WO2005004168A1

WO2005004168A1 - Range compensator and heavy charged particle beam irradiation system

Info

Publication number: WO2005004168A1
Application number: PCT/JP2004/009318
Authority: WO
Inventors: Nobuyuki Kanematsu
Original assignee: National Institute Of Radiological Sciences
Priority date: 2003-07-01
Filing date: 2004-07-01
Publication date: 2005-01-13
Also published as: JP2005024475A

Abstract

A range compensator and a heavy charged particle beam irradiation system capable of automatically adjusting the range of radiant rays toward a target for each target to reduce the treatment time and cost. A heavy charge particle beam irradiation system (heavy charge particle beam cancer treatment system) (11) has a range compensator (12) for adjusting the range of an irradiation beam (1) toward a target (4) by absorbing the energy of the irradiation beam (1). The range compensator (12) comprises an energy-absorbing layer (14) that is composed of leaves (13) for absorbing the energy of the irradiation beam (1) and actuators (15) for independently and separately moving the leaves (13) back/forth along the track of the irradiation beam (1). Each leaf (13) is a rectangular plate. The leaves (13) are arranged parallel in the Y direction perpendicular to the length direction (X direction).

Description

Specification

Range compensator and heavy charged particle beam irradiation device

Technical field

The present invention relates to a range compensator and a heavy-charged particle beam irradiator that three-dimensionally control the range (stop position) of radiation such as a heavy particle beam, a proton beam, and an ion beam to a target.

Background art

[0002] A heavy particle beam cancer treatment apparatus will be described as an example of a conventional heavy charged particle beam irradiation apparatus, and will be described with reference to Figs. Fig. 15 is a schematic diagram showing the overall configuration of a conventional heavy ion beam cancer treatment device. Fig. 16 is an enlarged view of the irradiation part and the patient of the heavy ion beam cancer treatment device in Fig. 15. It is sectional drawing.

In FIG. 15, heavy ions such as carbon ions (C ⁶⁺ ) generated by a radiation source (not shown) are converted into an irradiation beam 1 as radiation from an accelerator (not shown) to a bed 2. Irradiation is directed at target 4, the tumor site in patient 3 lying aside. In addition, before the irradiation beam 1 is irradiated on the target 4 in the patient 3, the irradiation field expansion device 5, the range modulation device 6, the range attenuation device 7, the multi-leaf collimator device 8, and the range compensation By sequentially passing through the filter 9 and the like, the dose distribution is processed so as to have an effective diameter, thickness, and maximum range corresponding to the three-dimensional shape of the target 4, and the target 4 is irradiated.

[0004] Here, the irradiation field enlarging device 5 is composed of electromagnets 5A, 5A and a scatterer 5B.

1 is to expand the cross-sectional shape. The range modulator 6 is a device formed by cutting an aluminum plate or the like into a ridge shape, and expands the irradiation beam 1 in the irradiation direction (vertical direction). In addition, the range damping device 7 combines multiple energy absorbing plates 7A, 7B, 7C, 7D, 7E, and 7F with different thicknesses to uniformly shorten the range of the irradiation beam 1 to the target 4. It is to let.

Further, as shown in FIG. 16, the multi-leaf collimator device 8 is configured by arranging a plurality of rows of a pair of metal plates 8A, 8A that are detachably opposed to each other (for example, see Patent Reference 1). Then, the multi-leaf collimator device 8 separates and approaches the metal plates 8A, 8A facing each other in the longitudinal direction by using an actuator (not shown), thereby forming each metal plate 8A. An opening 8B corresponding to the cross-sectional shape of the target 4 is formed therebetween. Therefore, the irradiation beam 1 is processed into a beam shape corresponding to the target 4 and irradiates the target 4 by passing through the opening 8B.

[0006] The three-dimensional shape of the range compensation filter 9 is designed so that the range (stop position) of the irradiation beam 1 with respect to the target 4 matches the shape of the target 4 on the bottom side in the depth direction. I have. Therefore, it is possible to prevent exposure to normal tissue deeper than the target 4. In addition, by performing such irradiation on the same target 4 from a plurality of directions (for example, a vertical direction and a horizontal direction), it is possible to form an irradiation region that matches the three-dimensional shape of the target 4. The range compensation filter 9 is also called a bolus, and is described in Non-Patent Document 1, for example.

Patent Document 1: Japanese Patent Publication No. 2001-509898 (page 9, FIG. 2)

Non-Patent Document 1: “Review of Science Instrument” (USA) (August 1993), Vol. 64, No. 8, P2072

Disclosure of the invention

Problems to be solved by the invention

[0007] By the way, in the treatment using the heavy ion beam cancer treatment apparatus according to the above-described conventional technique, a high dose even to a deep normal tissue beyond the target 4 which is a tumor can be obtained unless an appropriate range compensation filter 9 is used. Irradiation with the irradiation beam 1 having the above causes a side effect. However, an appropriate range compensation filter 9 differs depending on the shape of the target 4 in the patient 3, so that a filter that is suitable for each patient 3 and further for each direction of irradiation to the patient 3 must be manufactured individually. No. Therefore, the following problem occurs.

[0008] That is, when manufacturing the range compensation filter 9, an expensive numerically controlled machine tool must be used in order to perform a cutting process on a plastic material or the like as a base material. In order to inspect the dimensional accuracy of the range compensating filter 9 after processing, replace the range compensating filter 9, and store and discard the range compensating filter 9, A lot of manual work and management work are required, and when such a range compensation filter 9 is used, the time and cost required for treatment are not only high but also cause a human error due to manual work. There is.

