JPH11285544A - Flying range modulator and charged particle ray theraputic instrument using the modulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the production of three-dimensionally flat dosage distribution, which has been difficult in a conventional charged particle ray irradiation device because the intensity of particles is modulated with the flying range demodulation of charged particles caused by the passage of the charged particles through a flying range modulator even if flatly adjusting the particle intensity of the charged particle in an optional irradiation field by a beam expander. SOLUTION: This flying modulator is provided with a flying range modulating body which the charged particle rays are inputted to and which adjusts the flying range of the charged particle rays and gives a prescribed scattering effect to the charging particle rays based on an inputting position where the charged particle rays were inputted, and provided with a scattering compensating body which the charged particle rays outputted from the flying range modulating body is inputted to and which uniformly adjusts the scattering effect given to the charged particle rays without regard to the inputting position to output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a range modulator for modulating the range of an incident charged particle beam, and a charged particle beam irradiation apparatus for irradiating an object to be irradiated with a charged particle beam using the range modulator. It is.

[0002]

2. Description of the Related Art An example of a charged particle beam irradiation apparatus is shown in FIG.
There is what was shown in. FIG. 4 is a configuration diagram showing a configuration of a conventional charged particle beam irradiation apparatus. In FIG. 4, reference numeral 1 denotes a charged particle beam. Reference numeral 2 denotes a beam expanding device, and the charged particle beam 1 is incident thereon. Reference numeral 3 denotes a range modulation device, and the charged particle beam 1 emitted from the beam expansion device 2
Is incident.

[0003] Reference numeral 4 denotes a range adjusting device.
The charged particle beam 1 emitted from the device is incident. Reference numeral 6 denotes a range compensating device, and the charged particle beam 1 emitted from the range adjusting device 4 enters through an irradiation field limiting device 5. Reference numeral 7 denotes a patient who is an irradiation target, and the charged particle beam 1 emitted from the range compensator 6 is incident thereon. Reference numeral 8 denotes an affected part, which is an irradiated part, to which the charged particle beam 1 incident on the patient 7 is irradiated.

Next, the operation of the conventional charged particle beam irradiation apparatus shown in FIG. 4 will be described. First, a charged particle beam 1, which is a charged particle beam, is emitted from an irradiation device. The charged particle beam 1 has a single energy. Then, the charged particle beam 1 is incident on the beam expanding device 2. Then, the charged particle beam 1 is enlarged and output. Next, the charged particle beam 1 output from the beam expanding device 2 is incident on a range modulation device 3. The range modulation device 3 adjusts and outputs the incident charged particle beam 1 so as to have an in-vivo range distribution in accordance with the thickness of the affected part 8. Note that the thickness of the affected part 8 is z in FIG.
Refers to a predetermined width in the axial direction.

[0005] The charged particle beam 1 output from the range modulator 3 is incident on a range adjuster 4. The range adjustment device 4 adjusts the distribution of the charged particle beam 1 in the body adjusted by the range adjustment device 3 so as to match the position of the entire affected part 8. An example of the range adjustment device 4 is a range shifter. The charged particle beam 1 output from the range adjustment device 3 is irradiated by the irradiation field limiting device 5.
The irradiation field is set. This irradiation field is the x of the affected part 8
-Y is set according to the two-dimensional projection shape,
An example of the irradiation field limiting device 5 is a collimator.

The charged particle beam 1 having passed through the irradiation field limiting device 5
Is incident on the range compensator 6. This range compensator 6
Adjusts the in-vivo range distribution of the charged particle beam 1 in accordance with the three-dimensional shape of the affected part 8 and suppresses irradiation to parts other than the affected part 8. A bolus is an example of the range compensator 6.
The charged particle beam 1 output through the range compensator 6
Irradiates the affected part 8 of the patient 7. In addition, affected part 8 of patient 7
The charged particle beam therapy for treating the diseased part 8 by irradiating the charged particle beam 1 to the body utilizes the property that charged particles decelerate in a substance. The charged particle beam irradiation device shapes and irradiates an irradiation beam according to the three-dimensional shape of the affected part 8.

Next, the configuration and operation of the beam expanding device 2 included in the conventional charged particle beam irradiation device shown in FIG. 5 will be described. The beam expanding device 2 shown in FIG.
Beam expansion device 2 using the Wobbler method shown in FIG.
5 and a beam expanding device 2 using the double scatterer method shown in FIG. 5B.

