Target real-time tracking control method and electronic device

Abstract

The present disclosure provides a target real-time tracking control method and an electronic device, and belongs to the technical field of radiotherapy device control. The method comprises: acquiring a beam-out direction of a current treatment beam; constructing a follow-up coordinate system that changes with the beam view angle based on the beam-out direction, wherein the follow-up coordinate system takes the isocenter of the radiotherapy device as the origin, at least includes a first coordinate axis and a second coordinate axis perpendicular to each other, and the beam-out direction is perpendicular to the plane formed by the first coordinate axis and the second coordinate axis; determining the two-dimensional offset of the target on the first coordinate axis and the second coordinate axis, and controlling the radiotherapy device based on the two-dimensional offset. The present disclosure can accurately determine the two-dimensional offset of the target which has a significant influence on the treatment quality.

Description

Technical Field

[0001] This disclosure relates to the field of radiotherapy equipment control technology, and in particular to a real-time target tracking control method and electronic device. Background Technology

[0002] Intraoperative image-guided radiotherapy (IRRT) involves acquiring real-time projected images of the tumor and registering them with reference images to calculate tumor positional deviations and control the treatment process accordingly. It is a core technology for ensuring the precision and safety of radiotherapy. Current technologies generally use a fixed coordinate system conforming to the IEC 61217 standard to characterize the tumor's three-dimensional positional offset and use this as the basis for radiotherapy control.

[0003] However, three-dimensional deviations in a fixed coordinate system do not distinguish the actual impact of offsets in different directions on the treatment effect, which may lead to accidental treatment interruption, affecting treatment efficiency, or may cause insufficient dose to the target area or excessive dose to normal tissues, affecting treatment quality. Summary of the Invention

[0004] This disclosure provides a real-time target tracking and control method and electronic device that can accurately determine the two-dimensional offset that actually affects the treatment effect.

[0005] The technical solution disclosed herein is implemented as follows: In a first aspect, this disclosure provides a real-time target tracking and control method, the method comprising: acquiring the exit direction of the current treatment beam; constructing a follow-up coordinate system that changes with the beam angle based on the exit direction, wherein the follow-up coordinate system takes the isocenter of the radiotherapy device as the origin, includes at least a first coordinate axis and a second coordinate axis that are perpendicular to each other, and the exit direction is perpendicular to the plane formed by the first coordinate axis and the second coordinate axis; determining the two-dimensional offset of the target on the first coordinate axis and the second coordinate axis, so as to control the radiotherapy device based on the two-dimensional offset.

[0006] Secondly, this disclosure provides a real-time target tracking and control device, comprising: an acquisition section configured to acquire the exit direction of a current treatment beam; a construction section configured to construct a servo coordinate system that changes with the beam angle based on the exit direction, wherein the servo coordinate system has its origin at the isocenter of the radiotherapy device and includes at least a first coordinate axis and a second coordinate axis that are perpendicular to each other, and the exit direction is perpendicular to the plane formed by the first coordinate axis and the second coordinate axis; and a determination section configured to determine a two-dimensional offset of the target on the first coordinate axis and the second coordinate axis, so as to control the radiotherapy device based on the two-dimensional offset.

[0007] Thirdly, this disclosure provides an electronic device including a processor, a memory, and a program or instructions stored in the memory and executable on the processor, wherein the program or instructions, when executed by the processor, implement the steps of the real-time target tracking control method as described in the first aspect.

[0008] Fourthly, this disclosure provides a computer-readable storage medium on which a program or instructions are stored, which, when executed by a processor, implement the steps of the real-time target tracking and control method as described in the first aspect.

[0009] This disclosure provides a real-time target tracking and control method, an electronic device, and a computer-readable storage medium. The method constructs a dynamic coordinate system that updates in real-time with the current treatment beam's exit direction. The plane defined by this dynamic coordinate system is strictly perpendicular to the exit direction, eliminating interference from offset components along the exit direction on treatment control decisions. Only the two-dimensional offset within the BeamView plane, which truly affects the dose distribution, is used as the control basis for the radiotherapy equipment. On the one hand, this avoids unnecessary treatment interruptions or patient position corrections triggered by deviations along the exit direction that have no actual therapeutic significance. On the other hand, it solves the problem of missed detections where the overall error value is small under a fixed coordinate system, but the actual dose-affected offset within the BeamView plane is large. This significantly improves the treatment efficiency and patient experience of radiotherapy while ensuring treatment accuracy. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the system architecture of a real-time target tracking and control system provided in this disclosure.

[0011] Figure 2 This is a schematic diagram of the composition of an electronic device provided in an embodiment of this disclosure.

[0012] Figure 3 This is a flowchart illustrating a real-time target tracking and control method provided in this disclosure.

[0013] Figure 4 This is a schematic diagram of the follower coordinate system established based on the beam output direction provided in this disclosure.

[0014] Figure 5 A schematic diagram illustrating the determination of the beam output direction provided in this disclosure.

[0015] Figure 6 This is a schematic diagram of the following coordinate system, including the third coordinate axis, provided in this disclosure.

[0016] Figure 7 A flowchart illustrating another real-time target tracking and control method provided in this disclosure.

[0017] Figure 8This is a schematic diagram illustrating the principle of determining two-dimensional offset based on a single projected image, as provided in this disclosure.

[0018] Figure 9 This is a structural block diagram of a real-time target tracking and control device provided in this disclosure. Detailed Implementation

[0019] The technical solutions in the embodiments of this disclosure will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure are within the scope of protection of this disclosure.

[0020] The terms “first,” “second,” etc., used in this disclosure are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that this disclosure can be implemented in orders other than those illustrated or described herein, and the objects distinguished by “first,” “second,” etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more.

[0021] To facilitate understanding of the technical solutions of the embodiments of this disclosure, the related technologies of the embodiments of this disclosure are described below. The following related technologies are optional solutions and can be combined with the technical solutions of the embodiments of this disclosure in any way, and they all fall within the protection scope of the embodiments of this disclosure.

[0022] In related technologies, intraoperative image-guided radiotherapy systems typically use a fixed coordinate system conforming to the IEC 61217 standard to characterize the three-dimensional positional offset of the tumor, and use this three-dimensional offset as the basis for judging the control of radiotherapy.

[0023] In actual radiotherapy, the treatment beam propagates along its optical axis, and the effect of tumor position deviation on dose distribution varies directionally. Deviation perpendicular to the beam's optical axis causes an overall shift in dose distribution, thereby altering the radiation dose received by the target area and surrounding normal tissues. Deviation along the beam's optical axis has a relatively small impact on target area dose coverage and is within an acceptable range in most clinical scenarios.

[0024] In rotational radiotherapy modes such as volumetric intensity-modulated radiotherapy (IMRT) and rotating gamma knife, the direction of the treatment beam dynamically changes with the rotation of the gantry, and the relative angles between the three coordinate axes of the fixed coordinate system of the radiotherapy equipment and the current beam optical axis continuously change. In this case, the three-dimensional offset in the fixed coordinate system cannot directly reflect the effective degree of tumor offset relative to the current beam's plane of action.

