JP2003190304A - Particle beam therapy system - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To improve the operation rate of a particle beam treatment more accurately and simplified. SOLUTION: A cutout portion 2a is arranged in a part of a top 2 of a treatment table on which a patient is placed, and when irradiating a beam from below, a particle beam is directly irradiated to a human body without passing through the top 2. It was to so.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a treatment table of a particle beam therapy system for irradiating a cancer patient with a beam of charged particles for treatment.

[0002]

2. Description of the Related Art FIG. 8 shows, for example, "Mitsubishi Electric Technical Report Vol.
69 No. 2 1995 p45-49 HIMAC
FIG. 4 is a conceptual view showing a conventional treatment apparatus of this kind shown in FIG. 3 of “Heavy particle beam irradiation positioning apparatus for use”, (a) is a perspective view of the apparatus, and (b) and (c) are its treatment states. It is a front view. In the figure, 1 is a treatment table, 2 is its top plate, 3 is a column of the treatment table, and 4 is a drive which is mounted between the column 3 and the top plate 2 to move the top plate 2 in parallel and rotationally. It is a mechanism. An irradiation nozzle 5 is arranged below the treatment table 1 and emits a charged particle beam. In addition, the same figure (b) (c) shows the conceptual diagram seen from the direction of the head of the patient placed on the treatment table, 11 is the patient placed on the top 2 on the back, and 12 is the patient. It is a beam of charged particles emerging from the irradiation nozzle 5 below. Further, FIG. 6C shows a conceptual diagram at the time of positioning, 13 is an X-ray tube that emits X-rays 14,
15 detects X-rays that have passed through the patient 11 and the top plate 2,
It is a detector for displaying as an image, and is composed of a II tube (image intensifier), an imaging plate, and the like.

Next, the operation will be described. A particle beam such as a proton beam or a heavy particle beam, which is used particularly for cancer treatment, imparts energy with a characteristic peak called a Bragg curve in a substance, and kills tumor cells. The peak depends on the energy of the particle beam and the type and thickness of the substance. Particle beam therapy can reduce the dose delivery to normal tissue far more than conventional radiation treatment with this specific dose distribution, but in order to eliminate the extra dose delivery to normal tissue, the optimal angle for the human body Irradiation is performed. In particular, with a rotatable irradiation nozzle called a rotating gantry, an arbitrary angle is selected, and irradiation is also performed from below through the treatment table. Moreover, not only the distribution of particle beams in the depth direction but also the distribution in the lateral direction is more concentrated than the conventional distribution of X-rays, etc. by using a collimator etc. to block the excess part. There is a need for more accurate patient alignment. For this positioning,
As shown in (c) of the figure, the patient on the treatment table is irradiated with X-rays from the vertically upper direction, and the X-rays transmitted thereunder are received by a detector such as an image intensifier or an imaging plate. The position of the bone in the body is detected from the image, the amount of deviation from the target position is determined, and the treatment table is moved to perform positioning. At this time, the irradiation nozzle is in the retracted position (rotated) so as not to interfere with the X-ray detector in the case of a rotating gantry, or the X-ray tube is in another place in the case of a fixed nozzle. , The treatment table is switched only by parallel movement or rotation movement. In the above description of positioning, only one direction (referred to as front direction) has been described, but in some cases, a combination of X-rays from the side surface and a detector may be used.

By the way, as shown in FIG. 8, for example, an important organ is located on the upper surface side of the affected part of a patient lying on his back, and radiation is absorbed only in the affected part without irradiating the important organ with radiation as much as possible. In order to do so, there is no choice but to irradiate from below. In this case, the beam emitted from the irradiation nozzle must also pass through the top plate of the treatment table, so the energy of the beam to be irradiated is increased by the accelerator for that amount, considering the material and thickness of that portion. To be done. Therefore, the top plate is made of a material that is as thin and rigid as possible so that those energies are not wasted.

