System and method for dynamic multi-blade collimator tracking

Abstract

The present disclosure provides systems and methods for dynamic multi-blade collimator tracking. The system includes at least one storage device and at least one processor in communication with the at least one storage device, the at least one processor being directed to cause the system to perform a method including: identifying a plurality of working blades of a multi-blade collimator at a control point; and determining a sampling rate of the electron radiation field imaging device at the control point based on the planned velocity profile of each of the plurality of working blades.

Description

Description of the case

[0001] This application is a divisional application filed for a Chinese application with a filing date of August 21, 2020, application number 202080103366.5, and invention name “System and method for dynamic multi-leaf collimator tracking”. Technical Field

[0002] The present application relates generally to radiation technology and, more particularly, to systems and methods for dynamic multi-leaf collimator tracking in radiation. Background Art

[0003] Radiation is widely used for imaging and treatment, such as cancer treatment and several other health conditions. Multi-leaf collimators play an important role in dynamic conformal radiation therapy. The motion accuracy of the multi-leaf collimator is required to ensure the effectiveness of radiation therapy, especially for stereotactic radiosurgery (SRS), stereotactic body radiation therapy (SBRT), etc. Therefore, it may be desirable to provide systems and methods for dynamic multi-leaf collimator tracking. Summary of the invention

[0004] According to one aspect of the present disclosure, a system for dynamic multi-leaf collimator tracking is provided. The system may include at least one storage device, the at least one storage device including a set of instructions for dynamic multi-leaf collimator tracking, and at least one processor communicating with the at least one storage device. When executing the set of instructions, the at least one processor is directed to cause the system to perform the following operations. Identify multiple working blades of a multi-leaf collimator at a control point; determine a signal acquisition area of ​​an electronic portal imaging device for the control point based on multiple planned position trajectories of the multiple working blades, wherein the signal acquisition area is a part of an imaging plane of the electronic portal imaging device, and the signal acquisition area includes multiple acquisition rows; acquire an image from the electronic portal imaging device at the control point, wherein the image includes information acquired in the signal acquisition area.

[0005] In some embodiments, the operation further includes determining a sampling rate of the electronic portal imaging device at the control point based on a planned speed profile of each of the plurality of working blades, wherein the electronic portal imaging device captures the image using the sampling rate at the control point.

[0006] In some embodiments, determining the signal acquisition area of ​​the electronic portal imaging device for the control point includes: acquiring blade information of the multiple working blades based on the planned position trajectory of each of the multiple working blades; and determining the starting acquisition row and the ending acquisition row of the multiple acquisition rows based on the blade information of the multiple working blades and the electronic portal imaging device information of the electronic portal imaging device.

[0007] In some embodiments, the blade information of the multiple working blades includes starting working blade information, ending working blade information, position information of the center blade of the multi-leaf collimator, and projection width of the blade onto the isocenter plane of the multi-leaf collimator.

[0008] In some embodiments, the electronic portal imaging device information of the electronic portal imaging device includes the pixel size of the electronic portal imaging device, the image size captured by the electronic portal imaging device, the source image distance, and the offset value of the center of the electronic portal imaging device relative to the central axis of the light beam at the control point.

[0009] In some embodiments, determining the sampling rate of the electronic portal imaging device at the control point includes: obtaining the maximum blade speed of all blades of the multi-leaf collimator; obtaining the maximum sampling rate of the electronic portal imaging device; based on the planned speed curve of each working blade among the multiple working blades, obtaining the maximum working blade speed of the working blades among the multiple working blades at the control point; and determining the sampling rate of the electronic portal imaging device at the control point based on the maximum blade speed, the maximum sampling rate of the electronic portal imaging device and the maximum working blade speed at the control point.

[0010] In some embodiments, the plurality of planned position trajectories of the plurality of working blades are determined based on a treatment plan.

[0011] In some embodiments, the plurality of planned velocity profiles for the plurality of working blades are determined based on a treatment plan.

[0012] In some embodiments, the operation also includes: acquiring multiple images, each of the multiple images corresponding to data collected by the electronic portal imaging device using a sampling rate of one control point among multiple control points in the signal acquisition area; and for each of the multiple working blades, determining a measured position trajectory and a measured velocity curve of each working blade based on the multiple images; determining a position trajectory error of each working blade based on the planned position trajectory and the measured position trajectory of each working blade; and determining a velocity curve error of each working blade based on the planned velocity curve and the measured velocity curve of each working blade.

[0013] In some embodiments, determining the measurement position trajectory and the measurement speed curve of each working blade based on the multiple images includes: obtaining multiple corrected images by correcting the multiple images based on an image correction algorithm; and determining the measurement position trajectory and the measurement speed curve of each working blade based on the multiple corrected images.

[0014] In some embodiments, determining the measurement position trajectory and the measurement speed curve of each working blade based on the multiple correction images includes: for each working blade among the multiple working blades, obtaining the pixel position of each working blade in each correction image among the multiple correction images; determining the field position corresponding to each pixel position based on a predetermined mapping relationship between the pixel position and the field position; and acquiring the measurement position trajectory and the measurement speed curve of each working blade based on the field position corresponding to each pixel position and a time synchronization signal, wherein the time synchronization signal is configured to synchronize a first measurement time of the measurement position trajectory with a first planned time of the planned position trajectory, and synchronize a second measurement time of the measurement speed curve with a second planned time of the planned speed curve.

[0015] According to one aspect of the present disclosure, a method for dynamic multi-leaf collimator tracking is provided. The method may include identifying multiple working leaves of a multi-leaf collimator at a control point; determining a signal acquisition area of ​​an electronic portal imaging device for the control point based on multiple planned position trajectories of the multiple working leaves, wherein the signal acquisition area is a part of an imaging plane of the electronic portal imaging device, and the signal acquisition area includes multiple acquisition rows; and acquiring an image from the electronic portal imaging device at the control point, wherein the image includes information acquired in the signal acquisition area.

[0016] In some embodiments, according to one aspect of the present disclosure, a non-transitory readable medium is provided. The non-transitory readable medium includes at least one storage device, and the at least one storage device includes a set of instructions for dynamic multi-leaf collimator tracking. When executed by at least one processor of an electrical device, the at least one set of instructions instructs the at least one processor to execute a method, the method comprising: identifying multiple working leaves of a multi-leaf collimator at a control point; determining a signal acquisition area of ​​an electronic portal imaging device for the control point based on multiple planned position trajectories of the multiple working leaves, wherein the signal acquisition area is a part of an imaging plane of the electronic portal imaging device, and the signal acquisition area includes multiple acquisition rows; acquiring an image from the electronic portal imaging device at the control point, wherein the image includes information acquired in the signal acquisition area.

[0017] Additional features will be set forth in part in the following description, and in part will become apparent to those skilled in the art upon examination of the following and accompanying drawings, or may be learned by production or operation of the embodiments. The features of the present disclosure may be realized and obtained by practicing or using various aspects of the methods, means, and combinations set forth in the detailed examples discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present disclosure is further described according to exemplary embodiments. These exemplary embodiments are described in detail with reference to the accompanying drawings. These embodiments are non-limiting exemplary embodiments, in which the same reference numerals represent similar structures throughout the several views of the accompanying drawings, in which:

[0019] Figure 1 is a schematic diagram of an exemplary radiation therapy (RT) system according to some embodiments of the present disclosure;

[0020] Figure 2 is a schematic diagram of hardware and / or software components of an exemplary computing device according to some embodiments of the present disclosure;

[0021] Figure 3 is a schematic diagram of hardware and / or software components of an exemplary mobile device according to some embodiments of the present disclosure;

[0022] Figure 4 is a block diagram of an exemplary processing device according to some embodiments of the present disclosure;

[0023] Figure 5 is a flow chart of an exemplary process for dynamic multi-leaf collimator tracking according to some embodiments of the present disclosure;

[0024] Figure 6 is a schematic diagram of an exemplary signal collection area and an exemplary image according to some embodiments of the present disclosure;

[0025] Figure 7 is a flowchart of an exemplary process for determining a sampling frequency at a control point according to some embodiments of the present disclosure;

[0026] Figure 8 is a flow chart of an exemplary process of determining a position trajectory error and a speed curve error of each working blade according to some embodiments of the present disclosure;

[0027] Fig. 9 is a schematic diagram of an exemplary planned position trajectory and an exemplary measured position trajectory of a working blade according to some embodiments of the present disclosure;

[0028] Fig.10is a schematic diagram of an exemplary position trajectory error of a working blade according to some embodiments of the present disclosure; and

[0029] Fig.11 is a schematic diagram of an exemplary process for obtaining a measurement position trajectory and a measurement velocity curve according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0030] In the detailed description that follows, many specific details are set forth by way of example in order to provide a thorough understanding of the relevant disclosure. However, it will be apparent to those skilled in the art that the present disclosure may be implemented without these details. In other cases, well-known methods, procedures, systems, components, and / or circuits have been described at a relatively high level but without detailed description to avoid unnecessarily obscuring aspects of the present disclosure. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments shown, but is in accordance with the widest scope consistent with the claims.