[0025] Existing technologies do not differentiate the actual impact of deviations in different directions on treatment effects and uniformly use three-dimensional offset for control. This may lead to offsets along the beam optical axis that have no significant dose effect being included in the judgment criteria, triggering unnecessary treatment interruptions or bed adjustments and reducing treatment efficiency. When the three-dimensional offset in the fixed coordinate system does not exceed the preset threshold, but the offset component perpendicular to the beam plane exceeds the allowable range, it is impossible to identify and take intervention measures in time, which may also lead to insufficient dose to the target area or excessive dose to normal tissues.

[0026] To address the aforementioned technical problems, this disclosure provides a real-time target tracking and control method. Before detailing the method, the application environment involved in this disclosure embodiment will first be described.

[0027] The method provided in this disclosure can be applied to radiotherapy systems, such as... Figure 1 As shown, Figure 1 This is a schematic diagram of a system architecture for a real-time target tracking and control system provided in an embodiment of the present disclosure. In some embodiments, the real-time target tracking and control system may include a radiotherapy device 100 and an electronic device 200. The radiotherapy device 100 and the electronic device 200 establish a communication connection via wired or wireless means.

[0028] Specifically, the radiotherapy device 100 may include a patient support device 101, a gantry 102, and an imaging device (i.e., an image-guided system) mounted on the gantry 102. The imaging device is used to acquire real-time projected images or three-dimensional tomographic images of the target to calculate the spatial positional offset of the target (e.g., a tumor lesion in the patient's body, an implanted marker, or a gold marker, etc.). The imaging device includes various component types based on different imaging principles.

[0029] The X-ray imaging components correspond to kilovolt (KV) level projection imaging and computed tomography (CT) imaging methods, specifically including digital radiography (DR) imaging components, cone-beam computed tomography (CBCT) imaging components, computed tomography (CT) imaging components, volumetric CT imaging components, and positron emission tomography (PET) imaging components. Optical imaging components correspond to infrared imaging and body surface imaging methods, specifically including infrared optical imaging components and optical body surface imaging components. Ultrasound imaging components correspond to ultrasound imaging methods, specifically including two-dimensional ultrasound imaging components and three-dimensional ultrasound imaging components. Magnetic resonance imaging components correspond to nuclear magnetic resonance imaging methods, specifically including magnetic resonance imaging (MRI) imaging components. Imaging devices may include any of the above component types, or combinations thereof.

[0030] like Figure 1 As shown, an example is given of an imaging device comprising a set of CBCT imaging components. A set of CBCT imaging components includes an X-ray tube 103 and a detector 104 arranged opposite each other, constituting a single-channel (single-kV) imaging system. The X-ray tube 103 and detector 104 are mounted on the gantry 102 of the radiotherapy equipment 100 and can rotate 360 ​​degrees with the gantry, completing the CBCT scan during rotation. In other examples, the imaging device may also include multiple sets, such as two sets of CBCT imaging components, including two sets of X-ray tubes and detectors arranged opposite each other, constituting a dual-channel (dual-kV) imaging system. The central axes of the two sets of CBCT imaging components in the dual-channel (dual-kV) imaging system are at a preset angle, for example, any angle between 80 degrees and 120 degrees. The central axis is the line connecting the focal point of one X-ray tube and the center point of one detector.

[0031] In some examples, the X-ray tube 103 emits an imaging beam at a low frame rate during the treatment beam output process, such as 2 to 6 frames per second, emitting kilovolt (KV) level X-rays. The KV level X-rays can be a cone beam. The detector 104 can be a flat panel detector or a curved surface detector. The detector 104 is used to receive the KV level X-rays (optical signals) after passing through the treatment area and convert the optical signals into electrical signals to be sent to the electronic device 200 to generate a projected image of the target.

[0032] The patient support device 101 can support the patient P and also position the patient P. For example, the patient support device 101 can be a three-dimensional, four-dimensional, five-dimensional, or six-dimensional treatment bed or chair. Taking the patient support device 101 as a treatment bed as an example, a three-dimensional treatment bed refers to a device that can be positioned in three orthogonal directions (e.g.,...). Figure 1 A treatment bed that can translate in the X, Y, and Z directions (as shown in the diagram); a four-dimensional treatment bed is a treatment bed that can translate in three orthogonal directions and rotate in any one of the three orthogonal directions; a five-dimensional treatment bed is a treatment bed that can translate in three orthogonal directions and rotate in any two of the three orthogonal directions; a six-dimensional treatment bed is a treatment bed that can translate in three orthogonal directions and rotate in three orthogonal directions.

[0033] In some embodiments of this disclosure, when patient P lies flat on the treatment bed of radiotherapy device 100, the three-dimensional coordinate system is defined as follows: the X-axis is the left-right direction of the patient, the Y-axis is the head-to-toe direction of the patient, also known as the depth direction, and the Z-axis is the front-back direction of the patient, also known as the up-down direction.

[0034] The frame 102 can drive the X-ray tube 103 and the detector 104 to rotate around the rotation axis. The frame 102 can be a ring frame, a C-arm frame, a drum frame, etc. This disclosure does not limit the structure of the frame, but only uses the example shown in the figure for illustration.

[0035] In some examples, a treatment device can also be mounted on the rack 102. This device includes a treatment head 105 and an actuator 106. The treatment head 105 emits megavolt (MV) level therapeutic X-rays or gamma rays to perform radiotherapy on the patient's treatment area (e.g., the target area). The actuator 106 can be implemented as a multi-leaf collimator, mounted on the beam exit path of the treatment head 105, to adjust the irradiation area, shape, and intensity of the therapeutic beam, thereby enabling the treatment device to emit the therapeutic beam M. By precisely controlling the irradiation position and dose of the therapeutic beam M, precise radiotherapy can be performed on the treatment area of ​​the patient P.

[0036] In some embodiments, the actuator 106 includes a multi-leaf collimator (MLC), which includes multiple sets (such as two sets) of independently movable blades and a moving carriage for carrying all the blades. The moving carriage can drive all the blades to translate as a whole along the Y-axis, and the blades can perform independent opening and closing movements under the support of the carriage. The overall translation of the moving carriage is used to compensate for the overall displacement of the tumor with respiration, and the opening and closing movements of the blades are used to maintain the conformal shape of the treatment beam, thereby decoupling the tumor tracking function from the conformal function of the treatment beam.

[0037] In some examples, the actuator 106 can also be implemented as an independent collimator, a cone collimator, etc. The actuator 106 can also be a treatment bed, gantry, or other mechanism of a radiotherapy device that can be used to adjust the relative position between the treatment beam and the patient, for example, by adjusting the incident angle and irradiation position of the treatment beam through the rotation of the gantry.

