JP2017055958A - Particle beam medical device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a corpuscular beam treatment apparatus capable of supporting a movable floor only by a rotary gantry side without depending on the stiffness of a building side which fixes a movable bed.SOLUTION: A corpuscular beam treatment apparatus 10 comprises: an annular movable floor group 12 formed by joining a plurality of elongated floor plates together at side edge portions of each floor plate; a pair of a first guide 13A and a second guide 13B for slidably engaging both ends of the movable floor group 12 in a closed orbit, the closed orbit being formed of a circular arc and a straight line; a support portion 30 for rotatably supporting the first guide 13A from an inner peripheral surface of the rotary gantry 15 such that the rotation symmetry axis of the circular arc of the closed orbit is aligned with the rotation axis Z of the rotary gantry 15; a rotation drive portion 23 for abutting against an outer peripheral surface of the rotary gantry 15 and rotating the movable floor group 12, with an irradiation port 18 of a beam extending through the rotary gantry 15 mounted on a first base 21 and the movable floor group 12; and a connection portion 40 for preventing the corotation of the first guide 13A which is apt to follow the rotation of the rotary gantry 15, by connecting the support portion 30 to a second base 22 with a bed 24 mounted thereon, the bed being used to align a patient with the sights of the irradiation port 18.SELECTED DRAWING: Figure 2

Description

  Embodiments described herein relate generally to a particle beam medical device having a rotating gantry.

2. Description of the Related Art Particle beam therapy is widely performed in which treatment is performed by irradiating an affected area (cancer) of a patient with a particle beam such as protons or carbon ions.
As one of such particle beam therapy methods, a patient lying on a treatment bed is positioned and irradiated with a particle beam in a treatment room formed inside a large rotating mechanism (hereinafter referred to as a rotating gantry). There is something to do.

A particle beam medical device equipped with such a rotating gantry is capable of rotating a radiation port fixed to the rotating gantry or displacing a treatment bed in a treatment room, so that a particle beam beam can be applied to an affected area of a patient from an arbitrary direction. Is irradiated.
The treatment room formed inside the rotating gantry is formed by a moving floor having a horizontal and flat floor surface regardless of the rotational position of the rotating gantry.

By forming the treatment room with such a moving bed, continuity and integrity between the space where the treatment bed is fixed and the space where the particle beam is irradiated are ensured. Thereby, improvement of workability | operativity of a medical worker and reduction of a patient's feeling of mental pressure can be aimed at.
Conventionally, the movable floor supports one of the two guides engaging with both ends thereof on the rotating gantry side and the other on the building side to which the treatment bed is fixed. Further, one guide supported on the rotating gantry side is maintained in a stationary posture by a motor that rotates in reverse and synchronous with the rotating gantry.

JP 11-47287 A

In recent years, many requests have been made to increase the internal space of the treatment room.
However, in the conventional method of supporting one end of the moving floor from the building side, there is a problem that the floor plate constituting the moving floor becomes long and it is difficult to ensure the strength.
Moreover, even when the strength on the building side is insufficient, there is a problem that the support of one end of the moving floor becomes unstable.
In this way, if the strength of the moving floor or its supporting structure is insufficient, the floor board will sink, etc., and the roller running on the guide will be caught, preventing the floor board from moving smoothly, abnormal noise, stagnation, failure Was caused.

Furthermore, when performing maintenance of the devices arranged under the floor of the moving floor, there is a problem that it takes time to remove the floor board from the moving floor supported at one end from the building side.
Furthermore, when reassembling the floor board from which the movable floor is removed, there is a problem that the structure that is supported from the building side reduces the work efficiency when the alignment adjustment of the rotating shaft is performed.

  The embodiment of the present invention has been made in consideration of such circumstances, and a particle beam medical device capable of supporting the moving bed only on the rotating gantry side without depending on the rigidity of the building side fixing the moving bed. The purpose is to provide.