[0031] The terms used herein are for the purpose of describing specific example embodiments only and are not intended to be limiting. As used herein, the singular forms "a", "an", and "the" may also be intended to include the plural forms, unless the context clearly reflects otherwise. It is further understood that when used in this specification, the terms "comprising", "including" specify the presence of the features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0032] It should be understood that the terms "system", "engine", "unit", "module" and / or "block" used herein are a method of distinguishing different components, elements, parts, sections or components at different levels in ascending order. However, if these terms achieve the same purpose, they can be replaced by another expression.

[0033] Generally, the terms "module," "unit," or "block" as used herein refer to logic embodied in hardware or firmware, or to a collection of software instructions. The modules, units, or blocks described herein may be implemented as software and / or hardware, and may be stored in any type of non-transitory computer-readable medium or other storage device. In some embodiments, software modules / units / blocks may be compiled and linked into an executable program. It should be understood that software modules may be called from other modules / units / blocks or themselves, and / or may be called in response to detected events or interrupts. A program configured to be executed on a computing device (e.g., a processor) may be provided on a computer-readable medium. Figure 2 The software modules / units / blocks executed on a processor 210 shown in the figure, such as a compressed disk, a digital video disk, a flash drive, a disk, or any other tangible medium, or as a digital download (and may be initially stored in a compressed or installable format, requiring installation, decompression or decryption before execution). Such software code may be stored in part or in whole on a storage device of the executing computing device for execution by the computing device. The software instructions may be embedded in firmware, such as an erasable programmable read-only memory (EPROM). It is further understood that hardware modules / units / blocks may be included in connected logical components, such as gates and triggers, and / or may be included in programmable units, such as programmable gate arrays or processors. The modules / units / blocks or computing device functions described herein may be implemented as software modules / units / blocks, but may be represented in hardware or firmware. In general, the modules / units / blocks described herein refer to logical modules / units / blocks that can be combined with other modules / units / blocks or divided into sub-modules / sub-units / sub-blocks, despite their physical organization or storage. This description may apply to a system, an engine, or a portion thereof.

[0034] It should be understood that when a unit, engine, module or block is referred to as being "on," "connected to," or "coupled to" another unit, engine, module or block, unless the context clearly reflects otherwise it may be directly on, connected or coupled to, or in communication with the other unit, engine, module or block, or there may be intervening units, engines, modules or blocks. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed terms.

[0035] The term "image" in the present disclosure is used to collectively refer to image data (e.g., scan data, projection data) and / or various forms of images, including two-dimensional (2D) images, three-dimensional (3D) images, four-dimensional (4D) images, etc. The terms "pixel" and "voxel" in the present disclosure are used interchangeably to refer to elements of an image. The term "anatomical structure" in the present disclosure may refer to a subject's gas (e.g., air), liquid (e.g., water), solid (e.g., stone), cell, tissue, organ, or any combination thereof that can be displayed in an image (e.g., a second image or a first image, etc.) and actually exists in or on the subject's body. The terms "region", "position", and "area" in the present disclosure may refer to the location of an anatomical structure displayed in an image or the actual location of an anatomical structure that exists in or on the subject's body, because the image may indicate the actual location of a specific anatomical structure that exists in or on the subject's body.

[0036] These and other features and characteristics of the present disclosure, as well as the methods of operation and function of the related structural elements and the combination and economy of manufacture of the parts, may become more apparent upon consideration of the following description with reference to the accompanying drawings, all of which form a part of the present disclosure. However, it should be expressly understood that the drawings are for illustration and description purposes only and are not intended to limit the scope of the present disclosure. It should be understood that the drawings are not drawn to scale.

[0037] The flow chart used in this disclosure illustrates the operation of the system implementation according to some embodiments of the present disclosure. It should be clearly understood that the operation of the flow chart can be implemented out of sequence. On the contrary, these operations can be performed in reverse order or simultaneously. In addition, one or more other operations can be added to the flow chart. One or more operations can be deleted from the flow chart.

[0038] Provided herein are systems and components for non-destructive imaging and / or treatment, for example, for disease diagnosis, treatment or research purposes. In some embodiments, the system may include a radiation therapy (RT) system, a computed tomography (CT) system, an emission computed tomography (ECT) system, an X-ray imaging system, a positron emission tomography (PET) system, a magnetic resonance imaging (MRI) system, or the like, or any combination thereof. For purposes of illustration, the present disclosure describes systems and methods for radiation therapy. The term "image" used in the present disclosure may refer to a 2D image, a 3D image, or a 4D image. In some embodiments, the term "image" may refer to an image of a region of a patient, for example, a region of interest (ROI). The term "region of interest" or "ROI" used in the present disclosure may refer to a portion of an image along a line, in two spatial dimensions, in three spatial dimensions, or any process when they evolve as a function of time. The image may be an electronic portal imaging device (electronic portal imaging device) image, a CT image, a fluoroscopic image, an ultrasound image, a PET image, or an MR image. This is not intended to limit the scope of the present disclosure. For those skilled in the art, a certain number of changes, modifications and / or alterations can be derived under the guidance of the present disclosure. These changes, modifications and / or alterations do not depart from the scope of the present disclosure.

[0039] One aspect of the present disclosure relates to a system and method for dynamic multi-leaf collimator tracking. The system and method can use an electronic portal imaging device (EPID) to track the position of the leaves of a multi-leaf collimator at a control point during radiation therapy or radiation-based imaging of a subject. The system and method can determine an area on the imaging plane of the electronic portal imaging device (a portion of the imaging plane) at the control point. The electronic portal imaging device can only collect imaging data of the area parallel to the direction of motion of the multi-leaf collimator leaves, rather than collecting imaging data of the entire imaging surface. In some embodiments, a working leaf for controlling the shape of the radiation beam at the control point can be identified. In some embodiments, the starting acquisition row and the ending acquisition row of the area can be determined based at least in part on the planned position trajectory of the working leaf. In some embodiments, the sampling rate of the electronic portal imaging device at the control point can be determined based on the planned speed profile of the working leaf for controlling the shape of the radiation beam at the control point. By controlling the electronic portal imaging device to acquire imaging data of the area using a sampling rate at the control point, the amount of imaging data can be reduced, the processing speed can be increased, thereby reducing the motion blur effect of the multi-leaf collimator and improving the measurement accuracy of the working leaf during dynamic multi-leaf collimator tracking.

[0040] Figure 1 is a schematic diagram of an exemplary radiation therapy system 100 according to some embodiments of the present disclosure. The radiation therapy system 100 may include a radiation therapy device 110, a network 120, one or more terminals 130, a processing device 140, and a storage device 150. In some embodiments, two or more components of the radiation therapy system 100 may be connected to and / or communicate with each other via a wireless connection (e.g., the network 120), a wired connection, or a combination thereof. The connections between the components of the radiation therapy system 100 may be variable. By way of example only, the radiation therapy device 110 may be connected to the processing device 140 via the network 120 or directly. As another example, the storage device 150 may be connected to the processing device 140 via the network 120 or directly.

[0041] The radiotherapy device 110 can be used to send a radiotherapy dose to a subject. For example, the radiotherapy device 110 can send one or more radiation beams to a treatment area (e.g., a tumor) of a subject to cause relief of the subject's symptoms. The radiation beam may include a plurality of radiation sub-beams. In the present disclosure, "subject" and "object" can be used interchangeably. The subject can include any biological subject (e.g., a human, an animal, a plant, or a part thereof) and / or a non-biological subject (e.g., a phantom). For example, the subject can include a specific part of the subject's body, such as the head, chest, abdomen, etc., or a combination thereof. In some embodiments, the radiotherapy device 110 can be an image-guided radiotherapy (IGRT) device, a conformal radiotherapy device, an intensity-modulated radiotherapy (IMRT) device, an intensity-modulated arc therapy (IMAT) device, a radiation-guided radiotherapy (EGRT), stereotactic radiosurgery (SRS), stereotactic body radiation therapy (SBRT), etc.

[0042] In some embodiments, the radiotherapy device 110 may include a therapeutic radiation source 111, an electronic portal imaging device (EPID) 112, a viewing table 113, a gantry 114, and a collimator assembly 115. The therapeutic radiation source 111 may be used to emit therapeutic radiation to a subject. In some embodiments, the therapeutic radiation source 111 may be mounted on the gantry 114. The viewing table 113 may be used to support a subject to be treated and / or imaged. In some embodiments, the viewing table 113 may be movable relative to the gantry 114.

