A calibration device for radiotherapy positioning

Abstract

This utility model discloses a calibration device for radiotherapy positioning, comprising a calibration device body with a plurality of support plate target ball base positioning holes for mounting the target ball of a laser tracker. The calibration device body also has a surface positioning structure for mounting a cubic phantom; wherein a target ball center positioning hole is located at the center of the surface positioning structure. This calibration device, when used in conjunction with a laser tracker, can quickly verify the coincidence of the center point of the treatment bed plate with the treatment center point of the beam port; verify the linewidth, perpendicularity of orthogonal laser lines, and center point position of the laser positioning system; and quickly verify the geometric positional relationship, center point position, and whether the axes of the two X-ray beams are coplanar in the image-guided radiotherapy system. This reduces the cumbersome adjustment process and minimizes system errors caused by differences in user operation.

Description

Technical Field

[0001] This utility model relates to the field of radiotherapy positioning technology, and simultaneously meets the needs of laser positioning system position adjustment, image-guided radiotherapy system position adjustment and patient support system position adjustment. In particular, it relates to a calibration device and method for radiotherapy positioning. Background Technology

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

[0003] The spatial positioning accuracy of the six-degree-of-freedom 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.

[0004] To establish and accurately adjust the positional relationship of the center point, Chinese patent CN117398625A proposes a calibration device and its positioning method for a laser lamp positioning system. This method establishes the positional relationship between the laser positioning line and the beam's center point using a laser tracker and a cubic phantom. Furthermore, a six-dimensional adjustment device on the apparatus adjusts the spatial position of the cubic phantom to achieve isocentric alignment between the laser lamp center and the beam.

[0005] However, the above technical solution has the following drawbacks: First, the adjustment device is set on the bed, which makes the debugging process complicated and the adjustment accuracy may be affected by the operator's operation error. Second, the connection between the three-dimensional model and the device is complex and requires repeated operation, which affects the accuracy. Utility Model Content

[0006] 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 calibration device and method for radiotherapy positioning, which 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.

[0007] The technical solution adopted by this utility model to achieve its invention objective is as follows: a calibration device for radiotherapy positioning, comprising a calibration device body, on which are provided a plurality of positioning holes for the support plate target ball of a laser tracker for mounting, and a surface positioning structure for mounting a cubic phantom; wherein, a target ball center positioning hole is provided at the center of the surface positioning structure. This calibration device for radiotherapy positioning, by providing a plurality of positioning holes on the calibration device body, allows for the rapid insertion and positioning of the laser tracker target ball in the positioning holes according to testing needs, ensuring the repeatability and accuracy of the laser tracker target ball base installation. The surface positioning structure ensures the repeatability and accuracy of the cubic phantom assembly. 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 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 sets of X-ray beams are coplanar in the image-guided radiotherapy system. The use of this multifunctional radiotherapy calibration device reduces the cumbersome device adjustment process and minimizes systematic errors caused by differences in user operation. Preferably, the calibration device body is provided with orthogonal engravings on the base plate, and the surface positioning structure is located at the orthogonal center of the orthogonal engravings on the base plate.

[0008] Preferably, the orthogonal markings on the base plate include horizontal markings and vertical markings on the support plate, and the widths of the horizontal markings and vertical markings on the support plate are the same.

[0009] Preferably, some of the positioning holes are located on the horizontal scale line and the vertical scale line of the support plate.

[0010] Preferably, the calibration device body includes a support plate and an X-ray permeable phantom base plate embedded in the support plate. The phantom base plate needs to have good X-ray permeability; therefore, the calibration device body is divided into a support plate and a phantom base plate made of different materials. The phantom base plate is made of organic polymer material, while the support plate can be made of high-precision metal plate, which provides both rigid support and ensures the repeatability accuracy of the laser tracker target ball base.

[0011] Preferably, the surface positioning structure is disposed on the mold base plate, and the mold base plate is provided with a groove-shaped or protruding XYZ three-directional surface positioning structure that mates with the cubic mold. The positioning surface structure can be a groove-shaped three-directional positioning structure or a protruding three-directional positioning structure provided on the mold base plate. By cooperating with the bottom and side surfaces of the cubic mold, the surface positioning of the cubic mold and the mold base plate in the XYZ directions is ensured, which not only ensures the repeatability and accuracy of the cubic mold assembly, but also makes the installation and operation simple and convenient.