First, the configuration of the beam expanding device 2 shown in FIG. 5A will be described. Reference numeral 9 denotes an electromagnet pair including a pair of electromagnets. The beam expanding device 2 has two such pairs of electromagnets 9, and the charged particle beam 1 is sequentially incident between these two pairs of electromagnets 9. Note that these two electromagnet pairs 9 are arranged such that the directions of the magnetic fields are orthogonal to each other. When the charged particle beam 1 is incident on the circular deflection magnetic field formed by the two electromagnet pairs 9, the charged particle beam 1 rotates based on the circular deflection magnetic field.

Reference numeral 10 denotes a first scatterer, on which the charged particle beam 1 deflected by the electromagnet pair 9 is incident. The charged particle beam 1 incident on the first scatterer 10 is scattered so as to have a Gaussian distribution and forms an irradiation field having a flat particle intensity. In FIG. 5A, FIG.
The same or corresponding portions as those described above are denoted by the same reference numerals, description thereof will be omitted, and portions different from FIG. 4 will be described.

Next, the structure of the beam expanding device 2 shown in FIG. 5B will be described. Reference numeral 11 denotes a second scatterer. The second scatterer 11 is composed of two types of substances, a first substance and a second substance. These two types of substances are formed concentrically about the beam axis of the charged particle beam 1 incident on the first scatterer 10. The second scatterer 11
Of the two substances constituting the above, the first substance is provided inside the concentric second scatterer 11 and strongly scatters the incident charged particle beam 1 over a wide range. On the other hand, the second substance is provided outside the second scatterer 11, and does not scatter the incident charged particle beam 1 much as compared with the first substance.

In FIG. 5 (b), the same or corresponding parts as those in FIG. 5 (a) are denoted by the same reference numerals and the description thereof is omitted, and the parts different from FIG. 5 (a) are described. .
Next, the flow of the charged particle beam 1 in the beam expanding device 2 shown in FIG. 5B will be described. First, the charged particle beam 1 is incident on the first scatterer 10. When the charged particle beam 1 is scattered by the first scatterer 10, the scattered charged particle beam 1 is converted into a second scatterer 11.
Incident on. Then, the charged particle beam 1 incident on the first substance is scattered strongly and widely. On the other hand, the charged particle beam 1 incident on the second substance is output without being scattered much as compared with the first substance.

The reason why two substances having different degrees of scattering are provided in the second scatterer 11 is that even if the charged particle beam 1 is scattered by the first scatterer 10, the degree of scattering varies. That's why. Variations in the degree of scattering of the charged particles forming the charged particle beam 1 are caused by the first scatterer 1
The beam axis of the charged particle beam 1 incident on 0 is used as a reference. Many charged particles are scattered in the vicinity of an extension of this beam axis, that is, in the vicinity of the center of the second scatterer 11,
There is not much scattering at a position away from the beam axis, that is, near the second substance of the second scatterer 11. In other words, the particle strength of the charged particles is high near the extension of the beam axis, but low at positions far from the beam axis.

For this reason, the charged particle beam 1 is scattered by the first scatterer 10 and then further scattered by the second scatterer 1.
By being strongly scattered by the first material of the first scatterer while weakly scattered by the second material of the second scatterer 11,
An irradiation field where the particle strength of the charged particles becomes flat is formed.

Next, a beam expanding device 2 as shown in FIG.
The configuration and operation of the range modulation device 3 on which the charged particle beam 1 output from is input will be described with reference to FIG. The range modulator 3 shown in FIG. 6A is a range filter 3 of a ridge filter type, and the range modulator 3 shown in FIG. 6B is a rotating disk type. The range modulation device 3 shown in c) is a rotary cylinder type. First, in the ridge filter type range modulator of FIG. 6A, reference numeral 12 denotes a wedge-shaped ridge (hereinafter, referred to as a range modulator).
The range modulator 3 is obtained by arranging a plurality of range modulators 12. Based on the thickness of the range modulator 12,
The range of the charged particle beam 1 passing through the range modulator 12 is modulated.