[0043] The electronic portal imaging device 112 can be used to acquire images of a subject and / or a collimator assembly 115. In some embodiments, the electronic portal imaging device 112 can be mounted on a gantry 114 and rotate with the gantry 114. In some embodiments, the electronic portal imaging device 112 can include an imaging plane 116 and a detector ( Figure 1 116). In some embodiments, the detector may acquire signals from all or part of the imaging plane 116. In some embodiments, the detector may include one or more detector units. The (multiple) detector units may include scintillation detectors (e.g., cesium iodide detectors, gadolinium oxysulfide detectors), solid detectors, liquid ionization chambers, etc., or any combination thereof. In some embodiments, the imaging radiation source of the electronic portal imaging device may be a therapeutic radiation source 111.

[0044] In some embodiments, the electronic portal imaging device 112 can be at any position associated with a source image distance (SID). For example, the electronic portal imaging device 112 can be 100 cm SID (i.e., the distance between the therapeutic radiation source 111 and the imaging plane 116 of the electronic portal imaging device can be 100 cm). In some embodiments, the center of the therapeutic radiation source 111 and the center of the imaging plane 116 can be aligned. For example, the alignment of the center of the therapeutic radiation source 111 with the center of the imaging plane 116 means that the offset between the center of the therapeutic radiation source 111 and the center of the imaging plane 116 is less than a distance threshold (e.g., 1 mm, 2 mm, etc.).

[0045] The collimator assembly 115 can be used to control the shape of the therapeutic radiation generated by the therapeutic radiation source 111. In some embodiments, the collimator assembly 115 may include a multi-leaf collimator (MLC) located in a multi-leaf collimator plane and at least one jaw located in a jaw plane other than the multi-leaf collimator plane. The multi-leaf collimator may include at least one first set of leaves and at least one second set of leaves that are opposite to each other and movable to form an aperture corresponding to the treatment field by blocking the path of a first portion of the radiation beam within the treatment field. The second portion of the radiation beam may hit the radiation target or a portion thereof located in the treatment field. In some embodiments, there may be a gap between the projection of at least one jaw along the radiation beam direction and the treatment field. At least one jaw may shield or block a portion of the first portion of the radiation beam. The multi-leaf collimator and / or at least one jaw may be made of a radiopaque material. Exemplary radiopaque materials may include tungsten, lead, steel, etc., or alloys thereof, or combinations thereof. In some embodiments, the projection of at least one jaw along the radiation beam direction may partially overlap the treatment area, i.e., form an aperture corresponding to the treatment area together with the multi-leaf collimator.

[0046] The network 120 may include any suitable network that may facilitate information and / or data exchange for the radiotherapy system 100. In some embodiments, one or more components of the radiotherapy system 100 (e.g., the radiotherapy device 110, the terminal(s) 130, the processing device 140, the storage device 150, etc.) may communicate information and / or data with one or more other components of the radiotherapy system 100 via the network 120. For example, the processing device 140 may obtain image data obtained from the radiotherapy device 110 (e.g., the electronic portal imaging device 112 of the radiotherapy device 110) via the network 120. As another example, the processing device 140 may obtain user (e.g., doctor, radiologist) instructions from the terminal(s) 130 via the network 120. The network 120 may be or include a public network (e.g., the Internet), a private network (e.g., a local area network (LAN)), a wired network, a wireless network (e.g., an 802.11 network, a Wi-Fi network), a frame relay network, a virtual private network (VPN), a satellite network, a telephone network, a router, a hub, a switch, a server computer, and / or any combination thereof. For example, the network 120 may include a cable television network, a wired network, a fiber optic network, a telecommunications network, an intranet, a wireless local area network (WLAN), a metropolitan area network (MAN), a public switched telephone network (PSTN), a Bluetooth TM Network, ZigBee TM In some embodiments, the network 120 may include one or more network access points. For example, the network 120 may include a wired and / or wireless network access point, such as a base station and / or an Internet exchange point, through which one or more components of the radiation therapy system 100 may connect to the network 120 to exchange data and / or information.

[0047] The terminal(s) 130 may enable user interaction between the user and the radiotherapy system 100. In some embodiments, the terminal(s) 130 may be connected and / or communicate with the radiotherapy device 110, the processing device 140, and / or the storage device 150. For example, the terminal(s) 130 may display a treatment image of the subject obtained from the processing device 140. In some embodiments, the terminal(s) 130 may include a mobile device 131, a tablet computer 132, a laptop computer 133, etc., or any combination thereof. In some embodiments, the mobile device 131 may include a smart home device, a wearable device, a mobile device, a virtual reality device, an augmented reality device, etc., or any combination thereof. By way of example only, the terminal(s) 130 may include, for example, a Figure 3The mobile device shown. In some embodiments, smart home devices may include smart lighting devices, control devices for smart appliances, smart monitoring devices, smart TVs, smart cameras, intercoms, etc., or any combination thereof. In some embodiments, wearable devices may include bracelets, footwear, glasses, helmets, watches, clothes, backpacks, smart accessories, etc., or any combination thereof. In some embodiments, mobile devices may include mobile phones, personal digital assistants (PDAs), gaming devices, navigation devices, point-of-sale (POS) devices, laptop computers, tablet computers, desktop computers, etc., or any combination thereof. In some embodiments, virtual reality devices and / or augmented reality devices may include virtual reality helmets, virtual reality glasses, virtual reality patches, augmented reality helmets, augmented reality glasses, augmented reality patches, etc., or any combination thereof. For example, virtual reality devices and / or augmented reality devices may include Google Glass. TM 、Oculus Rift TM 、Hololens TM 、GearVR TM Etc. In some embodiments, the terminal(s) 130 may be part of the processing device 140 .

[0048] The processing device 140 may process information obtained from the radiotherapy device 110, the terminal (s) 130, and / or the storage device 150. For example, the processing device 140 may identify multiple working blades of a multi-leaf collimator at a control point, and obtain multiple planned position trajectories and / or multiple planned velocity curves of the multiple working blades. The processing device 140 may determine a signal acquisition area (a portion of an imaging plane) of the electronic portal imaging device 112 based on the multiple planned position trajectories of the control point. As another example, the processing device 140 may determine a sampling rate of the electronic portal imaging device 112 at the control point based on the planned velocity curves of the multiple working blades. As yet another example, the processing device 140 may use the sampling rate at the control point to acquire an image captured by the electronic portal imaging device 112. In some embodiments, the processing device 140 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processing device 140 may be local or remote. For example, the processing device 140 may access information stored in the radiotherapy device 110, the terminal (s) 130, and / or the storage device 150 via the network 120. As another example, the processing device 140 may be directly connected to the radiotherapy device 110, the terminal(s) 130, and / or the storage device 150 to access the stored information. In some embodiments, the processing device 140 may be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, a cross-cloud, a multi-cloud, etc., or any combination thereof. In some embodiments, the processing device 140 may be provided by a computer having a plurality of computer programs such as a computer program product, ... Figure 2 One or more of the components shown may be implemented on a computing device 200 .

[0049] The storage device 150 may store data, instructions, and / or any other information. In some embodiments, the storage device 150 may store data acquired from the radiotherapy device 110, the terminal (s) 130, and / or the processing device 140. For example, the storage device 150 may store a treatment plan for a subject, an image of the subject, and / or a multi-leaf collimator, etc. In some embodiments, the storage device 150 may store data and / or instructions, and the processing device 140 may execute or use these data and / or instructions to perform the exemplary methods described in the present disclosure. In some embodiments, the storage device 150 may include a mass storage device, a removable storage device, a volatile read-write memory, a read-only memory (ROM), etc., or any combination thereof. Exemplary mass storage devices may include magnetic disks, optical disks, solid-state drives, etc. Exemplary removable storage devices may include flash drives, floppy disks, optical disks, memory cards, compact disks, magnetic tapes, etc. Exemplary volatile read-write memory may include random access memory (RAM). Exemplary RAMs may include dynamic RAM (DRAM), double data rate synchronous dynamic RAM (DDR SDRAM), static RAM (SRAM), thyristor RAM (T-RAM), and zero capacitance RAM (Z-RAM). Exemplary ROMs may include mask ROM (MROM), programmable ROM (PROM), erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), compact disk ROM (CD-ROM), and digital versatile disk ROM, etc. In some embodiments, the storage device 150 may be implemented on a cloud platform. By way of example only, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, a cross-cloud, a multi-cloud, etc., or any combination thereof.

[0050] In some embodiments, the storage device 150 may be connected to the network 120 to communicate with one or more other components of the radiation therapy system 100 (e.g., the radiation therapy device 110, the processing device 140, the terminal(s) 130). One or more components of the radiation therapy system 100 may access data and / or instructions stored in the storage device 150 via the network 120. In some embodiments, the storage device 150 may be directly connected to or communicate with one or more other components of the radiation therapy system 100 (e.g., the radiation therapy device 110, the processing device 140, the terminal(s) 130). In some embodiments, the storage device 150 may be part of the processing device 140.