[0012] Preferably, the device also includes a laser tracker target ball assembly, which comprises a laser tracker target ball base and a laser tracker target ball mounted on the base. By using the laser tracker target ball base, it can be quickly connected and positioned with the positioning holes on the calibration device body and the cubic mold, without the need for position adjustment. This results in high positioning accuracy, convenient and quick operation, and precise installation and positioning of the laser tracker target ball. It ensures the repeatability of the laser tracker target ball with the support plate and the cubic mold.

[0013] Preferably, the laser tracker target ball base includes a base body with a bottom positioning plane. The base body has a target ball receiving groove inside, and a magnetic suction component for adsorbing the laser tracker target ball is installed inside the target ball receiving groove. A base insertion post is located at the center of the base positioning plane. The bottom positioning plane and the base insertion post, along with their corresponding positioning holes on the support plate and cubic mold, ensure the repeatability of the laser tracker target ball's position relative to the support plate and cubic mold. The target ball receiving groove inside the base body, and the magnetic suction component inside the target ball receiving groove, allow for quick and accurate adsorption and positioning of the laser tracker target ball on the laser tracker target ball base. This ensures that after the laser tracker target ball is installed on the laser tracker target ball base, the center of the laser tracker target ball and the mounting surface of the laser tracker target ball base have coaxiality and a fixed axial dimensional deviation. Adding this deviation to the axial coordinates of the laser tracker target ball gives the spatial coordinate values ​​of the points on the support plate surface.

[0014] Preferably, the phantom also includes a cubic phantom with X-ray permeability. The five faces of the cubic phantom—front, back, left, right, and top—are each provided with mutually perpendicular orthogonal etched lines. The perpendicular intersection point of the orthogonal etched lines on each face is the center point of the plane, and a target ball base positioning hole is provided at the center point. Multiple tungsten metal spheres are disposed inside the cubic phantom. The cubic phantom needs to have good X-ray permeability; therefore, it is generally made of organic polymer materials. The target ball base positioning holes are located at the centers of the five faces of the cubic phantom, and orthogonal etched lines are also provided. Five laser tracker target ball assemblies can be installed inside the target ball base positioning holes. When X-rays pass through the cubic phantom, the tungsten metal spheres leave a clear image on the detector, which can be used to verify and adjust the spatial position of the laser beam.

[0015] Preferably, laser line width markings are provided at both ends of each orthogonal engraving line on the mold body. The width of the laser line width markings is greater than the width of the orthogonal engraving line on the mold body and is consistent with the width of the orthogonal engraving line on the base plate of the debugging device body. The narrower orthogonal engraving line on the mold body is mainly to verify the straightness of the laser line; the wider laser line width markings are intended to verify that each laser line falls in the middle of the laser line width markings during debugging, thereby confirming the laser positioning line width and laser positioning accuracy.

[0016] Preferably, the bottom of the cubic mold body 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. The bottom surface of the cubic mold body is set as a positioning surface with high-precision dimensions, ensuring the accuracy of repeated assembly of the cubic mold body on the mold body base plate.

[0017] Preferably, the device also includes a claw mechanism for adjusting the connection between the calibration device body and the treatment bed board. The claw mechanism comprises a claw assembly and a locking strip assembly. This claw mechanism connects the calibration device body and the treatment bed board, ensuring relative stability between them. Furthermore, the relative position of the calibration device body and the treatment bed board can be adjusted as needed to meet different testing requirements and, consequently, the support needs of different radiotherapy patients.

[0018] Preferably, the pull claw assembly includes a pull claw body and a locking screw handle disposed on the pull claw body.

[0019] Preferably, the locking strip assembly includes a positioning locking strip and a positioning pin disposed on the positioning locking strip; the calibration device body is provided with a locking positioning hole for engaging with the positioning pin. The pull claw assembly and locking strip assembly enable rapid connection and positioning with the treatment bed board while ensuring installation accuracy.

[0020] The beneficial effects of this invention are as follows: When used in conjunction with a laser tracker, this calibration device for radiotherapy positioning can quickly verify the coincidence of the center point of the treatment area on the treatment bed with the center point of the beam inlet; it can also verify the linewidth, perpendicularity of the orthogonal laser lines, and center point position of the laser positioning system; and it can rapidly verify the 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 calibration device for radiotherapy positioning reduces the cumbersome device adjustment process and minimizes system errors caused by differences in user operation. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a calibration device for radiotherapy positioning according to this utility model.