[0009] In view of the above problems, the present invention automatically adjusts the range of radiation to a target for each target. It is an object of the present invention to provide a range compensator and a heavy charged particle beam irradiation device capable of reducing the time and cost required for treatment.

Means for solving the problem

[0010] The present invention is designed to solve the above-mentioned problems, and the invention described in claim 1 is

A range compensating device that is provided in a path of radiation irradiated from the radiation source toward the target and adjusts the range of the radiation to the target by absorbing the energy of the radiation; A range compensating device comprising: a plurality of energy absorbers for absorbing energy; and an actuator for moving each of the energy absorbers separately and independently toward the path of the radiation.

[0011] According to the range compensating device of claim 1, when the radiation passes through the energy absorber, the energy of the radiation is weakened, and the range of the radiation to the target can be set small. On the other hand, radiation directly radiated to the target without passing through the energy absorber does not have its energy weakened by the energy absorber, so that the range of the radiation to the target can be set to be large. .

[0012] Accordingly, by independently moving each energy absorber toward the path of the radiation using an actuator, the range of the radiation in the depth direction of the target can be appropriately adjusted according to the shape of the target. It can be adjusted automatically, for example, when irradiating the affected area targeted by the patient, unnecessary radiation to normal tissue can be prevented.

[0013] The invention according to claim 2 is characterized in that the energy absorber is a leaf having an elongated plate-like body strength, and the energy absorber is formed by arranging the leaves in a plurality of rows in a plate shape. Is a range compensating device.

[0014] According to the range compensator according to claim 2, the shape of the opening formed between the leaves is achieved by separately moving each leaf constituting the energy absorbing layer toward the path of radiation. The range of radiation to the target can be adjusted more precisely according to the three-dimensional shape of the target.

[0015] The invention according to claim 3 is a range compensating device, wherein a plurality of energy absorbing layers are arranged along a path of radiation.

[0016] According to the range compensator of claim 3, each resource is provided for each energy absorption layer. By moving the probe, the range of the radiation to the target can be more finely adjusted.

[0017] The invention according to claim 4 is characterized in that the leaf of at least one of the plurality of energy absorbing layers is moved in a direction different from the direction of the leaves of the other energy absorbing layers. Range compensator.

[0018] According to the range compensating device of claim 4, at least one of the plurality of energy absorbing layers is moved in a direction different from that of the leaves of the other energy absorbing layers. By doing so, the range of radiation to the target can be adjusted with high accuracy in accordance with the three-dimensional shape of the target.

[0019] In the invention according to claim 5, the leaf of at least one of the plurality of energy absorbing layers is formed to have a thickness different from that of the leaves of the other energy absorbing layers. A range compensating device characterized by the following.

[0020] According to the invention set forth in claim 5, the radiation energy after passing through the leaf depends on whether the radiation has passed through a leaf having a small thickness or a leaf having a large thickness. Ghee can be changed.

[0021] The invention according to claim 6 is that the leaf of at least one of the plurality of energy absorbing layers is made of a material having an energy absorptivity different from the leaves of the other energy absorbing layers. A range compensating device characterized by being formed.

[0022] According to the invention set forth in claim 6, the radiation passes through the leaf having a small energy absorption rate and the radiation having passed through the leaf having a large energy absorption rate. Can change the energy of the radiation.

[0023] In the invention according to claim 7, the leaf of at least one of the plurality of energy absorbing layers is formed to have a plate width different from the leaf of the other energy absorbing layer. A range compensating device characterized by the following.

[0024] According to the invention of claim 7, by using a combination of a leaf having a small plate width and a leaf having a large plate width, the range of radiation to the target can be adjusted with high accuracy in accordance with the three-dimensional shape of the target. Can be adjusted.

[0025] In the invention according to claim 8, the energy absorbing layer has a pair of leaves each having a length corresponding to each row. A range compensating device characterized in that the range compensating device is configured so as to be opposed to each other, to be separated from each other, and to approach each other.

[0026] According to the invention described in claim 8, the pair of leaves facing each other in the longitudinal direction are separated and approached to each other by using an actuator, so that an opening formed between the leaves is formed. It becomes possible to change the shape more closely according to the three-dimensional shape of the target.

[0027] The invention described in claim 9 is a range compensating apparatus characterized in that an obliquely tapered surface is formed on a leaf.

[0028] According to the invention as set forth in claim 9, the energy of the radiation after passing can be changed in accordance with the position of the radiation passing through the tapered surface formed on the leaf, and the range of the radiation can be adjusted to the target range. Can be set to a smoother shape that matches the shape of.

[0029] The invention described in claim 10 is a range compensating device, wherein the energy absorber is advanced and retracted during irradiation of radiation.

[0030] According to the invention set forth in claim 10, by moving the energy absorber back and forth during the irradiation of the radiation, the range of the radiation with respect to the target is adjusted with higher accuracy in accordance with the three-dimensional shape of the target. be able to.

[0031] The invention according to claim 11 is a heavy charged particle beam irradiation device comprising a range compensation device.

According to the eleventh aspect of the present invention, a heavy charged particle beam irradiation device having a range compensating device is used instead of the range compensating filter described in the related art, so that the heavy charged particle beam is used. The efficiency of treatment by the irradiation device can be increased.

