CN114073541A

CN114073541A - Method for ultrasound contrast imaging, ultrasound apparatus and computer storage medium

Info

Publication number: CN114073541A
Application number: CN202010802520.XA
Authority: CN
Inventors: 桑茂栋; 侯龙龙; 王渊; 杨鹏飞
Original assignee: Shenzhen Mindray Bio Medical Electronics Co Ltd; Beijing Shen Mindray Medical Electronics Technology Research Institute Co Ltd
Current assignee: Shenzhen Mindray Bio Medical Electronics Co Ltd; Beijing Shen Mindray Medical Electronics Technology Research Institute Co Ltd
Priority date: 2020-08-11
Filing date: 2020-08-11
Publication date: 2022-02-22

Abstract

A method of ultrasound contrast imaging, an ultrasound apparatus and a computer storage medium are disclosed. The method comprises the following steps: exciting an ultrasonic probe with a target transmitting voltage to transmit ultrasonic beams to a target object which is perfused with a contrast agent, wherein the target transmitting voltage is determined according to the gear adjustment of a user on the sound power, and the corresponding voltage variation between adjacent gears is uneven; determining a front-end analog gain according to gear adjustment; receiving a slave ultrasound echo based on a front-end analog gain; processing the ultrasonic echo to obtain an ultrasonic echo signal; and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal. Therefore, the target transmitting voltage can be adjusted along with the adjustment of the sound power gear by a user, and the transmitting voltage is not uniform along with the change of the gear; furthermore, the front-end analog gain can be adjusted based on the adjustment of the user on the sound power gear, so that the brightness jump of the ultrasonic contrast image caused by the change of the microbubble echo intensity caused by the change of the transmitting voltage is avoided.

Description

Method for ultrasound contrast imaging, ultrasound apparatus and computer storage medium

Technical Field

Embodiments of the present invention relate to the field of ultrasound, and more particularly, to a method for ultrasound contrast imaging, an ultrasound apparatus, and a computer storage medium.

Background

The ultrasonic examination has no radiation, convenient use and low cost, and is one of important imaging tools. In recent years, ultrasound contrast imaging has played an increasingly important role in the diagnosis of benign and malignant lesions, which can be accomplished by injecting an ultrasound contrast agent into the body and imaging using ultrasound contrast imaging techniques.

The main component of the ultrasonic contrast agent is microbubbles of inert gas encapsulated by a special material shell. Microbubbles are very sensitive to changes in excitation sound pressure, and particularly, changes in the peak-to-peak value of the excitation voltage of the contrast device have a more significant effect on microbubbles in the scanned slice near the probe. The existing ultrasonic equipment with the radiography function has multi-stage sound output control, and can meet the high voltage requirement of conventional imaging and the low voltage requirement of the radiography mode. However, when the Acoustic Power (AP) is decreased or increased, the voltage change may cause a corresponding change in the microbubble echo intensity, so that the brightness of the obtained ultrasound contrast image may jump, which may be unfavorable for human observation, and may even cause an inaccurate analysis result based on the ultrasound contrast image.

Disclosure of Invention

The embodiment of the invention provides an ultrasonic contrast imaging method, an ultrasonic device and a computer storage medium.

In a first aspect, there is provided a method of ultrasound contrast imaging, comprising:

exciting an ultrasonic probe with a target transmitting voltage to transmit ultrasonic beams to a target object which is perfused with a contrast agent, wherein the target transmitting voltage is determined according to the gear adjustment of a user on the acoustic power, and the corresponding voltage variation between adjacent gears is not uniform;

determining front-end analog gain according to the gear adjustment of the user on the sound power;

receiving an ultrasonic echo returned from the target object based on the front-end analog gain;

processing the ultrasonic echo to obtain an ultrasonic echo signal;

and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal.

In a second aspect, there is provided a method of ultrasound contrast imaging, comprising:

receiving an ultrasonic echo returned from the target object to obtain an ultrasonic echo signal;

In a third aspect, there is provided an ultrasound apparatus comprising:

an ultrasonic probe;

a transmission/reception selection switch for exciting an ultrasound probe to transmit an ultrasonic beam to a target object perfused with a contrast agent at a target transmission voltage, and exciting the ultrasound probe to receive an ultrasonic echo returned from the target object via a reception circuit, wherein the target transmission voltage is determined according to a user's gear adjustment of acoustic power, and corresponding voltage variation between adjacent gears is non-uniform;

a memory for storing a program executed by the processor;

the processor is used for processing the ultrasonic echo to obtain an ultrasonic echo signal and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal;

a display for displaying the ultrasound contrast image.

In a fourth aspect, there is provided a computer storage medium having stored thereon a computer program which, when executed by a computer or processor, performs the steps of the method of the first or second aspect.

Therefore, in the embodiment of the invention, along with the adjustment of the sound power gear by the user, the adjustment of the transmitting voltage can be realized, and the transmitting voltage is not uniform along with the change of the gear; furthermore, the front-end analog gain can be adjusted based on the adjustment of the user to the sound power gear, so that the brightness jump of the ultrasonic contrast image caused by the change of the microbubble echo intensity caused by the change of the transmitting voltage is avoided.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor.

