Three-dimensional ultrasonic positioning imaging method and three-dimensional ultrasonic imaging scanning equipment

Abstract

The invention provides a three-dimensional ultrasonic positioning imaging method and three-dimensional ultrasonic imaging scanning device.The three-dimensional ultrasonic positioning imaging method comprises the steps that a two-dimensional linear array ultrasonic transducer is used for obtaining an ultrasonic image of a corresponding two-dimensional section of an object to be scanned in real time in the motion scanning process; the relative displacement between the two-dimensional linear array ultrasonic transducer and the outer surface area of the corresponding to-be-scanned object in the motion scanning process and the space deflection of the outer surface area of the corresponding to-be-scanned object are obtained in real time, so that the space track of the two-dimensional linear array ultrasonic transducer in the motion scanning process is obtained; and obtaining a three-dimensional ultrasonic imaging result of the to-be-scanned object. According to the three-dimensional ultrasonic positioning imaging method, the positioning precision of the space track of the two-dimensional linear array ultrasonic transducer is high, positioning can be achieved through the relative displacement between the three-dimensional ultrasonic imaging scanning equipment and the outer surface area of the object to be scanned, an external additional magnetic field or optical monitoring is not needed, and therefore electromagnetic interference can be effectively avoided.

Description

Technical Field

[0001] This application relates to the field of biomedical imaging, specifically to a three-dimensional ultrasound positioning imaging method and a three-dimensional ultrasound imaging scanning device. Background Technology

[0002] Ultrasound imaging, as a mature medical imaging method, has become a widely used two-dimensional medical imaging tool in clinical practice due to its advantages such as being non-invasive, radiation-free, providing real-time dynamic imaging, low cost, and portability. Current two-dimensional ultrasound mainly acquires grayscale images of a single cross-section using linear or phased array transducers, and has already achieved highly mature clinical applications in fields such as cardiology, abdominal surgery, obstetrics and gynecology, and superficial organs.

[0003] Two-dimensional ultrasound has significant limitations: it can only provide local sectional information, and the imaging path depends on the operator's real-time control, making it unable to intuitively and accurately display the spatial morphology of complex anatomical structures. This deficiency limits the application of two-dimensional ultrasound in clinical scenarios such as intraoperative navigation, tumor spatial assessment, and organ volume measurement.

[0004] To overcome the limitations of two-dimensional imaging in representing spatial information, three-dimensional ultrasound technology has emerged. Some research teams have developed three-dimensional ultrasound imaging scanning devices, such as fixed imaging systems based on hemispherical linear array transducers or ring scanning mechanisms, which acquire three-dimensional ultrasound data using spherical or toroidal ultrasound transducers. Although such systems have made breakthroughs in image signal-to-noise ratio and real-time performance, they still face many problems in practical applications, including large device size, complex mechanical structure, high system cost, poor operational flexibility, and weak patient adaptability. These problems severely limit their widespread clinical application.

[0005] To address the need for portable 3D imaging, freehand scanning 3D ultrasound imaging technology based on electromagnetic sensors has emerged in recent years. This technology uses electromagnetic sensors to track the spatial position of the transducer in real time, stitching together continuous 2D images into a 3D volumetric image. However, electromagnetic tracking systems have the following serious drawbacks: the electromagnetic field is easily interfered with by metallic objects, resulting in poor stability in environments such as operating rooms; the scanning space is limited, making it difficult to achieve large-area free scanning, etc.

[0006] Therefore, there is still a lack of a high-precision, non-external monitoring, fast, and wide-range free-scanning three-dimensional ultrasound imaging scanning device. Summary of the Invention

[0007] In view of this, the embodiments of this application aim to provide a three-dimensional ultrasound positioning and imaging method and a three-dimensional ultrasound imaging scanning device to solve the technical problems of poor accuracy, the need for external monitoring, and the unsuitability for large-area free scanning of existing three-dimensional ultrasound positioning and imaging methods.

[0008] The first aspect of this application provides a three-dimensional ultrasound imaging scanning device for performing three-dimensional ultrasound imaging of an object to be scanned, and includes: During motion scanning, a two-dimensional linear array ultrasonic transducer is used to acquire ultrasonic images of the corresponding two-dimensional cross-section of the object to be scanned in real time. The spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning is obtained, wherein the spatial trajectory includes spatial displacement and spatial attitude change; Based on the ultrasonic image of the corresponding two-dimensional cross section of the object to be scanned, which is acquired in real time during the motion scanning process by the two-dimensional linear array ultrasonic transducer, and the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process, the three-dimensional ultrasonic imaging result of the object to be scanned is obtained. The step of obtaining the spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning includes: Real-time acquisition of the relative displacement between the two-dimensional linear array ultrasonic transducer and the corresponding outer surface region of the object to be scanned during motion scanning; During the motion scanning process, the two-dimensional linear array ultrasonic transducer acquires the spatial deflection of the outer surface region of the object to be scanned in real time. Based on the relative displacement between the two-dimensional linear array ultrasonic transducer and the corresponding outer surface region of the object to be scanned during the motion scanning process, and the spatial deflection of the two-dimensional linear array ultrasonic transducer corresponding to the outer surface region of the object to be scanned, the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process is obtained.

[0009] In one embodiment of this application, the step of acquiring the spatial deflection of the outer surface region of the object to be scanned in real time during the motion scanning process of the two-dimensional linear array ultrasonic transducer includes: The absolute spatial orientation of the two-dimensional linear array ultrasonic transducer relative to the reference direction is acquired in real time during the motion scanning process. Real-time acquisition of the relative spatial deflection of the two-dimensional linear array ultrasonic transducer to the outer surface region of the object to be scanned during motion scanning; By utilizing the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer relative to the reference direction during motion scanning, and the relative spatial deflection of the two-dimensional linear array ultrasonic transducer corresponding to the outer surface region of the object to be scanned during motion scanning, the spatial deflection of the outer surface region of the object to be scanned is obtained in real time.

[0010] In one embodiment of this application, the step of acquiring the relative spatial deflection of the two-dimensional linear array ultrasonic transducer to the outer surface region of the object to be scanned during motion scanning in real time includes: At least two ranging sensors are used to acquire the absolute distance between the outer surface region of the corresponding object to be scanned along the corresponding ranging direction in real time, wherein each of the ranging sensors is fixed relative to the two-dimensional linear array ultrasonic transducer. By using the absolute distances between the two-dimensional linear array ultrasonic transducer and the outer surface region of the object to be scanned along the corresponding ranging direction, which are obtained in real time by each of the ranging sensors, the relative spatial deflection of the two-dimensional linear array ultrasonic transducer relative to the outer surface region of the object to be scanned during the motion scanning process is obtained in real time.

[0011] In one embodiment of this application, the step of acquiring the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer relative to a reference direction in real time during motion scanning includes: An inertial measurement unit equipped with a three-axis gyroscope and a three-axis accelerometer is used to acquire the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer relative to the reference direction in real time during the motion scanning process, wherein the inertial measurement unit is relatively fixed to the two-dimensional linear array ultrasonic transducer.

[0012] In one embodiment of this application, the step of acquiring the relative displacement between the two-dimensional linear array ultrasonic transducer and the corresponding outer surface region of the object to be scanned in real time during motion scanning includes: An optical flow sensor is used to acquire images of the outer surface region of the object to be scanned in real time. Based on the inter-frame pixel grayscale changes of the images of the outer surface region of the object to be scanned, the relative displacement between the two-dimensional linear ultrasonic transducer and the outer surface region of the object to be scanned during the motion scanning process is acquired in real time. The optical flow sensor and the two-dimensional linear ultrasonic transducer are relatively fixed.