[0051] It should be noted that the above description of the radiotherapy system 100 is only for the purpose of illustration and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various changes and modifications can be made under the teachings of the present disclosure. However, these changes and modifications do not depart from the scope of the present disclosure. In some embodiments, the radiotherapy system 100 may include one or more additional components and / or one or more components of the above-mentioned radiotherapy system 100 may be omitted. For example, the radiotherapy device 110 may also include an imaging component for locating a radiation target or a portion thereof. The imaging component may include a computed tomography (CT) device (e.g., a cone beam CT (CBCT) device, a fan beam CT (FBCT) device, a multi-slice CT (MSCT) device, etc.), a magnetic resonance imaging (MRI) device, an ultrasound imaging device, a fluoroscopic imaging device, a single photon emission computed tomography (SPECT) device, a positron emission tomography (PET) device, an X-ray imaging device, etc., or any combination thereof.

[0052] Figure 2 2 is a schematic diagram of hardware and / or software components of an exemplary computing device 200 according to some embodiments of the present disclosure. The computing device 200 can be used to implement any component of the radiation therapy system 100 as described herein. For example, the processing device 140 and / or the terminal(s) 130 can be implemented on the computing device 200 through their hardware, software programs, firmware, or a combination thereof, respectively. Although only one such computing device is shown, for convenience, the computer functions associated with the radiation therapy system 100 described herein can be implemented in a distributed manner on multiple similar platforms to distribute the processing load. Figure 2 As shown, computing device 200 may include processor 210 , storage device 220 , input / output (I / O) 230 , and communication port 240 .

[0053] The processor 210 can execute computer instructions (e.g., program code) and perform the functions of the processing device 140 according to the techniques described herein. The computer instructions may include, for example, routines, programs, themes, components, data structures, processes, modules, and functions that perform specific functions described herein. For example, the processor 210 can process image data obtained from the radiation therapy device 110, the terminal (s) 130, the storage device 150, and / or any other component of the radiation therapy system 100. In some embodiments, the processor 210 may include one or more hardware processors, such as 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 processing unit (PPU), a microcontroller unit, a digital signal processor (DSP), a field programmable gate array (FPGA), an advanced RISC machine (ARM), a programmable logic device (PLD), any circuit or processor capable of performing one or more functions, etc., or any combination thereof.

[0054] For illustration purposes only, only one processor is described in the computing device 200. However, it should be noted that the computing device 200 in the present disclosure may also include multiple processors, so the operations and / or method operations performed by one processor as described in the present disclosure may also be performed jointly or individually by multiple processors. For example, if the processor of the computing device 200 in the present disclosure performs operation A and operation B simultaneously, it should be understood that operation A and operation B may also be performed jointly or individually by two or more different processors in the computing device 200 (e.g., the first processor performs operation A, the second processor performs operation B, or the first processor and the second processor jointly perform operations A and B).

[0055] The storage device 220 may store data obtained from one or more components of the radiotherapy system 100. In some embodiments, the storage device 220 may include a mass storage device, a removable storage device, a volatile read-write memory, a read-only memory (ROM), etc., or any combination thereof. In some embodiments, the storage device 220 may store one or more programs and / or instructions to perform the exemplary methods described in the present disclosure. For example, the storage device 220 may store a program to be executed by the processing device 140 to determine the signal acquisition area and sampling rate of the electronic portal imaging device 112. As another example, the storage device 220 may store a program to be executed by the processing device 140 to enable the electronic portal imaging device 112 to capture an image based on the signal acquisition area and sampling rate. As yet another example, the processing device 140 may store a program to be executed by the processing device 140 to determine whether the multi-leaf collimator moves according to the planned velocity curve and / or the planned position trajectory.

[0056] I / O 230 can input and / or output signals, data, information, etc. In some embodiments, I / O 230 can enable user interaction with processing device 140. In some embodiments, I / O 230 can include input devices and output devices. Input devices can include alphanumeric keys and other keys that can be input through a keyboard, a touch screen (e.g., through tactile or tactile feedback), voice input, eye tracking input, a brain monitoring system, or any other similar input mechanism. Input information received by the input device can be transmitted to another component (e.g., processing device 140) via, for example, a bus for further processing. Other types of input devices can include cursor control devices, such as a mouse, a trackball, or cursor direction keys, etc. Output devices can include displays (e.g., liquid crystal displays (LCDs), displays based on light emitting diodes (LEDs), flat panel displays, curved screens, television devices, cathode ray tubes (CRTs), touch screens), speakers, printers, etc., or combinations thereof.

[0057] The communication port 240 can be connected to a network (e.g., network 120) to facilitate data communication. The communication port 240 can establish a connection between the processing device 140 and the RT device 110, the terminal (s) 130, and / or the storage device 150. The connection can be a wired connection, a wireless connection, any other communication connection that can enable data transmission and / or reception, and / or any combination of these connections. The wireless connection can include, for example, Bluetooth TM Link, Wi-Fi TM Link, WiMax TM Link, WLAN link, ZigBee TM In some embodiments, the communication port 240 may be a wireless communication port, such as a wireless communication port, a mobile network link (e.g., 3G, 4G, 5G), etc., or a combination thereof. In some embodiments, the communication port 240 may be and / or include a standardized communication port, such as RS232, RS485, etc. In some embodiments, the communication port 240 may be a specially designed communication port. For example, the communication port 240 may be designed according to the Digital Imaging and Communications in Medicine (DICOM) protocol.

[0058] Figure 3 FIG. 3 is a schematic diagram of hardware and / or software components of an exemplary mobile device 300 according to some embodiments of the present disclosure. In some embodiments, one or more terminals 130 and / or processing devices 140 may be implemented on the mobile device 300, respectively.

[0059] like Figure 3As shown, mobile device 300 may include communication platform 310, display 320, graphics processing unit (GPU) 330, central processing unit (CPU) 340, I / O 350, storage 360, and memory 390. In some embodiments, any other suitable components, including but not limited to a system bus or controller (not shown), may also be included in mobile device 300. In some embodiments, mobile operating system 370 (e.g., iOS 11) may be used to control the operation of the mobile device 300. TM 、Android TM 、Windows Phone TM ) and one or more applications 380 may be loaded from memory 390 into storage 360 ​​for execution by CPU 340. Application 380 may include a browser or any other suitable mobile application for receiving and presenting information related to RT system 100. User interaction with the information stream may be accomplished through I / O 350 and provided to processing device 140 and / or other components of RT system 100 through network 120.

[0060] In order to implement the various modules, units and their functions described in this disclosure, a computer hardware platform can be used as a (multiple) hardware platform for one or more elements described herein. A computer with user interface elements can be used to implement a personal computer (PC) or any other type of workstation or terminal device. If properly programmed, a computer can also act as a server.

[0061] Figure 4 is a block diagram of an exemplary processing device 140 according to some embodiments of the present disclosure. Figure 4 As shown, the processing device 140 may include an identification module 410 , a region determination module 420 , a sampling rate determination module 430 , an image acquisition module 440 , and a trajectory error determination module 450 .

[0062] The identification module 410 may be used to identify multiple working leaves of a multi-leaf collimator at a control point. As used herein, multiple working leaves of a multi-leaf collimator at a control point refer to leaves that form an aperture corresponding to a treatment field at the control point.

[0063] The region determination module 420 may be used to determine the signal collection region of the electronic portal imaging device 112. For example, the region determination module 420 may determine the signal collection region of the electronic portal imaging device 112 as a control point based on multiple planned position trajectories of multiple working blades. In some embodiments, the signal collection region may be a region on the imaging plane 116 of the electronic portal imaging device 112, from which one or more detectors of the electronic portal imaging device 112 acquire signals. For example, the signal collection region may be a portion of the imaging plane 116 of the electronic portal imaging device 112.

[0064] The sampling rate determination module 430 can be used to determine the sampling rate of the electronic portal imaging device 112. In some embodiments, the sampling rate determination module 430 can determine the sampling rate of the electronic portal imaging device 112 at the control point based on the planned speed curve of each of the multiple working blades. For example, the sampling rate determination module 430 can obtain the maximum blade speed of the blades among all the blades of the multi-leaf collimator and the maximum sampling rate of the electronic portal imaging device 112. As another example, the sampling rate determination module 430 can obtain the maximum working blade speed of the working blades among the multiple working blades at the control point according to the planned speed curve of each of the multiple working blades. For another example, the sampling rate determination module 430 can determine the sampling rate of the electronic portal imaging device 112 at the control point according to the maximum blade speed, the maximum sampling rate of the electronic portal imaging device, and the maximum working blade speed at the control point.

[0065] The image acquisition module 440 may be used to acquire an image at a control point from the electronic portal imaging device 112. For example, the image acquisition module 440 may acquire an image including information acquired from a signal acquisition region using a sampling rate from the electronic portal imaging device 112.

