Multi-source cooperative imaging method and device on a circular accelerator and electronic equipment

Abstract

The application discloses a multi-light-source cooperative imaging method and device on a ring accelerator and electronic equipment, and relates to the technical field of medical treatment. The method comprises the following steps: acquiring the working state of a main treatment beam source and the rotation angle data of a ring accelerator frame; in the case that the main treatment beam source is in a standby state, controlling a telescopic mechanism to drive a plurality of imaging ray sources arranged on the inner wall surface of the ring accelerator frame to move from a first position to a second position; according to the rotation angle data, controlling at least one of the plurality of imaging ray sources to emit a beam; controlling a plurality of flat panel detectors to receive imaging rays passing through a target object, and acquiring projection data generated by the plurality of flat panel detectors, each flat panel detector being arranged opposite to at least one imaging ray source; and determining a three-dimensional image according to the projection data. The application solves the technical problem that it is difficult to integrate an image-guided system in a closed radiotherapy device such as a ring accelerator.

Description

Technical Field

[0001] This application relates to the field of medical technology, and more specifically, to a multi-source collaborative imaging method, apparatus, and electronic device on a ring accelerator. Background Technology

[0002] In radiotherapy, existing dual-source cone-beam computed tomography (CBCT) systems mostly employ C-arms or open ring gantry systems, where the imaging X-ray source and detector can be distributed in an open space, eliminating interference with the treatment head's movement. However, for enclosed equipment such as ring accelerators, the internal space of the enclosed ring gantry is compact, and the inner wall must accommodate moving components such as the treatment head and collimator. These components exhibit complex relative motion paths during gantry rotation. Due to the enclosed structure of the inner wall and the requirement for continuous rotation of the treatment head along the wall, existing dual-source cone-beam computed tomography systems are difficult to deploy in enclosed equipment such as ring accelerators.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This application provides a multi-source collaborative imaging method, apparatus, and electronic device on a ring accelerator, to at least solve the technical problem of the difficulty in integrating an image guidance system in closed radiotherapy equipment such as a ring accelerator.

[0005] According to one aspect of the embodiments of this application, a multi-source collaborative imaging method on a ring accelerator is provided, comprising: acquiring the working state of the main therapeutic beam source and the rotation angle data of the ring accelerator gantry; when the main therapeutic beam source is in a standby state, controlling a telescopic mechanism to drive multiple imaging beam sources disposed on the inner wall of the ring accelerator gantry to move from a first position to a second position, wherein, in the first position, the imaging beam source is located in the inner cavity of the ring accelerator gantry or flush with the inner wall; in the second position, the imaging beam source extends out of the inner wall; according to the rotation angle data, controlling at least one of the multiple imaging beam sources to trigger beam emission; controlling multiple flat panel detectors to receive imaging beams passing through a target object and acquiring projection data generated by the multiple flat panel detectors, wherein the multiple flat panel detectors are disposed on the ring accelerator gantry, and each flat panel detector is disposed opposite to at least one imaging beam source; and determining a three-dimensional image based on the projection data.

[0006] According to another aspect of the embodiments of this application, a multi-source collaborative imaging device on a ring accelerator is also provided, comprising: a first acquisition unit, configured to acquire the working state of the main therapeutic beam source and the rotation angle data of the ring accelerator gantry; a first processing unit, configured to, when the main therapeutic beam source is in standby mode, control a telescopic mechanism to drive multiple imaging beam sources disposed on the inner wall of the ring accelerator gantry to move from a first position to a second position, wherein, in the first position, the imaging beam source is located in the inner cavity of the ring accelerator gantry or flush with the inner wall; in the second position, the imaging beam source extends out of the inner wall; a second processing unit, configured to, based on the rotation angle data, control at least one of the multiple imaging beam sources to trigger beam emission; a third processing unit, configured to, control multiple flat panel detectors to receive imaging beams passing through the target object and acquire projection data generated by the multiple flat panel detectors, wherein the multiple flat panel detectors are disposed on the ring accelerator gantry, and each flat panel detector is disposed opposite to at least one imaging beam source; and a fourth processing unit, configured to, determine a three-dimensional image based on the projection data.

[0007] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, which stores a computer program, wherein when the computer program is executed, the device on which the computer-readable storage medium is located executes the above-described multi-source cooperative imaging method on a ring accelerator.

[0008] According to another aspect of the embodiments of this application, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to perform the above-described multi-source cooperative imaging method on a ring accelerator.

[0009] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program or instructions that, when executed by a processor, implement the above-described multi-source cooperative imaging method on a ring accelerator.

[0010] In this application, the imaging control system acquires the working status of the main treatment beam source and, when the main treatment beam source is in standby mode, controls a retractable mechanism to drive multiple imaging beam sources from a first position to a second position. This allows the multiple imaging beam sources to retract to be flush with the inner wall of the ring accelerator gantry or stored in the inner cavity during non-treatment periods, thereby freeing up movement space for the continuous rotation of the treatment head. This helps reduce physical interference between the imaging beam sources and the treatment head in the closed ring space. The imaging control system also controls at least one of the multiple imaging beam sources to trigger beam output based on the rotation angle data of the ring accelerator gantry, and controls multiple flat panel detectors to receive imaging beams to obtain projection data, thereby determining a three-dimensional image. This ensures that the imaging beam sources only extend and work within a preset angle window, which helps reduce the occupation of the treatment head's movement path. The imaging control system can achieve dynamic avoidance and collaborative operation of treatment and imaging functions in the closed ring space without increasing the axial length of the gantry, thus solving the technical problem of the difficulty in integrating an image guidance system in closed radiotherapy equipment such as ring accelerators. Attached Figure Description

[0011] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0012] Figure 1 This is a schematic diagram of an optional multi-source cooperative imaging method on a ring accelerator according to an embodiment of this application;

[0013] Figure 2 This is a structural diagram of an optional multi-source cooperative imaging device on a ring accelerator according to an embodiment of this application;

[0014] Figure 3 This is a schematic diagram of an optional multi-source cooperative imaging device on a ring accelerator according to an embodiment of this application.

[0015] In the picture:

[0016] 1. Circular accelerator frame;

[0017] 2. Imaging X-ray source;

[0018] 3. Flat panel detector; 31. Detector body; 32. Fine-tuning mechanism;

[0019] 4. Telescopic mechanism;

[0020] 5. Imaging control system; 51. Mode switching switch; 52. Hardware trigger circuit;

[0021] 61. Guide rail; 62. Slider;

[0022] 7. Target object. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] It should also be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, and displayed data) collected in this application are information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of related data all comply with the relevant laws, regulations, and standards of the relevant regions, necessary confidentiality measures have been taken, and they do not violate public order and good morals. Corresponding operation entry points are provided for users to choose to authorize or refuse. For example, this system has interfaces with relevant users or organizations. Before obtaining relevant information, a request to obtain the information needs to be sent to the aforementioned user or organization through the interface, and the relevant information is obtained only after receiving consent from the aforementioned user or organization.

[0026] According to an embodiment of this application, an embodiment of a multi-source cooperative imaging method on a ring accelerator is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0027] It should be noted that the information collected in this application (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for display, data used for analysis, etc.) are information and data authorized by the user or fully authorized by all parties. Furthermore, the collection, storage, use, processing, transmission, provision, disclosure, and application of this data all comply with relevant laws, regulations, and standards, necessary confidentiality measures have been taken, and they do not violate public order and good morals. Corresponding access points are provided for users to choose to authorize or refuse. For example, interfaces are set up between this system and relevant users or organizations, providing users with corresponding access points to choose to agree to or refuse automated decision-making results; if the user chooses to refuse, the process proceeds to the expert decision-making stage.

[0028] According to the embodiments of this application, an imaging control system can be used as the execution subject of the multi-source cooperative imaging method on the ring accelerator of this application embodiment. The system can be a software system or an embedded system combining software and hardware. Of course, the method execution subject in the embodiments of this application can also be other forms of execution subject, such as devices, equipment, etc. It should be known by those skilled in the art that this application does not particularly limit the specific form of the method execution subject.

[0029] Figure 1 This is a schematic diagram of a multi-source cooperative imaging method on a ring accelerator according to an embodiment of this application, as shown below. Figure 1 As shown, the method includes the following steps:

[0030] Step S101: Obtain the working status of the main therapeutic beam source and the rotation angle data of the annular accelerator gantry.

[0031] Optionally, the imaging control system can first acquire the operating status of the main therapeutic beam source. The main therapeutic beam source can be a linear accelerator mounted on a ring accelerator gantry, used to generate megavolt-level high-energy therapeutic rays. The linear accelerator generates a high-energy photon beam by accelerating electrons to collide with a metal target, or directly extracts an electron beam for the treatment of superficial tumors. Alternatively, the main therapeutic beam source can also be a radioactive isotope source, a proton accelerator, or a heavy ion accelerator. The operating status of the main therapeutic beam source can include at least the beam output state and the standby state. Acquiring the operating status of the main therapeutic beam source helps establish a safety interlock between treatment and imaging; that is, imaging operations are only permitted when it is confirmed that the therapeutic beam is not output, thereby avoiding damage to the flat panel detector caused by high-energy rays or the risk of accidental radiation to the user.

