WO2020029148A1 - 一种放疗设备准直器校正方法及装置 - Google Patents

一种放疗设备准直器校正方法及装置 Download PDF

Info

Publication number
WO2020029148A1
WO2020029148A1 PCT/CN2018/099483 CN2018099483W WO2020029148A1 WO 2020029148 A1 WO2020029148 A1 WO 2020029148A1 CN 2018099483 W CN2018099483 W CN 2018099483W WO 2020029148 A1 WO2020029148 A1 WO 2020029148A1
Authority
WO
WIPO (PCT)
Prior art keywords
collimator
positions
percentage
ray projection
projection image
Prior art date
Application number
PCT/CN2018/099483
Other languages
English (en)
French (fr)
Inventor
李久良
闫浩
李金升
苟天昌
罗春
Original Assignee
西安大医集团有限公司
深圳市奥沃医学新技术发展有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 西安大医集团有限公司, 深圳市奥沃医学新技术发展有限公司 filed Critical 西安大医集团有限公司
Priority to PCT/CN2018/099483 priority Critical patent/WO2020029148A1/zh
Priority to CN201880008605.1A priority patent/CN111010868B/zh
Publication of WO2020029148A1 publication Critical patent/WO2020029148A1/zh
Priority to US17/005,699 priority patent/US11227700B2/en

Links

Images

Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/02—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators
    • G21K1/025—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators using multiple collimators, e.g. Bucky screens; other devices for eliminating undesired or dispersed radiation
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
    • A61B6/06—Diaphragms
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
    • A61B6/08—Auxiliary means for directing the radiation beam to a particular spot, e.g. using light beams
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
    • A61B6/54—Control of apparatus or devices for radiation diagnosis
    • A61B6/545—Control of apparatus or devices for radiation diagnosis involving automatic set-up of acquisition parameters
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N5/00—Radiation therapy
    • A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
    • A61N5/1042—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy with spatial modulation of the radiation beam within the treatment head
    • A61N5/1045—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy with spatial modulation of the radiation beam within the treatment head using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
    • A61N5/00—Radiation therapy
    • A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
    • A61N5/1077—Beam delivery systems
    • A61N5/1084—Beam delivery systems for delivering multiple intersecting beams at the same time, e.g. gamma knives
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
    • A61B6/54—Control of apparatus or devices for radiation diagnosis
    • A61B6/542—Control of apparatus or devices for radiation diagnosis involving control of exposure
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/02—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diaphragms, collimators