[0066] The trajectory error determination module 450 can be used to determine the position trajectory error and / or speed curve error of each working blade. For example, the trajectory error determination module 450 can determine the position trajectory error of each working blade based on the planned position trajectory and the measured position trajectory of each working blade. As another example, the trajectory error determination module 450 can determine the speed curve error based on the planned speed curve and the measured speed curve of each working blade.

[0067] It should be noted that the above description of the processing device 140 is for illustrative purposes only and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various modifications and changes may be made to the form and details of the application of the above methods and systems without departing from the principles of the present disclosure. In some embodiments, the processing device 140 may include one or more other modules and / or one or more of the above modules may be omitted. For example, the processing device 140 may also include a transmission module for transmitting a signal (e.g., an electrical signal, an electromagnetic signal) to one or more components of the radiotherapy system 100 (e.g., the radiotherapy device 110, (multiple) terminals 130, a storage device 150). As a further example, the processing device 140 may include a storage module (not shown) for storing information and / or data (e.g., treatment plans, images, etc.) associated with dynamic multi-leaf collimator tracking. Additionally or alternatively, two or more modules may be integrated into a single module and / or the module may be divided into two or more units. For example, the area determination module 420 and the sampling rate determination module 430 can be combined into an electronic portal imaging device parameter determination module for determining the signal acquisition area and sampling rate of the electronic portal imaging device. For another example, the trajectory error determination module 450 can be divided into a position trajectory error determination unit and a velocity curve error determination unit to respectively determine the position trajectory error and velocity curve error of the leaves of the multi-leaf collimator. However, those changes and modifications also fall within the scope of the present disclosure.

[0068] Figure 5 1 is a flow chart of an exemplary process 500 for dynamic multi-leaf collimator tracking according to some embodiments of the present disclosure. In some embodiments, the process 500 may be performed by the radiation therapy system 100. The process 500 may be implemented as a set of instructions (e.g., an application) stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). In some embodiments, the processing device 140 (e.g., processor 210 of computing device 200, CPU 340 of mobile device 300, and / or Figure 4 One or more modules shown) can execute the instruction set and can thereby be directed to perform process 500.

[0069] In 510 , the processing device 140 (eg, the identification module 410 ) may identify a plurality of working leaves of a multi-leaf collimator at a control point.

[0070] In some embodiments, during radiation treatment of a subject, radiation treatment device 110 (e.g., therapeutic radiation source 111, electronic portal imaging device 112, gantry 114, collimator assembly 115) can be rotated around the subject using a plurality of rotation angles relative to an axis perpendicular to examination table 113. In some embodiments, each control point can correspond to a rotation angle in the plurality of rotation angles. In some embodiments, each control point can correspond to a treatment area.

[0071] In some embodiments, the multi-leaf collimator may include at least one first set of leaves and at least one second set of leaves that are relative to each other and can move to form a radiation beam within the aperture treatment range corresponding to the treatment field by blocking the path of the first portion of the multi-leaf collimator. The second portion of the radiation beam can impact a radiation target (e.g., a subject or a portion thereof) located in the treatment field. In some embodiments, the subject may include a biological subject (e.g., a human, an animal), a non-biological subject (e.g., a phantom), etc., or a combination thereof. For example, the subject may include a patient. As another example, the subject may include a specific portion, such as a patient's chest, breast, and / or abdomen. In some embodiments, the radiation target may be an anatomical structure. For example, the radiation target may include an organ, tissue, blood vessel, etc., of the subject, or a combination thereof.

[0072] As used herein, the multiple working leaves of a multi-leaf collimator at a control point refer to the leaves that form an aperture corresponding to the treatment field at the control point. In some embodiments, before the subject is subjected to radiotherapy (e.g., a few days or weeks before the start of treatment), the treatment plan for the subject can be determined. For example, the treatment plan can be determined based on a planned image of the subject captured by an imaging device (e.g., an electronic portal imaging device 112 or an imaging component of a radiotherapy device 110). Using the planned image, one or more radiation targets of the subject can be identified and located. In some embodiments, the treatment plan can describe at least one treatment field applied to the subject at each of the multiple control points. For example, the treatment plan can include a planned fraction duration, a planned radiation dose, a planned radiation energy delivery direction, a planned beam shape of the radiation beam, a planned cross-sectional area of ​​the radiation beam at a specific location along the direction of travel of the radiation beam, a planned region of interest (ROI) (e.g., a radiation target in the subject), etc. or any combination thereof.

[0073] In some embodiments, the processing device 140 may identify a plurality of working leaves based on the treatment plan. For example, the processing device 140 may identify leaves forming a planned beam shape of the radiation beam as a plurality of working leaves. In some embodiments, the processing device 140 may identify a position (or serial number) of each of the plurality of working leaves. The serial number and the position of the working leaf may be mutually determined.

[0074] In 520 , the processing device 140 (eg, the region determination module 420 ) may determine a signal acquisition region of the electronic portal imaging device 112 for the control point based on the plurality of planned position trajectories of the plurality of working blades.

[0075] In some embodiments, the signal acquisition area may be an area on the imaging plane 116 of the electronic portal imaging device 112, from which one or more detectors of the electronic portal imaging device 112 acquire signals. For example, the signal acquisition area may be a portion of the imaging plane 116 of the electronic portal imaging device 112. The signal acquisition area may include at least image information of a treatment area formed by multiple working leaves of a multi-leaf collimator. In some embodiments, one or more detectors may scan the data on the imaging plane 116 line by line to acquire signals for imaging. The direction of the line scan may be parallel to the moving direction of the working leaves of the multi-leaf collimator. In some embodiments, the signal acquisition area may include a plurality of acquisition lines. The plurality of acquisition lines may include a starting acquisition line and an ending acquisition line according to the scanning time. The starting acquisition line may be the first line from which one or more detectors of the electronic portal imaging device 112 acquire signals. The ending acquisition line may be the last line from which one or more detectors of the electronic portal imaging device 112 acquire signals. For example, the imaging plane 116 may be divided into 20 lines along the direction within the leaf arrangement plane of the multi-leaf collimator and perpendicular to the moving direction of the working leaves. For example, the blades of the multi-leaf collimator are arranged in the XY plane, and the working blades move in the X direction to form an aperture that conforms to the treatment field of view, then the imaging plane 116 can be divided into 20 rows along the Y direction. The blades of the multi-leaf collimator can be numbered from the 1st to the 20th. Multiple acquisition rows can include 10 rows. The starting acquisition row can be the 5th row of the 20 rows, and the ending acquisition row can be the 14th row. The signal acquisition area can be a rectangular area between the 5th row and the 14th row, and the two boundaries are adjacent to the imaging plane 116. The two boundaries can be perpendicular to the scanning direction from the 1st row to the 20th row of the blades of the multi-leaf collimator, and vice versa. In some embodiments, each control point can correspond to a signal acquisition area. For example, the processing device 140 can determine the signal acquisition area for each control point.

[0076] In some embodiments, each of the plurality of working blades may have a planned position trajectory. The planned position trajectory may indicate the planned position of the working blade at each time point or each control point during the radiotherapy of the subject. If each working blade moves to a corresponding planned position at a corresponding time point or a corresponding control point, the plurality of working blades may form a treatment area of ​​the treatment plan at the control point. In some embodiments, the plurality of planned position trajectories of the plurality of working blades may be determined based on the treatment plan.

[0077] In some embodiments, the processing device 140 may acquire the blade information of the plurality of working blades based on the planned position trajectory of each working blade in the plurality of working blades. The blade information may include the starting working blade information, the ending working blade information, the center blade information of the multi-leaf collimator, the projection width of the blade projected onto the isocenter plane of the multi-leaf collimator, etc., or any combination thereof. In some embodiments, the starting acquisition row may be the first row of the one or more detectors of the electronic portal imaging device 112 with respect to which the signal is acquired. In some embodiments, the ending acquisition row may be the last row of the one or more detectors of the electronic portal imaging device 112 with respect to which the signal is acquired. In some embodiments, the information of the starting working blade and / or the ending working blade may include the planned position of the starting working blade and / or the ending working blade, the number of the starting working blade and / or the ending working blade, etc., or any combination thereof. In some embodiments, the information of the center blade of the multi-leaf collimator may include information about the position of the center blade of the multi-leaf collimator. In some embodiments, the center blade may be a blade located at the center of the multi-leaf collimator. In some embodiments, the projection width of the blade projected onto the isocenter plane of the multi-leaf collimator may be the width of the blade projected onto the isocenter plane. The isocenter plane may be a plane passing through the isocenter and perpendicular to the beam center axis of the therapeutic radiation source 111. The isocenter plane may be parallel to the imaging plane 116. The beam center axis may be a line passing through the center of the therapeutic radiation source 111 and the center of the plane formed by the radiation beam emitted from the therapeutic radiation source 111. The isocenter point may be a point in space at which the beam center axis of the therapeutic radiation source 111 intersects when the gantry 114 rotates during radiation therapy.

[0078] In some embodiments, the processing device 140 may determine the starting acquisition row and the ending acquisition row in the plurality of acquisition rows (or signal acquisition areas) based on the blade information of the plurality of working blades and the electronic portal imaging device information of the electronic portal imaging device 112. In some embodiments, the electronic portal imaging device information of the electronic portal imaging device 112 may include the pixel size of the electronic portal imaging device 112, the image size of the image captured by the electronic portal imaging device 112, the source image distance (SID), and the offset value of the image. The center of the electronic portal imaging device 112 relative to the beam center axis at the control point, etc., or any combination thereof. In some embodiments, the pixel size of the electronic portal imaging device 112 may be the size of a pixel on the imaging plane 116. The pixel size may be calculated by dividing the size of the imaging plane 116 by a predetermined resolution. In some embodiments, the imaging size of the image captured by the electronic portal imaging device 112 may be the size of the image acquired by the electronic portal imaging device 112. For example, the imaging size may be equal to the size of the imaging plane 116 of the electronic portal imaging device 112. In some embodiments, the SID may be the distance between the therapeutic radiation source 111 and the imaging plane 116. For example, the SID may be 100 cm. In some embodiments, the offset value of the center of the electronic portal imaging device 112 relative to the central axis of the beam may be the distance between the center of the imaging plane 116 and the central axis of the beam. In some embodiments, different rotation angles may correspond to different offset values. For example, if the central axis of the beam of the therapeutic radiation source 111 is perpendicular to the ground (i.e., the rotation angle is 0), the center of the imaging plane 116 may be aligned with the central axis of the beam (the center of the imaging plane 116 is on the central axis of the beam). If the gantry 114 is rotated to an angle exceeding 0 degrees, the center of the imaging plane 116 may be away from the central axis of the beam due to gravity. The distance between the center of the imaging plane 116 and the central axis of the beam may be an offset value. In some embodiments, the offset values ​​corresponding to different rotation angles may be predetermined and stored in a storage device (e.g., storage device 150, storage device 220, memory 390, etc.).

[0079] In some embodiments, the processing device 140 may determine the start acquisition row and the end acquisition row of the signal acquisition area based on the blade information of the plurality of working blades and the electronic portal imaging device information. For example, the processing device 140 may determine the start acquisition row and the end acquisition row at the control point A according to equations (1) and (2), respectively: Wherein StartRow indicates the position of the acquisition row, CenterLeaf indicates the serial number of the center leaf of the multi-leaf collimator, StartLeaf indicates the serial number of the starting working leaf at control point A, EndLeaf indicates the serial number of the ending working leaf at control point A, LeafWidth indicates the projection width of the leaf projected onto the isocenter plane of the multi-leaf collimator at control point A, SID indicates the source image distance at control point A, PanelShift indicates the offset value of the center of the electronic portal imaging device 112 relative to the central axis of the beam at control point A, PixelSize indicates the pixel size of the electronic portal imaging device 112, and ImageSize indicates the image size of the image captured by the electronic portal imaging device 112 at control point A. In some embodiments, the serial number and position of the working leaf can be mutually determined.

[0080] At 530 , the processing device 140 (eg, the image acquisition module 440 ) may acquire an image from the electronic portal imaging device 112 at the control point.

[0081] In some embodiments, the image may include information acquired from the signal acquisition region. For example, for a control point, one or more detectors of the electronic portal imaging device 112 may scan the imaging plane 116 between the start acquisition line and the end acquisition line to acquire information of the signal acquisition region. Figure 6 6 is a schematic diagram of an exemplary signal collection area 620 and an exemplary image 650 according to some embodiments of the present disclosure. Figure 6 As shown, the signal acquisition area 620 may be a portion of the imaging plane 610. The signal acquisition area 620 may include a starting acquisition line 630 and an ending acquisition line 640, and an area between the starting acquisition line 630 and the ending acquisition line 640. One or more detectors of the electronic portal imaging device 112 may scan the imaging plane 610 between the starting acquisition line 630 and the ending acquisition line 640, and may acquire an image 650. The remaining area on the imaging plane 116 other than the signal acquisition area 620 may be assigned a value equal to the value of the pixel shielded by the leaves of the multi-leaf collimator (e.g., a grayscale value of each pixel in the remaining area).

[0082] In some embodiments, the processing device 140 (e.g., the sampling rate determination module 430) may determine the sampling rate of the electronic portal imaging device 112 at the control point based on the planned speed curve of each working blade in the plurality of working blades. In some embodiments, the image may be captured by the electronic portal imaging device 112 using the sampling rate at the control point. In some embodiments, each control point may correspond to a sampling rate. The electronic portal imaging device 112 may capture images using different sampling rates at different control points. In some embodiments, the sampling rate at the control point may be determined based on the speed of the working blade at the control point. Since the working blade does not always move at a high speed (e.g., not less than 25 mm / s), if the electronic portal imaging device 112 always uses a high sampling rate (e.g., not less than 120 frames / s) to capture images, redundant images may be obtained, thereby placing an unnecessary burden on image processing. In some embodiments, the sampling rate at the control point may be proportional to the maximum speed of the working blade in the plurality of working blades at the control point. For example, the electronic portal imaging device 112 may capture more images at a control point M than at a control point N, wherein the maximum speed among the plurality of working blades at the control point M is higher than the maximum speed among the plurality of working blades at the control point N.

[0083] In some embodiments, each of the multiple working blades may have a planned speed curve. The planned speed curve may indicate the planned speed of the working blade at each time point or each control point during the radiotherapy of the subject. If each working blade moves at a corresponding planned speed at a corresponding time point or a corresponding control point, the multiple working blades may form a treatment area specified in the treatment plan at the control point. In some embodiments, multiple planned speed curves of the multiple working blades may be determined based on the treatment plan. In some embodiments, the processing device 140 may obtain the maximum working blade speed of the working blade at the control point from the planned speed curve of each of the multiple working blades. In some embodiments, the processing device 140 may obtain the maximum speed of the working blade of the multiple working blades at the control point from the planned speed curve of each of the multiple working blades. In some embodiments, an exemplary process for determining a sampling rate at a control point may be found elsewhere in the present disclosure (e.g., Figure 7 and its description).

[0084] It should be noted that the above description of process 500 is provided for illustrative purposes only and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various changes and modifications can be made under the guidance of the present disclosure. In some embodiments, process 500 can be completed with one or more additional operations not described and / or without one or more operations discussed above. For example, the processing device 140 can also store the image acquired from the electronic portal imaging device 112 in a storage device (e.g., storage device 150, storage device 220 and / or memory 390). However, these changes and modifications do not depart from the scope of the present disclosure.

[0085] Figure 7 700 is a flowchart of an exemplary process 700 for determining a sampling frequency at a control point according to some embodiments of the present disclosure. In some embodiments, the process 700 may be performed by the radiation therapy system 100. For example, the process 700 may be implemented as a set of instructions (e.g., an application) stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). In some embodiments, the processing device 140 (e.g., processor 210 of computing device 200, CPU 340 of mobile device 300, and / or Figure 4 One or more modules shown) can execute the instruction set and can thereby be directed to perform process 700.

[0086] In 710 , the processing device 140 (eg, the sampling rate determination module 430 ) may obtain a maximum leaf velocity of a leaf among all leaves of a multi-leaf collimator.

[0087] In some embodiments, the maximum blade speed may be the maximum speed at which a blade among all blades of the multi-leaf collimator can move. The maximum blade speed may be a predetermined value and stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). For example, the maximum blade speed may be 25 mm / s. In some embodiments, processing device 140 may access the storage device to obtain the maximum speed.

[0088] At 720 , the processing device 140 (eg, the sampling rate determination module 430 ) may obtain a maximum sampling rate of the electronic portal imaging device 112 .

[0089] In some embodiments, the maximum sampling rate of the electronic portal imaging device 112 may be the maximum rate at which the electronic portal imaging device 112 captures images. The maximum sampling rate may be a predetermined value and stored in a storage device (e.g., the storage device 150, the storage device 220, and / or the memory 390). For example, the maximum sampling rate may be 120 frames per second. In some embodiments, the processing device 140 may access the storage device to obtain the maximum sampling rate.

[0090] In 730 , the processing device 140 (eg, the sampling rate determination module 430 ) may obtain a maximum working blade speed of a working blade among the plurality of working blades at a control point based on a planned speed curve of each working blade among the plurality of working blades.

[0091] In some embodiments, the maximum working blade speed may be the maximum speed of the working blade among the plurality of working blades. In some embodiments, the processing device 140 may obtain the speeds of the plurality of working blades from a planned speed curve of each working blade among the plurality of working blades. The processing device 140 may compare the speeds of the plurality of working blades to identify the maximum working blade speed of the working blade at the control point.