[0013] In one embodiment of this application, the step of obtaining the spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning further includes: During motion scanning, a two-dimensional linear array ultrasonic transducer is used to acquire ultrasonic images of the corresponding two-dimensional cross-section of the object to be scanned in real time. The spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning is then corrected to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning.

[0014] In one embodiment of this application, the step of acquiring ultrasound images of the corresponding two-dimensional cross-section of the object to be scanned in real time during motion scanning using a two-dimensional linear array ultrasonic transducer, and correcting the spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning includes: Obtain the spatial trajectory segment to be corrected in the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process; Obtain the feature points in the ultrasound image corresponding to the spatial trajectory segment to be corrected, and the feature identifiers of the feature points; Using the ultrasound images with the aforementioned feature points and the feature identifiers of the feature points, the estimated trajectory change between the ultrasound images is obtained; By utilizing the spatial estimated trajectory change between each ultrasound image obtained in the spatial trajectory of the two-dimensional linear array ultrasound transducer during motion scanning, and the image estimated trajectory change between each ultrasound image, the fusion estimated trajectory change between each ultrasound image is obtained, thereby obtaining the fused spatial trajectory of the two-dimensional linear array ultrasound transducer during motion scanning.

[0015] In one embodiment of this application, the step of acquiring ultrasound images of the corresponding two-dimensional cross-section of the object to be scanned in real time during motion scanning using a two-dimensional linear array ultrasonic transducer, and correcting the spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning further includes: The fused spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning is processed by at least one of trajectory smoothing, Kalman filter dynamic optimization, and motion physical constraint verification to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer during motion scanning.

[0016] In one embodiment of this application, the step of obtaining the three-dimensional ultrasound imaging result of the object to be scanned based on the ultrasound image of the corresponding two-dimensional cross-section of the object to be scanned acquired in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer, and the spatial trajectory of the two-dimensional linear array ultrasound transducer during the motion scanning process includes: Based on the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process, the three-dimensional spatial transformation matrix of each ultrasonic image is obtained. Using the three-dimensional spatial transformation matrix of each ultrasound image, all pixels of each ultrasound image are mapped to a voxel grid in three-dimensional space; The grayscale mean of each pixel in a voxel grid within a three-dimensional space is obtained to obtain the three-dimensional ultrasound imaging result of the object to be scanned.

[0017] Another aspect of this application provides a three-dimensional ultrasound imaging scanning device for performing three-dimensional ultrasound imaging on an object to be scanned, and includes a handheld component and a processing control unit. The handheld assembly includes a two-dimensional linear array ultrasonic transducer, an optical flow sensor, an inertial measurement unit, and at least two ranging sensors; The two-dimensional linear array ultrasonic transducer is configured to acquire ultrasonic images of the corresponding two-dimensional cross-section of the object to be scanned in real time during motion scanning. The inertial measurement unit is equipped with a three-axis gyroscope and a three-axis accelerometer, and is configured to use the three-axis gyroscope and the three-axis accelerometer to acquire in real time the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer relative to the reference direction during motion scanning; The optical flow sensor is configured to acquire images of the outer surface region of the object to be scanned in real time, and based on the inter-frame pixel grayscale changes of the images of the outer surface region of the object to be scanned, acquire the relative displacement between the two-dimensional linear ultrasonic transducer and the outer surface region of the object to be scanned in real time during the motion scanning process. Each of the ranging sensors is configured to acquire, in real time, the absolute distance between itself and the outer surface region of the corresponding object to be scanned along the corresponding ranging direction; The processing control unit is connected to the two-dimensional linear array ultrasonic transducer, optical flow sensor, inertial measurement unit and at least two ranging sensors, and is configured to acquire the three-dimensional ultrasonic imaging results of the object to be scanned based on the output signals of the two-dimensional linear array ultrasonic transducer, optical flow sensor, inertial measurement unit and at least two ranging sensors.

[0018] During the motion scanning process of the two-dimensional linear array ultrasonic transducer in this embodiment, the two-dimensional linear array ultrasonic transducer moves along the surface of the object to be scanned, generating corresponding ultrasonic images of two-dimensional cross-sections at different positions of the object in real time. To perform three-dimensional ultrasonic imaging, it is also necessary to acquire the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process. After obtaining the ultrasonic images of the corresponding two-dimensional cross-sections of the object to be scanned acquired in real time during the motion scanning process, and the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process, the three-dimensional ultrasonic imaging result of the object to be scanned can be obtained based on these two-dimensional ultrasonic images of the object to be scanned acquired in real time during the motion scanning process, and the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process.

[0019] In the three-dimensional ultrasonic positioning imaging method of this application embodiment, in order to obtain the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process, the relative displacement between the two-dimensional linear array ultrasonic transducer and the outer surface region of the corresponding object to be scanned can be obtained in real time during the motion scanning process of the two-dimensional linear array ultrasonic transducer. Furthermore, the spatial deflection of the outer surface region of the corresponding object to be scanned can be obtained in real time during the motion scanning process of the two-dimensional linear array ultrasonic transducer. Then, the spatial trajectory of the two-dimensional linear array ultrasonic transducer during the motion scanning process can be obtained based on the relative displacement between the two-dimensional linear array ultrasonic transducer and the outer surface region of the corresponding object to be scanned during the motion scanning process, and the spatial deflection of the two-dimensional linear array ultrasonic transducer and the outer surface region of the corresponding object to be scanned during the motion scanning process.

[0020] Compared to existing three-dimensional ultrasound imaging technologies based on electromagnetic sensors, the three-dimensional ultrasound positioning imaging method of this application does not rely on electromagnetic sensors to track the spatial trajectory of a two-dimensional linear ultrasound transducer in real time. Instead, it obtains the spatial trajectory of the two-dimensional linear ultrasound transducer during motion scanning by measuring the relative displacement between the two-dimensional linear ultrasound transducer and the corresponding outer surface area of ​​the object to be scanned, and the spatial deflection of the two-dimensional linear ultrasound transducer relative to the outer surface area of ​​the object to be scanned. This method not only has high positioning accuracy for the spatial trajectory of the two-dimensional linear ultrasound transducer, but also achieves positioning through the relative displacement between the three-dimensional ultrasound imaging scanning device and the outer surface area of ​​the object to be scanned. It does not require external magnetic fields or optical monitoring, thus effectively avoiding electromagnetic interference and being suitable for large-scale free scanning, thereby adapting to various clinical environments. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the three-dimensional ultrasound imaging scanning device of this application.

[0022] Figure 2 This is a partial structural schematic diagram of the three-dimensional ultrasound imaging scanning device of this application.

[0023] Figure 3 This is a schematic diagram illustrating the steps of the three-dimensional ultrasound positioning and imaging method of this application.

[0024] Figure 4 This is a schematic diagram of some steps of the three-dimensional ultrasound positioning and imaging method of this application.

[0025] Figure 5 This is a schematic diagram of some steps of the three-dimensional ultrasound positioning and imaging method of this application.

[0026] Figure 6 This is a schematic diagram of some steps of the three-dimensional ultrasound positioning and imaging method of this application.

[0027] Figure 7This is a schematic diagram of some steps of the three-dimensional ultrasound positioning and imaging method of this application.

