CN112294354A

CN112294354A - Ultrasound imaging method and system

Info

Publication number: CN112294354A
Application number: CN201910712393.1A
Authority: CN
Inventors: 向兰茜; 杨波; 范伟
Original assignee: Shenzhen Mindray Bio Medical Electronics Co Ltd
Current assignee: Shenzhen Mindray Bio Medical Electronics Co Ltd
Priority date: 2019-08-02
Filing date: 2019-08-02
Publication date: 2021-02-02
Anticipated expiration: 2039-08-02
Also published as: CN112294354B

Abstract

The invention provides an ultrasonic imaging method and system, comprising the following steps: transmitting a first ultrasonic wave of a first time and a focused ultrasonic wave of a second time to a scanning target, wherein the area of an imaging area of the scanning target covered by the first ultrasonic wave transmitted each time is larger than the area of the imaging area of the scanning target covered by the focused ultrasonic wave transmitted each time; respectively receiving echoes of the first ultrasonic waves transmitted each time to obtain one or more groups of first ultrasonic echo signals; respectively receiving echoes of the focused ultrasonic waves transmitted each time to obtain a plurality of groups of second ultrasonic echo signals; acquiring a fundamental component of one or more groups of first ultrasonic echo signals, and acquiring a first ultrasonic image of at least one part of a scanning target according to the fundamental component; obtaining harmonic components of a plurality of groups of second ultrasonic echo signals, and obtaining a second ultrasonic image of at least one part of a scanning target according to the harmonic components; a target ultrasound image of a frame of at least a portion of the scan target is obtained from the first ultrasound image and the second ultrasound image.

Description

Ultrasound imaging method and system

Technical Field

The present invention relates generally to the field of ultrasound imaging technology, and more particularly to an ultrasound imaging method and system.

Background

Ultrasonic tissue harmonic imaging is carried out by transmitting an excitation waveform with the frequency of f0, due to the nonlinear effect of sound waves in the process of human tissue propagation, a series of harmonic components exist in echo signals, and second harmonic (the central frequency is 2 x f0) frequency components in the echo signals are extracted for ultrasonic imaging. Compared with the traditional fundamental wave imaging, the harmonic wave imaging has better contrast resolution and lateral resolution, and can provide information which is more different from normal tissues for some focuses. But since the harmonics have twice the frequency of the corresponding fundamental, higher frequencies mean greater tissue attenuation. For deeper probing, pure harmonic imaging suffers from insufficient penetration in the far field. In order to give consideration to both the high contrast resolution of harmonic waves and the high penetration of fundamental waves, the target tissue can be imaged by respectively adopting two different frequency components of the harmonic waves and the fundamental waves, and then the images with two different frequencies are compounded to obtain a final display image, wherein the imaging method is called as a frequency compound imaging method.

The existing frequency composite imaging method adopts focused waves to perform line-by-line scanning, the scanning sequence is shown in fig. 2, a focused wave mode is adopted, each time of emission can only cover a relatively narrow area to obtain 'one line' of received data, the emission and receiving positions are sequentially shifted to the right, and the whole ultrasonic probe coverage area is traversed to obtain a frame of two-dimensional image data.

As shown in fig. 3, in the conventional frequency complex imaging, in order to perform two-dimensional imaging of fundamental waves and harmonic frequencies separately, it is necessary to transmit twice at each transmission position, once for extracting harmonic signals, and once for extracting fundamental wave signals. Assuming that the total number of transmit positions for completing a frame scan is N, 2N transmissions are required to complete a frame imaging in order to achieve frequency compounding. The scanning time of one frame of image is 2 times that of the non-frequency-complex case, that is, the frame rate is reduced to 1/2 in the non-frequency-complex case, and the reduction of the frame rate means the compromise of the time resolution.

Disclosure of Invention

One aspect of the present invention provides an ultrasound imaging method, including:

transmitting a first number of first ultrasonic waves to a scanning target;

respectively receiving echoes of the first ultrasonic waves transmitted each time to obtain one or more groups of first ultrasonic echo signals;

transmitting focused ultrasonic waves for a second time to the scanning target, wherein the area of an imaging area of the scanning target covered by the first ultrasonic waves transmitted each time is larger than the area of the imaging area of the scanning target covered by the focused ultrasonic waves transmitted each time;

respectively receiving echoes of the focused ultrasonic waves transmitted each time to obtain a plurality of groups of second ultrasonic echo signals;

acquiring a fundamental component of the one or more groups of first ultrasonic echo signals, and acquiring a first ultrasonic image of at least one part of the scanning target according to the fundamental component;

obtaining harmonic components of the multiple groups of second ultrasonic echo signals, and obtaining a second ultrasonic image of at least one part of the scanning target according to the harmonic components; and

a target ultrasound image of a frame of at least a portion of the scan target is obtained from the first and second ultrasound images.

Yet another aspect of the present invention provides an ultrasound imaging system comprising:

a probe;

the transmitting circuit is used for exciting the probe to transmit a first ultrasonic wave for a first time to a scanning target and transmit a focused ultrasonic wave for a second time to the scanning target, wherein the area of an imaging area of the scanning target covered by the first ultrasonic wave transmitted each time is larger than the area of the imaging area of the scanning target covered by the focused ultrasonic wave transmitted each time;

the receiving circuit and the beam synthesis module are used for respectively receiving the echoes of the first ultrasonic waves transmitted each time, obtaining one or more groups of first ultrasonic echo signals, obtaining fundamental wave components of the first ultrasonic echo signals based on the first ultrasonic echo signals, respectively receiving the echoes of the focused ultrasonic waves transmitted each time, obtaining multiple groups of second ultrasonic echo signals, and obtaining harmonic wave components of the second ultrasonic echo signals based on the second ultrasonic echo signals;

a processor to:

obtaining a first ultrasound image of at least a portion of the scan target from a fundamental component of the one or more sets of first ultrasound echo signals,

obtaining a second ultrasound image of at least a portion of the scan target from harmonic components of the plurality of sets of second ultrasound echo signals,

For example, the first ultrasonic wave may be an unfocused ultrasonic wave including at least one of a plane wave and a divergent wave. A single shot of unfocused ultrasound waves may cover the entire imaging area; at this time, one or more times of unfocused ultrasonic waves may be transmitted for fundamental wave imaging. When the unfocused ultrasonic waves are transmitted for multiple times, at least two of the unfocused ultrasonic waves can be controlled to have different deflection angles, and the unfocused ultrasonic waves can also be controlled to be repeatedly transmitted according to the same propagation direction.

For example, the first ultrasonic wave may be an unfocused ultrasonic wave including at least one of a plane wave and a divergent wave. A single shot of unfocused ultrasound covers a fractional region of the entire imaged region. At this time, the unfocused ultrasonic waves may be emitted a plurality of times for fundamental wave imaging, and the composite scanning range of the unfocused ultrasonic waves a plurality of times covers the entire imaging region. The multiple transmissions of the at least two unfocused ultrasound waves may have different deflection angles; the non-focused ultrasonic waves emitted each time can have an overlap or no overlap with the corresponding scanning partial areas.

