JP6858027B2 - Treatment table - Google Patents

Description

The present invention relates to a treatment table and is particularly suitable for a radiation therapy device having a rotating gantry capable of irradiating a beam around a patient at any angle.

In the treatment of cancer by radiation, particle beams (for example, proton beams) that can be treated without relatively damaging normal cells have been attracting attention in recent years.

In order to irradiate the patient with a beam at an arbitrary angle, a rotating gantry capable of rotating the beam irradiation port (irradiation nozzle) by 360 ° is used in the particle beam therapy device.

A reference point for beam irradiation, called an isocenter, is located on the central axis of the rotating gantry, in front of the irradiation nozzle.

The treatment table on which the patient is placed is placed in the opening of the rotating gantry and holds the patient in a cantilever support for treatment with the isocenter.
An example of a radiotherapy treatment table using this particle beam is described in Patent Document 1. The treatment table for radiotherapy rotates around the vertical axis on a total of three axes, the Z axis in the vertical direction, the Y axis parallel to the gantry rotation axis, and the X axis orthogonal to the Z and Y axes. It is composed of a rotating axis (hereinafter referred to as θ axis).

Further, a robot arm type treatment table is described in Patent Documents 2 to 5.

Japanese Unexamined Patent Publication No. 11-313900 Japanese Patent No. 4948415 Japanese Unexamined Patent Publication No. 2016-116805 U.S. Pat. No. 8,745,789 U.S. Pat. No. 9,199372

The radiotherapy treatment table has a problem that the top plate can be lowered when getting on and off so that even a patient using a wheelchair can get on and off without any inconvenience.

In the treatment table described in Patent Document 1, since the thickness of the first arm is between the floor and the top plate, the "top plate height" cannot be lowered.

Further, in the treatment table described in Patent Document 2, the top plate can be lowered by providing a total of two or more axes that rotate in the vertical direction near the base of the robot arm in addition to the wrist portion. However, since the heavy top plate on which the patient gets on and off is supported at the tip of the robot arm like a cantilever, it is difficult to improve the positioning accuracy required for radiotherapy when the number of axes driven by vertical rotation increases. ..

Further, in the treatment table described in Patent Document 3, the top plate can be lowered by allowing the first arm to be stored under the floor, but there is a problem that the structure of the floor surface becomes complicated.

In order to solve the above problems, for example, the configuration described in the claims is adopted.
The present invention includes a plurality of means for solving the above problems, and to give an example thereof, a top plate, a second arm for supporting the top plate, and a first arm for supporting the second arm. The arm is provided with a swivel mechanism capable of swiveling the second arm with respect to the first arm, and the mounting portions of the first arm and the second arm are inclined. To do.

According to the treatment table of the present embodiment, at least one of the effects of high positioning accuracy, low top plate height for patient loading, and wide positioning movable range can be achieved without using a complicated structure. Can be done.

Schematic diagram of particle beam irradiation device Schematic diagram of the treatment table of the first embodiment Positioning transition diagram of treatment table 101 Positioning transition diagram of treatment table 102 Isotric rotation motion transition diagram of the treatment table of the first embodiment Schematic diagram of the treatment table of the second embodiment

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

The particle beam irradiation device will be described with reference to FIG. FIG. 1 (a) is a view seen from the gantry rotation axis direction, and FIG. 1 (b) is a view seen from the horizontal horizontal direction.

The particle beam irradiation device 1 is equipped with an accelerator (not shown) that generates a charged particle beam, a transport system 2, an irradiation nozzle 3 that is a charged particle beam irradiation port, and an irradiation nozzle 3 and 360 around the patient. ° A rotating gantry 4 that can rotate is provided. The rotating gantry 4 is loaded with an electromagnet 41 for bending a charged particle beam, which is obtained by accelerating charged particles generated by an ion source (not shown) with an accelerator (not shown) such as a synchrotron. The irradiation nozzle 3 can form the carried beam into a shape (shape of the affected part) necessary for treatment. The rotating gantry 4 can move the irradiation nozzle 3 around the patient 5 at any angle of 360 °. Patient 5 is placed on a top plate 61 on the treatment table 6. The treatment table 6 can be moved so that the affected part of the patient 5 is at the isocenter 9 position.

Further, there is a treatment table control device 81 connected to and controlled by the treatment table 6 and a rotation gantry control device 82 connected to and controlled by the rotation gantry 4, and overall control connected to the treatment table control device 81 and the rotation gantry control device 82. The device 83 is provided.