[0032] Optionally, the imaging control system can also simultaneously acquire the rotation angle data of the ring accelerator gantry. The ring accelerator gantry can have continuous rotation capability, and an angle encoder can be installed inside the gantry. By reading the signal from this angle encoder, the imaging control system can obtain the precise angle value of the gantry in real time. Acquiring rotation angle data is beneficial for achieving precise synchronization between the imaging beam output and the gantry rotation. In cone-beam computed tomography (CBCT) imaging, projection data acquisition needs to be performed at multiple different rotation angles. By acquiring rotation angle data in real time, the imaging control system can determine whether it is currently within a preset trigger angle window, thereby triggering beam output at the correct position, improving the uniformity and completeness of the spatial angular distribution of the acquired projection data, and contributing to improving the quality and accuracy of subsequent 3D image reconstruction.

[0033] For example, in a patient positioning and correction scenario, the imaging control system can read the interlock signal of the linear accelerator in real time via an internal bus. When the accelerator is not outputting high-energy rays, the interlock signal can be in a first-level state, representing a standby state. Simultaneously, the imaging control system can read the angle encoder values ​​mounted on the ring gantry drive shaft at a preset frequency of 1000 times per second to obtain the rotation angle data of the ring accelerator gantry. The imaging control system can store the operating status of the main treatment beam source (i.e., the standby state represented by the interlock signal) and the rotation angle data of the ring accelerator gantry (i.e., the angle encoder values) in its memory for subsequent imaging triggering decisions.

[0034] For example, in a respiratory-gated imaging scenario, the imaging control system can establish a connection with the main therapeutic beam source controller via a communication interface, periodically receiving status messages from the main therapeutic beam source in data frame format, and parsing out the beam emission permission or prohibition status flags from the status messages. Simultaneously, the imaging control system can wirelessly receive angle data packets from the gantry angle sensor, and after parsing the angle data packets, obtain the current rotation angle of the circular accelerator gantry, for example, within a scanning arc of 90 to 270 degrees. Based on the status flags of the main therapeutic beam source and the current rotation angle of the circular accelerator gantry, the imaging control system determines whether to trigger multiple imaging beam sources and the timing of triggering multiple imaging beam sources.

[0035] In step S102, when the main treatment beam source is in standby mode, the retractable mechanism is controlled to drive multiple imaging beam sources disposed on the inner wall of the annular accelerator gantry to move from a first position to a second position. In the first position, the imaging beam source is located in the inner cavity of the annular accelerator gantry or flush with the inner wall; in the second position, the imaging beam source extends out of the inner wall.

[0036] Optionally, the imaging control system only executes the action of controlling the retractable mechanism after confirming that the main therapeutic beam source is in standby mode. The main therapeutic beam source being in standby mode indicates that there is no high-energy therapeutic radiation output at this time, allowing the imaging beam source to move into the working position. By establishing a safety interlock condition, it is beneficial to avoid the accidental extension of multiple imaging beam sources during the beam output process of the main therapeutic beam source, thereby preventing potential damage to the flat panel detector from high-energy radiation and additional radiation risks to the user.

[0037] Optionally, the imaging control system controls a retractable mechanism to move multiple imaging X-ray sources mounted on the inner wall of the annular accelerator gantry from a first position to a second position. The retractable mechanism may include a motor-driven lead screw mechanism or a cylinder-driven linkage mechanism, with each imaging X-ray source mounted inside the annular accelerator gantry via the retractable mechanism. In the first position, the multiple imaging X-ray sources can be completely retracted into the annular accelerator gantry cavity, or their outermost edges can be flush with the inner wall of the annular accelerator gantry. When the multiple imaging X-ray sources are in the first position, space can be provided for the movement of the treatment head during non-imaging periods, preventing physical interference between the treatment head and the imaging X-ray sources. When imaging scanning is required, the imaging control system can issue a drive command to the retractable mechanism, which will extend the imaging X-ray sources from the first position, causing them to extend towards the gantry's rotation center and reach the predetermined second position. In the second position, the imaging beam source extends beyond the inner wall and enters a suitable position for emitting imaging beams. This facilitates the integration of multiple imaging sources in a space-constrained annular enclosed device and allows for dynamic avoidance of the treatment head's movement path, enabling the treatment and imaging functions to work collaboratively on the same rotating frame.

[0038] For example, the multiple radiation sources may include a first X-ray source and a second X-ray source. Both the first and second X-ray sources can be enclosed X-ray tubes, installed at relative positions inside the ring accelerator gantry. When image-guided verification is required after completing a radiotherapy session, the imaging control system detects that the main treatment beam source is in standby mode. The imaging control system sends an extension command to a motor-driven lead screw mechanism installed inside the ring accelerator gantry. The motor-driven lead screw rotates, causing a slider fixedly connected to the first and second X-ray sources to move outward along a guide rail, extending the first and second X-ray sources from a first position flush with the inner wall of the ring accelerator gantry a predetermined distance to a second position. The predetermined distance may be, but is not limited to, 150 mm. At this time, the emission windows of the first and second X-ray sources are aligned with the rotation center of the ring accelerator gantry, ready for projection data acquisition.

[0039] For example, respiratory gating imaging can refer to imaging technology synchronized with the patient's respiratory cycle. It uses respiratory gating monitoring devices such as breathing belts, infrared tracking systems, or cameras to monitor the patient's respiratory phase in real time. The X-ray source is triggered to capture projection data only during specific phases of the respiratory cycle, such as the plateau phase at the end of expiration. This reduces image blurring or motion artifacts caused by respiratory motion, resulting in a clear image of the tumor location. When respiratory gating imaging is required during treatment, the imaging control system, upon receiving a gating signal from the respiratory gating monitoring device, first confirms that the main treatment beam source is in standby mode. The system then supplies air to the cylinder via a pneumatic control valve, driving the telescopic arm connected to the imaging X-ray source assembly. The telescopic arm extends multiple imaging X-ray sources from a first position housed within the gantry along a linear guide rail until the front end of the imaging X-ray source reaches a preset second position. After a limit switch on the telescopic path is triggered, the imaging control system confirms that the imaging X-ray source has extended to its designated position, then stops driving and locks the telescopic mechanism, maintaining the stability of the imaging X-ray source in its working position.

[0040] Step S103: Based on the rotation angle data, control at least one of the multiple imaging X-ray sources to trigger beam output.

[0041] Optionally, the imaging control system determines whether the current position of the ring accelerator gantry meets the imaging triggering conditions based on the acquired rotation angle data. The rotation angle data characterizes the instantaneous angle value of the gantry during a continuous 360-degree rotation. The imaging control system can pre-store one or more trigger angle windows, each corresponding to an angle interval. When the ring accelerator gantry rotates into the angle interval corresponding to the trigger angle window, the imaging control system determines that the triggering conditions are met; when the ring accelerator gantry rotates outside the angle interval, the imaging control system determines that the triggering conditions are not met. This angle window-based judgment mechanism helps ensure that the imaging beam exits only within a preset angle range that is conducive to projection data acquisition in a spatially advantageous location, thereby optimizing the sampling strategy and reducing unnecessary radiation exposure.

[0042] Optionally, when the imaging control system determines that the triggering conditions are met, it controls at least one of the multiple imaging X-ray sources to trigger beam emission. Beam emission triggering may include the imaging control system sending a trigger pulse signal to the high-voltage generator of the imaging X-ray source, causing the imaging X-ray source to begin emitting imaging rays, such as cone-beam X-rays, at a specified time point. The imaging control system can select to activate one or more imaging X-ray sources according to different imaging requirements, and can configure the triggering timing relationship between two imaging X-ray sources. For example, the imaging control system can control two imaging X-ray sources to emit beams alternately to achieve high temporal resolution imaging, or it can control two imaging X-ray sources to emit beams at different angle intervals to achieve artifact suppression, or it can control two imaging sources to emit beams simultaneously to achieve dual-energy imaging or large field-of-view coverage. By precisely controlling the beam emission timing and method based on rotation angle data, the imaging control system helps improve the sampling uniformity of the projection data in spatial angles, which is beneficial for subsequent high-quality 3D image reconstruction.

[0043] For example, the imaging control system can pre-set the trigger angle window to a first angle range, such as a continuous range from the starting angle to the ending angle. When the annular accelerator gantry begins to rotate at a constant speed from the starting angle, the imaging control system reads the angle encoder value in real time. Whenever the rotation angle of the annular accelerator gantry falls within the preset trigger angle window, the imaging control system sends a trigger pulse to the first imaging ray source, causing the first imaging ray source to emit beams according to a preset timing sequence. When the rotation angle of the annular accelerator gantry exceeds the trigger angle window, the imaging control system stops triggering beam emission, completing the acquisition of projection data within that angle range.

[0044] For example, the imaging control system sets two discontinuous trigger angle windows, including a first trigger angle window and a second trigger angle window. The first trigger angle window corresponds to a first imaging X-ray source, and the second trigger angle window corresponds to a second imaging X-ray source. When the annular accelerator gantry rotates to the angle range corresponding to the first trigger angle window, the imaging control system triggers the first imaging X-ray source to emit a beam; when the annular accelerator gantry rotates to the angle range corresponding to the second trigger angle window, the imaging control system triggers the second imaging X-ray source to emit a beam. The first and second imaging X-ray sources emit beams in different angle ranges, and the projection data acquired from these different angle ranges can be used for subsequent image correction and fusion.

[0045] Step S104: Control multiple flat panel detectors to receive imaging rays passing through the target object and acquire projection data generated by the multiple flat panel detectors. The multiple flat panel detectors are set on the ring accelerator gantry, and each flat panel detector is set opposite to at least one imaging ray source.

