A tube current modulation method, device and medium

Abstract

This application provides a tube current modulation method, apparatus, and medium, applicable to the field of imaging equipment technology. The method uses a target image and the segmentation results of the target object within that image. Based on the target image and the segmentation results, it determines the scanning range and scanning center point of a scanning device. Based on the scanning range and center point, it obtains a tube current modulation curve, and then adjusts the scanning current of the scanning device based on this curve. This enables dynamic adjustment of scanning parameters during image guidance, improving the image quality obtained by the scanning device. Furthermore, the target image and the segmentation results of the target object used in this application accurately reflect the cross-sectional structure of the target object. Compared to using a two-dimensional positioning image, it can effectively distinguish the thickness differences of overlapping objects, thereby generating a more accurate tube current modulation curve.

Description

Technical Field

[0001] This application relates to the field of imaging equipment technology, and in particular to a tube current modulation method, device and medium. Background Technology

[0002] With the rapid development of computer and imaging equipment technology, image guidance technology has become increasingly important. Image guidance refers to the technology of accurately locating and guiding scanning equipment to scan a target object based on real-time or near-real-time images. However, current image guidance mostly uses cone-beam computed tomography (CBCT), whose scanning parameters, such as scanning voltage and scanning current (also known as tube current), are usually fixed or manually preset. This is not conducive to reducing the scanning radiation dose of the scanning equipment and can lead to poor image quality, such as overexposure or underexposure in certain areas of the image, resulting in poor image positioning accuracy and thus affecting the image guidance effect. How to dynamically adjust scanning parameters in image guidance to improve the image quality obtained by the scanning equipment, thereby improving positioning accuracy and image guidance effect, and reducing radiation dose, has become a technical problem to be solved. Summary of the Invention

[0003] This application provides a tube current modulation method, device, and medium that can dynamically adjust scanning parameters during image guidance, thereby improving the image quality obtained by the scanning device, improving positioning accuracy and image guidance effect, and reducing radiation dose.

[0004] In a first aspect, embodiments of this application provide a tube current modulation method, the method comprising:

[0005] Acquire a target image and obtain the segmentation result of the target object in the target image, wherein the target image is a three-dimensional image and includes the target object;

[0006] Based on the segmentation results of the target image and the target object, the scanning range and scanning center point of the scanning device are determined, and the scanning device instructs the device to scan the entity object corresponding to the target object to acquire the target image;

[0007] Based on the scanning range and the scanning center point, a tube current modulation curve is obtained; the tube current modulation curve is used to adjust the tube current of the scanning device.

[0008] Optionally, obtaining the tube current modulation curve based on the scanning range and the scanning center point includes:

[0009] Determine the equivalent value of each position in the scanning range; wherein, the equivalent value of the first position indicates the equivalent thickness value of the scanning ray emitted by the scanning device from the first position to the scanning center point, the equivalent value of the first position is related to the voxel information of the first position in the target image, and the first position is any one of the positions;

[0010] The tube current modulation curve is obtained based on the equivalent values ​​at each of the aforementioned locations.

[0011] Optionally, determining the equivalent value of the first position includes:

[0012] Based on the voxel information between the first position and the scanning center point, and the target correspondence, the equivalent value of the first position is determined;

[0013] The target correspondence indicates the correspondence between the equivalent value of the first position and the voxel information.

[0014] Optionally, if the voxel information includes N voxels on the scanning ray penetration path, where N is a positive integer, the length of each voxel in the scanning ray penetration path, and the linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the degree of attenuation when the scanning ray passes through the structure corresponding to that voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0015] The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes:

[0016] Based on the voxel information and formula (1), the equivalent value of the first position is determined:

[0017]

[0018] Where WET(x, y, z) is the equivalent value at the first position, N is the number of voxels along the scanning ray's penetration path, and μ i μ is the linear decay coefficient of the i-th voxel; 水 Δd is the attenuation coefficient of water under a preset voltage. i Let be the length of the i-th voxel along the path of the scanning ray.

[0019] Optionally, if the voxel information includes N voxels on the scanning ray penetration path, the voxel value of each voxel in the N voxels, and the length of each voxel on the scanning ray penetration path, the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0020] The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes:

[0021] Based on the voxel information and formula (2), the equivalent value of the first position is determined:

[0022]

[0023] Where WET(x, y, z) is the equivalent value at the first position, N is the number of voxels along the path of the scanning ray, HUi is the voxel value of the i-th voxel, and Δd i Let be the length of the i-th voxel along the path of the scanning ray.

[0024] Optionally, obtaining the tube current modulation curve based on the equivalent values ​​at each of the locations includes:

[0025] Based on the equivalent values ​​at each location, the tube current value at each location is determined.