For example, the first ultrasonic wave may be a broad beam ultrasonic wave. A single shot of broad beam ultrasound covers a partial region of the entire imaging area. At this time, the fundamental wave imaging may be performed by emitting the wide-beam ultrasonic waves a plurality of times, and the composite scanning range of the wide-beam ultrasonic waves a plurality of times covers the entire imaging region. The multiple transmissions of the at least two wide beam ultrasound waves may have different deflection angles; there may or may not be an overlap between the scanned partial regions corresponding to the wide-beam ultrasonic waves emitted each time.

For example, both the first ultrasound wave transmitted a first number of times and the focused ultrasound wave transmitted a second number of times may cover the entire imaging area. For example, the first ultrasound wave transmitted a first number of times and the focused ultrasound wave transmitted a second number of times may cover only a partial area of the entire imaging area, wherein both cover the same area of the entire imaging area.

According to the ultrasonic imaging method and system of the embodiment of the invention, the fundamental component is extracted by using the first ultrasonic wave, the harmonic component is extracted by using the focused ultrasonic wave, then the first ultrasonic image and the second ultrasonic image which are respectively obtained by the two are compounded to obtain a target ultrasonic image of one frame of at least one part of the scanning target, wherein the area of the imaging region of the scanning target covered by the first ultrasonic wave transmitted each time is larger than the area of the imaging region of the scanning target covered by the focused ultrasonic wave transmitted each time, that is, the number of times of scanning the imaging region by using the first ultrasonic wave is smaller than the number of times of scanning the imaging region by using the focused ultrasonic wave, fundamental imaging with the first ultrasound wave can significantly reduce the total number of transmissions per frame scan, therefore, the scanning frame rate is improved, the time resolution of the ultrasonic imaging system is improved, and the system has better dynamic characteristics.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced 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 to obtain other drawings based on these drawings without inventive labor.

FIG. 1 is a schematic block diagram of an ultrasound imaging system of one embodiment of the present invention;

FIG. 2 is a diagram illustrating a line-by-line scanning scheme of a conventional frequency complex;

FIG. 3 shows a schematic diagram of a scanning sequence for conventional frequency compounding;

FIG. 4 is a schematic diagram illustrating the transmission and reception of plane waves according to one embodiment of the present invention;

FIG. 5 is a schematic diagram showing multiple plane wave launches with different deflection angles imaging the same imaging region according to one embodiment of the invention;

FIG. 6 shows a flow chart of an ultrasound imaging method of one embodiment of the present invention;

FIG. 7 shows a schematic diagram of a frequency complex scan sequence of one embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. It is to be understood that the described embodiments are merely a subset of embodiments of the invention and not all embodiments of the invention, with the understanding that the invention is not limited to the example embodiments described herein. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the invention described herein without inventive step, shall fall within the scope of protection of the invention.

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art, that the present invention may be practiced without one or more of these specific details. In other instances, well-known features have not been described in order to avoid obscuring the invention. It is to be understood that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

In order to provide a thorough understanding of the present invention, a detailed structure will be set forth in the following description in order to explain the present invention. Alternative embodiments of the invention are described in detail below, however, the invention may be practiced in other embodiments that depart from these specific details.

In particular, the ultrasound imaging method and system of the present application are described in detail below with reference to the accompanying drawings. The features of the following examples and embodiments may be combined with each other without conflict.

First, fig. 1 shows a schematic block diagram of an ultrasound imaging system in an embodiment of the present invention. As shown in fig. 1, the ultrasound imaging system generally includes: a probe 1, a transmission circuit 2, a transmission/reception selection switch 3, a reception circuit 4, a beam forming module 5, a processor 6, a display (not shown), and the like.

The processor 6 may be a Central Processing Unit (CPU), image processing unit (GPU), Application Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA) or other form of processing unit having data processing capabilities and/or instruction execution capabilities, and may control other components in the ultrasound imaging system to perform desired functions. For example, the processor 6 can include one or more embedded processors, processor cores, microprocessors, logic circuits, hardware Finite State Machines (FSMs), Digital Signal Processors (DSPs), image processing units (GPUs), or a combination thereof.

In the ultrasonic imaging process, the transmission circuit 2 transmits a delay-focused transmission pulse having a certain amplitude and polarity to the probe 1 through the transmission/reception selection switch 3. The probe 1 is excited by the transmission pulse, transmits an ultrasonic wave to a scanning target (for example, an organ, a tissue, a blood vessel, etc. in a human body or an animal body, not shown in the figure), receives an ultrasonic echo with information of the scanning target, which is reflected and/or scattered from a target region, after a certain time delay, and converts the ultrasonic echo into an electric signal again. The receiving circuit receives the electric signals generated by the conversion of the probe 1, obtains ultrasonic echo signals, and sends the ultrasonic echo signals to the beam forming module 5. The beam-forming module 5 performs processing such as focusing delay, weighting, and channel summation on the ultrasonic echo signals, and then sends the ultrasonic echo signals to the processor 6 for relevant signal processing, for example, the processor 6 includes a signal processing module 7 (e.g., a digital signal processor), and sends the ultrasonic echo signals to the signal processing module 7 for relevant signal processing.

The ultrasonic echo signals processed by the signal processing module 7 are sent to an image processing module 8 (e.g., a Graphic Processing Unit (GPU)). The image processing module performs different processing on the signals according to different imaging modes required by a user to obtain image data of different modes, and then performs processing such as logarithmic compression, dynamic range adjustment, digital scan conversion and the like to form ultrasonic images of different modes, such as a B image, a C image, a D image and the like.

The ultrasound image generated by the image processing module 8 is sent to a display for displaying.

The probe 1 typically comprises an array of a plurality of array elements. At each transmission of the ultrasound wave, all or a part of all the elements of the probe 1 participate in the transmission of the ultrasound wave. At this time, each array element or each part of array elements participating in ultrasonic wave transmission is excited by the transmission pulse and respectively transmits ultrasonic waves, the ultrasonic waves respectively transmitted by the array elements are superposed in the transmission process to form a synthesized ultrasonic wave beam transmitted to a scanning target, and the direction of the synthesized ultrasonic wave beam is the ultrasonic transmission direction mentioned in the text.

The array elements participating in ultrasonic wave transmission can be simultaneously excited by the transmission pulse; alternatively, there may be a delay between the times at which the elements participating in the ultrasound transmission are excited by the transmit pulse. The propagation direction of the above-mentioned composite ultrasound beam can be changed by controlling the time delay between the times at which the array elements participating in the transmission of the ultrasound wave are excited by the transmit pulse, as will be explained in detail below.

By controlling the time delay between the times at which the array elements participating in the transmission of the ultrasound wave are excited by the transmit pulse, the ultrasound waves transmitted by the respective array elements can be superimposed at a predetermined position such that the intensity of the ultrasound wave is maximized at the predetermined position, i.e. the ultrasound waves transmitted by the respective array elements are "focused" at the predetermined position, which is referred to as a "focal point", such that the resulting ultrasound beam obtained is a beam focused at the focal point, referred to herein as a "focused ultrasound wave". For example, fig. 2 is a schematic diagram of transmitting a focused ultrasound beam. Here, the elements participating in the transmission of the ultrasound wave (in fig. 2, only a part of the elements in the probe 1 participate in the transmission of the ultrasound wave) operate with a predetermined transmission delay (i.e., a predetermined delay exists between the times at which the elements participating in the transmission of the ultrasound wave are excited by the transmission pulse), and the ultrasound wave transmitted by each element is focused at the focal point to form a focused ultrasound beam.

