A medical particle accelerator extended beam continuous irradiation beam distribution system

Abstract

The application is a medical particle accelerator extended beam type continuous irradiation beam distribution system, which comprises ionization chamber group A, first scattering body system, second scattering body system, collimator A, ionization chamber group B, energy continuous modulator, wedge-shaped absorber system, collimator B, liftable multi-leaf collimator and ionization chamber arranged in sequence; the design is different from the traditional extended beam type layered irradiation beam distribution system, the energy continuous modulator is used to replace the binary energy modulator and the plate type modulator in the traditional extended beam type distribution system, and the continuous irradiation is realized in cooperation with the multi-leaf collimator; the wedge-shaped absorber system is additionally arranged and cooperates with the multi-leaf collimator to replace the range compensator in the traditional extended beam type distribution system; and the liftable function of the multi-leaf collimator is used to replace the terminal collimator in the traditional extended beam type distribution system.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of medical particle accelerator extended beam continuous irradiation beam distribution system. BACKGROUND

[0002] Traditional medical particle accelerator extended beam beam distribution system generally uses layer-by-layer irradiation method, with a binary energy regulator to adjust the energy of layer-by-layer irradiation, with a rubbing plate modulator to adjust the layer thickness of each layer irradiation, with a multi-leaf collimator to restrict the range of irradiation. This irradiation method is suitable for use in synchrotron with discontinuous beam, but for cyclotron, it has not fully utilized the advantage of continuous beam. SUMMARY

[0003] The present application provides a kind of medical particle accelerator extended beam continuous irradiation beam distribution system to cooperate with the characteristics of cyclotron continuous beam.

[0004] The technical scheme adopted by the present application to achieve its technical purpose is: a kind of medical particle accelerator extended beam continuous irradiation beam distribution system, including ionization chamber group A, first scattering body system, second scattering body system, collimator A, ionization chamber group B, energy continuous modulator, wedge-shaped absorber system, collimator B, liftable multi-leaf collimator and ionization chamber arranged in sequence.

[0005] The axis of the ionization chamber group A and the ionization chamber group B coincides; the geometric center line axis of the ionization chamber coincides;

[0006] The axis of the ionization chamber group A or the ionization chamber group B and the liftable multi-leaf collimator passes through the collimator A and the collimator B, and the rays emitted at the point light source on the axis are parallel to the four inner walls of the collimator A and the collimator B and the liftable multi-leaf collimator, and the projection on the equicentral plane is rectangular;

[0007] The first scattering body system and the second scattering body system are sequentially spaced along the axis of the ionization chamber group A or the ionization chamber group B to form a double scattering system, and when the first scattering body system and the second scattering body system swing left and right, the axis of the first scattering body system and the second scattering body system coincides with the axis of the ionization chamber group A or the ionization chamber group B;

[0008] The energy continuous modulator and the wedge-shaped absorber system are arranged between the ionization chamber group B and the collimator B, and the beam emitted from the ionization chamber group B enters the collimator B after energy adjustment.

[0009] Further, the above-mentioned medical particle accelerator extended beam continuous irradiation beam distribution system further comprises a support frame, the support frame comprises a base composed of two vertically parallel thick plates, a mounting seat A, a mounting seat B and a mounting seat C transversely arranged between the two plates of the base.

[0010] The mounting seat A is arranged on the upper part of the base and is a horizontal mounting plate connected with the two plates of the base at two ends; the ionization chamber group A and the first scattering body system are arranged above the mounting seat A;

[0011] The mounting seat B is arranged in the middle part of the base and is a horizontal mounting plate connected with the two plates of the base at two ends; the second scattering body system is arranged above the mounting seat B, and a space is arranged between the second scattering body system and the bottom surface of the mounting seat A; the collimator A and the ionization chamber B are sequentially arranged below the mounting seat B;

[0012] The mounting seat C is arranged on the bottom part of the base and is a horizontal mounting plate connected with the two plates of the base at two ends; the collimator B, the wedge-shaped absorber system and the energy continuous modulator are sequentially arranged on the mounting seat C, and the energy continuous modulator is arranged below the ionization chamber B; the liftable multi-leaf collimator and the ionization chamber are sequentially arranged below the mounting seat C.

[0013] Further, in the above-mentioned medical particle accelerator extended beam continuous irradiation beam distribution system, the first scattering body system comprises a group of n first scattering bodies in the shape of circular thin plates with different thicknesses, and a moving device for driving the first scattering bodies to move straightly in the front-back direction.

[0014] The n first scattering bodies are arranged horizontally and spaced apart, and the upper surfaces are on a horizontal plane, and the center point of the plane is located at the position of the point light source.

[0015] Under the driving of the moving device, the axis of a certain circular first scattering body is coincided with the beam emitted by the point light source.

[0016] Further, in the above-mentioned medical particle accelerator extended beam continuous irradiation beam distribution system, the second scattering body system comprises n second scattering bodies in the shape of cylinders with the outer edge upper surfaces being convex curved surfaces, and a moving device for driving the second scattering bodies to move in the left-right direction and the front-back direction.

[0017] Further, in the above-mentioned medical particle accelerator extended beam continuous irradiation beam distribution system, the energy continuous modulator comprises a wedge-shaped absorber A with an upward inclined surface and a downward horizontal surface, a wedge-shaped absorber base with a rectangular hole, m wedge-shaped absorbers B with upward inclined surfaces and downward horizontal surfaces, and a moving mechanism for driving the wedge-shaped absorbers B to move in the left-right direction.

[0018] Further, in the above-mentioned medical particle accelerator extended beam continuous irradiation beam distribution system, the moving mechanism comprises a straight moving mechanism and a straight driving mechanism.