[0038] The actuators mentioned in the embodiments of this disclosure all cover mechanisms or devices that can realize relative position adjustment, and the target real-time tracking control method provided in this disclosure can be equally applied to the follow-up control of the above-mentioned types of actuators, and can also be applied to target real-time tracking scenarios of other types of radiotherapy equipment such as Gamma Knife.

[0039] In some embodiments of this disclosure, the electronic device 200 can be a standalone server, or a server network or server cluster, such as, but not limited to, a computer, a network host, a single network server, a set of multiple network servers, or a cloud server composed of multiple servers. The cloud server is composed of a large number of computers or network servers based on cloud computing. The electronic device 200 can also be a general-purpose computer device or a special-purpose computer device, such as a desktop computer, a portable computer, a network server, a PDA (Personal Digital Assistant), a mobile phone, a tablet computer, a wireless terminal device, a communication device, an embedded device, etc. This disclosure does not limit the type of electronic device 200.

[0040] In some examples, the electronic device 200 can be implemented as a controller, microcontroller, programmable logic controller (PLC), digital signal processing (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), general-purpose processor, computer, or any combination thereof. When the electronic device 200 is implemented as a controller, the controller is communicatively coupled to the radiotherapy equipment 100 and establishes data transmission links with the gantry 102, imaging device, and treatment device, respectively. The controller acquires the current beam exit direction of the treatment beam; based on the beam exit direction, it constructs a servo coordinate system with the isocenter of the radiotherapy equipment as the origin. This servo coordinate system includes at least a first coordinate axis and a second coordinate axis that are perpendicular to each other, and the beam exit direction is perpendicular to the plane formed by the first and second coordinate axes; the controller determines the two-dimensional offset of the target on the first and second coordinate axes in the servo coordinate system; and controls the corresponding actuator of the radiotherapy equipment 100 according to the two-dimensional offset to adjust the relative position between the treatment beam and the target, thereby achieving real-time tracking control of the radiotherapy process.

[0041] In some examples, the wireless communication connection methods between the radiotherapy device 100 and the electronic device 200, and between the controller and the imaging device and the treatment device respectively, include, but are not limited to: mobile communication based on 2G, 3G, 4G, 5G, Long Term Evolution (LTE), and World Wide Interoperability for Microwave Access (WiMAX), or computer network communication based on the TCP / IP protocol suite and User Datagram Protocol (UDP).

[0042] In some examples, the wireless communication connection methods between the radiotherapy device 100 and the electronic device 200, and between the controller and the imaging device and the treatment device respectively, include, but are not limited to: mobile communication based on 2G, 3G, 4G, 5G, Long Term Evolution (LTE), and World Wide Interoperability for Microwave Access (WiMAX), or computer network communication based on the TCP / IP protocol suite and User Datagram Protocol (UDP).

[0043] See Figure 2 , Figure 2 This is a schematic diagram illustrating the composition of an electronic device according to an embodiment of the present disclosure. In some embodiments, the electronic device 200 may include a processor 201, a memory 202, an input / output (I / O) interface 203, and a communication port 204. The processor 201 may include a microcontroller, a microprocessor, a reduced instruction set computer (RISC), an application-specific integrated circuit (ASIC), an application-specific instruction-set processor (ASIP), a central processing unit (CPU), a graphics processing unit (GPU), a physical processor (PPU), a microcontroller, a digital signal processor, a field-programmable gate array (FPGA), an advanced reduced instruction set system (ARM), a programmable logic device (PLD), any circuit or processor capable of performing at least one function, or any combination thereof.

[0044] Memory 202 may store data, instructions, and / or any other information. In some examples, memory 202 may store data acquired from the imaging device. In some examples, memory 202 may store data and / or instructions for performing the exemplary methods described in this disclosure. In some examples, memory 202 may include mass storage, removable memory, volatile read-write memory, read-only memory (ROM), non-volatile memory, and any combination thereof.

[0045] In addition, those skilled in the art will understand that the structure of the electronic device 200 shown in the above figures does not constitute a limitation on the electronic device 200. The electronic device 200 may include more or fewer components than shown, or combine certain components, or have different component arrangements. For example, the electronic device 200 may also include a display screen, camera assembly, microphone, speaker, radio frequency circuit, input unit, sensor, audio circuit, WiFi module, power supply, Bluetooth module, etc., which will not be described in detail here.

[0046] See Figure 3 , Figure 3 The flowchart of a real-time target tracking and control method provided in this embodiment of the present disclosure is shown. The execution subject can be the aforementioned electronic device 200, and includes steps S301 to S303.

[0047] In step S301, the exit direction of the current treatment beam is obtained.

[0048] In radiotherapy (such as volumetric intensity-modulated radiotherapy, rotating gamma knife, and other dynamic radiotherapy scenarios), the spatial position of the target (such as the tumor lesion in the patient's body, implanted markers, or gold markers) is crucial for the accurate coverage of the radiotherapy dose. Because these radiotherapy devices rotate around the patient during operation, the treatment beam emitted by the treatment head also undergoes dynamic spatial position changes accordingly.

[0049] A therapeutic beam is a high-energy beam of radiation emitted from the treatment head of a radiotherapy device to treat a target area within a patient's body. It can be megavolt-level X-rays, gamma rays, or electron beams.

[0050] The beam exit direction refers to the direction of the central axis of the treatment beam, which passes through the isocenter of the radiotherapy equipment. The isocenter of the radiotherapy equipment refers to the rotation center of the radiotherapy equipment gantry. It is a fixed spatial point through which the central axis of the treatment beam in all possible positions passes when the gantry rotates around its rotation axis. It is the positioning reference point for radiotherapy.

[0051] The electronic device can be configured to determine the direction of the treatment beam at the current moment by reading the rotation angle sensor data of the gantry of the radiotherapy equipment in real time, or by receiving the control command stream issued by the radiotherapy planning system.

[0052] In this embodiment, the electronic device can be configured to read the real-time rotation angle value of the gantry and calculate the unit direction vector of the current treatment beam in the fixed coordinate system of the device, i.e., the beam output direction, based on a preset mapping relationship between the gantry angle and the beam optical axis direction. Specifically, the electronic device can read the real-time rotation angle value of the gantry by establishing a communication link with the rotary encoder of the gantry.

[0053] In other embodiments, a six-axis attitude sensor mounted on the treatment head can be used to directly measure the beam optical axis attitude, or a laser tracking system can be used to track the spatial position of the treatment head in real time and calculate the beam direction, or a preset gantry angle sequence can be read directly from the radiotherapy planning system and the beam direction can be calculated, or the actual beam direction can be directly measured by a beam detection device installed at the isocenter, etc. This disclosure does not limit this.

[0054] The therapeutic beam has a definite directionality in its dose effect on the target. Only by accurately obtaining the current propagation direction of the therapeutic beam can a reference coordinate system directly related to the dose effect be established.

[0055] In step S302, a follower coordinate system that changes with the beam angle is constructed based on the beam output direction.