The invention's effect

[0033] As described in detail above, according to the first aspect of the present invention, since a plurality of energy absorbers are moved independently and independently toward the path of radiation by the actuator, each energy absorber is used. By using an actuator to move back and forth toward the path of radiation, the range of radiation to the target can be automatically changed for each target according to the position and shape of the target, and the irradiation area that matches the three-dimensional shape of the target Can be formed. Therefore, it is not necessary to separately manufacture or replace the range compensation filter as described in the prior art for each patient target, or to perform storage, disposal, etc., thereby greatly reducing the time and cost required for treatment. Xiao | J can be reduced.

[0034] In the invention according to claim 2, since the energy absorbing layer is formed by arranging a plurality of elongated plate-shaped body leaves as energy absorbers in a plate shape, the leaves constituting the energy absorbing layer are irradiated with radiation. By separately moving toward the path, the shape of the opening formed between each leaf can be changed more finely, and the range of radiation to the target can be adjusted more precisely according to the three-dimensional shape of the target And the performance of the range compensator can be improved.

[0035] In the invention according to claim 3, since a plurality of energy absorbing layers are arranged along the path of radiation, the range of radiation to the target can be reduced by moving each leaf for each energy absorbing layer. More fine adjustment is possible, and the performance of the range compensator can be further enhanced.

[0036] The invention according to claim 4 has a configuration in which the leaf of at least one of the plurality of energy absorbing layers is moved in a direction different from that of the leaves of the other energy absorbing layers. The range of the radiation to the target can be adjusted with high accuracy, and the performance of the range compensator can be further improved.

In the invention according to claim 5, the leaf of at least one of the plurality of energy absorbing layers is formed to have a thickness different from that of the leaves of the other energy absorbing layers. The radiation energy after passing through the leaf can be changed between the case where the radiation passes through a leaf with a small thickness and the case where the radiation passes through a leaf with a large thickness. Can be adjusted with high precision.

[0038] In the invention according to claim 6, the leaf of at least one of the plurality of energy absorbing layers is made of a material having a different energy absorption rate from the leaves of the other energy absorbing layers. Since the radiation has been formed, the energy of the radiation after passing through the leaf can be changed depending on whether the radiation passes through a leaf having a small energy absorption rate or a leaf having a large energy absorption rate, The range of radiation to the target can be adjusted with high precision.

[0039] In the invention according to claim 7, the leaf of at least one of the plurality of energy absorbing layers has a plate width different from the leaf of the other energy absorbing layer. By using a combination of a leaf with a small plate width and a leaf with a large plate width, the range of radiation to the target can be adjusted with high accuracy in accordance with the three-dimensional shape of the target.

[0040] In the invention according to claim 8, the energy absorbing layer is configured such that a pair of leaves are opposed to each other in the length direction and separated from each other and approach each other in each row. By separating and approaching a pair of leaves with each other using an actuator, the shape of the opening formed between the leaves can be changed more finely in accordance with the three-dimensional shape of the target. The range of radiation can be adjusted with high precision.

According to the ninth aspect of the invention, since the tapered surface that is obliquely inclined is formed on the leaf, the energy of the radiation after passing therethrough depends on the position where the radiation passes through the tapered surface formed on the leaf. Can be changed, and the range of the radiation can be set to a smoother shape that matches the shape of the target.

[0042] The invention according to claim 10 has a configuration in which the energy absorber moves forward and backward during irradiation of radiation, so that the range of radiation to the target can be adjusted with higher precision in accordance with the shape of the target. Can be.

The invention according to claim 11 uses a heavy charged particle beam irradiation device having a range compensating device instead of the range compensating filter described in the related art, so that the heavy charged particle beam is used. The efficiency of treatment by the irradiation device can be increased.

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment)

An example in which the range compensating device and the heavy charged particle beam irradiation device according to the first embodiment of the present invention are used in a heavy particle beam cancer treatment device will be described with reference to FIGS. 1 to 3.

FIG. 1 is a partially enlarged cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment, and FIG. 2 shows a range compensating apparatus shown by an arrow in FIG. FIG. 3 is a front view as viewed from the direction Π-Π. FIG. 3 is a partial perspective view showing a leaf in FIG. 2 in an enlarged manner. In FIGS. 1 and 2, the X direction indicates the width direction of the patient 3, the Y direction indicates the body axis direction of the patient 3, and the Z direction indicates the axial direction (irradiation direction) of the irradiation beam 1. RU As shown in FIG. 1, the heavy ion beam cancer treatment apparatus 11 applies the irradiation beam 1 to the patient 3 by the opening 8B formed between the metal plates 8A, 8A, almost in the same manner as the above-mentioned conventional technology. A multi-leaf collimator 8 for processing into a beam shape corresponding to the target 4, and provided at a location downstream of the multi-leaf collimator 8 in the path of the irradiation beam 1 to absorb the energy of the irradiation beam 1 It has a range compensator 12 for adjusting the range with respect to the target 4 and a bed 2 on which the patient 3 lies.

[0047] Further, as shown in FIG. 2, the range compensator 12 includes an energy unit comprising a plurality of leaves 13, 13, ... as energy absorbers for absorbing the energy of the irradiation beam 1 (see Fig. 1). It is composed of an absorption layer 14 and a plurality of actuators 15, 15,... For independently and independently moving the leaves 13 of the energy absorption layer 14 toward the path of the irradiation beam 1, respectively.