[0022] Figure 2 This is another structural schematic diagram of the calibration device for radiotherapy positioning according to this utility model.

[0023] Figure 3 yes Figure 2 An exploded view of a calibration device used for radiotherapy positioning.

[0024] Figure 4 This is a schematic diagram of the structure of the laser tracker target ball assembly in this utility model.

[0025] Figure 5 This is a schematic diagram of a cubic model in this utility model.

[0026] Figure 6 This is a schematic diagram showing the distribution of positioning holes on the main body of the verification device in this utility model.

[0027] Figure 7 This is a schematic diagram showing the distribution of positioning holes on the cubic mold body of this utility model.

[0028] Figure 8 This is a schematic diagram of the combined structure of the calibration device for radiotherapy positioning according to this utility model.

[0029] Figure 9 This is a structural schematic diagram of the calibration device assembly for radiotherapy positioning of this utility model from another angle.

[0030] Figure 10 This is an exploded structural diagram of the calibration device assembly for radiotherapy positioning according to this utility model.

[0031] Figure 11 This is a top view of the calibration device assembly for radiotherapy positioning according to this utility model.

[0032] Figure 12 yes Figure 11 Sectional view of AA.

[0033] Figure 13 yes Figure 11 BB section view.

[0034] Figure 14 This is a schematic diagram of the connection between the calibration device for radiotherapy positioning and the treatment bed board according to this utility model.

[0035] Figure 15 This is a schematic diagram of an application structure of this utility model.

[0036] Figure 16 , Figure 17 This is a schematic diagram of another application structure of this utility model.

[0037] Figure 18 This is a schematic diagram of the structure of the cubic phantom and the phantom base plate of this utility model under X-ray penetration.

[0038] Figure 19 A schematic diagram of the structure of the cubic phantom (with embedded tungsten metal spheres) and the phantom base plate through which X-rays penetrate.

[0039] Figure 20 This is a schematic diagram of the flat panel imaging result of the X-ray negative detector in this utility model.

[0040] Figure 21 This is a top view of the cubic model in this utility model.

[0041] Figure 22 yes Figure 21 DD section view.

[0042] Figure 23 yes Figure 21 EE section view (rotated).

[0043] Figure 24 yes Figure 21 FF section view (rotated).

[0044] Figure 25 This is a schematic diagram of an application structure of the calibration device for radiotherapy positioning according to this utility model.

[0045] In the figure: 1. Support plate, 11. Positioning hole of target ball base of support plate, 12. Orthogonal engraving line of base plate, 121. Horizontal scale line of support plate, 122. Longitudinal scale line of support plate, 13. Positioning groove of base plate, 14. Support platform of mold base plate, 15. Fastening hole of base 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. Pulling claw mechanism, 7. Pull claw assembly; 71. Pull claw body; 72. Locking screw handle; 73. Nylon strip; 8. Card strip assembly; 81. Positioning card strip; 82. Positioning pin; 83. Nylon stop; 84. Stop positioning hole; 10. Treatment bed board; 101. Treatment bed board positioning protrusion; 100. Verification device body; 200. Surface positioning structure; 20. Laser line; 30. X-ray; 300, laser positioning system positioning center; 400, image-guided radiotherapy system center point; 500, treatment room. Detailed Implementation

[0046] The present invention will now be described in detail with reference to specific embodiments and accompanying drawings.

[0047] Example 1: See Figures 1-3 In the embodiment shown, a calibration device for radiotherapy positioning is used for rapid confirmation of the spatial center point for radiotherapy, and can simultaneously adjust the center points of the laser positioning system, the image-guided radiotherapy system, and the patient support system.

[0048] like Figure 1 As shown, the calibration device for radiotherapy positioning includes a calibration device body 100. The calibration device body is provided with a plurality of positioning holes for mounting the target ball of the laser tracker. The calibration device body 100 is provided with orthogonal engraving lines 12 on the base plate. At the orthogonal center of the orthogonal engraving lines 12 on the base plate, a surface positioning structure 200 for mounting a cubic phantom is provided. The surface positioning structure 200 is provided with a target ball center positioning hole 24 at its center.

[0049] The calibration device body 100 includes a support plate 1 for movable and adjustable connection with the treatment bed board 10, and a mold base plate 2 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.