[0026] Specifically, the tube current value at the first position is determined based on the equivalent value at the first position, and the tube current value at the first position is positively correlated with the equivalent value at the first position.

[0027] Based on the tube current values ​​at each location, the tube current modulation curve is obtained.

[0028] Optionally, determining the tube current value at the first position based on the equivalent value at the first position includes:

[0029] Based on the equivalent value at the first position and formula (3), the tube current value at the first position is determined:

[0030]

[0031] Where mA(x, y, z) is the tube current value at the first position, WET(x, y, z) is the equivalent value at the first position, and mA base The mA value is based on a preset baseline value in the scanning protocol. base A number greater than 0 and less than 1; WET base f is a preset reference equivalent value based on the scanning protocol, k is a preset modulation index, and k is greater than 0. 组织 As a correction factor, and f 组织 Greater than 0.

[0032] Optionally, the equivalent value of the first position is a value in the first coordinate system, and determining the tube current value at the first position based on the equivalent value of the first position includes:

[0033] Based on the equivalent value of the first position, the initial tube current value of the first position is determined; the initial tube current value of the first position indicates the tube current value of the first position in the first coordinate system.

[0034] Based on the transformation relationship between the first coordinate system and the second coordinate system, the tube current value at the first position is determined; the tube current value at the first position is the tube current value in the second coordinate system.

[0035] Wherein, the first coordinate system is the DICOM coordinate system for medical digital imaging and communication, and the origin of the first coordinate system is the scanning center point; the second coordinate system is the IEC coordinate system.

[0036] Secondly, embodiments of this application provide a tube current modulation device, the device comprising:

[0037] The first acquisition unit is used to acquire a target image and acquire a segmentation result of a target object in the target image, wherein the target image is a three-dimensional image and the target image includes the target object;

[0038] The determining unit is used to determine the scanning range and scanning center point of the scanning device based on the segmentation result of the target image and the target object, wherein the scanning device is an instruction to scan the entity object corresponding to the target object and to acquire the target image;

[0039] The second acquisition unit is used to acquire a tube current modulation curve based on the scanning range and the scanning center point; the tube current modulation curve is used to adjust the tube current of the scanning device.

[0040] Thirdly, embodiments of this application provide a computer program product, the computer program product comprising: a computer program (also referred to as code or instructions), which, when the computer program is run, causes the computer to perform the method in any of the possible implementations of any of the above aspects.

[0041] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program (also referred to as code or instructions) that, when run on a computer, causes the computer to perform the method in any of the possible implementations of any of the above aspects.

[0042] Fifthly, embodiments of this application provide a chip system including one or more processors for calling and executing instructions stored in memory, causing the methods in any of the above aspects or possible implementations to be executed. The chip system may be composed of chips or may include chips and other discrete devices.

[0043] This application provides a tube current modulation method, apparatus, and medium. The method uses a target image and the segmentation results of the target object within that image. Based on the target image and the segmentation results, it determines the scanning range and center point of a scanning device. Based on the scanning range and center point, it obtains a tube current modulation curve, and then adjusts the scanning current of the scanning device based on this curve. Therefore, this application can utilize tube current modulation to dynamically adjust the tube current of the scanning device according to the thickness, density, and attenuation characteristics of the target object, thereby achieving dynamic adjustment of scanning parameters during image guidance and improving the image quality obtained by the scanning device. Furthermore, the target image used in this application is a three-dimensional image including the target object. Using the target image and the segmentation results of the target object within it accurately reflects the cross-sectional structure of the target object. Compared to using a two-dimensional positioning image, it can effectively distinguish the thickness differences of overlapping objects, thus generating a more accurate tube current modulation curve, thereby improving positioning accuracy and image guidance effect, and further reducing the radiation dose of the scanning device. Attached Figure Description

[0044] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0045] Figure 1 A flowchart of a tube current modulation method provided in this application embodiment;

[0046] Figure 2 A schematic diagram of a set of localization CT images and target object segmentation results provided for embodiments of this application;

[0047] Figure 3 A schematic diagram provided for embodiments of this application includes the scanning range and scanning center point corresponding to a CT device scanning a solid object;

[0048] Figure 4 A schematic diagram of a scanning device at a first position emitting scanning rays through a target object, provided in an embodiment of this application;

[0049] Figure 5 This is a schematic diagram of a tube current modulation device provided in an embodiment of this application. Detailed Implementation

[0050] To enable those skilled in the art to better understand the present application, the technical solutions in this embodiment 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 in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0051] First, let's introduce the technical terms used in the embodiments of this application.