Next, in the rotary disk type range modulation device 3 shown in FIG. 6B, reference numeral 13 denotes a rotation axis. The rotating disk type range modulator 3 is formed by arranging range modulators 12 having different thicknesses around a rotation axis 13. The rotating disk type range modulation device 3 rotates at high speed around the rotation axis 13 and receives the charged particle beam 1 from a direction parallel to the rotation axis 13 to temporally modulate the range. In FIG. 6B, the same or corresponding parts as those in FIG. 6A are denoted by the same reference numerals, and the description thereof will be omitted.
The part different from (a) has been described.

Further, in the rotary cylindrical range modulator 3 shown in FIG. 6C, the same or corresponding parts as those in FIG. 6B are denoted by the same reference numerals and description thereof is omitted. This rotary cylindrical range modulator 3 is parallel to the rotation axis 13,
The range modulators 12 having different thicknesses are arranged and formed so as to have a substantially cylindrical shape. This rotary cylindrical range modulator rotates at high speed around the rotation axis 13, and the charged particle beam 1 is incident from a direction perpendicular to the rotation axis 13 or from a twist position, and modulates the range over time. . The range of the charged particle beam 1 is modulated by these range modulators 12 to form a range distribution in the body based on the thickness of the affected part 8. FIG. 7 is a characteristic diagram showing characteristics of the range modulation device 3 that creates a constant high dose region with a length of about 14 cm in water under predetermined irradiation conditions.

[0017]

As described above, in the conventional charged particle beam irradiation apparatus, even if the particle intensity of the charged particles in an arbitrary irradiation field is adjusted to be flat by the beam expanding device 2, the charged particles do not fly. When the charged particles pass through the modulator 3, the range of the charged particles and the particle intensity are also modulated, making it difficult to form a three-dimensionally flat dose distribution. The present invention has been made in order to solve such a problem, and a range in which the range of charged particles is modulated without modulating the particle intensity of the charged particles adjusted flat by the beam expanding device 2. An object is to obtain a charged particle beam irradiation device including the modulation device 3.

[0018]

A range modulation apparatus according to the present invention receives a charged particle beam, adjusts the range of the charged particle beam, and controls the range of the charged particle beam based on the input position where the charged particle beam is input. A range modulator that imparts a predetermined scattering effect to the line, and a charged particle beam output from the range modulator are input,
And a scattering compensator that uniformly adjusts and outputs the scattering effect imparted to the charged particle beam regardless of the input position.

Further, the range modulation device according to the present invention comprises:
A charged particle beam is input, and a predetermined scattering effect based on the input position where the charged particle beam is input is set such that the scattering effect of the charged particle beam output from an arbitrary position of the range modulator is uniform. A scatter compensator to be applied to the beam and a charged particle beam output from the scatter compensator are input, and the range of the charged particle beam is adjusted, and the charged particle beam is determined based on the input position where the charged particle beam is input. And a range modulator that imparts a scattering effect.

Further, in the range modulation device according to the present invention, the charged particle beam is input, the range of the charged particle beam is adjusted based on the input timing of the input of the charged particle beam, and the predetermined range is applied to the charged particle beam. And a charged particle beam output from the range modulator, and uniformly adjusts and outputs the scattering effect imparted to the charged particle beam regardless of the input timing. A scattering compensator.

Further, the range modulation device according to the present invention comprises:
A charged particle beam is input, and a predetermined scattering effect based on the input timing at which the charged particle beam is input is set such that the scattering effect of the charged particle beam output at an arbitrary timing from the range modulator becomes uniform. The scattering compensator to be applied to the line and the charged particle beam output from the scattering compensator are input, and based on the input timing at which the charged particle beam is input, the range of the charged particle beam is adjusted and the charged particle beam is adjusted. And a range modulator for providing a predetermined scattering effect.

Further, in the range modulator according to the present invention, the range modulator in which the first scattering material is juxtaposed, and the relative position thereof is fixed near the range modulator, Using a second scattering substance having a higher scattering effect than the scattering substance, it is shaped into a shape based on the shape of the range modulator, and the scattering effect of the charged particle beam input from an arbitrary position via the range modulator is reduced. And a scattering compensator that adjusts the output as described above.

In the range modulator of the range modulator according to the present invention, the first scattering substance has a wedge shape.