[0056] The following coordinate system refers to an orthogonal coordinate system (which can be called the BeamView coordinate system) that changes in real time with the direction of the treatment beam. It is used to characterize the positional relationship of the target relative to the current treatment beam. Every time the gantry rotates by an angle, the direction of the treatment beam changes, and the coordinate axes of the following coordinate system will also rotate synchronously in space.

[0057] To ensure that the servo coordinate system reflects the characteristics of the treatment beam, its origin is set as the isocenter of the radiotherapy equipment. The isocenter is the ideal spatial intersection of the gantry rotation axis, the treatment bed rotation axis, and the collimator rotation axis. It is a fixed spatial point through which the central axis of the treatment beam at all possible positions passes when the gantry rotates around its rotation axis; this is the center point and serves as the positioning reference point for radiotherapy. Setting the origin of the servo coordinate system at the isocenter ensures that the coordinate system's reference is consistent with the mechanical and dose references of the radiotherapy equipment.

[0058] Understandably, the plane formed by the mutually perpendicular first and second coordinate axes is the BeamView plane, which is parallel to the current treatment beam cross-section. During the penetration of the radiotherapy beam into the patient's body, the dose deposition pattern of the beam exhibits a columnar or conical distribution along the direction of beam propagation. Therefore, if the target's position shifts in the beam direction or parallel to the beam direction (i.e., the exit direction), this displacement has minimal impact on the total dose received by the tumor. Conversely, if the target's position shifts perpendicular to the beam direction (i.e., the BeamView plane), the target area will deviate from the effective irradiation field of the beam, potentially leading to severe underdose at the target's edge while excessive dose to surrounding normal tissues.

[0059] Additionally, the second coordinate axis can be parallel to the head-to-toe extension direction of the target object, which typically refers to a patient receiving radiation therapy. The head-to-toe extension direction corresponds to the head-to-toe direction in medical anatomy. In many medical linear accelerators or rotating gamma knife radiosurgery devices, the gantry's rotation axis is usually parallel to the length of the treatment bed, that is, parallel to the head-to-toe extension direction when the patient is lying down. (Reference) Figure 1 That is, the first coordinate axis is parallel to the Y-axis.

[0060] Although any two perpendicular coordinates can be defined as the first and second coordinate axes within the BeamView plane, this method of determining coordinate axes is out of sync with the patient anatomical reference system commonly used in clinical practice, increasing the complexity of treatment decisions and the risk of misjudgment.

[0061] Because the plane of rotation of the radiotherapy gantry is typically perpendicular to the head-to-toe extension direction when it rotates around its isocenter, this means that regardless of the gantry's rotation angle, the direction of the treatment beam always varies within a plane perpendicular to this direction. Therefore, the first coordinate axis in the servo coordinate system, perpendicular to the beam direction, maintains a stable spatial orientation that coincides with or is parallel to the head-to-toe extension direction of the human body throughout the gantry rotation. This allows one axis in the servo coordinate system to directly isolate the patient's longitudinal (head-to-toe) positional changes, providing clinicians or radiotherapy engineers with a direct view consistent with traditional human anatomy when observing the tumor motion field.

[0062] like Figure 4As shown, a follow-up coordinate system is established based on the beam emission direction. The beam emission direction 401 of the treatment beam emitted by the treatment head 105 is indicated by a dashed arrow. The plane perpendicular to the beam emission direction 401 is the BeamView plane 402. Within the BeamView plane 402, with the isocenter 403 as the origin, the first coordinate axis corresponds to BV_X, and the second coordinate axis corresponds to BV_Y, forming a follow-up coordinate system. As the gantry 102 rotates, the treatment head 105 moves from... Figure 4 When the position in the left diagram is rotated to the position in the right diagram, the beam output direction 401 also changes accordingly. Consequently, the BV_X and BV_Y follow-up coordinate systems also change accordingly.

[0063] In step S303, the two-dimensional offset of the target on the first coordinate axis and the second coordinate axis is determined.

[0064] The target refers to tumor tissue (e.g., the target area) or implanted gold markers within the patient's body that require location monitoring. Two-dimensional offset refers to the target's positional deviation along two axes in the plane perpendicular to the beam output direction within the servo coordinate system.

[0065] In practical implementation, determining the two-dimensional offset of the target on the first and second coordinate axes can be based on the three-dimensional offset in a fixed coordinate system conforming to the IEC 61217 standard, and then obtaining the corresponding two-dimensional offset through coordinate transformation; alternatively, it can be based on one or more projected images acquired by the imaging device, combined with the geometric calibration relationship between the imaging device and the treatment beam, to determine the two-dimensional offset. Thus, the radiotherapy equipment can be controlled based on the two-dimensional offset.

[0066] For example, when the offset vector calculated based on the two-dimensional offset is within a preset position deviation range, the current position is determined to be within the allowable deviation range, and the normal output of the radiotherapy beam is maintained. In some embodiments, the preset position deviation range can be set according to the tumor location, treatment technology type, and clinical prescription requirements. For example, it can be set to ±1mm for head and neck tumors, ±2mm for body tumors, and ±0.5mm for stereotactic radiotherapy. Alternatively, independent position deviation ranges can be preset for the first and second coordinate axes of the servo coordinate system to adapt to differences in dose sensitivity in different directions. When the offset vector calculated based on the two-dimensional offset exceeds the preset position deviation range, a control signal for the radiotherapy equipment is triggered. This control signal is used to perform at least one of the following operations: immediately stop the radiotherapy beam output and trigger an audible and visual alarm signal; send a position correction command to the patient treatment bed control system, automatically adjust the position of the patient treatment bed in the corresponding direction according to the calculated two-dimensional offset, and automatically resume the radiotherapy beam output after the position correction is completed and the deviation returns to the allowable range; send an online adaptive adjustment command to the treatment planning system, adjust the irradiation field shape and dose distribution of the subsequent beam in real time according to the current actual position deviation, and ensure the target area dose coverage accuracy without interrupting treatment; record the current position deviation data, trigger time, and corresponding gantry angle information, and generate a treatment quality control report for subsequent treatment effect evaluation and system error analysis, etc.

[0067] This embodiment of the invention constructs a dynamic coordinate system that updates in real time with the current treatment beam's exit direction. The plane defined by this dynamic coordinate system is strictly perpendicular to the exit direction, eliminating the interference of offset components along the exit direction on treatment control decisions. Only the two-dimensional offset within the BeamView plane, which truly affects the dose distribution, is used as the control basis for the radiotherapy equipment. This avoids unnecessary treatment interruptions or patient position corrections triggered by deviations along the exit direction that have no actual therapeutic significance. Furthermore, it solves the problem of small overall error values ​​but large actual dose-affected offsets within the BeamView plane under a fixed coordinate system, significantly improving the treatment efficiency and patient experience of radiotherapy while ensuring treatment accuracy.

[0068] It is understandable that, in order to further clarify the spatial geometric definition of the treatment beam, in some specific implementations, the beam emission direction is specifically the direction of the central axis of the treatment beam emitted by the treatment head of the radiotherapy device, and the central axis of the treatment beam passes through the origin.