The treatment table of this embodiment will be described with reference to FIG.

The drive unit of the treatment table 6 includes a Z-axis drive mechanism 71, a first arm swivel mechanism 72, a second arm swivel mechanism 73, and a pitch roll yaw rotation mechanism 74 of the robot wrist portion in this order from the bottom.
The Z-axis drive mechanism 71 is a drive shaft that enables the support column 64 (a part of the Z-axis drive mechanism 71) to move in the direction of gravity. It consists of a linear drive mechanism using a linear guide and a ball screw. The first arm swivel mechanism 72 and the second arm swivel mechanism 73 are rotation mechanisms using a speed reducer with less backlash.

The first arm 63 turns horizontally with respect to the support column 64. The attachment portion of the second arm 62 is inclined and attached at the tip portion of the first arm 63. That is, the first arm 63 and the second arm 62 are inclined with respect to the floor surface. Specifically, the first arm 63 has a tapered shape. The mounting surface of the first arm 63 is inclined with respect to the horizontal plane, and the second arm 62 connected to the mounting surface is parallel to the upper surface of the first arm 63 and is inclined with respect to the floor surface. It is connected to the arm 63. Further, to explain from another side, the axis of the second arm swivel mechanism 73 connecting the first arm 63 and the second arm 62 is inclined from the direction perpendicular to the floor surface.

The amount of inclination (angle) is determined so that the gap between the tip of the second arm (top plate support portion) and the floor becomes small while the first arm 63 and the second arm 62 are arranged straight. Specifically, the lowest point of the second arm 62 is inclined so as to be smaller than the thickness of the first arm 63.

FIG. 2A shows a state in which the lower surface of the first arm 63 is close to the floor surface with the support column 64 lowered, and the tip of the second arm 62 is close to the floor surface, so that the height of the top plate is the lowest. It is a figure when it is set.

2 (a), (b) and (c) show a structural comparison between the treatment table 6 of the present embodiment and the treatment table 101 and the treatment table 102 having other structures.

The treatment table 101 has a structure in which the first arm is mounted on the Z-axis drive mechanism and the second arm is mounted on the first arm. The first arm and the second arm are mounted horizontally, and due to the thickness of the first arm, the wrist portion cannot be set as low as the floor surface.

The treatment table 102 has a structure in which the first arm is mounted on the Z-axis drive mechanism, but the second arm is mounted below the first arm. Since the first arm is arranged above the second arm, the wrist portion can be set as low as the floor surface as compared with the treatment table 101.

3 and 4 show positioning transition diagrams of the treatment table 101 and the treatment table 102, respectively.

Since the second arm is arranged on the first arm, the treatment table 101 does not interfere with each other and can be positioned anywhere within the horizontal plane as long as the arms can reach.

On the other hand, in the treatment table 102, the second arm, the top plate, the wrist portion, and the like interfere with the Z-axis drive device, and there is a limitation in positioning in the horizontal plane.

In the medical particle beam irradiator, the treatment table is required to rotate around the isocenter 9 according to the treatment plan. The operation method of rotating around the isocenter 9 while fixing the affected part to be irradiated at the same point on the coordinates is called isocentric rotation. FIG. 5 shows an example of an isocentric rotation operation of the treatment table 6 in the present embodiment. 5 (a) to 5 (e) are views of the treatment table 6 viewed from above, and FIGS. 5 (f) to 5 (j) are views of the treatment table 6 viewed from the horizontal direction.

In the treatment table 6 of the present embodiment, since the connection portion between the first arm 63 and the second arm 62 is always inclined, the first arm 63 and the second arm 63 are controlled by the treatment table control device 81 during the isocentric rotation. The Z-axis drive mechanism 71 and the pitch roll yaw rotation mechanism 74 of the top plate support portion are interlocked and driven according to the positioning posture of the two arms 62. Specifically, when controlling the tip of the second arm 62 or the base of the top plate to approach the base of the first arm 63 or the support column 64, the support column 64 is lowered by the Z-axis drive mechanism 71 at the same time. Control. On the contrary, when the tip of the second arm 62 or the base of the top plate is controlled to be separated from the base of the first arm 63 or the support column 64, the support column 64 is controlled to be raised by the Z-axis drive mechanism 71 at the same time. .. As a result, the height of the top plate is controlled to be kept constant. When the amount of inclination is not so large, the amount of movement of the Z-axis drive mechanism is also small, and when the amount of inclination is about 6 degrees as shown in FIG. 5, the amount of interlocking movement in the Z-axis direction is small.