[0092] In 740 , the processing device 140 (eg, the sampling rate determination module 430 ) may determine a sampling rate of the electronic portal imaging device 112 at the control point based on the maximum blade speed, the maximum sampling rate of the electronic portal imaging device, and the maximum operating blade speed at the control point.

[0093] In some embodiments, the processing device 140 may determine the sampling rate of the electronic portal imaging device 112 at the control point according to an algorithm based on the maximum blade speed, the maximum sampling rate of the electronic portal imaging device, and the maximum working blade speed at the control point. For example, the processing device 140 may determine the sampling rate of the electronic portal imaging device 112 at the control point according to equation (3): Where F represents the sampling rate of the electronic portal imaging device 112 at the control point, V MAX-W represents the maximum blade speed of a blade at the control point, V MAX represents the maximum leaf velocity of one leaf among all leaves at the control point of the multi-leaf collimator, F MAX represents the maximum sampling rate of the electronic portal imaging device 112 .

[0094] It should be noted that the above description of process 700 is for illustrative purposes only and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various changes and modifications can be made under the guidance of the present disclosure. In some embodiments, process 700 can be completed with one or more additional operations not described and / or without one or more operations discussed above. For example, the processing device 140 can store the sampling rate of the electronic portal imaging device 112 at the control point in a storage device (e.g., storage device 150, storage device 220 and / or memory 390). However, these changes and modifications do not depart from the scope of the present disclosure.

[0095] Figure 8800 is a flowchart of an exemplary process 800 for determining the position trajectory error and velocity curve error of each working blade according to some embodiments of the present disclosure. In some embodiments, the process 800 can be performed by the radiation therapy system 100. For example, the process 800 can be implemented as a set of instructions (e.g., an application) stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). In some embodiments, the processing device 140 (e.g., the processor 210 of the computing device 200, the CPU 340 of the mobile device 300, and / or Figure 4 One or more modules shown) can execute the instruction set and can therefore be directed to perform process 800.

[0096] At 810 , the processing device 140 (eg, the trajectory error determination module 450 ) may acquire a plurality of images at one of the plurality of control points using a sampling rate, each image corresponding to data acquired by the electronic portal imaging device 112 in a signal acquisition region.

[0097] In some embodiments, processing device 140 may identify multiple control points during radiation therapy of a subject. Electronic portal imaging device 112 may acquire at least one image using a sampling rate at each control point. Each of the at least one image may include data acquired in a signal acquisition region corresponding to each control point.

[0098] At 820 , for each working blade in the plurality of working blades, the processing device 140 (eg, the trajectory error determination module 450 ) may determine a measured position trajectory and a measured velocity profile of each working blade based on the plurality of images.

[0099] In some embodiments, the measured position trajectory may represent the measured position of each working blade at each time point or each control point during the radiotherapy of the subject. In some embodiments, the processing device 140 may synchronize the time points of the plurality of images with the time points of the radiotherapy system 100. For example, the time point of the image may be recorded as the time when the radiotherapy system 100 acquires the image, so that the time points of the plurality of images are synchronized with the time points of the radiotherapy system 100. In some embodiments, after the time synchronization between the plurality of images and the radiotherapy system 100, the processing device 140 may correct one or more of the plurality of images for errors caused by, for example, geometric offsets of the electronic portal imaging device 112, the radiotherapy system 100, etc. For example, the processing device 140 may obtain a plurality of corrected images by correcting the plurality of images based on an image correction algorithm. The image correction algorithm may include a bad pixel correction algorithm, a dark field correction algorithm, a gain correction algorithm, a plate offset correction algorithm, a tilt correction algorithm, a SID correction algorithm, etc. or any combination thereof. In some embodiments, the image correction algorithm may be a correction chart or a correction table. For example, the correction chart or the correction table may include a correction value corresponding to each control point. The processing device 140 may refer to the correction chart or the correction table using the corresponding control point to obtain the corresponding correction value. In some embodiments, the image correction algorithm may be predetermined and stored in a storage device (eg, storage device 150, storage device 220, and / or memory 390).

[0100] In some embodiments, the processing device 140 can determine the measurement position trajectory and measurement speed curve of each working blade based on multiple correction images. In some embodiments, the processing device 140 can identify each working blade in the multiple correction images and obtain the measurement position of each working blade. The processing device 140 can record the measurement position and the corresponding time point of each working blade to obtain the measurement position trajectory of each working blade. The processing device 140 can identify the position that changes over time from the multiple correction images to obtain the measurement speed curve of each working blade. Exemplary processes for determining the measurement position trajectory and measurement speed curve of each working blade can be found elsewhere in this disclosure (e.g., Fig.11 and its description).

[0101] At 830 , for each working blade in the plurality of working blades, the processing device 140 (eg, the trajectory error determination module 450 ) may determine a position trajectory error for each working blade based on the planned position trajectory and the measured position trajectory of each working blade.

[0102] In some embodiments, the position trajectory error of the working blade may represent the difference between the measured position and the planned position of each working blade at each time point or each control point. In some embodiments, the processing device 140 may compare the planned position trajectory with the measured position trajectory of the same working blade to obtain the position trajectory error of the same working blade. Fig. 9 is a schematic diagram of an exemplary planned position trajectory and an exemplary measured position trajectory of a working blade according to some embodiments of the present disclosure. Fig.10 FIG. 1 is a schematic diagram of an exemplary position trajectory error of a working blade according to some embodiments of the present disclosure. Fig. 9 As shown, the planned position trajectory of the working blade is represented by a smooth line, and the measured position trajectory of the working blade is represented by a dashed line. The measured position trajectory can be compared with the planned position trajectory, and the difference between the planned position trajectory and the measured position trajectory can be specified as Fig.10 Position trajectory error shown.

[0103] At 840 , for each working blade in the plurality of working blades, the processing device 140 (eg, the trajectory error determination module 450 ) may determine a velocity profile error for each working blade based on the planned velocity profile and the measured velocity profile for each working blade.

[0104] In some embodiments, the speed curve error of the working blade may represent the difference between the measured speed and the planned speed of each working blade at each time point or each control point. In some embodiments, the processing device 140 may compare the planned speed curve and the measured speed curve of the same working blade to obtain the speed curve error of the same working blade.

[0105] In some embodiments, the planned position and / or velocity of each of the one or more working blades can be determined from the planned position trajectory and / or the planned velocity curve, and the time point corresponding to the planned position and / or velocity of each of the one or more working blades can be determined according to the treatment plan. The time point corresponding to the planned position and / or velocity can be designated as the first time point of the radiotherapy system. The measured position and / or velocity of each of the one or more working blades can be determined from the measured position trajectory and / or the measured velocity curve, and the time point corresponding to the measured position and / or velocity of each of the one or more working blades can be determined. The time point corresponding to the measured position and / or velocity of each of the one or more working blades can be designated as the second time point of the radiotherapy system 100. The first time point of the radiotherapy system 100 and the second time point of the radiotherapy system 100 can be synchronized. In some embodiments, the planned position and / or velocity of the same working blade at each time point can be compared with the measured position and / or velocity, and the position error and / or velocity error at each time point can be obtained, thereby obtaining the position trajectory error and / or velocity curve error of the working blade.

[0106] In some embodiments, the velocity curve error and / or position trajectory error of each working blade can be used to evaluate the dynamic error of each working blade during radiation therapy of the subject. In some embodiments, the velocity curve error and / or position trajectory error of each working blade can be compared with a predetermined threshold to determine whether each working blade moves according to the treatment plan.

[0107] It should be noted that the above description of process 800 is for illustrative purposes only and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various changes and modifications can be made under the guidance of the present disclosure. In some embodiments, process 800 can be completed with one or more additional operations not described and / or without one or more operations discussed above. For example, processing device 140 can store multiple images at multiple control points in a storage device (e.g., storage device 150, storage device 220 and / or memory 390). However, those changes and modifications do not depart from the scope of the present invention.

[0108] Fig.111 is a schematic diagram of an exemplary process 1100 for obtaining a measurement position trajectory and a measurement velocity curve according to some embodiments of the present disclosure. In some embodiments, the process 1100 can be performed by the radiation therapy system 100. For example, the process 1100 can be implemented as a set of instructions (e.g., an application) stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). In some embodiments, the processing device 140 (e.g., the processor 210 of the computing device 200, the CPU 340 of the mobile device 300, and / or Figure 4 One or more modules shown) can execute the instruction set and can therefore be directed to perform process 1100.

[0109] In some embodiments, process 1100 may be performed for each working blade in a plurality of working blades. In 1110, processing device 140 (eg, trajectory error determination module 450) may obtain pixel locations for each working blade in each correction image in a plurality of correction images.

[0110] In some embodiments, each working leaf may be represented as a plurality of pixels on the corrected image. For example, the processing device 140 may identify the plurality of pixels based on an edge gradient algorithm or a 50% gray value point algorithm. The processing device 140 may identify the pixel positions of the plurality of pixels in each corrected image.

