JP2019217422A - Particle beam treatment apparatus - Google Patents

Abstract

To provide a particle beam treatment apparatus that can acquire an X-ray image having good quality with a simple configuration and requires short treatment time, an operation method therefor, and a movable plate.SOLUTION: A particle beam treatment apparatus 10 comprises: a particle beam irradiation machine 16 for emitting a particle beam B; a rotary gantry 21 that supports the particle beam irradiation machine 16; a movable bed that is constituted by a plurality of movable plates 37 in a rotary gantry 21's revolving direction and forms a horizontal part below a top plate 18 on which a body to be irradiated is placed; an X-ray generator 27a for generating an X-ray; and an X-ray detector 27b for detecting the X-ray arriving through the movable bed. At least one of the movable plates 37 comprises: a first bed member for transmitting the X-ray so that the X-ray can be detected by the X-ray detector 27b; and a second bed member having an X-ray transmission factor smaller than that of the first bed member. The first bed member and the second bed member are made of the same material and a first bed member's thickness is thinner than a second bed member's thickness.SELECTED DRAWING: Figure 3

Description

  Embodiments of the present invention relate to a particle therapy technique provided with a rotating gantry.

  2. Description of the Related Art In recent cancer treatments, a particle beam therapy method of irradiating an affected part with a particle beam obtained by accelerating charged particles such as protons or carbon ions to high energy is widely used.

In this particle beam therapy method, in order to irradiate a cancer affected part with a particle beam while avoiding an important organ, it is required to irradiate while changing the irradiation angle of the beam in various ways.
Thus, for example, the particle beam irradiation machine is fixed to a cylindrical rotating gantry, and the irradiation angle is changed by rotating the entire rotating gantry particle beam irradiation machine.

A moving floor that maintains a horizontal and flat floor surface regardless of the rotation of the rotating gantry is provided in the internal space of the rotating gantry that serves as a treatment room.
Using this moving bed, a technician accesses the patient before and after treatment, or the patient gets off the treatment table in an emergency.
The moving bed slides along the distal end of the particle beam irradiation device so as not to hinder the displacement of the distal end fixed to the treatment room at the distal end of the particle beam irradiation machine.

Before and during the irradiation of the particle beam, X-ray imaging is performed to accurately grasp the position and shape of the affected part.
Therefore, in the treatment space, an X-ray generator that irradiates the patient with X-rays and an X-ray detector that detects X-rays transmitted through the patient (hereinafter, referred to as “X-ray imaging device”) are arranged.
As described above, since the particle beam therapy system includes a plurality of devices whose relative positions change, it is necessary to consider the change in the relative positions when arranging the X-ray imaging devices.

For example, there is known a method in which an arm is connected to an X-ray imaging device at a location where it does not collide with any device in a treatment room and stored together with the arm.
In this case, the X-ray generator is arranged near the affected part while taking an image while controlling the arm so as not to hinder the displacement of other devices only during X-ray irradiation, and is retracted after the imaging.

Japanese Patent No. 3519248 Japanese Patent No. 3927348 Japanese Patent No. 4130680

However, the above-described technology has a problem that the particle beam therapy apparatus is complicated by the arm and the control mechanism thereof, and the treatment time is prolonged by an arrangement time and an evacuation time of the X-ray imaging apparatus.
On the other hand, it is necessary that the X-ray image acquired by X-ray imaging is clear enough to accurately specify the position of the affected part.

  The present invention has been made in view of such circumstances, and has been made in order to solve the above-described problems. A particle beam therapy apparatus capable of acquiring a high-quality X-ray image with a simple configuration and having a short treatment time, an operation method thereof, and It is intended to provide a moving plate.

  The particle beam therapy system according to the present embodiment includes a particle beam irradiator that emits a particle beam, a rotating gantry that supports the particle beam irradiator, and a plurality of moving plates along a circumferential direction of the rotating gantry. A moving floor that forms a horizontal portion below the top plate on which the irradiation target is placed, an X-ray generator that generates X-rays, and an X-ray that detects the X-rays that pass through and reach the moving floor. A first floor member through which the X-ray is detectably transmitted by the X-ray detector; and an X-ray transmittance smaller than the first floor member. A second floor member, wherein the first floor member and the second floor member are made of the same material, and the thickness of the first floor member is smaller than the thickness of the second floor member.

  The particle beam therapy system according to the present embodiment includes a particle beam irradiator that emits a particle beam, a rotating gantry that supports the particle beam irradiator, and a plurality of moving plates along a circumferential direction of the rotating gantry. A moving floor that forms a horizontal portion below the top plate on which the irradiation target is placed, an X-ray generator that generates X-rays, and an X-ray that detects the X-rays that pass through and reach the moving floor. A first floor member through which the X-ray is detectably transmitted by the X-ray detector; and an X-ray transmittance smaller than the first floor member. A second floor member, and has a region whose cross section orthogonal to the rotation axis of the rotating gantry is constituted only by the first floor member.

  The operation method of the particle beam therapy system according to the present embodiment is configured such that the position of the first floor member that transmits X-rays on the X-ray irradiation area generated by the X-ray generator at the angle of the rotating gantry that performs X-ray imaging is determined. Adjusting, detecting the X-rays transmitted through the first floor member with an X-ray detector, and adjusting the position of the irradiation target based on the acquired X-ray image; Irradiating the irradiation target with a particle beam when the position is appropriate.

  The moving plate according to the present embodiment includes a plurality of moving plates that form a moving floor that rotates along a rotating direction of a rotating gantry of the particle beam therapy device, wherein at least one of the moving plates is configured to emit the X-rays. A first floor member that is detectably transmitted by an X-ray detector, and a second floor member that has a lower X-ray transmittance than the first floor member, wherein the first floor member and the second floor member are The first floor member is made of the same material, and the thickness of the first floor member is smaller than the thickness of the second floor member.

