A method, system, device, and storage medium for angularly calibrating a post-reconstruction medical image of a slip ring

Abstract

This invention relates to the field of CT technology, and more particularly to a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration. The system includes: a CT system generating an exposure command and sending it to a stator control board via a host computer; the stator control board generating a rotation command based on the exposure command and sending it to a motor; the motor acquiring an initial angle α based on the rotation command; the stator control board calculating pulse encoders based on the initial angle α and the exposure command; a motion control board generating control commands based on the pulse encoders and sending them to a driver; and the driver outputting a pulse signal f based on the control commands. n The slip ring will handle each pulse signal f n The angle information is sent to the detector subsystem; the rotor control board sends pulse number encoders to the detector subsystem, which, upon receiving the pulse number encoders, acquires the projection data of the X-ray tube and outputs the projection data in the raw data to obtain the reconstructed data; the host computer reconstructs the medical image based on the reconstructed data. This provides an image reconstruction method to reduce artifacts.

Description

Technical Field

[0001] This invention relates to the field of CT technology, and in particular to a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration. Background Technology

[0002] Currently, CT scanners generate projection information at various angles through rotating X-ray tubes, and the reconstruction subsystem of the CT scanner reconstructs images by matching the angle and projection information. The angle information in current CT scanners is recorded in the holes of the slip ring, which is essentially non-expandable. The slip ring of the CT scanner also has a ring of coded holes for recording angle information. When the CT scanner's rotor rotates for exposure, the data acquisition system records the projection information and the coded holes under this projection (used to calculate angle information). Existing technology uses a coded strip and coded plate integrated into the slip ring to detect the rotational position. However, over time, the holes in the coded strip are easily clogged by dust, or the accumulated dust causes the signal recognized by the coded plate to not meet specifications, ultimately leading to image artifacts; the coded strip requires frequent maintenance, resulting in increased maintenance costs; the coded strip is integrated into the slip ring, and the installation of the coded plate after slip ring assembly is complex and requires high precision, making debugging complex and inefficient; inaccurate installation will lead to image artifacts; the coded strip has weak resistance to impact, vibration, and dust; and the coded strip has weak resistance to contamination from various common industrial chemicals.

[0003] The correct prevention of angle information will directly affect the quality of the reconstructed image. In particular, when two sets of scans need to be reconstructed by matching angles, inconsistent angle information will cause a certain offset in the projection information received by the detector, resulting in artifacts.

[0004] In summary, the technical problem that this invention actually solves is how to provide an image reconstruction method to reduce artifacts. Summary of the Invention

[0005] In order to overcome the above-mentioned technical defects, the purpose of this invention is to provide a method, system, device and storage medium for reconstructing medical images after slip ring angle calibration, and to provide an image reconstruction method to reduce artifacts.

[0006] This invention discloses a method for reconstructing medical images after slip ring angle calibration, comprising the following steps:

[0007] Exposure commands are generated based on the CT equipment and sent to the stator control board via the host computer;

[0008] The stator control board generates a rotation command based on the exposure command and sends the rotation command to the motor.

[0009] The motor obtains the starting angle α according to the rotation command, and the motor feeds back the starting angle α to the stator control board;

[0010] The stator control board calculates the number of pulse encoders required by the motor for this exposure based on the starting angle α and the exposure command, and sends the number of pulse encoders to the rotor control board and the motion control board respectively.

[0011] The motion control board generates control commands based on the pulse count encoders and sends the control commands to the driver.

[0012] The driver outputs a pulse signal equal to the number of encoders according to the control command. The slip ring responds to the pulse signal Will be with each pulse signal The corresponding angle information is sent to the detector subsystem;

[0013] The rotor control board simultaneously sends pulse number encoders to the detector subsystem. When the detector subsystem receives the pulse number encoders, the detector acquires the projection data of the X-ray tube, and records the angle information in the projection data. The detector subsystem outputs the projection data in the original data to obtain the reconstructed data.

[0014] The detector subsystem transmits the reconstructed data to the host computer via the rotor control board, and the host computer's reconstruction subsystem reconstructs the medical image based on the reconstructed data.

[0015] Preferably, when the motor obtains the starting angle α according to the rotation command, the motor is an ABZ incremental encoder, and the ABZ incremental encoder generates a Z-direction signal each time it passes the origin;

[0016] When the angle at which each Z-axis signal is generated is defined as β, and the number of pulses (encoders) received by the motor from angle β to the initial angle α is f, the calculation formula is as follows:

[0017]

[0018] Obtain α, where α is the initial angle of the motor rotor for each revolution; β is the angle at which the motor generates a Z-axis signal; allEncoders is the total number of encoders, which is equal to 4 × encodersMin, where encodersMin is the minimum number of encoders; and the symbol % represents the remaining number of encoders.

[0019] Preferably, when the stator control board calculates the number of encoders required by the motor for this exposure based on the starting angle α and the exposure command, it uses the following formula:

[0020]

[0021] Obtain the number of pulses encoders, where encodersMin is the minimum number of pulses encoders.

[0022] Preferably, when the detector subsystem outputs projection data into the original data to obtain reconstructed data, it uses the following calculation formula:

[0023]

[0024] Obtain reconstruction data, including The angle information when the detector acquires a certain projection data of the X-ray tube.

[0025] In view of this, a second objective of the present invention is to provide a system employing the above-described method, comprising:

[0026] Exposure command generation module: used to generate exposure commands based on CT equipment and send the exposure commands to the stator control board via the host computer;

[0027] Rotation command generation module: used to customize the control board to generate rotation commands based on exposure commands and send the rotation commands to the motor;

[0028] Acquisition module: used by the motor to acquire the starting angle α according to the rotation command, and the motor feeds back the starting angle α to the stator control board;

[0029] The pulse count encoder module is used by the stator control board to calculate the number of pulse encoders required by the motor for this exposure based on the starting angle α and the exposure command. The stator control board then sends the calculated pulse count encoders to the rotor control board and the motion control board respectively.

[0030] Control command generation module: Used by the motion control board to generate control commands based on the number of pulse encoders and send the control commands to the driver;

[0031] Output pulse signal Module: Used by the driver to output a pulse signal equal to the number of pulse signal encoders according to control commands. The slip ring responds to the pulse signal Will be with each pulse signal The corresponding angle information is sent to the detector subsystem;

[0032] The module for acquiring reconstructed data is used by the rotor control board to simultaneously send pulse number encoders to the detector subsystem. When the detector subsystem receives the pulse number encoders, the detector acquires the projection data of the X-ray tube, and the angle information is recorded in the projection data. The detector subsystem outputs the projection data in the original data to acquire the reconstructed data.

[0033] Reconstruction module: The detector subsystem transmits reconstruction data to the host computer via the rotor control board, and the host computer's reconstruction subsystem reconstructs the medical image based on the reconstruction data.

[0034] In view of this, a third objective of the present invention is to provide a CT device, wherein the CT device is provided with at least one system as described above.

[0035] In view of this, a third objective of the present invention is to provide a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method described above.

[0036] After adopting the above technical solution, compared with the prior art, the beneficial effect of the present invention is that it provides an image reconstruction method to reduce artifacts. By calibrating the angle of each circle to make the error of each circle zero, the accuracy of the angle information of each circle is maintained, thereby reducing artifacts, thereby reducing the frequency of maintenance of the coding band and the installation of the coding board after installing the slip ring assembly, thereby reducing maintenance costs. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the process steps for reconstructing medical images after slip ring angle calibration according to the present invention;

[0038] Figure 2 This is a schematic diagram illustrating the workflow of a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration according to the present invention.

[0039] Figure 3 This is a schematic diagram illustrating the definition of the origin of angle information for a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration, according to the present invention.

[0040] Figure 4 This is a schematic diagram illustrating an example of a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration according to the present invention.

[0041] Figure 5 This is a schematic diagram of the error of the driver for a method, system, device, and storage medium for reconstructing medical images after slip ring angle calibration, according to the present invention.

[0042] Figure label:

[0043] 1 is the host computer, 2 is the stator control board, 3 is the rotor control board, 4 is the motor, 5 is the detector subsystem, 6 is the motion control board, 7 is the driver, 8 is the slip ring, and 9 is the X-ray tube. Detailed Implementation

[0044] The advantages of the present invention will be further illustrated below with reference to the accompanying drawings and specific embodiments.

[0045] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this disclosure. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this disclosure as detailed in the appended claims.

[0046] The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. The singular forms “a,” “the,” and “the” as used in this disclosure and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0047] It should be understood that although the terms first, second, third, etc., may be used in this disclosure to describe various information, such information should not be limited to these terms. These terms are used only to distinguish information of the same type from one another. For example, without departing from the scope of this disclosure, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to determination."

[0048] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0049] In the description of this invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two components. They can be direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0050] In the following description, suffixes such as "module," "part," or "unit" used to denote elements are used only for the convenience of the description of the invention and have no specific meaning in themselves. Therefore, "module" and "part" can be used interchangeably.

[0051] See Figures 1 to 5 As shown, this embodiment provides a method for reconstructing medical images after angle calibration of slip ring 8, including the following steps:

[0052] S100: Based on the CT equipment, an exposure command is generated, and the exposure command generated by the CT equipment is sent to the stator control board 2 through the host computer 1 of the CT equipment. The stator control board 2 receives the exposure command sent by the host computer 1.

[0053] S200: After receiving the exposure command, the stator control board 2 will generate a rotation command and send the generated rotation command to the motor 4. The motor 4 receives the rotation command sent by the stator control board 2.

[0054] S300: After the motor 4 receives the rotation command issued by the stator control board 2, the motor 4 obtains the starting angle α according to the rotation command, and the motor 4 feeds back the starting angle α to the stator control board 2.

[0055] S400: The stator control board 2 calculates the number of pulse encoders that the motor 4 needs to generate in this exposure based on the starting angle α fed back by the motor 4 and the exposure command, and the stator control board 2 sends the number of pulse encoders to the rotor control board 3 and the motion control board 6 respectively.

[0056] S500: After receiving the pulse number encoders, the motion control board 6 generates control commands based on the pulse number encoders, and the control board sends the control commands to the driver 7;

[0057] S600: Driver 7 outputs a pulse signal equal to the number of encoders according to the control command. Slip ring 8 according to pulse signal Will be with each pulse signal The corresponding angle information is sent to detector subsystem 5;

[0058] S700: When the rotor control board 3 receives the pulse number encoders sent by the stator control board 2, it will quietly send the pulse number encoders to the detector subsystem 5. At this time, when the detector subsystem 5 receives the pulse number encoders, the detector collects the projection data of the X-ray tube. The angle information is recorded in the projection data, and the detector subsystem 5 outputs the projection data in the original data to obtain the reconstructed data.

[0059] S800: The detector subsystem 5 transmits the reconstructed data to the host computer 1 of the CT equipment via the rotor controller. The host computer 1 will then reconstruct the medical image based on the reconstructed data, thereby reducing artifacts.

[0060] It should be noted that when motor 4 obtains the initial angle α according to the rotation command, motor 4 includes, but is not limited to, an ABZ incremental encoder. The ABZ incremental encoder generates a Z-axis signal each time it passes the origin. When the angle at which each Z-axis signal is generated is defined as β, and the number of pulses received by motor 4 from angle β to the initial angle α (encoders) is f, the calculation formula is used:

[0061]

[0062] To obtain the initial angle α, where α is the initial angle of each rotation of the rotor of motor 4; β is the angle of each Z-axis signal generated by motor 4; allEncoders is the total number of encoders, which is equal to 4 × encodersMin, where encodersMin is the minimum number of encoders, and the % symbol is the remainder symbol.

[0063] It should be noted that when the stator control board 2 calculates the number of encoders required by the motor 4 for this exposure based on the initial angle α and the exposure command, it uses the following formula:

[0064]

[0065] Obtain the number of pulses encoders, where encodersMin is the minimum number of pulses encoders.

[0066] It should be noted that when the detector subsystem 5 outputs projection data into the raw data to obtain reconstructed image data, it uses the following calculation formula:

[0067]

[0068] To obtain reconstruction data, among which The angle information when the detector acquires a certain projection data of the X-ray tube.

[0069] For details, please refer to Figure 2 The diagram shows a workflow illustration of a method, system, device, and storage medium for reconstructing medical images after angle calibration of a slip ring 8 according to the present invention. Figure 2 During the process, the CT scanner will generate exposure commands. These commands are generated only when medical personnel operate the CT scanner. After the CT scanner generates the exposure commands, the host computer 1 sends the relevant scanning parameters contained in the exposure commands to the stator control board 2. (See also...) Figure 3As shown, in this invention, the position 0° of the CT tube 9 in the CT equipment is defined as the system angle 0°. First, the stator control board 2 receives the exposure command and generates a rotation command. The stator control board 2 then sends the rotation command to the motor 4. The encoders are defined as the number of pulses generated per revolution of the rotor, i.e., the pulses generated by the pulse simulation interface of the driver 7. The larger the encoders, i.e., the more pulses generated per unit angle, the higher the sampling resolution of the rotor angle, and the more accurate the rotor angle positioning. Figure 4 In this code, encoders=6. It should be noted that encodersMin is the minimum number of pulses, and 4 × encodersMin is the maximum number of pulses. Motor 4 uses an ABZ incremental encoder, which generates exactly one Z-axis signal each time motor 4 passes the origin. That is, motor 4 generates only one Z-axis signal per revolution, and the angle position of each generated Z-axis signal is consistent and highly accurate, with no cumulative error. Figure 5 As shown. Let the Z-direction signal be β, and the number of pulses received by motor 4 from β to α be f. Then α can be obtained using the following formula: The formula is:

[0070]

[0071] The % symbol is the bitwise AND symbol, and allEncoders = 4 × encoders.

[0072] Motor 4 feeds back the starting angle α to stator control board 2 in real time. Stator control board 2 calculates the number of pulses (encoders) required from motor 4 for this rotational exposure based on the following formula:

[0073] .

[0074] After analyzing and processing the pulse encoders on the stator control board 2, the pulse encoders are forwarded to the rotor control board 3 and the motion control board 6. Upon receiving the pulse encoders, the motion control board 6 generates control commands, and the pulse simulation interface of the driver 7 outputs a pulse signal equal to the number of pulse encoders. At this time, slip ring 8 will be in each pulse signal The corresponding angle information is forwarded to the detector subsystem 5. Simultaneously, the rotor control board 3 forwards the pulse number encoders to the detector subsystem 5. The detector acquires the projection data (views data) of the X-ray tube and records the angle information. And output them one by one in the original data to obtain the reconstructed data, that is, through the calculation formula:

[0075]

[0076] Messenger correspond Finally, the reconstruction data will be transmitted to the host computer 1 via the rotor control board 3, and the host computer 1 will reconstruct the medical image using the reconstruction data.

[0077] It should be noted that this embodiment also provides a system using the method provided in the above embodiments, including:

[0078] Exposure command generation module: used to generate exposure commands based on the CT system and send the exposure commands to the stator control board 2 via the host computer 1;

[0079] Rotation command generation module: used to customize the control board to generate rotation commands based on exposure commands and send the rotation commands to motor 4;

[0080] Acquisition module: used by motor 4 to acquire the starting angle α according to the rotation command, and motor 4 feeds back the starting angle α to stator control board 2;

[0081] The pulse count encoder module is used by the stator control board to calculate the number of pulse encoders required by motor 4 for this exposure based on the starting angle α and the exposure command. The stator control board then sends the calculated pulse count encoders to the rotor control board 3 and the motion control board 6 respectively.

[0082] Control command generation module: used by motion control board 6 to generate control commands based on pulse number encoders and send the control commands to driver 7;

[0083] Output pulse signal Module 7: Used by driver 7 to output pulse signals equal to the number of pulse signal encoders according to control commands. Slip ring 8 according to pulse signal Will be with each pulse signal The corresponding angle information is sent to detector subsystem 5;

[0084] The module for acquiring reconstruction data is used by the rotor control board 3 to simultaneously send pulse number encoders to the detector subsystem 5. When the detector subsystem 5 receives the pulse number encoders, the detector collects the projection data of the X-ray tube, and records the angle information in the projection data. The detector subsystem 5 outputs the projection data in the original data to obtain reconstruction data.

[0085] Reconstruction module: The detector subsystem 5 transmits reconstruction data to the host computer 1 via the rotor control board 3. The reconstruction subsystem of the host computer 1 then reconstructs the medical image based on the reconstruction data.

[0086] It should be noted that this embodiment also provides a CT device, which is equipped with at least one of the systems provided in the above embodiment.

[0087] It should be noted that this embodiment also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method provided in the above embodiment.

[0088] It should be noted that the embodiments of the present invention have better implementability and are not intended to limit the present invention in any way. Any person skilled in the art may use the above-disclosed technical content to change or modify it into equivalent effective embodiments. However, any modifications or equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for reconstructing medical images after slip ring angle calibration, characterized in that, Including the following steps: Exposure commands are generated based on the CT equipment and sent to the stator control board via a host computer; The stator control board generates a rotation command based on the exposure command and sends the rotation command to the motor; The motor obtains the starting angle α according to the rotation command, and the motor feeds back the starting angle α to the stator control board; The stator control board calculates the number of pulse encoders required by the motor for this exposure based on the starting angle α and the exposure command, and sends the number of pulse encoders to the rotor control board and the motion control board respectively. The motion control board generates control commands based on the pulse number encoders and sends the control commands to the driver. The driver outputs a pulse signal equal to the number of encoders according to the control command. The slip ring is based on the pulse signal Will be with each of the pulse signals The corresponding angle information is sent to the detector subsystem; The rotor control board simultaneously sends the pulse number encoders to the detector subsystem. When the detector subsystem receives the pulse number encoders, the detector acquires the projection data of the X-ray tube, and the angle information is recorded in the projection data. The detector subsystem outputs the projection data in the original data to obtain the reconstructed data. The detector subsystem transmits the reconstructed data to the host computer via the rotor control board, and the host computer's reconstruction subsystem reconstructs the medical image based on the reconstructed data. When the motor obtains the starting angle α according to the rotation command, the motor is an ABZ incremental encoder, and the ABZ incremental encoder generates a Z-direction signal each time it passes the origin. When the angle at which each Z-axis signal is generated is defined as β, and the number of pulses (encoders) received by the motor from angle β to the initial angle α is f, the calculation formula is as follows: Obtain α, where α is the initial angle of the motor rotor for each revolution; β is the angle of the motor generating a Z-axis signal; allEncoders is the total number of encoders, which is equal to 4 × encodersMin, where encodersMin is the minimum number of encoders; and the % symbol is the remainder symbol. When the stator control board calculates the number of encoder pulses required by the motor for this exposure based on the starting angle α and the exposure command, it uses the following formula: Obtain the number of pulse encoders, where encodersMin is the minimum number of pulse encoders; The detector subsystem outputs the projection data into the original data and obtains the reconstructed data using the following calculation formula: Acquire reconstruction data, wherein The angle information when the detector acquires a certain projection data of the X-ray tube.

2. A system employing the method as described in claim 1, characterized in that, include: Exposure command generation module: used to generate exposure commands based on CT equipment and send the exposure commands to the stator control board through the host computer; Rotation command generation module: used by the customized control board to generate the rotation command based on the exposure command and send the rotation command to the motor; Acquisition module: used for the motor to acquire the starting angle α according to the rotation command, and the motor to feed back the starting angle α to the stator control board; The pulse count encoder module is used by the stator control board to calculate the number of pulse encoders required by the motor for this exposure based on the starting angle α and the exposure command. The stator control board then sends the calculated pulse count encoders to the rotor control board and the motion control board respectively. Control command generation module: used by the motion control board to generate the control command based on the pulse number encoders and send the control command to the driver; Output pulse signal Module: Used by the driver to output a pulse signal equal to the number of pulse signal encoders according to the control command. The slip ring is based on the pulse signal Will be with each of the pulse signals The corresponding angle information is sent to the detector subsystem; The module for acquiring reconstructed data is used by the rotor control board to simultaneously send the pulse number encoders to the detector subsystem. When the detector subsystem receives the pulse number encoders, the detector acquires the projection data of the X-ray tube, and the angle information is recorded in the projection data. The detector subsystem outputs the projection data in the original data to acquire reconstructed data. Reconstruction module: Used by the detector subsystem to transmit the reconstruction data to the host computer via the rotor control board, and the host computer's reconstruction subsystem reconstructs the medical image based on the reconstruction data.

3. A CT scanner, characterized in that, The CT device shall have at least one system as described in claim 2.

4. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it performs the steps as described in claim 1.

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