Multifunctional radiotherapy calibration device, positioning system and calibration method

Abstract

The invention discloses a multifunctional radiotherapy calibration device, a positioning system and a calibration method.The multifunctional radiotherapy calibration device comprises a laser tracker target ball assembly, a calibration device body with supporting plate orthogonal scribed lines and a cubic die body with die body orthogonal scribed lines, and the calibration device body and the cubic die body are each provided with a plurality of target ball positioning holes; the target ball positioning holes in the cubic die body are respectively formed in the central positions of all surfaces of the cubic die body; the verification device body is provided with a surface positioning structure which is used for performing surface matching positioning with the cubic die body in the X direction, the Y direction and the Z direction, and a target ball center positioning hole is formed in the orthogonal point of the orthogonal scribed lines of the supporting plate. The method can realize the coincidence of the central point of a treatment area on a treatment bed board and the treatment central point of a beam port, the line width of a laser positioning system, the perpendicularity of orthogonal laser lines and the central point position of the laser positioning system, and the image guide range, geometric position relation and central point position of an image guide radiotherapy system. And quickly checking whether the axes of the two groups of X-ray beams are coplanar or not.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radiotherapy positioning technology, and simultaneously meets the position verification requirements of laser positioning systems, image-guided radiotherapy systems and patient support systems, and in particular relates to a multifunctional radiotherapy verification device, a positioning system and a verification method. BACKGROUND

[0002] Currently, particle radiotherapy equipment can be divided into proton radiotherapy equipment, heavy ion radiotherapy equipment and boron neutron capture therapy according to the type of particles.

[0003] Particle radiotherapy treatment rooms can be divided into isocentric treatment rooms and non-isocentric treatment rooms according to the layout of the room. Proton and heavy ion are usually isocentric treatment rooms, i.e. the centers of the laser positioning system, the image-guided radiotherapy system and the patient support system coincide. Non-isocentric treatment rooms are more common in boron neutron capture therapy devices. Considering the tolerance of the flat panel detector used in the image-guided radiotherapy system to superhot neutrons, the installation of the flat panel detector used in the image-guided radiotherapy system needs to be away from the beam port, so the center points of the laser positioning system, the image-guided radiotherapy system and the patient support system of the boron neutron capture therapy are usually non-isocentric.

[0004] The spatial positioning accuracy of the mechanical arm in the patient support system, the spatial positioning accuracy of the laser beam of the laser positioning system, the spatial accuracy of the tube beam in the image-guided radiotherapy system and the spatial accuracy of the detector installation all affect the position accuracy of the center points of the treatment room.

[0005] In order to realize the establishment and accurate adjustment of the position relationship of the center points, Chinese patent CN117398625A proposes a verification device for a laser lamp positioning system and a positioning method thereof. The method establishes the position relationship of the laser positioning line and the beam isocenter point through a laser tracker and a cubic phantom. The spatial position of the cubic phantom is adjusted through the six-dimensional adjustment device on the device to realize the laser lamp center and the beam isocenter.

[0006] However, the above technical solution has the following problems: first, the adjustment device is arranged on the bed body, which makes the verification process complex and affects the adjustment accuracy due to the operation errors of the verifier; second, the connection relationship structure of the cubic phantom and the device is complex and requires repeated operation, which affects the accuracy; third, it cannot simultaneously meet the verification requirements of isocentric treatment rooms and non-isocentric treatment rooms. SUMMARY

[0007] The purpose of this invention is to solve the problems of existing calibration devices, such as complex structure, low space utilization, complicated connection relationships, and low adjustment accuracy. It provides a multifunctional radiotherapy calibration device, positioning system, and calibration method. It uses a set of fixing devices to achieve rapid center position calibration of the patient support system, laser positioning system, and image-guided radiotherapy system in the treatment room to a certain extent, reducing the complicated device adjustment process and reducing system errors caused by differences in user operation. It can meet the calibration requirements in both isocentric and non-isocentric treatment rooms.

[0008] The technical solution adopted by this invention to achieve its first objective is as follows: a multifunctional radiotherapy calibration device, comprising a laser tracker target ball assembly, a calibration device body with orthogonal scribed lines on a support plate, and a cubic phantom with orthogonal scribed lines on a mold body. A plurality of target ball positioning holes are respectively provided on the calibration device body and the cubic phantom, wherein the target ball positioning holes on the cubic phantom are respectively located at the center of each face of the cubic phantom; the calibration device body is provided with a surface positioning structure for XYZ three-directional surface mating and positioning with the cubic phantom, and a target ball center positioning hole is provided at the orthogonal intersection of the orthogonal scribed lines on the support plate. This multifunctional radiotherapy calibration device, by providing a plurality of target ball positioning holes on the calibration device body and the cubic phantom, allows for the rapid insertion and positioning of the laser tracker target ball in the target ball positioning holes according to testing needs, ensuring the repeatability and accuracy of the laser tracker target ball base installation. When used in conjunction with a laser tracker, this device can quickly verify the coincidence of the center point of the treatment area on the treatment bed with the center point of the beam outlet; verify the linewidth and center point position of the laser positioning system; and quickly verify the image guidance range, geometric positional relationship, center point position, and whether the axes of the two X-ray beams are coplanar in the image-guided radiotherapy system. The use of this multifunctional radiotherapy verification device reduces the cumbersome device adjustment process and minimizes system errors caused by differences in user operation.

[0009] As a preferred option, the positioning hole at the center of the target ball ensures the accuracy of repeated assembly of the target ball base of the laser tracker.

[0010] Preferably, the laser tracker target ball assembly includes a laser tracker target ball base and a laser tracker target ball magnetically attached to the base. The laser tracker target ball base has a high-precision bottom positioning plane, with a base insertion post at the center of the positioning plane. The laser tracker target ball base allows for quick connection and positioning with the target ball positioning holes on the calibration device body and the cubic phantom, eliminating the need for position adjustment. This provides high positioning accuracy, convenient and quick operation, and precise installation and positioning of the laser tracker target ball, ensuring accurate repeatability between the laser tracker target ball and the calibration device body and cubic phantom.

[0011] Preferably, the cube mold has orthogonal engravings perpendicular to each other on its five faces: front, back, left, right, and top. Each orthogonal engraving has laser line width markings at both ends. The width of these laser line width markings is greater than the width of the orthogonal engravings and matches the width of the orthogonal engravings on the support plate of the calibration device body. Orthogonal engravings are drawn at the center of the five faces (front, back, left, right, and top) of the cube mold, and five laser tracker target ball assemblies can be installed inside the target ball positioning holes.

[0012] Preferably, the cubic phantom contains multiple tungsten metal spheres; the bottom of the cubic phantom has a positioning surface mounting structure, which includes a positioning ring. The cubic phantom needs to have good X-ray transmittance; therefore, it is generally made of organic polymer materials. When X-rays pass through the cubic phantom, the tungsten metal spheres leave a clear image on the detector, enabling verification of the image guidance range, geometric positional relationship, center point position, and whether the axes of the two X-ray beams are coplanar in the image-guided radiotherapy system. The bottom surface of the cubic phantom is designed with a high-precision dimensional positioning surface, ensuring the accuracy of repeated assembly of the cubic phantom on the phantom base plate.

[0013] Preferably, the device also includes a claw mechanism for adjusting the connection between the calibration device body and the treatment bed, the claw mechanism comprising a claw assembly. The claw mechanism connects the calibration device body and the treatment bed, ensuring their relative stability, and allows for adjustment of their relative positions as needed to meet different testing requirements, thereby satisfying the support needs of different radiotherapy patients.

[0014] The technical solution adopted by the present invention to achieve its second objective is: a multifunctional radiotherapy positioning system, characterized in that: it includes the aforementioned multifunctional radiotherapy calibration device, and further includes a patient support system, a laser positioning system and an image-guided radiotherapy system, wherein the multifunctional radiotherapy calibration device is installed on the treatment bed board of the patient support system.

[0015] The technical solution adopted by this invention to achieve its third objective is: a multifunctional radiotherapy positioning and verification method, which utilizes the aforementioned multifunctional radiotherapy verification device and includes the following steps: S1: Connect the calibration device body to the treatment bed board; S2: Select to set the number and position of the laser tracker target ball components separately according to the verification content, or select the number and position of the cubic phantom and the laser tracker target ball components; S3: Verify the patient support system, and / or laser positioning system, and / or image-guided radiotherapy system.

[0016] As a preferred embodiment, S21: Select at least three non-collinear support plate target ball base positioning holes, including the target ball center positioning hole, on the body of the calibration device, and simultaneously install the laser tracker target ball assembly to calibrate the center point of the patient support system.

[0017] As a preferred embodiment, S22: The cubic phantom is installed on the surface positioning structure of the calibration device body, and the laser tracker target ball assembly is installed in the target ball positioning holes on the YZ plane, XY plane, and XZ plane of the cubic phantom, respectively, so that they coincide with the theoretical values ​​of the X, Z, and Y axes of the positioning center point of the laser positioning system, and the laser positioning system is calibrated.

[0018] As a preferred embodiment, S23: The cubic phantom is installed on the surface positioning structure of the calibration device body, so that the target ball positioning holes on the YZ plane, XY plane and XZ plane at the center of the cubic phantom are respectively installed with the target ball components of the laser tracker, and so that they coincide with the theoretical values ​​of the X, Z and Y axes of the positioning center point of the laser positioning system, and the image-guided radiotherapy system is calibrated.

[0019] Furthermore, the method for verifying the patient support system includes the following steps: S311: Multi-point tracking measurement: Select three non-collinear support plate target ball base positioning holes on the calibration device body, including the target ball center positioning hole, and install the laser tracker target ball assembly respectively. S312: Use a laser tracker to collect multi-point coordinate information of the treatment bed board at any position, and use the multi-point information to calculate the position and orientation of the center point of the treatment area on the treatment bed board at that position. S313: Verify the accuracy performance requirements of bed surface position deviation, bed surface movement range, patient support device center rotation range, and lateral and rotational movement of the patient support device through data calculation results.

[0020] Furthermore, the verification steps for the bed surface position deviation in S313 include: automatically driving the treatment bed board to the preset position; using a laser tracker to read the coordinates of multiple laser tracker target spheres; using laser tracker data processing software, such as SA software, to automatically fit a plane formed by the coordinates of multiple laser tracker target spheres and obtain a measurement value (in addition to the automatically fitted plane data, the coordinate value of one target sphere also needs to be selected for position comparison. The fitted plane is used to obtain the normal vector of the bed board surface before and after movement, and further obtain the posture of the bed board. It is necessary to compare the position and posture of the bed before and after movement); comparing whether the measured value is consistent with the posture of the treatment bed board at the preset position, judging and adjusting (adjusting the motion coordinate system of the treatment bed board in the treatment room and motion compensation error) until the deviation is within the allowable range.

[0021] Furthermore, the verification steps for the range of motion of the bed surface in S313 include: moving the treatment bed board to the positive and negative limit positions in the X, Y, and Z directions by jogging, reading the coordinates of the target ball of the laser tracker for each individual laser tracker, automatically fitting (target ball displacement and displacement direction) using SA software, and calculating the positive and negative limit values ​​of the translation of the bed surface along the X, Y, and Z directions; comparing these values ​​with the design value of the range of motion of the bed surface (and confirming the consistency between the direction of movement of the treatment bed board and the X, Y, and Z directions of the treatment room coordinate system); if they are inconsistent, adjusting the patient support system until the range of translation of the bed surface is consistent with the design value.

[0022] Furthermore, the verification steps for the rotation range of the patient support system in S313 include: automatically driving the treatment bed board to the preset position of the treatment center point, using a laser tracker to read the coordinates of multiple laser tracker target balls respectively, and using SA software to automatically fit the plane formed by the coordinates of multiple laser tracker target balls; jogging the treatment bed board to rotate around the treatment center point until the treatment bed board is close to the wall, collecting the coordinates of multiple laser tracker target balls at this moment, and calculating the rotation angle of the bed board around the center point.

[0023] Furthermore, the step in S313 to verify the lateral movement accuracy of the patient support system includes: automatically driving the treatment bed board to a preset position, using a laser tracker to read the coordinates of multiple laser tracker target balls, and using SA software to automatically fit the plane formed by the coordinates of multiple laser tracker target balls; continuing to drive the treatment bed board to move along the X, Y, and Z directions respectively, and setting a certain distance for each movement, measuring the coordinates of multiple laser tracker target balls after each movement of the treatment bed board, calculating the interpolation of the actual pose change of the center point at each movement interval, and verifying that the lateral movement accuracy of the bed board is qualified if the error of each movement distance is within the allowable range.

[0024] Furthermore, the accuracy verification steps for rotational motion in S313 include: automatically driving the treatment bed to a preset position at the treatment center point; using a laser tracker to read the coordinates of multiple laser tracker target balls; using SA software to automatically fit the plane formed by the coordinates of multiple laser tracker target balls; continuing to drive the treatment bed to rotate around the treatment center point, and setting a certain angle for each rotation until the rotation range limit is reached; collecting the coordinates of multiple laser tracker target balls at that moment; and calculating the deviation between the rotation angle of the bed around the center point and the program-driven angle value.

[0025] Preferably, the laser positioning system verification method includes the following steps: S321: Install the cubic phantom on the surface positioning structure of the calibration device body, so that the axes of the target ball positioning holes on the YZ plane, XY plane, and XZ plane passing through the center of the cubic phantom are respectively in the same plane; S322: The robotic arm drives the treatment bed board to move the cubic model to the positioning center of the laser positioning system. Laser tracker target balls are installed in the target ball positioning holes on the YZ plane, XY plane, and XZ plane respectively, and are made to coincide with the theoretical values ​​of the X, Z, and Y axes of the positioning center point of the laser positioning system respectively. S323: Verify that each laser line falls in the middle of the laser line width marking scale line to confirm the laser positioning line width and laser positioning accuracy; when verifying the laser line width, use the support plate on the verification device body to orthogonally mark the laser line width and straightness to recheck the laser line width and straightness. The XZ plane laser line falls completely within the horizontal scale line, and the YZ plane laser line falls completely within the vertical scale line. S324: Align the laser line with the XOZ, YOZ, and XOY plane scale lines of the cubic phantom to confirm that the XOZ, YOZ, and XOY plane laser beams pass through the center point of the laser positioning system respectively.

[0026] Furthermore, the specific steps of S324 include: using the moving bed handle to slightly move the treatment bed board so that the Y-value of the laser tracker target ball is consistent with the Y-value of the center point of the laser positioning system; adjusting the XOZ plane laser beam to coincide with the XOZ plane scale line on the cubic phantom to prove that the XOZ plane laser beam passes through the center point of the laser positioning system; repeating the above operation to complete the verification that the YOZ and XOY plane laser beams pass through the center point of the laser positioning system.

[0027] Preferably, the method for verifying the image-guided radiotherapy system includes the following steps: S331: Install the cubic phantom on the surface positioning structure of the calibration device body, so that the axes of the target ball positioning holes on the YZ plane, XY plane, and XZ plane at the center of the cubic phantom are respectively in the same plane; S332: The robotic arm drives the treatment bed to move the cubic phantom to the positioning center of the image-guided radiotherapy system. Laser tracker target balls are installed in the target ball positioning holes on the YZ plane, XY plane, and XZ plane, respectively, and the X, Z, and Y coordinate values ​​of the target balls are made consistent with the X, Z, and Y values ​​of the center point of the laser-guided radiotherapy system. The target ball at the center of the cubic phantom is positioned to the center point of the image-guided radiotherapy system. Furthermore, S333 includes confirming the target guidance range of the image-guided radiotherapy system in the positive and negative X, Y, and Z directions.

[0028] Furthermore, the specific operational steps for confirming the target guidance range in the positive and negative X, Y, and Z directions include: S3331: Use the exposure function of the image-guided radiotherapy system to view the X-ray image of the cubic phantom in the image preview software, and check and adjust the tungsten metal sphere image in the positive and negative X-ray flat plate images to be consistent with the center point of the actual image-guided radiotherapy system. S3332: The treatment bed is moved along the positive X direction using a jog mode, and image registration is performed using the image registration function. After registration, the cube phantom can return to the center of the image-guided radiotherapy system. The treatment bed is moved further along the positive X direction by increasing the step size by a certain length, and image registration is performed again until the image registration function can no longer obtain accurate registration results. This confirms the positive X-direction target guidance range of the image-guided radiotherapy system. S3333: Similarly, confirm the negative target guidance range in the X direction; S3334: Repeat steps 1 to 3 above to confirm the target guidance range in the positive and negative Y direction and the positive and negative Z direction, respectively.

[0029] Furthermore, the accuracy of the positioning correction calculation was verified: after the treatment bed board was moved, the distance of movement of the treatment bed board was recorded, and positioning correction calculation was performed using image registration software. The deviation between the actual bed movement distance and the positioning correction calculation data was compared. The deviation was within the deviation of the system design, which verified the accuracy of the positioning correction calculation.

[0030] Furthermore, the repeatability of the setup calibration was verified: the operation to verify the accuracy of the setup correction calculation was repeated 10 times, and the deviation values ​​of the 10 calculation results were compared. The data repeatability was within the range of the system design, which verified the repeatability of the setup calibration.

[0031] The technical solution adopted by this invention to achieve the fourth objective is: a method for verifying the accuracy of patient positioning in a non-isocentric treatment room, which utilizes the aforementioned multifunctional radiotherapy verification device to verify the accuracy of patient positioning in a non-isocentric treatment room; the verification method includes the following steps: S1: Pre-calibrate the patient treatment system, laser positioning system, and image-guided radiotherapy system in the non-isocentric treatment room; S2: The robotic arm moves the treatment bed board to the center point of the laser positioning system, so that the scale lines on the cube phantom are aligned with the corresponding laser lines of the laser positioning system. The marked points on the cube phantom coincide with the center point of the laser positioning system, thereby obtaining the first positioning deviation of the cube phantom relative to the laser positioning system. S3: The robotic arm moves the treatment bed to the center point of the image-guided radiotherapy system; the image-guided radiotherapy system is used to photograph the phantom, confirming that the phantom's marker point is located in the center of the obtained image, and the image registration software is used to perform registration calculations on the obtained image to obtain the second positional deviation of the phantom relative to the image-guided radiotherapy system. S4: The robotic arm moves the treatment bed board to the center point of the treatment beam; the position of the marked point on the cubic phantom is corrected according to the first and second positioning deviations; S5: Calculate the coordinates of the current cubic phantom marker point. If the coordinates are consistent with the coordinates of the beam center point of the treatment position, then the radiotherapy positioning system of the non-isocentric treatment room is accurate.

[0032] The beneficial effects of this invention are as follows: When used in conjunction with a laser tracker, this multifunctional radiotherapy calibration device, positioning system, and calibration method can quickly verify the deviation of the patient support system bed surface position, the range of bed surface translational movement, the isocentric rotation range of the treatment bed board, the accuracy of lateral movement of the bed board, and the precision of rotational movement of the treatment bed board. It can also quickly verify the coincidence of the center point of the treatment area on the treatment bed board with the treatment center point of the beam port; verify the linewidth, perpendicularity of the orthogonal laser lines, and center point position of the laser positioning system; and quickly verify the image guidance range, geometric positional relationship, center point position, and whether the axes of the two X-ray beams are coplanar in the image-guided radiotherapy system. The use of this multifunctional radiotherapy calibration device reduces the complex device adjustment process and minimizes system errors caused by differences in user operation. It can simultaneously meet the center calibration requirements in both isocentric and non-isocentric treatment rooms. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of the multifunctional radiotherapy calibration device of the present invention.

[0034] Figure 2 This is an exploded structural diagram of the multifunctional radiotherapy calibration device of the present invention.

[0035] Figure 3 This is a partial structural schematic diagram of the multifunctional radiotherapy calibration device of the present invention.

[0036] Figure 4 This is a schematic diagram of a laser tracker target ball assembly in this invention.

[0037] Figure 5 This is a schematic diagram of a cubic phantom in this invention.

[0038] Figure 6 This is a schematic diagram showing the distribution of positioning holes on the main body of the verification device in this invention.

[0039] Figure 7 This is a schematic diagram showing the distribution of positioning holes on the cubic mold body of the present invention.

[0040] Figure 8 This is a schematic diagram of the combined structure of the multifunctional radiotherapy calibration device of the present invention.

[0041] Figure 9 This is a structural schematic diagram of the multifunctional radiotherapy calibration device assembly of the present invention from another angle.

[0042] Figure 10 This is an exploded structural diagram of the multifunctional radiotherapy calibration device assembly of the present invention.

[0043] Figure 11 This is a top view of the multifunctional radiotherapy calibration device assembly of the present invention.

[0044] Figure 12 yes Figure 11 Sectional view of AA.

[0045] Figure 13 yes Figure 11 BB section view.

[0046] Figure 14 This is a schematic diagram of the connection between the multifunctional radiotherapy calibration device of the present invention and the treatment bed board.

[0047] Figure 15 This is a schematic diagram of an application structure in Embodiment 3 of the present invention.

[0048] Figure 16 , Figure 17 This is a schematic diagram of the application structure of Embodiment 4 of the present invention.

[0049] Figure 18 , Figure 19 , Figure 20 This is a schematic diagram of the structure of the cubic phantom (with built-in tungsten metal spheres) and the phantom base plate in this invention, showing X-ray penetration.

[0050] Figure 21 This is a schematic diagram of the flat panel imaging results of the X-ray negative detector in Example 5.

[0051] Figure 22 This is a perspective view of the laser tracking target ball assembly in this invention.

[0052] Figure 23 This is a diagram showing the imaging geometry between the flat panel detector and the X-ray tube in the positive and negative X directions in Example 5.

[0053] Figure 24 This is a schematic diagram of the multifunctional radiotherapy positioning system of the present invention.

[0054] Figure 25 This is a top view of the cubic model in this invention.

[0055] Figure 26 yes Figure 25 DD section view.

[0056] Figure 27 yes Figure 25EE section view (rotated).

[0057] Figure 28 yes Figure 25 FF section view (rotated).

[0058] In the figure: 1. Support plate, 11. Positioning hole of target ball base of support plate, 12. Orthogonal scale line of support plate, 121. Horizontal scale line of support plate, 122. Longitudinal scale line of support plate, 13. Positioning slot of bottom plate, 14. Support platform of mold bottom plate, 15. Fastening hole of bottom plate, 16. Fastener, 17. Snap-fit ​​positioning hole; 2. Mold base plate; 21. Target ball base positioning surface; 22. Mold insert groove; 23. Mold slot; 24. Target ball center positioning hole. 3. Cubic phantom body; 31. Positioning ring; 32. Orthogonal engraving lines on the phantom body; 33. Positioning hole on the target ball base of the phantom body; 34. Positioning surface of the phantom body; 35. Laser line width marking scale line; 36. Tungsten metal ball. 4. Laser tracker target ball base; 41. Base body; 42. Target ball receiving groove; 43. Slot; 44. Magnet; 45. Hole elastic retaining ring; 46. Base insertion post. 5. Laser tracker target ball; 6. Puller mechanism; 7. Pull claw assembly; 71. Pull claw body; 72. Locking screw handle; 73. Nylon strip; 8. Locking strip assembly; 81. Positioning locking strip; 82. Positioning pin; 83. Nylon stop; 84. Locking hole; 10. Treatment bed board; 101. Treatment bed board positioning protrusion; 100. Calibration device body; 200. Surface positioning structure; 300. Treatment room; 400. Patient support system; 500. Laser positioning system; 501. Center point of laser positioning system; 600. Image-guided radiotherapy system; 601. Center point of image-guided radiotherapy system; 602. Detector; 603. X-ray tube; 700. Treatment center point of beam port; 800. Center point of treatment area on treatment bed. 20. Laser line, 30. X-ray, 40. Robotic arm. Detailed Implementation

[0059] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0060] Example 1: exist Figure 1 , Figure 2 , Figure 3 In the embodiment shown, a multifunctional radiotherapy calibration device is used for rapid confirmation of the spatial center point for radiotherapy, and can simultaneously calibrate the center points of the laser positioning system, the image-guided radiotherapy system, and the patient support system.

[0061] The multifunctional radiotherapy calibration device includes a laser tracker target ball assembly, a calibration device body 100 with orthogonal scribe lines, and a cubic phantom 3 with orthogonal scribe lines. A plurality of target ball positioning holes are respectively provided on the calibration device body 100 and the cubic phantom 3, wherein the target ball positioning holes on the cubic phantom are located at the center of each face of the cubic phantom; a central positioning structure is provided at the center of the orthogonal scribe lines on the calibration device body 100. The central positioning structure includes a surface positioning structure 200 for XYZ three-directional surface positioning with the cubic phantom 3 and a target ball central positioning hole 24.

[0062] The target ball positioning holes include a support plate target ball base positioning hole 11 provided on the body of the calibration device and a mold target ball base positioning hole 33 provided on the cubic mold 3.

[0063] The support plate orthogonal scale line 12 provided on the body 100 of the calibration device includes a horizontal scale line 121 and a vertical scale line 122. A surface positioning structure for mounting a cubic mold is provided at the orthogonal center of the support plate orthogonal scale line 12. A target ball center positioning hole 24 is provided at the orthogonal center position.

[0064] The calibration device body 100 includes a support plate 1 for movable and adjustable connection with the treatment bed board 10, a phantom base plate 2, a cubic phantom 3, and a laser tracker target ball assembly disposed on the support plate 1. Specifically, equidistant treatment bed board positioning protrusions 101 can be provided on the treatment bed board to achieve equidistant movable positioning of the calibration device body and the treatment bed board; of course, any positioning method can also be used.

[0065] The laser tracker target ball assembly includes a laser tracker target ball base 4 and a laser tracker target ball 5 disposed on the laser tracker target ball base 4.

[0066] like Figure 5As shown, the cube mold 3 has two sets of large, mutually perpendicular scale lines on its five surfaces: front, back, left, right, and top. The perpendicular intersection of the two sets of large scale lines is the center point of the plane on which the cube mold is located. The large scale lines are defined as orthogonal scale lines 32 of the mold. A positioning hole 33 for the target ball base of the mold is provided at the center point. At both ends of each large scale line, there are small scales marking the width of the laser line, defined as laser line width marking scale lines 35. During the processing of the cube mold 3, the center point of the positioning hole for the target ball base of the cube mold is ensured to coincide with the large scale line. This coincidence establishes the relationship between the large scale line and the measurement value of the target ball of the laser tracker. During calibration, each laser line is checked to ensure that it falls in the middle of the small scale line, thereby confirming the width of the laser positioning line and the accuracy of laser positioning. The width of the laser line width marking scale line 35 is greater than the width of the orthogonal scale line 32 of the mold and is consistent with the width of the orthogonal scale line on the support plate of the calibration device body. The bottom of the cubic mold body 3 is provided with a positioning surface mounting structure, which includes the bottom surface of the cubic mold body and a raised or recessed positioning surface provided on the bottom surface.

[0067] See Figure 1 Meanwhile, the support plate 1 is provided with two scale lines, one horizontal and one vertical, which are defined as the support plate orthogonal scale lines 12. The support plate orthogonal scale lines 12 include the support plate horizontal scale line 121 and the support plate vertical scale line 122. The width of the scale line is consistent with the spacing of the small scale lines on the cubic mold 3. When checking the laser line width, the support plate orthogonal scale lines 12 are used to check the laser line width and straightness. The XZ plane laser line falls completely within the support plate horizontal scale line 121, and the YZ plane laser line falls completely within the support plate vertical scale line 122.

[0068] The support plate 1 is made of metal and has multiple positioning holes 11 for mounting the laser tracker target ball base 4, ensuring the repeatability and accuracy of the laser tracker target ball base 4. The position and number of the positioning holes 11 are set according to the testing requirements.

[0069] In this embodiment, the support plate 1 is a cuboid plate. A bottom plate positioning slot 13 is provided on the surface of the support plate 1 along the orthogonal engraving line 12. The bottom plate positioning slot 13 is recessed on the support plate 1 and passes through the upper and lower surfaces of the support plate 1. A mold base plate support platform 14 is provided inside the bottom plate positioning slot 13 to support the mold base plate 2. A bottom plate fastening hole 15 is provided on the mold base plate support platform 14 to realize the fixed connection between the mold base plate 2 and the mold base plate support platform 14.

[0070] The base plate positioning slot 13, the base plate support platform 14, and the base plate fastening hole 15 facilitate the installation and positioning of the base plate 2.

[0071] When it is necessary to set up cubic molds 3 of different sizes, the positioning and connection of cubic molds 3 of different sizes can be achieved by replacing the body of the calibration device. Replacing the body of the calibration device is mainly used to replace the surface positioning structure of the cubic mold on the mold base plate 2. The surface positioning structure is a groove-shaped or protruding XYZ three-directional surface positioning structure.

[0072] The mold base plate 2 is embedded in the positioning slot 13 of the base plate and is fastened to the mold base plate support platform 14 by fasteners 16.

[0073] The support plate 1 is also provided with a snap-fit ​​positioning hole 17 for snap-fit ​​positioning of the card strip assembly. In another embodiment, a card strip groove adapted to the card strip can also be provided on the lower plate surface of the support plate 1, and direct snap-fit ​​positioning with the card strip can be achieved through the card strip groove.

[0074] The base plate 2 of the phantom is made of organic polymer material, which has good X-ray transmittance. It has a high-precision target ball base positioning surface 21 at the center position to ensure the repeatability and accuracy of the laser tracker target ball base assembly.

[0075] In this embodiment, a surface positioning structure is provided at the center of the mold base plate 2. The surface positioning structure includes a groove-shaped positioning surface structure, specifically including a mold insert groove 22 and a mold slot 23. In this embodiment, the positioning surface mounting structure of the cubic mold 3 includes the bottom surface of the cubic mold and a raised positioning surface provided on the bottom surface. Specifically, a positioning ring 31 is provided below the cubic mold 3. The positioning surface 34 is formed by the side of the positioning ring 31 and the bottom surface of the cubic mold for positioning. In use, the cubic mold 3 is embedded in the mold insert groove 22 and cooperates with the bottom surface of the groove. The positioning ring cooperates with the side of the mold slot to achieve positioning in the XYZ three directions. A target ball center positioning hole 24 is provided at the center of the target ball base positioning surface 21. The target ball center positioning hole 24 allows for easy direct insertion and installation of the laser tracker target ball base 4 on the mold base plate 2, achieving high-precision positioning.

[0076] like Figure 6 As shown, in this embodiment, 12 support plate target ball base positioning holes 11 are distributed on the verification device body formed by the support plate 1 and the mold base plate 2. These holes are respectively located at one end of the support plate near the mold base plate and along the X-direction. Positioning hole No. Positioning hole number and Location number, among which The positioning hole is set on the longitudinal scale line 122 of the support plate.

[0077] A setting is provided on the horizontal scale line 121 of the support plate Positioning hole number and Positioning hole number 1, in which The positioning hole is located at the center of the perpendicular intersection of the horizontal scale line 121 and the vertical scale line 122 of the support plate, that is, at the center of the mold base plate 2. Positioning hole number 24 is the center positioning hole of the target ball.

[0078] Two sets of support plate target ball base positioning holes 11 are provided on the support plate 1 on the other side of the base plate 2, respectively. Positioning hole No. Positioning hole number and Positioning hole number 1 Positioning hole No. Positioning holes and Positioning hole number 1, in which Number and The positioning hole is set on the longitudinal scale line 122 of the support plate.

[0079] The cubic mold 3 is a detachable and replaceable component, and different specifications of cubic mold 3 can be replaced as needed.

[0080] like Figure 7 As shown, in this embodiment, the five target ball base positioning holes 33 on the front, back, left, right, and top of the cubic model are respectively defined as... Positioning hole No. Positioning hole No. Positioning hole No. Positioning hole number and Positioning hole number 1, in which Positioning hole No. 1 and The positioning holes are set on the same axis.

[0081] The cubic mold 3 and the mold base plate 2 are fitted together via positioning surfaces. The bottom surface of the cubic mold 3 and the side surface of the positioning ring 31 are both mold positioning surfaces 34, which have high-precision dimensions and can ensure the accuracy of repeated assembly on the mold base plate 2. The cubic mold 3 and the mold base plate 2 are installed through positioning surfaces in the X, Z, and Y directions. After installation, the axes of the target ball base positioning holes on the YZ plane, XY plane, and XZ plane at the center of the cubic mold are all in the same plane, with deviation values ​​far lower than the accuracy requirements of the laser positioning line position.

[0082] The cubic phantom 3 is made of an organic polymer material and has good X-ray permeability. Multiple tungsten metal spheres 36 are disposed inside the cubic phantom 3. See also... Figures 25-28In this embodiment, five tungsten metal spheres are arranged inside the cubic phantom 3. When X-rays pass through the cubic phantom, the tungsten metal spheres can leave a clear image on the detector.

[0083] The laser tracker target ball base 4 is inserted into the positioning holes 33 of the five target ball bases of the phantom body, and the laser tracker target ball is installed on the laser tracker target ball base 4.

[0084] The laser tracker target ball base 4 is installed on the support plate 1 and the cubic mold 3 to ensure the repeatability of the laser tracker target ball 5 with the support plate and the cubic mold.

[0085] like Figure 4 As shown, the laser tracker target ball base 4 includes a base body 41. A target ball receiving groove 42 is provided at the bottom of the base body 41. A slot 43 is provided inside the target ball receiving groove 42. A magnetic suction component for adsorbing the laser tracker target ball 5 is provided inside the target ball receiving groove 42. The magnetic suction component includes a magnet 44 disposed inside the target ball receiving groove 42 and an elastic retaining ring 45 for the hole. The magnet 44 is limited inside the target ball receiving groove 42 by the elastic retaining ring 45 for the hole, which is located inside the slot 43. The magnet 44 provides magnetic attraction but does not directly contact the target ball. The target ball is magnetically attracted and positioned on the target ball receiving groove 42 formed by three small quadrilateral curved surfaces. The laser tracker target ball 5 is attracted inside the target ball receiving groove 42 by the magnet 44. A base insertion post 46 is provided at the bottom of the base body 41 for quick insertion and connection with the target ball base positioning hole 11 on the support plate and the target ball base positioning hole 33 on the cubic mold body.

[0086] The support plate 1 is movably connected to the treatment bed board 10 via multiple sets of pull claw mechanisms 6. The screw handles 72 on the pull claw mechanisms 6 are tightened and press against the support plate 1 and the treatment bed board to ensure their relative stability.

[0087] The pull claw mechanism 6 includes a pull claw assembly 7 and a locking strip assembly 8. The pull claw assembly 7 includes a pull claw body 71 and a locking screw handle 72 disposed on the pull claw body 71. A locking strip mounting hole 73 is provided on the pull claw body 71, and a nylon strip 73 is disposed inside the pull claw body 71. The nylon strip 73 is used for positioning and engagement with the underside of the treatment bed surface during use, and also has a shock-absorbing function, ensuring the stability of the entire device during use. The pull claw body 71 has a U-shaped structure and is arranged laterally.

[0088] See Figure 14In use, the pull claw assembly 7 works in conjunction with the locking strip assembly 8 for connecting the treatment bed board. The locking strip assembly 8 includes a positioning locking strip 81 and a positioning pin 82 disposed on the positioning locking strip 81. The positioning locking strip 81 has standard dimensions and repeatability accuracy, and is used to achieve locking and positioning with the treatment bed board. The positioning pin 82 is used to achieve locking and positioning with the support plate. Nylon blocks 83 are provided at both ends of the positioning locking strip 81. The nylon blocks 83 are provided with block positioning holes 84. The two nylon blocks 83 and the positioning locking strip 81 form a U-shaped locking structure. In use, the locking strip is horizontally positioned above the treatment bed board. The two nylon blocks 83 cooperate with the two sides of the treatment bed board. At the same time, the block positioning holes 84 cooperate with the treatment bed board positioning protrusion 101 on the treatment bed board to limit the movement, achieving a limiting cooperation with the treatment bed board and ensuring that the support plate 1 does not move laterally relative to the treatment bed board.

[0089] In another embodiment, the pull claw mechanism can also adopt other mechanical locking mechanisms, such as a mechanical buckle structure, which can also achieve quick locking of the support plate and the treatment bed board, ensuring the relative stability of the support plate and the bed board.

[0090] See Figures 8-13 This multifunctional radiotherapy calibration device is widely applicable to various existing particle radiotherapy scenarios, including but not limited to proton and heavy ion radiotherapy and boron neutron capture therapy. It can be used by directly mounting a laser tracker target ball assembly on the calibration device itself, or it can be used in conjunction with a cubic phantom. It can be used with one or multiple laser tracker target ball assemblies, depending on the specific requirements.

[0091] See Figure 14 This is a schematic diagram of the structure of a multifunctional radiotherapy calibration device used in conjunction with a treatment bed.

[0092] The patient support system includes a treatment bed 10 and a robotic arm 40. Since the treatment bed 10 is an important component of the radiotherapy patient support system, it is usually made of carbon fiber material. The treatment bed 10 achieves six degrees of freedom of movement through the robotic arm, namely translation along the X, Y, and Z directions and rotation along the X, Y, and Z directions.

[0093] In use, first install two sets of positioning clips 81 on the treatment bed board 10, then install the support plate 1 on the positioning clips, and use the corresponding snap-fit ​​positioning holes 17 and positioning pins 82 for positioning; select the required mold base plate 2 and embed the mold base plate 2 into the base plate positioning slot 13, and fasten the mold base plate 2 to the base plate fastening hole 15 on the mold base plate support platform 14 with fasteners 16 to achieve the connection between the mold base plate 2 and the support plate 1. Move the support plate to the required position along the treatment bed board, then snap the pull claw body 71 into the support plate and the outer edge of the treatment bed board, and lock the support plate, clips, and treatment bed board into one unit from top to bottom using the locking screw handle 72 to achieve the positioning of the relative position of the support plate and the treatment bed board. A cubic mold or a laser tracker target ball assembly can then be set on the mold base plate 2 as needed.

[0094] The support plate 1 is indirectly positioned on the treatment bed board via positioning clips 81. These clips can be selectively positioned at the desired location using positioning structures on both sides of the treatment bed board, thus enabling the support plate 1 to be movable along the bed board. Since boron neutron capture therapy requires the patient to be positioned near the edge of the treatment bed board, the treatment area on the treatment bed board is selected in the extended area at the end of the bed board, where a head and neck support will be added later. The support plate is positioned by the clips and securely fastened to the treatment bed board using four claw assemblies on both sides, allowing for the movable installation of the support plate 1 along the bed board. ~ The positioning holes of the target ball base of the support plate, the base plate of the mold, and the cubic mold are located within the treatment area of ​​the treatment bed plate extension to meet the various verification and usage requirements involved in this patent.

[0095] The positioning pins 82 on the support plate 1 and the positioning clip 81 work together to ensure that there is no repeated assembly error between the support plate and the treatment bed. Although the base plate 2 and the support plate 1 are made of different materials, when machining the center positioning hole 24 of the target ball, the base plate 2 and the support plate are fixed with fasteners 16 before machining, and the fasteners 16 are not removed after machining. This ensures that during repeated disassembly and disassembly of the device, the laser tracker target ball on the center positioning hole 24 is always at the center point of the treatment area on the treatment bed.

[0096] The structural design of the laser tracker target ball base 4 ensures that after the laser tracker target ball 5 is installed on the laser tracker target ball base 4, the center of the laser tracker target ball and the mounting surface of the laser tracker target ball base 4 are coaxial and have a fixed axial dimension deviation. The axial coordinate of the laser tracker target ball 5, after adding this deviation, becomes the spatial coordinate value of the point on the support plate surface.

[0097] This multifunctional radiotherapy calibration device can meet the requirements for testing patient support systems in the standard YY / T1763-2021 Performance Characteristics of Medical Electrical Equipment and Medical Light Ion Beam Equipment.

[0098] It can meet the usage requirements for testing laser positioning line width and laser positioning accuracy in "YY / T 1537-2017 Performance and Test Methods for Laser Positioning Systems for Radiotherapy".

[0099] It can meet the various testing requirements for the gold standard registration mode in "YY 1650-2019 Performance and Test Methods of X-ray Image-Guided Radiotherapy Equipment", including target guidance range, accuracy of positioning correction calculation, and repeatability of positioning calibration.

[0100] Example 2: like Figure 24 As shown, a multifunctional radiotherapy positioning system includes the multifunctional radiotherapy calibration device described in Embodiment 1, and further includes a patient support system 400, a laser positioning system 500, and an image-guided radiotherapy system 600. The multifunctional radiotherapy calibration device is mounted on the treatment bed 10 of the patient support system 400. The patient support system 400 includes the treatment bed 10 and a robotic arm 40. The image-guided radiotherapy system 600 includes two sets of detectors 602 and two sets of X-ray tubes 603.

[0101] The laser positioning system 500 uses non-divergent visible light to form three orthogonal laser beam sectors within the treatment room (see [link]). Figure 17 The three orthogonal laser beams intersect at a single point, which is the center point 501 of the laser positioning system.

[0102] The image-guided radiotherapy system consists of two X-ray tubes 603 and a detector 602. The central axes of the beams of the two X-ray tubes are coplanar and perpendicular, and the intersection of the central axes of the beams is the center point 601 of the image-guided radiotherapy system.

[0103] The patient support system allows for translation and rotation of the bed surface along the X, Y, and Z directions, with its center point at 80° to the center of the treatment area on the treatment bed. The beam center point is typically the geometric center within the range that the particle beam can encompass.

[0104] The spatial positioning accuracy of the robotic arm in the patient support system, the spatial positioning accuracy of the laser beam in the laser positioning system, the spatial accuracy of the X-ray tube beam in the image-guided radiotherapy system, and the spatial accuracy of the detector installation all affect the positional accuracy of each center point in the treatment room.

[0105] When used in conjunction with a laser tracker, the calibration device body is used... The target ball at position 800 can quickly align the center point 800 of the treatment area on the treatment bed with the center point 700 of the beam port treatment. Verify the line width, perpendicularity of orthogonal laser lines, and position of the center point of the laser positioning system. A rapid verification was performed on the geometric positional relationship, center point position, and whether the axes of the two X-ray beams were coplanar in the image-guided radiotherapy system.

[0106] To a certain extent, it enables rapid centering calibration of the patient support system, laser positioning system, and image-guided radiotherapy system in the treatment room, reducing the complicated device adjustment process and minimizing system errors caused by differences in user operation.

[0107] Example 3: See Figures 15-24 Figure 400 illustrates a multifunctional radiotherapy calibration method that can simultaneously calibrate the center points of a laser positioning system, an image-guided radiotherapy system, and a patient support system. Applicable scenarios include various existing particle radiotherapy methods, including proton and heavy ion radiotherapy and boron neutron capture therapy. The treatment room of a particle radiotherapy device typically includes a laser positioning system 500, an image-guided radiotherapy system 600, and a patient support system 400 to confirm the location of the patient's tumor target.

[0108] The calibration method for this multifunctional radiotherapy system, utilizing the multifunctional radiotherapy calibration device described in Example 1, includes the following steps: S1: Connect the calibration device body 100 to the treatment bed board 10; S2: Select to set the number and position of the laser tracker target ball components separately according to the verification content, or select the number and position of the cubic phantom and the laser tracker target ball components; S3: Verify the patient support system, and / or laser positioning system, and / or image-guided radiotherapy system.

[0109] Example 4: exist Figure 15 In the illustrated embodiment, a method for verifying a patient support system includes the following steps: Step 1: During measurement, first position the support plate 1 on the treatment bed board 10 using the positioning clip 81, and then fix it using the pull claw assemblies 7 on both sides.

[0110] Step 2: Use multi-point tracking measurement: Select the point containing on the support plate. The three non-collinear positioning holes 11 of the target ball base of the support plate are used to install the laser tracker target ball base 4 and the laser tracker target ball 5, respectively, to achieve multi-point tracking measurement. Preferably, in this embodiment, the target ball base 4 and the laser tracker target ball 5 are respectively installed in the three non-collinear positioning holes 11 of the target ball base of the support plate. , , , , The laser tracker target ball 5 is installed in the positioning hole 11 of the target ball base of the support plate.

[0111] To define the attitude of a moving object in space, it is usually necessary to define a point on the object and its spatial vector. In actual measurement, it is often necessary to simultaneously measure three non-collinear points on the object's surface to determine the coordinates of a point on the object and its spatial vector.

[0112] To eliminate measurement errors introduced by a single data error during the measurement process, this device, when in use, uses a support plate... , , , , The positioning hole 11 of the support plate target ball base simultaneously installs 5 laser tracker target ball bases 4 and laser tracker target balls 5. Even if one of the laser tracker target balls 5 is blocked or the data is inaccurate during measurement, it can be easily detected and removed when processing the data.

[0113] Step 3: Quickly check whether the bed surface position deviation is within the allowable range: The robotic arm moves the treatment bed to the preset position. A laser tracker reads the coordinates of five target spheres. Laser tracker measurement software, such as SA software, automatically fits the plane formed by the coordinates of the five target spheres to determine the position. Using the coordinates of the laser tracker target ball at the location as a reference point, the spatial normal vector of the plane is fitted to further determine the pose of the treatment bed board.

[0114] Compare the position of the fixed treatment bed board with its position at the preset point. If they are inconsistent, check if the position is within the system's allowable deviation. If the deviation exceeds the allowable deviation, the patient support system needs to be recalibrated.

[0115] Step 4: Confirm whether the range of bed surface translation movement is consistent with the design value: The robotic arm moves the treatment bed 10 to the positive and negative limit positions in the X, Y, and Z directions, respectively. The coordinates of the five laser tracker target spheres are read using a laser tracker. SA software is then used to automatically fit the plane formed by the coordinates of the five laser tracker target spheres to determine the position. The target ball coordinates of the laser tracker are centered at the center point.

[0116] Calculate the positive and negative limits of the bed surface translation along the X, Y, and Z directions. Compare these values ​​with the design values ​​for the bed surface's range of motion to confirm whether the range of motion matches the design values.

[0117] Step 5: Quickly measure the rotation range of the treatment bed board at the center: The robotic arm moves the treatment bed to a preset position, which can typically be used. At target point number 1, the coordinates of the target ball from five laser trackers were read. SA software was then used to automatically fit a plane formed by these five laser tracker target ball coordinates to determine the position. The target ball coordinates of the laser tracker are centered at the center point.

[0118] The robotic arm rotates the treatment bed board around a preset point until the treatment bed board is close to the wall. At this moment, the coordinates of five laser tracker target balls are collected, and the rotation angle of the bed board around the center point is calculated. The isocentric rotation range of the treatment bed board is quickly measured.

[0119] Step 6: Verify the accuracy of the lateral movement of the bed board: The robotic arm moves the treatment bed to the preset position. A laser tracker reads the coordinates of five target spheres. SA software automatically fits the plane formed by the coordinates of the five target spheres to determine the position. The target ball coordinates of the laser tracker are centered at the center point.

[0120] The robotic arm drives the treatment bed board to move along the X, Y, and Z directions respectively, and the distance of each movement is set to 100mm. The coordinates of the five laser tracker target balls are measured after each movement of the treatment bed board. The interpolation value of the actual pose change of the center point at each movement interval is calculated. If the error of each movement distance is within the allowable range, the accuracy of the lateral movement of the bed board is verified as qualified.

[0121] Step 7: Quickly verify the accuracy of the rotational movement of the treatment bed board: The robotic arm moves the treatment bed to the preset position. A laser tracker reads the coordinates of five target spheres. SA software automatically fits the plane formed by the coordinates of the five target spheres to determine the position. The coordinates of the laser tracker target ball at the reference point are .

[0122] Location The target ball point serves as a reference point on the treatment bed board during the testing process. This point can be used only when the position of the treatment bed board needs to be measured, such as in tests of the translation range and accuracy of the treatment bed board. When the posture of the treatment bed board needs to be obtained, the other four target ball points are required to construct a fitting plane together, thereby calculating the position. The posture.

[0123] The robotic arm drives the treatment bed to rotate around the treatment center point, with each rotation angle set at 5° until the rotation range limit is reached. At that moment, the coordinates of five laser tracker target balls are collected, and the deviation between the bed's rotation angle around the center point and the programmed angle value is calculated. This allows for rapid verification of the treatment bed's rotational motion accuracy.

[0124] This allows for rapid verification of the patient support system's bed surface position deviation, bed surface translation range, treatment bed board isocenter rotation range, bed board lateral movement accuracy, and treatment bed board rotation accuracy. It also enables rapid verification of the coincidence between the treatment area center point 800 and the beam port treatment center point 700 on the treatment bed board. Using this device for rapid center position calibration reduces the complexity of the device verification process, minimizes system errors caused by operator differences, and is convenient and quick to operate.

[0125] It can meet the usage requirements for patient support system testing in "YY / T1763-2021 Performance Characteristics of Medical Electrical Equipment and Medical Light Ion Beam Equipment".

[0126] Example 5: exist Figure 16 , Figure 7 , Figure 17 In the illustrated embodiment, a laser positioning system verification method includes verifying the consistency between the center point of the laser positioning system and the center point of the cubic model, verifying the laser line width, and auxiliary verification.

[0127] The verification of the consistency between the center point of the laser positioning system and the center point of the cubic phantom includes the following steps: Step 1: The robotic arm moves the treatment bed to the preset position of the laser lamp, and installs the five laser tracker target balls into the positioning holes of the target ball base. , , , , Place.

[0128] The cubic mold and its base plate are installed using positioning surfaces in the X, Z, and Y directions. After installation, the axes of the target ball base positioning holes on the YZ plane, XY plane, and XZ plane at the center of the cubic mold and the support plate are on the same plane, with deviation values ​​far below the accuracy requirements of the laser positioning line.

[0129] The robotic arm moves the treatment bed board to the positioning center 501 of the laser positioning system, and installs the laser tracker target ball base and the laser tracker target ball into the positioning holes of the target ball base, respectively. , , , , The treatment bed board was finely adjusted to make... , , The target ball of the laser tracker coincides with the theoretical Y-axis value of the positioning center point of the laser positioning system, making... , , The target ball of the laser tracker coincides with the theoretical X-axis value of the positioning center point of the laser positioning system. , The target ball of the laser tracker coincides with the theoretical Z-axis value of the positioning center point of the laser positioning system, such as... Figure 7 As shown.

[0130] Step 2: Make the XOZ planar laser beam pass through the center point 501 of the laser positioning system. Ensure the XOZ planar laser beam aligns with the cubic phantom. , , The XOZ plane scale lines at the point should coincide. If they do not coincide, adjust the internal adjustment device of the laser lamp to make the laser line coincide with the XOZ plane scale line of the cubic mold. This proves that the XOZ plane laser beam passes through the center point of the laser positioning system.

[0131] Step 3: Verify that the YOZ plane laser beam passes through the center point of the laser positioning system: Ensure that the YOZ planar laser beam passes through the cubic phantom. , , The YOZ plane scale lines at the point should coincide. If they do not coincide, adjust the internal adjustment device of the laser lamp to make the laser line coincide with the YOZ plane scale line of the cubic mold. This proves that the YOZ plane laser beam passes through the center point of the laser positioning system.

[0132] Step 4: Make the XOY plane laser beam pass through the center point of the laser positioning system: Ensure the XOY planar laser beam aligns with the cubic phantom. , The XOY plane scale lines of the point should coincide. If they do not coincide, adjust the internal adjustment device of the laser lamp to make the laser line coincide with the XOY plane scale line of the cubic model. This proves that the XOY plane laser beam passes through the center point of the laser positioning system.

[0133] The center point 501 of the laser positioning system is confirmed to be consistent with the center point of the cubic phantom, further demonstrating that the center point of the laser positioning system is consistent with the design value. This laser positioning system verification method meets the usage requirements for testing laser positioning line width and laser positioning accuracy in YY / T 1537-2017 "Performance and Test Methods for Laser Positioning Systems for Radiotherapy".

[0134] Verification of the line width of a laser positioning system includes the following steps: Step 1: Position the XOZ surface laser beam between the short graduation lines on either side of the long graduation line: Check if the XOZ laser beam falls completely between the short graduation lines on both sides of the long graduation line on the cube mold. The laser line width should not exceed the distance between two adjacent short graduation lines. If not, adjust the laser lamp focusing knob.

[0135] Step 2: Ensure the YOZ laser beam falls completely between the short graduation lines on both sides of the long graduation line: Check whether the YOZ laser beam falls completely between the short graduation lines on both sides of the long graduation line on the cubic mold. The laser line width should not exceed the distance between two adjacent short graduation lines. If it does not meet the requirement, adjust the laser lamp focusing knob.

[0136] Step 3: Ensure the XOY laser beam falls completely between the short graduation lines on both sides of the long graduation line: Check whether the XOY laser beam falls completely between the short graduation lines on both sides of the long graduation line on the cubic mold. The laser line width should not exceed the distance between two adjacent short graduation lines. If it does not meet the requirement, adjust the laser lamp focusing knob.

[0137] The steps for auxiliary verification are as follows: Figure 17 As shown, during calibration, users verify that each laser line 20 falls in the middle of the short scale line on the cubic mold to confirm the laser positioning line width and laser positioning accuracy. Simultaneously, the support plate has two orthogonal scale lines, one horizontal and one vertical. The width of these orthogonal scale lines matches the spacing of the short scale lines on the cubic mold. During laser line width calibration, these orthogonal scale lines are used to verify the laser line width and straightness. The XZ plane laser line falls completely within the horizontal scale line of the support plate, and the YZ plane laser line falls completely within the vertical scale line of the support plate.

[0138] Example 6: exist Figure 7 , 18 In the embodiment shown in -23, a method for verifying an image-guided radiotherapy system includes the following steps: Step 1: The center point (3) of the cubic phantom is positioned with the target ball of the laser tracker to the center point 601 of the image-guided radiotherapy system. The robotic arm moves the treatment bed to the preset center point of the image-guided radiotherapy system, fine-tuning the position of the treatment bed so that the laser tracker target ball... , , The Y-value of the coordinate system is consistent with the Y-value of the center point of the image-guided radiotherapy system; the position of the treatment bed is finely adjusted so that the laser tracker target ball... , , The X-coordinate value is consistent with the X-value of the center point of the image-guided radiotherapy system; the position of the treatment bed is finely adjusted so that the laser tracker target ball... , The Z-value of the coordinates is consistent with the Z-value of the center point of the image-guided radiotherapy system. Through the above steps, the tungsten sphere at the center of the cubic phantom is positioned to the center point of the image-guided radiotherapy system. For example... Figure 7As shown, at this time, the center point of the cubic phantom coincides with the center point 601 of the image-guided radiotherapy system.

[0139] Step 2: Test and verify that the tungsten ball (3) is aligned with the center point of the actual image-guided radiotherapy system: Using the exposure function of the image-guided radiotherapy system, view two X-ray images of the cubic phantom in the image preview software. Check whether the image of tungsten metal sphere (3) in the two images is located in the image ( Figure 21 The tungsten ball (3) should be centered vertically and horizontally. If it is centered, it means that the center point of the tungsten ball (3) is consistent with the center point of the actual image-guided radiotherapy system. If they are not consistent, the positions of the detector plate and the tube need to be adjusted.

[0140] Step 3: Test and verify that the imaging geometry between the -X direction flat panel detector and the X-ray tube meets the design values: Check whether the images of tungsten metal spheres (1) and (5) in the -X direction flat plate image overlap. If they overlap, it means that the imaging geometry between the -X direction flat plate detector and the X-ray tube meets the design value. Figure 23 If they do not overlap, the position of the flat panel detector needs to be adjusted until the images of the tungsten metal spheres (1) and (5) overlap.

[0141] Step 4: Test and verify that the imaging geometry between the +X direction flat panel detector and the X-ray tube meets the design values: Check whether the images of tungsten metal spheres (2) and (4) in the +X direction plate image overlap. If they overlap, it means that the imaging geometry between the +X direction plate detector and the X-ray tube meets the design value. Figure 23 If they do not overlap, the position of the flat panel detector needs to be adjusted until the images of the tungsten metal spheres (2) and (4) overlap.

[0142] Step 5: Confirm the target guidance range in the +X direction of the image-guided radiotherapy system: After confirming that the actual position of the center point of the image-guided radiotherapy system matches the design value (the theoretical position of the center point of the image-guided radiotherapy system determined during the overall design of the treatment room), the treatment bed board is moved along the +X direction using a jog mode on a moving bed. The exposure function of the image-guided radiotherapy system is used to view two X-ray images of the cubic phantom in the image preview software. Image registration is performed using the image registration function; after registration, the cubic phantom returns to the center of the image-guided radiotherapy system. The movement distance of the treatment bed board along the +X direction is increased in 1mm increments, and image registration is performed again until the image registration function can no longer obtain accurate registration results. This confirms the target guidance range of the image-guided radiotherapy system in the +X direction.

[0143] Step 6: Same as step 5, confirm the target guidance range in the -X, +Y, -Y, +Z, and -Z directions in sequence.

[0144] Step 7: Verified the accuracy of the positioning correction calculation: Similar to step 5, after the treatment bed board is moved, the distance of movement is recorded. Image registration software is used to calculate the positioning correction, and the deviation between the actual bed movement distance and the calculated positioning correction data is compared. This deviation should be within the acceptable deviation range of the system design. This verifies the accuracy of the positioning correction calculation.

[0145] Step 8: Verified the repeatability of the setup calibration: Repeat step 7 10 times and compare the deviation values ​​of the 10 calculation results. The data repeatability should be within the acceptable range of the system design. This verifies the repeatability of the setup calibration.

[0146] like Figures 18-20 As shown, the materials used for the cubic phantom and the phantom base plate are easily penetrated by X-rays 30, while the built-in tungsten metal spheres are materials that are difficult for X-rays to penetrate. After exposure, the image-guided radiotherapy system leaves a photographic image on the detector plate. Figure 19 , Figure 20 This diagram shows the positions of the tungsten metal spheres embedded inside a cubic phantom and the X-ray transmission. In the diagram, (1), (2), (3), (4), and (5) represent the tungsten metal spheres, respectively. Figure 21 The image shows the results of the flat panel imaging with the negative X-ray detector. Tungsten sphere (3) is located at the center of the X-ray image, and the images of tungsten spheres (1) and (5) overlap. If the images do not overlap, the position of the flat panel detector needs to be adjusted until the images of tungsten spheres (1) and (5) overlap. The same procedure applies to verifying the position of the positive X-ray detector.

[0147] The cubic phantom contains embedded metal markers that are consistent with the requirements in "YY 1650-2019 Performance and Test Methods for X-ray Image-Guided Radiotherapy Equipment". This meets the various test requirements for gold registration mode in "YY 1650-2019 Performance and Test Methods for X-ray Image-Guided Radiotherapy Equipment", including target guidance range, accuracy of positioning correction calculation, and repeatability of positioning calibration.

[0148] Example 7: See Figure 17 , Figure 20 A method for verifying the positioning accuracy of non-isocentric treatment patients is provided, which uses the multifunctional radiotherapy verification device described in Example 1 to perform position calibration on the multifunctional radiotherapy positioning system to further ensure accurate patient positioning in the clinical positioning process. The multifunctional radiotherapy positioning system includes a patient support system 400, a laser positioning system 500, and an image-guided radiotherapy system 600. The center point 501 of the laser positioning system, the center point 601 of the image-guided radiotherapy system, and the treatment center point 700 of the beam port do not overlap. The multifunctional radiotherapy calibration device is installed on the treatment bed of the patient support system 400.

[0149] For boron neutron capture therapy (BNT) treatment rooms, the radiotherapy particles used are hyperthermic neutrons. Microcircuits are highly susceptible to dark current generation in hyperthermic neutron environments, affecting the operational stability of equipment using microcircuit modules. Therefore, the image-guided radiotherapy system commonly used in boron neutron capture therapy rooms is installed far from the beam exit, resulting in a non-isocentric treatment room, unlike other isocentric particle radiotherapy treatment rooms. The center point of the laser positioning system, the center point of the image-guided radiotherapy system, and the treatment center point of the beam exit are not at the same point in the treatment room space (see [reference]). Figure 24 ).

[0150] For non-isocentric treatment rooms, the clinical workflow for boron neutron capture therapy is as follows: 1. The technician uses a radiotherapy positioning membrane to fix the patient to the treatment bed board 10 in the upper position; 2. The treatment bed supports the patient's movement to the center 501 of the laser positioning system (the first laser lamp position). The technician uses the bed transfer handle to fine-tune the position and posture of the treatment bed to ensure that the marking line on the patient's positioning film is aligned with the laser lines on the three planes of the laser positioning system. 3. The treatment bed supports the patient's movement to the center point 601 of the image-guided radiotherapy system. The image-guided radiotherapy system generates a DR image of the patient's current position and compares it with the image taken on the positioning CT to calculate the accurate patient positioning deviation. This deviation is sent to the patient support system, which finely adjusts the patient's spatial position to ensure that the treatment target in the human body is centered in the image-guided radiotherapy system. 4. The treatment bed supports the patient's movement to the treatment center point 700 of the beam port, and the patient is rotated at the corresponding angle according to the irradiation angle in the treatment plan. A laser lamp (secondary laser lamp position) is also installed at the treatment center point 700 of the beam port.

[0151] Based on the above clinical positioning workflow, the boron neutron capture therapy treatment room needs to periodically verify the spatial positions of the three center points of the treatment room, and verify the patient positioning accuracy during the patient positioning process. This workflow is the treatment system positioning accuracy QA (quality assurance) workflow.

[0152] The verification method for the center point of the laser positioning system in the treatment room is as described in Example 5; the verification method for the center point of the image-guided radiotherapy system is as described in Example 6. The treatment center point 700 of the beam port needs to be obtained by using a laser tracker to perform a circle fitting on the end face of the treatment head to obtain the center coordinates, and then extend these coordinates outward by 400mm.

[0153] A method for verifying the accuracy of patient positioning in a non-isocentric treatment room, which utilizes the multifunctional radiotherapy verification device described in Example 1 to verify the accuracy of patient positioning in a non-isocentric treatment room; the verification method includes the following steps: S1: Pre-calibrate the patient treatment system, laser positioning system, and image-guided radiotherapy system in the non-isocentric treatment room; S2: The robotic arm moves the treatment bed board to the center point of the laser positioning system, so that the scale lines on the cube phantom are aligned with the corresponding laser lines of the laser positioning system. The marked points on the cube phantom coincide with the center point of the laser positioning system, thereby obtaining the first positioning deviation of the cube phantom relative to the laser positioning system. S3: The robotic arm moves the treatment bed to the center point of the image-guided radiotherapy system; the image-guided radiotherapy system is used to photograph the phantom, confirming that the phantom's marker point is located in the center of the obtained image, and the image registration software is used to perform registration calculations on the obtained image to obtain the second positional deviation of the phantom relative to the image-guided radiotherapy system. S4: The robotic arm moves the treatment bed board to the center point of the treatment beam; the position of the marked point on the cubic phantom is corrected according to the first and second positioning deviations; S5: Using a laser tracker, calculate the coordinates of the current cubic phantom marker point. If the coordinates are consistent with the coordinates of the beam center point in the treatment position, then the radiotherapy positioning system in the non-isocentric treatment room is accurate.

[0154] The above procedure can serve as a routine QA procedure for patient positioning accuracy when various systems in the treatment room are used in combination.

[0155] The multifunctional radiotherapy calibration device, positioning system, and calibration method described in the above embodiments, when used in conjunction with a laser tracker, can quickly verify the positional deviation of the treatment bed surface, the range of bed surface movement, the rotational range of the patient support device's center, and the accuracy of the lateral movement and rotation of the patient support device; it can also verify the linewidth of the laser positioning system, the perpendicularity of the orthogonal laser lines, and the position of the laser positioning system's center point; and it can rapidly verify the image guidance range of the image-guided radiotherapy system, the accuracy of the positioning correction calculation, the geometric positional relationship, the center point position, and whether the axes of the two sets of X-ray beams are coplanar. The use of this multifunctional radiotherapy calibration device reduces the complex device adjustment process and minimizes system errors caused by differences in user operation.

Claims

1. A multifunctional radiotherapy calibration device, characterized in that: The device includes a laser tracker target ball assembly, a calibration device body (100) with orthogonal scribe lines (12) on a support plate, and a cubic mold (3) with orthogonal scribe lines (32) on a mold body. Several target ball positioning holes are provided on the calibration device body (100) and the cubic mold (3), wherein the target ball positioning holes on the cubic mold are respectively located at the center of each face of the cubic mold. The calibration device body (100) is provided with a surface positioning structure (200) for XYZ three-direction surface mating and positioning with the cubic mold (3). The target ball center positioning hole (24) is provided at the orthogonal point of the orthogonal scribe lines (12) on the support plate.

2. The multifunctional radiotherapy calibration device according to claim 1, characterized in that: The cubic mold (3) has orthogonal engravings (32) perpendicular to each other on its five surfaces: front, back, left, right, and top. Laser line width marking scales (35) are provided at both ends of each orthogonal engraving (32). The width of the laser line width marking scales (35) is greater than the width of the orthogonal engravings (32) and is consistent with the width of the orthogonal engravings (12) on the support plate of the calibration device body.

3. The multifunctional radiotherapy calibration device according to claim 2, characterized in that: The cubic mold (3) has multiple tungsten metal balls (36) inside; the bottom of the cubic mold (3) is provided with a positioning surface mounting structure, which includes a positioning ring.

4. The multifunctional radiotherapy calibration device according to any one of claims 1 to 3, characterized in that: It also includes a pull claw mechanism (6) for adjusting the connection between the calibration device body and the treatment bed board, the pull claw mechanism (6) including a pull claw assembly (7).

5. A multifunctional radiotherapy positioning system, characterized in that: The multifunctional radiotherapy calibration device, including any one of claims 1 to 4, further includes a patient support system (400), a laser positioning system (500), and an image-guided radiotherapy system (600), wherein the multifunctional radiotherapy calibration device is mounted on the treatment bed of the patient support system (400).

6. A multifunctional radiotherapy positioning and verification method, characterized in that: The multifunctional radiotherapy calibration device according to any one of claims 1 to 4 specifically includes the following steps: S1: Connect the calibration device body to the treatment bed board; S2: Select to set the number and position of the laser tracker target ball components separately according to the verification content, or select the number and position of the cubic phantom and the laser tracker target ball components; S3: Verify the patient support system, and / or laser positioning system, and / or image-guided radiotherapy system.

7. The multifunctional radiotherapy positioning and verification method according to claim 6, characterized in that: S21: Select at least three non-collinear support plate target ball base positioning holes, including the target ball center positioning hole, on the calibration device body, and install the laser tracker target ball assembly to calibrate the patient support system.

8. The multifunctional radiotherapy positioning and verification method according to claim 7, characterized in that: S22: Install the cubic phantom on the surface positioning structure (200) of the calibration device body (100), install the laser tracker target ball assembly on the target ball positioning holes on the YZ plane, XY plane and XZ plane of the cubic phantom respectively, and make them consistent with the theoretical coordinate values ​​of the X, Z and Y axes of the positioning center point of the laser positioning system and the center point of the image-guided radiotherapy system respectively, and calibrate the laser positioning system and the image-guided radiotherapy system.

9. The multifunctional radiotherapy positioning and verification method according to claim 6, characterized in that: The method for verifying the patient support system includes the following steps: S311: Multi-point tracking measurement: Select at least 3 non-collinear support plate target ball base positioning holes on the calibration device body, including the target ball center positioning hole, and install the laser tracker target ball respectively; S312: Use a laser tracker to collect multi-point coordinate information of the treatment bed board at any position, and use the multi-point information to calculate the position and orientation of the center point of the treatment area on the treatment bed board at that position. S313: Verify the accuracy performance requirements of bed surface position deviation, bed surface movement range, patient support device center rotation range, and lateral and rotational movement of the patient support device through data calculation results.

10. The multifunctional radiotherapy positioning and verification method according to claim 6, characterized in that: The method for verifying a laser positioning system includes the following steps: S321: Install the cubic phantom on the surface positioning structure of the calibration device body, so that the axes of the target ball positioning holes on the YZ plane, XY plane, and XZ plane passing through the center of the cubic phantom are respectively in the same plane; S322: The robotic arm drives the treatment bed board to move the cubic model to the positioning center of the laser positioning system. Laser tracker target balls are installed in the target ball positioning holes on the YZ plane, XY plane, and XZ plane respectively, and are made to coincide with the theoretical values ​​of the X, Z, and Y axes of the positioning center point of the laser positioning system respectively. S323: Verify that each laser line falls in the middle of the laser line width marking scale line to confirm the laser positioning line width and laser positioning accuracy; when verifying the laser line width, use the support plate on the verification device body to orthogonally mark the laser line width and straightness to recheck the laser line width and straightness. The XZ plane laser line falls completely within the horizontal scale line, and the YZ plane laser line falls completely within the vertical scale line. S324: Align the laser line with the XOZ, YOZ, and XOY plane scale lines of the cubic phantom to confirm that the XOZ, YOZ, and XOY plane laser beams pass through the center point of the laser positioning system respectively.

11. The multifunctional radiotherapy positioning and verification method according to claim 6, characterized in that: The method for verifying an image-guided radiotherapy system includes the following steps: S331: Install the cubic phantom on the surface positioning structure of the calibration device body, so that the axes of the target ball positioning holes on the YZ plane, XY plane, and XZ plane at the center of the cubic phantom are respectively in the same plane; S332: The robotic arm drives the treatment bed to move the cubic phantom to the positioning center of the image-guided radiotherapy system. Laser tracker target balls are installed in the target ball positioning holes on the YZ plane, XY plane, and XZ plane, respectively, and the X, Z, and Y coordinate values ​​of the target balls are made consistent with the X, Z, and Y values ​​of the center point of the laser-guided radiotherapy system. The target ball at the center of the cubic phantom is positioned to the center point of the image-guided radiotherapy system. S333: Use the exposure function of the image-guided radiotherapy system to check whether the photographic image left by the tungsten metal ball on the detector plate coincides with the X-ray imaging center; if the images do not coincide, adjust the position of the plate detector until the images coincide.

12. A method for verifying the accuracy of patient placement in a non-isocentric treatment room, characterized in that: The device utilizes the multifunctional radiotherapy calibration apparatus described in any one of claims 1 to 4 to calibrate the positioning accuracy in non-isocentric treatment rooms; the calibration method includes the following steps: S1: Pre-calibrate the patient treatment system, laser positioning system, and image-guided radiotherapy system in the non-isocentric treatment room; S2: The robotic arm moves the treatment bed board to the center point of the laser positioning system, so that the scale lines on the cube phantom are aligned with the corresponding laser lines of the laser positioning system. The marked points on the cube phantom coincide with the center point of the laser positioning system, thereby obtaining the first positioning deviation of the cube phantom relative to the laser positioning system. S3: The robotic arm moves the treatment bed to the center point of the image-guided radiotherapy system; the image-guided radiotherapy system is used to photograph the phantom, confirming that the phantom's marker point is located in the center of the obtained image, and the image registration software is used to perform registration calculations on the obtained image to obtain the second positional deviation of the phantom relative to the image-guided radiotherapy system. S4: The robotic arm moves the treatment bed board to the center point of the treatment beam; the position of the marked point on the cubic phantom is corrected according to the first and second positioning deviations; S5: Calculate the coordinates of the current cubic phantom marker point. If the coordinates are consistent with the coordinates of the beam center point of the treatment position, then the radiotherapy positioning system of the non-isocentric treatment room is accurate.

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