[0019] The straight line moving mechanism comprises two straight line guides, two groups of two sliders, a corresponding number of sliding plates and cover plates, the two straight line guides are installed on the upper surface of the mounting seat and are movably connected with the two groups of two sliders respectively, the two groups of two sliders are connected with the sliding plates, and the cover plates are connected with the sliding plates.

[0020] Further, in the medical particle accelerator extended beam continuous irradiation beam distribution system, the wedge-shaped absorber system comprises N groups of two rotatable wedge-shaped absorbers C with inclined upper surfaces and flat lower surfaces and wedge-shaped absorber translation and rotation mechanisms for driving the rotatable wedge-shaped absorbers C to rotate and translate stably.

[0021] Further, in the medical particle accelerator extended beam continuous irradiation beam distribution system, the liftable multi-leaf collimator comprises a multi-leaf collimator and an up-down moving mechanism for driving the multi-leaf collimator to move up and down.

[0022] In the present application, the binary energy modulator and the rubbing plate type modulator in the conventional extended beam distribution system are replaced by the energy continuous modulator, and the continuous irradiation is realized in cooperation with the multi-leaf collimator; the range compensator in the conventional extended beam distribution system is replaced by the wedge-shaped absorber system and the multi-leaf collimator; and the terminal collimator in the conventional extended beam distribution system is replaced by the liftable function of the multi-leaf collimator.

[0023] The present application will be described in detail below in combination with the drawings and specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 , distribution system component configuration diagram;

[0025] Figure 2 , distribution system in the position diagram of rectangular coordinate system;

[0026] Figure 3 , ionization chamber group and collimator position diagram;

[0027] Figure 4 , mounting seat and multi-leaf collimator position diagram;

[0028] Figure 5 , first scatterer system structure diagram;

[0029] Figure 6 , second scatterer system structure diagram;

[0030] Figure 7 , energy continuous modulator structure diagram;

[0031] Figure 7-1 , energy continuous modulator schematic diagram one;

[0032] Figure 7-2, Energy continuous modulator schematic diagram 2

[0033] Figure 7-3 , Energy continuous modulator schematic diagram 3

[0034] Figure 8 , Wedge absorber system structure diagram

[0035] Figure 9 , Wedge absorber system schematic diagram

[0036] Figure 10 , Lifting multi-leaf collimator structure diagram

[0037] Figure 11 , Dispensing system appearance diagram

[0038] Figure 12-1 Continuous irradiation schematic diagram 1

[0039] Figure 12-2 Continuous irradiation schematic diagram 2

[0040] Figure 12-3 Continuous irradiation schematic diagram 3

[0041] Figure 12-4 Continuous irradiation schematic diagram 4

[0042] Figure 12-5 Continuous irradiation schematic diagram 5

[0043] Figure 12-6 Continuous irradiation schematic diagram 6

[0044] Figure 13 , Lifting collimator replaces terminal collimator schematic diagram

[0045] Figure symbol:

[0046] 1, a base composed of two inverted trapezoidal thick plates

[0047] 2, ionization chamber group A

[0048] 3, first scattering body system

[0049] 3-1, n thick and thin different circular thin plate shaped first scattering bodies

[0050] 3-2, an X-axis direction linear motion mechanism XA

[0051] 3-3-1, two linear guide rails XA

[0052] 3-2-2, two groups of two sliders in each group XA

[0053] 3-2-3, a slide plate containing n counterbores and concentric through holes

[0054] 3-2-4, a cover plate with n through holes

[0055] 3-3, an X-axis linear drive mechanism XA

[0056] 4, a mounting base A

[0057] 5, a second scatterer system

[0058] 5-1, n second scatterers in the shape of cylinders with curved convex upper surfaces

[0059] 5-2, a Z-axis linear movement mechanism ZA

[0060] 5-2-1, two linear guides ZA

[0061] 5-2-2, two sets of two sliders ZA

[0062] 5-2-3, a rectangular frame-shaped slide plate A

[0063] 5-3, a Z-axis linear drive mechanism ZA

[0064] 5-4, an X-axis linear movement mechanism XB

[0065] 5-4-1, two linear guides XB

[0066] 5-4-2, two sets of two sliders XB

[0067] 5-4-3, a slide plate with two rows of n / 2 through holes each

[0068] 5-5, an X-axis linear drive mechanism XB

[0069] 6, a mounting base B

[0070] 7, a collimator A

[0071] 8, an ionization chamber group B

[0072] 9, an energy continuous modulator

[0073] 9-1, a wedge-shaped absorber A with an upward-facing slope and a downward-facing plane

[0074] 9-2, a wedge-shaped absorber base with a rectangular hole

[0075] 9-3, m wedge-shaped absorbers B with upward-facing slopes and downward-facing planes

[0076] 9-4, m Z-axis linear movement mechanisms ZB

[0077] 9-4-1, a guide rail mounting base with a rectangular hole and a long side in the Z-axis direction

[0078] 9-4-2, two straight linear guides ZB

[0079] 9-4-3, two groups of two sliders ZB

[0080] 9-4-4, one rectangular frame-shaped slide B

[0081] 9-5, m Z-axis direction linear driving mechanisms ZB

[0082] 10, wedge-shaped absorber system

[0083] 10-1, N groups of two rotatable wedge-shaped absorbers C with inclined upper surface and flat lower surface

[0084] 10-2, N groups of two wedge-shaped absorber translation and rotation mechanisms

[0085] 10-2-1, one U-shaped X-axis direction guide seat

[0086] 10-2-2, one X-axis direction guide XC

[0087] 10-2-3, two sliders XC

[0088] 10-2-4, one L-shaped swivel shaft base

[0089] 10-2-5, one swivel shaft with its axis parallel to the Y-axis and intersecting the X-axis