Definitions

  • the invention relates to the field of medical instruments, and in particular, to a method and a device for calibrating a collimator of a radiotherapy device.
  • the principle of the gamma knife device is to use a collimator to make the gamma rays emitted from the radiation source exit from the collimation hole on the collimator and focus it to the focal point, and then kill the lesion cells at the focal point.
  • a motor to drive the collimator to move to a predetermined position, so that the collimation hole on the collimator is aligned with the radiation source.
  • the inventors of the present invention have found that with the increase in the number of uses of the gamma knife device, the accuracy of the drive motor decreases, and improper operation during use causes problems such as collimator offset. In this way, the collimation hole on the collimator and the radiation source may not be accurately aligned, and the focus penumbra at the focal point may be too large, and the dose may be biased. Therefore, a method is needed to correct the position of the collimator of the gamma knife device.
  • Embodiments of the present invention provide a method and a device for correcting a collimator of a radiotherapy device, which can correct a position of a collimator of a gamma knife device.
  • an embodiment of the present invention provides a method for correcting a collimator of a radiotherapy device, which method comprises: when the collimator is moved to M positions, sequentially passing through the collimation holes on the collimator, and the radiotherapy device.
  • determining the target position with the highest degree of alignment of the collimator from M positions according to the ray projection image includes: determining the position from M positions according to the gray value and penumbra value of the ray projection image. Collimator aligns to the highest target position.
  • determining the target position with the highest degree of alignment of the collimator from M positions according to the ray projection image includes: generating a ray projection image when the collimator is moved to M positions according to the ray projection image.
  • First, second, and third percentage dose lines, where the second percentage (first percentage + third percentage) / 2; calculate collimator movement separately
  • the similarity T of the second percentage dose line of the ray projection image to the corresponding theoretical second percentage dose line at the M positions and the calculation of the ray projection image of the ray projection image when the collimator moves to the M positions, respectively.
  • the distance L between the first percentage dose line and the third percentage dose line; according to the similarity T and the distance L, the target position is determined.
  • the first percentage, the second percentage, and the third percentage dose line of the ray projection image include: according to the ray projection
  • the gray value of the image generates the first, second, and third percentage dose lines of the ray projection image when the collimator is moved to M positions, respectively.
  • determining the target position according to the similarity T and the distance L includes: calculating the alignment parameter q of the collimation hole corresponding to the ray projection image when the collimator moves to M positions according to the similarity T and the distance L; When the collimator is moved to M positions, the weighting average of the alignment parameters q of the collimation holes corresponding to the ray projection image is used to calculate the total alignment parameter Q; the position with the largest total alignment parameter Q among the M positions is determined as the target position.
  • the radiotherapy equipment includes a radiation source and a collimator.
  • the collimator includes a plurality of collimation holes, and the radiation emitted by the radiation source is focused to the center of the radiotherapy equipment and the like through the plurality of collimation holes.
  • an embodiment of the present invention further provides a collimator calibration device for a radiotherapy apparatus, including:
  • the acquisition unit is used to obtain the ray projection images after the collimator is moved to M positions, and passes through the center plane of the collimator, the radiotherapy equipment and other center planes in sequence;
  • the M positions include: collimator design Position and at least one other position whose displacement difference from the design position is less than a preset distance;
  • the design position is: a theoretical position where the collimator is aligned; a determining unit for determining the alignment accuracy from M positions according to the ray projection image
  • the recording unit is used to record position parameters corresponding to the target position, so that the collimator is controlled to move to the target position during treatment with the radiotherapy device.
  • the determining unit is specifically configured to determine a target position with the highest degree of alignment of the collimator from the M positions according to the gray value and the penumbra value of the ray projection image.
  • the dose line generating subunit is specifically configured to generate the first percentage and the second percentage of the ray projection image when the collimator is moved to M positions according to the gray value of the ray projection image.
  • Third third dose line is specifically configured to generate the first percentage and the second percentage of the ray projection image when the collimator is moved to M positions according to the gray value of the ray projection image.
  • determining a subunit is specifically used to calculate an alignment parameter q of a collimation hole corresponding to the ray projection image when the collimator moves to M positions according to the similarity T and the distance L; the collimator moves to The alignment parameters q of the collimation holes corresponding to the ray projection images at the M positions are weighted and averaged to calculate the total alignment parameter Q; the position with the largest total alignment parameter Q among the M positions is determined as the target position.
  • the radiotherapy equipment includes a radiation source and a collimator.
  • the collimator includes a plurality of collimation holes, and the radiation emitted by the radiation source is focused to the center of the radiotherapy equipment and the like through the plurality of collimation holes.
  • an embodiment of the present invention provides another collimator calibration device for radiotherapy equipment, including: a processor, a memory, a bus, and a communication interface; the memory is used to store a computer to execute instructions, and the processor and the memory are connected through the bus.
  • the processor executes computer execution instructions stored in the memory, so that the radiotherapy device collimator calibration device executes the radiotherapy device collimator calibration method according to any one of claims 1-6.
  • an embodiment of the present invention provides a computer storage medium, which includes instructions that, when run on a computer, causes the computer to execute the method for correcting a collimator of a radiotherapy apparatus according to the first aspect.
  • an embodiment of the present invention provides a computer program product including instructions, which is characterized in that when it is run on a computer, the computer is caused to perform the collimator calibration of the radiotherapy apparatus according to any one of claims 1-6. method.
  • the collimator by obtaining projection images of the rays received by the ray detector when the collimator is at the design position before correction and at M positions near the design position, one of the M positions is selected according to the projection image.
  • the collimator is aligned with the highest target position and recorded, so that the collimator can be driven to the target position when the next treatment with the gamma knife device is performed, and the position of the collimator during the treatment is corrected.
  • the focus of the rays at the isocenter is more concentrated, so that the patient receives a higher dose at the tumor and a less dose at the non-tumor area.
  • FIG. 1 is a schematic structural diagram of a focusing treatment head in a gamma knife device
  • FIG. 2 is a schematic structural diagram of a gamma knife device
  • FIG. 3 is a schematic structural diagram of a gamma knife device according to an embodiment of the present invention.
  • FIG. 4 is a schematic flowchart of a method for correcting a collimator of a radiotherapy device according to an embodiment of the present invention
  • FIG. 5 is a schematic flowchart of another method for correcting a collimator of a radiotherapy apparatus according to an embodiment of the present invention.
  • FIG. 6 is a schematic structural diagram of a collimator calibration device for a radiotherapy apparatus according to an embodiment of the present invention.
  • FIG. 7 is a schematic structural diagram of another collimator correction device for a radiotherapy apparatus according to an embodiment of the present invention.
  • FIG. 8 is a schematic structural diagram of another collimator calibration device for a radiotherapy apparatus according to an embodiment of the present invention.
  • a component can be, but is not limited to being: a process running on a processor, a processor, an object, an executable, a thread in execution, a program, and / or a computer.
  • an application running on a computing device and the computing device may be a component.
  • One or more components can reside within a process and / or thread of execution and a component may be localized on one computer and / or distributed between two or more computers.
  • these components can execute from various computer readable media having various data structures thereon.
  • These components can be used, for example, by having data grouped with one or more data (e.g., data from a component that interacts with another component in the local system, a distributed system, and / or through a signal such as the Internet Network to interact with other systems) to communicate in a local and / or remote process.
  • data e.g., data from a component that interacts with another component in the local system, a distributed system, and / or through a signal such as the Internet Network to interact with other systems
  • exemplary is used to indicate an example, illustration, or description. Any embodiment or design described as “example” in this application should not be construed as more preferred or advantageous over other embodiments or designs. Rather, the word using examples is intended to present concepts in a concrete way.
  • information, signal, and message may sometimes be mixed. It should be noted that when the difference is not emphasized, the meanings to be expressed are the same. “Of”, “corresponding, relevant” and “corresponding” can sometimes be used interchangeably. It should be noted that when the difference is not emphasized, the meanings to be expressed are the same.
  • the words “first” and “second” are used to distinguish between the same or similar items having substantially the same functions and functions.
  • the skilled person can understand that the words “first”, “second” and so on are not limiting the quantity and execution order.
  • Gamma Knife is the main treatment method of Stereotactic Radiosurgery.
  • the lesion tissue in the skull is selectively determined as the target.
  • the gamma produced by cobalt-60 is used.
  • the radiation is focused and irradiated at one time in large doses to cause focal necrosis or functional changes, thereby achieving the purpose of treating diseases.
  • the treatment principle of the Gamma Knife is similar to the focusing process of a magnifying glass. Place the magnifying glass in the sun, and a dazzling spot, the focal point, will form under the magnifying glass. Outside the focus, people feel as usual, but there is high heat at the focus, which is enough to ignite some objects.
  • Gamma knife equipment is a radiotherapy device that uses gamma knife treatments to perform treatments.
  • the focusing treatment head emits radiation from human tissues in different directions. These rays are focused at the target point (focus), so that the irradiation dose at the target point is sufficient to kill the diseased tissue, while other human tissues are only exposed to a small dose, so Will cause damage.
  • FIG. 1 it is a schematic structural diagram of a focus treatment head 10 in a gamma knife device. These include the radiation source 101 and the collimator 102. During the treatment, the radiation emitted by the radiation source 101 passes through the collimation hole in the collimator 102 and will be transmitted in a predetermined propagation direction.
  • the collimator 102 may include a pre-collimator 1021 and a final collimator 1022.
  • the pre-collimator 1021 is relatively fixed to the radiation source in terms of mechanical structure
  • the final collimator 1022 may include a plurality of groups of final collimation holes with different apertures to form different-sized fields at the focal point.
  • one of a plurality of sets of final collimation holes with different apertures is aligned with the pre-collimator 1021 by the rotation of the motor to kill the tumor tissue at the focal point.
  • FIG. 1 only shows the structure of the radiation source and the collimation hole corresponding to one beam of rays in the focused treatment head.
  • FIG. 2 is a schematic structural diagram of a focus treatment head 20.
  • the focus treatment head 20 includes a radiation source 201 and a collimator 202.
  • the collimator 202 includes a pre-collimator 2021 and a final collimator. Group 2022.
  • the pre-collimator 2021 has five pre-collimation holes
  • the final collimator group 2022 includes two final collimation hole groups, where each final collimation hole group includes five final collimation holes.
  • the final collimator group 2022 By rotating the final collimator group 2022, one of the two final collimator groups on the final collimator group 2022 is aligned with the pre-collimation hole, so that the radiation passes through the pre-collimation hole and the final collimation hole. Formation of a shooting field. For example, turn the final collimator group 2022 clockwise to align the left collimator group with the pre-collimator, which is the state shown in Figure 2; you can also reverse the final collimator group 2022 Turn it clockwise to align the right end collimator with the pre-collimator. It should be noted that the number of collimation holes on the collimator in the focus treatment head shown in FIG. 2 above is only exemplary, and the number of collimation holes can be designed according to needs in specific applications, which is not limited in the present invention. .
  • the invention provides a collimator calibration method and device, which can automatically complete the calibration of the collimator and improve the treatment effect of the gamma knife device.
  • an embodiment of the present invention provides a method for calibrating a collimator of a radiotherapy device. This method is used in radiotherapy equipment.
  • the radiotherapy equipment referred to in the embodiment of the present invention may specifically be a gamma knife device, or a radiotherapy device that uses other rays for treatment and requires a collimator to be calibrated. The invention does not limit this.