Further, in the range modulation apparatus according to the present invention, a range modulation device in which first scattering materials having different thicknesses are formed side by side around the rotation axis and formed in a disk shape and rotated about the rotation axis. Body, provided in the vicinity of the range modulator, the range modulator and its relative positional relationship are fixed and rotated about the rotation axis, the second scattering material is higher than the first scattering material Scattering compensation that is shaped using the scattering substance of the shape of the range modulator, and uniformly adjusts the scattering effect of the charged particle beam input at an arbitrary input timing via the range modulator to output. It has a body.

The range modulator of the range modulator according to the present invention is formed by arranging first scattering materials having different thicknesses around the rotation axis and forming a disk-shaped or cylindrical shape. is there.

The charged particle beam therapy apparatus according to the present invention
A range modulator according to any one of claims 1 to 8.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 One embodiment of a range modulation device of a charged particle beam irradiation device according to the present invention will be described with reference to FIG. FIG. 1 is a sectional view showing a section of a range modulation device 3 according to the first embodiment. In FIG. 1, reference numeral 14 denotes a scattering compensator. This scattering compensator 14 allows the range modulator 1
The scattering effect generated in step 2 is compensated, and the particle intensity of the charged particles in the irradiation field is adjusted to be flat.

In other words, the scattering compensator 14 and the range modulator 12 pass through both the scattering compensator 14 and the range modulator 12 so that the scattering effect of the charged particles becomes constant at an arbitrary position. 12 are adjusted in association with each other. On the other hand, the thickness of the scattering compensator 14 is set so that the range of the charged particles does not change even when the range passes through the scattering compensator 14 and the range modulator 12 or only through the range modulator 12. Must be thin.

As described above, the scattering compensator 14 must compensate for the scattering effect of the charged particles by the range modulator 12 but must not affect the range modulation of the charged particles. It is desirable that the material be a highly scattering substance such as lead. Further, the range modulator 12 must modulate the range of the charged particles while suppressing the scattering effect of the charged particles as much as possible. Therefore, the range modulator 12 is desirably a low scattering material such as aluminum. In addition,
The low scattering substance is a substance having a small scattering effect / energy loss ratio, and specifically, a substance mainly containing a light element such as a plastic, beryllium, aluminum, graphite, or a light metal such as an organic compound. In addition, a high scattering substance has a property opposite to that of a low scattering substance,
It is a substance such as lead, uranium, and tungsten.

The range modulator 12 shown in FIG. 1 is wedge-shaped, and the beam axis of the charged particle beam 1 is orthogonal to the bottom surface of the wedge-shaped range modulator 12 facing the top. ing. However, there is no limitation on the shape and installation position of the range modulator 12. Further, the scattering compensator 14 of the present embodiment
Are formed corresponding to the arrangement of the wedge-shaped range modulators 12 arranged at intervals. In other words, in the scattering compensator 14 of the present embodiment, the portion where the charged particle beam 1 passing through the gap between the adjacent range modulators 12 is the thickest, and the top of the wedge-shaped range modulator 12 is formed. The thickness of the portion where the passing charged particle beam 1 is incident is the thinnest.

As described above, the shape of the scattering compensator 14 conforms to the shape of the range modulator 12. Conversely, if the shape of the range compensator 12 conforms to the shape of the range Is not asked. The range modulator 3 according to the present embodiment includes a range modulator 12.
And a scattering compensator 14. The range modulator 12 and the scattering compensator 14 are provided in the vicinity. this is,
This is because, if both are provided apart from each other, it becomes difficult to compensate for the scattering of one of them. In FIG. 1, the same or corresponding parts as those in the conventional example shown in FIG. 6 are denoted by the same reference numerals, and the description thereof will be omitted, and the parts different from FIG. 6 will be described.

Next, a method of designing the range modulator 12 and the scattering compensator 14 constituting the range modulator 3 will be described. First, let WL be the material thickness of the low scattering material that gives the same energy loss as 1 cm thick water to the low scattering material that is the material of the range modulator 12. Further, the same material thickness of the high scattering material which is the material of the scattering compensator 14 is denoted by WH. In addition, the material thickness of the low scattering material that gives the same scattering effect is XL, and the material thickness of the high scattering material is X
H. In the present embodiment, the charged particle beam 1
In the following description, a proton beam having a kinetic energy of 160 MeV is used, aluminum is used as a low scattering substance, and lead is used as a high scattering substance.