[0090] 10-2-6, one wedge-shaped absorber mounting seat

[0091] 10-2-7, one X-axis direction linear driving mechanism XC

[0092] 10-2-8, one rotation driving mechanism

[0093] 11, collimator B

[0094] 12, mounting seat C

[0095] 13, liftable multi-leaf collimator

[0096] 13-1, one multi-leaf collimator

[0097] 13-2, one Y-axis direction linear moving mechanism Y

[0098] 13-2-1, four Y-axis direction linear guides Y

[0099] 13-2-2, four groups of two sliders Y

[0100] 13-2-3, two open upward U-shaped slides

[0101] 13-3, one Y-axis direction linkage driving mechanism Y

[0102] 13-3-1, four Y-axis direction linear driving mechanisms Y

[0103] 13-3-2, one belt mechanism

[0104] 13-3-2-1, six belts

[0105] 13-3-2-2, three belts

[0106] 13-3-2-3, two rectangular linear channels

[0107] 14, ionization chamber

[0108] 15-1, one upper reinforcing plate

[0109] 15-2, two lateral inclined reinforcing plates

[0110] 1001, point light source

[0111] 1002, isocenter plane

[0112] 1003, delivery system maximum field

[0113] 1004, isocenter

[0114] 1005, rectangular ray in which the isocenter plane and the delivery system maximum field coincide

[0115] 1006, human body

[0116] 1007, tumor

[0117] 1008, beam

[0118] 1009, line connecting the point light source and the isocenter

[0119] 1010, ray parallel to the leaf side wall and the point light source DETAILED DESCRIPTION

[0120] Example 1, as Figure 1As shown, the embodiment is a medical particle accelerator extended beam continuous irradiation beam distribution system, which comprises ionization chamber group A2, first scatterer system 3, second scatterer system 5, collimator A7, ionization chamber group B8, energy continuous modulator 9, wedge absorber system 10, collimator B11, liftable multi-leaf collimator 13 and ionization chamber 14 arranged in sequence; the axis of ionization chamber group A2 and ionization chamber group B8 (Y axis) coincides; the geometric center line axis of ionization chamber 14 (Y axis) coincides; the axis of ionization chamber group A2 or ionization chamber group B8, liftable multi-leaf collimator 13 (Y axis) passes through collimator A7 and collimator B11, the rays emitted at point light source 1001 on the axis (Y axis) are parallel to the four inner walls of collimator A7 and collimator B11, liftable multi-leaf collimator 13, and the projection on the equal center plane 1002 is a rectangle; the first scatterer system 3 and the second scatterer system 5 are arranged in sequence along the axis of ionization chamber group A2 or ionization chamber group B8 (Y axis) to form a double scattering system, when the first scatterer system 3 and the second scatterer system 5 swing left and right, the axis of the first scatterer system 3 and the second scatterer system 5 coincides with the axis of ionization chamber group A2 or ionization chamber group B8 (Y axis); the energy continuous modulator 9 and the wedge absorber system 10 are arranged between ionization chamber group B8 and collimator B11, and the beam emitted from ionization chamber group B8 enters collimator B11 after energy adjustment.

[0121] For the convenience of description, an XYZ coordinate system is set, the vertical direction is Y axis, the direction of the beam coincides with Y axis, the beam is downward, that is, the geometric center line axis of ionization chamber 14 coincides, XZ plane is a horizontal plane perpendicular to Y axis, X direction represents front and back direction, and Z direction represents left and right direction. Figure 3

[0122] As shown, Figure 2 ​As shown, the beam delivery system of this embodiment is installed in a support frame. The support frame includes a base 1 composed of two thick plates arranged vertically parallel on both sides, and mounting seats A4, B6, and C12 arranged horizontally between the two plates of the base 1. Mounting seat A4 is located on the upper part of the base 1 and is a horizontal mounting plate with both ends connected to the two plates of the base 1. The ionization chamber assembly A2 and the first scattering system 3 are installed above mounting seat A4. Mounting seat B6 is located in the middle of the base 1 and is a horizontal mounting plate with both ends connected to the two plates of the base 1. Mounting seat B6 is mounted on... The second scatterer system 5 is installed, with a gap between the second scatterer system 5 and the bottom surface of the mounting base A4; the collimator A7 and the ionization chamber B8 are installed sequentially below the mounting base B6; the mounting base C12 is located at the bottom of the base and is a horizontal mounting plate with its two ends connected to the two plates of the base 1 respectively; the collimator B11, the wedge-shaped absorber system 10 and the energy continuous modulator 9 are installed sequentially on the mounting base C12, with the energy continuous modulator 9 located below the ionization chamber B8; the liftable multi-leaf collimator 13 and the ionization chamber 14 are installed sequentially below the mounting base C12.

[0123] Specifically, such as Figure 1 and Figure 2 As shown, the base 1 is in an XYZ rectangular coordinate system with the Y-axis as the vertical axis. The inner and outer surfaces of its two thick plates are parallel to the XY plane and perpendicular to the Z-axis. The upper and lower surfaces of the two thick plates are parallel to the XZ plane (horizontal plane) and perpendicular to the Y-axis. The two thick plates are wider at the top and narrower at the bottom, separated by a distance, and mirror-symmetrical with respect to the XY plane. The geometric center of the base 1, viewed from the Y-axis direction, coincides with the Y-axis. The ionization chamber assembly A2 is placed between the two uppermost thick plates of the base 1. The first scatterer system 3 is placed below the ionization chamber assembly A2, above the mounting base A4, between the two thick plates of the base 1, and connected to the mounting base A4. The second scatterer system 5 is placed at a certain distance below the mounting base A4, above the mounting base B6, between the two thick plates of the base 1. The base 1 is located between and connected to the mounting base B6; the collimator A7 is located below the mounting base B6 and connected to it; the ionization chamber assembly B8 is located below the collimator A7; the energy continuous modulator 9 is located below the ionization chamber assembly B8 and is connected to the inner surfaces of the two thick plates of the base 1 respectively; the wedge-shaped absorber system 10 is located below the energy continuous modulator 9 and is connected to the inner surfaces of the two thick plates of the base 1 respectively; the collimator B11 is located below the wedge-shaped absorber system 10 and is connected to the upper surface of the mounting base C12 below it; the liftable multi-leaf collimator 13 is located below the mounting base C12 and is connected to the outer surfaces of the two thick plates of the base 1 respectively; the ionization chamber 14 is located below the liftable multi-leaf collimator 13 and is connected to it.