  • the radiotherapy apparatus 30 includes a focused treatment head, and the focused treatment head includes a radiation source 301 and a collimator 302. It should be noted that, in FIG. 3, only two collimation holes on the radiation source 301 and the collimator 302 are shown by way of example. In actual radiotherapy equipment, the number of collimation holes in the collimator 302 is set according to actual needs, so that the radiation emitted by the radiation source is emitted from different angles and focused at the isocenter.
  • the focus treatment head is disposed on the drum 304.
  • the focusing treatment head can rotate with the rotation of the drum 304.
  • the collimator 302 is movable within a predetermined position range relative to the radiation source 301. When the collimator moves to a predetermined position range, as shown in FIG. 3, the radiation source 301 generates at least one beam through at least one collimation hole. And shoot towards the isocenter.
  • the radiotherapy apparatus 30 may further include a radiation detector 303. As shown in FIG.
  • the radiation detector 303 may be disposed on the drum 304 at a position opposite to the focusing treatment head, so that the radiation can be irradiated on the radiation after passing through the center of the collimator hole, the radiotherapy equipment and the like on the collimator.
  • the detector 303 is used to obtain a ray projection image after passing through a center plane such as a collimation hole, a radiotherapy device, and the like on the collimator.
  • the collimator 302 referred to in the embodiment of the present invention refers to a collective name of a collimating component having at least one collimating hole group and capable of aligning the collimating hole group with a radiation source through movement.
  • the collimator 302 involved in the embodiment of the present invention refers to Final collimator group 2022.
  • the method for correcting a collimator of a radiotherapy device specifically includes:
  • center plane such as radiotherapy equipment in the embodiment of the present invention refers to a plane where the center of the radiotherapy equipment and the like is perpendicular to the line connecting the treatment head and the radiation detector.
  • the M positions include: the design position of the collimator 302 and at least one other position whose displacement difference from the design position is less than a preset distance; the design position is a theoretical position where the collimator 302 is aligned.
  • the collimator 302 is fine-tuned by the motor to make the collimator 302 is offset 0.5mm and 1mm to the left from the set position, and 0.5mm and 1mm to the right from the set position.
  • the set position is shifted to the left by 0.5mm
  • the set position is shifted to the left by 1mm
  • the set position is shifted to the right by 0.5mm
  • the set position is shifted to the right by 1mm.
  • a target position that has the highest degree of alignment of the collimator 302 is determined from the M positions.
  • a target position with the highest degree of alignment of the collimator can be determined from the M positions.
  • a projection image with the smallest penumbra and the largest gray level is selected from the M projection images acquired at the M positions, and the projection image is corresponding to Position as the target position.
  • the target position information or the driving parameters of the servo motor corresponding to the target position may be recorded in a configuration file of the radiotherapy apparatus. Later, when the radiotherapy equipment is used for the treatment, the servo motor can be controlled to rotate according to the target position information or driving parameters, thereby driving the collimator 302 to move to the target position.
  • a collimator is selected from the highest alignment degree. According to the selected target position, the position of the collimator is corrected.
  • the focus of the rays at the isocenter is more concentrated, so that the patient receives a higher dose at the tumor and a less dose at the non-tumor area.
  • an embodiment of the present invention further provides a method for calibrating a collimator of a radiotherapy device, which is used in the radiotherapy device.
  • a gamma knife device used in this method, reference may be made to the description of the gamma knife device described above, and duplicated details will not be repeated. Specifically, as shown in FIG. 5, the method includes:
  • the focusing head includes five radiation sources 301
  • the collimator 302 includes a set of collimation holes
  • the set of collimation holes includes 5 collimation holes.
  • Obtain the collimator 302 at the set position the set position is shifted to the left by 0.5mm, the set position is shifted to the left by 1mm, the set position is shifted to the right by 0.5mm, and the set position is shifted to the right by 1mm.
  • five beams of rays pass through the center plane of the collimator hole, radiotherapy equipment, and other ray projection images, and then 5 ray projection images can be acquired, each of which includes the ray projection images. The projection of five rays.
  • the first, second, and third percentage dose lines of the ray when the collimator 302 moves to M positions can be generated according to the gray values of the ray projection image.
  • the dose-gray value function can be fitted according to the correspondence curve between the dose and the gray value of the projected image. Then, according to the gray values corresponding to the first percentage, the second percentage, and the third percentage of the dose, the first percentage and the second percentage of the rays are fitted in the projection image. Third third dose line.
  • the first percentage, the second percentage, and the third percentage in the embodiments of the present invention may be set to values of 20%, 50%, and 80, respectively. %.
  • the target position is determined by using the similarity T and the distance L to make the correction effect better.
  • step S504 specifically includes:
  • weighting ratios can be set for the similarity T and the distance L according to the degree of influence of the alignment degree of the similarity T and the distance L on the collimator.
  • the weight of the similarity T is set to 80%
  • the weight of the distance L is set to 20%.
  • the present invention is not limited.
  • the collimator 302 includes five collimation holes, and the collimator 302 is rotated at two positions 0.5mm and 1.0mm to the left of the design position, and a projection image is obtained.
  • Tables 1 and 2 show the similarity T, distance L, and alignment parameter q of the five collimation holes when the collimator 302 is 0.5 mm to the left of the design position.
  • Table 2 shows When the collimator 302 is 1.0 mm to the left of the design position, the similarity T of the five collimation holes, the value of the distance L, and the finally calculated alignment parameter q.
  • the total alignment parameter Q of the collimator 302 at the position 0.5mm to the left of the design position can be calculated:
  • collimator 302 is 1.0mm to the left of the design position, and the total alignment parameter Q:
  • the 1.0 mm position to the left of the design position is written into the configuration file of the radiotherapy device as the optimal alignment position of the collimator 302.
  • an embodiment of the present application further provides a collimator calibration device for a radiotherapy device.
  • the radiotherapy equipment collimator correction device 60 provided in this embodiment may be installed in the radiotherapy equipment, so that the radiotherapy equipment can be periodically aligned with the collimator for automatic calibration.
  • the collimator correction device 60 of the radiotherapy apparatus includes an obtaining unit 601, a determining unit 602, and a recording unit 603. among them:
  • An obtaining unit 601 is used to obtain the ray projection images after the collimator moves to M positions, and sequentially passes through the center plane of the collimator hole, the radiotherapy equipment and other center planes;
  • the M positions include: the collimator The design position and at least one other position whose displacement difference from the design position is less than a preset distance;
  • the design position is: a theoretical position where the collimator is aligned;
  • a determining unit 602 configured to determine a target position with the highest degree of alignment of the collimator from the M positions according to the ray projection image;
  • the recording unit 603 is configured to record a position parameter corresponding to the target position, so that the collimator is controlled to move to the target position during treatment with the radiotherapy equipment.
  • the determining unit 602 is specifically configured to determine a target position with the highest degree of alignment of the collimator from the M positions according to the gray value and the penumbra value of the ray projection image.
  • the determination unit 602 specifically includes: a dose line generation subunit 6021, a calculation subunit 6022, and a determination subunit 6023;
  • a calculation subunit 6022 configured to calculate the similarity T of the second percentage dose line of the ray projection image and the corresponding theoretical second percentage dose line respectively when the collimator moves to M positions; The distance L between the first percentage dose line and the third percentage dose line of the ray projection image when the collimator is moved to M positions;
  • a determining subunit 6023 is configured to determine a target position according to the similarity T and the distance L.
  • the determining subunit 6023 is specifically configured to calculate the alignment parameter q of the collimation hole corresponding to the ray projection image when the collimator moves to M positions according to the similarity T and the distance L; the collimator moves The alignment parameters q of the collimation holes corresponding to the ray projection images when weighted to M positions are averaged to calculate the total alignment parameter Q; the position with the largest total alignment parameter Q among the M positions is determined as the target position.
  • FIG. 7 shows a possible structural diagram of a collimator calibration device for a radiotherapy apparatus involved in the above embodiment.
  • the radiotherapy equipment collimator correction device 70 includes a processing module 701 and a communication module 702.
  • the processing module 701 is used to control and manage the actions of the collimator correction device 70 of the radiotherapy equipment.
  • the processing module 701 is used to support the collimator correction device 70 of the radiotherapy equipment to perform S402-S403 in FIG. 4, S502-S505 in FIG. 5, and the like.
  • the steps further implement the functions of the determining unit 602 and the recording unit 603 in FIG. 6 described above through the processing module 701.
  • the communication module 702 is configured to support communication between the radiation therapy device collimator correction device 70 and other physical devices.
  • the communication module 702 is configured to communicate with a ray detector and obtain a ray projection image from the ray detector after passing through a center plane such as a collimation hole on the collimator, a radiotherapy device, etc. to complete S401 and FIG. 4
  • the steps of S501 in FIG. 5 are to enable the communication module 702 to implement the function of the obtaining unit 601 in FIG. 6.
  • the radiotherapy equipment collimator correction device 70 may further include a storage module 703 for storing program codes and data of the radiotherapy equipment collimator correction device 70.
  • the processing module 701 may be a processor or a controller, for example, it may be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), and an application-specific integrated circuit (Application-Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logical blocks, modules, and circuits described in connection with the present disclosure.
  • the processor may also be a combination that implements computing functions, such as a combination including one or more microprocessors, a combination of a DSP and a microprocessor, and so on.
  • the communication module 702 may be a transceiver, a transceiver circuit, or a communication interface.
  • the storage module 703 may be a memory.
  • the radiotherapy equipment collimator correction device may be calibrated for the radiotherapy equipment collimator shown in FIG. 8 Device.
  • the collimator calibration device 80 for a radiotherapy apparatus includes a processor 801, a communication interface 802, a memory 803, and a bus 804.
  • the communication interface 802, the processor 801, and the memory 803 are connected to each other through a bus 804.
  • the bus 804 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. Wait.
  • PCI Peripheral Component Interconnect
  • EISA Extended Industry Standard Architecture
  • Wait The bus can be divided into an address bus, a data bus, a control bus, and the like. For ease of representation, only a thick line is shown in FIG. 8, but it does not mean that there is only one bus or one type of bus.
  • the steps of the method or algorithm described in combination with the disclosure of the present invention may be implemented in a hardware manner, or may be implemented in a manner in which a processor executes software instructions.
  • An embodiment of the present invention further provides a storage medium.
  • the storage medium may include a memory 803 for storing computer software instructions used by the collimator calibration device of the radiotherapy apparatus, which includes performing the collimator calibration of the radiotherapy apparatus provided in the foregoing embodiment.
  • the software instructions may be composed of corresponding software modules, and the software modules may be stored in random access memory (RAM), flash memory, read-only memory (ROM), erasable and programmable memory.
  • EPROM Erasable Programmable ROM
  • EPROM Electrically Erasable Programmable Read Only Memory
  • registers hard disk, mobile hard disk, read-only optical disk (CD-ROM), or any other form of storage known in the art Media.
  • An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium.
  • the storage medium may also be an integral part of the processor.
  • the embodiment of the present invention also provides a computer program, which can be directly loaded into the memory 803 and contains software code. After the computer program is loaded and executed by the computer, the radiotherapy device collimator provided in the foregoing embodiment can be implemented. Correction method.
  • the functions described in the present invention may be implemented by hardware, software, firmware, or any combination thereof.
  • the functions may be stored on a computer-readable medium or transmitted as one or more instructions or code on a computer-readable medium.
  • Computer-readable media includes computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another.
  • a storage media may be any available media that can be accessed by a general purpose or special purpose computer.
  • an embodiment of the present invention further provides a gamma knife device.
  • the structure of the gamma knife device can refer to FIG. 3, and includes a radiation source, a collimator, a ray detector, and an implementation as described above.
  • the collimator correction device of the radiotherapy equipment provided by the example.
  • the ray detector is used to receive the ray after passing through the collimation hole on the collimator and the center plane of the radiotherapy equipment and generate a ray projection image, and send the ray projection image to the collimator calibration device of the radiotherapy equipment.
  • the ray detector can be realized by the electronic field imaging device EPID.