[0005]

In the conventional particle beam therapy system, when the beam is irradiated from below, the beam passes through the top plate and irradiates the affected area. Therefore, the energy of the particle beam is correspondingly increased. It is impaired and reaches a shallow depth within the patient's body. Therefore, there is a problem in that there may be cases where treatment cannot be performed on a patient whose position of the affected part is deep as viewed from the beam direction. Even if it can be reached sufficiently, when irradiation is performed obliquely from below by a rotating gantry, etc., there will be a part that passes through the top plate of the treatment table and a part that does not, and simply consider only the thickness of the top plate. Instead, it is necessary to specify the position of the top plate boundary with respect to the affected part and set the parameters of the irradiation system, which complicates the treatment plan. Furthermore, even in the case of positioning by X-rays, the image of the X-rays transmitted through the human body and the top plate is seen, so there is absorption and scattering of the X-rays at the top plate portion, and the image quality deteriorates accordingly. There is a question to do.

The present invention has been made in order to solve the above-mentioned problems, and increases the number of patients to be treated and treats the treatment from obliquely below so that the beam partially passes through the top plate. It is a simplified treatment plan. Even if the irradiation is not from below, the image can be made clearer when positioning the patient, so that the positioning can be speeded up, and more accurate treatment and an increase in operating rate can be achieved. .

[0007]

A particle beam therapy system according to claim 1 of the present invention is for irradiating an affected part of a patient with a charged particle beam such as a proton beam or a heavy particle beam for treatment. A notched part is provided in a part of the top plate of the treatment table on which the particle beam is irradiated from below, and the particle beam is directly irradiated to the human body without passing through the top plate. It was done.

In the particle beam therapy system according to the second aspect of the present invention, the notched portion is preliminarily detachable and detachable.

In the particle beam therapy system according to the third aspect of the present invention, the means for irradiating the beam from below is a rotating gantry.

In the particle beam therapy system according to claim 4 of the present invention, the cutout portion is prepared by preparing a top plate arranged at various positions on the top plate and exchanging the top plate for cutting. The missing part is adapted to the irradiated part to be irradiated.

A particle beam therapy system according to a fifth aspect of the present invention is such that a beam shaping device such as a filter or a collimator is attached to a notched portion of the top plate.

A particle beam therapy system according to a sixth aspect of the present invention comprises a support rod projecting in the longitudinal direction of the top plate, and a block divided into the support rods is fitted into the top plate to form the top plate. At the same time, the notch is formed.

In the particle beam therapy system according to the seventh aspect of the present invention, a spacer is interposed between the blocks so that the place where the hole-shaped notch is formed can be arranged at an arbitrary position depending on the order of the block and the spacer. It is a thing.

The particle beam therapy system according to the eighth aspect of the present invention uses a block having hole cutouts so that the hole cutouts can be arranged at free positions depending on the order of the blocks. .

In the particle beam therapy system according to claim 9 of the present invention, a block with a collimator or a filter is used as a block having a hole-shaped notch, and it can be arranged at any position. is there.

According to a tenth aspect of the particle beam therapy system of the present invention, the lower surface of the block is previously recessed so that the depth at which the particle beam reaches matches the shape of the affected part. The notch portion is formed.

In the particle beam therapy system according to claim 11 of the present invention, all the divided blocks are made of the same material.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a particle beam therapy system according to Embodiment 1 of the present invention.
Is a perspective view, and (b) and (c) are cross-sectional views of a cutout portion showing a treatment state, respectively. In FIG. 1, 1 is a treatment table, 2 is its top plate, and this top plate 2 is made of a material such as CFRP. Reference numeral 2a denotes a portion (indicated by a hole in the drawing) obtained by cutting out a part of the top plate 2. Reference numeral 3 is a support of the treatment table, and 4 is a drive mechanism attached to the support 3 for moving the top 2 up and down, left and right, and rotating. An irradiation nozzle 5 is arranged below the top plate 2, and a particle beam is emitted from the irradiation nozzle 5 to treat the patient 11 on the treatment table.
The irradiation nozzle 5 may be fixed to the floor or may be a rotating gantry irradiation nozzle. FIG. 1B is a view showing the principle, and shows a case where a cross section with a notch is seen from the longitudinal direction of the treatment table. Reference numeral 11 denotes a patient to be treated, which has an affected area A to be irradiated inside the body. 12
Represents a particle beam emitted from the irradiation nozzle 5. Further, FIG. 7C shows a cross section in positioning, 13 is an X-ray tube for emitting X-rays, and 1 is an X-ray tube.
Reference numeral 5 denotes a detector for detecting X-rays that have passed through the patient 11 and the top plate 2 and displaying them as an image, and includes a II tube (image intensifier), an imaging plate, and the like.