[0124] like Figure 3As shown, the axis of the cylinder of ionization chamber group A2 and ionization chamber group B8 coincides with the Y axis; four inner walls of collimator A7 and collimator B11 are parallel to the rays emitted at point light source 1001 on the Y axis, and are parallel to the X axis and Z axis respectively, their projections on the isocenter plane 1002 coinciding with the XZ plane are rectangular, which is the maximum field of the delivery system 1003, and its geometric center is the isocenter 1004, the straight line between point light source 1001 and isocenter 1004 coincides with the Y axis.

[0125] As shown in Figure 4 , the surfaces of mounting seat A4, mounting seat B6 and mounting seat C12 are perpendicular to the Y axis, and their two end faces in the X axis direction are connected to the inner side faces of the two thick plates of base 1 respectively; a trapezoidal through hole is formed in the surface of each of them, and the four inner side walls of the through hole are parallel to the rays emitted at point light source 1001, and their projections on the isocenter plane 1002 coincide with the maximum field 1003; when the lifting multi-leaf collimator 13 is lowered to the limit position, its maximum field on the isocenter plane 1002 coincides with the maximum field 1003 of the delivery system; the geometric center of the ionization chamber 14 viewed from the Y axis direction coincides with the Y axis. In the figure, mounting seat C12 is cut open so that the multi-leaf collimator below it can be seen.

[0126] As shown in Figure 2 and Figure 5 , the first scatterer system (3) comprises a group of n first scatterers 3-1 in the shape of circular thin plates with different thicknesses, an X axis direction linear moving mechanism XA3-2 and an X axis direction linear driving mechanism XA3-3, the n first scatterers 3-1 are arranged in intervals along the X direction, and their upper surfaces are on a plane perpendicular to the Y axis, and the intersection of the plane with the Y axis is the position of point light source 1001; the X axis direction linear moving mechanism XA3-2 comprises two linear guide rails XA3-2-1, two groups of two sliders XA3-2-2 each, a slide plate 3-2-3 containing n counterbores and concentric through holes, and a cover plate 3-2-4 containing n through holes, the two linear guide rails XA3-2-1 are installed on the upper surface of mounting seat A4 and are movably connected to the two groups of two sliders XA3-2-2 respectively; the two groups of two sliders XA3-2-2 are connected to the slide plate 3-2-3 containing n counterbores; the group of n first scatterers 3-1 are respectively embedded in the n counterbores of the slide plate 3-2-3; the cover plate 3-2-4 containing n through holes is connected to the slide plate 3-2-3 containing n counterbores and presses the edges of the n first scatterers 3-1; the X axis direction linear driving mechanism XA3-3 is connected to the upper surface of mounting seat 4 and is movably connected to the X axis direction linear moving mechanism XA3-2, and under the driving of the X axis direction linear driving mechanism XA3-3, the axis of a certain circular first scatterer 3-1 can coincide with the Y axis. In order to be able to see the first scatterer 3-1, Figure 5The cover plate 3-2-4 is moved by a distance.

[0127] As shown in Figure 2 and Figure 6 The second scattering body system 5 includes n cylindrical second scattering bodies 5-1 with curved convex upper surfaces of the outer edges, a Z-axis linear movement mechanism ZA5-2, a Z-axis linear drive mechanism ZA5-3, an X-axis linear movement mechanism XB5-4, and an X-axis linear drive mechanism XB5-5. The Z-axis linear movement mechanism ZA5-2 includes two linear guides ZA5-2-1, two groups of two sliders ZA5-2-2, and a rectangular frame-shaped slide plate A5-2-3. The X-axis linear movement mechanism XB5-4 includes two linear guides XB5-4-1, two groups of two sliders XB5-4-2, and a slide plate 5-4-3 with two rows of n / 2 holes each. The two linear guides ZA5-2-3 are connected to the upper surface of the mounting base B6 and are respectively movably connected to the two groups of two sliders ZA5-2-2. The two groups of two sliders ZA5-2-2 are connected to the rectangular frame-shaped slide plate A5-2-3. The upper surfaces of the two edges of the rectangular frame-shaped slide plate A5-2-3 are respectively connected to the two linear guides XB5-4-1. The two linear guides XB5-4-1 are respectively movably connected to the two groups of two sliders XB5-4-2. The two groups of two sliders XB5-4-2 are connected to the slide plate 5-4-3 with two rows of n / 2 holes each. The n cylindrical second scattering bodies 5-1 are respectively embedded in the two rows of n / 2 holes of the slide plate 5-4-3. The Z-axis linear drive mechanism ZA5-3 is installed on the upper surface of the mounting base B6 and is movably connected to the Z-axis linear movement mechanism ZA5-2. The X-axis linear drive mechanism XB5-5 is installed on the upper surface of the rectangular frame-shaped slide plate A5-2-3 and is movably connected to the X-axis linear movement mechanism XB5-4. Under the joint drive of the Z-axis linear drive mechanism ZA5-3 and the X-axis linear drive mechanism XB5-5, the cylindrical axis of a certain second scattering body 5-1 can coincide with the Y-axis.