Landscapes

  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biomedical Technology (AREA)
  • Medical Informatics (AREA)
  • Veterinary Medicine (AREA)
  • Pathology (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Radiology & Medical Imaging (AREA)
  • Physics & Mathematics (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Biophysics (AREA)
  • Optics & Photonics (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Molecular Biology (AREA)
  • Surgery (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • General Engineering & Computer Science (AREA)
  • Radiation-Therapy Devices (AREA)

Abstract

一种准直器校正方法及装置，涉及医疗器械领域。该方法包括：分别获取准直器（302）移动至M个位置处时，依次穿过准直器（302）上的准直孔和等中心平面之后的射线投影图像（S401）；根据射线投影图像，从M个位置中确定出使准直器（302）对准程度最高的目标位置（S402）；记录目标位置对应的位置参数，以使得在利用伽玛刀设备治疗时控制准直器（302）移动至目标位置（S403）。能够对伽玛刀设备的准直器（302）的位置进行校正。

Description

一种放疗设备准直器校正方法及装置 技术领域
本发明涉及医疗器械领域，尤其涉及一种放疗设备准直器校正方法及装置。
背景技术
目前，利用伽玛刀设备进行放射治疗已成为***的重要手段。伽玛刀设备的原理为利用准直器使放射源发出的伽玛射线从准直器上的准直孔射出并聚焦到焦点处，进而对焦点处的病灶细胞进行杀伤。现有的伽玛刀设备中，在进行治疗时，需要利用电机驱动准直器移动至预定位置，以使得准直器上准直孔与放射源对准。
本发明发明人发现，随着伽玛刀设备的使用次数的增加，驱动电机精度下降，以及使用中操作不当等原因，会产生准直器偏移的问题。这样一来，就可能会导致准直器上准直孔与放射源不能精确对准，进而使焦点处聚焦半影过大，以及剂量存在偏差。因此需要一种方法来对伽玛刀设备的准直器的位置进行校正。
发明内容
本发明实施例提供一种放疗设备准直器校正方法及装置，能够对伽玛刀设备的准直器的位置进行校正。
为了达到上述目的，本发明的实施例采用如下技术方案：
第一方面，本发明实施例提供一种放疗设备准直器校正方法，该方法包括：分别获取准直器移动至M个位置处时，依次穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像；M个位置包括：准直器设计位置以及与设计位置的位移差小于预设距离的至少一个其他位置；设计位置为：准直器对准的理论位置；根据射线投影图像， 从M个位置中确定出使准直器对准程度最高的目标位置；记录目标位置对应的位置参数，以使得在利用放疗设备治疗时控制准直器移动至目标位置。
可选的，根据射线投影图像，从M个位置中确定出使准直器对准程度最高的目标位置包括：根据射线投影图像的灰度值和半影值，从M个位置中确定出使准直器对准程度最高的目标位置。
可选的，根据射线投影图像，从M个位置中确定出使准直器对准程度最高的目标位置包括：根据射线投影图像，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中第二百分比＝(第一百分比+第三百分比)/2；分别计算准直器移动至M个位置处时射线投影图像的第二百分比剂量线与对应地理论第二百分比剂量线的相似度T；以及分别计算准直器移动至M个位置处时射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L；根据相似度T和距离L，确定目标位置。
可选的，根据射线投影图像，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线包括：根据射线投影图像的灰度值，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线。
可选的，根据相似度T和距离L，确定目标位置包括：根据相似度T和距离L，计算准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q；对准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q；将M个位置中总对准参数Q最大的位置确定为目标位置。
可选的，放疗设备包括放射源、准直器，准直器上包括多个准直孔，放射源发出的射线通过多个准直孔聚焦至放疗设备等中心。
第二方面，本发明实施例还提供一种放疗设备准直器校正装置，包括：
获取单元，用于分别获取准直器移动至M个位置处时，依次穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像；M个位置包括：准直器设计位置以及与设计位置的位移差小于预设距离的 至少一个其他位置；设计位置为：准直器对准的理论位置；确定单元，用于根据射线投影图像，从M个位置中确定出使准直器对准程度最高的目标位置；记录单元，用于记录目标位置对应的位置参数，以使得在利用放疗设备治疗时控制准直器移动至目标位置。
可选的，确定单元，具体用于根据射线投影图像的灰度值和半影值，从M个位置中确定出使准直器对准程度最高的目标位置。
可选的，确定单元，具体包括：剂量线生成子单元、计算子单元以及确定子单元；剂量线生成子单元，用于根据射线投影图像，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中第二百分比＝(第一百分比+第三百分比)/2；计算子单元，用于分别计算准直器移动至M个位置处时射线投影图像的第二百分比剂量线与对应地理论第二百分比剂量线的相似度T；以及分别计算准直器移动至M个位置处时射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L；确定子单元，用于根据相似度T和距离L，确定目标位置。
可选的，剂量线生成子单元，具体用于根据射线投影图像的灰度值，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线。
可选的，确定子单元，具体用于根据相似度T和距离L，计算准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q；对准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q；将M个位置中总对准参数Q最大的位置确定为目标位置。
可选的，放疗设备包括放射源、准直器，准直器上包括多个准直孔，放射源发出的射线通过多个准直孔聚焦至放疗设备等中心。
第三方面，本发明实施例提供另一种放疗设备准直器校正装置，包括：处理器、存储器、总线和通信接口；存储器用于存储计算机执行指令，处理器与存储器通过总线连接，当放疗设备准直器校正装置运行时，处理器执行存储器存储的计算机执行指令，以使放疗设备准直器校正装置执行如权利要求1-6中任一项的放疗设备准直器校正方 法。
第四方面，本发明实施例提供一种计算机存储介质，其特征在于，包括指令，当其在计算机上运行时，使得计算机执行如上述第一方面的放疗设备准直器校正方法。
第五方面，本发明实施例提供一种包含指令的计算机程序产品，其特征在于，当其在计算机上运行时，使得计算机执行如权利要求1-6中任一项的放疗设备准直器校正方法。
本发明实施例中，通过获取准直器在校正前的设计位置及设计位置附近的M个位置处时射线探测器接收到的射线的投影图像，根据投影图像，从M个位置中选择出一个使准直器对准程度最高的目标位置并记录，以使得下次利用伽玛刀设备治疗时能够驱动准直器至该目标位置，实现对治疗时准直器的位置的校正。使等中心点的射线聚焦更加集中，让患者在肿瘤处剂量更大，非肿瘤处少受剂量。
附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的附图。
图1为一种为伽玛刀设备中聚焦治疗头的结构示意图；
图2为一种伽玛刀设备的结构示意图；
图3为本发明的实施例所提供的一种伽玛刀设备的结构示意图；
图4为本发明的实施例所提供的一种放疗设备准直器校正方法的流程示意图；
图5为本发明的实施例所提供的另一种放疗设备准直器校正方法的流程示意图；
图6为本发明的实施例所提供的一种放疗设备准直器校正装置的结构示意图；
图7为本发明的实施例所提供的另一种放疗设备准直器校正装置 的结构示意图；
图8为本发明的实施例所提供的又一种放疗设备准直器校正装置的结构示意图。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
如本申请所使用的，术语“单元”、“组件”、“模块”、“***”等等旨在指代计算机相关实体，该计算机相关实体可以是硬件、固件、硬件和软件的结合、软件或者运行中的软件。例如，组件可以是，但不限于是：在处理器上运行的处理、处理器、对象、可执行文件、执行中的线程、程序和/或计算机。作为示例，在计算设备上运行的应用和该计算设备都可以是组件。一个或多个组件可以存在于执行中的过程和/或线程中，并且组件可以位于一个计算机中以及/或者分布在两个或更多个计算机之间。此外，这些组件能够从在其上具有各种数据结构的各种计算机可读介质中执行。这些组件可以通过诸如根据具有一个或多个数据分组(例如，来自一个组件的数据，该组件与本地***、分布式***中的另一个组件进行交互和/或以信号的方式通过诸如互联网之类的网络与其它***进行交互)的信号，以本地和/或远程过程的方式进行通信。