Then, according to the literature, the thickness of various materials is XL =
8.9cm, XH = 0.56cm, WL = 0.472c
m, WH = 0.174 cm. In addition,
This document refers to R.S. B. Review of Particle Properties by RMBarnett et al.
of Particle Properties) ”(Physical Review (Phy
sical Review) D 54 (1996) Part 1). According to this document, it is understood that the scattering effect is approximately inversely proportional to the square root of the thickness in the unit of the radiation length. For this reason, the radiation length itself was used as the thickness that gives the same scattering effect, and the various material thicknesses described above were calculated.

As a precondition, the range modulator 12
When the material thickness of (low scattering material) is zero, charged particle beam 1
Reaches the minimum range position. Further, the scattering compensator 14
When the material thickness of (highly scattering material) is zero, charged particle beam 1
Reaches the maximum range position. When the thickness of the range modulator 12 or the scattering compensator 14 cannot be reduced to zero due to the mechanical structure, in this case, the thickness obtained by subtracting the minimum thickness from the thickness of the range modulator 12 or the scattering compensator 14 is obtained. The following calculation formula is derived based on the thickness of. And this minimum thickness is
It is treated completely differently as a coherent offset of range modulation, i.e. just a range movement.

The distance between the minimum range position and the maximum range position is defined as the range modulation width Sobp. The amount of movement of the charged particles in the direction of the maximum range position based on the minimum range position is referred to as a relative range movement amount R. The relative range movement amount R changes depending on the incident position where the charged particle beam 1 is incident on the range modulator 12. Note that these range modulators 12 and / or
Alternatively, the scattering effect of the charged particle beam 1 passing through the scattering compensator 14 is adjusted to be constant.

When an equation is constructed in consideration of the above constants and preconditions, the material thickness TL of the low scattering substance can be obtained by the following equation. TL = XL * R / (XL / WL−XH / WH) Further, the material thickness T of the high scattering material based on the relative range movement amount R
H is as follows. TH = XH * (Sobp-R) / (XL / WL-XH / W
H)

For example, when the range modulation width Sobp = 10 cm, when the charged particle beam 1 reaches the minimum range position (relative range movement amount R = 0 cm), the maximum thickness TH of the lead which is the scattering compensator 14 is TH. Is 0.36 cm. Further, when the charged particle beam 1 reaches the maximum range position (relative range movement amount R = range modulation width Sobp = 10 cm), the maximum thickness TL of the aluminum which is the range modulator 12 is 5.7 cm. . Note that an offset of the range modulation, in this example, a range movement of 0.36 cm of lead (2.1 cm in water) occurs, but this offset is compensated by changing the beam energy, setting the range adjustment device 4 and the like. it can.

As described above, since the scattering effect of the charged particle beam irradiation apparatus of the present embodiment is also added from the range modulation device 3, the charged particle beam irradiation apparatus of the present embodiment is different from the conventional charged particle beam irradiation apparatus. Unlike the apparatus, the setting is made in consideration of the beam expanding apparatus 2 and the range modulation apparatus 3 comprehensively. Note that the charged particle beam irradiation apparatus according to the present embodiment includes a charged particle beam 1
Is applied to the affected part 8 to treat the affected part 8.

As described above, the range modulation device 3 of the present embodiment
Can scatter the incident charged particle beam 1 in the same manner, and make the particle intensity of the charged particle in the predetermined irradiation area flat and uniform, so that the irradiation of the charged particle beam 1 in the predetermined irradiation area Unevenness can be suppressed. In addition, if the range modulation device 3 of this embodiment is used for a charged particle therapy device, a predetermined diseased part 8 can be treated with a uniform dose according to a treatment plan, and the treatment effect can be improved.

Further, the range modulation device 3 of this embodiment is
The size can be reduced more than the range modulation device 3 shown in other embodiments. This is because the range modulator 3 according to the other embodiment is driven to rotate. The range modulator 3 according to the present embodiment includes a space that must be ensured for rotational drive and the range modulator 3. This is because there is no need to provide a mechanism for rotating the.

Embodiment 2 FIG. 2 shows another embodiment of the range modulation device 3 according to the present invention. FIG. 2 is a cross-sectional view illustrating a cross section of the range modulation device 3 according to the second embodiment. Note that FIG.
In FIG. 1, the same or corresponding parts as those in the first embodiment shown in FIG. The range modulator 12 of the present embodiment is the same as the range modulator 12 of the conventional rotating disk type range modulator 3.