[0069] Since the therapeutic beam (especially the irregular beam adjusted by the multi-leaf collimator) may have a certain divergence angle, its geometric central axis is used as the beam exit direction.

[0070] The dose distribution of the therapeutic beam is axially symmetric, with the axis of symmetry being the central axis of the therapeutic beam (i.e., the beam center). In a plane perpendicular to this central axis, the dose distribution exhibits a concentric circular pattern centered on the central axis. Target displacement within this plane directly leads to a shift in the dose distribution within the target area, affecting the treatment effect. The dose distribution along the central axis changes more gradually, and target displacement in this direction has a smaller impact on target area dose coverage. The central axis of the therapeutic beam passes through the origin (isocentricity), ensuring that therapeutic beams incident from different angles converge to the same spatial point. This makes the origin of the servo coordinate system coincide with the center of symmetry of the dose distribution, ensuring the physical accuracy of positional deviation calculations.

[0071] like Figure 5 The diagram shown illustrates the determination of the beam direction. The therapeutic beam generated by the treatment head 105 is represented by a dashed line. The beam direction 401 is the direction of the line connecting the focal point of the treatment head 105 and the isocenter, i.e., the direction of the central axis of the therapeutic beam.

[0072] Furthermore, the beam exit direction can be determined based on the geometric center of the target area. The geometric center of the target area is its three-dimensional geometric center point. Connecting the focal point of the treatment head's radiation source to the geometric center of the target area yields the beam exit direction pointing towards the center of the target area. In actual radiotherapy, due to positioning errors, organ movement, or tumor regression, the geometric center of the target area may not coincide with the isocenter of the radiotherapy equipment. In this case, the actual target of the treatment beam is the target area, not the isocenter, and the direction pointing towards the center of the target area better represents the actual direction of the treatment beam. Using the geometric center of the target area to determine the beam exit direction ensures that the plane of the servo coordinate system remains consistent with the actual irradiated plane of the target area, ensuring that the positional deviation assessment targets the offset of the target area itself.

[0073] It should be noted that the geometric center axis direction of the treatment beam and the direction pointing to the geometric center of the target area mentioned in the above embodiments are merely exemplary implementations and are not intended to limit the scope of protection of this disclosure. In other embodiments, the beam exit direction can also be determined based on various methods such as the penumbra center of the treatment beam, the direction of maximum dose gradient, the center of the clinical target area, the center of the planning target area, the location of the maximum dose point of the tumor, and the effective center of the beam. Regardless of the specific method used to define the beam exit direction, as long as the follower coordinate system constructed based on the beam exit direction can exclude offset components that have no significant impact on the dose distribution and retain only the in-plane offset that can truly reflect the dose effect of the treatment beam, and control the radiotherapy equipment based on the two-dimensional offset, it falls within the scope of protection of this disclosure.

[0074] Understandably, in order to form a complete orthogonal reference system in three-dimensional space to facilitate subsequent possible spatial matrix projection calculations, in some implementations, in addition to the first and second coordinate axes, the servo coordinate system is configured to include a third coordinate axis, which is the central axis of the therapeutic beam. The three coordinate axes of the servo coordinate system are mutually perpendicular, and the dot product of any two coordinate axes is zero.

[0075] Combination Figure 4 ,like Figure 6 The diagram shows a moving coordinate system including a third coordinate axis. The first coordinate axis (BV_X axis in the diagram), the second coordinate axis (BV_Y axis in the diagram), and the third coordinate axis (BV_Z axis in the diagram) together form a right-handed orthogonal coordinate system, namely the BeamView coordinate system.

[0076] Although the servo coordinate system constructs a three-dimensional space including the third coordinate axis, the final control decision-making step relies only on the two-dimensional offsets on the first and second coordinate axes. The offset in the direction of the third coordinate axis (i.e., the central axis of the treatment beam) can be calculated, but it is not used as the control basis for triggering the radiotherapy device.

[0077] Furthermore, traditional radiotherapy equipment uses a fixed coordinate system conforming to the IEC 61217 standard as a unified position reference. Position data from all intraoperative image guidance systems, treatment planning systems, and equipment control systems are output and stored within this fixed coordinate system. The method for calculating three-dimensional offsets based on a fixed coordinate system is very mature, and various radiotherapy devices have built-in, comprehensive three-dimensional position deviation calculation modules capable of stably outputting high-precision three-dimensional offset data.

[0078] Therefore, in some embodiments, the existing 3D offset calculation results of existing equipment can be directly reused without developing new imaging and position calculation algorithms. The 2D offset in the following coordinate system can be obtained simply through a coordinate transformation step. This implementation method maximizes the utilization of existing equipment's hardware and software resources, reducing technical modification costs and implementation difficulty. Specifically, such as... Figure 7 As shown, in step S303 above, determining the two-dimensional offset of the target on the first coordinate axis and the second coordinate axis includes the following steps S304 and S305.

[0079] In step S304, the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy equipment is obtained.

[0080] A fixed coordinate system refers to a fixed reference coordinate system within the radiotherapy equipment room. In practice, a fixed coordinate system conforming to the IEC 61217 standard is typically used. In this fixed coordinate system, the X-axis represents the left-right direction of the object, used to characterize the patient's lateral displacement on the treatment bed; the Y-axis represents the head-to-toe extension direction of the object, usually parallel to the longitudinal translation axis of the treatment bed and the rotation axis of the gantry; the Z-axis represents the front-back direction of the object, used to characterize the patient's positional changes in vertical height or ventral-dorsal direction. The origin coincides with the isocenter of the radiotherapy equipment. Three-dimensional offset refers to the difference in the target's three-dimensional spatial position relative to its pre-treatment reference position in the fixed coordinate system, including offsets in the X, Y, and Z directions.

[0081] In step S305, the three-dimensional offset is transformed from the fixed coordinate system to the moving coordinate system to obtain the two-dimensional offset.

[0082] When the image guidance system within the radiotherapy equipment dynamically captures images of the target during the procedure and registers them with reference images generated from the radiotherapy plan, the calculated real-time positional deviation of the target in this fixed coordinate system is a three-dimensional offset containing three-dimensional spatial components. However, since this fixed coordinate system cannot sense the real-time rotation of the gantry, the values ​​of its various axes cannot directly reflect the physical relative position of the target with respect to the current treatment beam.

[0083] Therefore, the electronic device can be configured to execute a coordinate system transformation algorithm, which takes the three-dimensional offset obtained in the fixed coordinate system as input, and dynamically transforms the three-dimensional offset to the following coordinate system through spatial rotation transformation and projection matrix mapping, thereby extracting the two-dimensional offset located in the plane formed by the first coordinate axis and the second coordinate axis.

[0084] This transformation process is not a simple reduction of dimensions, but rather a reconstruction based on the physical dose field. To ensure that the spatial coordinate transformation process meets the accuracy and timeliness requirements of real-time radiotherapy, this disclosure provides a specific mathematical analytical implementation.

[0085] In some implementations, based on the beam output direction, the first and second direction vectors corresponding to the first and second coordinate axes in the moving coordinate system are determined in the fixed coordinate system; the dot product of the three-dimensional offset and the first direction vector is determined as the first component value of the two-dimensional offset on the first coordinate axis; the dot product of the three-dimensional offset and the second direction vector is determined as the second component value of the two-dimensional offset on the second coordinate axis; or, the offset of the three-dimensional offset corresponding to the Y-axis in the fixed coordinate system is determined as the second component value of the two-dimensional offset on the second coordinate axis.

[0086] It can be envisioned that when the gantry rotates to a specific angle, the output direction of the current treatment beam has a definite direction cosine expression in the fixed coordinate system. Since the servo coordinate system and the fixed coordinate system share the same radiotherapy isocenter as the origin, the spatial orientation of each coordinate axis in the servo coordinate system can be represented by a unit vector. Specifically, the first direction vector is the unit vector of the first coordinate axis of the servo coordinate system, represented in the fixed coordinate system, and the second direction vector is the unit vector of the second coordinate axis of the servo coordinate system, represented in the fixed coordinate system. These direction vectors can be calculated in real time using trigonometric functions based on the real-time rotation angle of the gantry and the fixed geometric parameter matrix of the equipment.

[0087] At the geometric level, once the three-dimensional offset of the target in the fixed coordinate system is obtained (which can be considered as a spatial displacement vector pointing from the isocenter to the target's current actual position), the projection length of this spatial displacement vector along a specified axis in the moving coordinate system can be determined through a dot product operation. By taking the dot product of the spatial displacement vector with the first direction vector, the projection component of the displacement on the first coordinate axis, i.e., the first component value, can be extracted. Similarly, by taking the dot product of the spatial displacement vector with the second direction vector, its projection component on the second coordinate axis, i.e., the second component value, can be obtained.

[0088] Understandably, since the dot product operation only involves basic multiplication and addition at the computer level and does not involve complex transcendental function iteration, this vector dot product can be configured to run in the parallel processor of electronic devices, so that coordinate transformation can be completed in a short time, meeting the real-time requirements of dynamic tracking during intraoperative radiotherapy.

[0089] Understandably, the specific beam direction can be determined based on the angle between the current treatment beam's beam direction and the imaging optical axis of the imaging device, as well as the gantry rotation angle.

[0090] In actual hardware configurations, the imaging device and treatment head are typically rigidly mounted on a rack. The central axis (beam direction) of the treatment beam emitted by the treatment head and the central axis (imaging optical axis) of the treatment beam emitted by the imaging device intersect at an isocenter in space. A constant spatial geometric angle (e.g., 30 degrees, 45 degrees, or 90 degrees) exists between these two optical axes, precisely measured at the factory or during calibration. Therefore, the angle between the current beam direction of the treatment beam and the imaging optical axis of the imaging device can be directly obtained.

[0091] During the rotation of the gantry, the beam direction and the imaging optical axis are always coplanar with the gantry rotation plane (XOZ plane), and the Y-direction component is always 0.

[0092] The specific formula derivation process for determining the beam output direction and obtaining the first component value on the first coordinate axis and the second component value on the second coordinate axis in the servo coordinate system by three-dimensional offset transformation is as follows: First, determine the unit vector of the treatment beam's output direction. In a fixed coordinate system, the gantry rotates around the Y-axis (head-to-toe direction) of the fixed coordinate system, with the rotation plane being the XOZ plane. Let the gantry rotation angle be θ. When the gantry is at 0°, the optical axis of the treatment beam (i.e., the current output direction of the treatment beam) is along the +Z-axis of the fixed coordinate system. A positive angle represents rotation from the +Z-axis to the +X-axis. Therefore, the unit vector of the treatment beam's output direction can be expressed as: .

[0093] Because the imaging device and the treatment head are rigidly connected to the rotating frame, their relative positions remain unchanged, and a fixed geometric angle exists between the treatment beam optical axis and the imaging optical axis. This included angle is the factory calibration value and does not change with rig rotation. Therefore, the unit vector of the imaging optical axis direction can be derived based on the included angle between the beam direction and the fixed angle: .

[0094] Next, a moving coordinate system is constructed, and the unit direction vectors of its coordinate axes are determined. The moving coordinate system shares the isocenter of the radiotherapy equipment as its origin with the fixed coordinate system. The third coordinate axis is along the direction of the treatment beam exit, i.e., the unit vector of the exit direction is the same as the aforementioned beam exit direction. The coordinate axes coincide; the second coordinate axis is aligned with the Y-axis of the fixed coordinate system, corresponding to the head-to-foot direction; the first coordinate axis is determined by the right-hand rule and obtained by the cross product of the second and third coordinate axes. Based on this, the unit direction vectors of the first and second coordinate axes in the moving coordinate system and in the fixed coordinate system can be derived. The first direction vector (first coordinate axis) is: Second direction vector (second coordinate axis): .

[0095] Finally, the conversion from 3D offset to 2D offset is completed using vector dot product. Let the 3D offset of the target in a fixed coordinate system be: According to the principle of vector projection, the projection length of a 3D offset onto a certain coordinate axis is equal to the dot product of the 3D offset and the unit direction vector of that coordinate axis. Therefore, the first component value (first coordinate axis component): Second component value (second coordinate axis component): .

[0096] In a standard rack rotation scenario, since the Y-axis of the fixed coordinate system is configured to be parallel to the rack rotation axis, and the follower coordinate system rotates synchronously with the rack, the Y-axis (head and foot extension direction) of the fixed coordinate system and the second coordinate axis in the follower coordinate system remain parallel or equivalent in spatial geometry during the dynamic process of rack rotation.

[0097] Therefore, under this spatial orthogonal alignment, the target's offset on the Y-axis of the fixed coordinate system is numerically and spatially equivalent to its second component value on the second coordinate axis of the moving coordinate system. Thus, the dot product operation on the second coordinate axis can be omitted; the offset on the Y-axis of the fixed coordinate system can be directly assigned to the second component value of the second coordinate axis in the moving coordinate system. This method, by utilizing parallelism, simplifies the matrix projection calculation in one dimension without sacrificing accuracy, further improving real-time performance.

[0098] It is understood that the three-dimensional offset in the fixed coordinate system is determined based on the projected images obtained under various imaging methods. Specific imaging methods may include at least one of kilovolt-level projection imaging, infrared imaging, body surface imaging, ultrasound imaging, MRI imaging, or computed tomography imaging. Regardless of the imaging method from which the three-dimensional offset originates, the electronic device disclosed herein can be configured to project the image onto a two-dimensional action plane perpendicular to the beam output direction through coordinate transformation. Therefore, this disclosure does not specifically limit the specific imaging method.

[0099] Because a single 2D projection image is an orthogonal or perspective projection of a 3D object onto the imaging plane, it loses depth information along the imaging optical axis, causing targets at different depths to have the exact same projected position on the image. Therefore, in general scenarios without any prior information, the 3D offset of a target needs to be accurately determined based on at least two projection images obtained from non-collinear angles, using triangulation principles for 3D reconstruction.

[0100] However, in certain specific cases, the three-dimensional offset can be accurately determined based on a single projected image. Specifically, when the target's offset vector is parallel to the first direction of the imaging device's detector, the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device is determined based on a single projected image, where the first direction is perpendicular to the radial direction of the radiotherapy device, such as... Figure 8 The KV_X direction is shown.

[0101] The detector rotates with the frame, and its imaging plane is perpendicular to the imaging optical axis. The radial direction of the radiotherapy equipment refers to the geometric axis pointing from the focal point of the imaging X-ray source to the isocenter of the radiotherapy. The first direction on the detector refers to the specific pixel arrangement direction that is perpendicular to the aforementioned radial direction in three-dimensional space within the coordinate system of the flat panel detector. The offset vector refers to the three-dimensional offset with direction.

[0102] This can be understood as the target's offset vector being parallel to the first direction of the imaging device's detector, indicating that the target's actual direction of motion in three-dimensional space is strictly parallel to the transverse scan line on the detector.

[0103] Specifically, such as Figure 8 The diagram illustrates the principle of determining a two-dimensional offset based on a single projected image. The dashed lines represent the fixed coordinate system X and Z, the solid lines represent the moving coordinate system BV_X and BV_Z, and the solid lines represent the coordinate system KV_X and KV_Y of detector 104. The isocenter is O. The isocenter corresponds to O' in the projected image formed by detector 104, and the target P corresponds to P' in the projected image formed by detector 104. The source-axis distance SAD refers to the distance from the X-ray tube 103 to the isocenter, and the source-image distance SID refers to the distance from the X-ray tube 103 to the isocenter.

[0104] The detector's first direction (the lateral direction, i.e., the direction where the projection offset O'P' is located) is perpendicular to the imaging optical axis and lies within the gantry rotation plane. Its unit vector is obtained by cross-multiplying the imaging optical axis unit vector by the head-to-feet direction unit vector. When the target's offset vector (OP) is parallel to the detector's first direction (KV_X), the direction of the three-dimensional offset is... Completely identical, therefore Transform to the moving coordinate system: Similarly, .

[0105] Combination Figure 8 In the right figure, when the offset vector OP is parallel to KV_X, it effectively limits the target's three-dimensional offset to exist only in a plane perpendicular to the imaging optical axis (imaging center axis), and the offset component along the KV_Y axis is zero. Under this specific constraint, the depth offset component of the target along the imaging optical axis is zero, eliminating the inherent ambiguity of losing depth information in a single projection image. The O'P' vector measured in the projection image uniquely corresponds to the OP vector in the plane perpendicular to the imaging optical axis in physical space, eliminating the need for additional projection images for triangulation reconstruction. By using the pre-calibrated angular relationship between the imaging optical axis and the beam output direction, the OP vector can be accurately decomposed into two orthogonal components in the follower coordinate system, thus accurately determining the two-dimensional offset required for treatment control using only a single projection image.

[0106] This single-image-based solution method does not require waiting for the gantry to rotate to the next orthogonal angle, nor does it require two imaging devices to capture images simultaneously. It can instantly capture the complete three-dimensional spatial deviation with just a single pulse exposure, thereby further reducing the computational delay of image guidance.

[0107] Furthermore, when there is only one projected image and the offset vector OP is not parallel to KV_X, the target may simultaneously have a lateral offset perpendicular to the imaging optical axis and a depth offset along the imaging optical axis. The single projected image loses depth information. In this case, it is impossible to uniquely determine the target's true three-dimensional spatial offset through a single projected image. However, based on the angle between the KV optical axis (the imaging optical axis of the imaging device) and the treatment beam optical axis (the beam output direction), the trend reference component of the target in the lateral direction (first coordinate axis) of the follower coordinate system can still be obtained through a single projected image to help determine the target's offset direction or offset state.

[0108] Specifically, the lateral projection offset O'P' measured on the detector is first converted to the isocenter plane according to the central projection geometry, thus obtaining the equivalent offset vector on the isocenter plane. The offset vector OP corresponds to the spatial projection length of the target in the first direction of the detector, and it satisfies the following with its two orthogonal components in the following coordinate system: Because there are two unknown components, it is not possible to uniquely solve the problem based on a single projection image. and The true value.

[0109] However, the trend reference component of the target in the BV_X direction of the moving coordinate system can be derived: This trend reference component characterizes the maximum possible offset and offset trend of the target in the dose-sensitive lateral direction. When the depth offset component of the target along the imaging optical axis is zero, this trend reference component is equal to the true lateral offset; when depth offset exists, this trend reference component can still reflect the approximate range and direction of the lateral offset.

[0110] This trend reference component can be used for early warning of deviation risk during radiotherapy. When the target is within the preset safety range, it can be considered that there is no significant risk of deviation in the lateral direction, and treatment can proceed normally; when When the target is outside the safe range, it indicates that there may be a large lateral deviation.

[0111] Corresponding to the above-described embodiments of the real-time target tracking and control method, this specification also provides embodiments of a real-time target tracking and control device. Figure 9 This is a schematic diagram illustrating the composition of the real-time target tracking and control device provided in this disclosure. The electronic device may internally include a real-time target tracking and control device 900 composed of multiple functional modules (logically or physically), which can be implemented through software programming. For example... Figure 9 As shown, the real-time target tracking and control device 900 includes: an acquisition section 901, a construction section 902, and a determination section 903; Acquisition part 901 is configured to acquire the current treatment beam's output direction; The construction part 902 is configured to construct a follow-up coordinate system based on the beam direction, which changes with the beam angle. The follow-up coordinate system takes the isocenter of the radiotherapy device as the origin and includes at least a first coordinate axis and a second coordinate axis that are perpendicular to each other. The beam direction is perpendicular to the plane formed by the first coordinate axis and the second coordinate axis. The determination part 903 is configured to determine the two-dimensional offset of the target on the first and second coordinate axes in order to control the radiotherapy device based on the two-dimensional offset.

[0112] In some embodiments, the beam direction is the direction of the central axis of the treatment beam emitted by the treatment head of the radiotherapy device, and the central axis of the treatment beam passes through the origin.

[0113] In some embodiments, the second coordinate axis is parallel to the head and toe extension direction of the object containing the target.

[0114] In some embodiments, the determining part 903 is configured to obtain the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device, wherein the X-axis is the left-right direction of the object, the Y-axis is the head-to-feet extension direction of the object, and the Z-axis is the front-back direction of the object; and the three-dimensional offset is transformed from the fixed coordinate system to the following coordinate system to obtain the two-dimensional offset.

