HK40032981B - Method, system and data storage medium for biological tissue elasticity measurement in multi-dimension - Google Patents

Description

A dimensional method for detecting the elasticity of biological tissues, including a detection system and storage medium.

Technical Field

This invention relates to the field of ultrasound diagnostic technology, and in particular to an elastic detection method, detection system, and storage medium for dimensional measurement of biological tissues.

Background Technology

Some liver diseases may cause fibrosis to be non-widespread, resulting in uneven stiffness of the liver parenchyma. Existing elastography and measurement techniques for biological tissues include transient elastography, supersonic shear imaging, acoustic radiation force elastography (ARFI) elastography, and strain elastography. Transient elastography typically uses pulsed vibrations and measures the propagation of shear waves for elasticity measurement and imaging. Transient elastography, which utilizes external vibrations to generate shear waves propagating within the liver, is a relatively simple and low-cost approach, and is therefore widely used clinically. However, existing transient liver elastography techniques can only perform single-value measurements, employing a fixed-depth sampling strategy and measuring only scalar values (numerical magnitude, but no dimensionality). To obtain dimensional elastic distribution within the liver, the probe must be manually moved at the detection point on the body surface, which is time-consuming and labor-intensive. Currently, the widely accepted approach to existing transient liver elastography techniques involves quantifying the degree of liver fibrosis by performing multiple effective single-value measurements and calculating the median. However, this approach results in low efficiency, and the reliability and reproducibility of the results are highly dependent on the operator.

The drawbacks of single-value elasticity measurement techniques are that they can only be sampled once and that sampling errors exist (i.e., spatial distribution information cannot be obtained). Existing technology (publication number CN101843501A) describes methods and instruments for calculating elasticity parameters using B-mode ultrasound imaging and constructed transient M-mode images; however, it does not elaborate on a specific scheme for achieving dimensional elasticity measurement. Dimensional elasticity measurement can more intuitively display the spatial distribution of elasticity, which has clinical significance for the diagnosis and monitoring of lesions.

Summary of the Invention

This invention addresses the problems of sampling error and low detection reliability in existing technologies by providing an elasticity detection method, detection system, and storage medium that utilizes an ultrasonic transducer array to perform dimensional biological tissue elasticity measurement, achieving a low sampling error rate.

The technical solution proposed by this invention to address the above-mentioned technical problems is as follows:

This invention provides a dimensional elasticity detection method for detecting biological tissues. The method includes the following steps: acquiring an ultrasound image of a target object; in response to external vibration excitation, collecting elastic feature parameters at specified coordinate positions of the target object and mapping them to generate an elasticity mapping map; and superimposing and fusing the elasticity mapping map containing elasticity distribution data onto the ultrasound image and displaying it synchronously.

According to the above method, the ultrasound image is a two-dimensional ultrasound image containing anatomical information of the target object, used to locate the position of the target object; based on the ultrasound image, a coordinate system for sampling the region of interest is established, and the number of sampling points and their coordinate distribution positions are determined; the region of interest is located within the selected ultrasound image and is one of the coordinate systems of a single-axis straight line, a two-dimensional plane, or a three-dimensional space; based on the coordinate system dimension and position of the selected region of interest, the sampling points are specific coordinate points located in the coordinate system and can be distributed according to specific positions.

According to the above method, the specific steps for collecting elastic characteristic parameters of a specified region of the target object and mapping them to generate an elastic mapping map include: measuring the elastic characteristic parameters of sampling points of the target object: applying low-frequency mechanical vibration to the probe on the body surface to generate shear waves that propagate within the biological tissue; controlling the corresponding array elements in the ultrasonic transducer array to transmit and receive ultra-high frame rate ultrasonic waves to track the shear waves along the specified coordinate positions or different directions of each sampling point, and simultaneously or with delays, performing parameter measurements at multiple sampling points; mapping to generate an elastic mapping map: using mapping technology, encoding the elastic characteristic parameters at the specified coordinate positions into a single-value mapping map or a color mapping map to characterize the distribution state of the elastic characteristics; the elastic characteristic parameters are parameters related to the elasticity of biological tissues, including elastic parameters, ultrasonic parameters, and two-dimensional ultrasonic image feature parameters; the elastic parameters can be expressed by Young's modulus.

According to the above method, the probe is triggered to emit a directional ultra-high frame rate ultrasonic signal to track the shear wave for sampling. Before sampling, the time delay of the transducer array element of the probe emitting and receiving ultrasonic waves is calculated. The sampling modes include: obtaining a radio frequency (RF) signal by exciting a single array element of the probe and calculating the elastic characteristic parameters at a specified position in a one-dimensional space; or obtaining a radio frequency (RF) signal by controlling different array elements of the probe in parallel and calculating the elastic characteristic parameters at a specified position in a multi-dimensional space.

According to the above method, the dimensional elasticity detection method includes one-dimensional, two-dimensional, and three-dimensional ultrasound instantaneous elasticity detection, specifically including the following processing steps: acquiring a two-dimensional ultrasound image; determining the location of the region of interest (ROI) on the two-dimensional ultrasound image; establishing a sampling coordinate system of the corresponding dimension in the ROI; determining the number and coordinate positions of sampling points in the selected corresponding dimension sampling coordinate system; measuring at least one elastic feature parameter at each selected sampling point in the ROI using a probe; mapping and processing the corresponding elastic feature parameters measured at each sampling point to construct an elasticity mapping map of the corresponding dimension sampling coordinate system; and superimposing and fusing the elasticity mapping map of the corresponding dimension onto the two-dimensional ultrasound image and displaying it synchronously.

According to the above method, the three-dimensional data acquisition of the three-dimensional ultrasonic instantaneous elasticity detection is achieved by using a two-dimensional array probe fixedly placed at a single detection point on the body surface and performing single-point detection; or by using a linear array probe, phased array probe, or convex array probe to move on multiple detection points on the body surface and performing multi-point detection.

According to the above method, the external vibration excitation is applied continuously at a certain repetition frequency, and the ultra-high frame rate ultrasound will simultaneously track the propagation of multiple shear waves generated in the biological tissue by continuous vibration.

According to the above method, the acquisition of ultra-high frame rate ultrasound will be carried out simultaneously in at least two positions or directions.

This invention also provides a dimensional elasticity detection system for detecting biological tissues, comprising an image acquisition unit for acquiring ultrasound images of a target object and a probe for transmitting and receiving ultrasound signals; the detection system further comprises: a main control unit, connected to the image acquisition unit and the probe respectively, for establishing a coordinate system of a sampling region of interest in a corresponding dimension based on the acquired ultrasound image of the target object, determining the number and coordinate distribution of sampling points; receiving elasticity feature parameters of the region of interest corresponding to the target object, mapping to generate an elasticity mapping map, and superimposing and fusing the elasticity mapping map containing elasticity distribution data onto the ultrasound image and displaying it synchronously.

According to the above device, the probe includes: an ultrasonic probe and a low-frequency vibrator coupled to the ultrasonic probe. The ultrasonic probe consists of several ultrasonic piezoelectric transducer elements arranged in a linear array, convex array, or two-dimensional array. The low-frequency vibrator continuously applies mechanical vibration to the body surface at a certain repetition frequency, generating multiple shear waves that propagate within biological tissues by continuous vibration.

According to the above-described device, the main control unit includes a control unit and a processing unit. The control unit is connected to the image acquisition unit, the probe, and the processing unit, respectively. The control unit is used to receive the ultrasound image from the image acquisition unit and transmit the ultrasound image to the processing unit. The processing unit is used to determine the distribution coordinates of sampling points in the region of interest based on the ultrasound image and transmit the distribution coordinate information of the sampling points to the control unit. The control unit is also used to control the low-frequency vibrator to send shear waves to the target object according to the distribution coordinates of the sampling points, and the ultrasound transducer array elements of the probe to send ultra-high frame rate ultrasound signals to the distribution coordinates of the sampling points, and to receive the RF signals fed back from the distribution coordinates of the sampling points. The control unit also transmits the RF signals and their distribution data acquired by the probe to the processing unit. The processing unit is also used to calculate the corresponding elastic characteristic parameters based on the received RF signals and their distribution data of each coordinate, establish a one-dimensional or multi-dimensional elastic mapping map, and fuse the corresponding mapping map with the ultrasound image. The fused image is displayed synchronously through a display unit connected to the processing unit.

In a third aspect, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor CPU, causes the processor CPU to perform the following steps: acquiring an ultrasound image of a target object; in response to an external vibration excitation, acquiring elastic characteristic parameters at specified coordinate positions of the target object and mapping them to generate an elastic mapping map; and superimposing and fusing the elastic mapping map containing elastic distribution data onto the ultrasound image and displaying it synchronously.

The beneficial effects of the technical solution provided by the embodiments of the present invention are as follows:

This invention addresses the limitations of existing single-value elasticity measurement techniques, which can only perform single sampling and cannot obtain spatial distribution information. It provides a detection method that eliminates the need for manual probe movement, enabling multiple samplings at a single detection point to simultaneously measure multiple elastic characteristic parameters and synthesize an elasticity distribution map. By controlling the corresponding array elements in the ultrasonic transducer array to transmit and receive ultra-high frame rate ultrasound waves, elastic characteristic parameters with multiple spatial distributions are acquired and mapped to generate single-value or color elasticity maps. Image processing and overlay fusion of the elasticity maps containing elasticity distribution data into the ultrasound image visualizes the spatial distribution of elastic characteristics in biological tissues. This invention measures multiple elastic characteristic parameters within a certain range using a single examination point, improving examination efficiency and saving time. Increased sample size minimizes system errors, improving result reliability and reducing sampling errors. Furthermore, it provides adjustable and switchable sampling point distribution modes that can selectively avoid large blood vessels and the bile duct system, obtaining the distribution of biological parameters in biological tissues for more accurate and customized results.

Attached Figure Description

Figure 1 is a schematic flowchart of the dimensional biological tissue elasticity detection method provided in Embodiment 1 of the present invention.

Figure 2 is a block diagram of a dimensional biological tissue elasticity detection system provided in Embodiment 2 of the present invention.

Figure 3 is a schematic diagram of the one-dimensional and two-dimensional ultrasonic instantaneous elasticity detection process provided in Embodiment 1 of the present invention.

Figure 4 is a schematic diagram of the liver one-dimensional elasticity detection method provided in Embodiment 1 of the present invention.

Figure 5 is a schematic diagram of the liver two-dimensional elasticity detection method provided in Embodiment 1 of the present invention.

Figure 6 is an example diagram of the synthetic two-dimensional mapping diagram provided in Embodiment 1 of the present invention.

Figure 7 is a schematic diagram of the three-dimensional ultrasonic instantaneous elasticity detection process provided in Embodiment 1 of the present invention.

Figure 8 is a schematic diagram of the liver three-dimensional elasticity detection method provided in Embodiment 1 of the present invention.

Detailed Implementation

To address the technical problems of high sampling error rate, low inspection efficiency, and low result reliability in existing technologies, this invention aims to provide a method for dimensional elasticity detection of biological tissues using an ultrasonic transducer array. The core idea is to acquire ultrasonic images of the target object using the ultrasonic transducer array, establish a coordinate system for sampling regions of interest, determine the number and specific coordinate distribution of sampling points, and, in response to external vibration excitation, collect multiple elastic feature parameters at specified coordinate locations. The parameter values containing spatial location information are then reconstructed with the corresponding ultrasonic images, including the synthesis, overlay fusion, and synchronous display of mapping maps, to obtain one-dimensional, two-dimensional, and three-dimensional elasticity distributions of biological tissues. The dimensional elasticity detection system employed in this invention, by controlling the corresponding array elements in the transducer array to transmit and receive ultra-high frame rate ultrasonic waves and post-processing the RF signals and images, can visualize the spatial distribution of the elastic features of biological tissues. A low-frequency vibrator emits low-frequency vibrations towards the target object to generate shear waves; an ultrasonic probe emits and receives ultrasonic waves from the target object to obtain ultrasonic images, and receives RF signals fed back from the sampling point distribution coordinates of the target object; a processing unit within the system receives the RF signals and distribution data of the region of interest of the target object, maps them to generate a one-dimensional, two-dimensional, or three-dimensional elastic mapping map of the target object, and superimposes and fuses the elastic mapping map containing elastic distribution data onto the ultrasonic image and displays it synchronously through a display unit. This invention can measure multiple elastic characteristic parameters within a certain range using a single inspection point, which not only improves inspection efficiency but also minimizes sampling errors.

To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

Embodiment 1 of the present invention provides a flowchart of a method for detecting the elasticity of biological tissue with dimensionality (in this embodiment, the biological tissue used is the liver), as shown in Figure 1. The method mainly includes the following processing steps:

S100: Acquire ultrasound images of the target object.

The process involves using an ultrasound transducer to emit ultrasound waves and receive the echo signals reflected from the liver to obtain a morphological image of the liver. Simultaneously, a region of interest (ROI) is identified, a sampling coordinate system is established within the ROI, and the number and coordinate positions of sampling points are specified. The morphological image of the target object includes a two-dimensional ultrasound image containing information about the liver's anatomical structure, including B-mode ultrasound images, color Doppler images, and power Doppler images.

S200. In response to external vibration excitation, the elastic characteristic parameters of the target object at a specified coordinate position are collected and mapped to generate an elastic mapping diagram.

The specific steps include: measuring the elastic characteristic parameters of sampling points on the target object and generating an elastic mapping map. Measuring the elastic characteristic parameters of the sampling points involves: applying low-frequency mechanical vibration to the probe on the body surface to generate shear waves that propagate within the biological tissue; controlling the corresponding array elements in the ultrasound transducer array to transmit and receive ultra-high frame rate ultrasound waves to track the shear waves along specified coordinate positions or different directions at each sampling point, simultaneously or with delays, performing parameter measurements at multiple sampling points; the acquisition of the ultra-high frame rate ultrasound waves is performed simultaneously at at least two positions or directions; the elastic characteristic parameters are parameters related to the elasticity of the liver, including elastic parameters, ultrasound parameters, and two-dimensional ultrasound image feature parameters; the elastic parameters can be expressed by Young's modulus. Generating the elastic mapping map involves using mapping technology to encode the elastic characteristic parameters at specified coordinate positions into a single-value mapping map or a color elastic mapping map to characterize the distribution of elastic characteristics. The mapping map can be a one-dimensional, two-dimensional, or three-dimensional image.

S300: The elastic mapping map containing elastic distribution data is superimposed and fused into the ultrasound image and displayed synchronously.

The above detection method includes one-dimensional, two-dimensional, and three-dimensional ultrasonic transient elasticity detection, and further includes the following processing steps: acquiring a two-dimensional ultrasound image; determining the location of a region of interest (ROI) on the two-dimensional ultrasound image; establishing a sampling coordinate system of the corresponding dimension in the ROI; determining the number of sampling points in the selected corresponding dimension sampling coordinate system; measuring at least one elastic feature parameter at each selected sampling point in the ROI using a probe; mapping and processing the corresponding elastic feature parameters measured at each sampling point to construct an elasticity mapping map of the corresponding dimension sampling coordinate system; and superimposing and fusing the elasticity mapping map of the corresponding dimension onto the two-dimensional ultrasound image and displaying it synchronously.

The three-dimensional data acquisition for the three-dimensional ultrasonic instantaneous elasticity detection is achieved by using a two-dimensional array probe fixedly placed at a single detection point on the body surface for single-point detection; or by using a linear array probe, phased array probe, or convex array probe to move across multiple detection points on the body surface for multi-point detection.

The process involves triggering the probe to emit a directional, ultra-high frame rate ultrasonic signal to track shear waves for sampling. Before sampling, the time delay between the transmission and reception of ultrasonic waves by the corresponding transducer element is calculated. This time delay refers to the backscattering or reflection of ultrasonic waves during their propagation within tissue, which are then received by the transducer element. The time of signal reception corresponds one-to-one with the depth of the sampling point; therefore, by controlling the time delay between reception and transmission, ultrasonic signals at a specified depth and direction can be selectively received. Furthermore, the sampling modes include: obtaining radio frequency (RF) signals by exciting a single element of the probe and calculating elastic characteristic parameters at a specified location in one-dimensional space; or obtaining RF signals by controlling different elements of the probe in parallel and calculating elastic characteristic parameters at a specified location in multi-dimensional space.