[0128] To clearly see the second scattering body 5-1, a certain second scattering body 5-1 is lifted by a distance.

[0129] The first scattering body system 3 and the second scattering body system 5 form a double scattering system, and the principle is not different from that of a traditional double scattering system, which will not be described again.

[0130] In this embodiment, the up-and-down moving device, the left-and-right moving device, and the front-and-back moving device have the same structure. Basically, a slide rail is arranged in this direction, a slide block is arranged on the slide rail, the slide block is connected with the moving device, and a linear driving device such as a motor is arranged to drive the slide block to slide on the slide rail to realize the movement. In practice, the position of the device can be controlled by controlling the linear driving mechanism through a computer.

[0131] As shown in Figure 2 and Figure 7 , the energy continuous modulator 9 comprises a wedge-shaped absorber A9-1 with an upward slope and a downward plane, a wedge-shaped absorber base 9-2 with a rectangular hole, m wedge-shaped absorbers B9-3 with an upward slope and a downward plane, m Z-axis direction linear moving mechanisms ZB9-4, and m Z-axis direction linear driving mechanisms ZB9-5. Each Z-axis direction linear moving mechanism ZB9-4 comprises a guide rail mounting base 9-4-1 with a rectangular hole with a long side in the Z direction, two linear guides ZB9-4-2, two groups of two slide blocks ZB9-4-3, and a rectangular frame-shaped slide plate B9-4-4. The wedge-shaped absorber A9-1 is arranged above the rectangular hole of the wedge-shaped absorber base 9-2. The two end faces of the wedge-shaped absorber base 9-2 in the X-axis direction are respectively connected with the inner side faces of the two thick plates of the base 1. The two end faces of the guide rail mounting base 9-4-1 in the X-axis direction are respectively connected with the inner side faces of the two thick plates of the base 1. The linear guides ZB9-4-2 are connected with the bottom surface of the guide rail mounting base 9-4-1 and are respectively movably connected with the two groups of two slide blocks ZB9-4-3. The two groups of two slide blocks ZB9-4-3 are connected with the rectangular frame-shaped slide plate B9-4-4. The upper surface of the rectangular frame-shaped slide plate B9-4-4 is connected with a wedge-shaped absorber B9-3. The m Z-axis direction linear driving mechanisms ZB9-5 are respectively connected with the two thick plates of the base 1 and are respectively movably connected with the corresponding m Z-axis direction linear moving mechanisms ZB9-4. The m Z-axis direction linear moving mechanisms ZB9-4 are arranged in the Y-axis direction from top to bottom. The m Z-axis direction linear driving mechanisms ZB9-5 are alternately arranged from left to right in the Z-axis direction. The wedge-shaped absorber A9-1 is arranged below the m Z-axis direction linear moving mechanisms ZB9-4 together with the wedge-shaped absorber base 9-2. The projections of the m rectangular holes of the m guide rail mounting bases 9-4-1 and the rectangular hole of the wedge-shaped absorber base 9-2 on the isocenter plane 1002 coincide with the maximum field of the distribution system 1003. Under the driving of the m Z-axis direction linear driving mechanisms ZB9-5, the m wedge-shaped absorbers B9-3 can respectively move in the Z-axis direction.

[0132] For a clear understanding of the detailed structure, the uppermost Z-axis direction linear moving mechanism ZB9-4 in Figure 7 is split into two parts.

[0133] The working principle of the energy continuous modulator 9 is explained as follows. The thickness of the beam passing through the absorber is proportional to the absorbed energy.

[0134] Figure 7-1 The wedge-shaped absorber A9-1 and the wedge-shaped absorber B9-3 are shown separately, and the initial positions thereof are shown in the figure.

[0135] As shown in Figure 7-2 , the m wedge-shaped absorbers A9-1 can be sequentially advanced, and the final positions thereof are shown in the figure, which correspond to the maximum energy modulation amplitude.

[0136] As shown in Figure 7-3 , in order to show the energy modulation amplitude between zero and the maximum energy modulation amplitude, the positions of the wedge-shaped absorber A9-1 and the wedge-shaped absorber B9-3 are rearranged.

[0137] The steps are as follows:

[0138] 1. The slopes of the m wedge-shaped absorbers B9-3 are connected end to end and coincide with a virtual slope;

[0139] 2. The m wedge-shaped absorbers B9-3 connected end to end are placed on a stepped base;

[0140] 3. The wedge-shaped absorber A9-1 is buckled on the slope formed by the m wedge-shaped absorbers B9-3 connected end to end after being reversed in direction.

[0141] The above steps 1 and 2 are equivalent to constructing a long wedge-shaped plate, so that the advancement of the m wedge-shaped absorbers B9-3 is equivalent to the sliding of the reversed wedge-shaped absorber A9-1 on the slope of the long wedge-shaped plate to different positions, and the longitudinal combined thickness thereof with the wedge-shaped absorber B9-3 and the stepped base is the thickness required for a certain energy modulation amplitude. In the figure, the upper surface of the wedge-shaped absorber A9-1 is parallel to the bottom surface of the stepped base, which indicates that the adjusted energy distribution is uniform. In theory, a long wedge-shaped absorber can be used instead of the m wedge-shaped absorbers B9-3, but it is too long and too much absorber material is used.

[0142] As shown in Figure 8As shown, in this embodiment, both rotation and movement of the wedge-shaped absorber C10-1 are to be implemented.The wedge absorber system 10 comprises N sets of two rotatable wedge absorbers C10-1 with inclined upper surface and flat lower surface and N sets of two wedge absorber translation and rotation mechanisms 10-2. Each wedge absorber translation and rotation mechanism 10-2 comprises a U-shaped X-axis direction guide rail seat 10-2-1, an X-axis direction linear guide rail XC10-2-2, two sliders XC10-2-3, an L-shaped rotation shaft base 10-2-4, a rotation shaft 10-2-5 with its axis parallel to Y-axis and intersecting with X-axis, a wedge absorber mounting seat 10-2-6, an X-axis direction linear driving mechanism XC10-2-7 and a rotation driving mechanism 10-2-8. The U-shaped opening of the U-shaped X-axis direction guide rail seat 10-2-1 faces Z-axis direction, and the two end faces of the U-shaped arms thereof are connected with the inner side of one of the two thick plates of the base 1. The X-axis direction linear guide rail XC10-2-2 is connected with the outer side of the U-shaped top of the U-shaped guide rail seat 10-2-1 and movably connected with the two sliders XC10-2-3. The two sliders XC10-2-3 are connected with the outer side of the vertical surface of the L-shaped rotation shaft base 10-2-4. The upper surface of the horizontal surface of the L-shaped rotation shaft base 10-2-4 is connected with the rotation shaft 10-2-5. A through hole with the inner diameter of the rotation shaft 10-2-5 as radius is formed in the horizontal surface of the L-shaped rotation shaft base 10-2-4 along the axis direction of the rotation shaft 10-2-5. The rotation shaft 10-2-5 is connected with the wedge absorber mounting seat 10-2-6. The upper surface of the wedge absorber mounting seat 10-2-6 is connected with the wedge absorber C10-1. A rectangular hole is formed in the surface of the wedge absorber mounting seat 10-2-6 along the axis direction of the rotation shaft 10-2-5, and the projection of the rectangular hole on the isocenter plane 1002 coincides with the maximum field of the distribution system 1003. The X-axis direction linear driving mechanism XC10-2-7 is installed on the U-shaped X-axis direction guide rail seat 10-2-1 and movably connected with the L-shaped rotation shaft base 10-2-4. Under the driving of the X-axis direction linear driving mechanism XC10-2-7 installed on the U-shaped X-axis direction guide rail seat 10-2-1, the L-shaped rotation shaft base 10-2-4 can move along X-axis direction, so that the projection of the rectangular hole on the isocenter plane 1002 coincides with the maximum field of the distribution system 1003. The rotation driving mechanism 10-2-8 is installed on the upper surface of the L-shaped rotation shaft base 10-2-4 and movably connected with the rotation shaft 10-2-5. Under the driving of the rotation driving mechanism 10-2-8, the wedge absorber mounting seat 10-2-6 and the wedge absorber C10-1 can rotate with the axis line of the rotation shaft 10-2-5 as the axis. The N sets of wedge absorbers C8-1 and the N sets of wedge absorber translation and rotation mechanisms 10-2 are arranged in Y-axis direction. In each set of two wedge absorber translation and rotation mechanisms 10-2, one translation and rotation mechanism 10-2 is located at a position rotated by 180° around Y-axis relative to the other translation and rotation mechanism 10-2.

[0143] The working principle of the wedge-shaped absorber system 10 is shown in Figure 9 As shown in Fig. a, the whole distribution system rotates an angle around the Z axis, and due to the different subcutaneous depths of the human body 1006, the end face of the beam 1008 is no longer approximately perpendicular to the line 1009 from the point source to the isocenter, which is not convenient for the implementation of the continuous irradiation method. To change this situation, as shown in Fig. Figure 9 A wedge-shaped plate 10-1 is added in the path of the beam 1008, so that the end face of the beam 1008 in the human body is approximately perpendicular to the line 1009 from the point source to the isocenter.

[0144] Due to the different deflection angles of the distribution system, the subcutaneous depth difference of the edge rays of the beam 1008 is large, and the present application designs m wedge-shaped plates 10-1 with different inclination angles. Considering the complexity of the structure of different parts of the human body, the present application allows each wedge-shaped plate 10-1 to rotate an arbitrary angle with the line 1009 from the point source to the isocenter as the axis.

[0145] As shown in Fig. Figure 10As shown, the elevatable multi-leaf collimator 13 comprises a multi-leaf collimator 13-1, a Y-axis linear motion mechanism Y13-2, a Y-axis linkage driving mechanism Y13-3. The Y-axis linear motion mechanism Y13-2 comprises four Y-axis linear guides Y13-2-1, four groups of two sliders Y13-2-2, two open upward U-shaped slides 13-2-3. Two groups of the four Y-axis linear guides Y13-2-1 are respectively connected to the outer sides of the two thick plates of the base 1, and the two groups are in symmetrical positions on the two sides of the YZ plane. The four groups of two sliders Y13-2-2 are respectively movably connected to the four Y-axis linear guides Y13-2-1. The two open upward U-shaped slides 13-2-3, one of which has two inner sides of the two arms connected to the two groups of two sliders Y13-2-2 on the one side of the YZ plane, and the other has two inner sides of the two arms connected to the two groups of two sliders Y13-2-2 on the other side of the YZ plane. The two sides of the multi-leaf collimator 13-1 are respectively connected to the inner walls below the two U-shaped slides 13-2-3. The Y-axis linkage driving mechanism Y13-3 comprises four Y-axis linear driving mechanisms Y13-3-1 and a belt wheel mechanism 13-3-2. The four Y-axis linear driving mechanisms Y13-3-1 are respectively connected to the outer sides of the two thick plates of the base 1 and movably connected to the four arms of the two U-shaped slides 13-2-3. The belt wheel mechanism 13-3-2 comprises six belt wheels 13-3-2-1, three belts 13-3-2-2 and two rectangular linear channels 13-3-2-3. Among the six belt wheels 13-3-2-1, two groups of four belt wheels are respectively connected to the two Y-axis linear driving mechanisms Y13-3-1 on the outer side of one of the two thick plates of the base 1, and the remaining two are respectively connected to the two Y-axis linear driving mechanisms Y13-3-1 on the outer side of the other thick plate. Among the three belts 13-3-2-2, one belt is movably connected to two belt wheels 13-3-2-1 on the outer side of one of the two thick plates of the base 1, and the remaining two belts 13-3-2-2 pass through the thick plate of the base 1 and are movably connected to the remaining two groups of two belt wheels 13-3-2-1. The two rectangular linear channels 13-3-2-3 are sleeved on the two belts 13-3-2-2 passing through the two thick plates of the base 1 and connected to the inner sides of the two thick plates of the base 1. Driving one of the four Y-axis linear driving mechanisms Y13-3-1 can make the four Y-axis linear driving mechanisms Y13-3-1 linkage through the belt wheel mechanism 13-3-2, drive the multi-leaf collimator 13-1 to move up and down along the Y direction through the two U-shaped slides 13-2-3. The bottom surface of the multi-leaf collimator 13-1 is connected to the ionization chamber 14.