Here, each leaf 13 constituting the energy absorption layer 14 is formed as a rectangular plate having a certain plate thickness by using, for example, a metal material, a plastic material, or the like (see FIG.

3). The leaf 13 is, for example, a plate-like body having a width of 2 cm, a thickness of lcm, and a length of 40 cm. As shown in FIG. 2, two leaves face each other in the length direction (X direction) and a plurality of rows in the Y direction. (16 rows) They are arranged side by side. Further, the actuator 15 includes, for example, a rack attached to the leaf 13, a pin connected to the rack, a motor for rotating the pin, and a control mechanism for controlling the rotation of the motor (a shift mechanism). (Also not shown). The actuator 15 is configured to move the leaf 13 integrated with the rack in the X direction by rotating the pion using a motor and a control mechanism.

For this reason, as shown in FIG. 2, a pair of leaves 13 and 13 facing each other in the X direction are moved in the X direction by an actuator 15 so as to be separated from and approach to each other. Form part 16. In other words, the range compensator 12 automatically changes the opening 16 to various shapes according to the three-dimensional shape of the target 4 by individually operating each leaf 13 using the actuator 15. is there.

Next, the operation of the heavy ion beam cancer treatment apparatus 11 will be described.

First, the three-dimensional shape of the target 4 of the patient 3 is measured in advance using X-ray CT, MRI, or the like. Then, according to the measured shape of the target 4, each leaf 13 is individually moved by the actuator 15. It is operated individually to change the shape of the opening 16. Then, as shown in FIG. 1, the irradiation beam 1 is irradiated toward the target 4 of the patient 3. The irradiation beam 1 passes through the range compensator 12 in the middle of the path. At this time, the component passing through the opening 16 of the energy absorbing layer 14 reaches deep inside the body, while the component passing through each leaf 13 of the energy absorbing layer 14 absorbs a certain amount of energy by the leaf 13. The range becomes shallower by the minute. In other words, it is possible to compensate by changing the range of the irradiation beam 1 to the target 4 of the patient 3 in two stages.

As described above, according to the present embodiment, by moving each leaf 13 toward and away from the irradiation beam 1 using the actuator 15, the irradiation area (dose (Distribution) can be formed, exposure to normal tissue deeper than the target 4 can be prevented, and the performance, reliability, etc. of the heavy ion beam cancer treatment device 11 can be improved.

According to the present embodiment, since each leaf 13 is moved using the actuator 15, the shape of the opening 16 is adjusted for each patient 3 according to the position and shape of the target 4. It can be changed automatically as appropriate. Therefore, it is not necessary to manufacture or replace the range compensation filter for each patient 3 as described in the prior art, or to store, dispose, etc., and to significantly reduce the time and cost required for treatment. Can be.

(Second Embodiment)

Next, FIGS. 4 to 6 show a second embodiment of the present invention. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 4 is an enlarged partial cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment, and FIG. 5 shows a range compensating apparatus shown by an arrow in FIG. FIG. 5 is a front view as viewed from the V-V direction. FIG. 6 is a partial perspective view showing a leaf in FIG. 5 in an enlarged manner.

As shown in FIG. 4, the heavy ion beam cancer treatment apparatus 21 has a multi-leaf collimator apparatus 8, a range compensator 22, and a bed 2 in substantially the same manner as in the first embodiment. . However, as shown in FIGS. 4 to 6, the range compensator 22 used in the present embodiment includes a first energy absorbing layer 24 including a plurality of leaves 23, 23,. The second consisting of It is different from that of the first embodiment in that it is constituted by an energy absorbing layer 26.

Here, the first energy absorbing layer 24 and the second energy absorbing layer 26 are stacked along the path of the irradiation beam 1 as shown in FIG. In the first energy absorbing layer 24, as shown in FIG. 5, the leaves 23 are arranged in a plurality of rows in the Y direction so as to face each other in the X direction. In other words, the leaves 23 are arranged in, for example, a 16-row plate shape in a direction orthogonal to the path of the irradiation beam 1 as a set of two leaves. Also, the second energy absorbing layers 26 are arranged in a 16-row plate shape in a direction orthogonal to the path of the irradiation beam 1 as a set of two sheets. Each leaf 23 and each leaf 25 are individually and independently moved in the X direction by an actuator 27 and an actuator 28 (see FIG. 4).

In the present embodiment configured as described above, the first energy absorbing layer 24 and the second energy absorbing layer 26 are arranged along the path of the irradiation beam 1, so that the first The shape of the opening 29 of the energy absorbing layer 24 and the shape of the opening 30 of the second energy absorbing layer 26 can be individually changed. Therefore, it is possible to compensate by changing the range of the irradiation beam 1 to the target 4 of the patient 3 at a maximum of four steps. In other words, the irradiation beam 1 passes through the openings 29 and 30, passes only through the energy absorption layer 24, passes through only the energy absorption layer 26, and passes through both energy absorption layers 24 and 26. In some cases, the range of the irradiation beam 1 is different in each case. Therefore, the range of the irradiation beam 1 with respect to the target 4 can be more finely adjusted, and the performance, reliability, and the like of the heavy ion beam cancer treatment apparatus 21 can be further improved.

