Tube current modulation method and device and medium

Abstract

The embodiment of the invention provides a tube current modulation method and device and a medium, and is applied to the technical field of image equipment. The method comprises the steps of determining a scanning range and a scanning center point of a scanning device based on a target image and a segmentation result of a target object in the target image, and obtaining a tube current modulation curve based on the scanning range and the scanning center point of the scanning device through the target image and the segmentation result of the target object. And the scanning current of the scanning equipment is adjusted based on the tube current modulation curve. Therefore, the scanning parameters are dynamically adjusted in image guidance, so that the quality of the image scanned by the scanning equipment is improved. The target image and the segmentation result of the target object in the target image adopted in the embodiment of the invention can accurately reflect the profile structure of the target object, and compared with a two-dimensional positioning image, the thickness difference of the overlapped objects can be effectively distinguished, so that the tube current modulation curve is more accurately generated.

Description

Technical Field

[0001] The present application relates to the technical field of imaging equipment, and in particular to a tube current modulation method, device and medium. Background Art

[0002] With the rapid development of computer and imaging equipment technology, image guidance technology is becoming increasingly important. Image guidance refers to a technology that accurately locates based on real-time or near real-time images, and guides the scanning equipment to scan the target object according to the positioning position. However, current image guidance mostly uses cone-beam computed tomography technology, and its scanning parameters, such as scanning voltage and scanning current (also called tube current), are usually fixed values ​​or manually preset values, which is not conducive to reducing the scanning radiation dose of the scanning equipment, and will lead to poor image quality scanned by the scanning equipment. For example, some areas of the image may be overexposed or underexposed, resulting in poor image positioning accuracy, thereby affecting the image guidance effect. How to dynamically adjust the scanning parameters in image guidance to improve the image quality obtained by the scanning equipment, thereby improving the positioning accuracy and image guidance effect, and reducing the radiation dose, has become a technical problem to be solved. Summary of the Invention

[0003] The embodiments of the present application provide a tube current modulation method, device, and medium, which can dynamically adjust scanning parameters during image guidance, thereby improving the image quality obtained by the scanning device, thereby improving positioning accuracy and image guidance effect, and reducing radiation dose.

[0004] In a first aspect, an embodiment of the present application provides a tube current modulation method, the method comprising:

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

[0006] Determining a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, wherein the scanning device instructs a device to scan a physical object corresponding to the target object to acquire the target image;

[0007] A tube current modulation curve is acquired 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.

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

[0009] Determining an equivalent value for each position in the scanning range; wherein the equivalent value for a first position indicates an equivalent thickness value of a scanning ray emitted by the scanning device from the first position to the scanning center point, and the equivalent value for the first position is associated with voxel information of a first position of the first position in the target image, the first position being any one of the various positions;

[0010] The tube current modulation curve is obtained based on the equivalent values ​​of the various positions.

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

[0012] determining an equivalent value of the first position according to voxel information between the first position and the scanning center point and a target correspondence relationship;

[0013] The target correspondence relationship indicates a correspondence relationship 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 a linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the attenuation degree of the scanning ray when passing through the structure corresponding to the voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0015] The determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes:

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

[0017]

[0018] Wherein, WET(x, y, z) is the equivalent value of the first position, N is the number of voxels on the scanning ray penetration path, μ i is the linear attenuation coefficient of the i-th voxel; μ 水 is the attenuation coefficient of water at the preset voltage; Δd i is the length of the i-th voxel on the scanning ray penetration path.

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

[0020] The determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes:

[0021] According to 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 of the first position, N is the number of voxels on the scanning ray penetration path, HUi is the voxel value of the i-th voxel, Δd i is the length of the i-th voxel on the scanning ray penetration path.

[0024] Optionally, acquiring the tube current modulation curve based on the equivalent values ​​of the respective positions includes:

[0025] determining the tube current value at each position based on the equivalent value at each position;

[0026] wherein, based on the equivalent value of the first position, the tube current value of the first position is determined, and the tube current value of the first position is positively correlated with the equivalent value of the first position;

[0027] The tube current modulation curve is obtained based on the tube current values ​​at the various positions.