Referring to Figure 2, a dimensional elasticity detection system of Embodiment 2 is provided. This system is applied to the detection method for biological tissues in Embodiment 1 (in this embodiment, the selected biological tissue is the liver). The elasticity detection system includes an image acquisition unit 10 for acquiring ultrasound images of the target object and a probe 20 for transmitting and receiving ultrasound signals. The detection system also includes a main control unit 30, which is connected to the image acquisition unit 10, the probe 20, and a display unit 40. The main control unit 30 is used to establish a coordinate system of the corresponding dimension of the sampling region of interest based on the acquired ultrasound image of the target object, determine the number and coordinate distribution of sampling points, receive the elasticity feature parameters of the region of interest corresponding to the target object, map and generate an elasticity mapping map of the target object, and superimpose and fuse the elasticity mapping map containing elasticity distribution data onto the ultrasound image and display it synchronously. The control unit is also used to control the low-frequency vibrator to send shear waves to the target object according to the sampling point distribution coordinates, and the ultrasound transducer array elements of the probe to send ultra-high frame rate ultrasound signals to the sampling point distribution coordinates, receive the RF signals fed back from the sampling point distribution coordinates, and transfer the RF signals and their distribution data acquired by the probe to the processing unit.

The processing unit is also used to calculate the corresponding elastic characteristic parameters based on the received RF signals and their distribution data of each coordinate, establish a multi-dimensional elastic mapping map, and fuse the corresponding mapping map with the ultrasound image.

The probe 20 includes: an ultrasonic probe 21 that emits ultrasonic waves towards a target object and receives echoes from the target object to obtain ultrasonic images, and receives RF signals fed back from the sampling point distribution coordinates of the target object; and a low-frequency vibrator 22 coupled to the ultrasonic probe for emitting mechanical vibrations to the target object to generate shear waves. The low-frequency vibrator 22 generates mechanical shear waves with a center frequency between 10 Hz and 1000 Hz, which are transmitted to the liver tissue via the body surface. Preferably, the liver elasticity detection location is selected at the intercostal space on the body surface. The low-frequency vibrator 22 is coupled to the ultrasonic probe 21 on the same straight line perpendicular to the transducer array element arrangement. The ultrasonic probe 21 serves as both the vibration source of the mechanical shear waves and the detection head for elasticity measurement. The ultrasonic probe 21 consists of several ultrasonic piezoelectric transducer elements arranged in a linear array, convex array, or two-dimensional array; preferably, the ultrasonic piezoelectric transducers are arranged in a linear array. The ultrasonic probe 21 operates in two common ultrasonic modes. The first mode is B-mode ultrasound imaging: the ultrasound beam performs mechanical or electronic scanning at a frame rate of approximately 10 to 100 frames per second, and a B-mode ultrasound image is constructed by the image processing unit 32a in the main control unit 30. Generally, the B-mode ultrasound image can be obtained through linear scanning or phase-controlled scanning. The extracted tissue morphology information can be used for diagnosis and to guide the localization of the examined site. The second mode is ultra-high frame rate A-mode ultrasound acquisition: using delay elements, selected transducer array elements are controlled to simultaneously or sequentially output ultra-high frame rate ultrasound signals (at least 1000 frames per second) and receive radio frequency (RF) signals to track the propagation of shear waves within the target area, thereby observing minute displacements of liver tissue exposed to low-frequency shear waves.

The main control unit 30 includes a control unit 31, a processing unit 32, and a storage unit 33. The control unit 31 is connected to the image acquisition unit 10, the probe 20, and the processing unit 32, respectively. The processing unit 32 is connected to the storage unit 33. The control unit 31 receives the ultrasound image from the image acquisition unit 10 and transmits the ultrasound image to the processing unit 32. The processing unit 32 determines the distribution coordinates of sampling points in the region of interest based on the ultrasound image and transmits the distribution coordinate information of the sampling points to the control unit 31. The control unit 31 controls the low-frequency vibrator of the probe 20 according to the distribution coordinates of the sampling points. A shear wave is sent to the target object, and the ultrasonic transducer array elements of probe 20 send ultra-high frame rate ultrasonic signals to the sampling point distribution coordinates. The RF signal fed back from the sampling point distribution coordinates is received, and the RF signal and its distribution data acquired by probe 20 are transferred to processing unit 32. Processing unit 32 also calculates the corresponding elastic characteristic parameters based on the received RF signals and their distribution data of each coordinate, establishes a multi-dimensional elastic mapping map, and fuses the corresponding mapping map with the ultrasonic image. The fused image is synchronously displayed through display unit 40 connected to processing unit 32.

The control unit 31 is responsible for controlling the functional activities and data transmission of each component. It should be specifically noted that the operation of the control unit 31 also includes generating specific delayed timing pulses through delay elements, acting on different transducer array elements to control their timing triggering and acquiring RF signals of the region of interest. The processing unit 32 mainly consists of an image processing unit 32a, an elasticity processing unit 32b, and an image and elasticity parameter reconstruction unit 32c. The image processing unit 32a can generate B-mode ultrasound images containing tissue morphology information; the elasticity processing unit 32b can analyze the RF signals of the echo and calculate the shear wave propagation velocity, thereby converting it into liver biological parameters related to elastic characteristics at the target location; the operation of the image and elasticity parameter reconstruction unit 32c includes: 1) mapping elasticity feature parameters to a single-value distribution image using single-value mapping, and mapping elasticity feature parameters to a grayscale or color image using color mapping, forming a one-dimensional or two-dimensional elasticity mapping map; 2) synthesizing multiple two-dimensional mapping maps into a three-dimensional mapping map; 3) realizing the fusion processing of B-mode ultrasound images (describing the morphological features of liver tissue, etc.) and elasticity mapping maps (describing the elastic features of liver tissue, etc.). Storage unit 33 contains software execution code and algorithm programs.

The display unit 40 is used to display the constructed B-mode ultrasound images, transient M-mode images, and measurement results, including elasticity mapping diagrams; it can also serve as a medium for user interaction, used to obtain user operation commands. The input terminal of the display unit 40 is connected to the output terminal of the main control unit 30, and can be carried by a personal computer or integrated with the main control unit 30 into a single unit. Data transmission can be wireless or wired, and is not limited to Bluetooth, WiFi, cable, or pluggable USB cables.

Specifically, referring to Figure 3, the processing steps for one-dimensional and two-dimensional ultrasonic transient elasticity testing are introduced, and the main workflow is as follows;

S100A, Steps for acquiring ultrasound images of the target object: Acquire B-mode ultrasound images to guide the localization of the examined liver tissue and determine the detection points on the body surface; Determine the location of the region of interest on the B-mode ultrasound image and establish a coordinate system for sampling the region of interest; Within the selected B-mode ultrasound image, determine the number of sampling points within the region of interest of the target object; Within the selected B-mode ultrasound image, based on the number of selected sampling points, determine the distribution pattern of the sampling points within the region of interest;

The ultrasound probe 21 scans the imaging cross-section with an ultrasound beam, providing an image processing unit 32a with a B-mode ultrasound cross-sectional image of the liver tissue. Using real-time guidance from biological tissue anatomical information, the placement and angle of the probe 20 are manually or automatically adjusted to determine the optimal field of view (FOV).

S200A, Step 1: Collect elastic feature parameters in the region of interest and generate an elastic mapping map: trigger the generation and propagation of shear waves; measure at least one elastic feature parameter at each sampling point in the region of interest using a probe; perform mapping and post-processing on the corresponding elastic feature parameters measured at each sampling point to construct a one-dimensional or two-dimensional elastic mapping map.

Within a selected B-mode ultrasound image, determine the number of sampling points K within the region of interest (ROI). The ROI can be a coordinate system with a single-axis linear direction (N), a two-dimensional plane (NM), or a three-dimensional space (NML). The linear direction and two-dimensional plane should be understood as parallel to the imaging section of the B-mode ultrasound image, i.e., the direction of ultrasound propagation; the three-dimensional space should be understood as consisting of several ROIs in two-dimensional planes.

Within a selected B-mode ultrasound image, the distribution pattern of the sampling points is determined based on the number of selected sampling points: relative to the coordinate system dimension of the region of interest, the coordinates of the sampling points can be X _n (N _{_n} ), where 1 ≤ n ≤ K; X _{_nm} (N_n, M _m), where 1 ≤ n, m ≤ K; X _{_nml} (N_n, _M _{_m} , L_{_l}), where 1 ≤ n, m, l ≤ K. The distribution pattern is understood as the positional arrangement of each sampling point in the coordinate system.

The basic principle for triggering the generation and propagation of shear waves is to apply an internal (self-generated) or external excitation to the liver tissue, which can be dynamic, static, or quasi-static. Preferably, the excitation method is external dynamic excitation: a classic implementation involves applying mechanical vibration to the body surface using a low-frequency vibrator 22, triggering the propagation of low-frequency shear waves within the biological tissue. The tissue will respond accordingly based on its physical properties, including displacement, strain, and shear wave velocity. The external vibration excitation is applied continuously at a certain repetition frequency. This invention does not limit the range of the repetition frequency of the vibration. Specific implementations include: 1. While the shear wave generated by the previous vibration is still propagating within the biological tissue, the next vibration will be excited; 2. Just as the shear wave generated by the previous vibration stops propagating within the biological tissue, the next vibration will be excited; 3. After the shear wave generated by the previous vibration stops propagating within the biological tissue, the next vibration will be excited at specific time intervals. When multiple shear waves generated by continuous vibration propagate within the biological tissue, the ultra-high frame rate ultrasound will simultaneously track these shear waves. Other non-limiting implementations may include vibrations, pressure, impacts, and acoustic radiation forces generated by focused ultrasound waves, either externally or internally (due to heartbeats or respiratory movements).

At least one parameter is measured at each sampling point within the region of interest. Multi-point measurements are performed on the sampling points in the selected coordinate system: different subsets of transducer elements transmit ultra-high frame rate ultrasonic signals to each sampling point in a specific time sequence, and then the RF signals reflected back by the corresponding liver tissue are acquired. To characterize the response of the biological tissue surface after being excited by external vibration, a specific embodiment may involve: analyzing the RF echo information of each sampling point through the elastic processing unit 32b to calculate biomechanical parameters; classically, this involves deriving the elastic intrinsic value: Young's modulus.

E = 3ρv ²

Where E is Young's modulus;

Biomechanical parameters, described in a non-restrictive manner, are mechanical and physical properties related to tissue elasticity, and can include Young's modulus, shear wave velocity, shear wave attenuation coefficient, Poisson's ratio, shear modulus, bulk modulus, etc.

Other non-limiting characteristic parameters can be ultrasound parameters and B-mode ultrasound image characteristic parameters. Regarding ultrasound parameters in liver tissue, these can be, in a non-limiting manner, ultrasound velocity, ultrasound attenuation, ultrasound backscattering coefficient, etc. The expression for ultrasound propagation in tissue can be expressed as:

I _d = I ₀ e ^-∝d

Where I _₀ represents the ultrasonic intensity at the initial position, I _{_d} represents the ultrasonic intensity at a propagation distance of t, and t is the ultrasonic attenuation coefficient.

Ultrasound image feature parameters are understood, in a non-limiting sense, as color features, texture features, shape features, spatial relationship features, etc. The most common implementation involves extracting texture feature parameters through digital image processing techniques, specifically the statistical analysis of the gray-level distribution function of local image properties. Texture analysis methods can include statistical analysis methods, structural analysis methods, signal processing methods, and modeling methods.

S300A, Fusion and Display Steps: The one-dimensional or two-dimensional elastic mapping map synthesized by color mapping or single-value mapping is superimposed and fused to the B-mode ultrasound image and displayed synchronously.

Referring further to Figure 4, which provides a schematic diagram of a one-dimensional liver elasticity testing method, a probe 20, composed of a linear array ultrasound probe 32, is placed on the skin outside the intercostal space 401, with the liver tissue 402 being tested located opposite the contact surface. The region of interest 403 contains n sampling points in the longitudinal depth direction (i.e., a linear coordinate system), namely _X1 , _X2 , _X3 , ..., _Xn (n = 1, 2, 3, ..., n ≥ 1). Generally, the longitudinal depth N refers to the direction of ultrasound propagation. It is worth noting that this invention does not limit the specific number of sampling points or their spacing in the one-dimensional direction.

Referring further to Figure 5, which provides a schematic diagram of the two-dimensional liver elasticity detection method, the region of interest 501 (i.e., a Cartesian coordinate system) contains n×m sampling points, namely _X11 , _X12 , _X23 , ..., _Xnm (n = 1, 2, 3, ..., n ≥ 1; m = 1, 2, 3, ..., m ≥ 1), arranged in a matrix. Generally, the region of interest 501 plane has two directional axes, namely the longitudinal depth N and the transverse length M. The transverse length refers to the direction perpendicular to the direction of ultrasound propagation. It is worth noting that this invention does not limit the specific number of sampling points or their arrangement in the two-dimensional direction.

The post-processing steps for fusion and overlay are used to display the measurement results: To visualize the one-dimensional distribution, the corresponding parameters _y1 , _y2 , _y3 , ..., _yn (n = 1, 2, 3, ..., n ≥ 1) measured at each sampling point _X1 , _X2 , _X3 , ..., _Xn (n = 1, 2, 3, ..., n ≥ 1) are post-processed. To visualize the two-dimensional distribution, the corresponding parameters _y11 , _y12 , _y23 , ..., _yn (n = 1, 2, 3, ..., n ≥ 1; m = 1, 2, 3, ..., m ≥ 1) measured at each sampling point _X11 , _X12 , _X23 , ..., _Xnm (n = 1, 2, 3, ..., n ≥ 1; m = 1, 2, 3, ..., m ≥ 1) are post-processed. A typical application is to map elasticity parameter values onto an image, representing them as color codes or scalars (specific numerical values), and displaying them via display unit 40. One implementation could be a reconstruction unit 32c providing the image and elasticity parameters, constructing a mapping map (represented in color or grayscale) through mathematical processing methods such as interpolation and fitting. Preferably, two-dimensional/three-dimensional elasticity mapping maps are superimposed and fused onto a B-mode ultrasound image. The elasticity mapping map represents elasticity feature information using color-coded grayscale or color images, mapping the liver elasticity intensity at specific spatial locations to the corresponding image locations, with different colors or grayscale values representing the elasticity distribution. Correspondingly, the elasticity mapping map is also equipped with a scale bar, interpreting the intensity value encoding of the elasticity mapping map through color gradation and reading range. It should be particularly noted that the result of the fused display is that morphological feature information and elasticity feature information are simultaneously displayed in the same image. To quantify the degree of liver fibrosis and improve the reliability of a single test result, taking the aforementioned one-dimensional elasticity test method as an example, the result Z can be expressed as the mean calculated by the formula: Z = ( _y1 + _y2 + _y3 + ... + _yn )/n. Without limitation, the result Z can also be a calculated value obtained through other mathematical and statistical methods, including the median, variance, quartiles, and normal distribution.

Referring further to Figure 6, which shows an example of the synthesis of the two-dimensional mapping map, the region of interest 501 includes several sampling points arranged in a custom pattern. It is worth noting that the sampling points are placed to avoid non-liver parenchyma tissues (such as intrahepatic vessels, bile ducts, and ligaments). The white arrows indicate intrahepatic vessels. The elastic parameters ( _y11 to _y45 ) measured from each sampling point ( _X11 to _X45 ) contain the following information: Young's modulus (indicating the numerical value) and location information (indicating spatial distribution), forming a single-value mapping map 601. A two-dimensional elastic grayscale mapping map 602 is generated using mapping encoding technology, and is equipped with scale bars 603 for interpretation.

Further refer to Figure 7, which shows a schematic diagram of the three-dimensional ultrasonic instantaneous elasticity testing process; the specific steps include:

S100B, Steps for acquiring ultrasound images of the target object: Acquire B-mode ultrasound images to guide the localization of the examined liver tissue; within the selected B-mode ultrasound images, determine the number of sampling points within the region of interest of the target object; within the selected B-mode ultrasound images, based on the number of selected sampling points, determine the distribution pattern of the sampling points within the region of interest;

S200B, the steps for acquiring three-dimensional data and mapping to generate a three-dimensional elastic mapping map are as follows: triggering the generation and propagation of shear waves; measuring multiple elastic feature parameters at each sampling point in the region of interest, including longitudinal depth, transverse length and thickness; post-processing the corresponding elastic feature parameters measured at each sampling point; and constructing a three-dimensional elastic mapping map by interpolation, fitting and other mathematical processing methods using the processed elastic feature parameters.

S300B, Fusion and Display Steps: The elastic mapping map containing three-dimensional elastic distribution data is superimposed and fused to the B-mode ultrasound image and displayed synchronously.

Figure 8 illustrates a specific embodiment for acquiring a three-dimensional elastic distribution. The region of interest (ROI) 701 is established as a three-dimensional spatial coordinate system. The ROI 701 space has three directional axes: longitudinal depth N, lateral length M, and thickness L. Within the ROI 701 space, along the thickness L direction, there are several two-dimensional ROI planes 501, containing several sampling points: _X111 , _X121 , _X123 , ..., _Xnml (n = 1, 2, 3, ..., n>=1; m = 1, 2, 3, ..., m>=1; l = 1, 2, 3, ..., l>=1). Thickness L refers to an independent directional dimension that is not parallel to the longitudinal depth N and lateral length M. Data sampling along the thickness L direction can be achieved using two types of ultrasonic probes 208. The first type uses linear array probes, phased array probes, or convex array probes with transducer elements arranged in the same plane, implemented in the following two specific ways. The first method is multi-point detection within the intercostal spaces: the probe 20 is moved along the thickness L direction within a selected intercostal space, from left to right or from right to left, and a set of the above-mentioned two-dimensional measurements are performed sequentially on different spatial sections of the liver parenchyma; the second method is multi-point detection between intercostal spaces: the probe 20 is moved from top to bottom or from bottom to top to the next adjacent intercostal space, and a set of the above-mentioned two-dimensional measurements are performed sequentially on different spatial sections of the liver parenchyma; please note that the scope of protection of this invention does not limit the specific number of detections within each group, and should be understood as at least >2 times/group, with more being preferred.

The second scenario involves using a two-dimensional matrix probe, which is placed statically within the intercostal space of a specific area to collect three-dimensional data over a smaller area. Generally, the thickness L direction refers to the arrangement of the transducer elements along the width direction. Alternatively, the aforementioned multi-point detection method can be used to collect three-dimensional data over a larger area.

Synthesis of three-dimensional data: A typical application is to provide a reconstruction unit 32c for images and elastic parameters, and synthesize two-dimensional elastic maps into three-dimensional elastic maps through mathematical processing methods such as interpolation and fitting; thereby vividly illustrating the distribution of elastic features in three-dimensional space.

Furthermore, to generate directional ultra-high frame rate ultrasonic signals and execute the above sampling mode, the present invention can be implemented by two technical solutions: Based on the coordinate position of the target sampling point, the time delay (delay) for transmitting and receiving ultrasonic waves by the corresponding transducer array element is calculated. a) Single-dimensional measurement: By exciting a single array element, a radio frequency (RF) signal is obtained; based on the RF signal and controlling the time delay, sampling at the longitudinal detection depth is achieved. b) Multi-dimensional spatial measurement: Simultaneously or with mutual delay, different array elements are controlled in parallel to obtain radio frequency (RF) signals; based on the RF signal and controlling the time delay, sampling in two-dimensional space (i.e., longitudinal depth and lateral length) or three-dimensional space is completed; This enables the measurement of multiple elastic characteristic parameters within a certain imaging section at the same body surface detection point.

This invention also provides a computer-readable storage medium, in which a computer program is stored in storage unit 33, including software execution code and algorithm program. During the process of performing dimensional biological tissue elasticity detection, when the software execution code and algorithm program are executed by a processor, the processor performs one-dimensional, two-dimensional, and three-dimensional ultrasound instantaneous elasticity detection steps: acquiring a two-dimensional ultrasound image; determining the location of a region of interest (ROI) on the two-dimensional ultrasound image; establishing a corresponding dimension sampling coordinate system within the ROI; determining the number and coordinate positions of sampling points within the selected corresponding dimension sampling coordinate system; measuring at least one elastic feature parameter at each selected sampling point within the corresponding ROI using a probe; mapping and processing the corresponding elastic feature parameters measured at each sampling point to construct an elasticity mapping map of the corresponding dimension sampling coordinate system; and superimposing and fusing the corresponding dimension elasticity mapping map onto the two-dimensional ultrasound image and displaying it synchronously. The process involves triggering the probe to emit a directional, ultra-high frame rate ultrasonic signal to track shear waves for sampling. Before sampling, the time delay between the transmission and reception of ultrasonic waves by the corresponding transducer element of the probe is calculated. The sampling modes include: obtaining a radio frequency (RF) signal by exciting a single element of the probe and calculating the elastic characteristic parameters at a specified location in a single-dimensional space; or obtaining a radio frequency (RF) signal by controlling different elements of the probe in parallel and calculating the elastic characteristic parameters at a specified location in a multi-dimensional space.

It should be noted that the methods, systems, and storage media for detecting the elasticity of biological tissues with dimensionality belong to the same inventive concept. Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and/or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), Dual Data Rate SDRAM (DDRSDRAM), Enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus Direct RAM (RDRAM), Direct Memory Bus Dynamic RAM (DRDRAM), and Memory Bus Dynamic RAM (RDRAM), etc. The sequence numbers of the above embodiments are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

In summary, this invention utilizes an ultrasonic transducer to emit ultrasonic waves and receive the echo signals reflected from the liver to obtain an ultrasonic image of the liver and establish a coordinate system for sampling regions of interest, determining the number and coordinate distribution of sampling points. It employs an ultrasonic probe formed by arranging several ultrasonic piezoelectric transducer elements in a linear array, convex array, or two-dimensional array to achieve dimensional elastic measurement, enabling rapid and accurate acquisition of one-dimensional, two-dimensional, and three-dimensional liver elastic distribution states, thus improving examination efficiency and increasing the reliability of results. Especially for one-dimensional and two-dimensional elasticity measurements, this invention eliminates the need for manual probe movement. A single detection at a specific point enables multiple sampling (i.e., simultaneous measurement of multiple elasticity characteristic parameters), and synthesizes a single-valued or color-coded elasticity mapping distribution map. This overcomes the limitations of existing single-valued instantaneous elasticity measurement techniques, which can only perform single sampling and cannot obtain spatial distribution information. This invention achieves its objectives of saving time, improving inspection efficiency, minimizing system errors by increasing sample size, improving the reliability of results, and reducing sampling errors. Furthermore, the adjustable and switchable sampling point distribution mode of this invention can selectively avoid large blood vessels and the bile duct system to obtain the distribution of liver biological parameters, making the results more accurate and customizable.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims (7)

1. A dimensional elasticity detection method for detecting biological tissues, characterized in that the method comprises the following steps: Acquire ultrasound images of the target object; In response to external vibration excitation, the elastic characteristic parameters of the target object at specified coordinate positions are collected and mapped to generate an elastic mapping diagram; the specific steps include: Based on the ultrasound image, a coordinate system for sampling the region of interest is established, and the number of sampling points and their coordinate distribution are determined. The region of interest is located within the selected ultrasound image and is either a two-dimensional plane or a three-dimensional space coordinate system. Based on the coordinate system dimension and position of the selected region of interest, the sampling points are specific coordinate points located in the coordinate system and distributed according to specific positions. The elastic characteristic parameters of the target object sampling points are measured by: applying low-frequency mechanical vibration to the body surface to generate shear waves that propagate inside the biological tissue; controlling the corresponding array elements in the ultrasonic transducer array to transmit and receive ultra-high frame rate ultrasonic waves to track the shear waves along the specified coordinate positions or different directions of each sampling point, and simultaneously or with delays, performing parameter measurements on multiple sampling points. Generate elasticity mapping map: Using mapping technology, the elasticity feature parameters at specified coordinate locations are encoded into a single-value mapping map or a color mapping map to characterize the distribution state of elasticity features; The probe is triggered to emit a directional, ultra-high frame rate ultrasonic signal to track shear waves in order to perform sampling; The sampling mode includes: obtaining radio frequency (RF) signals by controlling different array elements of the probe in parallel, and calculating elastic characteristic parameters at a specified location in multidimensional space; The external vibration excitation is applied continuously at a certain repetition frequency, and the ultra-high frame rate ultrasound will simultaneously track the propagation of multiple shear waves generated in the biological tissue by continuous vibration. The elastic mapping map containing elastic distribution data is superimposed and fused into the ultrasound image and displayed synchronously. 2. The detection method according to claim 1, characterized in that, The elastic characteristic parameters are parameters related to the elasticity of biological tissues, including elastic parameters, ultrasound parameters, and two-dimensional ultrasound image characteristic parameters; the elastic parameters are expressed by Young's modulus. 3. The detection method according to claim 2, characterized in that the time delay of ultrasonic wave transmission and reception by the transducer array element corresponding to the probe is calculated before sampling. 4. The detection method according to claim 1, characterized in that the three-dimensional data acquisition is achieved by using a two-dimensional array probe fixedly placed at a single detection point on the body surface for single-point detection; or by using a linear array probe, phased array probe, or convex array probe to move on multiple detection points on the body surface for multi-point detection. 5. The detection method according to claim 1, wherein the acquisition of the ultra-high frame rate ultrasound is performed simultaneously at at least two positions or directions. 6. A dimensional elastic detection system for detecting biological tissues, comprising an image acquisition unit for acquiring ultrasound images of a target object and a probe for transmitting and receiving ultrasound signals; characterized in that the detection system further comprises: The main control unit is connected to the image acquisition unit and the probe, respectively. It is used to establish a coordinate system of the corresponding dimension of the sampling region of interest based on the acquired ultrasound image of the target object, and determine the number and coordinate distribution of sampling points; it receives the elastic feature parameters of the region of interest corresponding to the target object, maps and generates an elastic mapping map, and superimposes and fuses the elastic mapping map containing elastic distribution data onto the ultrasound image and displays it synchronously. The probe includes an ultrasonic probe and a low-frequency vibrator coupled to the ultrasonic probe. The ultrasonic probe consists of several ultrasonic piezoelectric transducer elements arranged in a linear array, convex array, or two-dimensional array. The low-frequency vibrator continuously applies mechanical vibration to the body surface at a certain repetition frequency, generating multiple shear waves that propagate inside biological tissues by continuous vibration. The main control unit includes a control unit and a processing unit. The control unit is connected to the image acquisition unit, the probe, and the processing unit, respectively. The control unit is used to receive ultrasound images from the image acquisition unit and transmit the ultrasound images to the processing unit. The processing unit is used to determine the distribution coordinates of sampling points in the region of interest based on the ultrasound images and transmit the distribution coordinate information of the sampling points to the control unit. The control unit is also configured to control the low-frequency vibrator to send shear waves to the target object according to the sampling point distribution coordinates, and the ultrasonic transducer array element of the probe to send ultra-high frame rate ultrasonic signals to the sampling point distribution coordinates, receive the radio frequency (RF) signals fed back from the sampling point distribution coordinates, and transfer the RF signals and their distribution data acquired by the probe to the processing unit. The processing unit is also used to calculate the corresponding elastic characteristic parameters based on the received RF signals and their distribution data of each coordinate, establish an elastic mapping map of a one-dimensional or multi-dimensional state, and fuse the corresponding mapping map with the ultrasound image. The fused image is displayed synchronously through a display unit connected to the processing unit. 7. A computer-readable storage medium, characterized in that it stores a computer program, which, when executed by a CPU within a main control unit, implements the steps of the detection method as described in any one of claims 1 to 5.