(Third Embodiment)

Next, FIGS. 7 and 8 show a third embodiment of the present invention. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 7 is an enlarged partial cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment, and FIG. 8 shows a range compensator shown by an arrow in FIG. VIII- It is a rear view as seen from the VIII direction.

As shown in FIG. 7, the heavy ion beam cancer treatment apparatus 31 is substantially the same as the second embodiment, It has a multi-leaf collimator 8, a range compensator 32 and a bed 2. As shown in FIGS. 7 and 8, the range compensator 32 includes a first energy absorption layer 34 including a plurality of leaves 33, 33, and a first energy absorption layer 34 including a plurality of leaves 35, 35,. The two energy absorbing layers 36 and are stacked along the path of the irradiation beam 1.

As shown in FIG. 8, the leaves 33 of the first energy-absorbing layer 34 are opposed to each other in the X direction as a set of two sheets, and are arranged in a plurality of rows (16) in the Y direction. Row), whereas the leaves 35 of the second energy absorbing layer 36 are arranged in a row and are opposed to each other in the Y direction as a pair, and are arranged in a plurality of rows (16 rows) in the X direction. It differs from the second embodiment in that it is provided.

In the present embodiment configured as described above, the leaf 33 of the first energy absorbing layer 34 can be moved in the X direction by the actuator 37, and the leaf 35 of the second energy absorbing layer 36 is moved to the actuator 35. Since it can be moved in the Y direction by 38, the openings 39, 40 of the energy absorption layers 34, 36 can be individually changed in the X, Y directions, respectively, and the range of the irradiation beam 1 can be further finely adjusted. It is possible to do. Therefore, by using the energy absorbing layers 34 and 36, the range of the irradiation beam 1 can be more matched even with, for example, a crescent-shaped target having a depression in the center.

[0063] Further, since the leaves 33 of the first energy absorption layer 34 are arranged to move in the X direction, and the leaves 35 of the second energy absorption layer 36 are arranged to move in the Y direction, The actuator 37 attached to the leaf 33 and the actuator 38 attached to the leaf 35 do not interfere with each other, and the layout of these actuators 37, 38 can be easily designed.

(Fourth Embodiment)

Next, FIG. 9 shows a fourth embodiment of the present invention. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 9 is a partially enlarged cross-sectional view showing an irradiated part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment. As shown in FIG. 9, the heavy ion beam cancer treatment device 41 includes a multilobal collimator device 8, a range compensator 42, and a bed 2, almost in the same manner as in the second embodiment. Yes. The range compensator 42 includes a first energy-absorbing layer 44 including a plurality of leaves 43, 43,... And a second energy-absorbing layer 44 including a plurality of leaves 45, 45,. The energy absorption layer 46 is laminated along the path of the irradiation beam 1. By moving the leaves 43 and 45 independently by actuators 47 and 48, openings 49 and 50 are formed in the first and second energy absorbing layers 44 and 46, respectively.

However, the range compensating device 42 used in the present embodiment is different from the thickness of the leaf 43 constituting the first energy absorbing layer 44 in the thickness of the leaf 45 constituting the second energy absorbing layer 46. Is different from that of the second embodiment in that it is also formed large.

In the present embodiment configured as described above, the range of the irradiation beam 1 is adjusted by using the leaf 45 having a large thickness for a portion where the shape change in the depth direction of the target 4 is large. At the same time, the range of the irradiation beam 1 can be adjusted using a leaf 43 with a small thickness for the part where the shape change in the depth direction of the target 4 is small, so that the irradiation beam 1 Range can be more closely matched.

(Fifth Embodiment)

Next, FIG. 10 shows a fifth embodiment of the present invention. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 10 is a partially enlarged cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment. As shown in FIG. 10, the heavy ion beam cancer treatment apparatus 51 has a multilobal collimator apparatus 8, a range compensator 52, and a bed 2, almost similarly to the second embodiment. The range compensator 52 includes a first energy-absorbing layer 54 including a plurality of leaves 53, 53,... And a second energy-absorbing layer 54 including a plurality of leaves 55, 55,. The energy absorption layer 56 is laminated along the path of the irradiation beam 1. The leaves 53 and 55 are moved independently by the actuators 57 and 58 to form openings 59 and 60 in the first and second energy absorbing layers 54 and 56, respectively.

[0070] However, in the range compensating device 52 used in the present embodiment, the leaves 53 constituting the first energy absorbing layer 54 are formed using a plastic material or the like having a relatively small energy absorption rate. On the other hand, the leaf 55 forming the second energy absorption layer 56 The third embodiment differs from the second embodiment in that it is formed using a metal material or the like having a relatively large energy absorption.

[0071] Also in the present embodiment configured as described above, for a portion where the shape change in the depth direction of the target 4 is large, the flight of the irradiation beam 1 is performed using the leaf 55 having a relatively large energy absorption rate. In addition to being able to adjust the range of the irradiation beam 1 for the part where the shape change in the depth direction of the target 4 is small, the range of the irradiation beam 1 can be adjusted using the leaf 53 whose energy absorption is relatively small. On the other hand, the range of the irradiation beam 1 can be made more consistent, and substantially the same effect as in the fourth embodiment can be obtained.

(Sixth Embodiment)

Next, FIG. 11 and FIG. 12 show a sixth embodiment of the present invention. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 11 is a partially enlarged cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the present embodiment, and FIG. 12 is an enlarged view of a leaf in FIG. It is a perspective view.

