An ultrasound imaging method and device

Abstract

An ultrasound imaging method and apparatus are disclosed. The method includes: controlling an ultrasound probe to emit ultrasound waves toward a target tissue, receiving echo signals from the ultrasound waves, and generating an ultrasound image of the target tissue in real time based on the echo signals; a processor obtaining a velocity index reflecting the movement speed of the ultrasound probe during the emission of ultrasound waves toward the target tissue; the processor adjusting the imaging frame rate of the ultrasound probe according to the velocity index, wherein a higher velocity index indicates a higher imaging frame rate; and the processor adjusting the transmission power of the ultrasound probe according to the imaging frame rate, wherein a higher imaging frame rate corresponds to a lower transmission power. This invention adjusts the imaging frame rate based on the ultrasound probe's velocity index and the transmission power based on the imaging frame rate, thereby using a higher frame rate to ensure imaging speed during the search for cross-sections and using higher transmission power to ensure imaging quality during cross-section observation.

Description

Technical Field

[0001] This invention relates to the field of ultrasound imaging technology, and more specifically to an ultrasound imaging method and an ultrasound imaging system. Background Technology

[0002] Ultrasound imaging, as the most widely used examination method in modern medical imaging technology, is widely applied in disease diagnosis due to its advantages such as low cost, rapid imaging, and high reliability. However, in the examination of some sensitive tissues (such as early pregnancy fetuses, fetal eyes, and adult eyes), if the energy of ultrasound transmitted to the sensitive tissue is high enough, it can cause cavitation of the tissue and / or fluid, thereby causing tissue damage. Therefore, when using ultrasound to examine particularly sensitive tissues, it is necessary to strictly control the acoustic power.

[0003] Existing ultrasound imaging systems do not adequately meet the requirements for use on sensitive tissues, and it is difficult to achieve a balance between transmission power and image quality. For example, if low transmission power is used, corresponding to a low mechanical index, it meets the requirements for examining sensitive tissues, but the ultrasound image quality is poor and cannot meet diagnostic requirements. On the other hand, if high transmission power is used, corresponding to a high mechanical index, the ultrasound image can meet diagnostic requirements, but the acoustic power does not meet the safety requirements for sensitive tissues such as the eyes, early pregnancy fetuses, and fetal eyes. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] A first aspect of this invention provides an ultrasound imaging method for an ultrasound imaging system, the ultrasound imaging system including an ultrasound probe, a transmitting circuit, a receiving circuit, and a processor, the method comprising:

[0006] The processor controls the ultrasound probe to emit ultrasound waves toward the target tissue, receives the echo signals of the ultrasound waves, and generates an ultrasound image of the target tissue in real time based on the echo signals of the ultrasound waves.

[0007] During the process of controlling the ultrasonic probe to emit ultrasonic waves toward the target tissue, the processor obtains a speed index reflecting the movement speed of the ultrasonic probe.

[0008] The processor adjusts the imaging frame rate of the ultrasound probe according to the speed index, wherein the speed index reflects that the faster the ultrasound probe moves, the higher the imaging frame rate.

[0009] The processor acquires a pre-set correspondence between imaging frame rate and transmission power, and adjusts the transmission power of the ultrasound probe according to the imaging frame rate and the correspondence, wherein the higher the imaging frame rate, the lower the transmission power.

[0010] In some embodiments, obtaining the velocity index reflecting the motion velocity of the ultrasonic probe includes:

[0011] A velocity index reflecting the movement speed of the ultrasound probe is obtained based on the changes between the current frame ultrasound image and its neighboring frames ultrasound images.

[0012] In some embodiments, obtaining a velocity index reflecting the motion speed of the ultrasound probe based on the change between the current frame ultrasound image and its neighboring frame ultrasound images includes:

[0013] Determine the pixel differences between at least a portion of the pixels in the current frame ultrasound image and the neighboring frame ultrasound images;

[0014] The pixel differences of at least some of the pixels are accumulated to obtain an accumulated pixel difference, and the speed index is determined based on the accumulated pixel difference.

[0015] In some embodiments, obtaining a velocity index reflecting the motion velocity of the ultrasound probe based on the change between the current frame ultrasound image and its neighboring frame ultrasound images includes:

[0016] The similarity between the current frame ultrasound image and the neighboring frame ultrasound images is calculated according to a preset similarity algorithm, and the speed index is determined based on the similarity.

[0017] In some embodiments, adjusting the imaging frame rate of the ultrasound imaging according to the velocity index includes:

[0018] The imaging frame rate is adjusted according to the functional relationship between the imaging frame rate and the speed index, so that the imaging frame rate changes dynamically with the speed index.

[0019] In some embodiments, the method further includes: when the speed index is higher than a first speed index, maintaining the imaging frame rate at a first imaging frame rate corresponding to the first speed index.