Next, the operation will be described. In the particle beam therapy system according to the first embodiment described above, a hole-shaped notch 2a is formed in the vicinity of the center of the top plate 2, and when the patient 11 is placed on the top plate 2, FIG. ), The affected area A is placed directly above the hole-shaped cutout 2a. Therefore, the irradiation nozzle 5 has the notch 2
The beam 12 irradiates the human body through the a without passing through the top plate material. Also, when aligning the figure (c), the X-ray 14 can only pass through the notch 2a between the X-ray tube 13 and the X-ray detector 15 and only the human body or thin clothing such as underwear worn. I'm trying to pass.

As described above, according to the first embodiment,
The treatment beam can irradiate the affected area from below without passing through the top plate material, and since there is no energy loss or scattering of the beam in the top plate material, the affected part A such as a tumor is located at a deep position from the beam. Also, irradiation treatment becomes possible. In addition, when the patient's top plate is moved and aligned, only the human body passes through the part including the tumor in the X-ray transmission area between the X-ray tube and its detector. Since the projection image of the skeleton around the tumor becomes clearer, the time required for the alignment is reduced, and an excellent effect is achieved in achieving more accurate alignment.

The notch may be provided with a slit in the top plate in advance so that only the part can be removed at the time of use to form the notch.

Embodiment 2. FIG. 2 is a configuration diagram showing a treatment table of a particle beam therapy system according to Embodiment 2 of the present invention. In the figure, the positions of the notches of the top plate 2 are 2a, 2b, and 2c. Three types (2A, 2B, 2C in the figure) are prepared. Among them, suitable ones can be replaced according to the treatment site of the patient, and can be detachably attached to the drive mechanism 4 of the treatment table as appropriate. .

In the treatment table of the particle beam therapy system according to the second embodiment, various cutout tops are prepared, and by replacing the top in advance according to the treatment site of the patient, the position of the patient can be changed. Since it is not necessary to move the to fit the notch on the top plate, the burden on the patient can be reduced. That is, according to the second embodiment, in addition to the same merits as those of the first embodiment, there is no need to move the patient. For example, in the case of the top plate having the cutout portion 2b, particularly when it is possible to irradiate by changing the angle freely like a rotating gantry, and when it is obliquely from below,
A part of the beam does not pass through the top plate by the time it reaches the tumor, which simplifies treatment planning.

Embodiment 3. FIG. 3A is a configuration diagram showing a treatment table of a particle beam therapy system according to a third embodiment of the present invention. In the figure, 6 is a collimator made of a material such as brass, and a hole 6a is formed in the shape of the irradiation field (the area to be irradiated along the affected part of the patient) for each patient. Also, 7
Indicates various devices for shaping the beam, called compensation filters and ridge filters. In the conventional irradiation device, the collimator 6 and the filter 7 are incorporated in the irradiation nozzle 5.

In the treatment table of the particle beam therapy system according to the third embodiment, the cutout portion 2a of the top plate 2 shown in FIG. 3B is used.
The collimator 6 is attached to the collimator 6, and various filters 7 such as a compensating filter and a ridge filter are attached to the collimator 6 in an overlapping manner. Therefore, normally, the irradiation nozzle 5
The collimator and various filters installed on the side can be installed closer to the affected area of the patient.

As described above, according to the third embodiment, in addition to the merit that the beam can not be passed through the top plate 2 and the irradiation can be performed from below, the collimator and various filters are located closer to the affected area of the patient. If it is installed and the position of the patient is accurately aligned with this collimator, there is no problem because the beam that hits the affected area is determined by the collimator even if the positions of the nozzle and the treatment table are slightly deviated. Further, since the collimator is closer to the affected area, the effect such as the beam penumbra is reduced, and the contrast of the beam is sharpened.