[0046] Optionally, the imaging control system controls multiple flat panel detectors to receive imaging rays passing through a target object, such as a patient lying on a treatment bed. The flat panel detectors can be, but are not limited to, amorphous silicon-based flat panel detectors, with an effective imaging area of ​​not less than 40 cm x 30 cm. The flat panel detectors are fixedly mounted on the inner wall of the annular accelerator gantry, arranged opposite the imaging ray source. When the imaging ray source triggers beam emission, the imaging ray is emitted from the imaging ray source, passes through the target object located near the rotation center of the gantry, and attenuates as it penetrates the target object. The attenuated ray reaches the flat panel detector on the opposite side. The flat panel detector converts the received ray signal into an electrical signal, completing the initial conversion process from ray to image. Each flat panel detector is positioned opposite at least one imaging ray source to ensure that when an imaging ray source emits a beam, at least one flat panel detector is in an effective position to receive that beam. For example, when a first imaging ray source and a first flat panel detector are symmetrically arranged on the annular accelerator gantry, after the first imaging ray source emits a beam, the conical beam emitted by the first imaging ray source passes through the target object and is projected onto the opposite first flat panel detector.

[0047] Optionally, the imaging control system can acquire projection data generated by multiple flat panel detectors. Projection data is digital image data generated by the flat panel detectors after analog-to-digital conversion of the received X-ray signals. During cone-beam computed tomography (CBCT) imaging, as the ring accelerator gantry rotates continuously, the flat panel detectors acquire multiple two-dimensional projection images at different angles. The imaging control system can read the projection data in real time via high-speed Ethernet or data cables and store the projection data in a memory for subsequent 3D image reconstruction. By coordinating multiple flat panel detectors with multiple imaging X-ray sources, projection data from different viewing angles can be acquired during a single gantry rotation, which improves data acquisition efficiency and enriches the image information available for reconstruction.

[0048] For example, during cone-beam computed tomography (CBCT) imaging, the imaging control system initiates a data acquisition task for a first flat-panel detector positioned opposite the first imaging X-ray source simultaneously with triggering the beam output from the first imaging X-ray source. The imaging X-ray passes through the target object and reaches the first flat-panel detector, which continuously acquires images at a preset frame rate. The imaging control system reads each frame of projection data via a data cable and associates and stores each frame of projection data with the corresponding rotation angle data of the annular accelerator gantry for subsequent 3D image reconstruction.

[0049] For example, in the alternating beam emission mode, the imaging control system controls the first and second imaging X-ray sources to emit beams in an alternating sequence. When the first imaging X-ray source emits its beam, the imaging control system controls the first flat panel detector, which is positioned opposite the first imaging X-ray source, to perform exposure and data readout. In subsequent alternating cycles, when the second imaging X-ray source emits its beam, the imaging control system controls the second flat panel detector, which is positioned opposite the second imaging X-ray source, to perform exposure and data readout. The first projection data generated by the first flat panel detector and the second projection data generated by the second flat panel detector are stored in different data buffers. The imaging control system marks them according to their respective corresponding annular accelerator gantry rotation angle labels to distinguish projection data from different viewpoints during image reconstruction.

[0050] Step S105: Determine the three-dimensional image based on the projection data.

[0051] Optionally, the imaging control system can determine a three-dimensional image based on the acquired projection data. The projection data is a sequence of two-dimensional projection images acquired by a flat-panel detector at different angles during the rotation of the circular accelerator gantry. Each frame of the two-dimensional projection image records the intensity distribution information of the imaging rays as they pass through the target object on the detector plane; this intensity distribution is related to the density and composition of the internal tissue of the target object along the ray path. The imaging control system uses the projection data with angle labels as input and passes it to the image reconstruction module for processing.

[0052] Optionally, the determination of the 3D image can employ 3D reconstruction techniques, such as filtered backprojection algorithms or iterative reconstruction algorithms. The filtered backprojection algorithm first filters each frame of 2D projection data to compensate for image blur. Then, it projects the filtered projection data back onto a voxel grid in 3D space according to the corresponding geometric projection relationship. By accumulating the projection data from all angles, the attenuation coefficient corresponding to each voxel is calculated, thus forming 3D volume data. The iterative reconstruction algorithm starts from the initially estimated 3D volume data, calculates the estimated projection through forward projection, compares the estimated projection with the actually acquired projection data, and repeatedly updates the 3D volume data based on the difference between the estimated and actual projection data until a preset convergence condition is met. The reconstructed 3D image can be used for patient positioning correction, target localization, and real-time tracking guidance during treatment. This 3D image is coaxial with the treatment center of the circular accelerator, allowing direct correspondence between the image coordinate system and the treatment coordinate system without additional registration, which helps improve the efficiency and accuracy of image-guided radiotherapy.

[0053] For example, the imaging control system can input the acquired multi-frame two-dimensional projection data into the filtering backprojection reconstruction module. The filtering backprojection reconstruction module first transforms and filters each frame of projection data, and then projects the filtered data back onto a three-dimensional voxel mesh according to geometric parameters, ultimately generating a three-dimensional image of the target object.

[0054] For example, the imaging control system can acquire a first projection data sequence generated by a first flat panel detector and a second projection data sequence generated by a second flat panel detector. The imaging control system can fuse the first projection data sequence and the second projection data sequence according to their respective projection angles to form a fused projection dataset. The imaging control system uses an iterative reconstruction algorithm to process the fused projection dataset, and after a preset number of iterations, a three-dimensional image is obtained. Metal artifacts in this three-dimensional image can be effectively suppressed, and image contrast and spatial resolution can be effectively improved.

[0055] It should be noted that, compared to axially offsetting the X-ray source and treatment head, which leads to increased axial length of the gantry, disrupted imaging geometry, and inability to achieve coplanarity, this application mounts multiple imaging X-ray sources onto the inner wall of the annular accelerator gantry via a retractable mechanism. During non-imaging periods, the imaging X-ray sources retract to be flush with the inner wall or stored within the cavity, providing ample space for continuous rotation of the treatment head. This avoids the reduced patient accessibility and difficulty in counterweighting caused by increased axial length. During imaging periods, the imaging X-ray sources extend to their working position and point to the same isocenter point, sharing the rotation axis with the treatment head and maintaining coplanarity between the treatment beam and the imaging beam, which improves the geometric accuracy of 3D reconstruction. Simultaneously, by monitoring the operating status of the main treatment beam generating device and establishing a safety interlock, the imaging X-ray sources are only allowed to extend and exit when the treatment beam is in standby mode, reducing the risk of damage to the flat panel detector from high-energy rays. While ensuring the coaxial accuracy of treatment and imaging, the embodiments of this application are conducive to realizing dynamic avoidance and safe coordination of treatment and imaging functions within a limited annular space, reducing spatial interference and geometric mismatch problems caused by axial offset settings.

[0056] For ease of understanding, Figure 2A schematic diagram of a multi-source collaborative imaging device on a ring accelerator is shown. The ring accelerator gantry 1 is a ring-shaped structure with a central opening for accommodating the target object 7, and it also carries the main therapeutic beam source. A guide rail 61 is circumferentially arranged on the inner wall of the ring accelerator gantry 1, and the guide rail 61 is slidably engaged with a slider 62, which can slide along the extension direction of the guide rail 61. One end of a telescopic mechanism 4 is fixedly connected to the slider 62, and the other end is fixedly connected to the imaging beam source 2, thereby mounting the imaging beam source 2 on the slider 62 via the telescopic mechanism 4. The telescopic mechanism 4 drives the imaging beam source 2 to move between a first position and a second position relative to the inner wall of the ring accelerator gantry 1. The imaging beam source 2 is arranged circumferentially along the ring accelerator gantry 1 and is used to emit imaging beams during imaging. Figure 2 The example uses two imaging X-ray sources, specifically the first and second imaging X-ray sources. Multiple flat panel detectors 3 are mounted on the annular accelerator gantry 1, each positioned opposite at least one imaging X-ray source 2 to receive imaging X-rays. Each flat panel detector 3 includes a detector body 31 and a fine-tuning mechanism 32, positioned between the detector body 31 and the annular accelerator gantry 1, for adjusting the distance and tilt angle between the detector body 31 and the oppositely positioned imaging X-ray source 2. An imaging control system 5 is communicatively connected to the multiple imaging X-ray sources 2, used to adjust the triggering of the beams from the multiple imaging X-ray sources 2 during the rotation of the annular accelerator gantry 1, and to monitor the beam output status of the main therapeutic beam. The imaging control system 5 includes a mode switching switch 51 and a hardware trigger circuit 52. The mode switching switch 51 is connected to the hardware trigger circuit 52, which has multiple output terminals connected to the multiple imaging X-ray sources 2 respectively. Each position of the mode switching switch 51 is coupled to a different output terminal of the hardware trigger circuit 52, used to output trigger signals with different timing characteristics to the imaging X-ray sources 2. The target object 7 is located inside the central opening of the annular accelerator gantry 1 and is irradiated by imaging rays.

[0057] In some optional embodiments, controlling at least one of the multiple imaging X-ray sources to trigger beam emission based on rotation angle data includes: the imaging control system can determine the current angle range of the annular accelerator gantry based on the rotation angle data; when the angle range belongs to a preset trigger angle window, controlling at least one of the multiple imaging X-ray sources to trigger beam emission according to a preset timing sequence, wherein the preset timing sequence indicates that the trigger time and beam emission duration of each imaging X-ray source are configured according to a preset time relationship; when the angle range does not belong to the trigger angle window, controlling the multiple imaging X-ray sources to stop beam emission.