[0050] The calibration device for radiotherapy positioning also includes a cubic phantom 3 and a laser tracker target ball assembly.

[0051] 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.

[0052] like Figure 6 As 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 body. A positioning hole 33 for the target ball base of the mold body is set 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 body 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 debugging, 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 body and is consistent with the width of the orthogonal scale line on the bottom plate of the debugging device body.

[0053] 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. Multiple tungsten metal balls 36 are disposed inside the cubic mold body 3. See also... Figures 21-24 In this embodiment, five tungsten metal spheres 36 are embedded inside the cubic phantom. When X-rays pass through the cubic phantom, the tungsten metal spheres can leave a clear image on the detector.

[0054] See Figure 1 Meanwhile, the support plate 1 is provided with two scale lines, one horizontal and one vertical, defined as the orthogonal scale line 12 of the base plate. The orthogonal scale line 12 of the base plate includes the horizontal scale line 121 and the vertical scale line 122 of the support plate. The width of the scale line is consistent with the spacing of the small scale lines on the cubic mold 3. When adjusting the laser line width, the orthogonal scale line 12 of the base plate is used to check the laser line width and straightness. The XZ plane laser line falls completely within the horizontal scale line 121 of the support plate, the YZ plane laser line falls completely within the vertical scale line 122 of the support plate, and the XY plane laser line falls completely within the XY plane small scale line of the cubic mold.

[0055] The support plate 1 is made of high-precision metal plate, 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.

[0056] The support plate 1 is engraved with orthogonal engraving lines 12 along its center point, and the mold base plate is installed in the central area to support the mold.

[0057] In this embodiment, the support plate 1 is a cuboid plate. On one end of the support plate 1, an orthogonal engraving line 12 is engraved along the center point, and a base plate positioning slot 13 is provided. The base 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 base plate positioning slot 13 to support the mold base plate 2. A base 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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.

[0062] 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.

[0063] In this embodiment, a surface positioning structure 200 is provided at the center of the mold base plate 2. The surface positioning structure adopts a groove-shaped positioning surface structure, specifically including a mold insert groove 22 and a mold slot 23. The mold slot 23 is arranged around the bottom of the mold insert groove 22. 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 inserted into 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 can facilitate the direct insertion and installation of the laser tracker target ball base 4 on the mold base plate 2, achieving high-precision positioning.

[0064] 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 arranged laterally. 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.

[0065] A feature 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.

[0066] 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.

[0067] The cubic mold 3 is a detachable and replaceable component, and different specifications of cubic mold 3 can be replaced as needed.

[0068] The cubic phantom 3 is made of organic polymer material and has good X-ray transmittance. The center of the five faces of the cubic phantom 3 (front, back, left, right and top) is provided with phantom target ball base positioning holes 33 for mounting the laser tracker target ball base 4. At the same time, orthogonal engraving lines 32 are engraved on the phantom, which can realize the spatial position verification and adjustment of the laser light beam.

[0069] 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.

[0070] 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 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, Y, and Z directions. After installation, the axes of the target ball base positioning holes on the YZ plane, XY plane, and XZ plane passing through the center of the cubic mold on the cubic mold and the support plate are respectively in the same plane, with deviation values ​​far lower than the accuracy requirements of the laser positioning line position.

[0071] The five phantom target ball base positioning holes 33 are respectively inserted with laser tracker target ball bases 4. The laser tracker target ball is installed on the laser tracker target ball base 4. When X-rays pass through the cubic phantom 3, the tungsten metal ball can leave a clear image on the detector.

[0072] The laser tracker target ball base 5 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.

[0073] like Figure 4As 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 laser tracker target ball 5 is adsorbed inside the target ball receiving groove 42 by the magnet 44. 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. 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.

[0074] 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.

[0075] The pull claw mechanism 6 includes a pull claw assembly 7, which includes a pull claw body 71 and a locking screw handle 72 disposed on the pull claw body 71. A nylon strip 73 is disposed inside the pull claw body 71. The nylon strip 73 is used to cooperate with the bed surface under the treatment bed board for positioning during use and also has a shock absorption function to ensure the stability of the entire device during use. The pull claw body 71 is arranged laterally in a U-shape.

[0076] See Figure 14 In 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.

[0077] 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.

[0078] See Figure 8-13 This calibration device for radiotherapy positioning 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.