[0115] In some embodiments, the determining portion 903 is configured to, based on the beam output direction, determine the first direction vector and the second direction vector corresponding to the first coordinate axis and the second coordinate axis in the fixed coordinate system in the moving coordinate system; determine the dot product of the three-dimensional offset and the first direction vector as the first component value of the two-dimensional offset on the first coordinate axis; determine the dot product of the three-dimensional offset and the second direction vector as the second component value of the two-dimensional offset on the second coordinate axis; or, determine the offset of the three-dimensional offset corresponding to the Y-axis in the fixed coordinate system as the second component value of the two-dimensional offset on the second coordinate axis.

[0116] In some embodiments, the imaging methods for obtaining the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device include at least one of kilovolt-level projection imaging, infrared imaging, body surface imaging, ultrasound imaging, magnetic resonance imaging, or computed tomography imaging.

[0117] In some embodiments, the determining portion 903 is configured to acquire a single projected image of the target; when the target's offset vector is parallel to a first direction of the detector of the imaging device, the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device is determined based on the single projected image, the first direction being perpendicular to the radial direction of the radiotherapy device.

[0118] In some embodiments, the acquisition portion 901 is configured to, when the offset vector of the target is not parallel to the first direction of the detector of the imaging device, acquire a trend reference component of the target on the first coordinate axis of the servo coordinate system based on the angle between the output direction of the current treatment beam and the imaging optical axis of the imaging device through a single projected image. The trend reference component is used to assist in determining the offset direction of the target.

[0119] In some embodiments, the acquisition portion 901 is configured to acquire the current treatment beam's output direction based on the angle between the current treatment beam's output direction and the imaging optical axis of the imaging device, as well as the gantry rotation angle.

[0120] The real-time target tracking control device of this disclosure is used to implement the corresponding real-time target tracking control method in the foregoing embodiments, and has the beneficial effects of the corresponding method embodiments, which will not be repeated here. Furthermore, the functional implementation of each part in the real-time target tracking control device of this disclosure can be referred to the description of the corresponding part in the foregoing method embodiments, which will also not be repeated here.

[0121] This disclosure also provides a computer-readable storage medium storing at least one instruction that is executed by a processor to implement the target real-time tracking and control method as described in the above embodiments.

[0122] It is understood that the computer-readable storage medium can be a non-transitory computer-readable storage medium, such as an optical disc, portable hard drive, USB flash drive, magnetic tape, or any form of solid-state storage device. The medium contains compiled and optimized machine-executable code. When this code is imported into and executed by the processor of an existing radiotherapy control device in a hospital, no costly hardware modifications to the large mechanical structures of the radiotherapy device (such as collimators, gantry spindles, etc.) are required. The traditional position monitoring software system based on a fixed reference system can be seamlessly upgraded to the dynamic follow-up tracking control system based on the physical dose field surface provided in this disclosure simply through a software upgrade. This has extremely high application and promotional value for improving the treatment safety and beam continuity of existing clinical radiotherapy equipment.

[0123] When the integrated processing unit described above is implemented as a software functional unit and sold or used as an independent product, it is understood that the division of each module is only a logical functional division, and there may be other division methods in actual physical implementation. For example, multiple units or components can be combined or integrated into another microcontroller system. The technical solutions of this disclosure, in essence or in terms of contributing to the prior art, can be fully or partially embodied in the form of software products, and the aforementioned storage medium includes various media capable of storing program code. Those skilled in the art should realize that the functions described in this disclosure can be implemented using hardware, software, firmware, or any combination thereof, and, without conflict, the technical solutions described in the above embodiments can be arbitrarily combined. The above descriptions are only specific embodiments of this disclosure, but the protection scope of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the protection scope of this disclosure. It should be noted that the technical solutions described in this disclosure can be arbitrarily combined without conflict.

[0124] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A real-time target tracking and control method, characterized in that, The method includes: Obtain the current direction of the treatment beam; Based on the beam output direction, a follow-up coordinate system that changes with the beam angle is constructed. The follow-up coordinate system takes the isocenter of the radiotherapy device as the origin and includes at least a first coordinate axis and a second coordinate axis that are perpendicular to each other. The beam output direction is perpendicular to the plane formed by the first coordinate axis and the second coordinate axis. Determine the two-dimensional offset of the target on the first and second coordinate axes, and control the radiotherapy device based on the two-dimensional offset.

2. The method according to claim 1, characterized in that, The beam emission direction is the direction of the central axis of the therapeutic beam emitted by the treatment head of the radiotherapy device, and the central axis of the therapeutic beam passes through the origin.

3. The method according to claim 1, characterized in that, The second coordinate axis is parallel to the head and feet extension direction of the object where the target is located.

4. The method according to any one of claims 1 to 3, characterized in that, Determining the two-dimensional offset of the target on the first coordinate axis and the second coordinate axis includes: The three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device is obtained, wherein the X-axis is the left-right direction of the object, the Y-axis is the head-to-toe extension direction of the object, and the Z-axis is the front-back direction of the object; The three-dimensional offset is transformed from the fixed coordinate system to the moving coordinate system to obtain the two-dimensional offset.

5. The method according to claim 4, characterized in that, The step of transforming the three-dimensional offset from the fixed coordinate system to the moving coordinate system to obtain the two-dimensional offset includes: Based on the beam output direction, determine the first direction vector and the second direction vector corresponding to the first coordinate axis and the second coordinate axis in the servo coordinate system in the fixed coordinate system; The dot product of the three-dimensional offset and the first direction vector is determined as the first component value of the two-dimensional offset on the first coordinate axis. The dot product of the three-dimensional offset and the second direction vector is determined as the second component value of the two-dimensional offset on the second coordinate axis; or, the offset of the three-dimensional offset in the fixed coordinate system corresponding to the Y-axis is determined as the second component value of the two-dimensional offset on the second coordinate axis.

6. The method according to claim 4, characterized in that, The imaging method for obtaining the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device includes: At least one of kilovolt-level projection imaging, infrared imaging, body surface imaging, ultrasound imaging, nuclear magnetic resonance imaging, or computed tomography imaging.

7. The method according to claim 4, characterized in that, The step of obtaining the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device includes: Acquire a single projected image of the target; When the target's offset vector is parallel to the first direction of the detector of the imaging device, the three-dimensional offset of the target in the fixed coordinate system of the radiotherapy device is determined based on the single projected image, wherein the first direction is perpendicular to the radial direction of the radiotherapy device.

8. The method according to claim 7, characterized in that, The method further includes: When the offset vector of the target is not parallel to the first direction, based on the angle between the output direction of the current treatment beam and the imaging optical axis of the imaging device, the trend reference component of the target on the first coordinate axis of the servo coordinate system is obtained through the single projection image. The trend reference component is used to assist in determining the offset direction of the target.

9. The method according to claim 1, characterized in that, Obtain the current treatment beam's exit direction, including: The current treatment beam's output direction is obtained based on the angle between the current treatment beam's output direction and the imaging optical axis of the imaging device, as well as the gantry rotation angle.

10. An electronic device, characterized in that, It includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the real-time target tracking control as described in any one of claims 1 to 9.

Images