[0052] Tube Current Modulation (TCM) is a technique that dynamically adjusts the tube current of the scanning radiation during scanning based on the thickness, density, and attenuation characteristics of the object being scanned. For example, TCM can dynamically adjust the tube current of the scanning radiation during computed tomography (CT) scans. By using real-time or pre-calculated attenuation coefficients, this technique can automatically adjust the tube current of each scan layer or scan line, thereby improving the image quality obtained by the scanning equipment. For CT equipment, it can also reduce the amount of radiation agent used.

[0053] The working principle of TCM technology is as follows: When the scanning device scans, the scanning rays generate a specific current (referred to as tube current). These scanning rays pass through the target object and are received by the detector, thereby acquiring a scanned image. Before or during scanning, the scanning device calculates the attenuation of the scanning ray's penetration path in real time and adjusts the tube current accordingly to meet the attenuation requirements of different types of target objects.

[0054] However, the tube current of the current scanning X-ray is fixed or manually set according to preset conditions. In other words, the tube current of the current scanning X-ray cannot be dynamically adjusted according to the needs of the target object. For example, when scanning a target object with a high thickness, if the tube current is too low, penetration cannot be guaranteed, which results in poor image quality, such as overexposure or underexposure in some areas of the image, leading to poor image positioning accuracy and thus affecting the image guidance effect.

[0055] In view of this, embodiments of this application provide a tube current modulation method. This method uses a target image and the segmentation results of the target object within the target image. Based on the target image and the segmentation results of the target object, it determines the scanning range and scanning center point of the scanning device. Based on the scanning range and scanning center point of the scanning device, it obtains a tube current modulation curve, and adjusts the scanning current of the scanning device based on the tube current modulation curve. Therefore, embodiments of this application can utilize tube current modulation to dynamically adjust the tube current of the scanning device according to the thickness, density, and attenuation characteristics of the target object, thereby achieving dynamic adjustment of scanning parameters during image guidance and improving the image quality obtained by the scanning device. Furthermore, the target image used in embodiments of this application is a three-dimensional image that includes the target object. Using the target image and the segmentation results of the target object within the target image can accurately reflect the cross-sectional structure of the target object. Compared to using a two-dimensional positioning image, it can effectively distinguish the thickness differences of overlapping tissues, thereby generating a more accurate tube current modulation curve, thus improving positioning accuracy and image guidance effect.

[0056] The following description, in conjunction with the accompanying drawings, provides a detailed and complete discussion of the tube current modulation method and its application scenarios provided in the embodiments of this application.

[0057] First, we introduce the application scenarios of the tube current modulation method provided in the embodiments of this application.

[0058] For example, the tube current modulation method can be applied to a computing device that can acquire a target image and the segmentation result of the target object in the target image, and the computing device can process the target image and the segmentation result of the target object to generate a tube current modulation curve.

[0059] Furthermore, the computing device provided in this application embodiment is also used to connect to the scanning device, and the computing device can dynamically adjust the tube current of the scanning device according to the tube current modulation curve.

[0060] The computing device provided in this application embodiment can be a desktop computer, server, cloud server, mobile terminal or other device with computing function, and this application embodiment is not specifically limited.

[0061] The following describes a tube current modulation method provided by an embodiment of this application.

[0062] Appendix Figure 1 A flowchart of a tube current modulation method provided in this application embodiment is shown. The method includes the following steps S110 to S130:

[0063] S110. Obtain a target image and obtain the segmentation result of the target object in the target image, wherein the target image is a three-dimensional image and includes the target object.

[0064] The correspondence between a target object and an entity object refers to the display information of the entity object in the target image. In the embodiments of this application, an entity object refers to an object that needs to be scanned by a scanning device. For example, an entity object can be a cultural relic, luggage, or a patient's organ, etc., and the embodiments of this application are not specifically limited.

[0065] A target image refers to a three-dimensional image obtained by scanning a physical object using a scanning device. In the embodiments of this application, the target image includes the target object. For example, in the field of CT, the target image can be a series of three-dimensional CT scan images with a resolution greater than a preset resolution threshold obtained by scanning a physical object using a CT device. It can be understood that, compared with a two-dimensional positioning image, the target image can effectively distinguish the thickness differences of overlapping target objects.

[0066] The segmentation result of a target object in a target image refers to the result obtained after separating the target object from the target image and accurately depicting its contour. The segmentation result of a target object includes its contour information, such as its contour coordinates.

[0067] In one example, the computing device can first acquire a target image, and then use image analysis techniques to separate the target object from the target image, thereby obtaining the segmentation result of the target object.

[0068] In another example, if the target image is a three-dimensional image corresponding to the localization CT image obtained after scanning by a CT device, and is applied before radiotherapy, the computing device can obtain the contour information of the target object from the RadiationTherapy Structure Set (RTStruct) file corresponding to the target image.