[0146] As Figure 2 and Figure 11As shown, a reinforced base 1 is added with an upper reinforcing plate 15-1 and two lateral inclined reinforcing plates 15-2, wherein the surface of the upper reinforcing plate 15-1 is perpendicular to the Y-axis and connected with the upper surfaces of the two thick plates of the base 1; the surfaces of the two lateral inclined reinforcing plates 15-2 are parallel to the Z-axis and connected with the trapezoidal lateral surfaces of the two thick plates of the base 1.

[0147] The two rectangular straight channels 13-3-2-3 are added without destroying the vacuum state inside the distribution system.

[0148] As shown in Figure 12-1 , 12-2 , 12-3, 12-4, 12-5, 12-6, the working principle of the continuous irradiation of the distribution system of the embodiment is shown.

[0149] As shown in Figure 12-1 , the principle shows that a double-layer multi-leaf collimator is selected, one leaf is extracted from the lower leaf group on the left side, and one leaf is extracted from the upper leaf group on the right side, and it is ensured that the side surfaces of the two leaves are parallel, and the two leaves are called a leaf pair. A plane coinciding with the two side walls of the leaf pair is tangent to the tumor 1007, and a tumor "slice" is cut out. The line from the point light source 1001 to the lowest point of the bottom edge of the tumor slice is the baseline, and the left and right leaves cross the baseline to form complete shielding. At this time, the beam 1008 emitted by the point light source is divided into two parts, the beam above the two leaves is represented by a solid line, representing the actual existing rays; the beam below the two leaves is represented by a dashed line, representing the theoretically calculated virtual rays, and the end surface of the virtual rays in the human body 1006 slightly exceeds the bottom edge of the tumor slice. The end surface of the beam 1008 is the position of the Bragg peak. The continuous irradiation begins.

[0150] Through the progression of the m wedge-shaped absorbers B9-3 in the energy continuous modulator 9, the combined thickness of the wedge-shaped absorber A9-1 and the wedge-shaped absorber B9-3 is increased, so that the end surface of the Bragg peak of the beam 1008 rises, and when it contacts the bottom edge of the tumor 1007 slice, the two leaves in the shielding state retreat, release the light beam, and ensure that the width of the beam 1008 matches the height of the rising beam end surface. As shown in Figure 12-2 , it is the state when the leaf is just opened.

[0151] Continuing the foregoing process, Figure 12-3 , the leaf has been opened to the maximum, so that the two sides of the beam 1008 are flush with the left and right ends of the tumor 1007 slice. At this time, the coverage area of the Bragg peak has increased a lot, and the coverage area has expanded along the bottom edge of the tumor 1007 slice to both sides.

[0152] Continuing the foregoing process, as shown in Figure 12-4As shown, the coverage area of the Bragg peak is further increased, and the coverage area is shrunk along the upper edge of the tumor 1007 slice to the highest point of the tumor 1007 slice.

[0153] Continuing the foregoing process, as shown in Figure 12-5 As shown, the two leaves continue to move inwards and finally return to the closed state. The irradiation of one tumor 1007 slice is completed. The same process is performed for all pairs of leaves, and all tumor 1007 slices are irradiated in succession. The start and end irradiation times for each pair of leaves can be different.

[0154] The use of upper and lower leaves to irradiate alternately is to ensure that there is no leakage of radiation during the preparation stage before irradiation and after irradiation.

[0155] During the continuous irradiation process, the left upper leaf and the right lower leaf in the double-layer collimator play a conformal role.

[0156] The structural design of the present delivery system is also applicable to the conventional layer-by-layer irradiation method, in which the tumor 1007 is not sliced longitudinally but horizontally, and all leaves conform to the tumor slice from the bottom layer to the top layer while irradiating the tumor 1007 layer by layer. To increase the thickness of each layer, the energy continuous modulator 9 can slightly pull the Bragg peak on the beam end face.

[0157] Figure 12-6 Two special cases of tumors are listed, as shown in Figure 12-6 (a) As shown, the tumor has recesses on both sides at this time, in which case the foregoing continuous irradiation process remains unchanged; as shown in Figure 12-6 (b) As shown, the tumor 1007 has recesses on the top and bottom, and for this case, the tumor 1007 can be divided into left and right parts and irradiated twice. For more complex shapes, it can also be irradiated three or four times.

[0158] As shown in Figure 13 The multi-leaf collimator 13-1 connected to the ionization chamber 14 moves 200 mm upward from the lowest limit position, at which time the sides of the collimator edge leaves at the two positions are substantially parallel to the rays 1010 emitted by the point light source 1001, because the distance of the point light source 1001 from the isocenter plane 1002 is sufficiently far, ≧3000 mm. In this way, through the lifting design of the multi-leaf collimator (13-1), the terminal collimator of the conventional delivery system can be replaced.