  According to the present invention, there is provided a particle beam therapy apparatus capable of acquiring high-quality X-ray images with a simple configuration and having a short treatment time, an operation method thereof, and a moving plate.

1 is a schematic configuration diagram of a particle beam therapy system according to an embodiment. FIG. 2 is a diagram illustrating an example of the particle beam therapy apparatus according to the first embodiment, which uses an all-round gantry. (A) is a particle beam therapy system according to the first embodiment, which is a cross-sectional view along a central axis of a rotating gantry, and (B) is a particle beam therapy system according to the first embodiment, which is a central axis of the rotating gantry. Sectional view of the particle beam therapy system in a direction perpendicular to FIG. The perspective view which shows an example of the moving floor provided in the support guide. The top view which shows the modification of a moving floor and is a horizontal slide type. (A) is a perspective view showing an example of a moving plate of the particle beam therapy system according to the first embodiment, and (B) is an explanatory diagram when the moving plate shown in (A) is irradiated with X-rays. The schematic block diagram of the particle beam therapy apparatus concerning 2nd Embodiment. The schematic block diagram of the treatment space of a partial rotation gantry. (A) is a particle beam therapy system according to the third embodiment, which is a cross-sectional view along a central axis of a rotating gantry, and (B) is a particle beam therapy system according to the third embodiment, which is a central axis of the rotating gantry. Sectional drawing of the particle beam therapy system cut | disconnected in the direction perpendicular | vertical to FIG. FIG. 13 is a schematic cross-sectional view of a moving sheet provided in the particle beam therapy system according to the third embodiment. (A) is a perspective view of a moving plate provided in the particle beam therapy system according to the fourth embodiment, (B) is a cross-sectional view of the II section shown in (A), and (C) is shown in (A). Sectional drawing of the II-II section. 9 is a flowchart illustrating an operation procedure of the particle beam therapy system according to the third embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram of a particle beam therapy system 10 (hereinafter, simply referred to as “the therapy system 10”) according to the embodiment.
Charged particles such as protons or carbon ions emitted from the ion source 11 become a particle beam B (particle beam B) accelerated by the particle beam accelerator 12.

The particle beam B is guided to the treatment building 14 where the patient 13 of the irradiation target is located using the magnetic field.
Further, the particle beam B is guided to the particle beam irradiation device 16 connected to the accelerator 12 via the rotary joint 20.
Then, the particle beam B is emitted from the distal end of the particle beam irradiator 16 toward the affected part 19 of the patient 13 fixed to the top plate 18.

The particle beam irradiator 16 is supported by the rotating gantry 21 in order to maintain the attitude of the particle beam irradiator 16 that changes the irradiation angle in various ways.
The rotating gantry 21 is a rotating structure provided as a support for the particle beam irradiation device 16.
When the rotating gantry 21 makes a displacement such as rotation with respect to the treatment building 14, the particle beam irradiation device 16 can be displaced into various postures.

Further, the top plate 18 arranged on the treatment table fixed to the foundation 22 constructed in the treatment building 14 can also change its posture within a range where an excessive load is not applied to the patient 13.
Since the patient 13 or the technician 38 (FIG. 2B) or the like accesses the periphery of the table 18, a floor surface that maintains the horizontal position regardless of the displacement of the rotating gantry 21 is arranged below the table 18. You.
If the portion of the floor surface arranged on the passage trajectory of the particle beam irradiation device 16 does not displace, the displacement of the particle beam irradiation device 16 is hindered.

Therefore, at least the floor surface on this passage trajectory needs to be a movable floor 24 that retreats from the occupied range 23 (FIG. 5) of the particle beam irradiator 16 as the particle beam irradiator 16 passes.
The movable floor 24 slides by being fixed to the foundation 22 directly or via the floor surface, or by being slidably engaged with a support guide 26 a arranged in the rotating gantry 21.
Details of the moving floor 24 will be described later.

In the treatment apparatus 10, an X-ray generator 27a (27) installed toward the patient 13 and emitting X-rays, and an X-ray detector 27b (27) (Flat) for detecting X-rays transmitted through the patient 13 Panel Detector: FPD).
Hereinafter, the X-ray generator 27a and the FPD 27b are collectively referred to as an X-ray imaging device 27 as appropriate.
In order to clearly capture the periphery of the affected part 19 with X-rays, the X-ray imaging device 27 needs to be arranged on or near the passage trajectory of the particle beam irradiation device 16 at least at the time of X-ray imaging.

Therefore, in the treatment apparatus 10 according to the embodiment, the X-ray imaging apparatus 27 is fixed to the non-collision area 31, and the X-ray generator 27a and the FPD 27b are installed at positions facing each other with the moving floor 24 interposed therebetween.
The non-collision area 31 is an area where the X-ray imaging device 27 does not collide with any of the particle beam irradiation device 16, the rotating gantry 21, and the moving floor 24 without using an electronic position control mechanism.
Hereinafter, a specific example of the treatment apparatus 10 shown in FIGS. 2 to 12 will be described, including the description of the non-collision area 31.

[First Embodiment]
FIG. 2 is a diagram illustrating an example of the treatment apparatus 10 according to the first embodiment, which uses an all-round gantry 21a.
Although not shown, the particle beam irradiator 16 is provided with a large number of vacuum ducts, beam deflecting electromagnets, irradiation field forming electromagnets, various monitors, mounts, and other structures, and is very heavy.
Therefore, in order to stably support and displace the heavy particle beam irradiation machine 16, a cylindrical full-rotation gantry 21a (21) as shown in FIG. 2 is often used.