  The particle beam medical device according to the embodiment includes a moving bed group in which a plurality of longitudinal floor boards are connected to each other at each side edge to form an annular shape, and both ends of the moving bed group are closed orbits formed of arcs and straight lines. A pair of first and second guides that are slidably engaged, and the first guide from the inner peripheral surface of the rotating gantry so that the rotationally symmetric axis of the arc of the closed track coincides with the rotating axis of the rotating gantry. A support unit that rotatably supports the rotation gantry, and a rotation drive unit that is provided on the first foundation and rotates in contact with the outer peripheral surface of the rotating gantry in a state where a beam irradiation port penetrates the rotating gantry and the moving bed group. A connecting portion for connecting the support portion to a second base provided with a bed for aligning a patient to the aim of the irradiation port and preventing the first guide from following the rotation of the rotating gantry; With It is characterized in.

  The embodiment of the present invention provides a particle beam medical device that can support the moving bed only on the rotating gantry side without depending on the rigidity of the building side that fixes the moving bed.

1 is an external view of a particle beam medical device according to an embodiment of the present invention. (A) The front view of the particle beam medical device which concerns on embodiment, (B) The side surface fragmentary sectional view of the particle beam medical device which concerns on embodiment. The top view of the connection part applied to the particle beam medical device which concerns on embodiment.

Hereinafter, a particle beam medical device according to an embodiment of the present invention will be described based on the accompanying drawings.
As shown in FIG. 1, the particle beam medical device 10 includes a moving bed group 12 in which a plurality of longitudinal floor plates 11 are connected to each other at each side edge to form an annular shape, and both ends of the moving bed group 12 are formed with arcs and A pair of first guide 13A and second guide 13B (FIG. 2) that are slidably engaged in a closed track formed of a straight line, and the rotationally symmetric axis of the arc of the closed track coincide with the rotation axis Z of the rotating gantry 15. A support portion 30 (FIG. 2) for rotatably supporting the first guide 13A from the inner peripheral surface 15a of the rotating gantry, and a beam irradiation port 18 provided on the rotating gantry 15 and the moving bed group 12 provided on the first foundation 21. The support unit 30 is connected to the second base 22 provided with the rotation drive unit 23 that rotates in contact with the outer peripheral surface of the rotating gantry 15 in a state of being penetrated, and the bed 24 that positions the patient at the aim of the irradiation port 18. Rotating gantry 1 Connecting portions to prevent co-rotation of the first guide 13A to be follow the rotary 40 is provided (FIG. 2), a.

  As shown in FIG. 1, the rotating gantry 15 is a large structure having a generally cylindrical shape, and is rotated around the rotation axis (Z axis) by the rotation of a plurality of rotation driving units 23 circumscribing the outer peripheral surfaces of both edges. Rotate to. The weight of the rotating gantry 15 is supported by the first base 21 via the rotation driving unit 23.

In addition to the irradiation port 18 of the particle beam 19, the rotating gantry 15 is provided with a large number of beam transport systems, beam deflecting electromagnets, and other control devices and structures (not shown). .
The particle beam 19 is generated by accelerating ions (heavy particles or proton ions) generated by an ion source (not shown) by a linear accelerator, and then entering a circular accelerator (not shown) and increasing the energy to a set energy. .

The particle beam output from the circular accelerator is incident on an extension line of the rotation axis Z of a beam transport system (not shown) provided to rotate integrally with the rotating gantry 15.
The particle beam thus incident on the beam transport system is irradiated to a patient lying on the bed 24 from the irradiation port 18 with its trajectory bent by a deflecting electromagnet.

The bed 24 has a base fixed to the second foundation 22 (building), moves inside the rotating gantry 15, and positions the affected area of the patient at the irradiation position of the particle beam 19.
When the particle beam 19 is irradiated toward the affected area, it loses kinetic energy when passing through the body of the patient, and the speed is reduced, and the resistance is almost inversely proportional to the square of the speed, and the speed is reduced to a certain speed. Then it stops suddenly.
In the vicinity of the stop point of the particle beam 19, high energy called a Bragg peak is emitted. Since the bed 24 is positioned so that the release position of the Bragg peak coincides with the affected area, only the affected tissue is killed and a treatment with less damage to the normal tissue is performed.