本申请将围绕可包括多个设备、组件、模块等的***来呈现各个方面、实施例或特征。应当理解和明白的是，各个***可以包括另外的设备、组件、模块等，并且/或者可以并不包括结合附图讨论的所有设备、组件、模块等。此外，还可以使用这些方案的组合。
另外，在本发明实施例中，“示例的”一词用于表示作例子、例证或说明。本申请中被描述为“示例”的任何实施例或设计方案不应被解释为比其它实施例或设计方案更优选或更具优势。确切而言，使用示 例的一词旨在以具体方式呈现概念。
本发明实施例中，信息(information)，信号(signal)，消息(message)有时可以混用，应当指出的是，在不强调其区别时，其所要表达的含义是一致的。“的(of)”，“相应的(corresponding，relevant)”和“对应的(corresponding)”有时可以混用，应当指出的是，在不强调其区别时，其所要表达的含义是一致的。
为了便于清楚描述本发明实施例的技术方案，在本发明的实施例中，采用了“第一”、“第二”等字样对功能和作用基本相同的相同项或相似项进行区分，本领域技术人员可以理解“第一”、“第二”等字样并不是在对数量和执行次序进行限定。
首先，对本发明所涉及的专业术语进行介绍：
伽玛刀，Gamma Knife，是立体定向放射外科(Stereotactic Radiosurgery)的主要治疗手段，是根据立体定向几何原理，将颅内的病变组织选择性地确定为靶点，使用钴-60产生的伽玛射线进行一次性大剂量地聚焦照射，使之产生局灶性的坏死或功能改变，而达到治疗疾病的目的。伽玛刀的治疗原理类似于放大镜的聚焦过程。把放大镜置于阳光下，放大镜下面会形成一个耀眼夺目的光斑，即焦点。焦点以外的地方，人的感觉如常，但在焦点处却有很高的热度，足以使一些物体点燃。
伽玛刀设备，是利用伽玛刀治疗手段实施治疗的放疗设备。其中聚焦治疗头会从不同方向人体组织发射射线，这些射线在靶点(焦点)处聚焦，使靶点处的照射剂量足够杀死病变组织，而其他人体组织仅受到少剂量的照射，因此不会产生损伤。如图1所示，为伽玛刀设备中的聚焦治疗头10的一种结构示意图。其中包括放射源101以及准直器102，在进行治疗时，放射源101发出的射线通过准直器102上的准直孔后将按照预定的传播方向传播。具体的，如图中所示，准直器102可以包括预准直器1021和终准直器1022。其中预准直器1021在机械结构上与放射源是相对固定的，终准直器1022则可以包括多组不同孔径的终准直孔，以在焦点处形成不同大小的射野。在治疗时通过电机旋转让多组不同孔径的终准直孔中的一组与预准直器1021对准，用于 杀死位于焦点处的肿瘤组织。另外，图1中仅示出了聚焦治疗头中一束射线对应的放射源、准直孔的结构，在实际应用时伽玛刀设备上聚焦治疗头中会包括多束射线。示例性的，图2所示为一种聚焦治疗头20的结构示意图，该聚焦治疗头20中包括放射源201和准直器202，准直器202包括预准直器2021以及终准直器组2022。具体的，预准直器2021上有5个预准直孔，终准直器组2022中包括2个终准直孔组，其中每个终准直孔组中包括5个终准直孔。在治疗中通过旋转终准直器组2022，使终准直器组2022上2个终准直器组中的一个对准预准直孔，以使射线通过预准直孔、终准直孔形成射野。例如，将终准直器组2022顺时针转动，以使左侧的终准直器组与预准直器对准，即图2中所表现的状态；也可以将终准直器组2022逆时针转动，以使右侧的终准直器与预准直器对准。需要说明的是，上述图2中所示聚焦治疗头中准直器上的准直孔个数仅为示例性的，具体应用时可根据需要设计准直孔个数，本发明对此不作限制。
以下对本发明的发明原理进行介绍：在现有的伽玛刀设备上，通常依靠机械和电气的设计以及光栅尺来保证放射源与准直器的对准。在验证放射源与准直器是否对准时，往往采用在等中心放上胶片并打开准直器进行曝光，利用胶片上呈现的图像，来对伽玛刀设备整体的聚焦程度进行验证，这种验证方法无法获知单个准直孔的对准情况，无法有效指导准直器的调整。因此目前现有技术中缺少一种行之有效的校正准直器的方法。本发明提供一种准直器校正方法及装置，能够自动完成准直器的校正工作，提高伽玛刀设备的治疗效果。
基于上述发明原理，本发明实施例提供一种放疗设备准直器校正方法。该方法应用于放疗设备中。本发明实施例中所称放疗设备，具体可以是伽玛刀设备，也可以是利用其他射线进行治疗且需要校正准直器的放疗设备。本发明对此不作限制。
如图3所示，该放疗设备30包括聚焦治疗头，聚焦治疗头内包括放射源301、准直器302。需要说明的是，图3中仅示例性的画出了放射源301以及准直器302上的两个准直孔。在实际放疗设备中，准直器302上的准直孔的个数根据实际需要进行设定，以便使放射源发出 的射线从不同角度射出并在等中心处聚焦。
其中如图3所示，聚焦治疗头设置在滚筒304上。该聚焦治疗头可随滚筒304的转动而转动。准直器302相对于放射源301可在预定位置范围内移动，在准直器移动至预定位置范围内时，如图3中所示，放射源301通过至少一个准直孔产生至少一束射线并射向等中心。另外，该放疗设备30还可以包括射线探测器303。如图3中所示，射线探测器303可设置在滚筒304上与聚焦治疗头相对的位置上，以便当射线穿过准直器上的准直孔、放疗设备等中心后，能够照射在射线探测器303上，从而利用射线探测器303获取穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像。
具体的，本发明实施例中所称准直器302指：至少具有一个准直孔组，且能够通过运动使准直孔组与放射源对准的准直部件的统称。示例性的，如图2所示的放疗设备中包括位置相对固定的预准直器2021和可以运动的终准直器组2022时，则本发明实施例中所涉及的准直器302则指终准直器组2022。
如图4所示，该放疗设备准直器校正方法，具体包括：
S401、分别获取准直器302移动至M个位置处时，依次穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像。
需要说明的是，本发明实施例中所称“放疗设备等中心平面”指放疗设备等中心所在的垂直于治疗头和射线探测器连线的平面。
其中，M个位置包括：准直器302的设计位置以及与设计位置的位移差小于预设距离的至少一个其他位置；设计位置为：准直器302对准的理论位置。
示例性的，在其设定位置(即校正前，准直器结构设计时，获得的该终准直器与放射源对准的位置)左右，通过电机微调准直器302，使准直器302分别从设定位置向左偏移0.5mm、1mm，再从设定位置向右偏移0.5mm、1mm。
然后分别获取准直器302移动至设定位置、设定位置向左偏移0.5mm、设定位置向左偏移1mm、设定位置向右偏移0.5mm、设定位置向右偏移1mm，这五个位置处时，射线探测器接收到的射线的投影 图像。
S402、根据射线投影图像，从M个位置中确定出使准直器302对准程度最高的目标位置。
具体的，可以根据射线投影图像的灰度值和半影值，从M个位置中确定出使准直器对准程度最高的目标位置。
例如，当准直器302分别处于M个位置处时，从M个位置所获取的M张投影图像中选出投影图像中半影最小且灰度最大的投影图像，并将该投影图像对应的位置作为目标位置。在根据射线投影图像的灰度值和半影值确定目标位置时，可以根据半影值和灰度值对准直器对准程度的影响大小，对半影值和灰度值设置不同的权重比例。例如，设置半影值的权重为80％，灰度值的权重为20％。对于具体的权重大小，本发明不做限制。
S403、记录目标位置对应的位置参数，以使得在利用放疗设备治疗时控制准直器移动至目标位置。
具体的，可以在确定目标位置后，将该目标位置信息或目标位置所对应的伺服电机的驱动参数记录在放疗设备的配置文件中。之后在利用放疗设备进行治疗时，可以控制伺服电机按照目标位置信息或驱动参数旋转，进而驱动准直器302移动至目标位置。
本发明实施例中，通过获取准直器在校正前的设计位置及设计位置附近的多个位置处时，射线探测器接收到的射线的投影图像，从中选择出一个准直器对准程度最高的目标位置，进而根据选择出的目标位置，实现对准直器位置的校正。使等中心点的射线聚焦更加集中，让患者在肿瘤处剂量更大，非肿瘤处少受剂量。
在一种实施例中，考虑到根据射线投影图像从M个位置中确定出使准直器302对准程度最高的目标位置时，具体可根据射线的剂量线与理论剂量线的相似度以及射线的聚焦程度的相关参数来进行计算并判断。进而本发明实施例还提供了一种放疗设备准直器校正方法，用于放疗设备中。用于本方法的伽玛刀设备可参照上文中对伽玛刀设备的描述，重复之处不再赘述。具体的，如图5所示，该方法包括：
S501、分别获取准直器302移动至M个位置处时，依次穿过准直 器上的准直孔、放疗设备等中心平面之后的射线投影图像。
示例性的，假设聚焦头包括5颗放射源301，准直器302包括一组准直孔，该一组准直孔包括5个准直孔。分别获取准直器302在设定位置、设定位置向左偏移0.5mm、设定位置向左偏移1mm、设定位置向右偏移0.5mm、设定位置向右偏移1mm，这五个位置处时，五束射线穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像，进而能够获取到5张射线投影图像，其中每张射线投影图像中都包括了五束射线的投影。
S502、根据射线投影图像，分别生成准直器302移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中第二百分比＝(第一百分比+第三百分比)/2。
其中，可以根据射线投影图像的灰度值，分别生成准直器302移动至M个位置处时，射线的第一百分比、第二百分比、第三百分比剂量线。
具体的，根据剂量与投影图像的灰度值的对应关系曲线，能够拟合出剂量-灰度值函数。然后再根据射线的第一百分比、第二百分比、第三百分比剂量分别对应的灰度值，在投影图像中拟合出射线的第一百分比、第二百分比、第三百分比剂量线。
在一种实施例中，为了得到更好的检测结果，本发明实施例中第一百分比、第二百分比、第三百分比，可分别取值为20％、50％、80％。