[0020] In some embodiments, adjusting the imaging frame rate of the ultrasound imaging according to the velocity index includes:

[0021] Determine the threshold range in which the speed index falls, and adjust the imaging frame rate to the imaging frame rate corresponding to the threshold range.

[0022] In some embodiments, determining the threshold range in which the velocity index falls and adjusting the imaging frame rate to an imaging frame rate corresponding to the threshold range includes:

[0023] During ultrasound imaging of the target tissue using a first imaging frame rate, if the speed index is detected to be lower than a second speed index, the imaging frame rate is adjusted from the first imaging frame rate to the second imaging frame rate, where the second imaging frame rate is lower than the first imaging frame rate.

[0024] In some embodiments, adjusting the imaging frame rate of the ultrasound imaging according to the velocity index includes:

[0025] The imaging frame rate of the ultrasound imaging is adjusted by adjusting the time interval between two adjacent transmissions of the ultrasound probe and / or adjusting the time interval between two adjacent ultrasound images.

[0026] In some embodiments, the correspondence between the imaging frame rate and the transmission power includes the correspondence between the imaging frame rate adjustment range and the transmission power adjustment range;

[0027] The step of adjusting the transmission power of the ultrasound probe according to the imaging frame rate and the corresponding relationship includes:

[0028] The adjustment range of the imaging frame rate is determined based on the imaging frame rate before and after adjustment.

[0029] The transmission power adjustment range is determined based on the correspondence between the imaging frame rate adjustment range and the transmission power adjustment range, wherein the larger the imaging frame rate adjustment range, the larger the transmission power adjustment range.

[0030] The transmission power is adjusted according to the transmission power adjustment range.

[0031] In some embodiments, adjusting the transmission power of the ultrasound probe according to the imaging frame rate includes:

[0032] When the imaging frame rate is adjusted from the first imaging frame rate to the second imaging frame rate, the transmission power is adjusted from the first transmission power corresponding to the first imaging frame rate to the second transmission power corresponding to the second imaging frame rate, according to the correspondence between the imaging frame rate and the transmission power.

[0033] Another aspect of the present invention provides an ultrasound imaging system, the ultrasound imaging system comprising:

[0034] Ultrasonic probe;

[0035] A transmitting circuit is used to excite the ultrasound probe to emit ultrasound waves toward the target tissue.

[0036] A receiving circuit is used to control the ultrasonic probe to receive the echo of the ultrasonic wave in order to obtain the echo signal of the ultrasonic wave.

[0037] A processor for performing the steps of the ultrasound imaging method as described above;

[0038] A display for showing the ultrasound images generated by the processor.

[0039] According to the embodiments of the present invention, the ultrasound imaging method and ultrasound imaging system adjust the imaging frame rate according to the speed index of the ultrasound probe and adjust the transmission power of the ultrasound probe according to the imaging frame rate, thereby using a higher frame rate to ensure imaging speed during the process of finding the cross-section and using a higher transmission power to ensure imaging quality during the process of observing the cross-section, while using a lower imaging frame rate to avoid excessive temperature rise, thereby ensuring tissue safety. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] In the attached diagram:

[0042] Figure 1 A schematic block diagram of an ultrasound imaging system according to an embodiment of the present invention is shown;

[0043] Figure 2 A schematic flowchart of an ultrasound imaging method according to an embodiment of the present invention is shown;

[0044] Figure 3 A schematic diagram illustrating the adjustment of the imaging frame rate according to an embodiment of the present invention is shown. Detailed Implementation

[0045] To make the objectives, 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. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of the present invention.

[0046] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0047] It should be understood that the invention can be embodied in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0048] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0049] To fully understand this invention, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this invention. Optional embodiments of the invention are described in detail below; however, in addition to these detailed descriptions, the invention may have other embodiments.

[0050] Below, first refer to Figure 1 An ultrasound imaging system according to an embodiment of the present invention is described. Figure 1 A schematic structural block diagram of an ultrasound imaging system 100 according to an embodiment of the present invention is shown.

[0051] like Figure 1 As shown, the ultrasound imaging system 100 includes an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118. Further, the ultrasound imaging system may also include a transmit / receive selection switch 120 and a beamforming module 122. The transmitting circuit 112 and the receiving circuit 114 can be connected to the ultrasound probe 110 via the transmit / receive selection switch 120.