FIG. 1 is a schematic block diagram of an ultrasound device;

FIG. 2 is a schematic flow chart of an ultrasound contrast imaging method of an embodiment of the present invention;

FIG. 3 is a schematic block diagram of an ultrasound system;

FIG. 4 is another schematic flow chart diagram of an ultrasound contrast imaging method of an embodiment of the present invention;

FIG. 5 is a graphical illustration of a logarithmic curve relationship between the launch voltage and the gear position of an embodiment of the present invention;

FIG. 6 is a schematic diagram of a preset analog gain curve according to an embodiment of the present invention;

FIG. 7 is a schematic diagram of a front-end analog gain curve of an embodiment of the present invention;

fig. 8 is a schematic of an overall gain curve of an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In recent years, ultrasound contrast imaging has played an increasingly important role in the diagnosis of malignant diseases such as liver cancer, thyroid cancer, and breast cancer.

The scattering intensity of the ultrasonic wave is related to the size, shape and acoustic impedance difference of the scatterer and surrounding tissues, and the scattering in blood is enhanced by adding a medium (such as micro-bubbles) with acoustic impedance different from that of the blood, which is the basic principle of acoustic contrast.

By using the principle, the ultrasonic contrast agent (the solution containing the microbubbles) is injected through the vein, and then the contrast agent can enter the organs and tissues along with the blood flow perfusion, so that the organs and the tissues are developed or enhanced on the ultrasonic equipment, thereby providing an important basis for clinical diagnosis.

When a doctor uses an ultrasonic contrast device to perform contrast examination, the doctor generally starts a timer while injecting an ultrasonic contrast agent, and stores a focus image in a scanning section in a backward storage mode. After the examination is finished, the clinician opens the stored radiography film data to carry out retrospective analysis, observes the perfusion mode of the contrast agent microbubble in the focus and compares with the microbubble perfusion mode in the surrounding normal tissues, and determines the property of the focus by combining with the medical history analysis, thereby carrying out differential diagnosis of benign and malignant diseases. In addition, doctors can also quantitatively analyze the stored radiography film data more deeply by means of a radiography quantitative analysis tool to carry out research with statistical significance, expect to find the ultrasonic radiography expression rules of certain diseases and the like.

It is understood that "angiography" refers to a medical imaging technique for visualizing the interior or lumen of blood vessels and organs of the body, which is particularly applicable to arteries, veins and the heart chamber. This has traditionally been done by injecting a radiopaque contrast agent into the vessel and imaging using X-ray based techniques (e.g. fluoroscopy). Angiography is traditionally strictly defined as projection-based radiography. However, recently this term has also been applied to newer vascular imaging techniques, such as CT angiography and MR angiography.

Ultrasound contrast agents rely on different ways in which sound waves reflect from interfaces between substances. This may be a small bubble or a surface of a more complex structure. For example, the contrast agent may be a gas-filled microbubble that is administered intravenously to the systemic circulation. Microbubbles are highly echogenic (the ability of an object to reflect ultrasound). The gas in the microbubbles is very different from the echogenicity around the soft tissues of the body. Thus, ultrasound imaging using microbubble contrast agents enhances ultrasound backscatter of ultrasound waves to produce ultrasound maps with increased contrast due to high echo contrast. Contrast enhanced ultrasound can be used to image blood perfusion in organs, measure blood flow rates in the heart and other organs, and for other applications, among others.

The conventional ultrasonic imaging modes such as B-mode, color Doppler and the like are the most potential of the mining development system and probe, and the imaging signal-to-noise ratio and the penetrating power are pursued as much as possible under the condition of ensuring the safety, so that high transmitting energy/voltage is used. The contrast imaging mode mainly relies on the reflected echo of microbubbles for imaging, and in order to prevent the microbubbles from being broken, the contrast imaging mode needs the system to work at a low voltage. Therefore, the ultrasonic equipment with the radiography function has multi-stage sound output control, and can meet the high voltage requirement of conventional imaging and the low voltage requirement of the radiography mode. For example, IEC60601-2-37 specifies that for systems displaying Mechanical Index (MI) parameters in real time, the step size of MI must not exceed 0.2dB when adjusting the gear of the acoustic power. Two typical problems are encountered if only a multistage acoustic output system meets this specification:

1. the quantization level of the emission voltage (or Acoustic output Power) of the device is not sufficient. For example, if the variation step of MI is assumed to be 0.15 (less than 0.2 meets the regulatory requirement), and contrast imaging is performed under the transmission condition of a certain gear AP of the system, if the phenomenon that the ultrasound contrast agent microbubbles are broken is found, the user chooses to lower the gear AP. A decrease of 0.15 in MI results in insufficient echo signal strength generated by the microbubbles under the transmission condition of the gear, thereby affecting the CTR and the penetration of the contrast image. Although only the first gear AP is lowered, this phenomenon illustrates that the transmitted energy is excessively lowered and the appropriate acoustic output level should lie between these two gears.

2. Changing the acoustic output causes contrast image brightness jumps. When the acoustic output energy is reduced or increased, the voltage change can cause the microbubble echo intensity to generate corresponding change, so that the brightness of the contrast image jumps, and the observation by human eyes is not facilitated. For example, in order to reduce or even avoid the microbubble shattering phenomenon as much as possible, the user may lower the AP range, and the brightness of the contrast image may be correspondingly reduced, thereby affecting the observation of the microbubble perfusion condition in the near-field tissue or the lesion within the imaging range.

An embodiment of the present invention provides a method for ultrasound contrast imaging, which may be implemented by an ultrasound apparatus, which may also be referred to as an ultrasound device or an ultrasound contrast device or system, as shown in fig. 1, the ultrasound apparatus 10 includes an ultrasound probe 110, a transmission/reception selection switch 120, a transmission circuit 160, a reception circuit 170, a memory 130, a processor 140, and a display 150.