[0111] In 1120 , the processing device 140 (eg, the trajectory error determination module 450 ) may determine a field position corresponding to each pixel position based on a predetermined mapping relationship between pixel positions and field positions.

[0112] In some embodiments, the predetermined mapping relationship may include multiple mapping pairs. The mapping pair may include a pixel position and a corresponding field position. The predetermined mapping relationship may be predetermined and stored in a storage device (e.g., storage device 150, storage device 220, and / or memory 390). The processing device 140 may use each pixel position to look up the preset mapping relationship to obtain the corresponding field position.

[0113] In 1130 , the processing device 140 (eg, the trajectory error determination module 450 ) may obtain a measured position trajectory and a measured velocity curve of each working blade based on the field position corresponding to each pixel position and the time synchronization signal.

[0114] In some embodiments, the time synchronization signal can be used to synchronize a first measurement time of the measured position trajectory with a first planned time of the planned position trajectory. In some embodiments, the time synchronization signal can be used to synchronize a second measurement time of the measured speed curve with a second planned time of the planned speed curve. The processing device 140 can determine the trajectory of the measured position over time as the measured position trajectory based on the field position corresponding to each pixel position. The processing device 140 can determine the trajectory of the measured speed over time as the measured speed curve based on the field position corresponding to each pixel position. In some embodiments, the processing device 140 can determine the trajectory of the measured position with radiation dose and / or with rotation angle as the measured position trajectory. The measured position trajectory with radiation dose and / or rotation angle can be compared with the corresponding planned position trajectory with radiation dose and / or rotation angle to evaluate the dynamic error of multiple working blades at each control point.

[0115] It should be noted that the above description of process 1100 is only for the purpose of illustration and is not intended to limit the scope of the present disclosure. For those of ordinary skill in the art, various changes and modifications can be made under the guidance of the present disclosure. In some embodiments, process 1100 can be completed with one or more additional operations not described and / or without one or more operations discussed above. However, these changes and modifications do not depart from the scope of the present disclosure.

[0116] The basic concepts have been described above. Obviously, for those skilled in the art, the above detailed disclosure is only for example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.

[0117] At the same time, the application uses specific words to describe the embodiments of the application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present disclosure. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the application can be appropriately combined.

[0118] In addition, it will be appreciated by those skilled in the art that various aspects of the present application may be illustrated and described by a number of patentable categories or situations, including any new and useful process, machine, product or combination of substances, or any new and useful improvements thereto. Accordingly, various aspects of the present application may be performed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The above hardware or software may all be referred to as "data blocks", "modules", "engines", "units", "components" or "systems". In addition, various aspects of the present application may be represented as a computer product located in one or more computer-readable media, which includes computer-readable program code.

[0119] A computer storage medium may include a propagated data signal containing computer program code, for example, in baseband or as part of a carrier wave. The propagated signal may be in a variety of forms, including electromagnetic, optical, etc., or a suitable combination. A computer storage medium may be any computer-readable medium other than a computer-readable storage medium, which can be connected to an instruction execution system, device or apparatus to communicate, propagate or transmit the program for use. The program code on the computer storage medium may be transmitted via any suitable medium, including radio, cable, fiber optic cable, RF, or similar media, or any combination of the above media.

[0120] The computer program coding required for the operation of each part of the application can be written in any one or more programming languages, including object-oriented programming languages ​​such as Java, Scala, Smalltalk, Eiffel, JADE, Emerald, C++, C#, VB.NET, Python, etc., conventional procedural programming languages ​​such as C language, VisualBasic, Fortran2003, Perl, COBOL2002, PHP, ABAP, dynamic programming languages ​​such as Python, Ruby and Groovy, or other programming languages, etc. The program coding can be run completely on the user's computer, or run on the user's computer as an independent software package, or run partly on the user's computer and partly on the remote computer, or run completely on the remote computer or server. In the latter case, the remote computer can be connected to the user's computer through any network form, such as a local area network (LAN) or a wide area network (WAN), or connected to an external computer (e.g., via the Internet), or in a cloud computing environment, or used as a service such as software as a service (SaaS).

[0121] In addition, unless explicitly stated in the claims, the order of the processing elements and sequences described in this application, the use of alphanumeric characters, or the use of other names are not intended to limit the order of the processes and methods of this application. Although the above disclosure discusses some invention embodiments that are currently considered useful through various examples, it should be understood that such details are only for illustrative purposes, and the attached claims are not limited to the disclosed embodiments. On the contrary, the claims are intended to cover all modifications and equivalent combinations that are consistent with the essence and scope of the embodiments of this application. For example, although the system components described above can be implemented by hardware devices, they can also be implemented only by software solutions, such as installing the described system on an existing server or mobile device.

[0122] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more embodiments of the invention, in the above description of the embodiments of this application, multiple features are sometimes merged into one embodiment, drawing or description thereof. However, this disclosure method does not mean that the subject of this application requires more features than those mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.

Claims

1. A method for dynamic multi-leaf collimator tracking, characterized in that: include: identifying a plurality of working leaves of a multi-leaf collimator at a control point; as well as Based on the planned velocity profile of each of the plurality of working blades, a sampling rate of the electronic portal imaging device at the control point is determined.

2. The method according to claim 1, characterized in that Determining the sampling rate of the electronic portal imaging device at the control point comprises: Obtaining a maximum leaf velocity of all leaves of the multi-leaf collimator; Obtaining a maximum sampling rate of the electronic portal imaging device; Based on the planned speed curve of each working blade in the plurality of working blades, obtaining the maximum working blade speed of the working blades in the plurality of working blades at the control point; and The electronic portal imaging device sampling rate at the control point is determined based on the maximum blade speed, the maximum sampling rate of the electronic portal imaging device and the maximum operating blade speed at the control point.

3. The method according to claim 1, characterized in that The plurality of planned velocity profiles for the plurality of working blades are determined based on a treatment plan.

4. The method according to claim 1, characterized in that Also includes: acquiring a plurality of images, each of the plurality of images corresponding to data acquired by the electronic portal imaging device using a sampling rate of one of a plurality of control points in the signal acquisition region; as well as For each working blade in the plurality of working blades, Based on the multiple images, determining a measurement position trajectory and a measurement speed curve of each working blade; Determining a position trajectory error of each working blade based on the planned position trajectory and the measured position trajectory of each working blade; as well as Based on the planned speed profile and the measured speed profile of each working blade, a speed profile error of each working blade is determined.

5. The method according to claim 4, characterized in that Determining the measurement position trajectory and the measurement speed curve of each working blade based on the multiple images includes: Based on an image correction algorithm, obtaining a plurality of corrected images by correcting the plurality of images; and Based on the plurality of corrected images, the measured position trajectory and the measured speed curve of each working blade are determined.

6. The method according to claim 5, characterized in that Based on the multiple corrected images, determining the measurement position trajectory and the measurement speed curve of each working blade comprises: For each working blade in the plurality of working blades, Obtaining a pixel position for each working blade in each of the plurality of corrected images; Determining the field position corresponding to each pixel position based on the predetermined mapping relationship between the pixel position and the field position; and Based on the field position and time synchronization signal corresponding to each pixel position, the measurement position trajectory and the measurement speed curve of each working blade are obtained, wherein the time synchronization signal is configured to synchronize a first measurement time of the measurement position trajectory with a first planned time of the planned position trajectory, and to synchronize a second measurement time of the measurement speed curve with a second planned time of the planned speed curve.

7. The method according to any one of claims 1 to 6, characterized in that: Also includes: Based on the multiple planned position trajectories of the multiple working blades, determining a signal collection area of ​​the electronic portal imaging device for the control point, wherein the signal collection area is a portion of an imaging plane of the electronic portal imaging device, and one or more detectors of the electronic portal imaging device collect signals from the signal collection area; as well as An image is acquired from the electronic portal imaging device at the control point, wherein the image includes information acquired in the signal acquisition region.

8. The method according to claim 7, characterized in that Determining the signal acquisition area of ​​the electronic portal imaging device for the control point includes: Based on the planned position trajectory of each working blade in the plurality of working blades, acquiring blade information of the plurality of working blades; and Based on the blade information of the plurality of working blades and the electronic portal imaging device information of the electronic portal imaging device, a start acquisition row and an end acquisition row of the plurality of acquisition rows are determined.

9. The method according to claim 8, characterized in that The plurality of planned position trajectories of the plurality of working blades are determined based on a treatment plan.

10. A system for dynamic multi-leaf collimator tracking, comprising at least one storage device including a set of instructions for dynamic multi-leaf collimator tracking; and at least one processor in communication with the at least one storage device, wherein: When executing the set of instructions, the at least one processor is directed to cause the system to perform the method as claimed in any one of claims 1-9.

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