signal and the second ultrasonic signal in the second ultrasonic signal group are opposite, performing weighted addition processing on the first ultrasonic signal and the second ultrasonic signal when the contrast signal corresponding to the second ultrasonic signal group is calculated. The contrast signal Dataout1 corresponding to the first ultrasonic signal group and the contrast signal Dataout2 corresponding to the second ultrasonic signal group are respectively:

Dataout1＝Weight_Path1×Data_1stTX+Data_2ndTX；

Dataout2＝Weight_Path2×Data_3rdTX+Data_4thTX；

Wherein, data_1sttx is the echo signal of the first ultrasonic signal, data_2ndtx is the echo signal of the second ultrasonic signal, data_3rdtx is the echo signal of the third ultrasonic signal, and data_4thtx is the echo signal of the fourth ultrasonic signal.

In addition, if the phases between the first ultrasonic signal and the second ultrasonic signal in the first ultrasonic signal group are the same, when the contrast signal corresponding to the first ultrasonic signal group is calculated, the first ultrasonic signal and the second ultrasonic signal are subjected to weighted subtraction processing; if the phases of the first ultrasonic signal and the second ultrasonic signal in the second ultrasonic signal group are the same, when the contrast signal corresponding to the second ultrasonic signal group is calculated, the first ultrasonic signal and the second ultrasonic signal are subjected to weighted subtraction processing. Then:

Dataout1＝Weight_Path1×Data_1stTX﹣Data_2ndTX；

Dataout2＝Weight_Path2×Data_3rdTX﹣Data_4thTX。

if the phases of the first ultrasonic signals and the second ultrasonic signals in the first ultrasonic signal group are opposite, weighting and adding the first ultrasonic signals and the second ultrasonic signals when the contrast signals corresponding to the first ultrasonic signal group are calculated; if the phases of the first ultrasonic signal and the second ultrasonic signal in the second ultrasonic signal group are the same, when the contrast signal corresponding to the second ultrasonic signal group is calculated, the first ultrasonic signal and the second ultrasonic signal are subjected to weighted subtraction processing. Then:

Dataout1＝Weight_Path1×Data_1stTX+Data_2ndTX；

Dataout2＝Weight_Path2×Data_3rdTX﹣Data_4thTX。

If the phases of the first ultrasonic signals and the second ultrasonic signals in the first ultrasonic signal group are the same, when the contrast signals corresponding to the first ultrasonic signal group are calculated, the first ultrasonic signals and the second ultrasonic signals are subjected to weighted subtraction processing; if the phases of the first ultrasonic signal and the second ultrasonic signal in the second ultrasonic signal group are opposite, the first ultrasonic signal and the second ultrasonic signal are weighted and added when the contrast signal corresponding to the first ultrasonic signal group is calculated. Then:

Dataout1＝Weight_Path1×Data_1stTX﹣Data_2ndTX；

Dataout2＝Weight_Path2×Data_3rdTX+Data_4thTX。

if the phases of the first ultrasonic signal and the third ultrasonic signal are the same or different from the second ultrasonic signal, the first ultrasonic signal and the third ultrasonic signal may be summed (may be weighted and summed) and then weighted with the second ultrasonic signal, specifically, when the first ultrasonic signal is the same as the second ultrasonic signal, the first ultrasonic signal and the third ultrasonic signal are weighted and subtracted from the second ultrasonic signal, and when the second ultrasonic signal is opposite to the first ultrasonic signal, the second ultrasonic signal is weighted and added.

For the example of fig. 7 a-7 f, the phases between the first ultrasonic signal and the third ultrasonic signal in the first ultrasonic signal group are the same, but opposite to the phases between the second ultrasonic signal, when calculating the contrast signal corresponding to the first ultrasonic signal group, the first ultrasonic signal and the second ultrasonic signal are added together and then are weighted and added with the third ultrasonic signal; and when the contrast signals corresponding to the second ultrasonic signal group are calculated, the fourth ultrasonic signal and the fifth ultrasonic signal are summed and then are subjected to weighted addition processing with the sixth ultrasonic signal. The contrast signal Dataout1 corresponding to the first ultrasonic signal group and the contrast signal Dataout2 corresponding to the second ultrasonic signal group are respectively:

Dataout1＝Data_1stTX+2/Weight_Path1×Data_2ndTX+Data_3rdTX；

Dataout2＝Data_4thTX+2/Weight_Path2×Data_5thTX+Data_6thTX；

Wherein, data_1sttx is the echo signal of the first ultrasonic signal, data_2ndtx is the echo signal of the second ultrasonic signal, data_3rdtx is the echo signal of the third ultrasonic signal, data_4thtx is the echo signal of the fourth ultrasonic signal, data_5thtx is the echo signal of the fifth ultrasonic signal, and data_6thtx is the echo signal of the sixth ultrasonic signal.