In the treatment table of the present invention, the height of the top plate can be lowered to the lowest position when the first arm and the second arm are arranged straight (the state of FIG. 2A). The user positions and uses the arm in this state in the case of a patient who must bring the top plate height to the lowest position. On the other hand, when positioning at the treatment position (when positioning at the isocenter), the top plate can be positioned at an arbitrary position and height as shown in FIG.

The treatment table 6 of the present embodiment does not have a vertical rotation drive unit at the connection portion between the arms, and more preferably does not have a vertical rotation drive unit between the robot arm base portion and the inclined portion. More preferably, by not having a vertically rotating drive unit other than the wrist portion of the robot arm, it is resistant to the load at the tip of the robot arm and the positioning accuracy can be improved.

According to the treatment table of the present embodiment, the user can use the positioning of the patient loading and the positioning used for the treatment properly in the same structure, which was not possible with the treatment tables 101 and 102, (1) low for patient loading. The height of the top plate and (2) a wide positioning movable range can be achieved at the same time.

The treatment table of this embodiment is particularly suitable for radiotherapy applications that require high positioning accuracy and a wide range of motion, but is not limited thereto.

The description of the parts that overlap with the above-described embodiment will be omitted.

FIG. 6 shows a schematic diagram of the treatment table 103 of the present embodiment. The treatment table 103 of the present embodiment includes a support column 201 that moves in the Z-axis direction, a first arm 203, a second arm 205, a swivel mechanism 202 between the support column 201 and the first arm 203, and a first arm 203 and a first arm 203. It has a swivel mechanism 204 between the two arms 205.

In the treatment table 103 of the present embodiment, the swivel mechanism 202 that swivels the first arm 203 is tilted from the direction perpendicular to the floor surface, and the first arm 203 is tilted.

As a result, when the treatment table is lowered in the Z-axis direction for getting on and off the patient, the wrist portion, which is the tip of the second arm, can be brought close to the floor surface, and the top plate can be lowered.

1 Particle beam irradiation device 3 Irradiation nozzle 4 Rotating gantry 6 Treatment table 9 Isocenter 81 Treatment table control device

Claims (7)

Top plate and
A second arm that supports the top plate and
The first arm that supports the second arm and
A swivel mechanism having a swivel shaft capable of swiveling the second arm with respect to the first arm,
The Z-axis drive mechanism that supports the second arm and
Control device and
Have,
The mounting surface of the first arm is inclined with respect to the horizontal plane, and the second arm is connected to the first arm so as to be parallel to the upper surface of the first arm and inclined with respect to the floor surface. Being done
When the control device controls the tip of the first arm or the base of the top plate to approach the base of the second arm or the Z-axis drive mechanism during isocentric rotation, A treatment table characterized in that the Z-axis drive mechanism is controlled to be low. The treatment table according to claim 1.
A treatment table characterized in that the swivel axis is inclined with respect to a direction perpendicular to the floor surface. The treatment table according to claim 1.
A treatment table characterized in that the height of the lowest point of the second arm from the floor surface is smaller than the thickness of the first arm. The treatment table according to claim 1.
A treatment table characterized in that the second arm has a tapered shape such that the distance between the two side portions becomes smaller as the distance between the two sides approaches the tip. The treatment table according to claim 1.
A treatment table characterized in that the second arm is installed on the first arm. Top plate and
A second arm that supports the top plate and
The first arm that supports the second arm and
A Z-axis drive mechanism that supports the second arm and drives it in the Z-axis direction,
A rotation mechanism capable of rotating the top plate in a pitch roll yaw with respect to the first arm,
A first swivel mechanism capable of swiveling the second arm with respect to the first arm,
It has a second swivel mechanism that swivels the second arm with respect to the Z-axis drive mechanism.
The mounting surface of the first arm is inclined with respect to the horizontal plane, and the second arm is connected to the first arm so as to be parallel to the upper surface of the first arm and inclined with respect to the floor surface. A treatment table characterized by being done. The treatment table according to any one of claims 1 or 6.
Accelerator and
A radiation irradiation device having an irradiation nozzle.

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