  Such an all-around rotating gantry 21a is mounted on, for example, a rotation drive unit 34 installed on the foundation 22, and rotates around the central axis (Z axis) of the cylinder by the rotation of the rotation drive unit 34.

The particle beam irradiator 16 is fixed to the treatment space 36 with the distal end of the particle beam irradiator 16 protruding.
By making the base 22 concave around the body of the full-rotation gantry 21a, the full-rotation gantry 21a rotates 360 degrees around the central axis without the outer projection of the particle beam irradiation device 16 colliding with the base 22. Can be rotated degrees.

FIG. 3A is a cross-sectional view of the treatment device 10 for the full-rotation gantry 21a shown in FIG. 2 along the central axis of the full-rotation gantry 21a.
FIG. 3B is a cross-sectional view of the treatment apparatus 10 in a direction perpendicular to the central axis.
FIG. 4 is a perspective view showing an example of the moving floor 24 provided on the support guide 26a.

(Arrangement of moving floor 24)
As shown in FIGS. 3A and 4, the movable floor 24 is formed by, for example, a group of elongated movable plates 37 arranged side by side along the support guide 26a.
The support guide 26a includes, for example, a horizontal portion that is horizontal below the top plate 18, and a curved portion that curves along the inner peripheral surface of the full-rotation gantry 21a and is connected to both ends of the horizontal portion. .

The two support guides 26 a having such a shape are engaged with both ends in the longitudinal direction of the movable plate 37 in a pair facing each other.
The moving plate 37 is slidable along the support guide 26a by being engaged with the support guide 26a via a roller (not shown) rotated by a motor or the like.
Then, the group of the moving plates 37 below the top plate 18 forms a horizontal envelope and becomes the moving floor 24.
In this specification, “sliding” means that the members that come into contact with each other move relatively to each other.
For example, sliding includes moving relatively with a roller or gear or sliding on a smooth surface that has come into contact.

The tip of the particle beam irradiation device 16 is inserted and fixed at a position between the pair of support guides 26a.
In other words, a part of the entire circumference of the support guide 26a has an area where the moving plate 37 does not exist, and the tip is inserted into this area.

When the particle beam irradiator 16 is rotated by the rotation of the full rotation gantry 21a, the moving plate 37 is pushed by the particle beam irradiator 16 and slides along the circling direction of the particle beam irradiator 16.
That is, the moving plate 37 is slid in the traveling direction of the particle beam irradiation device 16 to be retracted from the occupation range 23 (FIG. 5) of the particle beam irradiation device 16.

As shown in a top view of a modified example of the movable floor 24 in FIG. 5 showing a horizontal slide type, the retreat direction of the movable plate 37 is perpendicular to the circling direction of the particle beam irradiation device 16. There may be.
In the case of the horizontal slide type movable floor 24, for example, a plurality of linear support guides 26b are provided along the central axis of the all-around rotating gantry 21a.
Then, the sliding drive unit 35, which has detected the circumferential angle about the center axis of the rotating gantry 21 of the particle beam irradiation device 16 by the passage sensor 39, slides the shaft 41 connected to the moving plate 37 along the support guide 26 b. Move.

Here, the “circumferential angle” defines a position at which the particle beam irradiation device 16 stops vertically above as 0 degree, and refers to an angle rotated about the central axis of the rotating gantry 21 from this angle. The same applies to the following.
The moving floor 24 is retracted from the occupied area 23 by the particle beam irradiation device 16 by being pulled by the shaft 41.

(Arrangement of X-ray equipment 27)
On the other hand, when the rotating gantry 21 is the full-circular gantry 21a, the X-ray generator 27a is fixed to, for example, the body of the full-circular gantry 21a.
By fixing the X-ray generator 27a to the full rotation gantry 21a, the X-ray generator 27a rotates together with the full rotation gantry 21a, so that the X-ray generator 27a does not collide with the particle beam irradiation device 16.
That is, the gap formed between the inner wall surface of the trunk of the full-rotation gantry 21 a and the inner peripheral surface of the trunk and the curved surface of the movable floor 24 is the non-collision area 31.
That is, this area is a non-collision area 31 where the X-ray generator 27a does not collide with the particle beam irradiation device 16 or the like without using an electronic position control mechanism.

In this case, if the FPD 27b is provided at the tip of the particle beam irradiation device 16, the relative angle between the FPD 27b and the X-ray generator 27a does not change, and the installation angle of the X-ray detection surface can be fixed.
The FPD 27b installed on the particle beam irradiation device 16 itself does not collide with the particle beam irradiation device 16 and does not hinder the displacement of the particle beam irradiation device 16.
That is, when the FPD 27b is fixed to the particle beam irradiation device 16, the vicinity of the tip of the particle beam irradiation device 16 is the non-collision area 31 within a range where the FPD 27b does not hinder the displacement of the particle beam irradiation device 16. .

In addition, a cover 17 that covers the projecting portion is provided on a projecting portion of the particle beam irradiator 16 projecting into the entire circumference rotating gantry 21a.
Even when the FPD 27b is provided on the inner surface or the outer surface of the cover 17, the FPD 27b does not hinder the displacement of the particle beam irradiation device 16 or the like.
Therefore, even when the FPD 27b is provided on the inner surface and the outer surface of the cover 17, the FPD 27b is provided in the non-collision area 31.

Note that the FPD 27b may be housed in the particle beam irradiator 16 or the cover 17, even when the installation angle can be fixed.
In addition, the fixed portion of the particle beam irradiation device 16 on the inner peripheral surface of the full-rotation gantry 21a may be projected and exposed to the treatment space 36 in some cases.
In this case, the FPD 27b may be installed in this exposed portion (not shown), and the vicinity of the exposed portion is also the non-collision area 31.