The scattering compensator 14 is provided on the same rotation axis 13 as the range modulator 12. This scattering compensator 14
Rotates at the same timing as the range modulator 12, and its shape and thickness are formed corresponding to the shape and thickness of the range modulator 12. That is, the correspondence between the range modulator 12 and the scattering compensator 14 is maintained even during rotation. Further, the range modulator 12 and the scattering compensator 14 may be integrally formed.

As described above, the range modulation device 3 of the present embodiment
Can scatter the incident charged particle beam 1 in the same manner, and make the particle intensity of the charged particle in the predetermined irradiation area flat and uniform, so that the irradiation of the charged particle beam 1 in the predetermined irradiation area Unevenness can be suppressed. In addition, if the range modulation device 3 of this embodiment is used for a charged particle therapy device, a predetermined diseased part 8 can be treated with a uniform dose according to a treatment plan, and the treatment effect can be improved.

Embodiment 3 FIG. FIG. 3 shows another embodiment of the range modulation device 3 according to the present invention. FIG. 3 is a cross-sectional view illustrating a cross section of the range modulation device 3 according to the third embodiment. Note that FIG.
In FIG. 1, the same or corresponding parts as those in the first embodiment shown in FIG. Note that the scattering compensator 14 of the present embodiment is formed integrally with the range modulator 12 and is formed in a substantially cylindrical shape.

The scattering compensator 14 rotates at the same timing as the flight modulator 12, and its shape and thickness are
It is formed corresponding to the shape and thickness of the flight modulator 12. That is, the correspondence between the range modulator 12 and the scattering compensator 14 is maintained even during rotation. The charged particle beam 1 is also incident on the range modulation device of the present embodiment from a direction perpendicular to the substantially cylindrical rotating shaft 13 or from a twisted position, similarly to the related art. Although the substantially cylindrical range modulator 3 of the present embodiment has a smooth outer periphery, it may have a smooth inner periphery.

In the substantially cylindrical range modulator 3 of the present embodiment, the scattering compensator 14 is provided on the outer peripheral side, and the range modulator 12 is provided on the inner peripheral side. May be provided with a scattering compensator 14, and the range modulator 12 may be provided on the outer peripheral side. Further, the substantially cylindrical range modulator 3 of the present embodiment.
Although the scattering compensator 14 and the range modulator 12 are integrally formed, they may be formed in a substantially cylindrical shape, and may be synchronously rotated at the same rotation axis 13 and at the same timing.

That is, the range modulator 12 and the scattering compensator 14
Is maintained even during rotation, and the shape and thickness of the range modulator 12 and the scattering compensator 14 are formed corresponding to each other. In addition, in these two substantially cylindrical shapes, the range modulator 12 may be provided on the rotating shaft 13 side,
The scattering compensator 14 may be provided on the rotating shaft 13 side.

As described above, the range modulation device 3 of the present embodiment
Can scatter the incident charged particle beam 1 in the same manner, and make the particle intensity of the charged particle in the predetermined irradiation area flat and uniform, so that the irradiation of the charged particle beam 1 in the predetermined irradiation area Unevenness can be suppressed. In addition, if the range modulation device 3 of this embodiment is used for a charged particle therapy device, a predetermined diseased part 8 can be treated with a uniform dose according to a treatment plan, and the treatment effect can be improved.

[0049]

According to the range modulation apparatus of the present invention, a charged particle beam is input, the range of the charged particle beam is adjusted, and a predetermined value is applied to the charged particle beam based on the input position where the charged particle beam is input. A range modulator that provides a scattering effect and a charged particle beam output from the range modulator are input, and the scattering effect applied to the charged particle beam is adjusted uniformly regardless of the input position and output. And a compensator, which scatters all the incident charged particle beams in the same manner, and makes it possible to make the particle intensity of the charged particles in the predetermined irradiation region flat and uniform. Irradiation unevenness of the charged particle beam can be suppressed.

The charged particle beam therapy apparatus according to the present invention
It has the range modulation device according to any one of claims 1 to 8, and scatters all the charged particle beams incident thereon in the same manner, so that the particle intensity of the charged particles in a predetermined irradiation area is evenly and evenly. Therefore, a predetermined affected part can be treated with a uniform dose according to a treatment plan, and the treatment effect can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a cross section of a range modulation device 3 included in a charged particle beam irradiation apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a cross section of a range modulation device 3 included in a charged particle beam irradiation apparatus according to a second embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating a cross section of a range modulation device 3 included in a charged particle beam irradiation apparatus according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram showing a configuration of a conventional charged particle beam irradiation apparatus.