S503、分别计算准直器302移动至M个位置处时射线投影图像的第二百分比剂量线与对应的理论第二百分比剂量线的相似度T；以及分别计算准直器302移动至M个位置处时射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L。
S504、根据相似度T和距离L，确定目标位置。
由于当剂量线与理论剂量线的相似度越高时，说明对应的准直孔的位置越接近理想位置；同时剂量线之间的距离越小时，则说明等中心处聚焦更加集中，进而就能让患者在肿瘤处剂量更大，非肿瘤处少受剂量。因此本发明实施例中，利用相似度T和距离L来确定目标位置，以使校正效果更好。
在一种实现方式中，步骤S504具体包括：
S5041、根据相似度T和距离L，计算准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q。
其中距离L一定时，相似度T越大，对应的准直参数q越大；相似度T一定时，距离L越小，对应的准直参数q越大。
在根据相似度T和距离L确定目标位置时，可以根据相似度T和距离L对准直器对准程度的影响大小，对相似度T和距离L设置不同的权重比例。例如，设置相似度T的权重为80％，距离L的权重为20％。对于具体的权重大小，本发明不做限制。
S5042、对准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q。
S5043、选出M个位置中总对准参数Q最大的目标位置。
例如：准直器302包括5个准直孔，将准直器302分别在设计位置的左侧0.5mm、1.0mm两个位置进行了转动并获取投影图像。测量结果如下表1、表2，其中表1为准直器302在设计位置左侧0.5mm位置处时5个准直孔的相似度T、距离L的值以及对准参数q，表2为准直器302在设计位置左侧1.0mm位置处时5个准直孔的相似度T、距离L的值以及最终计算出的对准参数q。
Figure PCTCN2018099483-appb-000001
表1
Figure PCTCN2018099483-appb-000002
表2
进而可以计算出准直器302在设计位置左侧0.5mm位置处，总对准参数Q：
(80％+67％+85％+80％+89％)/5＝80.2％；
以及准直器302在设计位置左侧1.0mm位置处，总对准参数Q：
(89％+85％+85％+91％+88％)/5＝87.6％。
因此，将设计位置左侧1.0mm位置作为准直器302对准最佳的位置写入放疗设备的配置文件中。
S505、记录目标位置对应的位置参数，以使得在利用放疗设备治疗时控制准直器移动至目标位置。
另一方面，基于上述放疗设备准直器校正方法，本申请实施例还提供一种放疗设备准直器校正装置。示例性的，本实施例提供的放疗设备准直器校正装置60可安装在放疗设备中，从而可以使放疗设备定期对准直器进行自动校正。本实施例中所放疗设备可参照上文中对放疗设备的描述，在此不再赘述。具体的，如图6所示，该放疗设备准直器校正装置60包括获取单元601、确定单元602、记录单元603。其中：
获取单元601，用于分别获取准直器移动至M个位置处时，依次穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像；M个位置包括：准直器设计位置以及与设计位置的位移差小于预设距离的至少一个其他位置；设计位置为：准直器对准的理论位置；
确定单元602，用于根据射线投影图像，从M个位置中确定出使准直器对准程度最高的目标位置；
记录单元603，用于记录目标位置对应的位置参数，以使得在利 用放疗设备治疗时控制准直器移动至目标位置。
可选的，确定单元602，具体用于根据射线投影图像的灰度值和半影值，从M个位置中确定出使准直器对准程度最高的目标位置。
可选的，确定单元602，具体包括：剂量线生成子单元6021、计算子单元6022、确定子单元6023；
剂量线生成子单元6021，用于根据射线投影图像，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中第二百分比＝(第一百分比+第三百分比)/2；
计算子单元6022，用于分别计算准直器移动至M个位置处时射线投影图像的第二百分比剂量线与对应地理论第二百分比剂量线的相似度T；以及分别计算准直器移动至M个位置处时射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L；
确定子单元6023，用于根据相似度T和距离L，确定目标位置。
可选的，具体用于根据射线投影图像的灰度值，分别生成准直器移动至M个位置处时，射线投影图像的第一百分比、第二百分比、第三百分比剂量线。
可选的，确定子单元6023，具体用于根据相似度T和距离L，计算准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q；对准直器移动至M个位置处时射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q；将M个位置中总对准参数Q最大的位置确定为目标位置。
由于本申请实施例中的准直器校正装置可以应用于实施上文所提供的方法实施例，因此，其所能获得的技术效果也可参考上述方法实施例，本申请实施例在此不再赘述。
在采用集成的单元的情况下，附图7示出了上述实施例中所涉及的放疗设备准直器校正装置的一种可能的结构示意图。放疗设备准直器校正装置70包括：处理模块701和通信模块702。处理模块701用于对放疗设备准直器校正装置70的动作进行控制管理，例如处理模块701用于支持放疗设备准直器校正装置70执行图4中S402-S403、图5中 S502-S505等步骤，进而通过处理模块701实现上述图6中确定单元602和记录单元603的功能。通信模块702用于支持放疗设备准直器校正装置70与其他实体设备的通信。例如，通信模块702用于与射线探测器进行通信，并从射线探测器中获取穿过准直器上的准直孔、放疗设备等中心平面之后的射线投影图像，以完成图4中S401和图5中S501的步骤，以使通信模块702实现图6中获取单元601的功能。放疗设备准直器校正装置70还可以包括储存模块703，用于存储放疗设备准直器校正装置70的程序代码和数据。
其中，处理模块701可以是处理器或控制器，例如可以是中央处理器(Central Processing Unit，CPU)，通用处理器，数字信号处理器(Digital Signal Processor，DSP)，专用集成电路(Application-Specific Integrated Circuit，ASIC)，现场可编程门阵列(Field Programmable Gate Array，FPGA)或者其他可编程逻辑器件、晶体管逻辑器件、硬件部件或者其任意组合。其可以实现或执行结合本发明公开内容所描述的各种示例性的逻辑方框，模块和电路。所述处理器也可以是实现计算功能的组合，例如包含一个或多个微处理器组合，DSP和微处理器的组合等等。通信模块702可以是收发器、收发电路或通信接口等。储存模块703可以是存储器。
当处理模块701为处理器，通信模块702为通信接口，储存模块703为存储器时，本发明实施例所涉及的放疗设备准直器校正装置可以为附图8所示的放疗设备准直器校正装置。
参阅附图8所示，该放疗设备准直器校正装置80包括：处理器801、通信接口802、存储器803以及总线804。其中，通信接口802、处理器801以及存储器803通过总线804相互连接；总线804可以是外设部件互连标准(Peripheral Component Interconnect，PCI)总线或扩展工业标准结构(Extended Industry Standard Architecture，EISA)总线等。所述总线可以分为地址总线、数据总线、控制总线等。为便于表示，附图8中仅用一条粗线表示，但并不表示仅有一根总线或一种类型的总线。
结合本发明公开内容所描述的方法或者算法的步骤可以硬件的方式来实现，也可以是由处理器执行软件指令的方式来实现。本发明实施例 还提供一种存储介质，该存储介质可以包括存储器803，用于储存放疗设备准直器校正装置所用的计算机软件指令，其包含执行上述实施例中提供的放疗设备准直器校正方法所设计的程序代码。具体的，软件指令可以由相应的软件模块组成，软件模块可以被存放于随机存取存储器(Random Access Memory，RAM)、闪存、只读存储器(Read Only Memory，ROM)、可擦除可编程只读存储器(Erasable Programmable ROM，EPROM)、电可擦可编程只读存储器(Electrically EPROM，EEPROM)、寄存器、硬盘、移动硬盘、只读光盘(CD-ROM)或者本领域熟知的任何其它形式的存储介质中。一种示例性的存储介质耦合至处理器，从而使处理器能够从该存储介质读取信息，且可向该存储介质写入信息。当然，存储介质也可以是处理器的组成部分。
本发明实施例还提供一种计算机程序，该计算机程序可直接加载到存储器803中，并含有软件代码，该计算机程序经由计算机载入并执行后能够实现上述实施例所提供的放疗设备准直器校正方法。
本领域技术人员应该可以意识到，在上述一个或多个示例中，本发明所描述的功能可以用硬件、软件、固件或它们的任意组合来实现。当使用软件实现时，可以将这些功能存储在计算机可读介质中或者作为计算机可读介质上的一个或多个指令或代码进行传输。计算机可读介质包括计算机存储介质和通信介质，其中通信介质包括便于从一个地方向另一个地方传送计算机程序的任何介质。存储介质可以是通用或专用计算机能够存取的任何可用介质。
在另一种实施例中，本发明实施例还提供一种伽玛刀设备，该伽玛刀设备的结构可参照图3所示，包括放射源、准直器、射线探测器以及如上述实施例所提供的放疗设备准直器校正装置。其中射线探测器用于接收穿过准直器上的准直孔以及放疗设备等中心平面之后的射线并生成射线投影图像，并将射线投影图像发送至放疗设备准直器校正装置。
其中射线探测器可以利用电子射野影像装置EPID来实现。
以上所述的具体实施方式，对本发明的目的、技术方案和有益效果进行了进一步详细说明，所应理解的是，以上所述仅为本发明的具体实 施方式而已，并不用于限定本发明的保护范围，凡在本发明的技术方案的基础之上，所做的任何修改、等同替换、改进等，均应包括在本发明的保护范围之内。