Alternatively, by controlling the time delay between the times at which the array elements participating in the transmission of the ultrasonic wave are excited by the transmission pulse, the ultrasonic waves transmitted by the respective array elements participating in the transmission of the ultrasonic wave may not be focused or completely dispersed during propagation, but may form a plane wave which is substantially planar as a whole. Such an afocal plane wave can also be referred to as a "plane ultrasound beam" as shown in fig. 4.

Or, by controlling the time delay between the time when the array elements participating in the transmission of the ultrasonic wave are excited by the transmission pulse, the ultrasonic wave transmitted by each array element participating in the transmission of the ultrasonic wave is diverged in the propagation process, and is generally formed into a divergent wave as a whole. This divergent form of ultrasound may also be referred to as a "divergent ultrasound beam".

A plurality of array elements which are linearly arranged simultaneously excite an electric pulse signal, each array element simultaneously emits ultrasonic waves, and the propagation direction of the synthesized ultrasonic waves is consistent with the normal direction of the array element arrangement plane. For example, in the case of a vertically transmitted plane wave as shown in fig. 4, there is no time delay between the array elements participating in the transmission of the ultrasonic wave (i.e., there is no time delay between the times when the array elements are excited by the transmit pulse), and the array elements are excited simultaneously by the transmit pulse. The generated ultrasonic beam is a plane wave, i.e., a plane ultrasonic beam, and the propagation direction of the plane ultrasonic beam is substantially perpendicular to the surface of the probe 1 from which the ultrasonic wave is emitted, i.e., the angle between the propagation direction of the synthesized ultrasonic beam and the normal direction of the array element arrangement plane is zero degrees. However, if the excitation pulse applied to each array element has a time delay, and each array element sequentially emits the ultrasonic beam according to the time delay, the propagation direction of the synthesized ultrasonic beam has a certain angle with the normal direction of the array element arrangement plane, that is, the deflection angle of the synthesized beam, and by changing the time delay, the magnitude of the deflection angle of the synthesized beam and the deflection direction in the scanning plane of the synthesized beam with respect to the normal direction of the array element arrangement plane can be adjusted. For example, fig. 5 shows the plane waves transmitted by deflection, each dotted line represents the plane waves transmitted each time, there is a predetermined time delay between the array elements participating in the transmission of the ultrasonic wave (i.e. there is a predetermined time delay between the time when the array elements are excited by the transmission pulse), and the array elements are excited by the transmission pulse according to a predetermined sequence. The generated ultrasonic beam is a plane wave, i.e. a plane ultrasonic beam, and the propagation direction of the plane ultrasonic beam forms an angle with the normal direction of the array element arrangement plane of the probe 1, i.e. the deflection angle of the plane ultrasonic beam. By changing the time delay time, the size of the deflection angle can be adjusted.

Similarly, whether it is a plane ultrasonic beam, a focused ultrasonic beam or a divergent ultrasonic beam, the "deflection angle" of the synthesized beam formed between the direction of the synthesized beam and the normal direction of the array element arrangement plane can be adjusted by controlling the time delay between the times at which the array elements participating in the transmission of the ultrasonic wave are excited by the transmission pulse, and the synthesized beam can be the above-mentioned plane ultrasonic beam, focused ultrasonic beam or divergent ultrasonic beam, and so on.

The planar ultrasonic beam generally covers almost the entire imaging region of the probe 1, and thus when the planar ultrasonic beam is used for imaging, one frame of ultrasonic image (this frame of ultrasonic image should be understood to include one frame of two-dimensional image data or one frame of three-dimensional image data, hereinafter) can be obtained with one shot, and thus the imaging frame rate can be high. When the focused ultrasonic beam is used for imaging, because the beam is focused at the focus, only one or a plurality of scanning lines can be obtained each time, and all the scanning lines in the imaging area can be obtained after multiple times of emission, so that all the scanning lines are combined to obtain a frame of ultrasonic image of the imaging area. Therefore, the frame rate is relatively low when imaging with focused ultrasound beams. But the ability of focusing ultrasonic beam is more concentrated at each emission and imaging is only carried out at the concentrated ability, so that the signal-to-noise ratio of the obtained echo signal is high, and an ultrasonic image with better quality can be obtained.

In some embodiments, the scanning region of the planar ultrasonic beam or the divergent ultrasonic beam formed by a single emission can be controlled to only cover a partial region of the whole imaging region, and the scanning results of the planar ultrasonic beam or the emitted ultrasonic beam emitted for a plurality of times are mutually overlapped to obtain a frame of ultrasonic image covering the whole imaging region.

In order to solve the problem that the conventional frequency compounding method has a low frame rate, so that the time resolution is reduced, which affects the efficiency of ultrasonic imaging, the ultrasonic imaging method includes: transmitting a first number of first ultrasonic waves to a scanning target; respectively receiving echoes of the first ultrasonic waves transmitted each time to obtain one or more groups of first ultrasonic echo signals; transmitting focused ultrasonic waves for a second time to the scanning target, wherein the area of an imaging area of the scanning target covered by the first ultrasonic waves transmitted each time is larger than the area of the imaging area of the scanning target covered by the focused ultrasonic waves transmitted each time; respectively receiving echoes of the focused ultrasonic waves transmitted each time to obtain a plurality of groups of second ultrasonic echo signals; acquiring a fundamental component of the one or more groups of first ultrasonic echo signals, and acquiring a first ultrasonic image of at least one part of the scanning target according to the fundamental component; obtaining harmonic components of the multiple groups of second ultrasonic echo signals, and obtaining a second ultrasonic image of at least one part of the scanning target according to the harmonic components; and obtaining a target ultrasound image of a frame of at least a portion of the scan target from the first ultrasound image and the second ultrasound image.

According to the ultrasonic imaging method and system of the embodiment of the invention, the first ultrasonic wave is used for extracting the fundamental wave component, the focused ultrasonic wave is used for extracting the harmonic component, and then the first ultrasonic image and the second ultrasonic image which are respectively obtained by the first ultrasonic wave and the focused ultrasonic wave are compounded to obtain the target ultrasonic image of one frame of at least one part of the scanning target, wherein the area of the imaging area of the scanning target covered by the first ultrasonic wave which is transmitted each time is larger than the area of the imaging area of the scanning target covered by the focused ultrasonic wave which is transmitted each time, namely, the number of times of scanning the imaging area by the first ultrasonic wave is smaller than the number of times of scanning the imaging area by the focused ultrasonic wave, so that the number of times of transmission of scanning each frame can be obviously reduced by the fundamental wave imaging of the first ultrasonic wave, thereby improving the scanning frame rate and further improving the time resolution of, so that the system has better dynamic characteristics.

In the following, the ultrasound imaging method according to an embodiment of the invention is explained and illustrated in detail with continued reference to the drawings.

First, as shown in fig. 7, in step S701, a first ultrasonic wave is emitted to a scan target for a first number of times.