[0159] In summary, the present embodiment achieves its purpose, namely:

[0160] 1. The present embodiment uses one energy continuous modulator to replace the binary energy modulator and the wringer-type modulator in the conventional beam-expanding delivery system, and cooperates with the multi-leaf collimator to achieve continuous irradiation;

[0161] 2. The use of a wedge absorber system and independent continuous irradiation of each pair of leaves replaces the range compensator of the traditional delivery system;

[0162] 3. The use of a retractable design of the multi-leaf collimator replaces the end collimator of the traditional beam expanding delivery system.

Claims

1. A medical particle accelerator broad-beam continuous irradiation beam delivery system, characterized by: It comprises ionization chamber group A (2), first scatterer system (3), second scatterer system (5), collimator A (7), ionization chamber group B (8), energy continuous modulator (9), wedge absorber system (10), collimator B (11), liftable multi-leaf collimator (13) and ionization chamber (14) arranged in sequence. The axis of the ionization chamber group A (2) and the ionization chamber group B (8) is coincident with the Y-axis; the geometric center line axis of the ionization chamber (14) is coincident with the Y-axis; The axis of the ionization chamber group A (2) or the ionization chamber group B (8) and the liftable multi-leaf collimator (13) passes through the collimator A (7) and the collimator B (11); the rays emitted at the point light source (1001) on the axis (Y-axis) are parallel to the four inner walls of the collimator A (7), the collimator B (11) and the liftable multi-leaf collimator (13), and the projection on the equicentral plane (1002) is a rectangle; The first scatterer system (3) and the second scatterer system (5) are arranged in sequence along the axis (Y-axis) of the ionization chamber group A (2) or the ionization chamber group B (8) to form a double scattering system; when the first scatterer system (3) and the second scatterer system (5) swing left and right, the axis of the first scatterer system (3) and the second scatterer system (5) is coincident with the axis (Y-axis) of the ionization chamber group A (2) or the ionization chamber group B (8); The energy continuous modulator (9) and the wedge absorber system (10) are arranged between the ionization chamber group B (8) and the collimator B (11) to adjust the energy of the beam emitted from the ionization chamber group B (8) before entering the collimator B (11); The second scatterer system (5) comprises n cylindrical second scatterers (5-1) with curved convex surfaces on the outer edge upper surfaces.

2. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 1, wherein: It further comprises a support frame, which comprises a base (1) composed of two vertically parallel thick plates, a mounting seat A (4), a mounting seat B (6) and a mounting seat C (12) arranged horizontally between the two plates of the base (1); The mounting seat A (4) is arranged on the upper part of the base (1) and is a horizontal mounting plate connected to the two plates of the base (1) at both ends; the ionization chamber group A (2) and the first scatterer system (3) are mounted above the mounting seat A (4); The mounting seat B (6) is arranged in the middle of the base (1) and is a horizontal mounting plate connected to the two plates of the base (1) at both ends; the second scatterer system (5) is mounted above the mounting seat B (6), and a space is provided between the second scatterer system (5) and the bottom surface of the mounting seat A (4); the collimator A (7) and the ionization chamber B (8) are sequentially mounted below the mounting seat B (6); The mounting base C (12) is arranged at the bottom of the base and is a horizontal mounting plate connected with the two plates of the base (1) respectively at two ends; the mounting base C (12) sequentially mounts the collimator B (11), the wedge-shaped absorber system (10) and the energy continuous modulator (9), the energy continuous modulator (9) is arranged below the ionization chamber B (8); the liftable multi-leaf collimator (13) and the ionization chamber (14) are sequentially arranged below the mounting base C (12).

3. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 2, wherein: The first scatterer system (3) comprises a group of n first scatterers (3-1) in the shape of circular thin plates with different thicknesses, and a moving device for moving the first scatterers (3-1) in a straight line in the front-back direction; The n first scatterers (3-1) are arranged in a horizontal direction with upper surfaces in a horizontal plane, and the center point of the plane is located at the position of the point light source (1001); Under the action of the moving device, the axis of a certain circular first scatterer (3-1) coincides with the beam emitted by the point light source (1001).

4. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 2, wherein: The energy continuous modulator (9) comprises a wedge-shaped absorber A (9-1) with an upward inclined surface and a downward horizontal surface, a wedge-shaped absorber base (9-2) with a rectangular hole, m wedge-shaped absorbers B (9-3) with upward inclined surfaces and downward horizontal surfaces, and a moving mechanism for moving the wedge-shaped absorbers B (9-3) in the left-right direction.

5. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 2, wherein: The liftable multi-leaf collimator (13) comprises a multi-leaf collimator (13-1) and an up-down moving mechanism for driving the multi-leaf collimator (13-1) to move up and down.

6. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 5, wherein: The moving mechanism comprises a linear moving mechanism and a linear driving mechanism; The linear moving mechanism comprises two linear guide rails, two groups of two sliders in each group, a corresponding number of sliding plates and cover plates, the two linear guide rails are mounted on the upper surface of the mounting base and are movably connected with the two groups of two sliders in each group respectively; the two groups of two sliders in each group are connected with the sliding plates; and the cover plates are connected with the sliding plates.

7. The medical particle accelerator broad-beam continuous irradiation beamlet delivery system of claim 6, wherein: The wedge-shaped absorber system (10) comprises N groups of two rotatable wedge-shaped absorbers C (10-1) with inclined upper surfaces and horizontal lower surfaces, and a wedge-shaped absorber translation and rotation mechanism (10-2) for driving the rotatable wedge-shaped absorbers C (10-1) to rotate and move stably.

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