Claims (15)

  1. 一种放疗设备准直器校正方法，其特征在于，所述方法包括：
    分别获取所述准直器移动至M个位置处时，依次穿过所述准直器上的准直孔、放疗设备等中心平面之后的射线投影图像；所述M个位置包括：所述准直器设计位置以及与所述设计位置的位移差小于预设距离的至少一个其他位置；所述设计位置为：所述准直器对准的理论位置；
    根据所述射线投影图像，从所述M个位置中确定出使所述准直器对准程度最高的目标位置；
    记录所述目标位置对应的位置参数，以使得在利用所述放疗设备治疗时控制所述准直器移动至所述目标位置。
  2. 根据权利要求1所述的放疗设备准直器校正方法，其特征在于，所述根据所述射线投影图像，从所述M个位置中确定出使所述准直器对准程度最高的目标位置包括：
    根据所述射线投影图像的灰度值和半影值，从所述M个位置中确定出使所述准直器对准程度最高的目标位置。
  3. 根据权利要求1所述的放疗设备准直器校正方法，其特征在于，所述根据所述射线投影图像，从所述M个位置中确定出使所述准直器对准程度最高的目标位置包括：
    根据所述射线投影图像，分别生成所述准直器移动至所述M个位置处时，所述射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中所述第二百分比＝(所述第一百分比+所述第三百分比)/2；
    分别计算所述准直器移动至所述M个位置处时所述射线投影图像的第二百分比剂量线与对应地理论第二百分比剂量线的相似度T；以及分别计算所述准直器移动至所述M个位置处时所述射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L；
    根据所述相似度T和所述距离L，确定所述目标位置。
  4. 根据权利要求3所述的放疗设备准直器校正方法，其特征在 于，所述根据所述射线投影图像，分别生成所述准直器移动至所述M个位置处时，所述射线投影图像的第一百分比、第二百分比、第三百分比剂量线包括：
    根据所述射线投影图像的灰度值，分别生成所述准直器移动至所述M个位置处时，所述射线投影图像的第一百分比、第二百分比、第三百分比剂量线。
  5. 根据权利要求3所述的放疗设备准直器校正方法，其特征在于，所述根据所述相似度T和所述距离L，确定所述目标位置包括：
    根据所述相似度T和所述距离L，计算所述准直器移动至所述M个位置处时所述射线投影图像对应的准直孔的对准参数q；
    对所述准直器移动至所述M个位置处时所述射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q；
    将所述M个位置中所述总对准参数Q最大的位置确定为所述目标位置。
  6. 根据权利要求1-5任一项所述的放疗设备准直器校正方法，其特征在于，所述放疗设备包括放射源、准直器，所述准直器上包括多个准直孔，所述放射源发出的射线通过所述多个准直孔聚焦至所述放疗设备等中心。
  7. 一种放疗设备准直器校正装置，其特征在于，包括：
    获取单元，用于分别获取所述准直器移动至M个位置处时，依次穿过所述准直器上的准直孔、放疗设备等中心平面之后的射线投影图像；所述M个位置包括：所述准直器设计位置以及与所述设计位置的位移差小于预设距离的至少一个其他位置；所述设计位置为：所述准直器对准的理论位置；
    确定单元，用于根据所述射线投影图像，从所述M个位置中确定出使所述准直器对准程度最高的目标位置；
    记录单元，用于记录所述目标位置对应的位置参数，以使得在利用所述放疗设备治疗时控制所述准直器移动至所述目标位置。
  8. 根据权利要求7所述的放疗设备准直器校正装置，其特征在 于，
    所述确定单元，具体用于根据所述射线投影图像的灰度值和半影值，从所述M个位置中确定出使所述准直器对准程度最高的目标位置。
  9. 根据权利要求7所述的放疗设备准直器校正装置，其特征在于，所述确定单元，具体包括：剂量线生成子单元、计算子单元以及确定子单元；
    所述剂量线生成子单元，用于根据所述射线投影图像，分别生成所述准直器移动至所述M个位置处时，所述射线投影图像的第一百分比、第二百分比、第三百分比剂量线，其中所述第二百分比＝(所述第一百分比+所述第三百分比)/2；
    所述计算子单元，用于分别计算所述准直器移动至所述M个位置处时所述射线投影图像的第二百分比剂量线与对应地理论第二百分比剂量线的相似度T；以及分别计算所述准直器移动至所述M个位置处时所述射线投影图像的第一百分比剂量线与第三百分比剂量线之间的距离L；
    所述确定子单元，用于根据所述相似度T和所述距离L，确定所述目标位置。
  10. 根据权利要求9所述的放疗设备准直器校正装置，其特征在于，
    所述剂量线生成子单元，具体用于根据所述射线投影图像的灰度值，分别生成所述准直器移动至所述M个位置处时，所述射线投影图像的第一百分比、第二百分比、第三百分比剂量线。
  11. 根据权利要求9所述的放疗设备准直器校正装置，其特征在于，
    所述确定子单元，具体用于根据所述相似度T和所述距离L，计算所述准直器移动至所述M个位置处时所述射线投影图像对应的准直孔的对准参数q；对所述准直器移动至所述M个位置处时所述射线投影图像对应的准直孔的对准参数q加权平均，计算总对准参数Q；将所述M个位置中所述总对准参数Q最大的位置确定为所述目标位 置。
  12. 根据权利要求7-11任一项所述的放疗设备准直器校正装置，其特征在于，所述放疗设备包括放射源、准直器，所述准直器上包括多个准直孔，所述放射源发出的射线通过所述多个准直孔聚焦至所述放疗设备等中心。
  13. 一种放疗设备准直器校正装置，其特征在于，包括：处理器、存储器、总线和通信接口；所述存储器用于存储计算机执行指令，所述处理器与所述存储器通过所述总线连接，当所述放疗设备准直器校正装置运行时，所述处理器执行所述存储器存储的所述计算机执行指令，以使所述放疗设备准直器校正装置执行如权利要求1-6中任一项所述的放疗设备准直器校正方法。
  14. 一种计算机存储介质，其特征在于，包括指令，当其在计算机上运行时，使得所述计算机执行如权利要求1-6中任一项所述的放疗设备准直器校正方法。
  15. 一种包含指令的计算机程序产品，其特征在于，当其在计算机上运行时，使得所述计算机执行如权利要求1-6中任一项所述的放疗设备准直器校正方法。
PCT/CN2018/099483 2018-08-08 2018-08-08 一种放疗设备准直器校正方法及装置 WO2020029148A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
PCT/CN2018/099483 WO2020029148A1 (zh) 2018-08-08 2018-08-08 一种放疗设备准直器校正方法及装置
CN201880008605.1A CN111010868B (zh) 2018-08-08 2018-08-08 一种放疗设备准直器校正方法及装置
US17/005,699 US11227700B2 (en) 2018-08-08 2020-08-28 Method and apparatus of correcting collimator of radiotherapy equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2018/099483 WO2020029148A1 (zh) 2018-08-08 2018-08-08 一种放疗设备准直器校正方法及装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US17/005,699 Continuation-In-Part US11227700B2 (en) 2018-08-08 2020-08-28 Method and apparatus of correcting collimator of radiotherapy equipment

Publications (1)

Publication Number Publication Date
WO2020029148A1 true WO2020029148A1 (zh) 2020-02-13

Family

ID=69413659

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/099483 WO2020029148A1 (zh) 2018-08-08 2018-08-08 一种放疗设备准直器校正方法及装置

Country Status (3)

Country Link
US (1) US11227700B2 (zh)
CN (1) CN111010868B (zh)
WO (1) WO2020029148A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021139088A1 (zh) * 2020-06-10 2021-07-15 上海西门子医疗器械有限公司 确定单槽准直板的目标位置的方法、装置和准直器组件
US11918829B2 (en) 2020-09-15 2024-03-05 Our United Corporation Method, controller and system for controlling dose in radiotherapy

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111710457A (zh) * 2020-06-29 2020-09-25 北京三强核力辐射工程技术有限公司 一种全身伽玛刀放射治疗用钴-60放射源及其制备方法
WO2022170596A1 (zh) * 2021-02-10 2022-08-18 西安大医集团股份有限公司 聚焦治疗头和医疗设备

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1919373A (zh) * 2005-08-25 2007-02-28 惠小兵 放射治疗装置
CN101927065A (zh) * 2009-01-16 2010-12-29 北卡罗来纳大学查珀尔希尔分校 用于癌症治疗和研究的紧凑型微束放疗***及方法
CN104586415A (zh) * 2013-10-31 2015-05-06 Ge医疗***环球技术有限公司 准直器对准偏差确定方法及计算机化断层成像***
US20160361567A1 (en) * 2015-06-12 2016-12-15 Accuray Incorporated Image-based aperture verification system for multi-leaf collimator
CN107041997A (zh) * 2016-02-05 2017-08-15 瓦里安医疗***国际股份公司 放射射束对准和放射射束测量的***、方法和装置
CN108186035A (zh) * 2018-01-02 2018-06-22 上海联影医疗科技有限公司 X射线成像***故障诊断方法、装置、***和存储介质

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102010041752B4 (de) 2010-09-30 2012-06-28 Siemens Aktiengesellschaft Kalibrierung eines Lamellenkollimators
RU2014154006A (ru) * 2012-06-05 2016-08-10 Конинклейке Филипс Н.В. Калибровка с декомпозицией на слои движения рентгеновских ст-томографов
CN203436706U (zh) * 2013-07-17 2014-02-19 官爱平 一种非等距聚焦放射装置
CN105288870B (zh) * 2015-11-03 2017-03-01 上海联影医疗科技有限公司 一种多叶准直器的校准方法
CN105476654B (zh) * 2016-01-04 2018-08-21 沈阳东软医疗***有限公司 一种上切片位置校正方法、装置及设备
US10314553B2 (en) * 2016-01-21 2019-06-11 FMI Medical Systems Co., Ltd. Focal spot position control using pre-patient collimator with beam tracking
WO2018093933A1 (en) * 2016-11-15 2018-05-24 Reflexion Medical, Inc. System for emission-guided high-energy photon delivery
CN106908457B (zh) * 2017-02-28 2019-10-15 赛诺威盛科技（北京）有限公司 基于实时跟踪x射线焦点位置的动态校准方法
CN107297031B (zh) * 2017-05-17 2021-05-28 上海交通大学 一种高精度放疗准直器
CN107800026B (zh) * 2017-10-27 2019-07-09 大族激光科技产业集团股份有限公司 一种激光器外光路准直的调试方法
CN108211134B (zh) * 2017-12-11 2021-01-12 上海联影医疗科技股份有限公司 多叶准直器初始化方法、计算机存储介质及放射治疗***

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1919373A (zh) * 2005-08-25 2007-02-28 惠小兵 放射治疗装置
CN101927065A (zh) * 2009-01-16 2010-12-29 北卡罗来纳大学查珀尔希尔分校 用于癌症治疗和研究的紧凑型微束放疗***及方法
CN104586415A (zh) * 2013-10-31 2015-05-06 Ge医疗***环球技术有限公司 准直器对准偏差确定方法及计算机化断层成像***
US20160361567A1 (en) * 2015-06-12 2016-12-15 Accuray Incorporated Image-based aperture verification system for multi-leaf collimator
CN107041997A (zh) * 2016-02-05 2017-08-15 瓦里安医疗***国际股份公司 放射射束对准和放射射束测量的***、方法和装置
CN108186035A (zh) * 2018-01-02 2018-06-22 上海联影医疗科技有限公司 X射线成像***故障诊断方法、装置、***和存储介质

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021139088A1 (zh) * 2020-06-10 2021-07-15 上海西门子医疗器械有限公司 确定单槽准直板的目标位置的方法、装置和准直器组件
EP4147641A4 (en) * 2020-06-10 2024-05-15 Siemens Shanghai Med Equip Ltd METHOD AND DEVICE FOR DETERMINING THE TARGET POSITION OF A SINGLE-SLOT COLLIMATION PLATE, AND COLLIMATOR ASSEMBLY
US11918829B2 (en) 2020-09-15 2024-03-05 Our United Corporation Method, controller and system for controlling dose in radiotherapy

Also Published As

Publication number Publication date
US11227700B2 (en) 2022-01-18
CN111010868B (zh) 2022-01-11
US20200395142A1 (en) 2020-12-17
CN111010868A (zh) 2020-04-14

Similar Documents

Publication Publication Date Title
WO2020029148A1 (zh) 一种放疗设备准直器校正方法及装置
US10369383B2 (en) Time-resolved pre-treatment portal dosimetry systems, devices, and methods
JP2022509306A (ja) イメージングにおける散乱評価および散乱補正を向上させるための方法および機器
US11103726B2 (en) Creating treatment field using initial field and patient specific geometry and achievable dose
US10806949B2 (en) Method and system of generating radiation treatment plan
WO2018090195A1 (zh) 一种放射治疗计划的生成方法和放射治疗计划***
US9889317B2 (en) System and method for automated radiation treatment planning using physical objectives
Nakano et al. Effect of setup error in the single‐isocenter technique on stereotactic radiosurgery for multiple brain metastases
JP2019136509A (ja) オーバーラップする輪郭への放射線量の最適化
US20200094073A1 (en) Methods to optimize coverage for multiple targets simultaneously for radiation treatments
Kim et al. Correlation analysis between 2D and quasi-3D gamma evaluations for both intensity-modulated radiation therapy and volumetric modulated arc therapy
JP2018515274A (ja) ビームジオメトリを選択する方法
Depuydt Proton therapy technology evolution in the clinic: impact on radiation protection
Tomida et al. Clinical usefulness of MLC s in robotic radiosurgery systems for prostate SBRT
US20150272497A1 (en) Methods, systems, and computer readable media for verifying the accuracy of medical treatment in accordance with a treatment plan
Wack et al. The impact of isocentric shifts on delivery accuracy during the irradiation of small cerebral targets—Quantification and possible corrections
Kang et al. Combination effects of tissue heterogeneity and geometric targeting error in stereotactic body radiotherapy for lung cancer using CyberKnife
Wegener et al. Implementing corrections of isocentric shifts for the stereotactic irradiation of cerebral targets: Clinical validation
Zhang et al. Feasibility study of real‐time planning for stereotactic radiosurgery
US11491349B2 (en) Patient irradiation treatment plan verification system and method
Xu et al. Effects of collimator angle, couch angle, and starting phase on motion‐tracking dynamic conformal arc therapy (4D DCAT)
Kutuzov et al. Verification of the delivered patient radiation dose for non‐coplanar beam therapy
Thomas et al. Local confidence limits for IMRT and VMAT techniques: a study based on TG119 test suite
Martens et al. : a new and effective off‐line correction protocol for rotational setup errors when using a robotic couch
Gourdeau et al. An EPID‐based method to determine mechanical deformations in a linear accelerator

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18929356

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18929356

Country of ref document: EP

Kind code of ref document: A1