[0069] It is understandable that since the CT images obtained after scanning by the CT equipment are two-dimensional images, the computing device can reconstruct the localized CT images to obtain three-dimensional target images and the outline display results of the target objects in the target images. It can be understood that the outline display results are three-dimensional irregular body data.

[0070] Exemplary illustration, attached Figure 2 This is a schematic diagram illustrating a set of localization CT images and the segmentation results of the target object provided in an embodiment of this application. For example... Figure 2 As shown, the localization CT images and target object segmentation results are presented from three perspectives. Among them, Figure 2 (a) shows the localization CT image at the first angle and the outline display result of the target object in the localization CT image at the first angle. Figure 2 (b) shows the positioning CT image from the second angle and the outline display result of the target object in the positioning CT image from the second angle. Figure 2 (c) shows the third-angle localization CT image and the outline display result of the target object in the third-angle localization CT image.

[0071] like Figure 2 As shown, the computing device can reconstruct a three-dimensional localization CT image by combining the localization CT images from these three angles with the segmentation results of the target object.

[0072] In this embodiment of the application, the computing device first acquires the target image and the segmentation result of the target object, and then processes the segmentation result of the target image and the target object to acquire the tube current modulation curve.

[0073] S120. Based on the segmentation results of the target image and the target object, determine the scanning range and scanning center point of the scanning device, and instruct the device to scan the entity object corresponding to the target object to obtain the target image.

[0074] The scanning range refers to the three-dimensional area covered by the scanning device when scanning a physical object. The scanning range is defined by the start point and end point of the scan. In the embodiments of this application, the boundaries of the scanning range clearly indicate the maximum and minimum coordinate positions that the scanning device can scan.

[0075] The scan center point is a point on the central axis of the target object, which is crucial for ensuring the accuracy and uniformity of the CT scan. In this embodiment, the scan center point can be the area focused during the scan.

[0076] Exemplary illustration, attached Figure 3 This is a schematic diagram illustrating the scanning range and center point corresponding to a CT scanner scanning a physical object, as provided in an embodiment of this application. Figure 3 As shown, the scanning center point is located at the center of the chest of the object, and the scanning range covers the entire chest. The starting point of the scanning range is point A, the ending point is point B, and the direction from point A to point B is the scanning direction.

[0077] In this embodiment of the application, the computing device can obtain the scanning range and scanning center point of the scanning device based on the segmentation results of the target image and the target object.

[0078] For example, the computing device can analyze the localization CT image to identify the location of the target object. Then, based on the segmentation results of the target object in the localization CT image, the computing device can digitally identify the contour coordinates of the target object. Next, based on the location of the target object and the segmentation results, the computing device can obtain a three-dimensional bounding box including the target object and its surrounding key structures; this three-dimensional bounding box is the scan range. The center point of the target object region is determined as the scan center point.

[0079] It is understood that, in the embodiments of this application, the computing device can accurately determine the scanning range and scanning center point of the scanning device based on the segmentation results of the target image and the target object, thereby avoiding additional positioning image scanning and reducing the radiation dose received by the scanned object.

[0080] S130. Based on the scanning range and the scanning center point, obtain the tube current modulation curve; the tube current modulation curve is used to adjust the tube current of the scanning device.

[0081] In this embodiment, the computing device determines the equivalent value of each position within the scanning range based on the scanning range and scanning center point of the scanning device, and determines the tube current value at each position based on the equivalent value of each position. To better illustrate the equivalent value at each position, the following description uses only the first position as an example, where the first position is any position within the scanning range.

[0082] The equivalent value at the first position indicates the equivalent thickness of the scanning rays emitted by the scanning device from the first position to the scanning center point. The equivalent value at the first position is related to the voxel information at the first position in the target image.

[0083] The voxel information at the first position describes the voxel situation at the first position, including, but not limited to, N voxels along the scanning ray penetration path from the first position to the scanning center point, the length of each voxel in the scanning ray penetration path, and the linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the degree of attenuation when the scanning ray passes through the structure corresponding to that voxel. Here, N is a positive integer. Furthermore, the voxel information at the first position may also include the voxel coordinates of each voxel, the CT value (in HU) contained in the voxel, etc., which are not specifically limited in this embodiment.

[0084] Since voxel information can directly reflect the density and geometric features of the target object at that location, the equivalent value of the first location can be accurately determined by using the voxel information of the first location, compared to relying solely on the frontal or lateral two-dimensional projection image.

[0085] Specifically, the computing device can determine the equivalent value of the first position based on the voxel information of the first position and the target correspondence. The target correspondence indicates the correspondence between the equivalent value of the first position and the voxel information of the first position. Through this correspondence, the computing device can automatically and accurately determine the equivalent value of the first position.

[0086] In one example, the target correspondence can be shown as in formula (1):

[0087]

[0088] Where WET(x, y, z) is the equivalent value at the first position, N is the number of voxels along the scanning ray's penetration path, and μ i μ is the linear decay coefficient of the i-th voxel; 水 The attenuation coefficient of water at a preset voltage (e.g., when the preset voltage is 120KV, μ) 水 (0.19 / cm); Δd i The length of the i-th voxel along the penetration path of the scanning ray is calculated using a geometric projection model.

[0089] Exemplary illustration, such as Figure 4 The diagram shown is a structural schematic of a scanning device at a first position, according to an embodiment of this application, which emits scanning rays that pass through a target object. Figure 4 As shown, the scanning device is a CT scanner (also known as a CT tube), and the location of the scanning device is the first position (x, y, z). The scanning ray is emitted from the first position and passes through the scanning center point, which is the scanning ray projection path 401. The embodiments of this application can determine the equivalent value of the current position (i.e., the first position) based on formula (1).

[0090] In another example, because the HU value satisfies Therefore, formula (1) can be transformed to obtain formula (2):

[0091]

[0092] Where HUi is the voxel value of the i-th voxel, and Δd i Let be the length of the i-th voxel along the scanning ray penetration path.

[0093] In this embodiment of the application, the computing device can obtain the equivalent value of the first position based on formula (2). For example, see below. Figure 4 As shown, using scanning rays and Figure 4The two intersection points of the contour information of the target object are intersection point A1 and intersection point A2, which form the scanning ray penetration path. Based on the CT value of the voxel in the scanning ray penetration path, the equivalent value of the first position can be calculated. The embodiment of this application adopts formula (2), which has less computational load than formula (1) and can significantly improve the calculation speed and accuracy.

[0094] It should be noted that the equivalent value of the first position can also be obtained in other ways in the embodiments of this application, and the embodiments of this application are not specifically limited.

[0095] Furthermore, after obtaining the equivalent values ​​at each position within the scanning range, the tube current value at each position can be determined based on these equivalent values. For ease of explanation, the first position is still taken as an example. Specifically, the tube current value at the first position is determined based on the equivalent value at the first position. The tube current value at the first position is positively correlated with the equivalent value at the first position.

[0096] For example, if the equivalent value of the first position is high, meaning the first position is a high equivalent value region, such as the pelvic bone region, the tube current value at the first position is high. This means that during scanning, the scanning device can penetrate the target object with a high tube current. Conversely, if the equivalent value of the first position is low, meaning the first position is a low equivalent value region, such as the lung field region, the tube current value at the first position is low. This means that during scanning, the scanning device can penetrate the target object with a low tube current. The technology in this embodiment can dynamically adjust the tube current according to the thickness of the target object, effectively improving image quality and reducing radiation dose.

[0097] Furthermore, the computing device can determine the tube current value at the first position based on the tube current value at the first position and formula (3):

[0098]

[0099] Where mA(x, y, z) is the tube current value at the first position, WET(x, y, z) is the equivalent value at the first position, and mA base The mA value is based on a preset baseline value in the scanning protocol. base A number greater than 0 and less than 1; WET base f is a preset reference equivalent value based on the scanning protocol, k is a preset modulation index, and k is greater than 0. 组织 As a correction factor, and f 组织 Greater than 0.

[0100] Furthermore, in the embodiments of this application, mA baseThe k-value can be determined based on the scanning protocol and the shape of the scanned object. The k-value can be obtained by combining the outer contour of the target object's segmentation results with the object's thickness, and automatically assigned a value based on the object's thickness. 组织 Used to compensate for specific factors, and its value depends on the type of specific factor. For example, if the specific factor is a skeletal region, f can take a value between 1.1 and 1.2 to compensate for the additional attenuation caused by high-density bone tissue. Sensitive organs: for example, the breast, f... 组织 =0.7, for example, the eye, f 组织 =0.5 to limit the dosage. Further, f 组织 The system automatically determines the tissue area being scanned by analyzing the intersection of the scanning rays with the outline of the target object and assigns values ​​accordingly.

[0101] It should be noted that the embodiments of this application can be determined through actual testing and verification of the software and hardware conditions of the scanning device, and the embodiments of this application are not specifically limited.

[0102] Furthermore, in the embodiments of this application, the tube current values ​​obtained at each location are in the Digital Imaging and Communications in Medicine (DICOM) coordinate system, in which the origin is the scanning center point.

[0103] The computing device can convert the tube current value in the first coordinate system to the tube current value in the second coordinate system. The second coordinate system is the International Electrotechnical Commission (IEC) coordinate system.

[0104] It is understood that the first coordinate system and the second coordinate system have a fixed transformation relationship. The computing device can convert the tube current value in the first coordinate system to the tube current value in the second coordinate system based on this transformation relationship. The tube current in the tube current modulation curve is the tube current in the second coordinate system.

[0105] S140. Perform tube current modulation using the tube current modulation curve.

[0106] In this embodiment, the computing device can guide the scanning device to perform current modulation based on the tube current modulation curve.

[0107] For example, the computing device can obtain the tube current value of the CT device at different rotation angles in each revolution during scanning based on the tube current modulation curves at various positions. Combined with the response accuracy of the CT device's tube current control, current modulation is performed in the target direction of the physical object. The target direction can be the Z-axis direction of the second coordinate system or the XY plane of the second coordinate system; this embodiment is not specifically limited.

[0108] The tube current modulation method provided in this application involves obtaining a target image and the segmentation results of the target object within that image. Based on the target image and the segmentation results, the scanning range and center point of the scanning device are determined. A tube current modulation curve is then obtained based on the scanning range and center point, and the scanning current of the scanning device is adjusted accordingly. Therefore, this application can utilize tube current modulation to dynamically adjust the tube current of the scanning device based on the thickness, density, and attenuation characteristics of the target object. This allows for dynamic adjustment of scanning parameters during image guidance, thereby improving the image quality obtained by the scanning device. Furthermore, the target image used in this application is a three-dimensional image that includes the target object. Using the target image and the segmentation results of the target object within it accurately reflects the cross-sectional structure of the target object. Compared to using a two-dimensional positioning image, it can effectively distinguish the thickness differences of overlapping objects, thus generating a more accurate tube current modulation curve, thereby improving positioning accuracy and image guidance effect.

[0109] In addition, this application also provides a tube current modulation device.

[0110] Appendix Figure 5 This is a schematic diagram of a tube current modulation device provided in an embodiment of this application. The device 500 includes:

[0111] The first acquisition unit 501 is used to acquire a target image and acquire the segmentation result of a target object in the target image, wherein the target image is a three-dimensional image and the target image includes the target object;

[0112] The determining unit 502 is used to determine the scanning range and scanning center point of the scanning device based on the segmentation result of the target image and the target object, wherein the scanning device is an instruction to scan the entity object corresponding to the target object and to acquire the target image.

[0113] The second acquisition unit 503 is used to acquire a tube current modulation curve based on the scanning range and the scanning center point; the tube current modulation curve is used to adjust the tube current of the scanning device.

[0114] Optionally, the determining unit 502 is specifically used for, including:

[0115] Determine the equivalent value of each position in the scanning range; wherein, the equivalent value of the first position indicates the equivalent thickness value of the scanning ray emitted by the scanning device from the first position to the scanning center point, the equivalent value of the first position is related to the voxel information of the first position in the target image, and the first position is any one of the positions;

[0116] The tube current modulation curve is obtained based on the equivalent values ​​at each of the aforementioned locations.

[0117] Optionally, determining the equivalent value of the first position includes:

[0118] Based on the voxel information between the first position and the scanning center point, and the target correspondence, the equivalent value of the first position is determined;

[0119] The target correspondence indicates the correspondence between the equivalent value of the first position and the voxel information.

[0120] Optionally, if the voxel information includes N voxels on the scanning ray penetration path, where N is a positive integer, the length of each voxel in the scanning ray penetration path, and the linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the degree of attenuation when the scanning ray passes through the structure corresponding to that voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0121] The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes:

[0122] Based on the voxel information and formula (1), the equivalent value of the first position is determined:

[0123]

[0124] Where WET(x, y, z) is the equivalent value at the first position, N is the number of voxels along the scanning ray's penetration path, and μ i μ is the linear decay coefficient of the i-th voxel; 水 Δd is the attenuation coefficient of water under a preset voltage. i Let be the length of the i-th voxel along the path of the scanning ray.

[0125] Optionally, if the voxel information includes N voxels on the scanning ray penetration path, the voxel value of each voxel in the N voxels, and the length of each voxel on the scanning ray penetration path, the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0126] The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes:

[0127] Based on the voxel information and formula (2), the equivalent value of the first position is determined:

[0128]

[0129] Where WET(x, y, z) is the equivalent value at the first position, N is the number of voxels along the path of the scanning ray, HUi is the voxel value of the i-th voxel, and Δd i Let be the length of the i-th voxel along the path of the scanning ray.

[0130] Optionally, obtaining the tube current modulation curve based on the equivalent values ​​at each of the locations includes:

[0131] Based on the equivalent values ​​at each location, the tube current value at each location is determined.

[0132] Specifically, the tube current value at the first position is determined based on the equivalent value at the first position, and the tube current value at the first position is positively correlated with the equivalent value at the first position.

[0133] Based on the tube current values ​​at each location, the tube current modulation curve is obtained.

[0134] Optionally, determining the tube current value at the first position based on the equivalent value at the first position includes:

[0135] Based on the equivalent value at the first position and formula (3), the tube current value at the first position is determined:

[0136]

[0137] Where mA(x, y, z) is the tube current value at the first position, WET(x, y, z) is the equivalent value at the first position, and mA base The mA value is based on a preset baseline value in the scanning protocol. base A number greater than 0 and less than 1; WET base f is a preset reference equivalent value based on the scanning protocol, k is a preset modulation index, and k is greater than 0. 组织 As a correction factor, and f 组织 Greater than 0.

[0138] Optionally, the equivalent value of the first position is a value in the first coordinate system, and determining the tube current value at the first position based on the equivalent value of the first position includes:

[0139] Based on the equivalent value of the first position, the initial tube current value of the first position is determined; the initial tube current value of the first position indicates the tube current value of the first position in the first coordinate system.

[0140] Based on the transformation relationship between the first coordinate system and the second coordinate system, the tube current value at the first position is determined; the tube current value at the first position is the tube current value in the second coordinate system.

[0141] Wherein, the first coordinate system is the DICOM coordinate system for medical digital imaging and communication, and the origin of the first coordinate system is the scanning center point; the second coordinate system is the IEC coordinate system.

[0142] The tube current modulation device provided in this application embodiment uses a target image and the segmentation results of the target object in the target image. Based on the target image and the segmentation results of the target object, it determines the scanning range and scanning center point of the scanning device. Based on the scanning range and scanning center point of the scanning device, it obtains a tube current modulation curve, and adjusts the scanning current of the scanning device based on the tube current modulation curve. Therefore, this application embodiment can utilize tube current modulation to dynamically adjust the tube current of the scanning device according to the thickness, density, and attenuation characteristics of the target object, thereby achieving dynamic adjustment of scanning parameters in image guidance and improving the image quality obtained by the scanning device. Furthermore, the target image used in this application embodiment is a three-dimensional image that includes the target object. Using the target image and the segmentation results of the target object in the target image can accurately reflect the cross-sectional structure of the target object. Compared with using a two-dimensional positioning image, it can effectively distinguish the thickness differences of overlapping objects, thereby generating a more accurate tube current modulation curve, thus improving positioning accuracy and image guidance effect.

[0143] According to the method provided in the embodiments of this application, this application also provides a chip system, which includes one or more processors for calling and executing instructions stored in memory, thereby causing the method described in the embodiments of this application to be executed. The chip system may be composed of chips or may include chips and other discrete devices.

[0144] The chip system may include input circuits or interfaces for transmitting information or data, and output circuits or interfaces for receiving information or data.

[0145] According to the method provided in the embodiments of this application, this application also provides a computer program product, which includes: computer program code, which, when run on a computer, causes the computer to execute the various steps or processes executed by the network device or terminal device in any of the foregoing method embodiments.

[0146] According to the method provided in the embodiments of this application, this application also provides a computer-readable storage medium storing program code, which, when run on a computer, causes the computer to execute the various steps or processes executed by the network device or terminal device in any of the foregoing method embodiments.

[0147] The computer-readable storage medium may be the aforementioned volatile memory or non-volatile memory, or it may include both volatile memory and non-volatile memory.

[0148] In the embodiments of this application, the terms and English abbreviations are exemplary examples given for ease of description and should not be construed as limiting the application in any way. This application does not preclude the possibility of defining other terms that can achieve the same or similar functions in existing or future agreements.

[0149] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. The computer program product includes one or more computer instructions. When these computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated.

[0150] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

Claims

1. A tube current modulation method, characterized by, The method includes: Acquire a target image and obtain the segmentation result of the target object in the target image, wherein the target image is a three-dimensional image and includes the target object; Based on the segmentation results of the target image and the target object, the scanning range and scanning center point of the scanning device are determined. The scanning device is a device that scans the entity object corresponding to the target object to acquire the target image. The scanning center is a point on the central axis of the target object. Based on the scanning range and the scanning center point, a tube current modulation curve is obtained; the tube current modulation curve is used to adjust the tube current of the scanning device. The step of obtaining the tube current modulation curve based on the scanning range and the scanning center point includes: Determine the equivalent value of each position in the scanning range; wherein, the equivalent value of the first position indicates the equivalent thickness value of the scanning ray emitted by the scanning device from the first position to the scanning center point, the equivalent value of the first position is related to the voxel information of the first position in the target image, and the first position is any one of the positions; The tube current modulation curve is obtained based on the equivalent values ​​at each of the aforementioned locations.

2. The method according to claim 1, characterized in that, Determining the equivalent value of the first position includes: Based on the voxel information between the first position and the scanning center point, and the target correspondence, the equivalent value of the first position is determined; The target correspondence indicates the correspondence between the equivalent value of the first position and the voxel information.

3. The method according to claim 2, characterized in that, If the voxel information includes N voxels on the scanning ray penetration path, where N is a positive integer, the length of each voxel in the scanning ray penetration path, and the linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the degree of attenuation when the scanning ray passes through the structure corresponding to that voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center. The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes: Based on the voxel information and formula (1), the equivalent value of the first position is determined: Among them, WET ( x, y, z ) represents the equivalent value at the first position, and N represents the number of voxels along the path of the scanning ray. μ i For the first i Linear decay coefficient of individual units; μ 水 Δ is the attenuation coefficient of water under a preset voltage; d i For the first i The length of an individual element along the path of the scanning ray.

4. The method according to claim 2, characterized in that, If the voxel information includes N voxels on the scanning ray penetration path, the voxel value of each voxel in the N voxels, and the length of each voxel on the scanning ray penetration path, the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center; The step of determining the equivalent value of the first position based on the voxel information between the first position and the scan center point, and the target correspondence, includes: Based on the voxel information and formula (2), the equivalent value of the first position is determined: Among them, WET ( x, y, z ) is the equivalent value of the first position, N is the number of voxels in the scanning ray penetration path, HU i For the first i voxel value, Δ d i For the first i The length of an individual element along the path of the scanning ray.

5. The method according to claim 1, characterized in that, The process of obtaining the tube current modulation curve based on the equivalent values ​​at each of the aforementioned positions includes: Based on the equivalent values ​​at each location, the tube current value at each location is determined. Specifically, the tube current value at the first position is determined based on the equivalent value at the first position, and the tube current value at the first position is positively correlated with the equivalent value at the first position. Based on the tube current values ​​at each location, the tube current modulation curve is obtained.

6. The method according to claim 5, characterized in that, Determining the tube current value at the first position based on the equivalent value at the first position includes: Based on the equivalent value at the first position and formula (3), the tube current value at the first position is determined: in, mA(x, y, z) The tube current value at the first position, WET ( x, y, z () is the equivalent value of the first position. mA base Based on the baseline value preset by the scanning protocol, the mA base A number greater than 0 and less than 1; WET base This is a reference equivalent value preset based on the scanning protocol. k The modulation index is preset, and k is greater than 0. f 组织 As a correction factor, and f 组织 Greater than 0.

7. The method according to claim 1, characterized in that, The equivalent value of the first position is a value in the first coordinate system. Determining the tube current value at the first position based on the equivalent value of the first position includes: Based on the equivalent value of the first position, the initial tube current value of the first position is determined; the initial tube current value of the first position indicates the tube current value of the first position in the first coordinate system. Based on the transformation relationship between the first coordinate system and the second coordinate system, the tube current value at the first position is determined; the tube current value at the first position is the tube current value in the second coordinate system. Wherein, the first coordinate system is the DICOM coordinate system for medical digital imaging and communication, and the origin of the first coordinate system is the scanning center point; the second coordinate system is the IEC coordinate system.

8. A tube current modulation device, characterized in that, The device includes: The first acquisition unit is used to acquire a target image and acquire a segmentation result of a target object in the target image, wherein the target image is a three-dimensional image and the target image includes the target object; The determining unit is used to determine the scanning range and scanning center point of the scanning device based on the target image and the segmentation result of the target object. The scanning device is a device that scans the entity object corresponding to the target object to acquire the target image. The scanning center is a point on the central axis of the target object. The second acquisition unit is used to acquire a tube current modulation curve based on the scanning range and the scanning center point; the tube current modulation curve is used to adjust the tube current of the scanning device. Based on the scanning range and the scanning center point, a tube current modulation curve is obtained; the tube current modulation curve is used to adjust the tube current of the scanning device. The step of obtaining the tube current modulation curve based on the scanning range and the scanning center point includes: Determine the equivalent value of each position in the scanning range; wherein, the equivalent value of the first position indicates the equivalent thickness value of the scanning ray emitted by the scanning device from the first position to the scanning center point, the equivalent value of the first position is related to the voxel information of the first position in the target image, and the first position is any one of the positions; The tube current modulation curve is obtained based on the equivalent values ​​at each of the aforementioned locations.

9. A computationally readable storage medium, characterized in that, A series of instructions are stored, which, when executed by a processor, implement the tube current modulation method as described in any one of claims 1-7.

Images