As shown in FIG. 11, the heavy ion beam cancer treatment apparatus 61 includes a multilobal collimator apparatus 8, a range compensator 62, and a bed 2. The range compensator 62 includes a first energy absorbing layer 64 composed of a plurality of leaves 63, 63,... Arranged along the Y direction, as shown in FIG. A second energy absorption layer 66 composed of a plurality of leaves 65, 65,... And a third energy absorption layer 68 composed of a plurality of leaves 67, 67,. They are sequentially stacked along the path of beam 1. By moving the leafs 63, 65, 67 separately in the Y direction independently by an actuator (not shown), the first, second, and third energy absorbing layers 64, 66, 68 have Openings 69, 70, 71 are formed.

Here, among the leaves 63, 65, 67, the plate width of the leaf 65 is formed smaller by J // than the plate width of the leaves 63, 67. Also, the leaf 63 and the leaf 67 are, for example, a plate of the leaf 65 so that the seam along the Y direction between the leaves 63 and 63 does not match the seam along the Y direction between the leaves 67 and 67. They are arranged alternately in the X direction by the width!

As described above, in the present embodiment, the leaves 65 constituting the second energy absorption layer 66 Since the plate width is formed smaller than the plate widths of the leaves 63, 67 constituting the first and third energy absorbing layers 64, 68, the target 4 has a large change in the shape (depth) in the width direction. Adjusts the range of the irradiation beam 1 using a leaf 65 with a small division width, that is, a small plate width, and divides the target 4 in the part where the shape (depth) change in the width direction is small. The range of the irradiation beam 1 can be adjusted by using the wide leaves, that is, the leaves 63 and 67 having a large plate width, so that the range of the irradiation beam 1 can be more closely matched to the target 4. it can.

[0077] Also, by shifting the gap between the leaves 63, 63 relatively to the gap between the leaves 67, 67, the irradiation beam 1 is unlikely to be emitted between the leaves 67, 67 and between the leaves 65, 67. Even if the radiation beam 1 passes through the gap between the target beams 4, the irradiation beam 1 hits the leaf 63, so that the phenomenon that the irradiation beam 1 penetrates the leaf 63 can be avoided, and the irradiation beam on the target 4 can be avoided.

The irradiation area of 1 can be made a gentle shape close to the shape of the target 4.

(Seventh Embodiment)

Next, FIG. 13 shows a seventh embodiment of the present invention. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 13 is a partially enlarged cross-sectional view showing the irradiated part and the patient of the heavy ion beam cancer treatment apparatus according to the present embodiment. As shown in FIG. 13, the heavy ion beam cancer treatment apparatus 81 includes a multilobal collimator apparatus 8, a range compensator 82, and a bed 2. The range compensator 82 includes a first energy absorbing layer 84 composed of a plurality of leaves 83, 83,... Arranged along the X direction, and a plurality of leaves 85, 85 arranged along the Υ direction. , A second energy absorbing layer 86 composed of a plurality of leaves 87, 87, arranged in the X direction, and a third energy absorbing layer 88 composed of a plurality of leaves 87, 87, arranged in the X direction. A fourth energy absorbing layer 90 composed of a plurality of leaves 89, 89,... Is sequentially stacked along the path of the irradiation beam 1.

[0080] Further, the leaves 83, 85, 87, and 89 are individually and independently moved by using actuators 91, 92, and the like, so that the first, second, third, and fourth energy absorbing layers 84, 89 can be moved. At 86, 88, 90, openings 93, 94, 95, 96 are formed. In addition, the range compensator 82, which has the same energy as the energy absorbing layers 84, 86, 88, 90 and the actuators 91, 92, is a multi-leaf collimator. It is located upstream of the irradiation beam 1 from the device 8.

In the present embodiment configured as described above, during irradiation of the irradiation beam 1, some or all of the leaves 83, 85, 87, and 89 are routed through the irradiation beam 1 based on a previously prepared program or the like. The irradiation amount of the irradiation beam 1 in a specific range passing through the range compensator 82 can be changed during the irradiation of the irradiation beam 1 by moving back and forth. This makes it possible to make the range of the irradiation beam 1 more consistent with the target 4. For example, the shape of the bottom of the range of the irradiation beam 1 having a stepped shape in FIG. 13 may be changed to a gentle continuous curved shape. Further, the range of the irradiation beam 1 can be finely adjusted by compensating for the shortage of the number of layers (the number of layers) of the leaves 83, 85, 87, and 89. Further, since it is not necessary to replace the range compensating device 82 for each patient 3, the range compensating device 82 is located on the downstream side of the irradiation beam 1 from the multi-leaf collimator device 8 as in the prior art, that is, at a location where replacement is easy. This eliminates the necessity of arrangement, and facilitates layout design and the like of the range compensator 82.

(Eighth Embodiment)

Next, FIG. 14 shows an eighth embodiment of the present invention. Note that, in the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

FIG. 14 is a partially enlarged cross-sectional view showing the irradiated part and the patient of the heavy ion beam cancer treatment apparatus according to the present embodiment. As shown in FIG. 14, the heavy ion beam cancer treatment apparatus 101 has a multilobal collimator apparatus 8, a range compensator 102, and a bed 2, almost in the same manner as in the second embodiment. The range compensating device 102 includes a first energy absorbing layer 104 including a plurality of leaves 103, 103,... And a second energy absorbing layer 104 including a plurality of leaves 105, 105,. And the energy absorbing layer 106 are laminated along the path of the irradiation beam 1. In addition, by moving the leaves 103 and 105 separately and independently by the actuators 107 and 108, openings 咅 109 and 110 are formed in the first and second energy absorbing layers 104 and 106.