[0028] Figure 8 This is a schematic diagram of the results of the three-dimensional ultrasound positioning imaging method of this application.

[0029] Attached image labels: 1. Inertial measurement unit; 2. Two-dimensional linear array ultrasonic transducer; 3. Distance sensor; 4. Optical flow sensor; 5. Housing. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of this application. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0032] Many specific details are set forth in the following description to provide a full understanding of this application. However, this application can be implemented in many other ways than those described herein, and those skilled in the art can make similar extensions without departing from the spirit of this application; therefore, this application is not limited to the specific embodiments disclosed below. Techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and apparatus should be considered part of the specification.

[0033] The terminology used in one or more embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of this application. The singular forms “a,” “the,” and “the” used in one or more embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” used in one or more embodiments of this application refers to and includes any or all possible combinations of one or more associated listed items.

[0034] It should be understood that although the terms first, second, etc., may be used to describe various information in one or more embodiments of this application, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first may also be referred to as second without departing from the scope of one or more embodiments of this application, and similarly, second may also be referred to as first. Depending on the context, the word “if” as used herein may be interpreted as “when”, “in response to a determination”, or “upper”, “lower”, “front”, “back”, “left”, “right”, etc., are used only to indicate the relative positional relationship between related parts, and not to limit the absolute position of these related parts. In this document, “equal”, “same”, etc., are not strict mathematical and / or geometric limitations, and also include errors that are understandable to those skilled in the art and permissible in manufacturing or use. Unless otherwise stated, numerical ranges in this document include not only the entire range within its two endpoints, but also several sub-ranges contained therein.

[0035] This application provides a three-dimensional ultrasound positioning and imaging method for performing three-dimensional ultrasound imaging on an object to be scanned. Specifically, the three-dimensional ultrasound positioning and imaging method of this application is applied... Figure 1 and Figure 2 The three-dimensional ultrasound imaging scanning device shown in the figure performs three-dimensional ultrasound imaging of the object to be scanned.

[0036] like Figure 3 As shown, the three-dimensional ultrasound localization imaging method of this application includes: S1: During motion scanning, the ultrasonic image of the corresponding two-dimensional cross-section of the object to be scanned is acquired in real time using the two-dimensional linear array ultrasonic transducer 2.

[0037] S2: Obtain the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process.

[0038] Spatial trajectory includes spatial displacement and changes in spatial attitude.

[0039] S3: Based on the ultrasonic image of the corresponding two-dimensional cross section of the object to be scanned, which is acquired in real time during the motion scanning process by the two-dimensional linear array ultrasonic transducer 2, and the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process, the three-dimensional ultrasonic imaging result of the object to be scanned is obtained.

[0040] Therefore, in the three-dimensional ultrasound positioning and imaging method of this application embodiment, after the two-dimensional linear array ultrasound transducer 2 is turned on, by moving the two-dimensional linear array ultrasound transducer 2, the two-dimensional linear array ultrasound transducer 2 can scan during the movement process. During the movement scanning process, the two-dimensional linear array ultrasound transducer 2 can acquire the ultrasound image of the corresponding two-dimensional cross section of the object to be scanned in real time.

[0041] Specifically, the two-dimensional linear array ultrasonic transducer 2 can acquire two-dimensional images of the internal structure of an object by emitting and receiving ultrasonic signals. The two-dimensional linear array ultrasonic transducer 2 consists of multiple ultrasonic transducers arranged in a row. Each transducer can both emit ultrasonic waves and receive reflected ultrasonic signals. During scanning, each transducer in the linear array emits ultrasonic pulses sequentially or in groups. The ultrasonic pulses are emitted at a certain frequency. The emitted ultrasonic waves propagate in the object being scanned and are reflected, refracted, or scattered when they encounter interfaces with different densities or acoustic impedances. The two-dimensional linear array ultrasonic transducer 2 receives these reflected signals. It is understood that there is a time delay in the reflected signals, which is proportional to the distance to the reflection point. Therefore, by measuring the time delay, the depth of the reflection point can be calculated. By synthesizing the ultrasonic signals received by each transducer, the direction, distance, and intensity of the reflected signals are determined. Based on the direction, distance, and intensity of the reflected signals, the position and reflection intensity of each reflection point are calculated, thereby generating a two-dimensional cross-sectional image.

[0042] Therefore, during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2 in this embodiment, the two-dimensional linear array ultrasonic transducer 2 moves along the surface of the object to be scanned, generating corresponding ultrasonic images of two-dimensional cross-sections at different positions of the object in real time. Specifically, in one embodiment of this application, the center frequency of the two-dimensional linear array ultrasonic transducer 2 can be 10MHz, and the frame rate of acquiring ultrasonic images can reach 120 frames per second.

[0043] by Figure 2 With the center direction as the reference, the two-dimensional linear array ultrasonic transducer 2 of this application embodiment acquires in real time the ultrasonic image of the corresponding two-dimensional cross section of the object to be scanned, which is the ultrasonic image of the corresponding two-dimensional cross section in the XZ direction.

[0044] Understandably, in order to perform three-dimensional ultrasound imaging, it is also necessary to obtain the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process. The spatial trajectory includes spatial displacement and spatial attitude change. Spatial displacement is the position change of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process, and spatial attitude change is the attitude change of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process.

[0045] Then, after obtaining the ultrasound image of the corresponding two-dimensional cross-section of the object to be scanned in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer 2, and the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process, the three-dimensional ultrasound imaging result of the object to be scanned can be obtained based on the ultrasound image of the corresponding two-dimensional cross-section of the object to be scanned in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer 2, and the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process.

[0046] Among them, such as Figure 4 As shown, in the three-dimensional ultrasound positioning imaging method of this application embodiment, step S2: acquiring the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during motion scanning includes: S21: Real-time acquisition of the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned during motion scanning.

[0047] S22: During the motion scanning process of the two-dimensional linear array ultrasonic transducer 2, the spatial deflection of the corresponding outer surface region of the object to be scanned is acquired in real time.

[0048] S23: Based on the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the corresponding outer surface region of the object to be scanned during the motion scanning process, and the spatial deflection of the two-dimensional linear array ultrasonic transducer 2 corresponding to the outer surface region of the object to be scanned during the motion scanning process, the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process is obtained.

[0049] In the three-dimensional ultrasound positioning imaging method of this application embodiment, in order to obtain the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process, the relative displacement between the two-dimensional linear array ultrasound transducer 2 and the corresponding outer surface region of the object to be scanned can be obtained in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer 2. Furthermore, the spatial deflection of the corresponding outer surface region of the object to be scanned can be obtained in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer 2. Then, based on the relative displacement between the two-dimensional linear array ultrasound transducer 2 and the corresponding outer surface region of the object to be scanned during the motion scanning process, and the spatial deflection of the two-dimensional linear array ultrasound transducer 2 and the corresponding outer surface region of the object to be scanned during the motion scanning process, the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process can be obtained.

[0050] Compared to existing three-dimensional ultrasound imaging technologies based on electromagnetic sensors, the three-dimensional ultrasound positioning imaging method of this application embodiment does not rely on electromagnetic sensors to track the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 in real time. Instead, it obtains the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process by measuring the relative displacement between the two-dimensional linear array ultrasound transducer 2 and the corresponding outer surface area of ​​the object to be scanned, and the spatial deflection of the two-dimensional linear array ultrasound transducer 2 corresponding to the outer surface area of ​​the object to be scanned. This method not only has high positioning accuracy for the spatial trajectory, but also achieves positioning through the relative displacement between the three-dimensional ultrasound imaging scanning device and the outer surface area of ​​the object to be scanned. It does not require external magnetic fields or optical monitoring, thus effectively avoiding electromagnetic interference and being suitable for large-scale free scanning, thereby adapting to various clinical environments.