Each of the floor plates 11 constituting the movable floor group 12 is desired to have a large flexural rigidity in the longitudinal direction and be lightweight. The plurality of floor plates 11 are connected to each other at their side edges so that they can be bent, and further, the starting end and the ending end are also connected to form an annular sheet having an indeterminate cross section with respect to the longitudinal direction.
The first guide 13 </ b> A and the second guide 13 </ b> B have a tunnel-shaped closed track formed of an arc and a straight line. The closed tracks formed in the first guide 13A and the second guide 13B can engage the moving bed group 12 at both ends thereof and can move relative to each other slidably.

As a result of each of both ends of the moving bed group 12 engaging and being held by the closed tracks of the first guide 13A and the second guide 13B, the internal space of the moving bed group 12 is a tunnel shape surrounded by a plane and a curved surface. Will have.
The movable bed group 12 can rotate around the rotation axis Z while maintaining the tunnel shape with the first guide 13A and the second guide 13B being stationary in the space.

The moving bed group 12 can be rotated in synchronism with the rotation of the rotating gantry 15 by penetrating the irradiation port 18 through a hole provided in a part of the moving bed group 12.
By this moving floor group 12, a flat and horizontal floor surface can be formed inside the rotating gantry without depending on the rotational position of the irradiation port 18.
The flat horizontal floor surface of the moving floor group 12 serves as a work space necessary for a medical worker to access a patient lying on the bed 24.

As shown in FIG. 2, the first guide 13 </ b> A located on the entrance side of the treatment room has an inner circumferential surface of the rotating gantry 15 such that the rotational symmetry axis of the arc coincides with the rotating axis Z of the rotating gantry 15. Is provided with a support portion 30 that supports the shaft so as to be rotatable.
The support portion 30 is arranged in a radial direction from the outer periphery of the first guide 13A, and a plurality (three in the drawing) of rolling elements 31 (31a, 31b, 31c) rotating in contact with the inner peripheral surface of the rotating gantry 15 are provided. And at least one of these rolling elements 31 (reference numeral 31a) is provided on the expansion member 32 extending vertically from the straight portion of the first guide 13A.
And the 1st guide groove 45 which guides the rolling element 31 to rotate is provided in the internal peripheral surface 15a of the rotating gantry which the rolling element 31 (31a, 31b, 31c) of the support part 30 contact | abuts.

  The rolling element 31a provided on the expansion member 32 receives the load of the first guide 13A and prevents the rotation of the first guide 13A along with the other rolling elements 31b and 31c. As described above, the first guide 13A is supported by the inner peripheral surface 15a of the rotating gantry, so that the rotation of the moving bed group 12 can be performed without considering the relative positional relationship with the second foundation 22 (building). Alignment adjustment can be performed, which contributes to improving the efficiency of maintenance work.

  In addition, since the first guide 13A can be disposed close to the second guide 13B, the length of the floor plate 11 in the longitudinal direction can be shortened to improve its flexural rigidity. The gap between the second foundation 22 and the first guide 13 </ b> A that occurs at this time can be eliminated by bridging the bridge plate 53 with the adjusted width.

The crossover plate 53 can be detachably connected at both ends to the straight portion of the first guide 13 </ b> A and the second foundation 22. Thereby, after all the adjustment work concerning installation is complete | finished, the clearance gap between the 2nd foundation 22 and the 1st guide 13A can be filled, removal is also easy, and it contributes to the improvement of maintenance property.
Furthermore, since the gap can be filled only by changing the size of the transition board 53 without changing the shape of the moving floor group 12 at all, the degree of freedom in designing the installation interval of the second foundation 22 and the rotating gantry 15 is improved. be able to.

  In addition, the structure of the support part 30 is not limited to the form shown in figure, The shape of the rolling element 31 contact | abutted to a radial direction may be a sphere other than the case of a wheel, and the number is 3 or more. Can be. Further, without using such a rolling element 31, the inner peripheral surface 15a of the rotating gantry and the first guide 13A can be brought into contact with each other with a low friction sliding member.

A panel 51 (FIG. 2B) is provided in the second guide 13B located on the depth side of the treatment room so as to close the opening. The panel 51 is supported by a bearing 52 that freely rotates in accordance with the rotation axis Z of the rotating gantry 15, and the second guide 13B is disposed at a position that is mirror-symmetric with respect to the first guide 13A. .
One end of the bearing 52 is fixed to the inner peripheral surface 15a of the rotating gantry, and the other end that supports the panel 51 does not need to be driven to rotate, and may be any one that freely rotates.

In other words, the second guide 13B cooperates with the opposing first guide 13A to slidably hold both ends of the movable floor group 12 having high flexural rigidity. For this reason, even if the first guide 13A is made stationary in the space and the moving bed group 12 is relatively rotated, the stationary state of the second guide 13B is maintained.
Therefore, even if the rotating gantry 15, the irradiation port 18, and the moving bed group 12 rotate synchronously, as long as the first guide 13A remains stationary, the second guide 13B also remains stationary.
In this state, the bearing 52 supports the second guide 13 </ b> B so as not to be displaced in the axial direction of the rotation axis Z and the direction orthogonal thereto while rotating together with the rotating gantry 15.

In the above description, the separation is prevented by the structure in which both ends of the moving bed group 12 are sandwiched between the pair of first guide 13A and second guide 13B.
Here, the case where the closed track of the first guide 13A and the second guide 13B has a structure that engages so as not to separate both ends of the moving bed group 12 will be considered.
In this case, the external force (including gravity) applied to the second guide 13B is supported by the first guide 13A via the moving bed group 12. For this reason, the bearing 52 that supports the second guide 13B on the rotating gantry 15 side is not an essential component.

On the other hand, since the support portion 30 of the first guide 13A has a frictional force with respect to the inner peripheral surface 15a of the rotating gantry, it tends to follow this when the rotating gantry 15 rotates.
For this reason, while the rotating gantry 15 is rotating, the level of the floor surface of the moving floor group 12 may not be maintained.
Therefore, in order to prevent the first guide 13 </ b> A from following the rotation of the rotating gantry 15, a connecting portion 40 that connects the second foundation 22 and the support portion 30 is provided.

  As shown in FIG. 3, the connecting portion 40 is provided on the surface of the second base 22 facing the expansion member 32, and is in contact with the inner peripheral surface 15 a of the rotating gantry at one end to synchronize with the rotation of the rotating gantry 15. The first rotating body 41 that rotates, the belt 43 that circumscribes and synchronizes with the other end of the first rotating body 41, and the surface of the expansion member 32 that faces the second foundation 22 are provided at one end. A second rotating body 42 that circumscribes the belt 43 and constrains the distance from the first rotating body 41 within a predetermined value and makes the other end that rotates synchronously with the first rotating body 41 contact the inner peripheral surface 15a of the rotating gantry. And have.

The first rotating body 41 is rotatably provided on a first block 56 a that is fixed to a column 55 a that extends in the vertical direction from the surface of the second foundation 22. Since one end of the first rotating body 41 is in contact with the inner peripheral surface 15a of the rotating gantry, the first rotating body 41 prevents the rotating gantry 15 from being lifted and rotates synchronously.
The second rotating body 42 is rotatably provided on a second block 56b that is fixed to a column 55b that extends in the vertical direction from the surface of the expansion member 32. Since one end of the second rotating body 42 is in contact with the inner peripheral surface 15 a of the rotating gantry, the second rotating body 42 rotates in synchronization with the rotating gantry 15.

Since the belt 43 circumscribes the other end of the first rotator 41 and one end of the second rotator 42, the belt 43 is constrained to a predetermined value while rotating. As a result, the first guide 13 </ b> A trying to rotate following the rotating gantry 15 can be stopped by the tension of the belt 43.
Specifically, the other end of the first rotating body 41 and one end of the second rotating body 42 are configured by sprockets, and the belt 43 is configured by a chain that meshes with the tooth profile of the sprocket.

A second guide groove 46 is provided on the inner peripheral surface 15a of the rotating gantry where one end of the first rotating body 41 and the other end of the second rotating body 42 abut against each other to rotate and move the rotating bodies 41 and 42. It has been. Specifically, one end of the first rotating body 41 and the other end of the second rotating body 42 are configured by sprockets, and the second guide groove 46 is configured by a rack that meshes with the tooth profile of the sprocket.
When a rotational force in the direction opposite to the following rotation is applied to the first guide 13A, the first block 13a and the second block 56b are in contact with each other, thereby preventing the first guide 13A from rotating backward. The

  By configuring the connecting portion 40 in this manner, the connection between the second foundation 22 side and the support portion 30 of the movable floor group 12 is released simply by removing the belt 43, contributing to improvement in workability during maintenance. To do.

  According to the particle beam medical device of at least one embodiment described above, the moving bed is fixed by providing a structure that rotatably supports a guide that is slidably engaged with one end of the moving bed with respect to the rotating gantry. It is possible to support the moving floor only on the rotating gantry side without depending on the rigidity of the building side.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Particle beam medical device, 11 ... Floor board, 12 ... Moving bed group, 13A ... 1st guide, 13B ... 2nd guide, 15 ... Rotating gantry, 15a ... Inner peripheral surface of rotating gantry, 18 ... Irradiation port, 19 ... Particle beam, 21 ... first foundation, 22 ... second foundation, 23 ... rotation drive, 24 ... bed, 30 ... support, 31 (31a, 31b, 31c) ... rolling element, 32 ... expansion member, 40 ... Connecting part 41 ... first rotating body 42 ... second rotating body 43 ... belt 45 ... first guide groove 46 ... second guide groove 51 ... panel 52 ... bearing 53 ... crossover plate 55a ... post , 55b ... struts, 56a ... first block, 56b ... second block.

Claims (7)

A plurality of longitudinal floor boards are connected to each other at each side edge to form a moving floor group,
A pair of first guides and second guides slidably engaged with each other at both ends of the moving bed group in a closed track made of an arc and a straight line;
A support portion that rotatably supports the first guide from the inner peripheral surface of the rotating gantry so that the rotationally symmetric axis of the arc of the closed track coincides with the rotating axis of the rotating gantry;
A rotation driving unit provided on the first foundation, rotating in contact with an outer peripheral surface of the rotating gantry in a state where a beam irradiation port is passed through the rotating gantry and the moving bed group;
A connecting portion for connecting the support portion to a second foundation provided with a bed for aligning a patient with the aim of the irradiation port, and for preventing the first guide from following the rotation of the rotating gantry. A particle beam medical device comprising: The particle beam medical device according to claim 1,
The support part is
A plurality of rolling elements arranged radially from the outer periphery of the first guide and rotating in contact with the inner peripheral surface of the rotating gantry;
At least one of the rolling elements is provided on an expansion member that extends in a vertical direction from the straight portion of the first guide. The particle beam medical device according to claim 2,
The connecting portion is
A first rotating body that is provided on the surface of the second foundation facing the expansion member, abuts against the inner peripheral surface of the rotating gantry at one end, and rotates in synchronization with the rotation of the rotating gantry;
A belt that circumscribes the other end of the first rotating body and rolls synchronously;
Provided on the surface of the expansion member facing the second foundation, circumscribing the belt at one end to restrain the distance from the first rotating body within a predetermined value, and rotating in synchronization with the one rotating body A particle beam medical device comprising: a second rotating body whose end abuts against an inner peripheral surface of the rotating gantry. In the particle beam medical device according to claim 2 or 3,
The particle beam medical device according to claim 1, wherein a first guide groove for guiding the rotating body that rotates is provided on an inner peripheral surface of the rotating gantry with which the rolling body abuts. In the particle beam medical device according to claim 3 or 4,
On the inner peripheral surface of the rotating gantry where one end of the first rotating body and the other end of the second rotating body abut, a second guide groove for guiding each rotating body that rotates is provided. A particle beam medical device. In the particle beam medical device according to any one of claims 1 to 5,
The second guide is provided with a panel so as to close the opening,
The particle beam medical device, wherein the panel is supported by a bearing that freely rotates in accordance with a rotation axis of a rotating gantry. The particle beam medical device according to any one of claims 1 to 6,
A particle beam medical device, further comprising a transition plate that connects both ends to the straight portion of the first guide and the second foundation, and fills a gap between the second foundation and the first guide.

Images