[0058] Optionally, the rotation angle data can refer to a specific angle value. The imaging control system can compare this angle value with multiple preset angle ranges, such as 0 degrees to 90 degrees, 90 degrees to 180 degrees, etc., to determine which angle range the current angle value falls into. Compared with single-point judgment, the range judgment method can increase the system's tolerance to angle signal jitter and reduce false triggering or missed triggering caused by instantaneous fluctuations in the angle encoder signal.

[0059] Optionally, the imaging control system determines whether the current angle interval belongs to a preset trigger angle window. When the angle interval belongs to the trigger angle window, the imaging control system controls at least one of the multiple imaging X-ray sources to trigger beam emission according to a preset timing sequence. The preset timing sequence indicates that the trigger time and beam emission duration of each imaging X-ray source are configured according to a preset time relationship. For example, during the beam emission duration of the first imaging X-ray source, the second imaging X-ray source is in standby mode; after the first imaging X-ray source stops emitting beam, the second imaging X-ray source starts emitting beam after a preset time interval. The configuration of the preset timing sequence is implemented through a hardware trigger signal. When the angle interval does not belong to the trigger angle window, the imaging control system controls the multiple imaging X-ray sources to stop emitting beam. If no imaging X-ray source has emitted beam before, the multiple imaging X-ray sources remain in standby mode; if an imaging source is in the process of emitting beam, the imaging control system immediately sends a stop command to interrupt the beam emission action. The beam control logic based on angle interval determination and preset timing helps ensure that multiple imaging X-ray sources emit beams only within a predetermined geometric angle range and in a specific timing sequence. This enables various imaging strategies, such as alternating beam emission to improve temporal resolution and time-division beam emission to suppress artifacts, while avoiding invalid or redundant exposures within undesired angle windows.

[0060] For example, in a dynamic tumor tracking scenario, the imaging control system can set the trigger angle window to the entire 360-degree range, meaning that a beam is triggered every 1 degree of rotation of the circular accelerator gantry. The system can employ a preset timing sequence in a dual-source synchronous alternating mode, controlling the first and second imaging X-ray sources to alternately emit beams every 2 milliseconds. When the gantry rotation angle data falls within the current trigger window, the system continuously executes the alternating beam emission sequence, acquiring 360 sets of dual-view alternating projection data during one rotation of the gantry, which are then used for subsequent high temporal resolution image reconstruction.

[0061] For example, in a metal artifact suppression scenario, the imaging control system can set two discontinuous trigger angle windows, including a first trigger angle window and a second trigger angle window. When the rotation angle of the annular accelerator gantry falls within the first trigger angle window, for example, 0 degrees to 90 degrees, the imaging control system controls only the first imaging X-ray source to continuously emit beams; when the rotation angle of the annular accelerator gantry falls within the second trigger angle window, for example, 180 degrees to 270 degrees, the imaging control system controls only the second imaging X-ray source to continuously emit beams; when the rotation angle of the annular accelerator gantry falls within an angle range that does not belong to either trigger angle window, the imaging control system controls all imaging X-ray sources to stop emitting beams. The acquired projection data comes from two complementary angle ranges and is used for subsequent artifact suppression through fusion processing.

[0062] In some optional embodiments, controlling at least one of a plurality of imaging X-ray sources to trigger beam emission according to a preset timing sequence includes: the imaging control system can determine a target operating mode from a plurality of operating modes, wherein the plurality of operating modes include at least two of a single-source operating mode, a multi-source synchronous alternating mode, a multi-source time-division coordinating mode, and a multi-source joint overlapping mode; and controlling the plurality of imaging X-ray sources to trigger beam emission according to the target operating mode.

[0063] Optionally, the imaging control system selects one of several operating modes as the target operating mode. These modes may include at least two of the following: single-source operating mode, multi-source synchronous alternating mode, multi-source time-sharing coordinated mode, and multi-source combined overlap mode. Single-source operating mode refers to using only one imaging source from multiple imaging sources for beam emission imaging, suitable for setup verification or low-dose screening scenarios. Multi-source synchronous alternating mode refers to two or more imaging sources emitting beams alternately according to a preset alternation cycle, with only one imaging source emitting beams at any given time, which helps improve temporal resolution. Multi-source time-sharing coordinated mode can refer to different imaging sources triggering beam emission at different angular intervals within the rotating gantry of the circular accelerator, with preset intervals or non-overlapping intervals between these intervals, which helps suppress artifacts through complementary information. Multi-source combined overlap mode refers to two or more imaging sources triggering beam emission simultaneously, or different imaging sources having overlapping areas within the angular intervals covered by the gantry rotation, which helps expand the imaging field of view or enhance data density in specific angular intervals. By providing multiple selectable operating modes, the imaging control system can flexibly configure imaging strategies according to clinical needs.

[0064] Optionally, the imaging control system controls multiple imaging X-ray sources to trigger beam emission according to a defined target operating mode. When the target operating mode is a single-source operating mode, the imaging control system sends a trigger signal only to the first imaging X-ray source, while the second imaging X-ray source remains in standby mode. When the target operating mode is a multi-source synchronous alternating mode, the imaging control system alternately sends trigger signals to the first and second imaging X-ray sources according to a preset alternation cycle, so that the first and second imaging X-ray sources emit beams in a time-sharing manner. When the target operating mode is a multi-source time-sharing cooperative mode, the imaging control system triggers the first imaging X-ray source to emit beams when the annular accelerator gantry is in a first angular range, and triggers the second imaging source to emit beams when the annular accelerator gantry is in a second angular range. When the target operating mode is a multi-source joint overlapping mode, the imaging control system simultaneously sends trigger signals to the first and second imaging X-ray sources, or configures the angular coverage ranges of the first and second imaging sources to overlap. This flexible control mechanism based on operating modes helps the same hardware platform adapt to different imaging requirements, achieving a balance between imaging quality, temporal resolution, and radiation dose.

[0065] For example, the imaging control system may receive a mode selection command and determine the single-source operating mode as the target operating mode. The imaging control system only activates the first imaging X-ray source. During the rotation of the annular accelerator gantry, the imaging control system only sends a trigger signal to the first imaging X-ray source, while the second imaging X-ray source remains in standby mode.

[0066] For example, the imaging control system receives a respiratory gating signal in real time. When the respiratory gating signal indicates that the target object is in a stable phase of its respiratory cycle, the imaging control system switches the target operating mode to a multi-source synchronous alternating mode. During the rotation of the annular accelerator gantry, the imaging control system controls the first and second imaging X-ray sources to alternately emit beams according to a preset alternation cycle. When the respiratory gating signal indicates that the target object is in a motion phase, the imaging control system pauses beam emission.

[0067] In some optional embodiments, determining the target operating mode from multiple operating modes includes: the imaging control system acquiring the position signal of a mode switching switch, wherein the mode switching switch has at least two positions, each of the at least two positions corresponding to a different imaging X-ray source operating mode; and determining the target operating mode based on the position signal.

[0068] Optionally, the mode switch can be a physical knob or toggle switch located on the control panel, or a virtual switch presented in a graphical user interface. The mode switch has at least two positions, each corresponding to a different imaging X-ray source operating mode. For example, the first position can correspond to a single-source operating mode, the second to a multi-source synchronous alternating mode, the third to a multi-source time-sharing coordinated mode, and the fourth to a multi-source joint overlapping mode. When the user rotates the knob or toggle switch to one of the at least two positions, the mode switch generates an electrical or digital signal corresponding to that position, and the imaging control system reads the signal corresponding to that position through an input interface. This hardware-based mode selection method provides intuitive operational feedback, allowing operators to quickly switch imaging modes without navigating through multi-level software menus.

[0069] Optionally, the imaging control system can store a mapping table that records the correspondence between gear position signals and operating modes. For example, when a low-level gear position signal is detected, indicating the first gear position, the system determines the target operating mode as a single-source operating mode; when an coded pulse-width modulation signal is detected, indicating the second gear position, the system determines the target operating mode as a multi-source synchronous alternating mode. By analyzing the gear position signals, the system can determine the imaging strategy that the operator intends to use. Determining the target operating mode based on gear position signals simplifies the operation process, reduces the risk of misoperation due to complex software interfaces, and is suitable for clinical environments requiring rapid response.

[0070] For example, four virtual buttons can be set on the touch screen control interface, each corresponding to a working mode, and linked to the electronic setting of a mode switch. When the operator clicks the respiratory gating mode button, the electronic switch internally switches to the setting corresponding to the multi-source synchronous alternating mode. After receiving the setting signal, the imaging control system automatically configures the target working mode to the multi-source synchronous alternating mode and adjusts the alternation period parameter to adapt to the time resolution requirements of respiratory gating imaging.

[0071] In an optional embodiment, a target operating mode is determined from multiple operating modes, including: the imaging control system can acquire respiratory gating signals or tumor tracking instructions; and the target operating mode is dynamically selected based on the respiratory gating signals or tumor tracking instructions.

[0072] Optionally, respiratory gating signals can originate from external respiratory monitoring devices such as breathing belts, infrared tracking systems, or cameras, used to characterize the respiratory phase of the target subject in real time. Tumor tracking commands can originate from a host computer or the doctor's console, instructing the system to enter dynamic tracking mode to follow the moving tumor target area. During radiotherapy, the respiratory movements or spontaneous organ movements of the target subject can cause periodic or non-periodic shifts in the tumor location; therefore, respiratory gating signals or tumor tracking commands can be acquired. If a fixed imaging mode is used to acquire projection data, motion artifacts may appear in the acquired images, leading to blurred tumor boundaries or positional deviations, thus affecting the accuracy of subsequent image guidance and treatment efficacy.