[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 of the first position and formula (3), the tube current value of the first position is determined:

[0030]

[0031] Wherein, 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, mA base The mA is the reference value preset based on the scanning protocol. base A number greater than 0 and less than 1; WET base is a reference equivalent value preset based on the scanning protocol, k is a preset modulation index, and k is greater than 0, f 组织 is the correction factor, and f 组织 Greater than 0.

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

[0033] determining an initial tube current value at the first position based on the equivalent value of the first position; the initial tube current value at the first position indicates a tube current value at the first position in the first coordinate system;

[0034] determining a tube current value at the first position according to a conversion relationship between the first coordinate system and the second coordinate system; the tube current value at the first position is the tube current value of the second coordinate system;

[0035] The first coordinate system is a Digital Imaging and Communications in Medicine (DICOM) coordinate system, and the origin of the first coordinate system is the scanning center point; the second coordinate system is an International Electrotechnical Commission (IEC) coordinate system.

[0036] In a second aspect, an embodiment of the present application provides a tube current modulation device, the device comprising:

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

[0038] A determining unit, configured to determine a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, wherein the scanning device instructs a device to scan a physical object corresponding to the target object and acquire the target image;

[0039] The second acquisition unit is configured 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] In a third aspect, an embodiment of the present application provides a computer program product, which includes: a computer program (also referred to as code, or instructions), which, when executed, enables a computer to execute a method in any possible implementation of any of the above aspects.

[0041] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program (also referred to as code, or instructions) that, when run on a computer, enables the computer to execute a method in any possible implementation of any of the above aspects.

[0042] In a fifth aspect, embodiments of the present application provide a chip system comprising one or more processors configured to retrieve and execute instructions stored in a memory, thereby executing the method of any of the above aspects or any possible implementations of each aspect. The chip system may be composed of a chip or may include a chip and other discrete devices.

[0043] Embodiments of the present application provide a tube current modulation method, device, and medium. This method uses a target image and segmentation results of a target object in the target image to determine the scanning range and scanning center point of a scanning device based on the target image and the segmentation results. Based on the scanning range and scanning center point, a tube current modulation curve is obtained, and the scanning current of the scanning device is adjusted based on the tube current modulation curve. Thus, embodiments of the present application utilize tube current modulation to dynamically adjust the tube current of a scanning device based on the thickness, density, and attenuation characteristics of the target object, thereby dynamically adjusting scanning parameters during image guidance and improving the image quality obtained by the scanning device. Furthermore, the target image used in embodiments of the present application is a three-dimensional image and 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 to using a two-dimensional scout image, it can effectively distinguish thickness differences of overlapping objects, thereby more accurately generating a tube current modulation curve, thereby improving positioning accuracy and image guidance effectiveness, and further reducing the radiation dose of the scanning device. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0045] Figure 1 A flow chart of a tube current modulation method provided in an embodiment of the present application;

[0046] Figure 2 A schematic diagram of a set of positioning CT images and target object segmentation results provided in an embodiment of the present application;

[0047] Figure 3 A schematic diagram of a scanning range and a scanning center point corresponding to a physical object scanned by a CT device provided in an embodiment of the present application;

[0048] Figure 4 A schematic diagram of a structure in which a scanning device in a first position emits a scanning ray through a target object provided by an embodiment of the present application;

[0049] Figure 5 This is a schematic structural diagram of a tube current modulation device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0050] In order to help those skilled in the art better understand the present invention, the following will clearly and completely describe the technical solutions in this embodiment with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

[0051] First, the technical terms involved in the embodiments of the present application are introduced.

[0052] Tube Current Modulation (TCM) technology dynamically adjusts the tube current of the scanning device during the scanning process based on the thickness, density, and attenuation characteristics of the scanned object. For example, TCM can dynamically adjust the tube current of the scanning radiation during computed tomography (CT) scanning. Using real-time or pre-calculated attenuation coefficients, this technology automatically adjusts the tube current for each scan layer or scan line, thereby improving the image quality of the scanning device. For CT equipment, this can also reduce the amount of radioactive agents used.