[0052] The ultrasonic probe 110 includes multiple transducer elements. These elements can be arranged in a row to form a linear array, or in a two-dimensional matrix to form a planar array. They can also form a convex array. Each transducer element is used to emit ultrasonic waves based on an excitation electrical signal, or to convert received ultrasonic waves into electrical signals. Therefore, each transducer element can be used to achieve the mutual conversion between electrical pulse signals and ultrasonic waves, thereby enabling the emission of ultrasonic waves to the target area of ​​the object being tested, and also to receive ultrasonic wave echoes reflected back from the tissue. During ultrasonic testing, the transmission and reception sequences can be used to control which transducer elements are used to emit ultrasonic waves and which are used to receive ultrasonic waves, or to control the transducer elements to be used in time-slotted manner for emitting ultrasonic waves or receiving ultrasonic wave echoes. Transducer elements participating in ultrasonic wave emission can be simultaneously excited by electrical signals, thus emitting ultrasonic waves simultaneously; alternatively, transducer elements participating in ultrasonic beam emission can be excited by several electrical signals with a certain time interval, thus continuously emitting ultrasonic waves with a certain time interval.

[0053] During ultrasound imaging, the transmitting circuit 112 sends a delayed-focused transmission pulse to the ultrasound probe 110 via the transmit / receive selection switch 120. Excited by the transmission pulse, the ultrasound probe 110 emits an ultrasonic beam towards the tissue of the target area of ​​the object being measured. After a certain delay, it receives the ultrasonic echo reflecting back from the tissue of the target area, carrying tissue information, and converts this ultrasonic echo back into an electrical signal. The receiving circuit 114 receives the electrical signal converted by the ultrasound probe 110, obtains the ultrasonic echo signal, and sends these ultrasonic echo signals to the beamforming module 122. The beamforming module 122 performs focusing delay, weighting, and channel summation on the ultrasonic echo data, and then sends it to the processor 116. The processor 116 performs signal detection, signal enhancement, data conversion, and logarithmic compression on the ultrasonic echo signal to form an ultrasound image. The ultrasound image obtained by the processor 116 can be displayed on the display 118 or stored in the memory 124.

[0054] Optionally, the processor 116 can be implemented as software, hardware, firmware, or any combination thereof, and can use one or more application-specific integrated circuits (ASICs), one or more general-purpose integrated circuits, one or more microprocessors, one or more programmable logic devices, or any combination of the foregoing circuits and / or devices, or other suitable circuits or devices. Furthermore, the processor 116 can control other components in the ultrasound imaging system 100 to perform the corresponding steps of the methods in the various embodiments of this specification.

[0055] The display 118 is connected to the processor 116. The display 118 can be a touch screen, an LCD screen, etc.; or, the display 118 can be an independent display such as an LCD screen or a television, separate from the ultrasound imaging system 100; or, the display 118 can be the screen of an electronic device such as a smartphone or tablet, etc. The number of displays 118 can be one or more.

[0056] The display 118 can display the ultrasound images obtained by the processor 116. Furthermore, while displaying the ultrasound images, the display 118 can also provide a graphical user interface for human-machine interaction. One or more controlled objects can be set on the graphical interface, allowing the user to input operation commands using a human-machine interaction device to control these controlled objects and perform corresponding control operations. For example, icons can be displayed on the graphical interface, and the human-machine interaction device can be used to operate these icons to perform specific functions, such as drawing a region of interest bounding box on the ultrasound image.

[0057] Optionally, the ultrasound imaging system 100 may also include other human-machine interface devices besides the display 118, which are connected to the processor 116. For example, the processor 116 may be connected to the human-machine interface device via an external input / output port, which may be a wireless communication module, a wired communication module, or a combination of both. The external input / output port may also be based on USB, bus protocols such as CAN, and / or wired network protocols.

[0058] The human-computer interaction device may include an input device for detecting user input information. This input information may be, for example, control commands for the timing of ultrasound transmission / reception, operational input commands for drawing points, lines, or boxes on an ultrasound image, or other types of commands. The input device may include one or a combination of several of the following: a keyboard, mouse, scroll wheel, trackball, mobile input device (e.g., a mobile device with a touchscreen, a mobile phone, etc.), a multi-function knob, etc. The human-computer interaction device may also include an output device such as a printer.

[0059] The ultrasound imaging system 100 may also include a memory 124 for storing instructions executed by the processor, storing received ultrasound echoes, storing ultrasound images, etc. The memory may be a flash memory card, solid-state memory, hard disk, etc. It may be volatile and / or non-volatile memory, removable memory and / or non-removable memory, etc.

[0060] It should be understood that Figure 1 The components included in the ultrasound imaging system 100 shown are merely illustrative and may include more or fewer components. This invention is not limited thereto.

[0061] The following reference Figure 2 The ultrasound imaging method proposed in the embodiments of the present invention is described below. Figure 2 This is a schematic flowchart of an ultrasound imaging method 200 according to an embodiment of the present invention. Specifically, the ultrasound imaging method 200 according to an embodiment of the present invention includes the following steps:

[0062] In step S210, the processor controls the ultrasound probe to emit ultrasound waves toward the target tissue, receives the echo signal of the ultrasound waves, and generates an ultrasound image of the target tissue in real time based on the echo signal of the ultrasound waves.

[0063] In step S220, the processor obtains a speed index reflecting the movement speed of the ultrasound probe while controlling the ultrasound probe to emit ultrasound waves toward the target tissue.

[0064] In step S230, the processor adjusts the imaging frame rate of the ultrasound probe according to the speed index, wherein the speed index reflects that the faster the ultrasound probe moves, the higher the imaging frame rate.

[0065] In step S240, the processor obtains a preset correspondence between imaging frame rate and transmission power, and adjusts the transmission power of the ultrasound probe according to the imaging frame rate and the correspondence, wherein the higher the imaging frame rate, the lower the transmission power.

[0066] The ultrasound imaging method 200 of this invention adjusts the imaging frame rate according to the speed index of the ultrasound probe and adjusts the transmission power of the ultrasound probe according to the imaging frame rate. This allows for the use of a higher frame rate during the search for the cross-section to ensure imaging speed, and a higher transmission power during the observation of the cross-section to ensure imaging quality. At the same time, a lower imaging frame rate is used to avoid excessive temperature rise, thereby ensuring tissue safety. Ultimately, this solves the problem of balancing safety requirements and image quality during ultrasound examinations of sensitive tissues such as the eyes and early-pregnancy fetuses.

[0067] Ultrasonic power primarily comprises four parameters: mechanical index (MI), thermal index (TI), acoustic intensity, and temperature rise. The mechanical index is instantaneous and does not accumulate with scan time, while the thermal index (TI), acoustic intensity, and temperature rise are cumulative and increase with scan time. These parameters also interact; for example, within the same time frame, increasing the mechanical index will result in a greater temperature rise compared to not increasing it. Once any one of these four parameters reaches its limit, the others cannot be further increased.

[0068] Practice shows that among the four indicators mentioned above, temperature rise is the most likely to exceed the limit. When temperature rise exceeds the limit, the mechanical index has generally not yet reached the limit standard and there is still room for improvement. However, since increasing the mechanical index will lead to further temperature rise exceeding the limit, the mechanical index cannot be directly increased at this time. The mechanical index directly affects the image quality of ultrasound images. Therefore, the embodiments of this invention aim to improve the mechanical index while avoiding excessive temperature rise.

[0069] During ultrasound examinations, a higher frame rate results in shorter time intervals between adjacent frames, leading to a smoother ultrasound scan. However, this also means the tissue receives more ultrasound waves within the same timeframe, causing a faster temperature rise. Conversely, a lower frame rate results in longer time intervals between adjacent frames, with fewer ultrasound waves received by the tissue within the same timeframe, leading to a slower temperature rise. Therefore, reducing the frame rate decreases the total number of transmissions within a given time, reducing temperature rise and making it less likely to reach the temperature limit. This allows for increasing the transmission power of the ultrasound probe to improve mechanical properties and thus image quality. However, since ultrasound examinations require a certain temporal resolution, directly reducing the frame rate without considering the usage scenario will negatively impact examination results, causing untimely ultrasound image updates and affecting the user experience.

[0070] In fact, a high frame rate is not always necessary during ultrasound examinations. The examination process can be broadly divided into two types: one is the process of locating the section, where the user moves the ultrasound probe rapidly, resulting in drastic changes between adjacent frames. In this case, a higher frame rate is needed to ensure timely image updates and facilitate section localization. The other type is the process of observing the section, where the user has already located the section and is only observing the tissue structure under examination within a small area. In this case, changes between adjacent frames are minimal, and a lower frame rate will hardly affect the user's observation of the section. Therefore, the frame rate can be appropriately reduced to minimize temperature rise.

[0071] Therefore, in order to improve mechanical properties while avoiding excessive temperature rise, the strategy adopted in this embodiment of the invention is to reduce the frame rate when the ultrasonic probe is detected to be moving too fast, and to increase the transmission power of the ultrasonic probe while reducing the frame rate. If the ultrasonic probe is moving too fast, it indicates that the user is looking for a cross-section, and a higher frame rate is used to ensure smooth display of the ultrasonic image; if the ultrasonic probe is moving too slowly, it indicates that the user has already located the cross-section, and a lower frame rate is used while increasing the transmission power to improve image quality, thereby facilitating the user to carefully observe the cross-section.

[0072] Specifically, in step S210, the processor of the ultrasound imaging system controls the ultrasound probe to emit ultrasound waves toward the target tissue, receives the echo signals of the ultrasound waves, and generates an ultrasound image of the target tissue in real time based on the echo signals. See also Figure 1During ultrasound imaging, the transmitting circuit, under the control of the processor, sends a set of delayed-focused pulses to the ultrasound probe to excite the probe to emit ultrasound waves toward the target tissue. The receiving circuit controls the ultrasound probe to receive the ultrasound echo reflected from the target tissue, converts it into an electrical signal, and the beamforming module performs corresponding delay and weighted summation processing on the ultrasound echo signals obtained from multiple transmissions and receptions to achieve beamforming. The signal is then sent to the processor for further signal processing to obtain the ultrasound image of the target tissue. The ultrasound image of the target tissue can be displayed in real time on the ultrasound imaging system's monitor.

[0073] In step S220, the processor obtains a velocity index reflecting the movement speed of the ultrasound probe while controlling the ultrasound probe to emit ultrasound waves towards the target tissue. During the generation of an ultrasound image of the target tissue, the user moves the ultrasound probe to examine the target tissue. The speed of the ultrasound probe's movement reflects the current examination stage, i.e., whether the user is currently searching for or observing a target cross-section. Therefore, this embodiment of the invention obtains a velocity index reflecting the movement speed of the ultrasound probe to determine the motion state of the ultrasound probe.

[0074] For example, since the faster the ultrasound probe moves or the greater its amplitude of movement, the more obvious the changes between adjacent ultrasound images, the motion state of the ultrasound probe can be analyzed by analyzing the changes between adjacent ultrasound images. Specifically, a velocity index reflecting the motion speed of the ultrasound probe can be obtained based on the changes between the current ultrasound image and its neighboring ultrasound images. The current ultrasound image is the ultrasound image currently acquired by the ultrasound imaging system, and the neighboring ultrasound image can be the previous ultrasound image, or it can be the Nth ultrasound image preceding the current ultrasound image. After acquiring the current ultrasound image, an index characterizing the changes between the current ultrasound image and its neighboring ultrasound images is determined as a velocity index reflecting the motion speed of the ultrasound probe.

[0075] The index characterizing the change between the current frame ultrasound image and adjacent frames can be an index characterizing the difference between the current frame ultrasound image and adjacent frames. The larger the value of this index, the greater the difference between the current frame ultrasound image and adjacent frames, and thus the faster the ultrasound probe moves. Specifically, the pixel difference of at least some pixels in the current frame ultrasound image and adjacent frames ultrasound images can be determined; the pixel differences of at least some pixels are accumulated to obtain the accumulated pixel difference, and the speed index is determined based on the accumulated pixel difference.

[0076] For example, the sum of the absolute values ​​D of the pixel differences between each pixel in the current frame ultrasound image and the neighboring frame ultrasound images is represented as:

[0077]

[0078] Where I and J represent the current frame image and the neighboring frame image, respectively, and i and j represent the coordinates of the pixels. A larger D indicates a greater change between the current frame ultrasound image and the neighboring frame ultrasound images, resulting in a faster ultrasound probe movement speed; conversely, a smaller D indicates a smaller change between the current frame ultrasound image and the neighboring frame ultrasound images, resulting in a slower ultrasound probe movement speed. D can be directly used as an indicator of the ultrasound probe's speed, or further calculations such as normalization can be performed on D to obtain the ultrasound probe's speed index.

[0079] Another method for analyzing the motion state of an ultrasound probe involves calculating the similarity between the current frame of the ultrasound image and neighboring frames using a pre-defined similarity algorithm, and then determining the velocity index based on this similarity. A higher similarity indicates less variation between the current and neighboring frames, suggesting a slower probe motion; conversely, a lower similarity indicates greater variation, suggesting a faster probe motion. The pre-defined similarity algorithm can calculate correlation coefficients, histogram similarity, or structural similarity between the current and neighboring frames. The similarity can be used directly as the probe's velocity index, or further calculations can be performed on the similarity to obtain the probe's velocity index.

[0080] Besides determining the speed of the ultrasonic probe based on changes in the ultrasonic image, in some embodiments, the speed of the ultrasonic probe can also be determined by a speed sensor located inside or on the surface of the ultrasonic probe. The processor communicates with the speed sensor to acquire the speed value of the ultrasonic probe sent by the speed sensor in real time. For example, the speed sensor includes an accelerometer, a gyroscope, etc.

[0081] Since a faster ultrasonic probe movement indicates that the probe is currently searching for a cross-section, a higher imaging frame rate is required; and a slower ultrasonic probe movement indicates that the probe is currently observing a cross-section, a lower frame rate can be appropriately reduced, in step S230, the processor adjusts the imaging frame rate of the ultrasonic probe according to the speed index. The speed index reflects that the faster the ultrasonic probe moves, the higher the imaging frame rate; and the slower the ultrasonic probe moves, the lower the imaging frame rate.

[0082] In some embodiments, the processor can adjust the imaging frame rate according to the functional relationship between the imaging frame rate and the speed index, so that the imaging frame rate changes dynamically with the speed index. This functional relationship can be a linear function, polynomial, exponential function, logarithmic function, etc., and is specifically designed based on the principle that the slower the ultrasound probe moves, the lower the imaging frame rate. When the similarity or difference between ultrasound images is used as a speed index reflecting the ultrasound probe's movement speed, the above functional relationship can be a functional relationship between similarity or difference and the imaging frame rate.

[0083] Since the imaging frame rate cannot increase indefinitely, when the processor determines that the speed index is higher than the first speed index, it maintains the imaging frame rate at the first imaging frame rate corresponding to the first speed index; that is, as the speed of the ultrasound probe increases, the imaging frame rate increases accordingly. When the speed index of the ultrasound probe reaches the first speed index, the processor increases the imaging frame rate to the first imaging frame rate corresponding to the first speed index based on the functional relationship between the imaging frame rate and the speed index. When the speed index of the ultrasound probe exceeds the first speed index and continues to rise, the processor no longer increases the imaging frame rate but maintains the first imaging frame rate unchanged. The first imaging frame rate can be the maximum frame rate allowed by the ultrasound imaging system or the conventional frame rate used by the ultrasound imaging system.

[0084] Alternatively, a segmented adjustment method can be used. This involves determining the threshold range for the velocity index and adjusting the imaging frame rate to match that range. For example, the threshold range for the velocity index includes a first threshold range greater than or equal to the second velocity index, and a second threshold range less than the second velocity index. The first threshold range corresponds to the first imaging frame rate, and the second threshold range corresponds to the second imaging frame rate. A velocity index within the first threshold range indicates a faster ultrasound probe movement speed, facilitating the search for the cross-section; a velocity index within the second threshold range indicates a slower ultrasound probe movement speed, facilitating the observation of the cross-section. During ultrasound imaging of the target tissue using the first imaging frame rate, if the detected velocity index is lower than the second velocity index, the imaging frame rate is adjusted from the first to the second imaging frame rate, where the second imaging frame rate is lower than the first. Conversely, during ultrasound imaging of the target tissue using the second imaging frame rate, if the detected velocity index is higher than the second velocity index, the imaging frame rate can be increased back to the first imaging frame rate. It should be noted that the threshold range of the speed index is not limited to two. More threshold ranges can be preset, and a corresponding imaging frame rate can be set for each threshold range, so as to make more precise adjustments to the imaging frame rate.

[0085] To adjust the frame rate of ultrasound imaging, the time interval between two consecutive transmissions from the ultrasound probe, or the time interval between two consecutive ultrasound images, can be adjusted. For example... Figure 3 As shown, multiple scan lines form a frame of ultrasound image. Adjusting the time interval between two adjacent transmissions of the ultrasound probe is equivalent to adjusting the time interval between two adjacent scan lines. For example, when it is necessary to reduce the frame rate, the time interval between two adjacent scan lines can be extended. After one emission and reception of ultrasonic waves, wait for a certain period of time before performing the next emission and reception. Alternatively, the time interval between two adjacent frames of ultrasound images can be extended to reduce the frame rate, that is, after the emission and reception of ultrasonic waves for one frame of ultrasound image, wait for a certain period of time before performing the emission and reception of ultrasonic waves for the next frame of ultrasound image.

[0086] Taking the extension of the time interval between two adjacent frames of ultrasound images as an example, assume the original imaging frame rate is fr, and the target frame rate obtained based on the velocity index is fr1. If fr1 > fr, the imaging frame rate cannot be further increased and still remains fr for imaging; if fr1 < fr, then it is possible to wait for △t = 1 / fr1 – 1 / fr between two adjacent frames (i.e., frame f i and frame f i+1 to achieve the purpose of reducing the imaging frame rate.

[0087] After reducing the imaging frame rate, the ultrasonic waves received by the tissue within the same time are reduced, thereby reducing the temperature rise, so that the mechanical index can be increased without causing the temperature rise to exceed the standard, in order to improve the image quality of the ultrasound image. Therefore, in step S240, the processor obtains the corresponding relationship between the preset imaging frame rate and the transmission power, and adjusts the transmission power of the ultrasound probe according to the imaging frame rate and the above corresponding relationship. Among them, the higher the imaging frame rate, the lower the transmission power, and vice versa, the lower the imaging frame rate, the higher the transmission power. Since the transmission power is proportional to the square of the transmission voltage, the transmission power can also be adjusted by adjusting the transmission voltage.

[0088] In some embodiments, the corresponding relationship between the imaging frame rate and the transmission power can be the corresponding relationship between the adjustment amplitude of the imaging frame rate and the adjustment amplitude of the transmission power, specifically including the corresponding relationship between the increase amplitude of the transmission power and the decrease amplitude of the imaging frame rate, or the corresponding relationship between the decrease amplitude of the transmission power and the increase amplitude of the imaging frame rate. According to the imaging frame rate before adjustment and the imaging frame rate after adjustment, the adjustment amplitude of the imaging frame rate can be determined. According to the adjustment amplitude of the imaging frame rate and the above corresponding relationship, the adjustment amplitude of the transmission power can be determined, and then the transmission power can be adjusted according to the adjustment amplitude of the transmission power. Among them, the greater the adjustment amplitude of the imaging frame rate, the greater the adjustment amplitude of the transmission power, and the smaller the adjustment amplitude of the imaging frame rate, the smaller the adjustment amplitude of the transmission power.

[0089] Exemplarily, the functional relationship between the increase amplitude △P of the transmission power and the decrease amplitude △fr of the imaging frame rate is expressed as:

[0090] △P = f(△fr)

[0091] Where f can be a linear function, polynomial, exponential function, logarithmic function, or piecewise function, etc., and can be specifically designed based on the rule that the greater the decrease in imaging frame rate, the greater the increase in transmission power. In addition to setting the correspondence between the adjustment range of imaging frame rate and the adjustment range of transmission power, the correspondence between imaging frame rate and transmission power can also be set, so as to determine the target transmission power based on the adjusted imaging frame rate and the correspondence.

[0092] Alternatively, when adjusting the imaging frame rate using a segmented adjustment method, a corresponding transmission power can be set for each preset imaging frame rate. After adjusting the imaging frame rate, the transmission power is adjusted to match the adjusted imaging frame rate. For example, when adjusting the imaging frame rate from a first imaging frame rate to a second imaging frame rate, the transmission power is adjusted from the first transmission power corresponding to the first imaging frame rate to the second transmission power corresponding to the second imaging frame rate, based on the preset correspondence between imaging frame rate and transmission power. Thus, when the ultrasound probe moves at a high speed, a high imaging frame rate and a low transmission frame rate are used to ensure imaging speed; when the ultrasound probe moves at a slow speed, a low imaging frame rate and a high transmission power are used to ensure imaging quality and avoid excessive temperature rise.

[0093] In summary, the ultrasound imaging method 200 of this embodiment adjusts the imaging frame rate according to the speed index of the ultrasound probe and adjusts the transmission power of the ultrasound probe according to the imaging frame rate. This allows for the use of a higher frame rate during the search for the cross-section to ensure imaging speed, and a higher transmission power during the observation of the cross-section to ensure imaging quality. At the same time, a lower imaging frame rate is used to avoid excessive temperature rise, thereby ensuring tissue safety.

[0094] This invention also provides an ultrasound imaging system for implementing the ultrasound imaging method 200 described above. The ultrasound imaging system includes an ultrasound probe, a transmitting circuit, a receiving circuit, a processor, and a display. (Refer to previous text) Figure 1 This ultrasound imaging system can achieve the following: Figure 1 The ultrasound imaging system 100 shown may include an ultrasound probe 110, a transmitting circuit 112, a receiving circuit 114, a processor 116, and a display 118. Optionally, the ultrasound imaging system 100 may also include a transmit / receive selection switch 120 and a beamforming module 122. The transmitting circuit 112 and the receiving circuit 114 can be connected to the ultrasound probe 110 through the transmit / receive selection switch 120. The relevant descriptions of each component can be referred to the relevant descriptions above, and will not be repeated here.

[0095] The transmitting circuit 112 controls the ultrasound probe 110 to emit ultrasound waves toward the target tissue; the receiving circuit 114 controls the ultrasound probe 110 to receive the echo of the ultrasound waves returned from the target tissue to obtain an ultrasound echo signal; the processor 116 is used to perform ultrasound imaging based on the ultrasound echo signal; the processor 116 is also used to perform the steps of the ultrasound imaging method 200 described above, namely, obtaining a speed index reflecting the movement speed of the ultrasound probe during the process of controlling the ultrasound probe to emit ultrasound waves toward the target tissue; adjusting the imaging frame rate of the ultrasound probe according to the speed index, wherein the faster the movement speed of the ultrasound probe, the higher the imaging frame rate; and adjusting the transmitting power of the ultrasound probe according to the imaging frame rate, wherein the higher the imaging frame rate, the lower the transmitting power.

[0096] The above only describes the main functions of each component of the ultrasound imaging system. For more details, please refer to the relevant description of the ultrasound imaging method 200, which will not be repeated here. The ultrasound imaging system of this invention can meet the needs of sensitive tissues for both safety and imaging quality.

[0097] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

[0098] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0099] In the several embodiments provided by this invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0100] Numerous specific details are set forth in the specification provided herein. However, it will be understood 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 so as not to obscure the understanding of this specification.

[0101] Similarly, it should be understood that, in order to streamline the invention and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of the invention. However, this approach should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0102] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0103] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0104] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules according to embodiments of the present invention. The present invention can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing some or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0105] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0106] The above description is merely a specific embodiment of the present invention or an explanation of that embodiment. The scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An ultrasound imaging method for an ultrasound imaging system, the ultrasound imaging system comprising an ultrasound probe, a transmitting circuit, a receiving circuit, and a processor, characterized in that, The method includes: The processor controls the ultrasound probe to emit ultrasound waves toward the target tissue, receives the echo signals of the ultrasound waves, and generates an ultrasound image of the target tissue in real time based on the echo signals of the ultrasound waves. During the process of controlling the ultrasonic probe to emit ultrasonic waves toward the target tissue, the processor obtains a speed index reflecting the movement speed of the ultrasonic probe. The processor adjusts the imaging frame rate of the ultrasound probe according to the speed index, wherein the speed index reflects that the faster the ultrasound probe moves, the higher the imaging frame rate. The processor acquires a pre-set correspondence between imaging frame rate and transmission power, and adjusts the transmission power of the ultrasound probe according to the imaging frame rate and the correspondence to avoid excessive temperature rise. The higher the imaging frame rate, the lower the transmission power. The correspondence between the imaging frame rate and the transmission power includes the correspondence between the imaging frame rate adjustment range and the transmission power adjustment range. Adjusting the transmission power of the ultrasound probe according to the imaging frame rate and the correspondence includes: The adjustment range of the imaging frame rate is determined based on the imaging frame rate before and after adjustment. The transmission power adjustment range is determined based on the correspondence between the imaging frame rate adjustment range and the transmission power adjustment range, wherein the larger the imaging frame rate adjustment range, the larger the transmission power adjustment range. The transmission power is adjusted according to the specified transmission power adjustment range; Alternatively, adjusting the transmission power of the ultrasound probe according to the imaging frame rate includes: When the imaging frame rate is adjusted from the first imaging frame rate to the second imaging frame rate, the transmission power is adjusted from the first transmission power corresponding to the first imaging frame rate to the second transmission power corresponding to the second imaging frame rate, according to the correspondence between the imaging frame rate and the transmission power.

2. The ultrasound imaging method according to claim 1, characterized in that, The process of obtaining the velocity index reflecting the movement speed of the ultrasonic probe includes: A velocity index reflecting the movement speed of the ultrasound probe is obtained based on the changes between the current frame ultrasound image and its neighboring frames ultrasound images.

3. The ultrasound imaging method according to claim 2, characterized in that, The step of obtaining a velocity index reflecting the motion speed of the ultrasound probe based on the change between the current frame ultrasound image and its neighboring frames ultrasound images includes: Determine the pixel differences between at least a portion of the pixels in the current frame ultrasound image and the neighboring frame ultrasound images; The pixel differences of at least some of the pixels are accumulated to obtain an accumulated pixel difference, and the speed index is determined based on the accumulated pixel difference.

4. The ultrasound imaging method according to claim 2, characterized in that, The step of obtaining a velocity index reflecting the motion speed of the ultrasound probe based on the change between the current frame ultrasound image and its neighboring frames ultrasound images includes: The similarity between the current frame ultrasound image and the neighboring frame ultrasound images is calculated according to a preset similarity algorithm, and the speed index is determined based on the similarity.

5. The ultrasound imaging method according to claim 1, characterized in that, Adjusting the imaging frame rate of the ultrasound imaging according to the speed index includes: The imaging frame rate is adjusted according to the functional relationship between the imaging frame rate and the speed index, so that the imaging frame rate changes dynamically with the speed index.

6. The ultrasound imaging method according to claim 5, characterized in that, The method further includes: When the processor determines that the speed index is higher than the first speed index, it maintains the imaging frame rate at the first imaging frame rate corresponding to the first speed index.

7. The ultrasound imaging method according to claim 1, characterized in that, Adjusting the imaging frame rate of the ultrasound imaging according to the speed index includes: Determine the threshold range in which the speed index falls, and adjust the imaging frame rate to the imaging frame rate corresponding to the threshold range.

8. The ultrasound imaging method according to claim 7, characterized in that, The step of determining the threshold range in which the speed index falls and adjusting the imaging frame rate to an imaging frame rate corresponding to the threshold range includes: During ultrasound imaging of the target tissue using a first imaging frame rate, if the speed index is detected to be lower than a second speed index, the imaging frame rate is adjusted from the first imaging frame rate to the second imaging frame rate, where the second imaging frame rate is lower than the first imaging frame rate.

9. The ultrasound imaging method according to claim 1, characterized in that, Adjusting the imaging frame rate of the ultrasound imaging according to the speed index includes: The imaging frame rate of the ultrasound imaging is adjusted by adjusting the time interval between two adjacent transmissions of the ultrasound probe and / or adjusting the time interval between two adjacent ultrasound images.

10. An ultrasound imaging system, characterized in that, The ultrasound imaging system includes: Ultrasonic probe; A transmitting circuit is used to excite the ultrasound probe to emit ultrasound waves toward the target tissue. A receiving circuit is used to control the ultrasonic probe to receive the echo of the ultrasonic wave in order to obtain the echo signal of the ultrasonic wave. A processor for performing the steps of the ultrasound imaging method according to any one of claims 1-9; A display for showing the ultrasound images generated by the processor.

Images