[0073] Optionally, the imaging control system can dynamically select the target operating mode based on the acquired respiratory gating signal or tumor tracking command. This dynamic selection of the target operating mode is not fixed but can be adjusted in real-time based on received physiological signals or external commands. For example, when a respiratory gating signal indicates that the target object is at a specific stage of the respiratory cycle, such as end-expiration, the imaging control system can select a multi-source synchronous alternating mode to rapidly acquire multi-view projection data within a short time window, freezing organ displacement caused by respiratory motion. When a tumor tracking command is received, the imaging control system can select a multi-source combined overlapping mode, increasing data density at specific angles through simultaneous beam output to more accurately capture the location of rapidly moving tumors. By dynamically switching operating modes based on respiratory gating signals or tumor tracking commands, the imaging control system can employ adaptive imaging strategies in different clinical scenarios, helping to reduce motion artifacts in imaging moving organs and improving the real-time performance and accuracy of image guidance.

[0074] For example, during radiotherapy for lung tumors, the imaging control system receives respiratory gating signals from the respiratory monitoring device in real time. When the respiratory gating signal indicates that the patient is in a stable plateau phase at the end of expiration, the imaging control system automatically switches the target operating mode to a multi-source synchronous alternating mode, causing the first and second imaging X-ray sources to fire rapidly at a frequency of alternating every 5 milliseconds, completing dual-view projection data acquisition within the stable respiratory window. When the respiratory gating signal indicates that the patient is in the inspiratory phase, the imaging control system pauses firing the X-rays, waiting for the next end-expiratory window before resuming acquisition.

[0075] For example, in stereotactic radiotherapy for liver cancer, the physician can send tumor tracking commands to the imaging control system via the control panel. Upon receiving the tumor tracking command, the imaging control system dynamically switches the target operating mode from single-source mode to multi-source combined overlapping mode, controlling the first and second imaging X-ray sources to emit beams simultaneously, and configuring overlapping areas within the gantry rotation angle range. For example, the first X-ray source covers 0 to 120 degrees, and the second source covers 60 to 180 degrees. By combining overlapping beams, the imaging control system obtains double the projection data density within the overlapping angle range, which helps to more accurately locate the position of mobile liver tumors affected by respiration.

[0076] In an optional embodiment, controlling multiple imaging X-ray sources to trigger beam emission according to a target operating mode includes: when the target operating mode is a multi-source synchronous alternating mode, the imaging control system can control at least two of the multiple imaging X-ray sources to alternately emit beams according to a preset alternation period, wherein the alternation period characterizes the time required for each imaging X-ray source to complete one beam emission cycle in sequence, and during the alternating beam emission process, only one imaging X-ray source is in the beam emission state at any given time.

[0077] Optionally, multi-source synchronous alternating mode can refer to two or more imaging sources firing in turn according to a fixed time sequence, with only one imaging source firing at any given time. For example, during radiotherapy for chest or abdominal tumors, the patient's respiratory movements or heartbeats can cause periodic displacement of the tumor position, thus requiring multi-source synchronous alternating mode. If a single-source imaging method is used, a large gantry rotation range is required to acquire sufficient projection data, and this acquisition process spans multiple respiratory cycles. The reconstructed image will contain varying degrees of motion artifacts, resulting in blurred tumor boundaries. By using multi-source synchronous alternating mode, multiple imaging sources fire alternately within a short time window of milliseconds, allowing for near-simultaneous acquisition of projection data from multiple different visual directions. This effectively doubles the temporal resolution, helping to freeze organ motion and complete data acquisition within a stable window of a single respiratory cycle.

[0078] Optionally, the alternation period characterizes the time required for each imaging X-ray source to complete one beam-out cycle sequentially. For example, when two imaging X-ray sources are used for alternating beam outflow, the alternation period may include the beam-out duration of the first imaging X-ray source, a first switching gap between the cessation of beam outflow from the first imaging X-ray source and the commencement of beam outflow from the second imaging X-ray source, the beam-out duration of the second imaging X-ray source, and a second switching gap between the cessation of beam outflow from the second imaging X-ray source and the commencement of beam outflow from the first imaging X-ray source. The value of the alternation period can be configured according to clinical needs; for example, a shorter alternation period can be used to improve temporal resolution when imaging rapidly moving organs, while a longer alternation period can be used to reduce the system hardware load in slower-moving areas. During alternating beam outflow, only one imaging X-ray source is in the beam-out state at any given time, which avoids projection data aliasing caused by simultaneous beam outflow from two sources and unnecessary increase in radiation dose to the target object. The imaging control system can precisely control the alternation period and switching timing through hardware trigger signals such as timing pulses output by the programmable logic controller. The delay time can be controlled at the sub-millisecond level, which helps to ensure the temporal proximity of the projection data from the two viewpoints, thereby reducing the impact of motion artifacts on image quality.

[0079] For example, in respiratory gated imaging of lung tumors, the imaging control system configures the alternation period to 5 milliseconds, where the first imaging source emits beams for 2 milliseconds with a 0.5 millisecond switching interval after beam emission stops, and the second imaging source emits beams for 2 milliseconds with a 0.5 millisecond switching interval after beam emission stops. When the respiratory monitoring device sends an end-expiratory gating signal, the imaging control system initiates the alternating beam emission sequence. The first and second imaging sources each emit beams once within the 5-millisecond alternation period, continuously executing multiple alternation periods within the stable respiratory window to acquire sufficient dual-view projection data.

[0080] For example, the imaging control system can be linked with a physiological signal monitoring device. When the physiological signal monitoring device detects a relatively stable phase window in the physiological cycle, the imaging control system configures the alternation cycle to a preset duration. Within this stable time window, the imaging control system can continuously execute multiple alternation cycles, acquiring multiple sets of dual-view projection data for reconstructing dynamic three-dimensional images with high temporal resolution.

[0081] In one optional embodiment, controlling multiple imaging X-ray sources to trigger beam emission according to a target operating mode includes: when the target operating mode is a multi-source time-division coordinating mode, controlling at least two of the multiple imaging X-ray sources to trigger beam emission in different angle intervals of the rotation of the annular accelerator gantry, wherein the angle intervals have a preset interval angle or do not overlap.

[0082] Optionally, the multi-source time-sharing collaborative mode can refer to different imaging X-ray sources operating at different angular segments of the rotating ring accelerator gantry, each responsible for acquiring projection data within a specific angular range. In certain imaging scenarios, multi-source time-sharing collaborative mode can be executed from complementary, non-continuous angular intervals, and acquiring projection data helps improve image quality. For example, when there are metal implants such as dental fillings, orthopedic internal fixation devices, or surgical clips in the target object, the metal objects will attenuate and scatter the imaging X-rays, resulting in strip-shaped or radial artifacts in the projection data in certain angular directions. These artifacts will contaminate the reconstructed image, obscure the true anatomical structure, and reduce the quality of the reconstructed image. If a single-source or full-angle scanning method is used, metal artifacts are difficult to remove effectively. By adopting the multi-source time-sharing collaborative mode, multiple imaging X-ray sources acquire projection data in multiple non-overlapping angular intervals, such as 0 degrees to 90 degrees and 180 degrees to 270 degrees, with each angular interval geometrically complementary and non-overlapping. Each angular interval can have a preset interval angle, meaning the interval angle is greater than zero, or the angular intervals do not overlap. This can mean that the ending angle of one angular interval equals the starting angle of another, and the two intervals are adjacent at the boundary but have no common angle value. For example, the first interval is 0 degrees to 90 degrees, and the second interval is 90 degrees to 180 degrees, with an interval angle that can be zero. The acquired multiple sets of projection data each contain different artifact distribution characteristics. The imaging control system can subsequently fuse these multiple sets of data using algorithms such as projection domain-based correction or dual-energy subtraction techniques, utilizing complementary information to suppress or eliminate metal artifacts.

[0083] Optionally, setting preset interval angles or non-overlapping angles between different angle ranges can prevent two imaging X-ray sources from being repeatedly exposed near the same angle, helping to reduce unnecessary radiation dose. The size of the interval angle can be configured according to the requirements of artifact suppression. The larger the interval angle, the stronger the spatial complementarity of multiple sets of projection data and the better the artifact correction effect; the smaller the interval angle, the more continuous the angle sampling. The imaging control system can automatically select appropriate interval angle parameters according to the type, size, and location of the metal implant inside the target object. By constraining the acquisition of projection data to multiple complementary, non-overlapping angle ranges, the multi-source time-division collaborative mode helps to acquire diverse projection information while maintaining sufficient sampling angles, which is beneficial for subsequent image fusion and artifact correction.

[0084] For example, in the radiotherapy localization after a patient's hip arthroplasty with a metal prosthesis, the imaging control system configures the target operating mode to a multi-source time-sharing collaborative mode. The beam angle range of the first imaging source is set to 0 to 80 degrees, and the beam angle range of the second imaging source is set to 100 to 180 degrees, with a 20-degree interval between the two ranges. When the circular accelerator gantry rotates, the first imaging source emits beams in the 0-80 degree range to acquire a first set of projection data, and the second imaging source emits beams in the 100-180 degree range to acquire a second set of projection data. The imaging control system sends the two sets of data to an image reconstruction workstation, which fuses the two sets of data using a metal artifact correction algorithm based on the projection domain to generate a three-dimensional image with suppressed metal artifacts.

[0085] For example, in image-guided localization of head and neck tumors, ring-shaped metallic dental fillings can easily cause severe stripe artifacts in cone-beam computed tomography (CBCT) images. The imaging control system sets the exit angle range of the first imaging source to 20 to 70 degrees and the exit angle range of the second imaging source to 110 to 160 degrees. These two ranges do not overlap and are symmetrically distributed anterior-posteriorly to the patient. After acquisition, the imaging control system uses an iterative reconstruction algorithm to jointly reconstruct the two sets of projection data. It utilizes complementary information from both perspectives to correct for projection data loss and distortion caused by the metallic filling, obtaining a clear three-dimensional image of the anatomical structure for subsequent positioning verification.

[0086] In one optional embodiment, controlling multiple imaging X-ray sources to trigger beam emission according to a target operating mode includes: when the target operating mode is a multi-source joint overlap mode, controlling at least two of the multiple imaging X-ray sources to trigger beam emission simultaneously, or controlling at least two of the multiple imaging X-ray sources to have an overlapping region in the angular range covered by the rotation of the annular accelerator gantry; wherein, simultaneous beam emission indicates that the beam emission time periods of at least two imaging X-ray sources overlap on the time axis; having an overlapping region in the angular range indicates that there is a common angular range between the beam emission angle ranges corresponding to each of the at least two imaging X-ray sources.

[0087] Optionally, the imaging control system can control at least two of the multiple imaging X-ray sources to simultaneously trigger beam emission. During simultaneous beam emission, the emission time periods of the at least two imaging X-ray sources overlap on the time axis. The imaging control system simultaneously sends trigger pulses to the high-voltage generators of the at least two imaging X-ray sources, causing the at least two imaging X-ray sources to output imaging X-rays within the same time period. Simultaneous beam emission can be used in dual-energy imaging scenarios, i.e., when the two imaging X-ray sources have different operating voltages, simultaneous beam emission can acquire projection data of different energies at the same angle, which is beneficial for subsequent material decomposition processing.

[0088] Optionally, the imaging control system can control at least two of the multiple imaging X-ray sources to have an overlapping region in the angular range covered by the rotation of the ring accelerator gantry. For example, the overlapping region may refer to a common angular range between the exit angle range of the first imaging X-ray source and the exit angle range of the second imaging X-ray source.

[0089] In certain imaging scenarios, simultaneous irradiation from two X-ray sources with different energies or focal points can acquire richer information. For example, when the first imaging X-ray source is configured with an 80 kV low-energy output and the second imaging X-ray source is configured with a 140 kV high-energy output, simultaneous beam emission from both sources can acquire dual-energy projection data at the same angle. Analysis of this dual-energy data allows for the differentiation of soft tissue, bone, and contrast agents by utilizing the attenuation differences of different substances to high-energy and low-energy X-rays. This facilitates material decomposition and tissue component identification, thereby improving image contrast and the accuracy of dose calculation, enabling more precise target delineation and dose calculation.

[0090] For example, when imaging the chest and abdomen of large patients, the cone-beam coverage of a single X-ray source may be insufficient to completely cover the region of interest. When it is necessary to expand the imaging field of view or enhance the data density within a specific angular range, the exit angle range of the first imaging X-ray source can be set to 0 to 120 degrees, and the exit angle range of the second imaging X-ray source can be set to 60 to 180 degrees, with the two exit angle ranges overlapping within the 60 to 120 degree range. During the rotation of the ring accelerator gantry, within the overlapping angle range, the two imaging X-ray sources can exit separately or simultaneously, thus doubling the projection data density within that angle range or obtaining dual-view information. Angle overlap configuration helps improve image quality in the peripheral areas of the field of view, or optimize reconstruction for specific anatomical sites such as the chest or head, improving image uniformity and spatial resolution. Through multi-source joint overlap mode, the imaging control system can achieve redundant or complementary acquisition of information in the temporal or spatial angular dimensions. The imaging control system fuses and registers the two sets of projection data within the overlapping angle range, which helps to expand the effective imaging field of view, enabling the reconstructed three-dimensional image to completely cover a large range of anatomical structures and meet the image guidance needs of obese patients.

[0091] In one optional embodiment, the plurality of imaging X-ray sources include a first imaging X-ray source and a second imaging X-ray source, which are arranged circumferentially along the annular accelerator frame. The method further includes: the imaging control system can acquire the current angle value between the first imaging X-ray source and the second imaging X-ray source; and adjust the current angle value to a target angle value according to the imaging part of the target object, wherein the target angle value ranges from 90° to 180°.

[0092] Optionally, the current included angle value can refer to the relative angular interval between the two imaging beam sources in the circumferential direction of the annular accelerator gantry. Different imaging locations and different imaging targets have different requirements for projection geometry, and obtaining the current included angle value can help. If the included angle is too small, the projection viewing angles of the two imaging beam sources will be too close, increasing information redundancy and reducing complementarity; if the included angle is too large, it may lead to incomplete coverage of the projection field of view or data loss during image reconstruction. By obtaining the current included angle value, the imaging control system can understand the current geometric configuration status.

[0093] Optionally, different imaging sites have different anatomical shapes and sizes, and therefore varying sensitivities to projection geometry. For example, in chest imaging, the chest has significant differences in anteroposterior and lateral diameters in cross-section. Using an angle of approximately 120 degrees can effectively balance visual field coverage and artifact suppression, allowing the projection directions of the two imaging X-ray sources to penetrate the thoracic cavity from the anterior and posterior oblique directions, respectively, thus reducing artifacts caused by skeletal obstruction. For head imaging, the head is approximately spherical with intricate internal structures. Using a larger angle of approximately 150 degrees can enhance information complementarity in the anterior-posterior direction, making the projection directions of the two imaging X-ray sources more orthogonal, which is beneficial for improving spatial resolution and contrast. By adjusting the angle according to the imaging site, the imaging control system can optimize projection geometry parameters for different anatomical regions, contributing to improved reconstruction quality and diagnostic value of 3D images.

[0094] For example, when preparing for image-guided localization of a chest tumor on a patient, the operator selects the chest as the target imaging site in the console software. The imaging control system reads the current angle between the first and second imaging sources as 90 degrees. Based on a preset site-to-angle mapping table, the system determines the target angle value corresponding to the chest imaging to be 120 degrees. The imaging control system then controls a motor drive mechanism mounted on the circular accelerator gantry to slide the second imaging source 30 degrees along the circumferential guide rail, adjusting the angle between the first and second imaging sources to 120 degrees, and then begins data acquisition for a chest cone-beam computed tomography (CBCT) scan.

[0095] For example, during image-guided stereotactic radiotherapy of the head, the operator selects the head as the target imaging site. The imaging control system detects that the angle between the first and second imaging sources is 90 degrees. Based on a preset configuration, the system determines the target angle for head imaging to be 150 degrees. The imaging control system then controls a drive motor to move the second imaging source 60 degrees circumferentially, adjusting the angle to 150 degrees. After adjustment, the imaging control system performs a head scan, with the two imaging sources emitting beams within their respective angular ranges. The acquired dual-view projection data is used to reconstruct a high-spatial-resolution three-dimensional image of the head, which is beneficial for subsequent target localization.

[0096] In one optional embodiment, at least two of the plurality of imaging X-ray sources have different operating voltages, and controlling at least one of the plurality of imaging X-ray sources to trigger beam emission includes: the imaging control system can control at least two imaging X-ray sources with different operating voltages to emit beams simultaneously, wherein the imaging X-ray sources with different operating voltages are used to enable the at least two imaging X-ray sources to output imaging X-rays of different energies.

[0097] For example, the first imaging source can be configured to output low-energy X-rays at an operating voltage of 80 kV, and the second imaging source can be configured to output high-energy X-rays at an operating voltage of 140 kV. Single-energy X-ray imaging cannot distinguish tissue structures composed of different materials, therefore, imaging sources with different operating voltages can be controlled to output beams simultaneously. In traditional single-energy imaging, bone, soft tissue, and contrast agent have similar gray values ​​in the image, making effective separation difficult. When dual-energy imaging is used, low-energy X-rays attenuate at different materials differently, while high-energy X-rays attenuate at different materials differently. By analyzing the attenuation difference between low-energy projection data and high-energy projection data acquired at the same angle, bone, soft tissue, and contrast agent can be effectively separated, generating material decomposition images. Material decomposition helps to more accurately delineate the tumor target area, reduce misjudgments caused by bone occlusion, and also helps to more accurately convert computed tomography values ​​into electron density for radiotherapy dose calculation. Dual-energy imaging can also be used for various clinical applications such as contrast agent removal, virtual plain scan, and metal artifact suppression.

[0098] Optionally, by controlling two imaging X-ray sources with different operating voltages to emit beams simultaneously, the imaging control system can simultaneously acquire low-energy projection datasets and high-energy projection datasets during a single gantry rotation. The two datasets are spatially aligned, eliminating the need for subsequent registration. Compared to time-division acquisition, which involves scanning once with low energy followed by once with high energy, simultaneous beam emission offers higher acquisition efficiency and better data consistency. This helps avoid image misalignment caused by target object movement or organ motion, thereby improving the accuracy and reliability of dual-energy analysis.

[0099] In one optional embodiment, at least two of the plurality of imaging X-ray sources have different focal sizes, and controlling at least one of the plurality of imaging X-ray sources to trigger beam emission includes: the imaging control system can control at least two imaging X-ray sources with different focal sizes to emit beams respectively, wherein the imaging X-ray source with a smaller focal size is used for high-resolution imaging, and the imaging X-ray source with a larger focal size is used for high-power imaging.

[0100] Optionally, the focal size can refer to the size of the X-ray focal spot produced when the electron beam in the imaging X-ray source bombards the target surface. Imaging X-ray sources with smaller focal sizes are used for high-resolution imaging, while those with larger focal sizes are used for high-power imaging. There is an inherent trade-off between focal size and spatial resolution and maximum output power, allowing for the configuration of imaging X-ray sources with different focal sizes. Small focal sizes produce X-rays with less geometric blurring, providing higher spatial resolution and facilitating the display of fine anatomical structures such as bone trabeculae, lung texture, or vascular details. However, small focal sizes have limited heat dissipation capacity, making it difficult to handle high tube currents, resulting in lower output power, longer scan times, or higher image noise. While large focal sizes have greater geometric blurring and relatively lower spatial resolution, they have stronger heat dissipation capacity, can handle higher tube currents, and can output higher X-ray doses in a shorter time, which is beneficial for shortening scan times, penetrating larger targets, or reducing image noise. By configuring two imaging X-ray sources with different focal sizes within the same system, the imaging control system can flexibly select the appropriate X-ray source according to clinical needs. Specifically, a small-focal-size source can be used to obtain high-resolution images when observing fine anatomical structures; a large-focal-size source can be used to ensure image quality and scanning efficiency when imaging larger targets or requiring rapid scanning. This differentiated configuration helps achieve a balance between image quality and radiation dose in different clinical application scenarios.

[0101] For example, when performing stereotactic radiotherapy for acoustic neuroma localization, it is necessary to clearly visualize the delicate nerve and vascular structures within the internal auditory canal. The imaging control system selects a first imaging X-ray source with a focal size of 0.3 mm × 0.3 mm as the output beam source. During the rotation of the circular accelerator gantry, the first imaging X-ray source outputs a beam to acquire projection data, and the reconstructed three-dimensional image has high spatial resolution, clearly showing the boundary between the tumor and surrounding nerves, assisting doctors in accurately delineating the target area.

[0102] For example, when performing image-guided abdominal tumor imaging on obese patients with a body mass index (BMI) exceeding 30, the large body size makes X-ray penetration difficult. The imaging control system selects a second imaging X-ray source with a focal size of 0.8 mm × 0.9 mm as the output beam source. The second imaging X-ray source outputs the beam with a higher tube current, providing a sufficient X-ray dose in a shorter time, enabling the flat panel detector to obtain projection data with sufficient signal and low noise. The reconstructed three-dimensional image meets the image quality requirements for clinical positioning verification.

[0103] In an alternative embodiment, the method further includes: after the imaging control system reconstructs a three-dimensional image based on the projection data, it controls a retractable mechanism to drive multiple imaging ray sources to move from a second position to a first position.

[0104] Optionally, in the second position, multiple imaging beam sources extend beyond the inner wall of the annular accelerator gantry, positioned in a suitable working position for emitting imaging beams; in the first position, multiple imaging beam sources are located within the annular accelerator gantry cavity or flush with the inner wall, in a retracted state. After image-guided verification or dynamic tracking imaging is completed, the next treatment stage may require the main treatment beam source to emit a beam for treatment, therefore, the imaging beam sources need to be retracted to the first position after reconstructing the 3D image. If the imaging beam sources remain in the second position, extending beyond the inner wall, the extended imaging beam sources may physically interfere with the rotating treatment head or obstruct the path of the treatment beam. By retracting the imaging beam sources to the first position, flush with the inner wall or fully retracted into the gantry cavity, space is made for the free movement of the treatment head and the safe emission of the main treatment beam source. Retraction helps ensure that all imaging-related hardware has been returned to a safe clearance position before the start of the treatment stage, thereby ensuring the safety of the treatment process and the normal operation of the equipment.

[0105] For example, after completing the 3D image reconstruction for patient positioning verification, the imaging control system confirms that the image quality meets clinical requirements. The imaging control system sends a retraction command to the motor-driven lead screw mechanism, causing the motor to rotate in the opposite direction. This moves the sliders fixedly connected to the first and second imaging X-ray sources inward along the guide rail, retracting the first and second imaging X-ray sources from a second position extending beyond the inner wall to a first position flush with the inner wall of the annular accelerator gantry. After confirming the X-ray sources are in position, the imaging control system sends an imaging system ready signal to the treatment control system, allowing the commencement of subsequent radiotherapy.

[0106] For example, after respiratory-gated imaging is completed and a dynamic three-dimensional image is successfully reconstructed, the treatment planning system updates the target area position based on the image. The imaging control system triggers a pneumatic control valve to reverse, and a cylinder drives the telescopic arm to move in the opposite direction, retracting multiple imaging beam sources from their extended state to a first position housed within the annular accelerator gantry. Once the retraction positioning sensor located on the telescopic path is triggered, the imaging control system locks the telescopic mechanism and then controls the main treatment beam source to begin firing for treatment.

[0107] See Figure 3 According to another aspect of the embodiments of this application, a multi-source cooperative imaging device on a ring accelerator is also provided, including a first acquisition unit, a first processing unit, a second processing unit, a third processing unit and a fourth processing unit.

[0108] The system comprises the following components: a first acquisition unit for acquiring the operating status of the main therapeutic beam source and the rotation angle data of the annular accelerator gantry; a first processing unit for controlling a retractable mechanism to move multiple imaging beam sources mounted on the inner wall of the annular accelerator gantry from a first position to a second position when the main therapeutic beam source is in standby mode, wherein in the first position, the imaging beam source is located inside the annular accelerator gantry or flush with the inner wall; in the second position, the imaging beam source extends beyond the inner wall; a second processing unit for controlling at least one of the multiple imaging beam sources to trigger beam emission based on the rotation angle data; a third processing unit for controlling multiple flat panel detectors to receive imaging beams passing through the target object and acquiring projection data generated by the multiple flat panel detectors, wherein the multiple flat panel detectors are mounted on the annular accelerator gantry, and each flat panel detector is positioned opposite to at least one imaging beam source; and a fourth processing unit for determining a three-dimensional image based on the projection data.

[0109] Optionally, the second processing unit includes: a first processing subunit, configured to determine the current angle range of the annular accelerator gantry based on rotation angle data; a second processing subunit, configured to control at least one of the multiple imaging X-ray sources to trigger beam emission according to a preset timing sequence when the angle range falls within a preset trigger angle window, wherein the preset timing sequence indicates that the triggering time and beam emission duration of each imaging X-ray source are configured according to a preset time relationship; and a third processing subunit, configured to control the multiple imaging X-ray sources to stop beam emission when the angle range does not fall within the trigger angle window.

[0110] Optionally, the second processing subunit includes: a first processing module for determining a target operating mode from multiple operating modes, wherein the multiple operating modes include at least two of a single-source operating mode, a multi-source synchronous alternating mode, a multi-source time-division coordinating mode, and a multi-source joint overlapping mode; and a second processing module for controlling multiple imaging X-ray sources to trigger beam output according to the target operating mode.

[0111] Optionally, the first processing module includes: a first acquisition submodule, configured to acquire the position signal of a mode switching switch, wherein the mode switching switch has at least two positions, and each of the at least two positions corresponds to a different imaging X-ray source working mode; and the first processing submodule is configured to determine the target working mode based on the position signal.

[0112] Optionally, the first processing module includes: a second acquisition submodule for acquiring respiratory gating signals or tumor tracking instructions; and a second processing submodule for dynamically selecting a target working mode based on the respiratory gating signals or tumor tracking instructions.

[0113] Optionally, the second processing module includes: a third processing submodule, used to control at least two of the multiple imaging X-ray sources to alternately emit beams according to a preset alternation cycle when the target working mode is a multi-source synchronous alternation mode, wherein the alternation cycle characterizes the time required for each imaging X-ray source to complete one beam emission cycle in sequence, and during the alternating beam emission process, only one imaging X-ray source is in the beam emission state at any given time.

[0114] Optionally, the second processing module includes: a fourth processing submodule, used to control at least two of the multiple imaging X-ray sources to trigger beams in different angle intervals of the rotation of the annular accelerator gantry when the target working mode is a multi-source time-division coordinating mode, wherein the angle intervals have a preset interval angle or do not overlap.

[0115] Optionally, the second processing module includes: a fifth processing submodule, configured to, when the target operating mode is a multi-source joint overlap mode, control at least two of the multiple imaging X-ray sources to simultaneously trigger beam emission, or control at least two of the multiple imaging X-ray sources to have an overlapping region in the angular range covered by the rotation of the annular accelerator gantry; wherein, simultaneous beam emission indicates that the beam emission time periods of the at least two imaging X-ray sources overlap on the time axis; having an overlapping region in the angular range indicates that there is a common angular range between the beam emission angle ranges corresponding to the at least two imaging X-ray sources.