[0053] The principle behind TCM technology is that when a scanner scans, the scanning rays generate a specific current (referred to as tube current). These rays pass through the target object and are received by the detector, producing a scanned image. Before and during scanning, the scanner 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 target objects.

[0054] However, current scanning tube currents are fixed or manually set based on preset conditions. This means the tube current cannot be dynamically adjusted to the target object's needs. For example, when scanning thick objects, a low tube current can't guarantee penetration. This results in poor image quality, with some areas of the image being over- or under-exposed, leading to poor positioning accuracy and, consequently, poor image guidance.

[0055] In view of this, embodiments of the present application provide a tube current modulation method. This method uses a target image and a segmentation result of a target object in the target image to determine the scanning range and scanning center point of a scanning device based on the target image and the segmentation result of the target object. Based on the scanning range and scanning center point of the scanning device, a tube current modulation curve is obtained, and the scanning current of the scanning device is adjusted based on the tube current modulation curve. Thus, embodiments of the present 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, 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 embodiments of the present application is a three-dimensional image and includes the target object. Using the target image and the segmentation result of the target object in the target image can accurately reflect the cross-sectional structure of the target object. Compared to using a two-dimensional scout image, it can effectively distinguish thickness differences of overlapping tissues, thereby more accurately generating a tube current modulation curve, thereby improving positioning accuracy and image guidance effectiveness.

[0056] The following is a detailed and complete discussion of the tube current modulation method and the application scenarios of the tube current modulation method provided in the embodiments of the present application in conjunction with the accompanying drawings.

[0057] First, the application scenario of the tube current modulation method provided by the embodiment of the present application is introduced.

[0058] Exemplarily, the tube current modulation method can be applied to a computing device that can acquire a target image and a segmentation result of a target object in the target image, and 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 the embodiment of the present application is also used to connect to a 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 the embodiments of the present application may be a desktop computer, a server, a cloud server, a mobile terminal, or other device with computing functions, which is not specifically limited in the embodiments of the present application.

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

[0062] Attachment Figure 1 This is a flow chart of a tube current modulation method provided in an embodiment of the present application. The method includes the following steps S110 to S130:

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

[0064] The target object corresponds to the physical object and refers to the display information of the physical object in the target image. In the embodiment of the present application, the physical object refers to the object that needs to be scanned by the scanning device. For example, the physical object can be a cultural relic, luggage, or a patient's organ, etc., which is not specifically limited in the embodiment of the present application.

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

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

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

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

[0069] It can be understood that since the CT image obtained after scanning by the CT device is a two-dimensional image, that is, the computing device can reconstruct the positioning CT image, obtain a three-dimensional target image, and obtain the contour display result of the target object in the target image. It can be understood that the contour display result is three-dimensional irregular volume data.

[0070] Exemplary description, attached Figure 2 This is a schematic diagram of a set of positioning CT images and target object segmentation results provided in an embodiment of the present application. Figure 2 As shown in the figure, the group of positioning CT images and target object segmentation results are shown from three angles. Figure 2 (a) shows a positioning CT image at a first angle and a contour display result of a target object in the positioning CT image at the first angle. Figure 2 (b) shows the positioning CT image at the second angle and the contour display result of the target object in the positioning CT image at the second angle. Figure 2 (c) shows the positioning CT image at the third angle and the contour display result of the target object in the positioning CT image at the third angle.

[0071] like Figure 2 As shown, the computing device can obtain a three-dimensional positioning CT image by reconstructing the positioning CT images of the three angles and the target object segmentation results.

[0072] In an embodiment of the present application, the computing device first obtains the target image and the segmentation results of the target object, and then processes the segmentation results of the target image and the target object to obtain the tube current modulation curve.

[0073] S120. Determine a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, wherein the scanning device instructs a device to scan a physical object corresponding to the target object and acquire the target image.

[0074] The scanning range is the three-dimensional area covered by the scanning device when scanning a physical object. The scanning range is defined by the starting point and the ending point of the scan. In the embodiment of the present application, the boundaries of the scanning range clearly indicate the maximum and minimum coordinate positions that the scanning device can scan.