The target object may be perfused with a contrast agent through the injector. The transmission/reception selection switch 120 may excite the ultrasound probe 110 at a target transmission voltage to transmit an ultrasonic beam to a target object perfused with a contrast agent via the transmission circuit 160, and receive an ultrasonic echo of the ultrasonic beam returned from the target object by the ultrasound probe 110 via the reception circuit 170. The processor 140 may obtain an ultrasound echo signal based on the ultrasound echoes of the ultrasound beams and obtain an ultrasound contrast image of the target object from the ultrasound echo signal.

Illustratively, the ultrasound contrast images obtained by the processor 140 may be stored in the memory 130. Alternatively, the ultrasound contrast image may be displayed on the display 150.

Alternatively, the display 150 in the ultrasound device 10 may be a touch screen, a liquid crystal display, or the like; or the display 150 may be a separate display device such as a liquid crystal display, a television, or the like, separate from the ultrasound apparatus 10; or the display 150 may be a display screen of an electronic device such as a smart phone, a tablet computer, etc. The number of the display 150 may be one or more.

Alternatively, the memory 130 in the ultrasound device 10 may be volatile memory and/or non-volatile memory, removable memory and/or non-removable memory, etc., such as flash memory cards, solid state memory, hard disk, etc.

Alternatively, the processor 140 in the ultrasound device 10 may be implemented by software, hardware, firmware or any combination thereof, and may use circuits, single or multiple Application Specific Integrated Circuits (ASICs), single or multiple general purpose integrated circuits, single or multiple microprocessors, single or multiple programmable logic devices, or any combination of the aforementioned circuits and/or devices, or other suitable circuits or devices, so that the processor 140 may perform the respective steps of the methods in the various embodiments of the present description.

It should be understood that the components included in the ultrasound device 10 shown in FIG. 1 are merely illustrative and that more or fewer components may be included. For example, the ultrasound device 10 may also include input devices such as a keyboard, mouse, scroll wheel, trackball, etc., and/or may include output devices such as a printer. The corresponding external input/output port may be a wireless communication module, a wired communication module, or a combination of both. The external input/output port may also be implemented based on USB, bus protocols such as CAN, and/or wired network protocols, etc. The invention is not limited in this regard.

The method of ultrasound contrast imaging in an embodiment of the present invention will be described below with reference to fig. 2 to 8.

Fig. 2 is a schematic flow chart of an ultrasound contrast imaging method according to an embodiment of the present invention. The method shown in fig. 2 comprises:

s10, the ultrasound probe is excited with a target transmission voltage to transmit an ultrasonic beam to a target object perfused with a contrast agent, wherein the target transmission voltage is determined according to the gear adjustment of the acoustic power by the user, and the corresponding voltage variation between adjacent gears is not uniform.

And S20, receiving the ultrasonic echo returned from the target object to obtain an ultrasonic echo signal.

And S30, obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal.

In an embodiment of the present invention, the target object may include a target organ or tissue to be detected, such as a liver, a kidney, a breast, and the like.

In embodiments of the present invention, an ultrasound contrast agent may be injected into the target object (e.g., intravenously), and then the ultrasound contrast agent may enter the target organ or tissue with the blood flow. An ultrasound contrast movie may be generated by dynamically ultrasonically acquiring the procedure, wherein the ultrasound contrast movie includes a plurality of frames of ultrasound contrast images.

It will be appreciated that the method process shown in fig. 2 may be performed by means of an ultrasound apparatus 10 as shown in fig. 1, or the method process shown in fig. 2 may also be implemented by means of an ultrasound system as shown in fig. 3.

In the ultrasound system shown in fig. 3, the beam forming controller may calculate the transmission delay of each array element according to the transmission focus and the transmission aperture, and then the ultrasound system sequentially sends out excitation to the array ultrasound transducer with pulse waves of certain amplitude voltage within a safe range, electrical signals are converted into acoustic signals through piezoelectric conversion, and the ultrasound transducer transmits ultrasound waves to the tissue to be detected. The ultrasonic wave meets the reflection or scattering of the internal structure of the tissue, echo signals at different depths can return to the ultrasonic transducer successively, the acoustic signals are converted into electric signals through piezoelectric conversion, and the echo signals received by the receiving circuit are converted into digital signals through low noise amplification, analog gain compensation and A/D conversion. And according to the receiving delay of the apertures corresponding to different depths given by the beam synthesizer, the receiving beam synthesizer carries out beam synthesis operation on the echo data of each array element to obtain an ultrasonic beam synthesis signal, and then continues to process each link at the rear end to finally obtain the ultrasonic image.

For the method shown in fig. 2, in one implementation, as shown in fig. 4, S11 may be included after S10, and S20 may include S21 and S22.

And S11, determining the front-end analog gain according to the gear adjustment of the user on the sound power.

And S21, receiving the ultrasonic echo returned from the target object based on the front-end simulation gain.

And S22, processing the ultrasonic echo to obtain an ultrasonic echo signal.

Illustratively, the portions of S11 and S21 related to front-end analog Gain may be implemented in conjunction with Time Gain Compensation (TGC) shown in fig. 3.

It will be appreciated that in order to adjust the sound power, in particular a gear may be set to adjust the sound power. Variations in parameters such as transmit waveform, transmit aperture and transmit voltage cause changes in acoustic power. In the present application it can be assumed that the transmit waveform and the transmit aperture are fixed, i.e. the adjustment of the acoustic power in the present application is achieved by adjusting the transmit voltage. That is to say, the user can adjust transmission voltage and then adjust the acoustic power by changing the gear, and the adjustment to transmission voltage and the adjustment to acoustic power in this application are basically equivalent.

The predetermined voltage range can be adjusted, for example, by a certain number of gears. The predetermined voltage range is determined by the system, and may be an output voltage range of a main power supply module of the system, wherein the maximum output voltage related to the output voltage range is defined by a safety range of the system, and it is understood that the maximum output voltage is a transmission voltage corresponding to the maximum acoustic power in the contrast mode. For example, the output voltage range may be 2V to 100V, which is represented as a closed interval [2V,100V ]. The number of gears (i.e., the total number of gears) may be preset according to a scene requirement, and is used to implement fine adjustment of the voltage, for example, the total number of gears may be 50 gears or 100 gears, and the embodiment of the present invention is not limited thereto.

The voltage is divided by the gears in an uneven manner, i.e. there are at least two different gear intervals in which the voltage changes are not equal. For example, the voltage change corresponding to the shift from the M1 th gear to the M1+1 th gear is not equal to the voltage change corresponding to the shift from the M2 th gear to the M2+1 th gear, where M2 is not equal to M1.

As an implementation, the voltage changes corresponding to any two different gear intervals are not equal. This manner of staging may be referred to as a non-uniform spacing. In this way, finer stepping quantization of the output voltage range of the system can be achieved.

In one implementation, the smaller the transmission voltage, the smaller the voltage change that is adjusted between two adjacent gears. That is, for the same voltage range, the number of steps to adjust for the small voltage range is greater than the number of steps to adjust for the large voltage range. In terms of distance, for [ V1, V1+ Δ V ] and [ V2, V2+ Δ V ], if V1< V2, the number of gear steps adjusted for [ V1, V1+ Δ V ] is greater, while the number of gear steps adjusted for [ V2, V2+ Δ V ] is less. It can be seen that more gear steps can be allocated to the low voltage portion, while relatively fewer gear steps can be allocated to the high voltage portion. Therefore, when the working range of the contrast mode is low in voltage, a user can select adjustment as many as possible in the low-voltage range, and the influence on the intensity of echo signals and further on the CTR and the penetrating power of a contrast image due to too large voltage change is avoided.

In one embodiment, the transmission voltage and the gear may satisfy a logarithmic curve relationship. If the total number of gears is represented as N, the maximum voltage of the transmission voltage range is represented as Vmax, and the voltage corresponding to each gear is represented as v (N), where N is 1,2, …, N. And V (1) ═ Vmax. If the voltage of each gear is decreased by Δ dB from gear to gear based on Vmax (i.e., 0dB for the maximum voltage), the logarithmic curve relationship between the transmission voltage and the gear can be expressed as:

V(n)＝Vmax×10^(1-n)×Δ/20，n＝1,2,…,N。

wherein Vmax is determined according to regulatory requirements for a particular ultrasound imaging system. N and Δ can then be set as desired. For example, when N is 101 and Δ is 0.3, β (N) represents a dB value corresponding to the division of each step voltage by the maximum voltage:

β (1) ═ 0dB, which indicates that voltage V (1) ═ Vmax corresponding to the shift position (i.e., n ═ 1) when Acoustic Power (AP) is maximum;

β(101)＝(1-N)*Δ＝-30dB。

further, if Vmax is 100V, V (1) is 100V, and V (101) is 3.16V, which can be calculated from the above equation. Illustratively, the logarithmic curve relationship between the transmission voltage and the shift position is shown in fig. 5, in which the X axis represents the shift position and the Y axis represents the transmission voltage, wherein it is shown that when the shift position is 48 (i.e., X ═ 48), the corresponding transmission voltage is 19.72V (i.e., Y ═ 19.72).

It can be understood that when the transmission voltage and the shift position satisfy the logarithmic curve relationship, in conjunction with the example shown in fig. 5, the voltage change (also referred to as voltage interval) between adjacent shift positions is unequal, the voltage interval of the low-voltage portion is smaller than that of the high-voltage portion, and the number of shift positions in the low-voltage range is much greater than that of the high-voltage portion. Specifically, in fig. 5, after the gear shifting is performed by such non-uniform intervals, there are 54 gears with voltage lower than 20V, that is, for the voltage range of [3.16V,100V ], although the ratio of [3.16V,20V ] is only (20-3.16)/(100-3.16) to 17.39%, the ratio of the number of gears is 54/101 to 53.5%, and the ratio of the total gears exceeds 50%.

It is understood that the target transmission voltage used for exciting the ultrasonic probe in S10 is determined according to the adjustment of the shift position by the user and based on the correspondence between the transmission voltage and the shift position. Taking the corresponding relation shown in fig. 5 as an example, if the user selects the gear 48 by adjustment, the target transmission voltage is 19.72V; if the user selects gear 1 by adjustment, the target transmission voltage is 100V.

Therefore, the method can realize the nonlinear stepping adjustment of the transmitting voltage, wherein the low-voltage part is finely divided, so that when the ultrasonic imaging system works in the radiography mode, a user has more operation space and choice, and the user can not make a dilemma between that microbubbles are broken and the signal-to-noise ratio of the radiography image is not enough. And because in the low voltage scope, the gear adjustment is less to voltage variation to when reducing voltage through the gear, can not lead to transmitting energy to be reduced excessively, and then also ensured echo signal's intensity, further guaranteed the CTR and the penetrating power of contrast image.

In one implementation, S20 may include: and acquiring a preset analog gain, and receiving the ultrasonic echo based on the preset analog gain.

For example, referring to fig. 3, the echo signal of the ultrasonic transducer received by the receiving circuit is subjected to a Gain adjustment or compensation process with depth after low-noise amplification and before a/D analog-to-digital conversion, i.e., a Time Gain Compensation (TGC) element in fig. 3. Because the signal intensity of an ultrasound wave propagates through tissue with increasing depth, generally speaking, for a tissue with a fixed acoustic impedance, the intensity of a sound wave at a fixed frequency is attenuated in proportion to the depth, and the further the ultrasound wave propagates through the tissue, the more the signal amplitude is reduced. For example, the attenuation coefficient of normal human liver tissue is about 0.5dB/Mhz/cm, and when 4MHz ultrasonic signals are used for liver imaging, the attenuation rule of the signals propagating in the ultrasonic signals is as follows: the signal strength decreases by 2dB for every 1cm of forward propagation. Therefore, a preset analog gain can be set in advance based on this principle, as shown in fig. 6. In fig. 6, the abscissa indicates the depth and the ordinate indicates the value of gain compensation, wherein the curve indicates the preset analog gain. Specifically, the gain is gradually increased with the increase of the depth from the tissue surface (the depth is 0), the maximum value of the gain (e.g. g0 in fig. 6) is the upper limit of the system front end design, and the slope is determined according to the attenuation coefficient of the ultrasonic imaging target. Wherein in the range of 0 to d0, the gain increases with increasing depth, and the two are in a linear relationship; at depths greater than d0, the gain is equal to the upper limit g 0.

It should be noted that the curve of the preset analog gain shown in fig. 6 is schematic and should not be construed as a limitation in the present application, for example, the preset analog gain at a depth of 0 may be greater than 0. For example, in the range of 0 to d0, the relationship between the preset analog gain and the depth may not be linear. For example, in a depth range from 0 to a depth greater than 0, the preset analog gain is all equal to 0. For example, the preset analog gain at depth d0 may be less than the upper limit g 0.

In another implementation, as shown in fig. 4, S20 includes S11 before S20 includes S21 and S22. The front-end analog gain is thus determined from the gear adjustment of the acoustic power, i.e. the front-end analog gain is determined dynamically and is no longer fixed.

Exemplarily, S11 may include: acquiring a preset analog gain; and according to the gear adjustment of the sound power, the front-end analog gain is obtained by integral increase or decrease on the basis of the preset analog gain.

The overall increase can be understood as the front-end analog gain is greater than the preset analog gain at any depth, and the difference between the two is equal at any depth. The overall reduction is understood to mean that at any depth, the front-end analog gain is less than the preset analog gain, and the difference between the two is equal at any depth.

For scenes with increased acoustic power: the sound power increase is realized by increasing the transmitting voltage, and the preset analog gain can be reduced integrally according to the magnitude of the increased transmitting voltage to obtain the front-end analog gain. Wherein the front-end analog gain from the first depth to the second depth is incremental, and the front-end analog gain at the second depth is less than or equal to an upper limit, the first depth is less than the second depth, and the upper limit is determined by a system front-end design.

Optionally, if the front-end analog gains of the depth 0 to first depth interval are all zero after the above overall reduction, then further back-end digital gains may be determined such that: the total gain obtained by the front-end analog gain and the back-end digital gain satisfies: the total gain at zero depth is negative, the total gain at the first depth is zero, the total gain at the second depth and greater is less than or equal to the upper limit, and the total gain is increasing with increasing depth over a range of depths from zero to the second depth. It is understood that the back-end digital gain is used to determine the gain compensation for the range of depth 0 to the first depth.

For a reduced acoustic power scenario: the acoustic power is reduced by reducing the transmitting voltage, and the preset analog gain is integrally increased according to the reduced transmitting voltage to obtain the front-end analog gain, wherein the front-end analog gain from zero to a third depth is increased, and the front-end analog gain at the third depth is less than or equal to an upper limit determined by the system front-end design.

Optionally, if the front-end analog gain at the third depth and greater is the upper limit after the overall increase, then further back-end digital gains may be determined such that: the total gain obtained by the front-end analog gain and the back-end digital gain satisfies: the total gain at depths from zero to the fourth depth is incremental, and the total gain at the fourth depth and greater is greater than the upper limit, the third depth being less than the fourth depth. It can be appreciated that the back-end digital gain is used to determine gain compensation at the third depth as well as at greater depths.

A specific implementation of the embodiment of the present invention is described below with reference to fig. 7 and 8 by taking the preset analog gain shown in fig. 6 as an example.

Specifically, S11 may include: acquiring a preset analog gain; if the gear adjustment of the user on the sound power indicates that the sound power is increased, the preset analog gain is wholly reduced to obtain the front-end analog gain; if the user's gear adjustment of the acoustic power indicates a decrease in the acoustic power, the front-end analog gain is obtained by increasing the preset analog gain as a whole.

Wherein the increase in acoustic power is achieved by increasing the transmit voltage, as described above in connection with S10. Accordingly, the preset analog gain can be reduced as a whole according to the magnitude of the increased transmission voltage to obtain the front-end analog gain, wherein the front-end analog gain at the first depth is zero, the front-end analog gain at the second depth is an upper limit, the first depth is smaller than the second depth, and the upper limit is determined by the system front-end design. In connection with fig. 7, the first depth may be denoted as d1, the second depth may be denoted as d2, and d1< d 2. Thus, after the preset analog gain is reduced as a whole, the front-end analog gain is zero when the depth is 0 to d 1. When the depth is d 1-d 2, the front-end analog gain and the change of the depth are in a linear relationship, and the slope is equal to the slope of the preset analog gain. When the depth is greater than d2, the front-end analog gain is upper-limited (i.e., g 0).

Similarly, as described above in connection with S10, the acoustic power reduction is achieved by reducing the transmit voltage. Accordingly, the preset analog gain can be increased as a whole according to the magnitude of the reduced transmission voltage to obtain the front-end analog gain, wherein the front-end analog gain at the zero depth is a first positive value, the front-end analog gain at the third depth is an upper limit, the first positive value is smaller than the upper limit, and the upper limit is determined by the front-end design of the system. In connection with fig. 7, the first positive value may be denoted as g1, the third depth as d3, and g1< g 0. Thus, after the preset analog gain is increased as a whole, when the depth is 0, the front-end analog gain is g 1. When the depth is 0 to d3, the front-end analog gain and the change of the depth are in a linear relationship, and the slope is equal to the slope of the preset analog gain. When the depth is greater than d3, the front-end analog gain is upper-limited (i.e., g 0).

It will be appreciated that, in general, d3< d2, but the size relationship between d3 and d1 is not limiting and is related at least to the following factors: slope, magnitude of voltage change, etc. In addition, the maximum and minimum values of the preset analog gain to be increased or decreased as a whole are defined by the design values of the receiving circuit. That is, the maximum values of d1, d2, d3, and g1 above are defined by the receive circuit design values.

It can be seen that as the acoustic power increases or decreases, the preset analog gain can be decreased or increased overall to obtain the front-end analog gain accordingly. The value of the decrease or increase of the front-end analog gain may be determined according to the above-mentioned gradual change decibel Δ or may be a flexibly configured variable for each shift position. The values of the overall reduction or increase of the front-end analog gain may be equal or unequal for different adjacent gears, which is not limited in the present application. For example, the adjustment from gear M1 to gear M1+1 causes the firing voltage to decrease, thereby increasing the front-end analog gain as a whole, assuming that the value of the overall increase is g 11. The adjustment from gear M2 to gear M2+1 causes the firing voltage to decrease, thereby increasing the front end analog gain as a whole, assuming that the value of the overall increase is g 12. Then g11 and g12 may or may not be equal. Wherein M2 is not equal to M1.

In this way, for a multi-level acoustic output ultrasound system, the user can adjust the gear of the acoustic power of the system. The most typical application scenario is an ultrasound contrast imaging mode in which the system operates in the low voltage range in order to prevent the ultrasound contrast agent in the imaging slice from being knocked down. In daily examinations, patients of different sizes and lesions of different depths are faced, so that the user needs to adjust the shift of the acoustic power in a targeted manner to balance the imaging penetration force and the duration of the microbubbles. While the shift of the acoustic power is adjusted, the contrast image brightness must change if the gain compensation remains unchanged. By changing the front-end analog gain according to the shift adjustment of the acoustic power as described above in connection with S11, compensation for a change in the transmission voltage can be achieved, thereby reducing the degree of change in the brightness of the ultrasound contrast image.

As described above, front-end analog gain compensation can be implemented in the front-end processing section in conjunction with the TGC element in fig. 3. However, since the upper limit and the lower limit of the front-end analog gain cannot be changed (e.g., g0 and 0 are the upper limit and the lower limit of the front-end analog gain in fig. 7), it may affect the uniformity of the whole ultrasound contrast image. Illustratively, in conjunction with fig. 3, a digital gain compensation mechanism may be designed in the "B/M signal processing" stage of the back-end processing section to further adjust the overall uniformity of the ultrasound contrast image.

For example, the back-end digital gain may be determined such that a difference between a total gain obtained by the front-end analog gain and the back-end digital gain and a preset analog gain is a fixed value. For example, when the acoustic power is reduced (i.e., the transmit voltage is reduced), the difference between the total gain obtained and the preset analog gain is equal at any depth. As another example, as the acoustic power increases (i.e., the transmit voltage increases), the difference between the total gain obtained and the preset analog gain is equal at any depth between 0 and d0 (shown in fig. 6).

Specifically, in the implementation shown in fig. 4, after determining the front-end analog gain as the acoustic power increases, it is also possible to: determining the back-end digital gain so that the total gain obtained by the front-end analog gain and the back-end digital gain satisfies: the total gain at the depth of zero is negative, the total gain at the first depth is zero, the total gain at the second depth and greater is upper-limited, and in the range of the depth from zero to the second depth, the total gain varies linearly with the depth and the slope is determined according to the attenuation coefficient of the ultrasonic imaging target.

In connection with fig. 8, the total gain at depth 0 is g3, and g3< 0. And, in the range interval of the depth 0 to d1, the total gain is determined based on the back-end digital gain. Illustratively, in the range of depth 0 to d2, the total gain increases with increasing depth, which is linear. In the range where the depth is greater than d2, the overall gain is equal to the upper limit g 0.

Specifically, in the implementation shown in fig. 4, after determining the front-end analog gain as the acoustic power decreases, it is also possible to: determining the back-end digital gain so that the total gain obtained by the front-end analog gain and the back-end digital gain satisfies: the total gain at the depth of zero is a first positive value, the total gain at the third depth is an upper limit, the total gain at the fourth depth and greater depths is a second positive value, the second positive value is greater than the upper limit, the third depth is less than the fourth depth, and in the range of the depth from zero to the fourth depth, the total gain and the depth change linearly and the slope is determined according to the attenuation coefficient of the ultrasonic imaging target.

In connection with FIG. 8, the overall gain at depth 0 is g1, and g1> 0. And, in the range section where the depth is greater than d3, the total gain is determined based on the back-end digital gain. Illustratively, in the range of depth 0 to d4, the total gain increases with increasing depth, which is linear. In the range where the depth is greater than d4, the overall gain is equal to g2, and g2> g 0.

Therefore, the method and the device can perform back-end digital gain compensation on the basis of front-end analog gain, and further can ensure the integral uniformity of the ultrasonic contrast images.

With the above-mentioned embodiments in conjunction with fig. 2 to 8, in the ultrasound contrast imaging method in the embodiment of the present invention, along with the adjustment of the acoustic power gear by the user, the adjustment of the transmission voltage can be implemented, and the transmission voltage is not uniform with the change of the gear. And because in the low voltage scope, the gear adjustment is less to voltage variation to when reducing voltage through the gear, can not lead to transmitting energy to be reduced excessively, and then also ensured echo signal's intensity, further guaranteed the CTR and the penetrating power of contrast image. Further, the front-end analog gain and the back-end digital gain may be adjusted based on the user's adjustment of the acoustic power level, and as described above in conjunction with fig. 7 and 8, the front-end analog gain may be preferentially adjusted within the upper and lower limits (0 to g0) of the analog gain, and the back-end digital gain (g3 to 0, g0 to g2) may be adjusted for portions exceeding the upper and lower limits (0 to g0) of the analog gain. Therefore, the total gain of the receiving end can be automatically adjusted along with the adjustment of the user on the sound power gear, and the brightness jump of the ultrasonic contrast image caused by the change of the microbubble echo intensity caused by the change of the transmitting voltage is avoided.

Returning now to the ultrasound device 10 shown in figure 1.

In one implementation, the transmit/receive selection switch 120 may excite the ultrasound probe 110 at a target transmit voltage to transmit an ultrasound beam to a target object perfused with a contrast agent via the transmit circuit 160 and receive an ultrasound echo of the ultrasound beam returned from the target object via the receive circuit 170. The processor 140 may obtain an ultrasound echo signal based on the ultrasound echo; and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal. Wherein the target transmission voltage is determined according to the gear adjustment of the sound power by the user, and the corresponding voltage variation between adjacent gears is not uniform. The display 150 may display an ultrasound contrast image of the target object.

In one implementation, the transmit/receive selection switch 120 may excite the ultrasound probe 110 at a target transmit voltage to transmit an ultrasound beam to a target object infused with a contrast agent via the transmit circuit 160, wherein the target transmit voltage is determined according to a user's gear adjustment of the acoustic power, and corresponding voltage variation between adjacent gears is non-uniform. The processor 140 may determine the front-end analog gain based on a user step adjustment to the acoustic power. The transmission/reception selection switch 120 may receive an ultrasonic echo of an ultrasonic beam returned from the target object via the reception circuit 170. The processor 140 may process the ultrasonic echo to obtain an ultrasonic echo signal; and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal. The display 150 may display an ultrasound contrast image of the target object.

In addition, the embodiment of the invention also provides a computer storage medium, and the computer storage medium is stored with the computer program. The computer program, when executed by a computer or processor, may implement the steps of the method described above in connection with fig. 2 or 4. For example, the computer storage medium is a computer-readable storage medium.

In one embodiment, the computer program instructions, when executed by a computer or processor, cause the computer or processor to perform the steps of: exciting an ultrasonic probe with a target transmitting voltage to transmit ultrasonic beams to a target object which is perfused with a contrast agent, wherein the target transmitting voltage is determined according to the gear adjustment of a user on the sound power, and the corresponding voltage variation between adjacent gears is not uniform; receiving an ultrasonic echo returned from a target object to obtain an ultrasonic echo signal; and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal.

In one embodiment, the computer program instructions, when executed by a computer or processor, cause the computer or processor to perform the steps of: exciting an ultrasonic probe with a target transmitting voltage to transmit ultrasonic beams to a target object which is perfused with a contrast agent, wherein the target transmitting voltage is determined according to the gear adjustment of a user on the sound power, and the corresponding voltage variation between adjacent gears is not uniform; determining front-end analog gain according to the gear adjustment of the user on the sound power; receiving an ultrasonic echo returned from the target object based on the front-end analog gain; processing the ultrasonic echo to obtain an ultrasonic echo signal; and obtaining an ultrasonic contrast image of the target object according to the ultrasonic echo signal.

The computer storage medium may include, for example, a memory card of a smart phone, a storage component of a tablet computer, a hard disk of a personal computer, a Read Only Memory (ROM), an Erasable Programmable Read Only Memory (EPROM), a portable compact disc read only memory (CD-ROM), a USB memory, or any combination of the above storage media. The computer-readable storage medium may be any combination of one or more computer-readable storage media.

In addition, the embodiment of the present invention also provides a computer program product, which contains instructions that, when executed by a computer, cause the computer to execute the steps of the method described above in conjunction with fig. 2 or fig. 4.

Therefore, in the embodiment of the invention, along with the adjustment of the sound power gear by the user, the adjustment of the transmission voltage can be realized, and the transmission voltage is not uniform along with the change of the gear. And because in the low voltage scope, the gear adjustment is less to voltage variation to when reducing voltage through the gear, can not lead to transmitting energy to be reduced excessively, and then also ensured echo signal's intensity, further guaranteed the CTR and the penetrating power of contrast image. Further, the front-end analog gain and the back-end digital gain may be adjusted based on the user's adjustment of the acoustic power level, and as described above in conjunction with fig. 7 and 8, the front-end analog gain may be preferentially adjusted within the upper and lower limits (0 to g0) of the analog gain, and the back-end digital gain (g3 to 0, g0 to g2) may be adjusted for portions exceeding the upper and lower limits (0 to g0) of the analog gain. Therefore, the total gain of the receiving end can be automatically adjusted along with the adjustment of the user on the sound power gear, and the brightness jump of the ultrasonic contrast image caused by the change of the microbubble echo intensity caused by the change of the transmitting voltage is avoided.

Although the illustrative embodiments have been described herein with reference to the accompanying drawings, it is to be understood that the foregoing illustrative embodiments are merely exemplary and are not intended to limit the scope of the invention thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the scope or spirit of the present invention. All such changes and modifications are intended to be included within the scope of the present invention as set forth in the appended claims.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described device embodiments are merely illustrative, and for example, the division of the units is only one logical functional division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another device, or some features may be omitted, or not executed.

In the description provided herein, numerous specific details are set forth. It is understood, however, that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure an understanding of this description.

Similarly, it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the invention and aiding in the understanding of one or more of the various inventive aspects. However, the method of the present invention should not be construed to reflect the intent: that the invention as claimed requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

It will be understood by those skilled in the art that all of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and all of the processes or elements of any method or apparatus so disclosed, may be combined in any combination, except combinations where such features are mutually exclusive. Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that while some embodiments described herein include some features included in other embodiments, rather than other features, combinations of features of different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments may be used in any combination.

The various component embodiments of the invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art will appreciate that a microprocessor or Digital Signal Processor (DSP) may be used in practice to implement some or all of the functions of some of the modules in an item analysis apparatus according to embodiments of the present invention. The present invention may also be embodied as apparatus programs (e.g., computer programs and computer program products) for performing a portion or all of the methods described herein. Such programs implementing the present invention may be stored on computer-readable media or may be in the form of one or more signals. Such a signal may be downloaded from an internet website or provided on a carrier signal or in any other form.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

The above description is only for the specific embodiment of the present invention or the description thereof, and the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and the changes or substitutions should be covered within the protection scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method of ultrasound contrast imaging, comprising:

processing the ultrasonic echo to obtain an ultrasonic echo signal;

2. The method of claim 1, wherein determining a front-end analog gain based on a user gear adjustment of acoustic power comprises:

acquiring a preset analog gain;

if the gear adjustment of the user on the sound power indicates that the sound power is increased, the front-end analog gain is obtained by integrally reducing the preset analog gain;

and if the gear adjustment of the user on the sound power shows that the sound power is reduced, the front-end analog gain is obtained by integrally increasing the preset analog gain.

3. The method of claim 2, wherein the acoustic power increase is achieved by increasing a transmit voltage, and the preset analog gain is reduced to the front-end analog gain as a whole according to the magnitude of the increased transmit voltage, wherein the front-end analog gain from a first depth to a second depth is increased, and the front-end analog gain at the second depth is smaller than or equal to an upper limit, the first depth is smaller than the second depth, and the upper limit is determined by a system front-end design.

4. The method of claim 3, wherein processing the ultrasound echoes comprises:

determining a back-end digital gain such that a total gain obtained by the front-end analog gain and the back-end digital gain satisfies:

the total gain at zero depth is negative, the total gain at the first depth is zero, the total gain at the second depth and greater is less than or equal to the upper limit, and the total gain is increasing with increasing depth over a range of depths from zero to the second depth.

5. The method of claim 2, wherein the acoustic power reduction is achieved by reducing a transmit voltage, and the preset analog gain is increased as a whole to obtain the front-end analog gain according to the reduced transmit voltage, wherein the front-end analog gain from zero to a third depth is increased, and the front-end analog gain at the third depth is smaller than or equal to an upper limit determined by a system front-end design.

6. The method of claim 5, wherein processing the ultrasound echoes comprises:

the total gain at depths from zero to a fourth depth is incremental, and the total gain at the fourth depth and greater is greater than the upper limit, the third depth being less than the fourth depth.

7. Method according to one of claims 1 to 6, characterized in that the smaller the transmission voltage, the smaller the voltage change adjusted between two adjacent gears.

8. The method according to any one of claims 1 to 7, characterized in that a logarithmic curve relationship is satisfied between the transmission voltage and the gear.

9. A method of ultrasound contrast imaging, comprising:

10. Method according to claim 9, characterized in that the step of the acoustic power is used to achieve an adjustment of the acoustic power by adjusting the transmission voltage.

11. Method according to claim 9 or 10, characterized in that the smaller the transmission voltage, the smaller the voltage change adjusted between two adjacent gears.

12. The method according to any one of claims 9 to 11, characterized in that a logarithmic curve relationship is satisfied between the transmission voltage and the gear.

13. An ultrasound device, comprising:

an ultrasonic probe;

a memory for storing a program executed by the processor;

a display for displaying the ultrasound contrast image.

14. A computer storage medium on which a computer program is stored, characterized in that the computer program, when being executed by a computer or a processor, carries out the steps of the method of any one of claims 1 to 12.