In addition, if the phases among the first ultrasonic signal, the second ultrasonic signal and the third ultrasonic signal in the first ultrasonic signal group are the same, when the contrast signal corresponding to the first ultrasonic signal group is calculated, the first ultrasonic signal and the second ultrasonic signal are summed and then are subjected to weighted subtraction processing with the third ultrasonic signal; if the phases of the fourth ultrasonic signal and the sixth ultrasonic signal in the second ultrasonic signal group are the same, but the phases of the fourth ultrasonic signal and the sixth ultrasonic signal are opposite to the phases of the fifth ultrasonic signal, when the contrast signal corresponding to the second ultrasonic signal group is calculated, the fourth ultrasonic signal and the fifth ultrasonic signal are added, and then the fourth ultrasonic signal and the sixth ultrasonic signal are subjected to weighted addition treatment. The contrast signal Dataout1 corresponding to the first ultrasonic signal group and the contrast signal Dataout2 corresponding to the second ultrasonic signal group are respectively:

Dataout1＝Data_1stTX-2/Weight_Path1×Data_2ndTX+Data_3rdTX；

Dataout2＝Data_4thTX+2/Weight_Path2×Data_5thTX+Data_6thTX。

furthermore, the demodulation circuits corresponding to different imaging frequencies are required to respectively demodulate the contrast signals corresponding to each ultrasonic signal group to obtain the contrast signals corresponding to different imaging frequencies. For illustration in fig. 4a-4d, the contrast signals corresponding to the first ultrasound signal group are demodulated by demodulation circuits corresponding to 0.5f, 1.5f, and 2f, respectively, to obtain a first contrast signal of 0.5f (including a nonlinear fundamental signal of 0.5f and a differential harmonic signal of 0.5 f), a second contrast signal of f (including a nonlinear fundamental signal of f and a harmonic signal of f), a third contrast signal of 1.5f (including a differential harmonic signal of 1.5f and a third harmonic of 1.5 f), and a fourth contrast signal of 2f (including a harmonic signal of 2 f). Further, since 3f, 3.5f, and 4f exceed the effective bandwidth range of the ultrasound probe, the demodulation circuits corresponding to 0.5f, 1.5f, and 2f are used to demodulate the contrast signals corresponding to the second ultrasound signal group, respectively, so as to obtain a fifth contrast signal (including a differential harmonic signal of 0.5 f), a sixth contrast signal (including a nonlinear fundamental signal of 1.5 f), and a seventh contrast signal (including a nonlinear fundamental signal of 2 f) of 0.5 f. As can be seen, the 4-channel demodulation circuit is used to demodulate the contrast signals and perform subsequent signal processing, so as to generate seven contrast images corresponding to the seven contrast signals, as shown in table 1:

TABLE 1

5 a-5 d, if f=f', the contrast signals corresponding to the first ultrasound signal group include a nonlinear fundamental wave signal of f and a harmonic wave signal of 2f, and the contrast signals corresponding to the second ultrasound signal group include a nonlinear fundamental wave signal of 1.5f, a nonlinear fundamental wave signal of 2f, a delta harmonic wave signal of 0.5f, a delta harmonic wave signal of 3.5f, a harmonic wave signal of 3f, and a harmonic wave signal of 4 f. Since 3f, 3.5f, 4f exceed the effective bandwidth range of the ultrasound probe, the demodulation circuits corresponding to f and 2f are used for demodulating the contrast signals corresponding to the first ultrasound signal group respectively, so as to obtain a first contrast signal (including a nonlinear fundamental wave signal of f) of f and a second contrast signal (including a harmonic wave signal of 2 f) of f respectively, and the demodulation circuits corresponding to 0.5f, 1.5f and 2f are used for demodulating the contrast signals corresponding to the second ultrasound signal group respectively, so as to obtain a third contrast signal (including a differential harmonic wave signal of 0.5 f) of 0.5f, a fourth contrast signal (including a nonlinear fundamental wave signal of 1.5 f) of 1.5f and a fifth contrast signal (including a nonlinear fundamental wave signal of 2 f) of 2f respectively. As can be seen, the 4-channel demodulation circuit is used to demodulate the contrast signal and perform subsequent signal processing, so as to generate five contrast images corresponding to the five contrast signals, as shown in table 2:

TABLE 2

If f ' is slightly greater than f, the contrast signals corresponding to the first ultrasonic signal group include nonlinear fundamental wave signals of f, nonlinear fundamental waves of f ', differential harmonic signals of f ' -f, differential harmonic signals of f ' +f, harmonic signals of 2f ', and the contrast signals corresponding to the second ultrasonic signal group include nonlinear fundamental wave signals of 1.5f, nonlinear fundamental wave signals of 2f, differential harmonic signals of 0.5f, differential harmonic signals of 3.5f, harmonic signals of 3f, and harmonic signals of 4 f. Since f '-f, 3f, 3.5f, 4f exceed the effective bandwidth range of the ultrasound probe, and f' +f is close to 2f, the demodulation circuits corresponding to f, 2f, f ', 2f' are used to demodulate the contrast signals corresponding to the first ultrasound signal group, respectively, to obtain the first contrast signal of f (including the nonlinear fundamental wave signal of f), the second contrast signal of 2f (including the harmonic wave signal of 2 f), the third contrast signal of f '(including the nonlinear fundamental wave signal of f'), and the fourth contrast signal of 2f '(including the harmonic wave signal of 2 f'), and the demodulation circuits corresponding to 0.5f, 1.5f, 2f are used to demodulate the contrast signals corresponding to the second ultrasound signal group, respectively, to obtain the fifth contrast signal of 0.5f (including the harmonic wave signal of 0.5 f), the sixth contrast signal of 1.5f (including the nonlinear fundamental wave signal of 1.5 f), and the seventh contrast signal of 2f (including the nonlinear fundamental wave signal of 2 f). As can be seen, the 6-channel demodulation circuit is used to demodulate the contrast signals and perform subsequent signal processing, so as to generate seven contrast images corresponding to the seven contrast signals, as shown in table 3:

TABLE 3 Table 3

S104: and fusing the contrast images to obtain a target contrast image.

In this step, different contrast images are fused to obtain a target contrast image. As a possible implementation, this step may include: and determining the weighting coefficients of the contrast images corresponding to different imaging modes, and carrying out weighted fusion on the different contrast images based on the weighting coefficients of the contrast images to obtain target contrast images corresponding to different imaging modes. In specific implementation, weighting and fusing are carried out on each contrast image based on the weighting coefficient of each contrast image, so as to obtain an output target contrast image, wherein the fusion formula is as follows:

wherein sub_imagei is the ith contrast image, coefi is the weighting factor of the ith contrast image, and contextimage is the target contrast image.

The weighting coefficients of the contrast images corresponding to the different imaging modes are different, and the weighting coefficients e [0,1]. The different imaging modes can be obtained by weighting and fusing the different imaging images based on the weighting coefficients of the contrast images corresponding to the different imaging modes, and the imaging modes can comprise a general mode, a penetration mode, a resolution mode and the like, and simultaneously meet the requirements of penetration force, sensitivity and resolution.

For the general mode, the second contrast image and the sixth contrast image may be fused, that is, the second contrast image, the fourth contrast image and the seventh contrast image may be fused, that is, the f and the 2f contrast images may be fused, and the second contrast image, the fourth contrast image, the sixth contrast image and the seventh contrast image may be fused, that is, the f, the 1.5f and the 2f contrast images may be fused, taking table 1 as an example. Of course, other fusion modes exist, and the embodiment is not particularly limited.

For the penetration mode, the penetration force and sensitivity of the contrast image are required to be high, so that the contrast image with low frequency components can be used for fusion, that is, the weighting coefficient of the contrast image corresponding to the penetration mode is inversely related to the imaging frequency corresponding to the contrast image. Taking table 1 as an example, the first contrast image may be used alone as the target contrast image, that is, the 0.5f contrast image alone, the second contrast image may be used alone as the target contrast image, that is, the f contrast image alone, and the first contrast image and the second contrast image may be fused, that is, the 0.5f and f contrast images may be fused. Of course, other fusion modes exist, and the embodiment is not particularly limited.

For the resolution mode, the resolution requirement of the contrast image is high, so that the fusion can be performed by adopting the contrast image with high frequency components, namely the weighting coefficient of the contrast image corresponding to the resolution mode is positively correlated with the imaging frequency corresponding to the contrast image. Taking table 1 as an example, the fourth contrast image, the sixth contrast image and the seventh contrast image may be used for fusion, that is, the contrast images of 1.5f and 2f may be used for fusion, or the fourth contrast image and the seventh contrast image may be used for fusion, that is, the contrast image of 2f may be used for fusion. Of course, other fusion modes exist, and the embodiment is not particularly limited.

It will be appreciated that the user may select one or more of the imaging modes to display the corresponding target contrast signals, and that an ultrasound contrast image may be displayed as shown schematically in fig. 8, with the ultrasound gray scale image of the tissue, the general mode, the penetration mode, and the target ultrasound image in the resolution mode being displayed simultaneously.

Further, since the contrast images corresponding to the contrast signals are generated and stored, the embodiment may further support the user to manually adjust the weighting coefficients of the contrast images, as a possible implementation manner, where determining the weighting coefficients of the contrast images corresponding to different imaging modes includes: for any target imaging mode, displaying an adjustment window corresponding to the target contrast image; wherein the adjustment window comprises an adjustment area of each contrast image; and receiving an adjustment instruction acting on each adjustment area, and adjusting the weighting coefficient of the corresponding contrast image based on the adjustment instruction so as to obtain the weighting coefficient of each contrast image in the target imaging mode. In a specific implementation, a user may click on a certain displayed target contrast image, and further display an adjustment window (as shown in fig. 9) of the target contrast image, and the user may adjust a corresponding weighting coefficient by dragging a black point corresponding to each contrast image up and down in an adjustment area of each contrast image, so as to meet requirements of different scenes. Wherein, an adjusting rod (vertical line) and a black point on the adjusting rod form an adjusting control of a contrast image. According to the embodiment, the personalized setting of the weighting coefficients is realized through the adjustment of the adjustment control, the personalized adjustment of the image fusion can be realized, and the requirements of different scenes are met.

Alternatively, the ultrasonic device may include a display screen for outputting and displaying an ultrasonic image or the like, and a touch screen for receiving an input signal such as: key information entered by a user on a virtual keyboard. The adjustment windows can be displayed in the display screen and the touch screen, and black points corresponding to the contrast images can be slid in a touch manner so as to adjust the weight of the corresponding contrast images. For the ultrasonic equipment without a touch screen, an adjusting window can be displayed in the display screen in a popup window mode, and at the moment, black points of corresponding contrast images in the adjusting window can be slid through a knob or a deflector rod arranged on the ultrasonic equipment, so that the weight of the corresponding contrast images is adjusted.

Optionally, different areas in a display screen of the ultrasonic device can be respectively used as display windows of contrast images in different imaging modes, when a certain display window is selected, it is determined that a corresponding target imaging mode is selected, an adjustment window of a target contrast image corresponding to the target imaging mode is displayed, for the ultrasonic device with a touch screen, the adjustment window can be directly displayed on the touch screen, and for the ultrasonic device without the touch screen, the adjustment window can be sprung out from a display main interface of the contrast image. And determining the weighting coefficient of each contrast image based on the adjustment instruction acting on the adjustment window, and further carrying out weighted fusion processing to obtain the target caused image.

According to the ultrasonic contrast imaging method provided by the embodiment of the application, the ultrasonic probe can obtain a plurality of contrast signals corresponding to different imaging frequencies by transmitting the complete pulse sequence once, wherein the contrast signals comprise fundamental wave signals and harmonic signals of different imaging frequencies, the fundamental wave signals and the harmonic signals corresponding to the same imaging frequency are mutually enhanced, the enhanced contrast signals can be obtained, and the corresponding contrast image generated based on the enhanced contrast signals can meet the requirements of penetrating power, sensitivity and resolution.

An ultrasound imaging apparatus according to an embodiment of the present application is described below, and an ultrasound imaging apparatus described below and an ultrasound imaging method described above may be referred to with reference to each other.

Referring to fig. 10, a structural diagram of an ultrasound contrast imaging apparatus according to an exemplary embodiment is shown, as shown in fig. 10, including:

a generating module 100, configured to determine a plurality of transmission frequencies within an effective bandwidth range of the ultrasound probe, and generate a pulse sequence including a plurality of ultrasound signal groups based on the plurality of transmission frequencies; each ultrasonic signal group comprises a plurality of ultrasonic signals, each ultrasonic signal at least comprises two ultrasonic sub-signals with different periodic emission frequencies, the emission frequencies of the corresponding periods between different ultrasonic signals in the same ultrasonic signal group are the same, and the emission frequencies of the corresponding periods between different ultrasonic signals in different ultrasonic signal groups are different;

The transmitting module 200 is configured to sequentially transmit different ultrasonic signals in different ultrasonic signal groups in the pulse sequence, and receive echo signals generated by contrast agent microbubbles to the transmitted ultrasonic signals; the echo signals comprise fundamental wave signals and harmonic wave signals corresponding to different imaging frequencies;

the processing module 300 is configured to process the echo signal to obtain a plurality of contrast signals corresponding to different imaging frequencies, and generate a corresponding contrast image based on the contrast signals;

and the fusion module 400 is used for fusing the contrast images to obtain target contrast images.

According to the ultrasonic contrast imaging device provided by the embodiment of the application, the ultrasonic probe can obtain a plurality of contrast signals corresponding to different imaging frequencies by transmitting the complete pulse sequence once, wherein the contrast signals comprise fundamental wave signals and harmonic signals of different imaging frequencies, the fundamental wave signals and the harmonic signals corresponding to the same imaging frequency are mutually enhanced, the enhanced contrast signals can be obtained, and the corresponding contrast image generated based on the enhanced contrast signals can meet the requirements of penetrating power, sensitivity and resolution.

On the basis of the above embodiment, as a preferred implementation manner, the generating module 100 is specifically configured to: determining a reference transmission frequency and a target coefficient, determining the product of the reference transmission frequency and the target coefficient as a first transmission frequency, determining two times of the first transmission frequency as a second transmission frequency, determining three times of the first transmission frequency as a third transmission frequency, and determining four times of the first transmission frequency as a fourth transmission frequency; wherein the first transmitting frequency, the second transmitting frequency, the third transmitting frequency and the fourth transmitting frequency are all within the effective bandwidth range of the ultrasonic probe; generating a pulse sequence comprising a first set of ultrasonic signals and a second set of ultrasonic signals; wherein the first set of ultrasonic signals is generated based on the first and second transmission frequencies and the second set of ultrasonic signals is generated based on the third and fourth transmission frequencies.

Based on the above embodiment, as a preferred implementation manner, the transmitting module 200 includes:

the second determining unit is used for determining different voltage amplitudes for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group;

a third determining unit, configured to determine the same number of transmitting aperture array elements for ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group;

the first transmitting unit is used for sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence based on the transmitting frequency, the voltage amplitude and the transmitting aperture of different ultrasonic sub-signals in different ultrasonic signals.

On the basis of the above embodiment, as a preferred implementation manner, each ultrasonic signal group includes a first ultrasonic signal and a second ultrasonic signal, and the second determining unit is specifically configured to: determining a first voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and a second voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the second voltage amplitude is a preset multiple of the first voltage amplitude.

On the basis of the above embodiment, as a preferred implementation, the second voltage amplitude is twice the first voltage amplitude.

On the basis of the above embodiment, as a preferred implementation manner, each ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, and the second determining unit is specifically configured to: determining a third voltage amplitude for an ultrasonic sub-signal in the first ultrasonic signal and the third ultrasonic signal, and determining a fourth voltage amplitude for an ultrasonic sub-signal in the second ultrasonic signal; wherein the fourth voltage amplitude is a preset multiple of the third voltage amplitude.

On the basis of the above embodiment, as a preferred implementation, the fourth voltage amplitude is twice the third voltage amplitude.

a fourth determining unit, configured to determine the same voltage amplitude for ultrasonic sub-signals in corresponding periods in different ultrasonic signals in the same ultrasonic signal group;

a fifth determining unit, configured to determine the number of different transmitting aperture array elements for the ultrasonic sub-signals in different ultrasonic signals in the same ultrasonic signal group;

and the second transmitting unit is used for sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence based on the transmitting frequency, the voltage amplitude and the transmitting aperture of different ultrasonic sub-signals in different ultrasonic signals.

On the basis of the above embodiment, as a preferred implementation manner, each ultrasonic signal group includes a first ultrasonic signal and a second ultrasonic signal, and the fifth determining unit is specifically configured to: determining the number of first transmitting aperture array elements for ultrasonic sub-signals in the first ultrasonic signal, and determining the number of second transmitting aperture array elements for ultrasonic sub-signals in the second ultrasonic signal; the number of the array elements of the second transmitting aperture is a preset multiple of the number of the array elements of the first transmitting aperture.

On the basis of the above embodiment, as a preferred implementation manner, the number of the second transmitting aperture array elements is twice that of the first transmitting aperture array elements.

On the basis of the above embodiment, as a preferred implementation manner, each ultrasonic signal group includes a first ultrasonic signal, a second ultrasonic signal and a third ultrasonic signal, and the fifth determining unit is specifically configured to: determining a transmit aperture of an ultrasound sub-signal in the first ultrasound signal as one of an odd aperture or an even aperture, determining a transmit aperture of an ultrasound sub-signal in the second ultrasound signal as a full aperture, and determining a transmit aperture of an ultrasound sub-signal in the third ultrasound signal as the other of the odd aperture or the even aperture.

Based on the above embodiments, as a preferred implementation, the processing module 300 includes:

the processing unit is used for carrying out weighting processing on echo signals of different ultrasonic signals in each ultrasonic signal group based on a voltage amplitude relation and a phase relation between different ultrasonic signals in each ultrasonic signal group to obtain contrast signals corresponding to each ultrasonic signal group;

the demodulation unit is used for demodulating the contrast signals corresponding to each ultrasonic signal group by utilizing demodulation circuits corresponding to different imaging frequencies to obtain the contrast signals corresponding to different imaging frequencies;

and the generating unit is used for generating a corresponding contrast image based on the contrast signal.

On the basis of the above embodiment, as a preferred implementation manner, the processing unit is specifically configured to: determining a weighting coefficient of the corresponding echo signal based on a voltage amplitude relation between different ultrasonic signals in each ultrasonic signal group; determining the operation relation of the corresponding echo signals based on the phase relation between different ultrasonic signals in each ultrasonic signal group; if the phase relations are opposite, the operation relations are addition, and if the phase relations are the same, the operation relations are subtraction; and carrying out weighting processing based on the weighting coefficients and the operation relations of the echo signals of different ultrasonic signals in each ultrasonic signal group to obtain the contrast signals corresponding to each ultrasonic signal group.

On the basis of the above embodiment, as a preferred implementation manner, the transmitting module 200 is specifically configured to: sequentially transmitting different ultrasonic signals in different ultrasonic signal groups in the pulse sequence so that contrast agent microbubbles generate fundamental wave signals corresponding to different first imaging frequencies, generating multiple harmonic signals corresponding to second imaging frequencies based on the fundamental wave signals corresponding to the first imaging frequencies, and generating differential harmonic signals corresponding to third imaging frequencies based on the fundamental wave signals corresponding to the different first imaging frequencies; wherein the second imaging frequency is an integer multiple of the first imaging frequency, and the third imaging frequency is at least one of a difference or a sum between different first imaging frequencies; and receiving fundamental wave signals corresponding to the first imaging frequency, multiple harmonic signals corresponding to the second imaging frequency and differential harmonic signals corresponding to the third imaging frequency.

Based on the above embodiment, as a preferred implementation manner, the fusion module 400 includes:

a first determining unit, configured to determine weighting coefficients of respective contrast images corresponding to different imaging modes;

and the fusion unit is used for carrying out weighted fusion on different contrast images based on the weighting coefficients of the contrast images to obtain target contrast images corresponding to different imaging modes.

On the basis of the above embodiment, as a preferred implementation manner, the imaging mode includes a penetration mode and/or a resolution mode, wherein a weighting coefficient of a contrast image corresponding to the penetration mode is inversely related to an imaging frequency corresponding to the contrast image, and a weighting coefficient of a contrast image corresponding to the resolution mode is positively related to the imaging frequency corresponding to the contrast image.

On the basis of the foregoing embodiment, as a preferred implementation manner, the first determining unit is specifically configured to display, for any one of target imaging modes, an adjustment window corresponding to the target contrast image; wherein the adjustment window comprises an adjustment area of each contrast image; and receiving an adjustment instruction acting on each adjustment area, and adjusting the weighting coefficient of the corresponding contrast image based on the adjustment instruction so as to obtain the weighting coefficient of each contrast image in the target imaging mode.

The specific manner in which the various modules perform the operations in the apparatus of the above embodiments have been described in detail in connection with the embodiments of the method, and will not be described in detail herein.

Based on the hardware implementation of the program modules, and in order to implement the method of the embodiments of the present application, the embodiments of the present application further provide an ultrasound device, fig. 11 is a block diagram of an ultrasound device according to an exemplary embodiment, and as shown in fig. 11, the ultrasound device includes:

A communication interface 1 capable of information interaction with other devices such as network devices and the like;

and the processor 2 is connected with the communication interface 1 to realize information interaction with other devices and is used for executing the ultrasonic contrast imaging method provided by one or more technical schemes when running the computer program. And the computer program is stored on the memory 3.

Of course, in practice, the various components in the ultrasound device are coupled together by a bus system 4. It will be appreciated that the bus system 4 is used to enable connected communications between these components. The bus system 4 comprises, in addition to a data bus, a power bus, a control bus and a status signal bus. But for clarity of illustration the various buses are labeled as bus system 4 in fig. 11.

The memory 3 in the embodiment of the present application is used to store various types of data to support the operation of the ultrasound apparatus. Examples of such data include: any computer program for operating on an ultrasound device.

It will be appreciated that the memory 3 may be either volatile memory or nonvolatile memory, and may include both volatile and nonvolatile memory. Wherein the nonvolatile Memory may be Read Only Memory (ROM), programmable Read Only Memory (PROM, programmable Read-Only Memory), erasable programmable Read Only Memory (EPROM, erasable Programmable Read-Only Memory), electrically erasable programmable Read Only Memory (EEPROM, electrically Erasable Programmable Read-Only Memory), magnetic random access Memory (FRAM, ferromagnetic random access Memory), flash Memory (Flash Memory), magnetic surface Memory, optical disk, or compact disk Read Only Memory (CD-ROM, compact Disc Read-Only Memory); the magnetic surface memory may be a disk memory or a tape memory. The volatile memory may be random access memory (RAM, random Access Memory), which acts as external cache memory. By way of example, and not limitation, many forms of RAM are available, such as static random access memory (SRAM, static Random Access Memory), synchronous static random access memory (SSRAM, synchronous Static Random Access Memory), dynamic random access memory (DRAM, dynamic Random Access Memory), synchronous dynamic random access memory (SDRAM, synchronous Dynamic Random Access Memory), double data rate synchronous dynamic random access memory (ddr SDRAM, double Data Rate Synchronous Dynamic Random Access Memory), enhanced synchronous dynamic random access memory (ESDRAM, enhanced Synchronous Dynamic Random Access Memory), synchronous link dynamic random access memory (SLDRAM, syncLink Dynamic Random Access Memory), direct memory bus random access memory (DRRAM, direct Rambus Random Access Memory). The memory 3 described in the embodiments of the present application is intended to comprise, without being limited to, these and any other suitable types of memory.

The method disclosed in the embodiments of the present application may be applied to the processor 2 or implemented by the processor 2. The processor 2 may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware in the processor 2 or by instructions in the form of software. The processor 2 described above may be a general purpose processor, DSP, or other programmable logic device, discrete gate or transistor logic device, discrete hardware components, or the like. The processor 2 may implement or perform the methods, steps and logic blocks disclosed in the embodiments of the present application. The general purpose processor may be a microprocessor or any conventional processor or the like. The steps of the method disclosed in the embodiments of the present application may be directly embodied in a hardware decoding processor or implemented by a combination of hardware and software modules in the decoding processor. The software modules may be located in a storage medium in the memory 3 and the processor 2 reads the program in the memory 3 to perform the steps of the method described above in connection with its hardware.

The processor 2 implements corresponding flows in the methods of the embodiments of the present application when executing the program, and for brevity, will not be described in detail herein.

In an exemplary embodiment, the present application also provides a storage medium, i.e. a computer storage medium, in particular a computer readable storage medium, for example comprising a memory 3 storing a computer program executable by the processor 2 for performing the steps of the method described above. The computer readable storage medium may be FRAM, ROM, PROM, EPROM, EEPROM, flash Memory, magnetic surface Memory, optical disk, or CD-ROM.

Those of ordinary skill in the art will appreciate that: all or part of the steps for implementing the above method embodiments may be implemented by hardware associated with program instructions, where the foregoing program may be stored in a computer readable storage medium, and when executed, the program performs steps including the above method embodiments; and the aforementioned storage medium includes: a removable storage device, ROM, RAM, magnetic or optical disk, or other medium capable of storing program code.

Alternatively, the integrated units described above may be stored in a computer readable storage medium if implemented in the form of software functional modules and sold or used as a stand-alone product. Based on such understanding, the technical solutions of the embodiments of the present application may be embodied in essence or a part contributing to the prior art in the form of a software product stored in a storage medium, including several instructions for causing an ultrasound device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a removable storage device, ROM, RAM, magnetic or optical disk, or other medium capable of storing program code.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An ultrasound contrast imaging method, comprising:

and fusing the contrast images to obtain a target contrast image.

2. The ultrasound contrast imaging method of claim 1, wherein the determining a plurality of transmit frequencies within an effective bandwidth of the ultrasound probe, generating a pulse sequence comprising a plurality of ultrasound signal sets based on the plurality of transmit frequencies, comprises:

3. The ultrasound contrast imaging method of claim 1, wherein said sequentially transmitting different ones of the different sets of ultrasound signals in the pulse sequence comprises:

4. A method of ultrasound contrast imaging according to claim 3, wherein each ultrasound signal group comprises a first ultrasound signal and a second ultrasound signal, and wherein said determining different voltage amplitudes for corresponding periods of ultrasound sub-signals in different ultrasound signals in the same ultrasound signal group, respectively, comprises:

5. The ultrasound contrast imaging method of claim 3, wherein each ultrasound signal group includes a first ultrasound signal, a second ultrasound signal, and a third ultrasound signal, and wherein the determining different voltage amplitudes for the ultrasound sub-signals of the corresponding period in the different ultrasound signals in the same ultrasound signal group, respectively, includes:

6. The ultrasound contrast imaging method of claim 1, wherein said sequentially transmitting different ones of the different sets of ultrasound signals in the pulse sequence comprises:

7. The ultrasound contrast imaging method of claim 6, wherein each ultrasound signal group includes a first ultrasound signal and a second ultrasound signal, and wherein the determining a different number of transmit aperture elements for ultrasound sub-signals in different ultrasound signals in the same ultrasound signal group, respectively, includes:

8. The ultrasound contrast imaging method of claim 7, wherein the number of second transmit aperture elements is twice the number of first transmit aperture elements.

9. The ultrasound contrast imaging method of claim 8, wherein each ultrasound signal group includes a first ultrasound signal, a second ultrasound signal, and a third ultrasound signal, and wherein determining the number of different transmit aperture array elements for the ultrasound sub-signals in different ultrasound signals in the same ultrasound signal group, respectively, comprises:

10. The ultrasound contrast imaging method according to any one of claims 1 to 9, wherein processing the echo signals to obtain contrast signals corresponding to a plurality of different imaging frequencies comprises:

11. The ultrasound contrast imaging method of claim 10, wherein the weighting the echo signals of the different ultrasound signals in each of the ultrasound signal groups based on the voltage amplitude relationship and the phase relationship between the different ultrasound signals in each of the ultrasound signal groups to obtain the corresponding contrast signals of each of the ultrasound signal groups comprises:

12. The ultrasound contrast imaging method of any of claims 1 to 9, wherein the sequentially transmitting different ultrasound signals of different sets of ultrasound signals in the pulse sequence and receiving echo signals generated by contrast agent microbubbles for the transmitted ultrasound signals, comprises:

13. The ultrasound contrast imaging method according to any one of claims 1 to 9, wherein fusing the contrast images to obtain a target contrast image comprises:

14. The ultrasound contrast imaging method of claim 13, wherein the imaging modes include a transmission mode and/or a resolution mode, wherein a weighting coefficient of a contrast image corresponding to the transmission mode is inversely related to an imaging frequency corresponding to the contrast image, and wherein a weighting coefficient of a contrast image corresponding to the resolution mode is positively related to the imaging frequency corresponding to the contrast image.

15. The ultrasound contrast imaging method of claim 13, wherein determining the weighting coefficients for each contrast image for the different imaging modes comprises:

16. An ultrasound contrast imaging apparatus, comprising:

17. An ultrasound device, comprising:

a memory for storing a computer program;

a processor for implementing the steps of the ultrasound contrast imaging method as claimed in any one of claims 1 to 15 when executing said computer program.

18. A computer readable storage medium, characterized in that it has stored thereon a computer program which, when executed by a processor, implements the steps of the ultrasound contrast imaging method according to any of claims 1 to 15.