[0051] It is understandable that the two-dimensional linear array ultrasonic transducer 2 has a detection direction during the motion scanning process, and this detection direction is... Figure 2In the negative Z-axis direction, along Figure 2 The negative Z-axis direction corresponds to a portion of the outer surface of the object to be scanned. This region is the outer surface region of the object to be scanned that the two-dimensional linear array ultrasonic transducer 2 corresponds to during the motion scanning process.

[0052] In one embodiment of this application, step S21: acquiring the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned during real-time motion scanning includes: The optical flow sensor 4 is used to acquire images of the outer surface region of the corresponding object to be scanned in real time. Based on the inter-frame pixel grayscale changes of the images of the outer surface region of the corresponding object to be scanned, the relative displacement between the two-dimensional linear ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned is acquired in real time during the motion scanning process. The optical flow sensor 4 and the two-dimensional linear ultrasonic transducer 2 are relatively fixed.

[0053] That is, during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2, the optical flow sensor 4 can simultaneously acquire images of the outer surface region of the corresponding object to be scanned in real time. Based on the inter-frame pixel grayscale changes of the images of the outer surface region of the corresponding object to be scanned, the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned during the motion scanning process is acquired in real time. This relative displacement includes relative displacements x(n) and y(n) in two directions. Specifically, as shown... Figure 1 As shown, there are two sets of optical flow sensors 4, and the distance between the two sets of optical flow sensors 4 is known. The displacement resolution of the optical flow sensor 4 can reach 100µm.

[0054] Understandably, since the outer surface of the object to be scanned is usually not planar, the detection direction of the two-dimensional linear ultrasonic transducer 2 cannot always remain perpendicular to the corresponding outer surface region of the object. The greater the tilt angle between the detection direction of the two-dimensional linear ultrasonic transducer 2 and the corresponding outer surface region of the object, the greater the relative displacement between the two-dimensional linear ultrasonic transducer 2 and the corresponding outer surface region of the object at the same distance. Therefore, it is necessary to obtain the spatial deflection between the detection direction of the two-dimensional linear ultrasonic transducer 2 and the corresponding outer surface region of the object to be scanned in order to correct the relative displacement between the two-dimensional linear ultrasonic transducer 2 and the corresponding outer surface region of the object during motion scanning.

[0055] Specifically, such as Figure 5 As shown, in one embodiment of this application, S22: the step of acquiring the spatial deflection of the outer surface region of the object to be scanned in real time during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2 includes: S221: Real-time acquisition of the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning.

[0056] It is understood that the aforementioned reference direction can be the direction of gravity or other reference directions, and there are no restrictions here.

[0057] Specifically, such as Figure 1 As shown, the three-dimensional ultrasonic imaging scanning device of this application embodiment may include an inertial measurement unit 1 fixed relative to the two-dimensional linear array ultrasonic transducer 2. The step of S221 above: acquiring the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning includes: using the inertial measurement unit 1 equipped with a three-axis gyroscope and a three-axis accelerometer to acquire the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning in real time.

[0058] Understandably, the steps of using an inertial measurement unit 1 equipped with a three-axis gyroscope and a three-axis accelerometer may include acquiring acceleration and angular velocity data using the three-axis accelerometer and the three-axis gyroscope respectively, calculating pitch and roll angles using acceleration data, calculating yaw angles using angular velocity integration, and then fusing the data to obtain a more accurate absolute spatial attitude.

[0059] For any given time in frame n, the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning can be determined by a rotation matrix. The calculation formula is as follows: in: ; ; .

[0060] S222: Real-time acquisition of the relative spatial deflection of the outer surface region of the object to be scanned by the two-dimensional linear array ultrasonic transducer 2 during motion scanning.

[0061] Understandably, during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2, the corresponding outer surface area of ​​the object to be scanned also moves. Not only will the two-dimensional linear array ultrasonic transducer 2 experience spatial deflection during motion scanning, but since the outer surface of the object to be scanned is usually not planar, the corresponding outer surface area of ​​the object to be scanned by the two-dimensional linear array ultrasonic transducer 2 will also experience spatial deflection.

[0062] Therefore, relevant equipment can be used to obtain the relative spatial deflection of the outer surface region of the object to be scanned during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2 in real time.

[0063] Specifically, such as Figure 1As shown, the three-dimensional ultrasonic imaging scanning device of this application embodiment may include at least two ranging sensors 3 that are fixed relative to the two-dimensional linear array ultrasonic transducer 2.

[0064] The above-mentioned step S222: Real-time acquisition of the relative spatial deflection of the outer surface region of the object to be scanned by the two-dimensional linear array ultrasonic transducer 2 during motion scanning includes: At least two ranging sensors 3 are used to acquire in real time the absolute distance between the corresponding ranging direction and the outer surface area of ​​the corresponding object to be scanned; By using the absolute distances between each ranging sensor 3 and the corresponding outer surface region of the object to be scanned along the corresponding ranging direction, the relative spatial deflection of the outer surface region of the object to be scanned by the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process is obtained in real time.

[0065] like Figure 2 As shown, in one embodiment of this application, the three-dimensional ultrasonic imaging scanning device is equipped with two ranging sensors 3; a three-dimensional coordinate axis is established with the two-dimensional linear array ultrasonic transducer 2 as the center, and the structural installation parameters of the two laser rangefinders relative to the transducer center are (a1,b1,c1) and (a2,b2,c2), respectively. The angles between the installation angles of the two laser rangefinders and the bottom surface of the three-dimensional ultrasonic imaging scanning device are p1 and p2, respectively. For ease of calculation, p1=p2=p. The absolute distances between the two laser rangefinders along the corresponding ranging direction and the corresponding outer surface area of ​​the object to be scanned are d1 and d2, respectively.

[0066] Therefore, taking the outer surface region of the object to be scanned as a reference, and considering that the tilt angle of the two-dimensional linear ultrasonic transducer 2 relative to the initial position on the X-axis is o1 and the tilt angle relative to the initial position on the Y-axis is o2 during the motion scanning process, then: The aforementioned o1 and o2 represent the relative spatial deflection of the two-dimensional linear array ultrasonic transducer 2 relative to the outer surface region of the object to be scanned during the motion scanning process. This reflects whether the two-dimensional linear array ultrasonic transducer 2 is in relative tilt deviation with the outer surface region of the object to be scanned. This tilt deviation is used to calculate the three-dimensional spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 in real time, ensuring that the spatial attitude of the two-dimensional linear array ultrasonic transducer 2 maintains an absolute reference relationship with the imaging plane.

[0067] S223: Utilizing the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning, and the relative spatial deflection of the two-dimensional linear array ultrasonic transducer 2 corresponding to the outer surface region of the object to be scanned during motion scanning, the spatial deflection of the outer surface region of the object to be scanned is obtained in real time.

[0068] It is understandable that by utilizing the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during the motion scanning process, and the relative spatial deflection of the outer surface region of the two-dimensional linear array ultrasonic transducer 2 corresponding to the object to be scanned during the motion scanning process, the spatial deflection of the outer surface region of the object to be scanned can be obtained in real time. This spatial deflection of the outer surface region of the object to be scanned is the spatial deflection of the outer surface region of the object to be scanned relative to the reference direction.