Fourth Embodiment 4A and 4B are configuration diagrams showing a treatment table of a particle beam therapy system according to Embodiment 4 of the present invention, where FIG. 4A is a perspective view and FIG. 4B is a plan view. In the figure,
1 is a treatment table, 2 is a part of the top plate 2, and 8 is this top plate 2.
It is a support rod that sticks out on both sides of the to maintain rigidity.
9 and 16 are blocks made of a material such as CFRP,
The penetrating portions 9 are provided so that they can pass through the supporting rods 8.
a and 16a are provided. This block has a spacer type 16 that allows only one support rod to pass through and a block 9 that allows both support rods to pass through. Prepare blocks with various thicknesses in the direction to skewer the support rods. There is. Then, the spacer block 16 plays a role of a spacer that adjusts the interval between the blocks 9, and by skewering these into the support rod 8 as shown in FIG.
The top plate is integrally formed to form the cutout portion 2a.
To form.

In the treatment table of the particle beam therapy system according to the fourth embodiment, the top plate is in the form of a divided block, and these can be inserted into the support rod 8 in any order.
By combining blocks or spacer blocks having various thicknesses and changing the order thereof, it becomes possible to arrange a portion having a hole having an arbitrary width at an arbitrary position. Therefore, by combining the position of this hole with the affected part of the patient so that it comes to the part to be irradiated by the patient, in the irradiation treatment from below, without passing through the top plate from the irradiation nozzle, the treatment beam is irradiated, It is possible to obtain a transmission image for positioning with X-rays. With the above-described configuration, it is possible to deal with the combination of the blocks only, without preparing any kind of notched top plate as shown in the second embodiment.

In the above description, the cutout portion 2a is manufactured by using the pair of spacer blocks 16, but the block 9 having the hole-shaped cutout portion is prepared. The perforated block may be used instead of the spacer block 16.

Embodiment 5. 5A and 5B are configuration diagrams showing a treatment table of a particle beam therapy system according to Embodiment 5 of the present invention. FIG. 5A is a perspective view and FIG. 5B is an assembly plan view. In the figure, reference numerals 2, 3, 4, and 8 are the same as those shown in the fourth embodiment, and therefore their explanations are omitted. Reference numeral 10 is a block in which a collimator made of a material such as brass is formed. The block 10 has a penetrating portion 10a so that the supporting rod 8 can be passed therethrough, and a hole-shaped notch portion 10b is provided.
Further, 9 is a block made of a material such as CFRP, which has various thicknesses in the direction in which the support rod 8 is skewered. And these blocks 9, 1
By skewering 0 into the support rod 8, the whole top plate is integrally formed.

In the treatment table of the particle beam therapy system according to the fifth embodiment, the top plate is in the form of a divided block and can be put in any order together with the block of the collimator which forms the irradiation field of the patient. It is possible to arrange the collimator block at an arbitrary position by changing the combination of blocks having various thicknesses and the order of the blocks of the collimator. Therefore, by combining the position of the collimator block 10 with the affected part of the patient so that the notch 10b matches the part of the patient to be irradiated, the irradiation nozzle from below does not pass through the top plate from the irradiation nozzle. It is possible to irradiate the treatment beam, and it is possible to collimate the beam at a position near the affected part of the patient instead of the irradiation nozzle, and it is possible to reduce the influence of penumbra blurring and the like.

Sixth Embodiment 6 is a perspective view showing the configuration of a treatment table of a particle beam therapy system according to a sixth embodiment of the present invention. In the figure, reference numerals 2, 3, and 4 denote the fifth embodiment.
The reference numeral 17 denotes a top plate frame which is formed in such a manner as to project in a U-shape from a portion corresponding to a part of the top plate 2 to one side and serves as a structure for ensuring the rigidity of the treatment table. 9 is CFR
It is a block made of a material such as P and has a groove 9 on its lower surface.
b is provided so that the groove 9b of the block 9 can be engaged with the frame 17 and arranged. Next, 10 is a block in which a collimator made of a material such as brass is formed, and like the block 9, a groove 10c is provided on the lower surface thereof, and this groove 10c can be inserted and arranged in the frame 17. You can do it. Then, these blocks 9 and 10 are connected to the frame 17
The whole top plate is integrally formed by interlocking and inserting. In addition, 10b is a hole-shaped notch formed in the block 10.

In the treatment table of the particle beam therapy system according to the sixth embodiment, the top plate is in the form of a divided block, and the grooves 9b and 10c provided in the lower part of the top plate make the top surface of the treatment table top plate frame 17 upper surface. It can be installed from. In this case, since the block 10 of the collimator that forms the irradiation field of the patient is also configured in the same manner, the collimator block 10 can be removed from the upper surface of the treatment table when being inserted in any order,
Easy to change the order. That is, it is possible to arrange the collimator block at an arbitrary position by changing the combination of the blocks 9 and 10 having various thicknesses and the order thereof. Therefore, in the present embodiment, it is possible to obtain the same effect as that of the fifth embodiment, and it is possible to easily change the arrangement, that is, the rearrangement of the blocks.

Embodiment 7. FIG. 7 is a perspective view showing the structure of a treatment table of a particle beam therapy system according to a seventh embodiment of the present invention.
FIG. 9A is a sectional view of the compensating filter 18 and FIG. 17A, in which 17 is a top plate frame which is a structure having rigidity of the treatment table, and 9 is made of a material such as polyethylene as in the sixth embodiment. It is a block, and a groove 9b is provided on the lower surface thereof so that the groove 9b can be arranged so as to be engaged with the top plate frame 17. on the other hand,
Reference numeral 18 is a compensating filter in which the polyethylene block 9 is three-dimensionally processed, and has a groove 18a on the lower surface thereof so that it can be arranged so as to be engaged with the top plate frame 17. And these blocks 9, 1
By engaging 8 with the top frame 17, the top is integrally formed. The compensating filter 18 is made of water-equivalent material such as polyethylene, and has a recessed notch 18b previously drilled with a drill or the like in order to match the depth of the affected area with the beam arrival point. The concave notch is processed so that the thickness of the compensation filter 18 and the thickness up to the end of the affected part of the human body are constant when viewed from the beam.
In the conventional device, this is attached to the tip of the irradiation nozzle.

In the treatment table of the particle beam therapy system according to the seventh embodiment, the top plate is in the form of a divided block, and the groove is provided in the lower part of the top plate so that the top plate can be attached to the treatment table top frame. Since the block is made of the same material as the compensating filter 18, the compensating filter can be manufactured by excavating any block. This makes it possible to create a treatment table and compensation filter without increasing the types of materials,
Moreover, it is possible to set the compensation filter so as to come to the position of the affected area. In particular, it is possible to reuse the compensation filters drilled and used for other patients in blocks other than the block of compensation filters through which the beam passes. In this way, the material can be reused and the type of block can be unified into one type of the same material as the compensating filter, which facilitates cost reduction.

[0036]

According to the invention as set forth in claim 1, since the treatment beam irradiates the affected area from below without passing through the top plate material, there is no energy loss or scattering of the beam in the top plate material. Irradiation treatment is possible even if the affected area A such as a tumor is located deep from the beam. In addition, when the patient's top plate is moved and aligned, only the human body passes through the part including the tumor in the X-ray transmission area between the X-ray tube and its detector. Since the projection image of the skeleton around the tumor becomes clearer, the time required for the alignment is reduced, and an excellent effect is achieved in achieving more accurate alignment.

According to the invention as set forth in claim 2, in addition to the effect as set forth in claim 1, since it is constructed so as to be detachable so that only the cutout portion can be removed at the time of use, it is extremely convenient in handling.

According to the invention described in claim 3, in addition to the effect described in claim 1, by using the rotating gantry,
Irradiation can be performed by freely changing the angle, and the beam can easily reach the affected area from diagonally below.

According to the invention as set forth in claim 4, in addition to the effect as set forth in claim 1, by preparing a top plate having a plurality of types of cutout portions, the cutout portion is irradiated to the affected area. It is possible to match exactly on an ad-hoc basis.

According to the invention described in claim 5, in addition to the effect described in claim 1, the beam shaping device can be attached to a portion closer to the affected area of the patient.

According to the invention described in claim 6, it is not necessary to prepare several kinds of top plates having cutout portions at different places, which is more efficient.

According to the seventh and eighth aspects of the present invention, it becomes possible to dispose the hole-shaped notch at a free position.

According to the invention as defined in claim 9, it is possible to freely dispose a block having a collimator or a filter in the cutout portion.

According to the tenth aspect of the invention, since the recessed notch is formed on the lower surface of the block, it can be easily adapted to the affected area of the patient.

According to the eleventh aspect of the invention, since the divided blocks are made of the same material, they can be reused.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a particle beam therapy system according to a first embodiment of the present invention, in which (a) is a perspective view and (b) and (c) are sectional views showing a treatment state.

FIG. 2 is a perspective view showing a conceptual view of a treatment table of a particle beam therapy system according to Embodiment 2 of the present invention.

FIG. 3 is a perspective view showing a conceptual diagram showing a particle beam therapy system according to a third embodiment of the present invention.

FIG. 4 is a perspective view (a) and a plan view (b) showing a conceptual view of a treatment table of a particle beam therapy system according to Embodiment 4 of the present invention.

FIG. 5 is a perspective view (a) and a plan view (b) showing a conceptual view of a treatment table of a particle beam therapy system according to a fifth embodiment of the present invention.

FIG. 6 is a perspective view showing a conceptual view of a treatment table of a particle beam therapy system according to Embodiment 6 of the present invention.

FIG. 7 is a perspective view (a) showing a conceptual view of a treatment table of a particle beam therapy system according to a fourth embodiment of the present invention and a sectional view (b) of a block.

8A and 8B are conceptual views of a conventional particle beam therapy system, in which FIG. 8A is a perspective view, and FIGS. 8B and 8C are side views showing a therapeutic state thereof.

[Explanation of symbols]

1 treatment table, 2 top plate, 2a notch, 3 support,
4 drive mechanism, 5 irradiation nozzle, 6 collimator, 7
Filter, 8 support rods, 9, 10 blocks, 11
Patient, 12 particle beam, 16 spacer block,
17 frames, 18 compensation filter, A affected area.

Claims (11)

[Claims] 1. A radiotherapy apparatus for irradiating an affected part of a patient with a charged particle beam such as a proton beam or a heavy particle beam for treatment.
A notched part is placed in a part of the top plate of the treatment table on which the patient is placed, and when the beam is irradiated from below, the particle beam is directly irradiated to the human body without passing through the top plate. A particle beam therapy system characterized by being constructed. 2. The particle beam therapy system according to claim 1, wherein the cutout portion is preliminarily detachable and detachable. 3. The rotating gantry as claimed in claim 1, wherein the means for irradiating the beam from below is a rotating gantry.
The described particle beam therapy system. 4. A cut-out portion is prepared by preparing a plurality of types of top plates arranged at different positions so that the cut-out portion can be adjusted to the affected area to be irradiated. The particle beam therapy system according to any one of claims 1 to 3, characterized in that: 5. The particle beam therapy system according to claim 1, wherein a beam shaping device such as a filter or a collimator is attached to the notched portion of the top plate. 6. A top plate is provided so as to project in the longitudinal direction of the top plate, and a block divided into the support rod is fitted into the top plate to form a top plate and at the same time a notch is formed. The particle beam therapy system according to any one of claims 1 to 5. 7. The particle beam according to claim 6, wherein a spacer is interposed between the blocks so that a place where the hole-shaped notch is formed can be arranged at an arbitrary position depending on the order of the block and the spacer. Treatment device. 8. A hole-shaped notch is used, so that the hole-shaped notch can be arranged at a free position depending on the order of the blocks.
The described particle beam therapy system. 9. A block with a collimator or a filter is used as the block having a hole-shaped notch,
9. The particle beam therapy system according to claim 8, wherein the block can be arranged at any position. 10. A recessed cutout is formed in advance on the lower surface of the block so that the depth of the particle beam matches the thickness of the portion through which the block beam passes, in conformity with the shape of the affected area. The particle beam therapy system according to claim 9. 11. The particle beam therapy system according to claim 10, wherein all the divided blocks are made of the same material.