[0079] See Figure 14 This is a schematic diagram of the structure of a calibration device used for radiotherapy positioning in conjunction with a treatment bed.

[0080] The patient support system is typically a 6-DOF end-effector bed surface, mainly consisting of a treatment bed board and a robotic arm. It allows for translation and rotation of the bed surface along the X, Y, and Z directions, with its center point being the center of the treatment area on the treatment bed board. The beam center point is typically the geometric center within the range that the particle beam can encompass.

[0081] The treatment bed board 10 is an important component of the patient support system. It is typically made of carbon fiber and has six degrees of freedom: translation along the X, Y, and Z directions and rotation along the X, Y, and Z directions. The treatment bed board 10 achieves these six degrees of freedom through a robotic arm.

[0082] 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 piece from top to bottom with the locking screw handle 72 to achieve the positioning of the relative position of the support plate and the treatment bed board. It is then possible to set a cubic mold or directly set the laser tracker target ball base 4 on the mold base plate 2 as needed.

[0083] 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 the positioning structures on both sides of the treatment bed board, thus enabling multi-position installation of the support plate 1 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 on the treatment bed board via the clips and secured to it by four claw assemblies on both sides, allowing for multi-position installation of the support plate 1. ~ 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.

[0084] 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 the laser tracker target ball on the center positioning hole 24 of the target ball is always in the center position of the treatment bed during repeated disassembly and reassembly of the device.

[0085] 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.

[0086] 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.

[0087] like Figure 15 As shown, in the support plate , , , , Five laser tracker target ball bases 4 and laser tracker target balls 5 are simultaneously installed in the positioning holes 11 of the support plate target ball base. The laser tracker collects five coordinate points of the treatment bed board at any position. Using this five-point information, data calculations can generate the position and orientation of the center point of the treatment area on the treatment bed board at that location. The data calculation results can be used to verify performance requirements such as bed surface position deviation, bed surface movement range, isocentric rotation range of the patient support system, and the accuracy of the lateral movement and rotation of the patient support system.

[0088] 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".

[0089] The cubic mold and its base plate are installed using positioning surfaces in the X, Y, and Z directions. After installation, the axes of the target ball base positioning holes on the YZ, XY, and XZ planes, which pass through the center of the cubic mold, are on the same plane, with deviations far below the accuracy requirements of the laser positioning lines.

[0090] like Figure 25 As shown, within treatment room 500, a robotic arm is used to move the treatment bed board to the positioning center 300 of the laser positioning system. The laser tracker target ball base and target ball are respectively installed in the positioning holes of the target ball base on the support plate and the target ball base. , , , , The treatment bed board was finely adjusted to make... , , The laser tracker target ball is aligned with the theoretical Y-axis value of the positioning center point of the laser positioning system, so that the laser tracker target ball... , , Coinciding with the theoretical X-axis value of the positioning center point of the laser positioning system , The theoretical Z-axis value of the laser tracker target ball coincides with the positioning center point of the laser positioning system (see...). Figure 16 , Figure 7 ).

[0091] The cubic mold has two sets of large, perpendicular scale lines on its front, back, left, right, and top sides. At both ends of each large scale line are small scales marking the width of the laser line. During the processing of the cubic mold, the center point of the positioning hole of the target ball base of the cubic mold is ensured to coincide with the scale line. This coincidence establishes the relationship between the large scale lines and the measurement value of the target ball by the laser tracker.

[0092] like Figure 17 As shown, during debugging, the user checks that each laser line 20 falls in the middle of the small scale line to confirm the width of the laser positioning line and the accuracy of laser positioning. Meanwhile, the support plate has two scale lines, one horizontal and one vertical. The width of the orthogonal scale line 12 on the support plate is consistent with the spacing of the small scale lines on the cubic mold. During laser line width debugging, this scale line is 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.

[0093] It can meet the needs of rapid calibration and debugging of the center point of the orthogonal image-guided radiotherapy system. For example, if the center point of the laser lamp positioning system is consistent at 300, the laser tracker target ball base and the laser tracker target ball are respectively installed in the positioning holes of the target ball base on the support plate and the positioning holes of the target ball base. , , , , The treatment bed board was finely adjusted to make... , , The laser tracker target ball at the location coincides with the theoretical Y-axis value of the center point of the image-guided radiotherapy system, making... , , The target ball of the laser tracker coincides with the theoretical X-axis value of the positioning center point of the image-guided radiotherapy system. , The laser tracker target ball coincides with the theoretical Z-axis value of the positioning center point of the image-guided radiotherapy system, such as... Figure 7 As shown, at this time, the center point of the cubic phantom coincides with the center point 400 of the image-guided radiotherapy system.