5A and 5B are configuration diagrams showing a configuration of a beam expanding device 2 included in a conventional charged particle beam irradiation device. FIG. 5A is a beam expanding device 2 using a Wobbler method, and FIG. 5B is a double scatterer. This is a beam expansion device 2 using a method.

6A and 6B are configuration diagrams showing a configuration of a range modulation device 3 included in a conventional charged particle beam irradiation apparatus, wherein FIG. 6A is a range modulation device 3 of a ridge filter type, and FIG. (C) is a rotary cylindrical range modulator.

FIG. 7 is a characteristic diagram showing characteristics of the range modulation device 3 under predetermined irradiation conditions.

[Explanation of symbols]

1 charged particle beam, 2 beam expansion device, 3 range modulation device, 4 range adjustment device, 5 irradiation field limiting device, 6
Range compensator, 7 patients, 8 affected area, 9 electromagnet pairs, 1
0 first scatterer, 11 second scatterer, 12 range modulator, 13 rotation axis, 14 scattering compensator.

Claims (9)

[Claims] 1. A range in which a charged particle beam is inputted, a range of the charged particle beam is adjusted, and a predetermined scattering effect is imparted to the charged particle beam based on an input position where the charged particle beam is inputted. A modulator and a scattering compensator to which the charged particle beam output from the range modulator is input, and that the scattering effect imparted to the charged particle beam is uniformly adjusted and output regardless of the input position. A range modulation device, comprising: 2. A method according to claim 1, wherein the charged particle beam is inputted and a predetermined value based on the input position where the charged particle beam is inputted so that the scattering effect of the charged particle beam outputted from an arbitrary position of the range modulator is uniform. A scattering compensator that imparts the scattering effect of the charged particle beam to the charged particle beam, the charged particle beam output from the scattering compensator is input, and the range of the charged particle beam is adjusted, and the charged particle beam is input. A range modulator that imparts a predetermined scattering effect to the charged particle beam based on the input position obtained. 3. A charged particle beam is inputted, a range of the charged particle beam is adjusted based on an input timing of the input of the charged particle beam, and a flying distance for giving a predetermined scattering effect to the charged particle beam is provided. And a scattering compensator to which the charged particle beam output from the range modulator is input, and that the scattering effect imparted to the charged particle beam is uniformly adjusted and output regardless of the input timing. A range modulation device comprising: 4. A predetermined method based on the input timing at which the charged particle beam is input so that the scattering effect of the charged particle beam output at an arbitrary timing from the range modulator is uniform. A scattering compensator that imparts the scattering effect of the charged particle beam to the charged particle beam, and the charged particle beam output from the scattering compensator is input, based on the input timing at which the charged particle beam is input, A range modulator that adjusts a range and imparts a predetermined scattering effect to the charged particle beam. 5. A range modulator in which a first scattering substance is juxtaposed, and a relative position is fixed near the range modulator,
Formed into a shape based on the shape of the range modulator using a second scattering material having a higher scattering effect than the first scattering material, and charged particles input from an arbitrary position via the range modulator A range compensator comprising: a scattering compensator for uniformly adjusting and outputting a line scattering effect. 6. The range modulator according to claim 5, wherein the range modulator has a wedge-shaped first scattering material. 7. A range modulator in which first scattering substances having different thicknesses are arranged side by side around a rotation axis and are formed in a disk shape, and the range modulator rotates about the rotation axis. Provided in the vicinity, the range modulator and its relative positional relationship are fixed and rotated about the rotation axis, using a second scattering material having a higher scattering effect than the first scattering material. And a scattering compensator that is formed into a shape based on the shape of the range modulator and uniformly adjusts and outputs the scattering effect of the charged particle beam input at an arbitrary input timing via the range modulator. A range modulation device, comprising: 8. The range modulator according to claim 7, wherein first scattering substances having different thicknesses are arranged side by side around the rotation axis, and are formed in a disk shape or a cylindrical shape. Range modulation device. 9. A charged particle beam therapy device comprising the range modulation device according to claim 1. Description: