JP2001346893A - Radiotherapeutic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiotherapeutic apparatus which achieves an easier access thereto by a patient with a smaller occupying volume and an inexpensive implementation. SOLUTION: The apparatus is equipped with a rotary gantry 16 installed rotatably about a rotating shaft 15, a synchrotron 22 which is provided with a particle generator 20 and a particle accumulation ring 21 and carried on the rotary gantry 16 and an irradiation field former 25 carried on the rotary gantry 16 so as to guide a corpuscular beam to an irradiation field along the irradiation axis 24 crossing the rotating shaft 15 and a deflection magnet 26 which deflects the corpuscular beam, supplied from the synchrotron 22, in the direction of the irradiation axis 24 to be guided to the irradiation field former 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiotherapy apparatus using a particle beam such as a proton beam or a heavy particle beam, and more particularly to a radiotherapy device which occupies a small volume, can be implemented at low cost, and is easily accessible to a patient. It concerns the device.

[0002]

2. Description of the Related Art Conventionally, X-rays have been used for radiotherapy. In recent years, radiotherapy using proton beams or heavy ion beams has been considered. Proton beam or heavy ion beam is X
Since the irradiation dose distribution is superior to that of X-rays, there is an advantage that irradiation can be accurately performed on an affected tumor (elimination of unnecessary irradiation to a healthy part), and there is an advantage that there are few complications. For this reason, the practical use of radiation therapy apparatuses using proton beams or heavy particle beams (hereinafter collectively referred to as particle beams) has been promoted.

[0003] An outline of a conventional radiotherapy apparatus will be described.

As shown in FIG. 2, a conventional radiotherapy apparatus is a synchrotron 4 comprising a particle generator 1 and a particle storage ring 2 provided with a deflecting magnet 2a to accelerate particles in a ring shape. Is installed in the particle beam source chamber 3, and the irradiation chamber 5 remote from the particle beam source chamber 3 is provided with a rotating gantry 7 having a ring structure rotatable around the horizontal axis 6 by 360 °.

FIG. 2 shows a case in which a rotating gantry 7 is provided in each of the two irradiation chambers 5, and a diverging magnet provided with a particle beam from the synchrotron 4 in a transport chamber 8. 9 to each rotating gantry 7. Further, in FIG. 2, a horizontal irradiation chamber 10 having no rotating gantry 7 is also provided, and 11 in the figure is a beam dump.

As shown in FIG. 3, the rotating gantry 7 is irradiated with a particle beam along an irradiation axis 12 orthogonal to the horizontal axis 6 in a desired cross-sectional shape and depth range (such a three-dimensional range is irradiated). An irradiation field forming device 13 for guiding the particle beam from the synchrotron 4 to the rotating gantry 7 via the transport chamber 8 is directed outward from the horizontal axis 6. And a deflection magnet 14b for deflecting the particle beam in a direction orthogonal to the horizontal axis 6 and guiding the particle beam to the irradiation axis 12.

The particle beam supplied from the synchrotron 4 and branched by the deflecting magnet 9 is supplied to the deflecting magnet 14.
a of the irradiation field forming device 13 is deflected in a direction away from the horizontal axis 6 by a, and further deflected in a direction orthogonal to the horizontal axis 6 by a deflection magnet 14b.
In the direction of. The irradiation field forming device 13 irradiates the desired irradiation field with the particle beam by enlarging or reducing the width of the particle beam, adjusting the intensity and distribution of the particle beam energy, and controlling the contour of the particle beam. The intersection between the irradiation axis 12 and the horizontal axis 6 is called an isocenter, and the particle beam passes through the isocenter regardless of the rotation angle of the rotating gantry 7.

[0008] The patient A is usually placed on the treatment bed 14 in a supine position (upright position), and receives treatment in a state in which an axis passing through the head and feet (hereinafter referred to as a body axis) substantially overlaps the horizontal axis 6. The particle beam is irradiated at right angles to the body axis regardless of the rotation angle of the rotating gantry 7. By rotating the rotating gantry 7, the particle beam can be emitted from an arbitrary angle in the circumferential direction of the body axis. In the radiation therapy using a particle beam, the irradiation angle is not changed while irradiating the particle beam, and the irradiation is performed at a desired irradiation angle planned in advance. In other words, one irradiation is performed only in one direction.

[0009] This type of radiotherapy apparatus is available from US LLUM.
C (Loma-Linda University M
medical Center Loma Linda University Hospital),
US MGH (Massachusetts Generator)
al Hospital Massachusetts General Hospital) and the National Cancer Center.

[0010]

However, these conventional radiotherapy apparatuses have a drawback that they are large and expensive, and this drawback has hindered the spread of this apparatus. For example, a rotating gantry for X-ray therapy has a cubic volume of about 2.5 m on a side, whereas a conventional rotating gantry 7 for particle beam therapy is huge, having a diameter of 10 m and a length of 10 m. . Further, the synchrotron 4 is also large, having a size of 6 m × 6 m, and further requires a transport chamber 8 for guiding the particle beam from the synchrotron 4 to the rotating gantry 7.

Therefore, in order to use such a radiation therapy apparatus, it is necessary to secure a vast installation space,
Also, the equipment cost is enormous. These factors made it difficult to spread.

Further, the conventional radiotherapy apparatus requires a huge underfloor space which is close to half of the occupied volume, so that the construction cost of the building is increased. Because the bed 14 is located, it is difficult to access the patient A.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a radiotherapy apparatus which solves the above-mentioned problems, occupies a small volume, can be implemented at low cost, and has easy patient access.

[0014]

SUMMARY OF THE INVENTION The present invention provides a rotating gantry provided rotatably about a rotating shaft, a synchrotron mounted on the rotating gantry having a particle generator and a particle storage ring, and a rotating shaft. An irradiation field forming apparatus mounted on a rotating gantry so as to guide a particle beam to an irradiation field along an irradiation axis intersecting with the irradiation field; and deflecting a particle beam supplied from the synchrotron in the direction of the irradiation axis to form the irradiation field. A radiation therapy apparatus, comprising: a deflection magnet for guiding the apparatus.

In the above means, the particle generator may be arranged inside the ring shape of the storage ring, and particles from the particle generator may be guided to the storage ring via the deflection magnet. The rotating axis of the rotating gantry may be inclined with respect to the horizontal, the rotating axis of the rotating gantry may be inclined at 45 ° with respect to the horizontal, and the irradiation axis may be inclined at 45 ° with respect to the rotating axis. Is also good.

In the present invention, a compact radiotherapy apparatus is configured by mounting a synchrotron and an irradiation field forming device on a rotating gantry rotatably provided around a rotation axis. The installation space for the treatment device can be significantly reduced, and the price of the device can be significantly reduced. Therefore, the use and spread of the radiation treatment device can be greatly increased.

Further, since the particle generator is arranged inside the ring shape of the storage ring and the particles from the particle generator are guided to the storage ring via the deflecting magnet, the configuration of the synchrotron can be further reduced. Can be

Further, for example, if the rotation axis of the rotating gantry is inclined by 45 ° with respect to the horizontal and the irradiation axis is inclined by 45 ° with respect to the rotation axis, the space required for the rotational movement is further reduced, and furthermore, the underfloor is further reduced. Since no space is required, the cost of the building is low, and the access to the patient is facilitated because the treatment bed is placed on the floor.

[0019]

An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention. In this radiation therapy apparatus, a rotating gantry 16 rotatably provided around a rotating shaft 15 is provided in an irradiation chamber 17. The rotating gantry 16 shown in FIG. 1 has a substantially frusto-conical ring shape and is inclined. The lower end of the large diameter side is rotatably supported by a receiving roller 18 provided on the floor, and the upper end of the small diameter side is irradiated. It is rotatably supported by a support member 19 provided in the chamber 17. The rotating gantry 16 in FIG.
Is inclined at an angle of 45 ° with respect to the horizontal.

A synchrotron 22 having a particle generator 20 and a particle storage ring 21 is mounted on the upper end of the rotating gantry 16 on the small diameter side. Particle storage ring 21
Is provided with a deflecting magnet 21a so as to accelerate particles in a ring shape.
Are configured such that the diameter of the ring shape is as small as possible.

Further, the particle generator 20 is arranged so as to be positioned inside the ring shape of the particle storage ring 21, and particles emitted from the particle generator 20 are transferred to the particle storage ring 21 via the deflection magnet 23. Let me be guided. Thereby, the installation space of the particle generator 20 can be reduced, and the configuration of the synchrotron 22 can be further reduced.

At the lower end on the large diameter side of the rotating gantry 16,
An irradiation field forming device 25 for guiding a particle beam to an irradiation field along an irradiation axis 24 crossing the rotation axis 15 is mounted. Further, there is provided a deflection magnet 26 which deflects the particle beam taken out from the particle beam take-out part 22a of the synchrotron 22 in the direction of the irradiation axis 24 and guides it to the irradiation field forming device 25.

At this time, the irradiation field forming device 25 is attached to the rotating gantry 16 at an angle so that the particle beam is directed toward the rotating shaft 15 at an angle of 45 ° with respect to the rotating shaft 15. Thereby, the rotation axis 15 of the rotating gantry 16 is inclined at 45 °, and the irradiation axis 24 of the irradiation field forming device 25 is inclined at 45 ° with respect to the rotating axis 15, so that the rotating gantry 16 is rotated. By rotating the irradiation axis 16, the irradiation axis 24
Is the vertical direction indicated by a solid line in FIG.
It can be adjusted in any direction between the horizontal direction indicated by the two-dot chain line.

However, the inclination angle of the rotating shaft 15 of the rotating gantry 16 is not limited to 45 °, and the mounting angle of the irradiation field forming device 25 with respect to the rotating shaft 15 is also 45 °.
The present invention is not limited to this, and can be set arbitrarily.

According to the above radiation therapy apparatus, the rotating gantry 16 has the synchrotron 22 and the irradiation field forming apparatus 25.
The size of the entire configuration mounted with, for example, could be accommodated in a volume of about 2 m. Thus, the radiation therapy apparatus of the present invention can be installed in an extremely small space as compared with the related art, and can perform treatment by irradiation and the like.

The operation of the above embodiment will be described.

In the radiotherapy apparatus shown in FIG. 1, particles emitted from the particle generator 20 are supplied to the particle storage ring 21 of the synchrotron 22 by the deflecting magnet 23 and orbit inside the particle storage ring 21 to be accelerated. . The accelerated particle beam is taken out from the particle beam take-out section 22a, deflected by the deflecting magnet 26, and irradiated with the irradiation field forming device 25.
Is supplied to the irradiation field forming device 25 along the irradiation axis 24. The irradiation field forming device 25 irradiates the desired irradiation field with the particle beam by enlarging or reducing the width of the particle beam, adjusting the intensity and distribution of the particle beam energy, and regulating the contour of the particle beam.

In the radiotherapy apparatus shown in FIG. 1, the rotation axis 15 of the rotary gantry 16 is inclined by 45 ° with respect to the horizontal, and the irradiation axis 24 of the irradiation field forming apparatus 25 is rotated 45 degrees with respect to the rotation axis 15.
Due to the inclination, the irradiation axis 24 changes from 90 ° to 0 ° with respect to the horizontal. At this time, the path length from the radiation source to the isocenter is constant regardless of the rotation angle of the rotating gantry 16.

The patient A is treated on the treatment bed 14, for example, in a supine position. Therefore, irradiation axis 2
The solid angle 4 continuously forms different solid angles from a right angle to a body axis depending on the rotation angle of the rotating gantry 16. By setting the rotation gantry 16 to an arbitrary rotation angle,
The particle beam can be irradiated at an arbitrary solid angle with respect to the body axis. However, this radiation therapy apparatus cannot irradiate the patient A with a particle beam from below. Therefore, for example, in the case where a patient in a supine position is conventionally irradiated with particle beams from below, the radiation therapy apparatus of the present invention irradiates a patient in a prone position (prone) with particle beams from above. An equivalent effect can be obtained. As described above, since the irradiation angle is not changed while irradiating the particle beam, such a method is possible.

On the other hand, as described above, the radiotherapy apparatus shown in FIG. 1 can have a small structure of, for example, about 2 m × 2 m.
Even when 5 is installed horizontally, patient access does not become difficult, so that it is possible to easily irradiate the particle beam from below the patient A as in the conventional method.

In this radiotherapy apparatus, the treatment bed 1
4 may be configured to be movable. For example, three-axis linear motion and three
The posture and position of the patient A are arbitrarily set using a six-axis movable bed capable of rotating the shaft. Thereby, any part of the patient A can be located at the isocenter, and any irradiation (Coplanar irradiation and Non-C irradiation) can be performed.
oplanar irradiation).

The operator who performs the radiation therapy has a CT
Based on the tomographic images taken by the device, the affected part is identified, the irradiation angle and irradiation field are planned so that the most effective and healthy part is not irradiated unnecessarily, and the rotating gantry is set according to this irradiation angle. The rotation angle of 16 is set, and the irradiation field of the irradiation field forming device 25 is set.

The above-described radiotherapy apparatus of the present invention can solve all the problems of the occupied volume, cost, and patient access of the conventional radiotherapy apparatus. Further, since the rotating gantry 16 is supported by the ring structure, smooth rotation similar to that of the related art can be obtained.

It should be noted that the present invention is not limited to the above embodiment, and various changes can be made without departing from the gist of the present invention.

[0036]

According to the present invention, a compact radiotherapy apparatus is configured by mounting a synchrotron and an irradiation field forming apparatus on a rotating gantry rotatably provided around a rotation axis. In comparison with this, it is possible to greatly reduce the installation space for the radiation therapy apparatus, and to significantly reduce the price of the apparatus, thereby significantly increasing the use and spread of the radiation therapy apparatus.

Further, since the particle generator is arranged inside the ring shape of the storage ring and the particles from the particle generator are guided to the storage ring via the deflection magnet, the configuration of the synchrotron can be further reduced. There is an effect that can be converted.

Further, for example, when the rotation axis of the rotating gantry is inclined at 45 ° with respect to the horizontal and the irradiation axis is inclined at 45 ° with respect to the rotation axis, the space required for the rotational movement is further reduced, and furthermore, the space under the floor is reduced. Since no space is required, the cost of the building is reduced, and the treatment bed is arranged on the floor, so that there is an effect that the patient can be easily accessed.

[Brief description of the drawings]

FIG. 1 is a side view showing a schematic configuration of a radiotherapy apparatus of the present invention.

FIG. 2 is a plan view showing the entire configuration of a conventional radiation therapy apparatus.

FIG. 3 is a side view of a rotating gantry part in a conventional radiation therapy apparatus.

[Explanation of symbols]

 REFERENCE SIGNS LIST 15 rotating shaft 16 rotating gantry 20 particle generator 21 particle storage ring 22 synchrotron 23 deflection magnet 24 irradiation axis 25 irradiation field forming device 26 deflection magnet

Claims (4)

[Claims] 1. A rotating gantry rotatably provided around a rotating axis, a synchrotron mounted on the rotating gantry having a particle generator and a particle storage ring, and along an irradiation axis intersecting the rotating axis. An irradiation field forming device mounted on a rotating gantry so as to guide the particle beam to the irradiation field, and a deflection magnet for deflecting the particle beam supplied from the synchrotron in the direction of the irradiation axis and guiding the particle beam to the irradiation field forming device. A radiation treatment apparatus comprising: 2. The storage device according to claim 1, wherein the particle generator is arranged inside the ring shape of the storage ring, and the particles from the particle generator are guided to the storage ring via a deflection magnet. A radiation therapy apparatus according to claim 1. 3. The radiotherapy apparatus according to claim 1, wherein the rotation axis of the rotating gantry is inclined with respect to the horizontal. 4. The rotation axis of the rotating gantry is set at 4 degrees with respect to the horizontal.
5 ° tilt and the irradiation axis at 45 ° to the rotation axis
The radiotherapy apparatus according to claim 3, wherein the radiotherapy apparatus is inclined.