[0069] Therefore, by acquiring the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned during the motion scanning process in real time, and by acquiring the spatial deflection of the outer surface region of the corresponding object to be scanned during the motion scanning process of the two-dimensional linear array ultrasonic transducer 2, the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process can be obtained based on the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned during the motion scanning process, and the spatial deflection of the outer surface region of the two-dimensional linear array ultrasonic transducer 2 corresponding to the object to be scanned during the motion scanning process.

[0070] Specifically, as mentioned above, the absolute spatial orientation of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning can be represented by the rotation matrix R(device2ground); the relative spatial deflection of the two-dimensional linear array ultrasonic transducer 2 corresponding to the outer surface region of the object to be scanned during motion scanning can be represented by the rotation matrix R(device2plane); and the spatial deflection corresponding to the outer surface region of the object to be scanned can be represented by the rotation matrix R(plane2ground). Therefore, the following equations exist: R(plane2ground)= R(device2ground)·R(device2plane) -1 The relationship between R (device2plane) and the tilt angles of the two-dimensional linear ultrasonic transducer 2 relative to the initial position on the X-axis (o1) and Y-axis (o2) during the motion scanning process is as follows: , in: , .

[0071] Specifically, acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning can include: Optical flow sensor 4 is used to acquire the relative displacement between the two-dimensional linear ultrasonic transducer 2 and the outer surface region of the corresponding object being scanned during the motion scanning process in real time. The displacement difference between adjacent motion frames is obtained, and thus the incremental displacement of each motion frame is obtained. When two optical flow sensors 4 are set, the average incremental displacement of each motion frame can be obtained. ; Then, transform the average incremental displacement of each motion frame to the global coordinate system: d(n)= R(device2ground)(n)·ΔP(n); Then, the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process can be obtained by cumulative calculation: P(n) = P(n-1) + d(n); Where, P(n): the absolute position of the device in the global space at the nth frame; d(n): Spatial displacement increment of the current frame.

[0072] like Figure 4 As shown, in one embodiment of this application, step S2: acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning further includes: S24: During the motion scanning process, the ultrasonic image of the corresponding two-dimensional cross section of the object to be scanned is acquired in real time using the two-dimensional linear array ultrasonic transducer 2. The spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process is corrected to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process.

[0073] The three-dimensional ultrasound positioning imaging method of this application embodiment can use the two-dimensional linear array ultrasound transducer 2 to acquire the ultrasound image of the corresponding two-dimensional cross section of the object to be scanned in real time during the motion scanning process, and correct the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process. That is, the spatial trajectory is corrected in reverse based on the ultrasound image, thereby further improving the robustness and accuracy of the spatial trajectory calculation.

[0074] Specifically, such as Figure 6 As shown, in one embodiment of this application, S24: using the two-dimensional linear array ultrasonic transducer 2 to acquire the ultrasonic image of the corresponding two-dimensional cross-section of the object to be scanned in real time during the motion scanning process, and correcting the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process includes: S241: Obtain the spatial trajectory segment to be corrected in the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process.

[0075] The space trajectory segment to be corrected is the part of the space trajectory that needs to be corrected, and the space trajectory segment to be corrected can be selected as needed.

[0076] It can be understood that due to the minimum detection displacement threshold of the optical flow sensor 4, when the device movement speed of the two-dimensional linear array ultrasonic transducer 2 is too low or the outer surface texture of the object to be scanned is insufficient, the spatial displacements output by the optical flow sensor 4 in multiple consecutive frames are nearly zero, and it is easy to generate a motion trajectory dead zone.

[0077] Specifically, the spatial displacement data continuously output by the optical flow sensor 4 can be monitored in real time. When multiple consecutive frames satisfy Δd(n) < d(min), where d(min) is the minimum detection displacement threshold, it can be determined that this part of the space trajectory segment is a motion trajectory dead zone and needs to be corrected, that is, the motion trajectory dead zone is used as the space trajectory segment to be corrected.

[0078] In the prior art, the trajectory dead zone usually uses the linear interpolation method for data fitting, that is, in the motion dead zone segment, a straight line between the known trajectory points before and after is directly used as the estimation of the missing path. However, linear interpolation has the following deficiencies: it cannot truly reflect the actual motion mode of the two-dimensional linear array ultrasonic transducer 2 in the dead zone segment, ignores the possible complex motion trends of the two-dimensional linear array ultrasonic transducer 2, the interpolation path is prone to spatial offset, the cumulative error is obvious, the interpolation result completely depends on adjacent valid frames, and the image information of the current frame cannot be used for correction.

[0079] Therefore, the three-dimensional ultrasonic positioning imaging method of the embodiment of the present application uses the ultrasonic image corresponding to the space trajectory segment to be corrected to correct the space trajectory segment to be corrected. The specific steps are as follows.

[0080] S242: Obtain the feature points and the feature identifiers of the feature points in the ultrasonic image corresponding to the space trajectory segment to be corrected.

[0081] By obtaining the feature points and the feature identifiers of the feature points in the ultrasonic image corresponding to the space trajectory segment to be corrected, it is convenient to subsequently obtain the image estimated trajectory change amount between each ultrasonic image by using each ultrasonic image with feature points and the feature identifiers of the feature points.

[0082] It can be understood that before obtaining the feature points and the feature identifiers of the feature points in the ultrasonic image corresponding to the space trajectory segment to be corrected, the ultrasonic image corresponding to the space trajectory segment to be corrected is preprocessed by means such as histogram equalization, Gaussian filtering for noise reduction, image sharpening, gray normalization, and image boundary enhancement, so as to improve the overall contrast of the image, enhance the gray difference of the ultrasonic image, effectively suppress the high-frequency noise of the image, eliminate the gray deviation between different image frames, and facilitate the subsequent extraction of feature points. The principle will not be elaborated here.

[0083] Specifically, when obtaining the feature points in the ultrasound image corresponding to the spatial trajectory segment to be corrected, the SURF algorithm can be used for preliminary screening first, and then the Harris corner point algorithm can be used to finally determine the feature points in the ultrasound image.

[0084] When using the SURF algorithm for initial screening, the Hessian matrix of the ultrasound image at different scales can be calculated, and the determinant of the Hessian matrix can be used: Pixels in the ultrasound image whose local response intensity exceeds a set threshold are selected as SURF candidate feature points. The second Gaussian derivative of the image in the X direction; The second Gaussian derivative of the image in the Y direction; : The mixed second-order Gaussian derivative of the image in the X and Y directions.

[0085] After obtaining the SURF candidate feature points, the autocorrelation matrix can be calculated for the neighboring image patches of the SURF candidate feature points: .in, and For the horizontal and vertical gradients of the image, The weighted window function is used; and the corner response functions of the SURF candidate feature points are calculated: , where k is an empirical coefficient.

[0086] Among them, SURF candidate feature points whose response value R exceeds the set threshold can be used as feature points in the ultrasound image corresponding to the spatial trajectory segment to be corrected.

[0087] After obtaining the feature points in the ultrasound image corresponding to the spatial trajectory segment to be corrected, the feature identifiers of the feature points can be calculated. The feature identifiers can uniquely identify the feature points.

[0088] Specifically, methods for calculating feature identifiers for feature points can include: (1) Neighborhood division A scale-adaptive square neighborhood region is constructed centered on the feature point coordinates, and the neighborhood is divided into 4×4 sub-regions.

[0089] (2) Local gradient statistics Within each sub-region, calculate the horizontal and vertical gradients for all pixels: , ; Accumulate for each sub-region separately: The feature statistics of the 16 sub-regions are then concatenated sequentially to form the final 64-dimensional feature descriptor: This feature identifier has rotation invariance, scale invariance, and good noise robustness, making it suitable for subsequent motion trajectory correction.

[0090] S243: Using each ultrasound image with feature points and the feature identifier of the feature points, obtain the estimated trajectory change between each ultrasound image.

[0091] Specifically, the RANSAC randomized controlled trial method can be used to obtain the changes in the estimated trajectory between various ultrasound images. RANSAC is used to eliminate mismatched points from the feature point matching pairs of ultrasound images and find the optimal motion estimation model. That is, from the feature point matching pairs of two adjacent frames of ultrasound images, the smallest sample point set is randomly selected, and the two-dimensional planar motion transformation matrix between the images is calculated. For all matching point pairs, the system calculates the projection error. Through multiple rounds of iterative sampling, the number of inliers in each round is recorded, and the motion model with the most inliers is selected as the optimal matching result. Based on this motion model, the changes in the estimated trajectory between various ultrasound images can be obtained.

[0092] S244: By acquiring the spatial estimated trajectory change between each ultrasound image and the image estimated trajectory change between each ultrasound image in the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process, the fusion estimated trajectory change between each ultrasound image is obtained, and then the fused spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process is obtained.

[0093] It is understandable that, based on the aforementioned spatial trajectory, the spatial estimated trajectory change between each ultrasound image can be obtained. Then, using the image estimated trajectory change between each ultrasound image, the fusion estimated trajectory change between each ultrasound image can be obtained, thereby obtaining the fused spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process.

[0094] Among them, the trajectory change between two adjacent frames in the fused spatial trajectory is in: The displacement change is based on the aforementioned spatial trajectory. It uses images obtained between ultrasound images to estimate the displacement change in trajectory changes. The attitude change is based on the aforementioned spatial trajectory. It uses images obtained from ultrasound images to estimate the attitude change in trajectory changes. For spatial trajectory corresponding fusion weights, Estimate the corresponding fusion weights for the image. Understandably, and The specific value can be selected as needed and is not restricted here.

[0095] After correcting the spatial trajectory, the final fused spatial trajectory attitude is obtained: ; .

[0096] It can be seen that the above-mentioned three-dimensional motion trajectory correction algorithm based on the fusion of multiple sensors and ultrasonic images can dynamically correct the spatial trajectory error of the two-dimensional linear array ultrasonic transducer 2 by fusing the spatial trajectory obtained by the sensors and the feature motion information obtained by the ultrasonic images. This effectively improves the motion tracking accuracy of the two-dimensional linear array ultrasonic transducer 2 and the consistency of three-dimensional ultrasonic reconstruction. It can effectively solve the problems of the dead zone of the optical flow sensor 4 and the insensitivity of the laser rangefinder to small angular deviations.

[0097] like Figure 6 As shown, in one embodiment of this application, the step of using a two-dimensional linear array ultrasonic transducer 2 to acquire ultrasonic images of the corresponding two-dimensional cross-section of the object to be scanned in real time during motion scanning, and correcting the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning to obtain the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning further includes: S245: After processing the fused spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process with at least one of the following methods, namely trajectory smoothing, Kalman filter dynamic optimization, and motion physical constraint verification, the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process is obtained.

[0098] By optimizing the trajectory through smoothing, dynamic optimization of Kalman filtering, and verification of motion physical constraints, the accuracy of the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning can be further improved.

[0099] Among them, Kalman filtering dynamic optimization can filter out measurement noise and make the spatial trajectory smoother; by using parameters such as maximum speed and acceleration to perform motion physical constraint verification on the fused spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during motion scanning, the spatial trajectory can be made to conform to objective physical laws.

[0100] like Figure 7 As shown, in one embodiment of this application, S3: the step of obtaining the three-dimensional ultrasound imaging result of the object to be scanned based on the ultrasound image of the corresponding two-dimensional cross-section of the object to be scanned acquired in real time during the motion scanning process of the two-dimensional linear array ultrasound transducer 2, and the spatial trajectory of the two-dimensional linear array ultrasound transducer 2 during the motion scanning process includes: S31: Based on the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process, obtain the three-dimensional spatial transformation matrix of each ultrasonic image.

[0101] Specifically, the three-dimensional spatial range can be dynamically determined based on the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process, the spatial voxel grid can be divided, and the three-dimensional coordinate axis can be generated.

[0102] in, , , To allow for additional space, , , This represents the size of the reconstructed grid.

[0103] Then, based on the motion displacement and attitude information of each frame in the spatial trajectory of the two-dimensional linear array ultrasonic transducer 2 during the motion scanning process, the four-dimensional homogeneous transformation matrix is ​​calculated: .

[0104] S32: Using the three-dimensional spatial transformation matrix of each ultrasound image, all pixels of each ultrasound image are mapped to a voxel grid in three-dimensional space.

[0105] It is understood that the ultrasonic images obtained by the two-dimensional linear array ultrasonic transducer 2 in this application embodiment are two-dimensional images in the x and z directions.

[0106] Therefore, it is necessary to convert the first pixel (pixel coordinate difference vector) of the two-dimensional image into three-dimensional spatial coordinates: in, , This represents the position of a reference pixel in the image coordinate system. , , Represents the actual coordinates of the three axes.

[0107] Then, obtain the standard direction vector after rotation: ,in, , These refer to the reference coordinates in a two-dimensional image frame; the coordinates of all pixels in each frame are calculated in three-dimensional space. And batch map all pixels of each frame to three-dimensional space: in, : The pixel number of the current pixel in the row direction of the image.

[0108] Then, the neighboring voxel index corresponding to the pixel can be calculated: : Round the value down. , , These are the starting indices of the current voxel mesh in the X, Y, and Z directions, respectively, used for coordinate index correction.

[0109] S33: Obtain the average grayscale value of the corresponding pixel points of each voxel in the voxel grid in three-dimensional space to obtain the three-dimensional ultrasound imaging results of the object to be scanned.

[0110] After mapping all two-dimensional images to voxels within a voxel grid in three-dimensional space, the gray-scale mean of each voxel can be calculated to obtain the three-dimensional ultrasound imaging results of the object to be scanned.

[0111] Specifically, a thin, elongated metal needle is pre-inserted inside the pork belly sample as a structural reference. The results obtained using the three-dimensional ultrasonic localization imaging method of this application are as follows: Figure 8 As shown.

[0112] Specifically, Figure 8 A is the XY plane image before reconstruction. Figure 8 B is the XZ plane image before reconstruction. Figure 8 C is the YZ plane image before reconstruction; Figure 8 D is the reconstructed XY plane image. Figure 8 E is the reconstructed XZ plane image. Figure 8 F represents the reconstructed YZ-plane image. The images above illustrate the imaging results of the needle in various directions using maximum intensity projection (MIP). Through comparison... Figure 8 A and Figure 8 D、 Figure 8 B and Figure 8 E, Figure 8 C and Figure 8 F shows that the needle maintains good straightness in all directions, indicating that the image processed by the method of this invention has high spatial accuracy.

[0113] also, Figure 8G represents the final three-dimensional reconstruction result. The reconstructed image accurately reflects the internal structural features of the sample, verifying the spatial consistency and morphological fidelity of the three-dimensional ultrasound localization imaging method in three-dimensional space, and demonstrating its feasibility and effectiveness in practical applications.

[0114] like Figure 1 and Figure 2 As shown, this application also provides a three-dimensional ultrasound imaging scanning device for performing three-dimensional ultrasound imaging on an object to be scanned, and includes a handheld component and a processing control unit; The handheld component includes a two-dimensional linear array ultrasonic transducer 2, an optical flow sensor 4, an inertial measurement unit 1, and at least two ranging sensors 3.

[0115] The two-dimensional linear array ultrasonic transducer 2 is configured to acquire ultrasonic images of the corresponding two-dimensional cross-section of the object to be scanned in real time during motion scanning.

[0116] The inertial measurement unit 1 is equipped with a three-axis gyroscope and a three-axis accelerometer, and is configured to use the three-axis gyroscope and the three-axis accelerometer to acquire in real time the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction during motion scanning.

[0117] The optical flow sensor 4 is configured to acquire images of the outer surface region of the corresponding object to be scanned in real time, and based on the inter-frame pixel grayscale changes of the images of the outer surface region of the corresponding object to be scanned, acquire the relative displacement between the two-dimensional linear array ultrasonic transducer 2 and the outer surface region of the corresponding object to be scanned in real time during the motion scanning process.

[0118] Each ranging sensor 3 is configured to acquire, in real time, the absolute distance between itself and the outer surface region of the corresponding object to be scanned along the corresponding ranging direction.

[0119] The processing control unit is connected to the two-dimensional linear array ultrasonic transducer 2, the optical flow sensor 4, the inertial measurement unit 1 and at least two ranging sensors 3, and is configured to acquire the three-dimensional ultrasonic imaging results of the object to be scanned based on the output signals of the two-dimensional linear array ultrasonic transducer 2, the optical flow sensor 4, the inertial measurement unit 1 and at least two ranging sensors 3.

[0120] The two-dimensional linear array ultrasonic transducer 2, optical flow sensor 4, inertial measurement unit 1 and at least two ranging sensors 3 are all mounted on the housing 5 of the handheld component, allowing the operator to perform ultrasonic scanning by hand. The principle is the same as described above and will not be repeated here.

[0121] The processing and control unit can be an STM32 series microcontroller to control the frame rate of ultrasonic image acquisition of the two-dimensional linear array ultrasonic transducer 2, and to synchronize and transmit multi-sensor data in real time from the optical flow sensor 4, the inertial measurement unit 1 and the ranging sensor 3.

[0122] Specifically, the three-dimensional ultrasound imaging scanning device in this application embodiment can utilize a multi-sensor data acquisition and synchronization control method based on the FreeRTOS real-time operating system. Through multi-task concurrent scheduling, it effectively ensures real-time synchronization and high-frequency reliable acquisition of multi-channel data. The STM32 series microcontroller divides the data into independent tasks that run concurrently, and FreeRTOS implements preemptive task scheduling to ensure that high-priority tasks run first, avoiding data acquisition delays or frame drops.

[0123] Specific implementation steps: Ultrasonic image acquisition task (highest priority): Real-time triggering of the 2D linear array ultrasonic transducer 2 to acquire ultrasonic image data, which will be used as the system's global synchronization clock reference. All sensor data acquisition tasks will respond with the same second priority.

[0124] Optical flow sensor 4 acquisition task: to acquire the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction in real time during the motion scanning process.

[0125] The task of inertial measurement unit 1 is to acquire the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer 2 relative to the reference direction in real time during the motion scanning process.

[0126] Ranging sensor 3 acquisition task: Real-time acquisition of the absolute distance between the sensor and the outer surface area of ​​the corresponding object to be scanned along the corresponding ranging direction. Data packaging and transmission task: responsible for the synchronous organization of data from various sensors, caching and packaging data matrices, and synchronously sending data.

[0127] Each task transmits data through the FreeRTOS message queue, and a unified timestamp mechanism ensures the time consistency of various types of data.

[0128] Compared to existing three-dimensional ultrasound imaging scanning devices based on electromagnetic sensors, the three-dimensional ultrasound imaging scanning device of this application embodiment does not rely on electromagnetic sensors to track the spatial trajectory of the two-dimensional linear ultrasound transducer 2 in real time. Instead, it obtains the spatial trajectory of the two-dimensional linear ultrasound transducer 2 during the motion scanning process by measuring the relative displacement between the two-dimensional linear ultrasound transducer 2 and the corresponding outer surface area of ​​the object to be scanned, and the spatial deflection of the two-dimensional linear ultrasound transducer 2 corresponding to the outer surface area of ​​the object to be scanned. This not only provides high positioning accuracy for the spatial trajectory of the two-dimensional linear ultrasound transducer 2, but also enables positioning through the relative displacement between the three-dimensional ultrasound imaging scanning device and the outer surface area of ​​the object to be scanned. It does not require external magnetic fields or optical monitoring, thus effectively avoiding electromagnetic interference and making it suitable for large-scale free scanning, thereby adapting to various clinical environments.

[0129] The three-dimensional ultrasonic imaging scanning device of this application embodiment combines optical flow sensor 4, inertial measurement unit 1 and ranging sensor 3. Through multi-sensor fusion, it effectively solves the anti-interference problem of existing electromagnetic tracking methods and realizes stable and high-precision three-dimensional ultrasonic scanning imaging in complex environments.

[0130] Specifically, the three-dimensional ultrasound imaging scanning device of this application embodiment is not affected by external interference and can work stably even in clinical environments (such as operating rooms) with complex electromagnetic fields or a large number of metal instruments; and it does not rely on fixed reference points, adapts to relative motion scenarios, and even if there is relative movement between the object to be scanned and the two-dimensional linear array ultrasound transducer 2, it will not affect the accuracy of position tracking and image reconstruction, ensuring scanning continuity and imaging quality.

[0131] The three-dimensional ultrasound imaging scanning device of this application has a compact structure and supports freehand scanning. It can achieve real-time tracking over a large area, along a large path, and in any posture, greatly improving portability and operational flexibility, and overcoming the problems of large size and limited scanning of existing three-dimensional ultrasound imaging scanning devices.

[0132] Furthermore, the three-dimensional ultrasound imaging scanning device of this application embodiment can actively detect the motion trajectory dead zone problem of the optical flow sensor 4 when the outer surface texture of the object to be scanned is uniform, as well as the drift error caused by the accumulation of relative displacement. It can also automatically correct the trajectory in real time through the image fusion algorithm, which significantly improves the measurement accuracy of the motion trajectory and the stability of system operation, ensures the spatial consistency of ultrasound image stitching and the overall accuracy of three-dimensional reconstruction, realizes real-time compensation of motion error at the algorithm level, greatly improves the three-dimensional imaging quality and system robustness, and ensures the imaging stability and reconstruction reliability in complex clinical environments.

[0133] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications or equivalent substitutions made within the spirit and principles of this application should be included within the protection scope of this application.

[0134] Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein. The scope of this application is defined by the appended claims.

Claims

1. A method of three-dimensional ultrasonic localization imaging, characterized by, The application is applied to three-dimensional ultrasonic imaging of a scanning object, and comprises: acquiring an ultrasonic image of a corresponding two-dimensional section of the scanning object in real time by using a two-dimensional linear array ultrasonic transducer (2) in a motion scanning process; acquiring a spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process, wherein the spatial trajectory comprises spatial displacement and spatial attitude change; acquiring a three-dimensional ultrasonic imaging result of the scanning object based on the ultrasonic image of the corresponding two-dimensional section of the scanning object acquired in real time by the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process and the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process; wherein the step of acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process comprises: acquiring a relative displacement between the two-dimensional linear array ultrasonic transducer (2) and a surface region of the scanning object in real time in the motion scanning process; acquiring a spatial deflection of the surface region of the scanning object in real time by the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process; acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process based on the relative displacement between the two-dimensional linear array ultrasonic transducer (2) and the surface region of the scanning object in the motion scanning process and the spatial deflection of the surface region of the scanning object by the two-dimensional linear array ultrasonic transducer (2).

2. The method of three-dimensional ultrasonic localization imaging of claim 1, wherein, The step of acquiring the spatial deflection of the surface region of the scanning object in real time by the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process comprises: acquiring an absolute spatial attitude of the two-dimensional linear array ultrasonic transducer (2) relative to a reference direction in real time in the motion scanning process; acquiring a relative spatial deflection of the surface region of the scanning object by the two-dimensional linear array ultrasonic transducer (2) in real time in the motion scanning process; acquiring the spatial deflection of the surface region of the scanning object in real time based on the absolute spatial attitude of the two-dimensional linear array ultrasonic transducer (2) relative to the reference direction in the motion scanning process and the relative spatial deflection of the surface region of the scanning object by the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process.

3. The method of three-dimensional ultrasonic localization imaging of claim 2, wherein, The step of acquiring the relative spatial deflection of the surface region of the scanning object by the two-dimensional linear array ultrasonic transducer (2) in real time in the motion scanning process comprises: acquiring an absolute distance between each distance measuring sensor (3) and the surface region of the scanning object along a corresponding distance measuring direction in real time by using at least two distance measuring sensors (3), wherein each distance measuring sensor (3) is fixed relative to the two-dimensional linear array ultrasonic transducer (2); acquiring the relative spatial deflection of the surface region of the scanning object by the two-dimensional linear array ultrasonic transducer (2) in real time in the motion scanning process based on the absolute distance between each distance measuring sensor (3) and the surface region of the scanning object along a corresponding distance measuring direction acquired in real time.

4. The method of claim 2, wherein, The step of acquiring the absolute spatial pose of the two-dimensional linear array ultrasonic transducer (2) relative to the reference direction in the motion scanning process in real time comprises: The absolute spatial pose of the two-dimensional linear array ultrasonic transducer (2) relative to the reference direction in the motion scanning process is acquired in real time by using an inertial measurement unit (1) provided with a three-axis gyroscope and a three-axis accelerometer, wherein the inertial measurement unit (1) is fixed relative to the two-dimensional linear array ultrasonic transducer (2).

5. The method of claim 1, wherein, The step of acquiring the relative displacement between the two-dimensional linear array ultrasonic transducer (2) and the outer surface region of the object to be scanned in the motion scanning process in real time comprises: The relative displacement between the two-dimensional linear array ultrasonic transducer (2) and the outer surface region of the object to be scanned in the motion scanning process is acquired in real time by using an optical flow sensor (4) to acquire images of the outer surface region of the object to be scanned, and based on the interframe pixel gray scale changes of the images of the outer surface region of the object to be scanned, wherein the optical flow sensor (4) is fixed relative to the two-dimensional linear array ultrasonic transducer (2).

6. The three-dimensional ultrasonic localization imaging method according to any one of claims 1 to 5, characterized in that, The step of acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process further comprises: The spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process is corrected to acquire a corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process by acquiring ultrasonic images of the corresponding two-dimensional cross sections of the object to be scanned in the motion scanning process by using the two-dimensional linear array ultrasonic transducer (2).

7. The method of three-dimensional ultrasonic localization imaging of claim 6, wherein, The step of acquiring the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process further comprises: Acquiring a to-be-corrected spatial trajectory segment in the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process; Acquiring feature points in the ultrasonic images corresponding to the to-be-corrected spatial trajectory segment and feature identifiers of the feature points; Acquiring image estimation trajectory change amounts between the ultrasonic images by using the ultrasonic images with the feature points and the feature identifiers of the feature points; Acquiring fusion estimation trajectory change amounts between the ultrasonic images by using the spatial estimation trajectory change amounts between the ultrasonic images acquired in the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process and the image estimation trajectory change amounts between the ultrasonic images, and further acquiring a fused spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process.

8. The method of three-dimensional ultrasonic localization imaging of claim 7, wherein, The two-dimensional linear array ultrasonic transducer (2) is used to obtain the ultrasonic image of the corresponding two-dimensional section of the object to be scanned in the motion scanning process in real time, the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process is corrected, and the step of obtaining the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process further comprises: After at least one of trajectory smoothing, Kalman filter dynamic optimization, and motion physical constraint test is performed on the fused spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process, the corrected spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process is obtained.

9. The method of claim 6, wherein, Based on the ultrasonic image of the corresponding two-dimensional section of the object to be scanned obtained by the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process in real time and the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process, the step of obtaining the three-dimensional ultrasonic imaging result of the object to be scanned comprises: Based on the spatial trajectory of the two-dimensional linear array ultrasonic transducer (2) in the motion scanning process, a three-dimensional spatial transformation matrix of each ultrasonic image is obtained; Using the three-dimensional spatial transformation matrix of each ultrasonic image, all pixel points of each ultrasonic image are mapped into a voxel grid in three-dimensional space; The gray mean value of each voxel in the voxel grid in three-dimensional space corresponding to the pixel points is obtained to obtain the three-dimensional ultrasonic imaging result of the object to be scanned.

10. A three-dimensional ultrasonic imaging scanning device, characterized by It is applied to three-dimensional ultrasonic imaging of an object to be scanned and comprises a handheld assembly and a processing control unit. The handheld assembly comprises a two-dimensional linear array ultrasonic transducer (2), an optical flow sensor (4), an inertial measurement unit (1), and at least two distance sensors (3). The two-dimensional linear array ultrasonic transducer (2) is configured to obtain the ultrasonic image of the corresponding two-dimensional section of the object to be scanned in real time in the motion scanning process. The inertial measurement unit (1) is provided with a three-axis gyroscope and a three-axis accelerometer, and is configured to obtain the absolute spatial posture of the two-dimensional linear array ultrasonic transducer (2) relative to a reference direction in the motion scanning process in real time by using the three-axis gyroscope and the three-axis accelerometer. The optical flow sensor (4) is configured to obtain an image of the outer surface region of the object to be scanned in real time, and to obtain the relative displacement between the two-dimensional linear array ultrasonic transducer (2) and the outer surface region of the object to be scanned in the motion scanning process in real time based on the interframe pixel gray change of the image of the outer surface region of the object to be scanned. Each distance sensor (3) is configured to obtain the absolute distance between the corresponding distance sensor and the outer surface region of the object to be scanned in real time. The processing control unit is in signal connection with the two-dimensional linear array ultrasonic transducer (2), the optical flow sensor (4), the inertial measurement unit (1) and the at least two ranging sensors (3), and is configured to obtain a three-dimensional ultrasonic imaging result of the object to be scanned based on output signals of the two-dimensional linear array ultrasonic transducer (2), the optical flow sensor (4), the inertial measurement unit (1) and the at least two ranging sensors (3).

Images