For example, as shown in fig. 1, the transmission circuit excites the probe to transmit a first number of first ultrasonic waves to the scan target. Wherein, each array element in the probe 1 is configured with a corresponding delay line, and the probe is subjected to sound beam control and dynamic focusing by changing the delay time of each array element in the probe 1, so as to obtain different types of synthesized ultrasonic beams or different ultrasonic propagation directions. Optionally, the first ultrasonic wave comprises a non-focused ultrasonic wave or a broad beam ultrasonic wave, wherein the non-focused ultrasonic wave comprises at least one of a plane wave and a divergent wave. The emission of plane waves and diverging waves has been described above and will not be described in detail here.

The type of the transmitted unfocused ultrasonic wave can be selected reasonably according to the type of the probe, for example, when the probe is a linear array probe and the transmitted first ultrasonic wave is the unfocused ultrasonic wave, the unfocused ultrasonic wave is a plane wave, when the probe is a convex array or a phased array probe and the transmitted first ultrasonic wave is the unfocused ultrasonic wave, the unfocused ultrasonic wave is a diverging wave.

For a wide-beam ultrasonic wave, multiple scan lines generally transmit and receive simultaneously, and echo information corresponding to each scan line is called an ultrasonic echo beam.

In this context, the embodiments of the present invention are explained and illustrated mainly in the case where the first ultrasonic wave is a plane wave, but it should be understood that the first ultrasonic wave is not limited to the plane wave.

The number of times (i.e., the first number) of the first ultrasonic waves emitted to the scanning target may be set reasonably according to actual needs, for example, the first ultrasonic waves (e.g., plane waves or diverging waves) may be emitted once to the scanning target to obtain an ultrasonic image of one frame, or the first ultrasonic waves (e.g., plane waves, diverging waves, or wide-beam ultrasonic waves) may be emitted multiple times to the scanning target, and the results of the multiple times of scanning may be combined to obtain an ultrasonic image of one frame.

In one example, the first ultrasonic wave may be transmitted to the scan target a plurality of times, that is, such that the first number of times is greater than or equal to 2, wherein, when the first ultrasonic wave is unfocused ultrasonic wave, such as plane wave or divergent wave, the unfocused ultrasonic wave is transmitted to the scanning target for a plurality of times, and at least two of the emitted unfocused ultrasonic waves have different deflection angles which can be reasonably set according to actual requirements, for example, it can be reasonably selected in the range between (0 degrees, 90 degrees), the echo data obtained by transmitting at different deflection angles is subjected to beam forming, then the re-coherent superposition can improve the contrast and the signal-to-noise ratio of a frame of ultrasonic image finally obtained by transmitting the first ultrasonic wave, therefore, the problem that the image obtained by transmitting the unfocused ultrasonic wave only once has poor transverse resolution and low middle far-field signal-to-noise ratio can be solved.

Optionally, the first ultrasound waves comprise unfocused ultrasound waves; wherein each emitted unfocused ultrasound wave covers the entire imaging area of the scan target. The plane wave shown in fig. 5, for example, can cover the entire imaging area of the scanning target, and thus, it can acquire an ultrasound image of one frame of the imaging area by transmitting it once. At this time, multiple times of unfocused ultrasonic waves (for example, the plane waves shown in fig. 5) are transmitted to the scanning target, and at least two times of the unfocused ultrasonic waves have different deflection angles, the multiple plane waves with different deflection angles are transmitted to image the same region (that is, the same imaging region), and a frame of ultrasound images obtained by transmitting the plane waves in fig. 5 each time are coherently superposed, so that a frame of compounded high-quality ultrasound images can be obtained.

Alternatively, the first ultrasonic wave may be a wide-beam ultrasonic wave covering a part of the imaging region, the wide-beam ultrasonic wave may be transmitted to the scan target multiple times, and at least two of the wide-beam ultrasonic waves transmitted at least twice have different deflection angles, and the deflection angles may be reasonably set according to actual needs, for example, the deflection angles may be reasonably selected within a range between (0 degree and 90 degrees), echo data transmitted at these different deflection angles are beam-synthesized, and then the contrast and the signal-to-noise ratio of a frame of ultrasonic image finally obtained by transmitting the first ultrasonic wave are coherently superimposed.

In this context, the imaging region refers to a region of a scan target to which ultrasound imaging is required, for example, the scan target may be an organ, a tissue, a blood vessel, or the like in a human or animal body. The imaging region (i.e., scanning region) covered by the first ultrasonic wave and the imaging region (scanning region) covered by the focused ultrasonic wave refer to regions corresponding to beams received by the probe for subsequent image processing.

Next, as shown in fig. 7, in step S702, the echoes of the first ultrasonic wave transmitted each time are received, and one or more sets of first ultrasonic echo signals are obtained.

Specifically, the receiving circuit receives echoes of the first ultrasonic waves transmitted in the above steps, and obtains one set of first ultrasonic echo signals every time the first ultrasonic waves are transmitted, for example, obtains one set of first ultrasonic echo signals every time the first ultrasonic waves are transmitted, or obtains multiple sets of first ultrasonic echo signals every time multiple sets of first ultrasonic waves are transmitted.

Next, with continued reference to fig. 7, in step S703, a second number of focused ultrasound waves are emitted toward the scan target, wherein the area of the imaging region of the scan target covered by the first ultrasound wave emitted each time is larger than the area of the imaging region of the scan target covered by the focused ultrasound wave emitted each time.

Specifically, the transmitting circuit excites the probe to transmit the second number of focused ultrasonic waves to the scan target, wherein the transmitting process of the focused ultrasonic waves is not described herein with reference to the foregoing description. The number of times of transmitting the focused ultrasonic waves may be determined according to the range size of the imaging region of the actual scanning target, for example, the second number of times of transmitting the focused ultrasonic waves covers the entire imaging region of the scanning target, that is, each time of transmitting the focused ultrasonic waves covers only a part of the entire imaging region of the scanning target, and the total number of times of transmitting the focused ultrasonic waves covers the entire imaging region of the scanning target, thereby obtaining an ultrasonic image of one frame.

In step S701 and step S703, the focused ultrasound wave of the second time and the first ultrasound wave of the first time are emitted to the same imaging region of the scanning target, so as to ensure that the ultrasound image of one frame of the same imaging region is obtained by the subsequent processing.

Alternatively, since the area of the imaging region of the scan target covered by the first ultrasonic wave per emission is larger than the area of the imaging region of the scan target covered by the focused ultrasonic wave per emission, the first number of times is smaller than the second number of times. The whole imaging area can be covered by transmitting the first ultrasonic waves for a small number of times to obtain one frame of ultrasonic image for the same imaging area, and the first ultrasonic waves for the same number of times do not need to be transmitted for the second time, so that the total time for transmitting the first ultrasonic waves and focusing the ultrasonic waves can be obviously reduced. For example, the first number is 1/100 to 3/4 of the second number, and can be set appropriately according to actual needs.

Next, as shown in fig. 7, in step S704, echoes of the focused ultrasound waves transmitted each time are received, and a plurality of sets of second ultrasound echo signals are obtained.

The step of receiving the echoes of the focused ultrasonic wave reflected and/or scattered by the scanning target from each transmission to obtain a plurality of sets of second ultrasonic echo signals is well known to those skilled in the art and will not be described herein.

It is worth mentioning that the steps of the ultrasound imaging method shown in fig. 7 are only examples in this context, and the order between the various steps may be interchanged under reasonable circumstances, for example, the focused ultrasound wave may be transmitted first and the echo of each transmission thereof may be received, and then the first ultrasound wave may be transmitted and the echo of each transmission thereof may be received, or the transmission and reception of the first ultrasound wave may be interspersed with the transmission and reception steps of the focused ultrasound wave.

If it is intended to transmit the first ultrasonic wave having different deflection angles to the scan target a plurality of times, or if it is intended to transmit the first ultrasonic wave to the scan target a plurality of times, and the first ultrasonic waves have the same deflection angle for the plurality of times, only the transmission is repeated a plurality of times, the first ultrasonic wave and the focused ultrasonic wave may be transmitted in the following order. In one example, the first ultrasonic wave may be continuously transmitted to the scan target until the number of transmissions of the first ultrasonic wave reaches the first number, and then the focused ultrasonic wave may be continuously transmitted to the scan target until the number of transmissions of the focused ultrasonic wave reaches the second number; or continuously transmitting the focused ultrasonic waves to the scanning target until the transmitting times of the focused ultrasonic waves reach the second times, and then continuously transmitting the first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach the first times; or transmitting focused ultrasonic waves of partial times in the second time to the scanning target, continuously transmitting the first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach the first time, and finally transmitting the focused ultrasonic waves of the rest times in the second time to the scanning target. The purpose of continuously transmitting the first ultrasonic waves is to ensure coherence between the transmitted first ultrasonic waves with different deflection angles, so that coherent combination can be conveniently carried out in subsequent processing, and an ultrasonic image with high quality can be obtained.

In the case where the coherence is not taken into consideration, for example, the first ultrasonic wave is scheduled to be transmitted to the scanning target a plurality of times, the first ultrasonic wave having the same deflection angle, and only the transmission is repeated a plurality of times, the first ultrasonic wave and the focused ultrasonic wave may also be transmitted in the following order. In one example, the first ultrasonic wave and the focused ultrasonic wave are alternately transmitted to the scan target until the number of transmissions of the first ultrasonic wave reaches a first number and the number of transmissions of the focused ultrasonic wave reaches a second number, for example, the first ultrasonic wave is transmitted to the scan target at least once after the first ultrasonic wave is transmitted to the scan target at least once, or the first ultrasonic wave is transmitted to the scan target at least once after the focused ultrasonic wave is transmitted to the scan target at least once.

In other examples, the first ultrasonic wave emitted at a time covers only a partial region of the imaging region and the first ultrasonic wave emitted a first number of times to the scan target covers the entire imaging region, for example, in the case where the first ultrasonic wave includes a wide-beam ultrasonic wave, the wide-beam ultrasonic wave emitted at a time covers only a partial region of the imaging region, and the coverage of the entire imaging region is achieved by emitting the wide-beam ultrasonic wave a first number of times, thereby obtaining one-frame ultrasonic image of the imaging region.

Optionally, each time the first ultrasonic wave emitted to the scan target covers a partial region of the entire imaging region, there is no overlap between the partial regions, and for this case, in the subsequent processing, the sub-ultrasonic images obtained by each emission may be spliced, that is, the ultrasonic image of one frame of the imaging region may be obtained. Or, the first ultrasonic wave emitted to the scanning target each time covers a partial region of the whole imaging region, and the partial regions are partially overlapped, for this case, in the subsequent processing, the sub-ultrasonic images obtained by each emission can be spliced, and the overlapped portions are coherently superposed, so that the ultrasonic image of one frame of the imaging region can be obtained.

The transmission order of transmitting the first ultrasonic wave and the focused ultrasonic wave to the scan target may be adjusted according to whether the partial regions overlap with each other or not, in one example, when the partial regions overlap with each other or when the partial regions do not overlap with each other, the first ultrasonic wave is continuously transmitted to the scan target until the number of transmission times reaches the first number, alternatively, the first ultrasonic wave may be continuously transmitted to the first number after the number of transmission times of the focused ultrasonic wave reaches the second number, or the focused ultrasonic wave may be transmitted to the second number after the first ultrasonic wave is continuously transmitted to the first number, or the first ultrasonic wave may be continuously transmitted to the first number after at least one transmission time of the focused ultrasonic wave reaches the second number. In another example, when there is no overlap between the partial regions, the first ultrasonic wave and the focused ultrasonic wave may be transmitted to the scan target alternately, and the process of the alternate transmission is as described above, and is not described herein again.

With continued reference to fig. 7, in step S705, a fundamental component of one or more sets of first ultrasonic echo signals is acquired, and a first ultrasonic image of at least a portion of the scan target is obtained from the fundamental component.

Specifically, the steps of acquiring a fundamental component of a plurality of sets of first ultrasonic echo signals, and obtaining a first ultrasonic image of at least a part of a scan target according to the fundamental component include the following steps a1 to a 4:

in step a1, fundamental wave components are extracted from the sets of first ultrasonic echo signals, respectively. That is, a fundamental component is extracted in each set of the first ultrasonic echo signals, where, herein, the fundamental component refers to an echo signal having a frequency equal to the center frequency of the transmitted ultrasonic wave (also referred to as the fundamental frequency f0), and the harmonic component refers to an echo signal having a frequency equal to any integer multiple of the fundamental frequency, and for the sake of simplicity, it may be assumed that the subsequently extracted harmonic signal is an echo signal having a frequency 2 times the fundamental frequency (also referred to as a harmonic component of order 2). The harmonic signals in each set of first ultrasonic echoes may be removed by, for example, bandwidth-limited filtering (e.g., harmonic filter), and the fundamental component is extracted from each set of first ultrasonic echoes. The fundamental wave has high penetrating power, so that the deep exploration is facilitated.

In step a2, the extracted fundamental components are beamformed to obtain sets of beamformed fundamental echo signals.

The extracted fundamental wave components are beam-synthesized by the beam synthesis module to obtain multiple groups of beam-synthesized fundamental wave echo signals, and the beam synthesis in this step may be performed by any suitable method known to those skilled in the art, for example, the extracted fundamental wave components may be subjected to focusing delay, weighting, channel summation, and other processing to perform beam synthesis on the extracted fundamental wave components, which is not described herein again.

In step a3, multiple sets of sub-ultrasound images of at least a portion of the scan target are obtained respectively based on the multiple sets of beamformed fundamental echo signals.

For example, the fundamental wave echo signals synthesized according to the multiple groups of wave beams are sent to a signal processing module for relevant signal processing. The fundamental wave echo signals processed by the signal processing module are sent to an image processing module (such as an image processing unit (GPU)), the fundamental wave echo signals are processed by the image processing module to form a plurality of groups of sub-ultrasonic images of at least one part of a scanning target, and the sub-ultrasonic images of one frame are correspondingly obtained by the first ultrasonic wave transmitted each time.

In step a4, the multiple sets of sub-ultrasound images are superimposed to obtain a first ultrasound image.

For multiple groups of sub-ultrasonic images obtained by emitting the first ultrasonic waves at different deflection angles, coherent superposition can be carried out to obtain the first ultrasonic image, which is equivalent to coherent enhancement between the ultrasonic plane waves emitted from multiple angles, and an effect similar to focusing is generated, so that the enhancement of image resolution and contrast is realized.

A specific definition of coherent superposition may refer to images formed by superimposing data beamformed using, for example, plane waves according to different deflection angles without performing an envelope or other non-linear process. The coherent superposition may be performed by any suitable method, for example, in the synthesis of calculating the multi-angle plane wave, a linear coordinate system may be established first, and the delay time of the pixel may be calculated by using the coordinate values of the pixel and the coordinate values of the array element in the linear coordinate system, so as to calculate the image of coherent superposition.

In another embodiment, in step a1, the first ultrasound echo signals may be first beamformed to obtain multiple sets of beamformed first ultrasound echo signals. In step a2, fundamental wave components are extracted from the first ultrasonic echo signals that are beamformed, respectively, to obtain beamformed fundamental wave echo signals. Compared with the implementation mode of firstly performing beam forming and then extracting components, the method of firstly extracting components and then performing beam forming, which is described in detail above, can well reduce the operation amount of the beam forming link, and is more beneficial to performing rapid imaging.

With continued reference to fig. 7, in step S706, harmonic components of the multiple sets of second ultrasound echo signals are acquired, and a second ultrasound image of at least a portion of the scan target is obtained according to the harmonic components. In this context, the ultrasound image may be a B-map, color image, or the like.

The harmonic component may be extracted by any suitable method, such as by bandwidth limited filtering to remove the fundamental signal (e.g., by a fundamental filter) and harmonic components more than 3 times, and extracting harmonic components 2 from the echo signal.

The method of obtaining the second ultrasound image of at least a portion of the scan target from the harmonic component may use any suitable method currently and generally used in the art in the future, and is not particularly limited herein.

With continued reference to fig. 7, in step S707, a target ultrasound image of one frame of at least a part of the scan target is obtained according to the first ultrasound image and the second ultrasound image, and since the first ultrasound image is an image of the imaging region based on the fundamental component and the second ultrasound image is an image of the imaging region based on the harmonic component, the high contrast resolution of the harmonic and the high penetration force of the fundamental wave are both considered, and the quality of the obtained target ultrasound image is high.

The first ultrasound image and the second ultrasound image are composited according to different imaging modes required by a user by using an image processing module 8 (such as an image processing unit (GPU)), for example, to obtain a target ultrasound image of one frame.

The first and second ultrasound images may be compounded using any suitable method currently and generally used in the art in the future and will not be described in detail herein.

Optionally, the length of the scan sequence for scanning the target based on the first ultrasonic wave and the focused ultrasonic wave is a sum of the first order and the second order. Taking the case of transmitting plane waves at M different deflection angles as an example, as shown in fig. 6, compared with the conventional frequency composite scanning sequence shown in fig. 2, the scanning sequence of the method according to the embodiment of the present invention is N times as many as the transmission times of focused ultrasonic waves for extracting harmonic components (i.e., harmonic frequencies), whereas the method proposed by the present invention performs fundamental wave imaging by using first ultrasonic waves (e.g., plane waves, divergent waves, or wide-beam ultrasonic waves), which transmit plane waves at M different angles in total, the total number of fundamental wave frequency transmissions is M, and the number of fundamental wave frequency transmissions is N in the conventional method. The number of plane wave transmissions M is much smaller than N (typically M is about ten times, N is several tens to hundreds) for equivalent image quality. Obviously, the sequence length (M + N) of the scanning method of the embodiment of the present invention is significantly smaller than the sequence length (2N) of the conventional scanning method, so that under the condition of the same image quality, the method of the embodiment of the present invention can effectively reduce the number of times of transmitting ultrasonic waves for obtaining a frame of target ultrasonic image, and improve the imaging frame rate, thereby improving the time resolution of ultrasonic imaging (for example, two-dimensional images or three-dimensional images), and enabling the system to have better dynamic characteristics.

It should be noted that the order of the steps of the method shown in fig. 7 may also be changed as appropriate, for example, step S705 may also be placed after step S702 and before step S703, or step S705 may also be placed after step S704 and before step S705. At least some of the steps in fig. 7 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, in different orders, and may be performed alternately or at least partially with respect to other steps or sub-steps or stages of other steps.

Based on the foregoing ultrasound imaging method, an embodiment of the present invention further provides an ultrasound imaging system, as shown in fig. 1, including:

a probe 1;

a transmitting circuit 2, configured to excite the probe 1 to transmit a first ultrasonic wave for a first number of times to the scan target and transmit a second number of focused ultrasonic waves to the scan target, where an area of an imaging region of the scan target covered by each transmitted first ultrasonic wave is larger than an area of an imaging region of the scan target covered by each transmitted focused ultrasonic wave;

the receiving circuit 4 and the beam forming module 5 are configured to receive echoes of the first ultrasonic waves transmitted each time, respectively, obtain one or more groups of first ultrasonic echo signals, obtain fundamental wave components of the first ultrasonic echo signals based on the first ultrasonic echo signals, receive echoes of the focused ultrasonic waves transmitted each time, obtain multiple groups of second ultrasonic echo signals, and obtain harmonic components of the second ultrasonic echo signals based on the second ultrasonic echo signals;

a processor 6 for: obtaining a first ultrasonic image of at least one part of the scanning target according to the fundamental wave component of the one or more groups of first ultrasonic echo signals, obtaining a second ultrasonic image of at least one part of the scanning target according to the harmonic component of the groups of second ultrasonic echo signals, and obtaining a target ultrasonic image of one frame of at least one part of the scanning target according to the first ultrasonic image and the second ultrasonic image.

In one example, the ultrasound imaging system further includes a Display (not shown) for displaying information input by or provided to the user and various graphical user interfaces of the ultrasound imaging apparatus, which may be composed of graphics, text, icons, video, and any combination thereof, in this embodiment, the Display may Display the target ultrasound image, and the Display may include a Display panel, and optionally, the Display panel may be configured in the form of a Liquid Crystal Display (LCD), an Organic Light-Emitting Diode (OLED), or the like.

In one example, the ultrasound imaging system further includes a storage device (not shown), which may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and/or non-volatile memory. The volatile memory may include, for example, Random Access Memory (RAM), cache memory (cache), and/or the like. The non-volatile memory may include, for example, Read Only Memory (ROM), hard disk, flash memory, etc. On which one or more computer program instructions may be stored that may be executed by processor 6 to implement the functions of the embodiments of the invention described herein (as implemented by the processor) and/or other desired functions. Various applications and various data, such as various data used and/or generated by the applications, may also be stored in the computer-readable storage medium.

In one example, the ultrasound imaging system further includes an input device (not shown) which may be a device used by a user to input instructions and may include one or more of a keyboard, mouse, microphone, touch screen, and the like.

In one embodiment of the invention, the first ultrasonic wave comprises a non-focused ultrasonic wave or a broad beam ultrasonic wave, wherein the non-focused ultrasonic wave comprises at least one of a plane wave and a divergent wave.

In one embodiment of the invention, the first ultrasonic waves comprise unfocused ultrasonic waves; wherein each emitted unfocused ultrasonic wave covers the entire imaging area of the scan target, or each emitted unfocused ultrasonic wave covers a partial area of the entire imaging area of the scan target, and the emitted focused ultrasonic waves of the second number cover the entire imaging area of the scan target.

In one embodiment of the invention, the transmission circuit 2 is also used to excite the probe 1:

continuously transmitting first ultrasonic waves to a scanning target until the transmitting times of the first ultrasonic waves reach a first time number, and continuously transmitting focused ultrasonic waves to the scanning target until the transmitting times of the focused ultrasonic waves reach a second time number; or

Continuously transmitting focused ultrasonic waves to a scanning target until the transmitting times of the focused ultrasonic waves reach a second time, and continuously transmitting first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach a first time; or

And transmitting the focused ultrasonic waves of partial times in the second time to the scanning target, continuously transmitting the first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach the first time, and finally transmitting the focused ultrasonic waves of the rest times in the second time to the scanning target.

In one embodiment of the invention, the transmit circuit 2 is also arranged to excite the probe 1, when there is no overlapping scan area between the first ultrasound waves transmitted each time: the first ultrasonic wave and the focused ultrasonic wave are alternately transmitted to the scan target until the number of transmissions of the first ultrasonic wave reaches the first number and the number of transmissions of the focused ultrasonic wave reaches the second number.

In one embodiment of the invention, the transmit circuit 2 is also arranged to excite the probe 1, when there is no overlapping scan area between the first ultrasound waves transmitted each time: and transmitting the focused ultrasonic wave to the scanning target at least once after transmitting the first ultrasonic wave to the scanning target at least once, or transmitting the first ultrasonic wave to the scanning target at least once after transmitting the focused ultrasonic wave to the scanning target at least once.

In one embodiment of the present invention, the first ultrasonic waves emitted to the scan target a first number of times cover the entire imaging area, wherein each time the first ultrasonic waves emitted to the scan target cover a partial area of the entire imaging area, there is no overlap between the partial areas; or the first ultrasonic wave emitted to the scanning target covers partial areas of the whole imaging area at each time, and the partial areas are partially overlapped.

In one embodiment of the present invention, when the partial regions are partially overlapped, the transmitting circuit 2 is configured to excite the probe 1 to continuously transmit the first ultrasonic wave to the scanning target until the number of transmissions reaches the first number; or, when there is no overlap between the partial regions, the transmitting circuit is configured to excite the probe to continuously transmit the first ultrasonic wave to the scan target until the number of transmissions reaches the first number, or, the transmitting circuit is configured to excite the probe to alternately transmit the first ultrasonic wave and the focused ultrasonic wave to the scan target.

In one embodiment of the invention, unfocused ultrasound waves are transmitted to the scan target a plurality of times, and at least two of the unfocused ultrasound waves transmitted have different deflection angles.

In one embodiment of the present invention, the receiving circuit 4 is configured to extract fundamental components from the plurality of sets of first ultrasonic echo signals, respectively; the beam forming module 5 is configured to: performing beam synthesis on the extracted fundamental wave components to obtain a plurality of groups of beam-synthesized fundamental wave echo signals; the processor 6 is configured to: respectively obtaining a plurality of groups of sub ultrasonic images of at least one part of the scanning target according to the fundamental wave echo signals synthesized by a plurality of groups of wave beams; and overlapping the multiple groups of sub-ultrasonic images to obtain the first ultrasonic image.

In one embodiment of the invention, the first number of times is less than the second number of times, wherein the first number of times is 1/100 to 3/4 of the second number of times.

In one embodiment of the present invention, a length of a scan sequence of the scan target based on the first ultrasonic wave and the focused ultrasonic wave is a sum of the first number of times and the second number of times.

In one embodiment of the present invention, when the probe is a linear array probe and the first ultrasonic wave transmitted is a non-focused ultrasonic wave, the non-focused ultrasonic wave is a plane wave, and when the probe is a convex array or a phased array probe and the first ultrasonic wave transmitted is a non-focused ultrasonic wave, the non-focused ultrasonic wave is a diverging wave.

In addition, the embodiment of the invention also provides a computer storage medium, and the computer storage medium is stored with the computer program. One or more computer program instructions may be stored on the computer-readable storage medium, which may be executed by a processor to implement the program instructions stored by the storage device to implement the functions of the embodiments of the invention (implemented by the processor) described herein and/or other desired functions, such as performing the corresponding steps of the ultrasound imaging method according to the embodiments of the invention, and various applications and various data, such as various data used and/or generated by the applications, etc., may also be stored in the computer-readable storage medium.

For example, 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.

In summary, the method and system of the embodiments of the present invention provide a new frequency compound scanning method, which extracts harmonic components (also called harmonic signals) by using focused ultrasound scanning (because harmonic signals require higher energy to be excited, harmonic frequencies are scanned by using high energy of focused ultrasound), extracts fundamental components (also called fundamental signals) by using ultrasound scanning of, for example, plane waves, and then compounds the two to obtain the final ultrasound image of the display target. Compared with the traditional focused wave fundamental wave imaging, the fundamental wave imaging of the plane waves can greatly reduce the emission times of one-frame scanning, thereby improving the scanning frame rate, improving the time resolution and ensuring that the system has better dynamic characteristics.

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 functionality of some of the modules 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 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.

Claims

1. An ultrasound imaging method, comprising:

transmitting a first number of first ultrasonic waves to a scanning target;

2. The ultrasonic imaging method of claim 1, wherein the first ultrasonic wave comprises a non-focused ultrasonic wave or a broad beam ultrasonic wave, wherein the non-focused ultrasonic wave comprises at least one of a plane wave and a diverging wave.

3. The ultrasonic imaging method of claim 1, wherein the first ultrasonic waves comprise unfocused ultrasonic waves; wherein the unfocused ultrasound waves of each transmission cover the entire imaging area of the scan target, and/or the focused ultrasound waves of the second number of transmissions cover the entire imaging area of the scan target.

4. The ultrasonic imaging method according to any one of claims 1 to 3,

continuously transmitting the first ultrasonic wave to the scanning target until the transmitting times of the first ultrasonic wave reach the first times, and then continuously transmitting the focused ultrasonic wave to the scanning target until the transmitting times of the focused ultrasonic wave reach the second times; or

Continuously transmitting the focused ultrasonic waves to the scanning target until the transmitting times of the focused ultrasonic waves reach the second times, and then continuously transmitting the first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach the first times; or

And transmitting the focused ultrasonic waves of partial times in the second times to the scanning target, continuously transmitting the first ultrasonic waves to the scanning target until the transmitting times of the first ultrasonic waves reach the first times, and finally transmitting the focused ultrasonic waves of the rest times in the second times to the scanning target.

5. An ultrasonic imaging method according to any one of claims 1 to 3, wherein the first ultrasonic wave and the focused ultrasonic wave are alternately transmitted to the scan target until the number of transmissions of the first ultrasonic wave reaches the first number and the number of transmissions of the focused ultrasonic wave reaches the second number.

6. An ultrasound imaging method according to claim 5, wherein the focused ultrasound wave is transmitted to the scan target at least once again after the first ultrasound wave is transmitted at least once to the scan target, or at least once again after the focused ultrasound wave is transmitted at least once to the scan target.