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

[0076] Exemplary description, attached Figure 3 The present invention provides a schematic diagram of a scanning range and a scanning center point corresponding to a CT device scanning a physical object. Figure 3 As shown, the scanning center point is located at the center of the chest of the physical object, and the scanning range covers the entire chest, wherein 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 an embodiment of the present application, the computing device may 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. Next, based on the segmentation results of the target object in the localization CT image, the computing device can digitally identify the outline coordinates of the target object. Based on the location of the target object and the segmentation results, the computing device can then generate a three-dimensional bounding box encompassing the target object and its surrounding key structures. This three-dimensional bounding box serves as the scanning range. The center point of the target object region is determined as the scanning center point.

[0079] It can be understood that in the embodiment of the present 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 . 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.

[0081] In the embodiment of the present application, the computing device determines an equivalent value for each position within the scanning range based on the scanning range and the scanning center point of the scanning device. Based on the equivalent values ​​for each position, the tube current value at each position is determined. To better illustrate the equivalent values ​​for 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 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, and is related to the voxel information of the first position in the target image.

[0083] The voxel information at the first position is used to describe the voxel situation at the first position, including but not limited to the N voxels on the scanning ray penetration path composed of 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 attenuation degree of the scanning ray when passing through the structure corresponding to the voxel. Wherein, N is a positive integer. In addition, the voxel information at the first position may also include the voxel coordinates of each voxel, the CT value contained in the voxel (in HU), etc., which are not specifically limited in the embodiments of the present application.

[0084] Since voxel information can directly reflect the density and geometric characteristics of the target object at that position, the equivalent value of the first position can be accurately determined through the voxel information of the first position, compared with relying only on the frontal two-dimensional projection image or the lateral two-dimensional projection image.

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

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

[0087]

[0088] Wherein, WET(x, y, z) is the equivalent value of the first position, N is the number of voxels on the scanning ray penetration path, μ i is the linear attenuation coefficient of the i-th voxel; μ 水 is the attenuation coefficient of water at the preset voltage (for example, when the preset voltage is 120KV, μ 水 0.19 / cm); Δd i is the length of the i-th voxel on the scanning ray penetration path, which is obtained by calculation using a geometric projection model.

[0089] For example, Figure 4 The figure shows a schematic diagram of a structure in which a scanning device in a first position provides a scanning ray through a target object. Figure 4 As shown, the scanning device is a CT device (also known as a CT tube), the position of the scanning device is a first position (x, y, z), and a scanning ray is emitted from the first position and passes through the scanning center point as a scanning ray projection path 401. In the embodiment of the present application, the equivalent value of the current position (i.e., the first position) can be determined based on formula (1).

[0090] In another example, since 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, Δd i is the length of the i-th voxel on the scanning ray penetration path.

[0093] In the embodiment of the present application, the computing device may obtain the equivalent value of the first position based on formula (2). For example, continue to refer to Figure 4 As shown, using scanning rays and Figure 4The two intersection points of the target object's contour information are intersection A1 and intersection A2, respectively. These two intersection points constitute the scanning ray penetration path. Based on the CT values ​​of the voxels in the scanning ray penetration path, the equivalent value of the first position can be calculated. The embodiment of the present application adopts the method of formula (2), which has less calculation amount than the method of formula (1), and can significantly improve the calculation speed and calculation accuracy.

[0094] It should be noted that the embodiment of the present application can also obtain the equivalent value of the first position through other methods, which are not specifically limited in the embodiment of the present application.

[0095] Furthermore, after obtaining the equivalent values ​​for each position within the scanning range, the tube current value at each position can be determined based on the equivalent values ​​for each position within the scanning range. For ease of explanation, the first position is still used 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 at the first location is high, meaning the first location is in a high equivalent value region, such as the pelvic bone region, the tube current value at the first location is high, meaning that during scanning, the scanning device uses a high tube current to penetrate the target object. If the equivalent value at the first location is low, meaning the first location is in a low equivalent value region, such as the lung field region, the tube current value at the first location is low, meaning that during scanning, the scanning device uses a low tube current to penetrate the target object. The technology in this embodiment dynamically adjusts the tube current based on the thickness of the target object, effectively improving image quality and reducing radiation dose.

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

[0098]

[0099] Wherein, 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, mA base The mA is the reference value preset based on the scanning protocol. base A number greater than 0 and less than 1; WET base is a reference equivalent value preset based on the scanning protocol, k is a preset modulation index, and k is greater than 0, f 组织 is the correction factor, and f 组织 Greater than 0.

[0100] Furthermore, in the embodiment of the present application, mA baseThe k value can be determined based on a scanning protocol and a shape of a scanning object. The k value can be automatically assigned according to a thickness of the solid object obtained in combination with an outer contour of a segmentation result of the target object. 组织 The f value is used to correct special factors, and is related to a type of the special factors. For example, if the special factors are bone regions, the f value can be between 1.1 and 1.2, and is used to compensate for additional attenuation of high-density bone tissue. Sensitive organs: for example, breast, f 组织 = 0.7, for example, eyes, f 组织 = 0.5 to limit the dose. Further, the f value 组织 The f value is automatically assigned according to a tissue region of a current scan determined based on an intersection of a scanning ray and a contour of the target object.

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

[0102] Further, in the embodiments of the present application, the tube current values at the respective positions are obtained in a Digital Imaging and Communications in Medicine (DICOM) coordinate system, in which an origin is a scanning center point.

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

[0104] It can be understood that the first coordinate system and the second coordinate system have a conversion relationship, and the conversion relationship is fixed. The computing device can convert the tube current values in the first coordinate system into tube current values in the second coordinate system based on the conversion relationship. The tube current in the tube current modulation curve is the tube current in the second coordinate system.

[0105] S140, using the tube current modulation curve to perform tube current modulation

[0106] In the embodiments of the present application, 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 tube current values at different rotation angles in each circle during scanning of the CT device based on the tube current modulation curve at the respective positions, and perform current modulation in a target direction of the solid object in combination with response accuracy of tube current control of the CT device. The target direction can be a Z-axis direction of the second coordinate system, or can be an XY plane of the second coordinate system, and the embodiments of the present application are not specifically limited.

[0108] The tube current modulation method provided in embodiments of the present application uses a target image and a segmentation result of a target object in the target image to determine the scanning range and scanning center point of a scanning device based on the target image and the segmentation result of the target object. Based on the scanning range and scanning center point of the scanning device, a tube current modulation curve is obtained, and the scanning current of the scanning device is adjusted based on the tube current modulation curve. Thus, embodiments of the present 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, thereby dynamically adjusting scanning parameters in image guidance and improving the image quality obtained by the scanning device. Furthermore, the target image used in embodiments of the present application is a three-dimensional image and includes the target object. Using the target image and the segmentation result of the target object in the target image can accurately reflect the cross-sectional structure of the target object. Compared to using a two-dimensional scouting image, it can effectively distinguish thickness differences of overlapping objects, thereby more accurately generating a tube current modulation curve, thereby improving positioning accuracy and image guidance effectiveness.

[0109] In addition, an embodiment of the present application also provides a tube current modulation device.

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

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

[0112] A determining unit 502 is configured to determine a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, the scanning device instructing a device to scan a physical object corresponding to the target object and acquire the target image;

[0113] The second acquisition unit 503 is configured 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 configured to include:

[0115] Determining an equivalent value for each position in the scanning range; wherein the equivalent value for a first position indicates an equivalent thickness value of a scanning ray emitted by the scanning device from the first position to the scanning center point, and the equivalent value for the first position is associated with voxel information of a first position of the first position in the target image, the first position being any one of the various positions;

[0116] The tube current modulation curve is obtained based on the equivalent values ​​of the various positions.

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

[0118] determining an equivalent value of the first position according to voxel information between the first position and the scanning center point and a target correspondence relationship;

[0119] The target correspondence relationship indicates a correspondence relationship 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 a linear attenuation coefficient of each voxel; the linear attenuation coefficient of each voxel indicates the attenuation degree of the scanning ray when passing through the structure corresponding to the voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center;

[0121] The determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes:

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

[0123]

[0124] Wherein, WET(x, y, z) is the equivalent value of the first position, N is the number of voxels on the scanning ray penetration path, μ i is the linear attenuation coefficient of the i-th voxel; μ 水 is the attenuation coefficient of water at the preset voltage; Δd i is the length of the i-th voxel on the scanning ray penetration path.

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

[0126] Determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes:

[0127] According to 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 of the first position, N is the number of voxels on the scanning ray penetration path, HUi is the voxel value of the i-th voxel, Δd i is the length of the i-th voxel on the scanning ray penetration path.

[0130] Optionally, acquiring the tube current modulation curve based on the equivalent values ​​of the respective positions includes:

[0131] determining the tube current value at each position based on the equivalent value at each position;

[0132] wherein, based on the equivalent value of the first position, the tube current value of the first position is determined, and the tube current value of the first position is positively correlated with the equivalent value of the first position;

[0133] The tube current modulation curve is obtained based on the tube current values ​​at the various positions.

[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 of the first position and formula (3), the tube current value of the first position is determined:

[0136]

[0137] Wherein, 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, mA base The mA is the reference value preset based on the scanning protocol. base A number greater than 0 and less than 1; WET base is a reference equivalent value preset based on the scanning protocol, k is a preset modulation index, and k is greater than 0, f 组织 is the correction factor, and f 组织 Greater than 0.

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

[0139] determining an initial tube current value at the first position based on the equivalent value of the first position; the initial tube current value at the first position indicates a tube current value at the first position in the first coordinate system;

[0140] According to a conversion relationship between the first coordinate system and the second coordinate system, a tube current value of the first position is determined; the tube current value of the first position is a tube current value of the second coordinate system.

[0141] The first coordinate is a Digital Imaging and Communications in Medicine (DICOM) coordinate system, and an origin of the first coordinate system is the scanning center point; and the second coordinate system is an International Electrotechnical Commission (IEC) coordinate system.

[0142] The tube current modulation device provided in the embodiments of the present application determines the scanning range and the scanning center point of the scanning device based on the target image and the segmentation result of the target object in the target image, and acquires the tube current modulation curve based on the scanning range and the scanning center point of the scanning device, so as to adjust the scanning current of the scanning device based on the tube current modulation curve. Thus, the embodiments of the present application can dynamically adjust the tube current of the scanning device according to the thickness, density and attenuation characteristics of the target object by using tube current modulation, thereby dynamically adjusting the scanning parameters in image guidance and further improving the image quality obtained by the scanning device. Moreover, the target image adopted in the embodiments of the present application is a three-dimensional image and includes the target object, and the target image and the segmentation result of the target object in the target image can accurately reflect the cross-sectional structure of the target object, can effectively distinguish the thickness difference of overlapping objects relative to the two-dimensional positioning image, and thus can more accurately generate the tube current modulation curve, thereby improving the positioning accuracy and the image guidance effect.

[0143] According to the method provided in the embodiments of the present application, the present application further provides a chip system, which includes one or more processors for calling and running instructions stored in a memory, so that the method provided in the embodiments of the present application is executed. The chip system can be composed of a chip, or can include the chip and other discrete devices.

[0144] The chip system can include an input circuit or interface for sending information or data, and an output circuit or interface for receiving information or data.

[0145] According to the method provided in the embodiments of the present application, the present application further provides a computer program product, which includes computer program codes, when the computer program codes are run on a computer, so that the computer executes each step or process performed by the network device and the terminal device in any of the preceding method embodiments.

[0146] According to the method provided in the embodiments of the present application, the present application further provides a computer readable storage medium, which stores program codes, and when the program codes are executed on a computer, the computer is caused to perform each step or process of the network device and the terminal device in any of the foregoing method embodiments.

[0147] The computer readable storage medium can be the volatile memory or the nonvolatile memory as described above, or can include both the volatile memory and the nonvolatile memory.

[0148] In the embodiments of the present application, each term and English abbreviation is an exemplary example given for convenience of description, and should not constitute any limitation on the present application. The present application does not exclude the possibility of defining other terms capable of achieving the same or similar functions in the existing or future protocols.

[0149] In the foregoing embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated.

[0150] In several embodiments provided in the present application, it should be understood that the disclosed system, device and method can be implemented by other ways. For example, the device embodiments described above are merely illustrative, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or components shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

Claims

1. A tube current modulation method, characterized in that: The method comprises: Acquire a target image and obtain a segmentation result of a target object in the target image, wherein the target image is a three-dimensional image and includes the target object; Determining a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, wherein the scanning device instructs a device to scan a physical object corresponding to the target object to acquire the target image; A tube current modulation curve is acquired 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.

2. The method according to claim 1, characterized in that The acquiring of a tube current modulation curve based on the scanning range and the scanning center point includes: Determining an equivalent value for each position in the scanning range; wherein the equivalent value for a first position indicates an equivalent thickness value of a scanning ray emitted by the scanning device from the first position to the scanning center point, and the equivalent value for the first position is associated with voxel information of a first position of the first position in the target image, the first position being any one of the various positions; The tube current modulation curve is obtained based on the equivalent values ​​of the various positions.

3. The method according to claim 2, characterized in that Determining an equivalent value of the first position, comprising: determining an equivalent value of the first position according to voxel information between the first position and the scanning center point and a target correspondence relationship; The target correspondence relationship indicates a correspondence relationship between the equivalent value of the first position and the voxel information.

4. The method according to claim 3, 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 attenuation degree of the scanning ray when passing through the structure corresponding to the voxel, and the scanning ray penetration path indicates the path of the scanning ray from the first position to the scanning center; The determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes: According to the voxel information and formula (1), the equivalent value of the first position is determined: Wherein, WET(x, y, z) is the equivalent value of the first position, N is the number of voxels on the scanning ray penetration path, μ i is the linear attenuation coefficient of the i-th voxel; μ 水 is the attenuation coefficient of water at the preset voltage; Δd i is the length of the i-th voxel on the scanning ray penetration path.

5. The method according to claim 3, characterized in that If the voxel information includes N voxels on a scanning ray penetration path, a voxel value of each voxel in the N voxels, and a length of each voxel on the scanning ray penetration path, the scanning ray penetration path indicates a path of the scanning ray from the first position to the scanning center; The determining the equivalent value of the first position according to the voxel information between the first position and the scanning center point and the target correspondence relationship includes: According to the voxel information and formula (2), the equivalent value of the first position is determined: Where WET(x, y, z) is the equivalent value of the first position, N is the number of voxels on the scanning ray penetration path, HUi is the voxel value of the i-th voxel, Δd i is the length of the i-th voxel on the scanning ray penetration path.

6. The method according to claim 2, characterized in that The acquiring the tube current modulation curve based on the equivalent values ​​of the respective positions includes: determining the tube current value at each position based on the equivalent value at each position; wherein, based on the equivalent value of the first position, the tube current value of the first position is determined, and the tube current value of the first position is positively correlated with the equivalent value of the first position; The tube current modulation curve is obtained based on the tube current values ​​at the various positions.

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

8. The method according to claim 2, characterized in that: The equivalent value of the first position is a value in a first coordinate system, and determining the tube current value of the first position based on the equivalent value of the first position includes: determining an initial tube current value at the first position based on the equivalent value of the first position; the initial tube current value at the first position indicates a tube current value at the first position in the first coordinate system; determining a tube current value at the first position according to a conversion relationship between the first coordinate system and the second coordinate system; the tube current value at the first position is the tube current value of the second coordinate system; The first coordinate system is a Digital Imaging and Communications in Medicine (DICOM) coordinate system, and the origin of the first coordinate system is the scanning center point; the second coordinate system is an International Electrotechnical Commission (IEC) coordinate system.

9. A tube current modulation device, characterized in that: The device comprises: a first acquiring unit, configured to acquire a target image and a segmentation result of a target object in the target image, wherein the target image is a three-dimensional image and includes the target object; A determining unit, configured to determine a scanning range and a scanning center point of a scanning device based on the segmentation results of the target image and the target object, wherein the scanning device instructs a device to scan a physical object corresponding to the target object and acquire the target image; The second acquisition unit is configured 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.

10. A computer-readable storage medium, characterized in that A series of instructions are stored, and when the instructions are executed by a processor, the tube current modulation method according to any one of claims 1 to 8 is implemented.

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