However, the range compensating device 102 used in the present embodiment is configured such that the distal ends of the leaves 103, 105 located on the openings 109, 110 are formed as tapered surfaces 103A, 105A that are obliquely inclined. Therefore, the second embodiment is different from the second embodiment. [0085] In the present embodiment configured as above, the distal ends of leaves 103 and 105 are formed as tapered surfaces 103A and 105A, so that the number of energy absorbing layers 104 and 106 (the number of layers) is reduced. Even if the distance is eliminated, the range of the irradiation beam 1 can be set to a smoother shape matching the shape of the target 4 by the tapered surfaces 103A and 105A, and the performance of the range compensator 102 can be further enhanced. .

[0086] In the first embodiment, the case where the range compensating device 12 is fixedly attached to the heavy ion beam cancer treatment device 11 has been described as an example, but the present invention is not limited to this. Without limitation. For example, a mechanism for rotating the range compensator 12 as shown by arrow A in FIG. 1 may be provided.In this case, the range of the irradiation beam 1 with respect to the target 4 can be further finely adjusted. it can. This is the same for the second to eighth embodiments.

In the first embodiment, an example has been described in which the range compensating device 12 is arranged on the downstream side of the irradiation beam 1 with respect to the multi-leaf collimator device 8. However, the present invention is not limited to this. For example, similarly to the seventh embodiment, the range compensator 12 may be provided on the upstream side of the irradiation beam with respect to the multi-leaf collimator 8. This is the same for the second to sixth and eighth embodiments.

In the seventh embodiment, the case where the range compensating device 82 is configured by stacking the four energy absorbing layers 84, 86, 88, and 90 has been described as an example. The range compensator 82 may be configured by laminating more than one.

Further, in the first embodiment, the case where a rack, a pin and a motor are used as the actuator 15 has been described as an example, but the present invention is not limited to this, for example, in the X direction or the Y direction. The actuator may be configured by a cylinder, a linear motor, etc. which can be extended and retracted. Further, a belt, a pulley, and a motor may be used in combination, or a screw, a screw, and a motor may be used in combination. Further, the position of each leaf can be detected directly on the leaf or by attaching an encoder to the cylinder or motor and counting the pulses generated from the encoder. As a guide mechanism (not shown) for supporting the movement of the leaf, a ball re-avering may be used, a guide member for supporting the leaf slidably or the like may be used, and there is no particular limitation. This is the same for the second to eighth embodiments. Further, in the first embodiment, as shown in FIG. 4, a case in which the first energy absorbing layer 24 and the second energy absorbing layer 26 are brought into abutment (surface contact) with each other is described. Although described as an example, the present invention is not limited to this. For example, the first energy absorbing layer 24 and the second energy absorbing layer 26 are arranged at intervals in the irradiation direction of the irradiation beam 1. The configuration is also good. This is the same also in the second to eighth embodiments.

In the first embodiment, as shown in FIG. 6, each of the leaves 23, 23, the leaves 25, 25, and the leaves 23, 25, which are adjacent to each other, have a gap force between them. The case where the leaves 23 and 25 are arranged in close contact with each other has been described as an example, but the present invention is not limited to this. For example, between the adjacent leaves 23 and 23, the leaves 25 and 25 , One of the opposing surfaces (contact surfaces) between the leaves 23 and 25 is provided with a concave groove along the X-axis direction, and the other opposing surface (contact surface) is provided with a convex portion. It is good also as a structure slidably fitted in a concave groove. This is the same for the second to eighth embodiments.

[0092] In the third embodiment, the first energy absorbing layer 34 and the second energy absorbing layer 36 are arranged such that the direction of movement of the leaf 33 and the direction of movement of the leaf 35 are orthogonal to each other by 90 degrees. Although the configuration in which the layers are stacked is described as an example, the configuration may be such that, for example, the reciprocating direction of the leaf 33 and the reciprocating direction of the leaf 35 intersect at an angle other than 90 degrees (eg, 60 degrees, 30 degrees).

[0093] Further, in the first embodiment, the case where a plurality of leaves 13 are used as an energy absorber has been described as an example. However, the present invention is not limited to this. For example, a plurality of leaves 13 may be used. 13 can be configured as one and used as one leaf. This is the same for the second to eighth embodiments.

In the second embodiment, the case where the openings 29 and 30 are formed using all the energy absorbing layers 24 and 26 has been described as an example. However, the present invention is not limited to this. The opening 29 or the opening 30 may be formed by moving only the necessary energy absorbing layer according to the irradiation conditions. This is the same for the third to eighth embodiments.

[0095] Further, in the first embodiment, the case where two leaves 13, 13 are arranged side by side for each row of the energy absorbing layer 14 has been described as an example. For example, a configuration in which one leaf is provided for each row of the energy absorbing layer 14 or a configuration in which three or more leaves are provided may be employed. This is the second to eighth form of implementation. The situation is the same.

In the first embodiment, the case where the energy absorbing layer 14 is configured by arranging the leaves 13 in 16 rows has been described as an example. However, the present invention is not limited to this. They may be arranged or 15 rows or less. This is the same for the second to eighth embodiments.

Brief Description of Drawings

FIG. 1 is a partially enlarged cross-sectional view showing an irradiation part and a patient of a heavy ion beam cancer treatment apparatus according to a first embodiment of the present invention.

FIG. 2 is a front view of the range compensator as viewed from the directions indicated by arrows in FIG. 1;

FIG. 3 is a partial perspective view showing a leaf in FIG. 2 in an enlarged manner.

FIG. 4 is a partially enlarged cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus according to the second embodiment of the present invention.

FIG. 5 is a front view of the range compensator as viewed from the direction indicated by arrows VV in FIG. 4.

FIG. 6 is a partial perspective view showing a leaf in FIG. 5 in an enlarged manner.

FIG. 7 is a partially enlarged cross-sectional view showing an irradiated part and a patient of a heavy ion beam cancer treatment apparatus according to a third embodiment of the present invention.

FIG. 8 is a rear view of the range compensator as viewed in the direction indicated by arrows VIII-VIII in FIG. 7.

FIG. 9 is a partially enlarged cross-sectional view showing an irradiation part and a patient of a heavy ion beam cancer treatment apparatus according to a fourth embodiment of the present invention.

FIG. 10 is a partially enlarged cross-sectional view showing an irradiated part and a patient of a heavy ion beam cancer treatment apparatus according to a fifth embodiment of the present invention.

FIG. 11 is a partially enlarged cross-sectional view showing an irradiated portion and a patient of a heavy ion beam cancer treatment apparatus according to a sixth embodiment of the present invention.

FIG. 12 is a partial perspective view showing a leaf in FIG. 11 in an enlarged manner.

FIG. 13 is a partially enlarged cross-sectional view showing an irradiated part and a patient of a heavy ion beam cancer treatment apparatus according to a seventh embodiment of the present invention.

FIG. 14 is a partially enlarged cross-sectional view showing an irradiated part and a patient of a heavy ion beam cancer treatment apparatus according to an eighth embodiment of the present invention. FIG. 15 is a schematic diagram showing an entire configuration of a conventional heavy ion beam cancer treatment apparatus. [16] FIG. 16 is a partially enlarged cross-sectional view showing an irradiation part and a patient of the heavy ion beam cancer treatment apparatus in FIG.

Explanation of symbols

1 Irradiation beam (radiation)

Three

4, A 'target

11, 21, 31, 41, 51, 61, 81 101 Heavy ion beam cancer therapy system (Heavy charged particle beam irradiation

12, 22, 32, 42, 52, 62, 82 102 Range compensator

13, 23, 25, 33, 35, 43, 45 53, 55, 63, 65, 67, 83, 85, 87, 89, 103

5 Leaf (energy absorber)

14 Energy absorption layer

15, 27, 28, 37, 38, 47, 48, 57, 58, 91, 92, 107, 108 Actuator 24, 34, 44, 54, 64, 84, 104 First energy absorption layer

26, 36, 46, 56, 66, 86, 106 Second energy absorbing layer

68, 88 Third energy absorption layer

90 Fourth energy absorption layer

Claims

The scope of the claims

[1] The radiation source is provided in the middle of the path of radiation irradiated from the radiation source toward the target, and

In a range compensator for absorbing energy and adjusting the range of radiation to the target,

A plurality of energy absorbers for absorbing the energy of the radiation;

An actuator for moving the body separately and independently toward the path of the radiation.

A range compensator characterized in that:

[2] The energy absorber is a leaf having an elongated plate-like physical strength.

The energy absorbing layer is constituted by arranging several rows in a row,

The range compensator as described.

[3] A plurality of the energy absorbing layers are arranged along the path of the radiation.

The range compensator according to claim 2.

[4] At least any one of the plurality of energy absorbing layers is a lead of one energy absorbing layer.

Moving the blade in a direction different from the leaves of the other energy absorbing layers.

Item 3. The range compensator according to item 3.

[5] At least any one of the plurality of energy absorbing layers is a lead of one energy absorbing layer.

Is formed with a thickness different from that of the leaves of the other energy absorption layers.

A range compensator according to claim 3 or claim 4.

[6] At least any one of the plurality of energy absorbing layers is a lead of one energy absorbing layer.

With a material that has a different energy absorption rate than the leaves of the other energy absorbing layers.

The range compensating device according to any one of claims 3 to 5, wherein the range compensating device is formed.

[7] At least any one of the plurality of energy absorbing layers is a lead of one energy absorbing layer.

Is formed with a plate width different from that of the leaves of the other energy absorption layers.

The range compensating device according to claim 1 or 2, wherein the range compensating device according to claim 6.

[8] In the energy absorbing layer, a pair of leaves are spaced apart from each other,

Claim 2 or Claim 7 characterized in that they are configured to be close to each other.

Range compensator.

[9] The leaf according to claim 2, wherein the leaf is formed with a tapered surface that is obliquely inclined.

9. The range compensator according to claim 1 or claim 1.

[10] The energy absorber is configured to advance and retreat during the irradiation of the radiation.

The range compensator according to claim 1, wherein the range compensator is the shift compensator according to claim 1.

[11] A feature is provided that the range compensating device according to any one of claims 1 to 10 is provided.

Heavy particle beam irradiation equipment.