7. The ultrasonic imaging method of claim 1, wherein transmitting a first number of first ultrasonic waves to a scan target comprises: transmitting a first ultrasonic wave to the scan target a plurality of times, and at least two of the transmitted first ultrasonic waves have different deflection angles.

8. The ultrasonic imaging method according to claim 7, wherein acquiring a fundamental component of the plurality of sets of the first ultrasonic echo signals, from which a first ultrasonic image of at least a part of the scan target is obtained, includes:

extracting fundamental wave components from the plurality of sets of first ultrasonic echo signals, respectively;

performing beam synthesis on the extracted fundamental wave components to obtain a plurality of groups of beam-synthesized fundamental wave echo signals;

respectively obtaining a plurality of groups of sub ultrasonic images of at least one part of the scanning target according to the fundamental wave echo signals synthesized by a plurality of groups of wave beams; and

superposing the multiple groups of sub-ultrasonic images to obtain the first ultrasonic image;

or,

respectively carrying out beam synthesis on the multiple groups of first ultrasonic echo signals to obtain multiple groups of beam synthesized first echo signals;

extracting fundamental wave components from the first echo signals synthesized by the multiple groups of wave beams respectively to obtain multiple groups of wave beam synthesized fundamental wave echo signals;

and overlapping the multiple groups of sub-ultrasonic images to obtain the first ultrasonic image.

9. The ultrasonic imaging method according to claim 1 or 2, wherein the first ultrasonic wave of the first number of times transmitted to the scan target covers the entire imaging area, wherein,

the first ultrasonic waves emitted to the scanning target each time cover partial areas of the whole imaging area, and the partial areas are not overlapped; or

The first ultrasonic waves emitted to the scanning target each time cover partial areas of the whole imaging area, and the partial areas are partially overlapped.

10. The ultrasonic imaging method according to claim 9, wherein when the partial regions are partially overlapped with each other, the first ultrasonic wave is continuously emitted to the scan target until the number of emissions reaches the first number;

when there is no overlap between the partial regions, the first ultrasonic wave is continuously transmitted to the scan target until the number of transmissions reaches the first number, or the first ultrasonic wave and the focused ultrasonic wave are alternately transmitted to the scan target.

11. The ultrasound imaging method of claim 1, wherein the first number of times is less than the second number of times, wherein the first number of times is 1/100 through 3/4 of the second number of times.

12. An ultrasound imaging method according to claim 1, wherein a length of a scan sequence of the scan target based on the first ultrasonic wave and the focused ultrasonic wave is a sum of the first number and the second number.

13. An ultrasound imaging method, comprising:

transmitting a first ultrasonic wave to a scanning target, and acquiring a first ultrasonic echo signal according to an echo of the transmitted first ultrasonic wave;

transmitting focused ultrasonic waves to a scanning target, and acquiring a second ultrasonic echo signal according to the echoes of the transmitted focused ultrasonic waves; wherein the area of the imaging region of the scan target covered by the single shot of the first ultrasonic wave is larger than the area of the imaging region of the scan target covered by the single shot of the focused ultrasonic wave;

acquiring a fundamental component of the first ultrasonic echo signal, and acquiring a first ultrasonic image of an imaging region of the scanning target according to the fundamental component;

obtaining a harmonic component of the second ultrasonic echo signal, and obtaining a second ultrasonic image of an imaging region of the scanning target according to the harmonic component; and

obtaining a target ultrasound image of one frame of an imaging region of the scan target from the first ultrasound image and the second ultrasound image.

14. The ultrasonic imaging method of claim 13, wherein the first ultrasonic wave comprises a non-focused ultrasonic wave or a broad beam ultrasonic wave; wherein:

the first ultrasonic wave emitted each time covers the whole imaging area of the scanning target, and the second focused ultrasonic wave emitted each time covers the whole imaging area of the scanning target;

or, the first ultrasonic wave emitted each time covers a partial area of the whole imaging area of the scanning target, the first ultrasonic wave emitted for the first times covers the whole imaging area of the scanning target, and the focused ultrasonic wave emitted for the second times covers the whole imaging area of the scanning target;

alternatively, the first ultrasonic wave of the first number of times of transmission and the focused ultrasonic wave of the second number of times of transmission cover the same area of the entire imaging area of the scan target.

15. An ultrasound imaging system, comprising:

a probe;

the receiving circuit and the beam synthesis module are used for respectively obtaining a first ultrasonic echo signal based on the echo of the first ultrasonic wave received from each emission and obtaining a fundamental wave component thereof based on the first ultrasonic echo signal, and respectively obtaining a second ultrasonic echo signal based on the echo of the focused ultrasonic wave received from each emission and obtaining a harmonic wave component thereof based on the second ultrasonic echo signal;

a processor to:

obtaining a first ultrasound image of at least a portion of the scan target from a fundamental component of the first ultrasound echo signal,

obtaining a second ultrasound image of at least a portion of the scan target from harmonic components of the second ultrasound echo signal,

16. The ultrasound imaging system of claim 15, wherein the first ultrasound waves comprise unfocused ultrasound waves comprising at least one of plane waves and diverging waves; wherein the unfocused ultrasound waves of each transmission cover the entire imaging area of the scan target, and/or the focused ultrasound waves of the second number of transmissions cover the entire imaging area of the scan target.

17. The ultrasound imaging system of claim 15 or 16, wherein the transmit circuitry is to excite the probe to:

18. The ultrasound imaging system of claim 15, wherein the transmit circuitry to excite the probe to transmit a first number of first ultrasound waves to a scan target comprises: the first ultrasonic wave is transmitted to the scanning target for a plurality of times, and the first ultrasonic wave transmitted for at least two times has different deflection angles.

19. The ultrasound imaging system of claim 18, wherein the receive circuitry is to: extracting fundamental wave components from the first ultrasonic echo signals, respectively; the beam forming module is configured to: performing beam forming on the extracted fundamental wave component to obtain a beam-formed fundamental wave echo signal;

the processor is configured to:

respectively obtaining a plurality of groups of sub ultrasonic images of at least one part of the scanning target according to the wave beam synthesized fundamental echo signals; and

20. The ultrasound imaging system of claim 15, wherein the first ultrasound waves comprise unfocused ultrasound waves or broad beam ultrasound waves; the first ultrasonic wave of a first time is transmitted to the scanning target to cover the whole imaging area, wherein each time the first ultrasonic wave transmitted to the scanning target covers partial areas of the whole imaging area, the partial areas are partially overlapped, and the transmitting circuit is used for exciting the probe to continuously transmit the first ultrasonic wave to the scanning target until the transmitting time reaches the first time.

21. The ultrasound imaging system of claim 15, wherein the first number of times is less than the second number of times, wherein the first number of times is 1/100 through 3/4 of the second number of times; and/or the length of a scanning sequence of the scanning target based on the first ultrasonic wave and the focused ultrasonic wave is the sum of the first times and the second times.

22. The ultrasonic imaging system of claim 15, 16 or 20, wherein the probe is a linear array probe and the first ultrasonic wave transmitted is a non-focused ultrasonic wave, the non-focused ultrasonic wave is a plane wave, and when the probe is a convex array or a phased array probe and the first ultrasonic wave transmitted is a non-focused ultrasonic wave, the non-focused ultrasonic wave is a diverging wave.