[0094] like Figure 18 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 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 20 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.

[0095] 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.

[0096] The calibration device for radiotherapy positioning described in the above embodiments, when used in conjunction with a laser tracker, can quickly verify the coincidence of the center point of the treatment bed and 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 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 cumbersome device adjustment process and minimizes system errors caused by differences in user operation.

Claims

1. A calibration device for radiotherapy positioning, characterized in that: The device includes a calibration device body (100), on which a plurality of support plate target ball base positioning holes (11) for mounting laser tracker target balls are provided, and the calibration device body (100) is provided with a surface positioning structure (200) for mounting a cubic model; wherein, a target ball center positioning hole (24) is provided at the center of the surface positioning structure (200).

2. The calibration device for radiotherapy positioning according to claim 1, characterized in that: The verification device body (100) is provided with orthogonal etched lines (12) on the base plate, and the surface positioning structure (200) is located at the orthogonal center of the orthogonal etched lines (12) on the base plate.

3. The calibration device for radiotherapy positioning according to claim 2, characterized in that: The orthogonal scale lines (12) on the base plate include a horizontal scale line (121) and a vertical scale line (122) on the support plate, and the widths of the horizontal scale line (121) and the vertical scale line (122) on the support plate are the same.

4. The calibration device for radiotherapy positioning according to claim 3, characterized in that: Some of the positioning holes (11) of the target ball base of the support plate are set on the horizontal scale line (121) and the vertical scale line (122) of the support plate.

5. The calibration device for radiotherapy positioning according to any one of claims 1 to 4, characterized in that: The verification device body (100) includes a support plate (1) and an X-ray permeable phantom base plate (2) embedded in the support plate (1).

6. The calibration device for radiotherapy positioning according to claim 5, characterized in that: The surface positioning structure (200) is set on the base plate (2) of the mold body, and the base plate (2) of the mold body is provided with a groove-shaped or protruding XYZ three-direction surface positioning structure that cooperates with the cubic mold body.

7. The calibration device for radiotherapy positioning according to any one of claims 1 to 4, characterized in that: It also includes a laser tracker target ball assembly, which includes a laser tracker target ball base (4) and a laser tracker target ball (5) disposed on the laser tracker target ball base (4).

8. The calibration device for radiotherapy positioning according to claim 7, characterized in that: The laser tracker target ball base (4) includes a base body (41) with a bottom positioning plane. The base body (41) has a target ball receiving groove (42) inside. A magnetic suction component for adsorbing the laser tracker target ball (5) is provided inside the target ball receiving groove (42). A base insertion post (46) is provided at the center of the base positioning plane.

9. The calibration device for radiotherapy positioning according to any one of claims 1 to 4, characterized in that: It also includes a cubic phantom (3) with X-ray permeability. The cubic phantom (3) has five faces, namely front, back, left, right and top, with mutually perpendicular orthogonal etched lines (32). The perpendicular intersection point of the orthogonal etched lines (32) on each face is the center point of the plane. A positioning hole (33) for the phantom target ball base is provided at the center point. Multiple tungsten metal balls (36) are provided inside the cubic phantom (3).

10. The calibration device for radiotherapy positioning according to claim 9, characterized in that: At both ends of each orthogonal grid line (32) of the mold body, there are laser line width marking scale lines (35). The width of the laser line width marking scale lines (35) is greater than the width of the orthogonal grid line (32) of the mold body and is consistent with the width of the orthogonal grid line on the base plate of the calibration device body.

11. The calibration device for radiotherapy positioning according to claim 9, characterized in that: The bottom of the cubic mold (3) is provided with a positioning surface mounting structure, which includes the bottom surface of the cubic mold and a raised or recessed positioning surface on the bottom surface.

12. The calibration device for radiotherapy positioning according to any one of claims 1 to 4, 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).

13. The calibration device for radiotherapy positioning according to claim 12, characterized in that: The pull claw assembly (7) includes a pull claw body (71) and a locking screw handle (72) disposed on the pull claw body (71).

Images