It is desirable that two sets of the X-ray imaging apparatuses 27 be installed at an angle of ± 45 degrees from the beam irradiation axis.
By acquiring X-ray images from two directions, the three-dimensional position of the affected part 19 can be grasped.

In addition, by installing in a horizontal direction and a vertical direction, it is possible to use an image processing method common to a conventional fixed irradiation room.
Further, the positions of the X-ray generator 27a and the FPD 27b are reversed, and the X-ray generator 27a is installed inside the treatment space 36 such as near the tip of the particle beam irradiation device 16, and the FPD 27b is installed on the full-rotation gantry 21a. May be.
Hereinafter, although not particularly specified, the positions of the X-ray generator 27a and the FPD 27b are interchangeable in all examples.

(Configuration of the moving plate 37)
As described above, when the X-ray generator 27a is installed on the entire rotating gantry 21a and the FPD 27b is installed on the particle beam irradiation device 16 or the like, the moving floor 24 is arranged between them.
That is, the X-rays emitted from the X-ray generator 27a by the movable floor 24 are shielded by the movable floor 24, and do not reach the FPD 27b on the opposite side of the movable floor 24 from the X-ray generator 27a.
Therefore, as shown in an example of the moving plate 37 in FIG. 6A, the moving plate 37 is configured by a first floor member 37a and a second floor member 37b (37) having different X-ray transmittances.

The second floor member 37b serving as a base material of the movable plate 37 is, for example, an aluminum alloy (for example, JISA5052) having a width of about 400 mm and a length of about 2000 mm, and has sufficient strength as a floor surface on which the patient 13 gets on and off.
On the other hand, the first floor member 37a (37) is made of a material having a higher X-ray transmittance than the second floor member 37b.
That is, the one in which the transmittance ratio η of the first floor member 37a to the second floor member 37b is larger than 1 is selected.

For example, carbon-fiber-reinforced plastic (CFRP) has high strength with respect to X-ray transmittance and is suitable as a material of the first floor member 37a.
It is known that the X-ray transmittance of CFRP is about five times that of aluminum having the same thickness.

The material of the first floor member 37a may be the same as that of the second floor member 37b.
Even if the first floor member 37a and the second floor member 37b are made of the same material, the X-ray transmittance can be increased by reducing the thickness of the first floor member 37a.

(Installation position of the first floor member 37a)
FIG. 6B is an explanatory diagram when the moving plate 37 shown in FIG. 6A is irradiated with X-rays.
The irradiation range of the X-ray emitted from the X-ray generator 27a has a certain width.
The patient 13 only needs to be irradiated with a minimum amount of X-rays capable of specifying a position such as a diseased part 19 or a marker embedded around the diseased part 19.
That is, some of the X-rays emitted from the X-ray generator 27a reach the patient 13, and are thereafter detected by the FPD 27b.

Therefore, as shown in FIG. 6B, the first floor member 37a is provided in a range of the moving plate 37 that includes the intersection plane 30 with the irradiation range (FIG. 6B).
The first floor member 37a is provided with a frame member 43, for example, as shown in FIG. 6B, and is coupled to the second floor member 37b via the frame member 43.
It is assumed that the frame member 43 is included in the second floor member 37b unless a material that allows X-rays to be transmitted is selected.

The term “coupled” as used herein naturally includes the case where the second floor member 37b is perforated and the first floor member 37a is fitted into the perforated portion.
If a screw or the like is used for coupling the first floor member 37a, the first floor member 37a can be easily removed, and the X-ray generator 27a can be checked without removing the entire moving plate 37.
In addition to the connection by the screw, adhesion by an adhesive or welding may be used, and the connection method is not limited.

Further, by making the size of the perforated portion one size larger than that of the X-ray generator 27a, the X-ray generator 27a can be easily taken in and out of the perforated portion.
Note that the moving plate 37 provided with the first floor member 37a often has lower strength than the moving plate 37 not provided with the first floor member 37a.
Therefore, it is desirable to provide the first floor member 37a only on the specific moving plate 37 which is the minimum.

For example, the two sets of X-ray imaging devices 27 are often fixed at an angle of ± 45 degrees from the irradiation axis of the particle beam irradiation device 16 for the above-described reason.
Therefore, in this case, the movable floor 24 provided with the first floor member 37a is also provided on the several movable plates 37 at an angle of ± 45 degrees from the irradiation axis and the periphery thereof.

As described above, according to the treatment apparatus 10 according to the first embodiment, a high-quality X-ray image can be acquired with a simple configuration.
Further, since it is not necessary to retreat the X-ray imaging device 27 as needed, the treatment time can be reduced.

[Second embodiment] (Partial rotation gantry 21b)
FIG. 7 is a schematic configuration diagram of a treatment apparatus 10 according to the second embodiment.
In recent years, as shown in FIG. 7, a partially rotating gantry 21b (21) using a rail track 40 or a part of a cylinder has been known.
In FIG. 7, various accompanying devices such as a balance weight that is connected to the particle beam irradiation device 16 and balances the weight with the particle beam irradiation device 16 are omitted.

In the partial rotation gantry 21b as shown in FIG. 7, two rail tracks 40 having a curved shape and an angle range smaller than 360 degrees are provided.
Then, the two rotation assisting bodies 25 are engaged with the two rail tracks 40.
The particle beam irradiator 16 is supported by the rotation assisting body 25 and rotates at an angle smaller than 360 degrees around the patient 13 fixed to the table 18.

When the partial rotation gantry 21b is used, the top plate 18 is horizontally rotated while the displacement angle of the particle beam irradiation device 16 is limited, so that the particle beam B is irradiated from an arbitrary angle as in the case of the full rotation gantry 21a. Becomes possible.
By limiting the displacement angle, a large non-collision area 31 can be secured near the top plate 18.
In the second embodiment, a case will be described in which the treatment apparatus 10 is applied to a partial rotation gantry 21b.

FIG. 8 is a schematic configuration diagram of the treatment space 36 of the partial rotation gantry 21b.
As shown in FIG. 8, the treatment apparatus 10 according to the second embodiment can enter and exit from the position of the trunk of the rotating gantry 21 in a direction perpendicular to the central axis, unlike the first embodiment.
Therefore, the top plate 18 is disposed at a position close to the base 22 even during the treatment.

Thus, for example, one of the two X-ray generators 27a is fixed to a portion such as the base 22 that does not displace even when the partially rotating gantry 21b rotates.
When the X-rays are emitted from the X-ray generator 27a fixed to the base 22, the X-rays emitted to the FPD 27b are radiated to the patient 13 without being shielded by the moving floor 24.
Therefore, with respect to the X-ray imaging apparatus 27 including the X-ray generator 27a fixed to the base 22, it is not necessary to devise the movable plate 37 as in the first embodiment.

However, as described above, in order to acquire the three-dimensional position coordinates of the affected part 19, the two X-ray generators 27a need to be set at an angle of, for example, 90 degrees.
Therefore, even in the case of the partial rotation gantry 21b, the remaining one of the two X-ray generators 27a is provided at a position facing the FPD 27b with the movable floor 24 interposed therebetween as in the first embodiment.

Therefore, similarly to the first embodiment, the first floor member 37a is provided on the movable plate 37 so that the remaining one set of the X-ray imaging devices 27 can also perform X-ray imaging.
Although not shown, the PDF that is paired with the X-ray generator 27a provided on the base 22 is provided at the tip of the particle beam irradiation device 16, for example.
Further, a PDF paired with the X-ray generator 27a provided on the partial rotation gantry 21b is provided on the base 22, for example.

  As described above, according to the second embodiment, even when the partial rotation gantry 21b is the partial rotation gantry 21b, the same effect as in the first embodiment can be obtained.

Note that the second embodiment has the same structure as the first embodiment except that the rotating gantry 21 is a partial rotating gantry 21b, and thus redundant description will be omitted.
Also in the drawings, parts having a common configuration or function are denoted by the same reference numerals, and redundant description will be omitted.

  Thus, the same effect as in the first embodiment can be obtained in the treatment apparatus 10 according to the second embodiment.

[Third Embodiment] (Correction of relative circumferential angle of first floor member 37a and particle beam irradiation device 16)
FIGS. 9A and 9B are schematic cross-sectional views showing a treatment apparatus 10 according to the third embodiment.
FIG. 9A is a cross-sectional view of the treatment device 10 for the full-rotation gantry 21a shown in FIG. 2 along the center axis of the full-rotation gantry 21a, similarly to FIG. 3A.
FIG. 9B is a cross-sectional view of the treatment apparatus 10 in a direction perpendicular to the center axis, similarly to FIG. 3B.

  As shown in FIG. 9, the treatment apparatus 10 according to the third embodiment includes, in addition to the configuration of the first embodiment, a sensor unit 44 that detects the position of the first floor member 37 a, and the first floor member 37 a And a position adjusting unit 46 that slides the movable plate 37 based on the position of the first floor member 37 a and arranges the first floor member 37 a on the irradiation area of the X-ray imaging apparatus 27.

When the X-ray generator 27a is installed on the full rotation gantry 21a, the X-ray generator 27a rotates in a substantially perfect circle around the central axis.
On the other hand, since the movable floor 24 moves along the support guide 26a, the movable floor 24 also forms a curved portion and a horizontal portion.

In this horizontal part, the length of the movable floor 24 with respect to the central angle of rotation is shorter than that of the curved part.
Therefore, when the entire circumference rotating gantry 21a and the moving plate 37 rotate at the same angular velocity, the circumferential angle of the particle beam irradiation device 16 and the circumferential angle of the moving plate 37 are shifted.
That is, the first floor member 37a having a 45 ° circumferential angle difference at a certain circumferential angle may be shifted from the irradiation area of the X-ray generator 27a at another circumferential angle.

If the positional relationship between the first floor member 37a and the X-ray generator 27a is shifted, the field of view of the X-ray image may be narrowed, or the X-ray may be blocked and the X-ray image may not be acquired.
When the circumferential angle difference of the particle beam irradiator 16 increases, this shift becomes remarkable.

Therefore, the first floor member 37a is usually provided on two or more adjacent moving plates 37 in consideration of the occurrence of such a shift in the horizontal portion.
However, also in the case where the first floor member 37a is provided on two or more adjacent moving plates 37, the frame member 43 blocks the X-ray, and it is not possible to appropriately specify the marker or the characteristic bone part. Sometimes.

Therefore, at least a part of the movable bed 24 is not connected to the particle beam irradiator 16 and has an allowance for sliding on the support guide 26 a independently of the particle beam irradiator 16. Is done.
Here, FIG. 10 is a schematic cross-sectional view of the moving sheet 47 provided in the treatment device 10 according to the third embodiment.

Specifically, for example, as shown in FIG. 10, the moving plates 37 are divided into groups every several sheets.
Adjacent moving plates 37 in the group are movably connected to each other with a space therebetween to form one moving sheet 47.
Then, the movable sheet 47 is engaged with the supporting guide 26a so that the position of the moving sheet 47 can be overlapped with the position of the adjacent moving sheet 47.

For example, the support guide 26a is provided with two lanes (not shown), an inner lane and an outer lane.
Then, the adjacent moving sheets 47 are alternately engaged with the inner lane and the outer lane.
Adjacent moving sheets 47 are slidably connected by a back roller 48 with adjacent ends overlapping so as to prevent generation of a gap.
As described above, the moving sheets 47 are engaged with an allowance for changing the distance between the centers of gravity, so that the peripheral angles of the particle beam irradiation device 16 and the first floor member 37a can be matched.

A part of the plurality of movable sheets 47 is fixedly connected to the body of the particle beam irradiation device 16.
The sensor unit 44 installed at a place where the base 22 does not displace, such as the base 22, detects the position of the first floor member 37a installed toward the mutually engaged moving sheet 47. When the X-ray generator 27a is fixed to the gantry 21a, the sensor unit 44 may be installed near the tip of the particle beam irradiation device 16.
As a detection method, for example, there is a method of attaching a fluorescent sticker to the frame member 43 and optically detecting the reflection of the fluorescent sticker.

  Also, without using the sensor unit 44, the relationship between the circumferential angle at which the particle beam irradiation device 16 stops and the circumferential angle of the first floor member 37a is stored in advance, and based on this relationship, the detected particle beam irradiation is performed. An angle correction amount corresponding to the peripheral angle at which the machine 16 has stopped may be obtained.

In any case, this information is sent to the position adjustment unit 46, and the position adjustment unit 46 corrects the information so that the first floor member 37a and the irradiation area of the X-ray generator 27a match.
In the calculation of the angle correction amount, it is preferable to calculate the gap so that the gap between the moving sheets 47 in the horizontal portion of the moving floor 24 is as small as possible.
This is because if the angle correction amount is larger than the margin of the overlapping end portion of the moving sheet 47, a gap is formed in the horizontal portion of the moving floor 24.

Further, it is desirable to provide a guard such as a roll screen at the end of the moving sheet 47 in the horizontal portion to prevent small articles from falling or being pinched when a gap is formed. Further, it is desirable to drive each moving sheet 47 so that a gap is not generated in a horizontal portion as much as possible.
The position adjusting section 46 slides the moving sheet 47 based on the relative circumferential angle between the first embodiment and the X-ray generator 27a, and arranges the first floor member 37a on the irradiation area.

  As described above, since the X-ray generator 27a and the first floor member 37a can be matched at any circumferential angle, X-ray imaging from any circumferential angle is possible.

Next, an operation procedure of the method of the treatment apparatus 10 according to the third embodiment will be described with reference to the flowchart of FIG. 12 (see FIG. 9 as appropriate).
First, by setting the peripheral angle of the particle beam irradiation device 16 to 45 degrees, the emission direction of X-rays is set to the horizontal direction and the vertical direction (S11).

Next, the position of the first floor member 37a is detected by the sensor unit 44, the circumferential angle of the first floor member 37a is adjusted to match the circumferential angle of the X-ray generator 27a (S12), and X-ray imaging is performed. (S13).
The X-rays pass through the first floor member 37a, pass through the vicinity of the affected part 19 of the patient 13, and are detected by the FPD 27b fixed to the particle beam irradiation device 16.
The position of the patient 13 is adjusted based on the acquired X-ray image so that the particle beam B can be accurately irradiated on the diseased part 19 set in the treatment plan (S14).

After adjusting the position of the patient 13, X-rays are taken again (S15).
The X-ray image acquired by the second imaging is confirmed, and the X-ray imaging and the position adjustment of the patient 13 are repeated until the position of the patient 13 becomes appropriate (S16: NO: S14).
Before and after positioning, the technician 38 may access the patient 13 on the movable floor 24 in order to check the posture and situation of the patient 13.
If the position of the patient 13 is appropriate, the positioning is completed (S16: YES).

Next, the particle beam irradiation device 16 is rotated and arranged at the emission position (S17).
The sensor unit 44 detects the position of the first floor member 37a, and slides the first floor member 37a so that the circumferential angle matches the circumferential angle of the X-ray generator 27a (S18).
In the case where the first floor member 37a cannot be completely matched with the peripheral angle of the X-ray generator 27a, the first floor member 37a may be included in the X-ray irradiation area.
When the respiration-synchronized irradiation is not performed, the particle beam irradiator 16 directly irradiates the particle beam B (S19: NO: S20).
After the irradiation with the predetermined dose according to the treatment plan, the irradiation ends (S21).
When irradiation is performed at another circumferential angle, the particle beam irradiator 16 is rotated and arranged at the next circumferential angle (S22: YES: S17).
After the irradiation at all the planned peripheral angles (S22: NO), the particle beam therapy is ended.

Further, as a particle beam therapy method, there is a respiration-synchronized irradiation method of irradiating the particle beam B in synchronization with the periodic displacement of the affected part 19 due to the respiration of the patient 13.
When the respiratory-gated irradiation method is performed, X-ray imaging is performed to confirm the position of the affected part 19 (S19: YES: S23).

Then, when the diseased part 19 comes to an optimum position, the particle beam B is irradiated at the same timing (S24).
X-ray imaging and particle beam B irradiation are performed until the irradiation ends (S25: NO: S23).
After the irradiation of the particle beam B at a specific circumferential angle is completed, the full-circle rotating gantry 21a is rotated to move the particle beam irradiator 16 to another circumferential angle in the same manner as in the normal irradiation therapy (S25: YES). : S22: YES: Go to S17).

In addition, since the circumferential angle of the first floor member 37a can be adjusted, X-ray photography can be performed many times at the stopped circumferential angle without returning the particle beam irradiation device 16 to the original 45 ° circumferential angle. Can be implemented.
Further, for example, even when the patient's physical condition deteriorates immediately before the beam irradiation, the patient leaves the room, and returns to the treatment table again, the first floor member is adjusted according to the circumferential angle of the particle beam irradiation device 16 stopped as described above. By adjusting the peripheral angle of 37a, it is possible to perform favorable X-ray photography without returning the peripheral angle of the particle beam irradiation device 16 to the initial angle (positioning angle).

Positioning can be confirmed and treatment can be resumed in a short time without the rotation of the particle beam irradiation machine 16 and the drive system of the X-ray device.
Although the full-rotation gantry 21a has been described, the third embodiment can be similarly applied to the partial rotation gantry 21b.

The third embodiment has the same structure and operation procedure as the first embodiment except that the moving floor 24 is divided into the moving sheets 47 and the circumferential angle at which the moving floor 24 is stopped is corrected.
Also in the drawings, parts having a common configuration or function are denoted by the same reference numerals, and redundant description will be omitted.

  As described above, according to the treatment apparatus 10 according to the third embodiment, in addition to the effects of the first embodiment, the circumferential angles of the X-ray generator 27a and the first floor member 37a are made to match from any circumferential angle. Therefore, X-ray imaging at an arbitrary circumferential angle becomes possible.

Further, it is not necessary to return the particle beam irradiator 16 to the circumferential angle (positioning angle) at the start of the treatment every time X-ray imaging is performed, so that the treatment time can be reduced.
Similarly, since there is no need to return to the circumferential angle (positioning angle) at the start of the treatment, respiratory-synchronous irradiation or moving object synchronized or tracked with the displacement of the affected part 19 due to the respiration of the patient 13 during irradiation of the particle beam or a slight change in the body position Tracking irradiation is also possible.
Further, since X-ray imaging can be performed from an arbitrary peripheral angle, X-ray irradiation can be performed from an optimal peripheral angle in relation to the affected part 19.

[Fourth embodiment]
FIG. 11A is a perspective view of a moving plate 37 of the treatment apparatus 10 according to the fourth embodiment.
FIG. 11B is a sectional view taken along the line II of FIG. 11A, that is, a sectional view of the second floor member 37b.
FIG. 11C is a cross-sectional view taken along the line II-II shown in FIG. 11A, that is, a cross-sectional view of the first floor member 37a.

As shown in FIG. 11A, the treatment apparatus 10 according to the fourth embodiment is configured such that the first floor member 37a provided on two or more moving plates 37 adjacent in the circumferential direction is different from the second floor member 37b. It is continuous without being pinched.
That is, the first floor member 37a is continuously arranged in the circumferential direction without including the frame member 43 (FIG. 6) shown in the first embodiment.

That is, the first floor member 37a is connected to the second floor member 37b divided into two along the circumferential direction.
In order to secure the rigidity of the first floor member 37a, a rib (not shown) is provided at a connecting portion between the first floor member 37a and the second floor member 37b to connect the first floor member 37a and the second floor member 37b. May be.

(Condition of transmission path length)
The first floor member 37a arranged continuously may have, for example, an L-shape or a U-shape according to the shape of the second floor member 37b.
However, when the X-rays penetrate the first floor member 37a having such a shape, when the incident point and the incident angle on the first floor member 37a continuously change, the transmission path length suddenly changes discontinuously.

  That is, when the first floor member 37a has a sharp shape such as a right angle, the transmission path length is discontinuous due to a continuous change in the relative angle between the first floor member 37a and the X-ray generator 27a. Will change suddenly.

Due to such a sudden change in the transmission path length, a sharp peak may be generated in the FPD 27b at which it is recognized that there is some kind of object.
Therefore, when the positional relationship between the first floor member 37a and the X-ray generator 27a changes, the transmission path length of the X-rays entering the first floor member 37a is formed not to change suddenly.
For example, as shown in FIG. 11 (C), it is desirable that each apex angle of the first floor member 37a be as smooth and gently curved as possible.

Further, the shape of the first floor member 37a is made as flat as possible so that the thickness does not change.
For example, as can be seen by comparing FIGS. 11B and 11C, it is desirable that the bent end of the first floor member 37a be as short as possible.

  Further, it is desirable that the X-ray generator 27a has a shape that does not exceed the length set as the allowable upper limit with respect to incidence of X-rays from any relative position that the first floor member 37a and the X-ray generator 27a can take. .

Note that the fourth embodiment has the same structure and operation procedure as the first embodiment except that the first floor member 37a is continuously arranged without providing the frame member 43 and the shape of the moving plate 37 is defined. Therefore, duplicate description will be omitted.
Also in the drawings, parts having a common configuration or function are denoted by the same reference numerals, and redundant description will be omitted.

  As described above, according to the treatment apparatus 10 according to the fourth embodiment, in addition to the effects of the third embodiment, the angle of the relative position between the X-ray generator 27a and the movable floor 24 by the sensor unit 44, the position adjustment unit 46, and the like. X-ray imaging can be performed without correction.

  According to the treatment apparatus 10, the particle beam therapy method, or the moving plate 37 of at least one embodiment described above, by providing the first floor member 37a on the moving plate 37, a high-quality X-ray image can be obtained with a simple configuration. And the treatment time can be shortened.

While some embodiments of the invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions.
These embodiments can be implemented in other various forms, and various omissions, replacements, changes, and combinations can be made without departing from the spirit of the invention.
These embodiments and modifications thereof 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 therapy apparatus (therapy apparatus), 11 ... Ion source, 12 ... Particle beam accelerator, 13 ... Patient (irradiation target), 14 ... Treatment building, 16 ... Particle beam irradiation machine (particle beam irradiation machine), 17 ... Cover, 18 ... Top plate, 19 ... Affected part, 21 ... Rotating gantry (support, rotating structure), 21a (21) ... Full-rotation gantry, 21b (21) ... Partial rotation gantry, 22 ... Basic, 23 ... Occupied range, 24 moving floor, 25 rotation assisting body, 26 (26a, 26b) support guide, 27 (27a, 27b) X-ray imaging equipment (X-ray generator, X-ray detector), 31 non- Collision area, 34: rotation drive unit, 35: slide drive unit, 36: internal space, 37 (37a, 37b): moving plate (first floor member, second floor member), 38: engineer, 39: passage sensor , 40 ... rail track 41 ... shaft, 43 ... frame material, 44 ... Sa unit, 46 ... position adjusting section, 47 ... moving sheet, 48 ... rear roller, 49 ... rib, B ... particle beam (particle beam), eta ... ratio of the transmittance.

The present invention in view of such circumstances, has been made in order to solve the above problems, to provide a short particle therapy equipment for treatment over time can be obtained a high-quality X-ray image with a simple configuration Aim.

The particle beam therapy system according to the present embodiment includes a particle beam irradiator that emits a particle beam, a rotating gantry that supports the particle beam irradiator, and a plurality of moving plates along a circumferential direction of the rotating gantry. A moving floor that forms a horizontal portion below the top plate on which the irradiation target is placed, an X-ray generator that generates X-rays, and an X-ray that detects the X-rays that pass through and reach the moving floor. A first floor member through which the X-ray is detectably transmitted by the X-ray detector; and an X-ray transmittance smaller than the first floor member. A second floor member; and a sensor unit for detecting a position of the first floor member .

The particle beam therapy system according to the present embodiment includes a particle beam irradiator that emits a particle beam, a rotating gantry that supports the particle beam irradiator, and a plurality of moving plates along a circumferential direction of the rotating gantry. A moving floor that forms a horizontal portion below the top plate on which the irradiation target is placed, an X-ray generator that generates X-rays, and an X-ray that detects the X-rays that pass through and reach the moving floor. A first floor member through which the X-ray is detectably transmitted by the X-ray detector; and an X-ray transmittance smaller than the first floor member. A second floor member, and the first floor member is placed on the X-ray irradiation area in accordance with an angle correction amount based on a relationship between a circumferential angle at which the particle beam irradiation device stops and a circumferential angle of the first floor member. And a position adjusting unit to be arranged.

A particle beam therapy system according to this embodiment includes a particle beam irradiation apparatus for emitting a particle beam, a rotating gantry for supporting the particle beam irradiation apparatus, composed of a plurality of mobile plate along the circumferential direction of the rotating gantry A moving floor that forms a horizontal portion below the top plate on which the irradiation target is placed, an X-ray generator that generates X-rays, and an X-ray that detects the X-rays that pass through and reach the moving floor. At least one of the movable plates has a first floor member that transmits the X-rays so that the X-ray detector can detect the X-rays, and a lower X-ray transmittance than the first floor member. comprises a second floor member, said rotary gas entry comprises said first bed member to the moving plate all in the same circumferential angle between the X-ray generator when stopping within the movable range.

The present invention, short particle beam therapy equipment for treatment time is provided with can be obtained a high-quality X-ray image with a simple configuration.

According to the treatment apparatus 10 of at least one embodiment described above, by providing the first floor member 37a on the movable plate 37, a high-quality X-ray image can be acquired with a simple configuration and the treatment time can be reduced. Becomes possible.

Claims (7)

A particle beam irradiator that emits a particle beam,
A rotating gantry supporting the particle beam irradiation machine,
A moving floor that is formed of a plurality of moving plates along the rotating direction of the rotating gantry and forms a horizontal portion below a top plate on which the irradiation target is placed,
An X-ray generator for generating X-rays,
An X-ray detector that detects the X-rays that reach through the moving floor,
At least one of the moving plates is
A first floor member through which the X-rays are detectably transmitted by the X-ray detector;
A second floor member having a low line transmittance;
A particle beam therapy system comprising a sensor unit for detecting a position of the first floor member. A particle beam irradiator that emits a particle beam,
A rotating gantry supporting the particle beam irradiation machine,
A moving floor that is formed of a plurality of moving plates along the rotating direction of the rotating gantry and forms a horizontal portion below a top plate on which the irradiation target is placed,
An X-ray generator for generating X-rays,
An X-ray detector that detects the X-rays that reach through the moving floor,
At least one of the moving plates is
A first floor member through which the X-rays are detectably transmitted by the X-ray detector;
A second floor member having a low line transmittance;
A position adjusting unit that arranges the first floor member on the X-ray irradiation area according to an angle correction amount based on a relationship between a peripheral angle at which the particle beam irradiation device stops and a peripheral angle of the first floor member. A particle beam therapy system comprising: A particle beam irradiator that emits a particle beam,
A rotating gantry supporting the particle beam irradiation machine,
A moving floor that is formed of a plurality of moving plates along the rotating direction of the rotating gantry and forms a horizontal portion below a top plate on which the irradiation target is placed,
An X-ray generator for generating X-rays,
An X-ray detector that detects the X-rays that reach through the moving floor,
At least one of the moving plates is
A first floor member through which the X-rays are detectably transmitted by the X-ray detector;
A second floor member having a low line transmittance;
The particle beam therapy system, wherein the first floor member is provided on all of the movable plates at the same circumferential angle as the X-ray generator when the rotating gantry stops within a movable range. The particle beam therapy system according to any one of claims 1 to 3, wherein the first floor member is configured to be detachable from the moving floor. The particle beam therapy system according to claim 4, wherein an opening formed by removing the first floor member is larger than the X-ray generator. The particle beam therapy apparatus according to any one of claims 1 to 5, wherein at least one of the moving plates has the same width in the circumferential direction as the first floor member. The particle beam therapy system according to any one of claims 1 to 6, wherein the first floor member has the same width in the circumferential direction as the adjacent movable floor.

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