[0116] Optionally, the multiple imaging X-ray sources include a first imaging X-ray source and a second imaging X-ray source, which are arranged circumferentially along the ring accelerator frame. The multi-source collaborative imaging device on the ring accelerator further includes: a second acquisition unit for acquiring the current angle value between the first imaging X-ray source and the second imaging X-ray source; and a fifth processing unit for adjusting the current angle value to a target angle value according to the imaging part of the target object, wherein the target angle value ranges from 90° to 180°.

[0117] Optionally, at least two of the multiple imaging X-ray sources have different operating voltages. The second processing unit includes a fourth processing subunit for controlling the at least two imaging X-ray sources with different operating voltages to emit beams simultaneously. The imaging X-ray sources with different operating voltages are used to enable the at least two imaging X-ray sources to output imaging X-rays with different energies.

[0118] Optionally, at least two of the multiple imaging X-ray sources have different focal sizes. The second processing unit includes a fifth processing subunit for controlling the at least two imaging X-ray sources with different focal sizes to emit beams respectively, wherein the imaging X-ray source with a smaller focal size is used for high-resolution imaging, and the imaging X-ray source with a larger focal size is used for high-power imaging.

[0119] Optionally, the multi-source collaborative imaging device on the ring accelerator further includes: a sixth processing unit, used to control a retractable mechanism to drive multiple imaging ray sources from a second position to a first position after reconstructing a three-dimensional image based on projection data.

[0120] According to another aspect of the embodiments of this application, a computer-readable storage medium is also provided, which stores a computer program, wherein when the computer program is executed, the device on which the computer-readable storage medium is located executes the above-described multi-source cooperative imaging method on a ring accelerator.

[0121] According to another aspect of the embodiments of this application, an electronic device is also provided, including one or more processors and a memory, the memory being used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to perform the above-described multi-source cooperative imaging method on a ring accelerator.

[0122] According to another aspect of the embodiments of this application, a computer program product is also provided, including a computer program or instructions that, when executed by a processor, implement the above-described multi-source cooperative imaging method on a ring accelerator.

[0123] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0124] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0125] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0126] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0127] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0128] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0129] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A multi-source cooperative imaging method on a circular accelerator, characterized in that, include: Acquire the working status of the main therapeutic beam source and the rotation angle data of the annular accelerator gantry; When the main therapeutic beam source is in standby mode, the control telescopic mechanism drives multiple imaging beam sources disposed on the inner wall of the annular accelerator gantry to move from a first position to a second position. In the first position, the imaging beam source is located in the inner cavity of the annular accelerator gantry or flush with the inner wall. In the second position, the imaging beam source extends out of the inner wall. Based on the rotation angle data, at least one of the plurality of imaging X-ray sources is controlled to trigger beam emission; Multiple flat panel detectors are controlled to receive imaging rays passing through the target object and to acquire projection data generated by the multiple flat panel detectors, wherein the multiple flat panel detectors are disposed on the annular accelerator gantry, and each of the flat panel detectors is disposed opposite to at least one imaging ray source; A three-dimensional image is determined based on the projection data.

2. The multi-source cooperative imaging method on a circular accelerator according to claim 1, characterized in that, Based on the rotation angle data, controlling at least one of the multiple imaging X-ray sources to trigger beam emission includes: Based on the rotation angle data, the current angle range of the annular accelerator frame is determined; When the angle range falls within a preset trigger angle window, at least one of the plurality of imaging X-ray sources is controlled to trigger beam emission according to a preset timing sequence, wherein the preset timing sequence indicates that the triggering time and beam emission duration of each imaging X-ray source are configured according to a preset time relationship. When the angle range does not belong to the trigger angle window, the plurality of imaging X-ray sources are controlled to stop emitting beams.

3. The multi-source cooperative imaging method on a circular accelerator according to claim 2, characterized in that, Controlling at least one of the plurality of imaging X-ray sources to trigger beam emission according to a preset timing sequence includes: The target working mode is determined from multiple working modes, wherein the multiple working modes include at least two of the following: single-source working mode, multi-source synchronous alternation mode, multi-source time-sharing coordination mode, and multi-source joint overlap mode; The plurality of imaging X-ray sources are controlled to trigger beam output according to the target operating mode.

4. The multi-source cooperative imaging method on a circular accelerator according to claim 3, characterized in that, Determine the target work mode from multiple work modes, including: Acquire the position signal of the mode switching switch, wherein the mode switching switch has at least two positions, and each of the at least two positions corresponds to a different imaging X-ray source working mode. The target operating mode is determined based on the gear position signal.

5. The multi-source cooperative imaging method on a circular accelerator according to claim 3, characterized in that, Determine the target work mode from multiple work modes, including: Acquire respiratory gating signals or tumor tracking instructions; The target working mode is dynamically selected based on the respiratory gating signal or the tumor tracking instruction.

6. The multi-source cooperative imaging method on a circular accelerator according to claim 3, characterized in that, Controlling the multiple imaging X-ray sources to trigger beam output according to the target operating mode includes: When the target working mode is a multi-source synchronous alternating mode, at least two of the multiple imaging X-ray sources are controlled to alternately emit beams according to a preset alternation period. The alternation period represents the time required for each imaging X-ray source to complete one beam emission cycle in sequence. During the alternating beam emission process, only one imaging X-ray source is in the beam emission state at any given time.

7. The multi-source cooperative imaging method on a ring accelerator according to claim 3, characterized in that, Controlling the multiple imaging X-ray sources to trigger beam output according to the target operating mode includes: When the target working mode is a multi-source time-division cooperative mode, at least two of the multiple imaging X-ray sources are controlled to trigger beams in different angle intervals of the rotation of the annular accelerator gantry, wherein each angle interval has a preset interval angle or does not overlap.

8. The multi-source cooperative imaging method on a circular accelerator according to claim 3, characterized in that, Controlling the multiple imaging X-ray sources to trigger beam output according to the target operating mode includes: When the target operating mode is a multi-source joint overlap mode, at least two of the multiple imaging X-ray sources are controlled to simultaneously trigger beam emission, or at least two of the multiple imaging X-ray sources are controlled to have an overlapping region in the angular range covered by the rotation of the annular accelerator gantry; wherein, the simultaneous triggering of beam emission indicates that the beam emission time periods of the at least two imaging X-ray sources overlap on the time axis; the overlapping region in the angular range indicates that there is a common angular range between the beam emission angle ranges corresponding to the at least two imaging X-ray sources.

9. The multi-source cooperative imaging method on a circular accelerator according to claim 1, characterized in that, The plurality of imaging X-ray sources includes a first imaging X-ray source and a second imaging X-ray source, the first imaging X-ray source and the second imaging X-ray source being arranged circumferentially along the annular accelerator gantry, and the method further includes: Obtain the current angle value between the first imaging X-ray source and the second imaging X-ray source; Based on the imaging location of the target object, the current included angle value is adjusted to the target included angle value, wherein the range of the target included angle value is 90° to 180°.

10. The multi-source cooperative imaging method on a circular accelerator according to claim 1, characterized in that, At least two of the plurality of imaging X-ray sources have different operating voltages, and controlling at least one of the plurality of imaging X-ray sources to trigger beam emission includes: The at least two imaging X-ray sources with different operating voltages are controlled to emit beams simultaneously, wherein the imaging X-ray sources with different operating voltages are used to make the at least two imaging X-ray sources output imaging X-rays with different energies.

11. The multi-source cooperative imaging method on a circular accelerator according to claim 1, characterized in that, At least two of the plurality of imaging X-ray sources have different focal lengths, and controlling at least one of the plurality of imaging X-ray sources to trigger beam emission includes: The at least two imaging X-ray sources with different focal sizes emit beams respectively, wherein the imaging X-ray source with a smaller focal size is used for high-resolution imaging, and the imaging X-ray source with a larger focal size is used for high-power imaging.

12. The multi-source cooperative imaging method on a circular accelerator according to claim 1, characterized in that, The method further includes: After reconstructing the three-dimensional image based on the projection data, the retractable mechanism is controlled to drive the plurality of imaging ray sources to move from the second position to the first position.

13. A multi-source cooperative imaging device on a circular accelerator, characterized in that, include: The first acquisition unit is used to acquire the working status of the main therapeutic beam source and the rotation angle data of the annular accelerator gantry; The first processing unit is configured to, when the main therapeutic beam source is in standby mode, control a retractable mechanism to drive multiple imaging beam sources disposed on the inner wall of the annular accelerator gantry to move from a first position to a second position, wherein, in the first position, the imaging beam source is located in the inner cavity of the annular accelerator gantry or flush with the inner wall; in the second position, the imaging beam source extends out of the inner wall. The second processing unit is used to control at least one of the plurality of imaging X-ray sources to trigger beam output based on the rotation angle data; The third processing unit is used to control multiple flat panel detectors to receive imaging rays passing through the target object and to acquire projection data generated by the multiple flat panel detectors, wherein the multiple flat panel detectors are disposed on the annular accelerator frame, and each of the flat panel detectors is disposed opposite to at least one imaging ray source. The fourth processing unit is used to determine a three-dimensional image based on the projection data.

14. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, wherein when the computer program is executed, the device on which the computer-readable storage medium is located performs the multi-source cooperative imaging method on a circular accelerator as described in any one of claims 1 to 12.

15. An electronic device, characterized in that, It includes one or more processors and a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors cause the one or more processors to perform the multi-source cooperative imaging method on a ring accelerator as described in any one of claims 1 to 12.

16. A computer program product, characterized in that, It includes a computer program or instructions that, when executed by a processor, implement the multi-source cooperative imaging method on a ring accelerator according to any one of claims 1 to 12.

Images