JP7023735B2 - How to control the particle beam therapy device and the particle beam therapy device - Google Patents

Description

An embodiment of the present invention relates to a particle beam therapy device and a method for controlling a particle beam therapy device that irradiates an affected portion of a patient with a charged particle beam to treat the patient.

A particle beam therapy technique is widely known in which an irradiation target center (isocenter) is set on an affected area of a patient such as cancer and an ion beam (charged particle beam) such as a proton or carbon ion is irradiated.

For example, the particle beam therapy device used for this treatment includes an ion beam generator, a beam transport system, and an irradiation device installed in a rotating gantry.

The ion beam accelerated by the ion beam generator reaches the irradiation device via the beam transport system, and is irradiated from the irradiation device to the affected part of the patient. At this time, the irradiation device can rotate around the patient with the rotation of the rotating gantry, and can irradiate the affected area with an ion beam based on the irradiation angle defined in the treatment plan. In order to reduce the damage to normal tissues in the vicinity of the affected area due to this ion beam, it is necessary to accurately irradiate the affected area with the ion beam. For this purpose, it is important to accurately position the particle beam irradiation unit and accurately align the patient's affected area with respect to the particle beam irradiation unit.

In general, it is known that the rotary gantry moves in a direction parallel to the axis of rotation with rotation, which is one of the factors for deteriorating the three-dimensional swing accuracy of the irradiation position.

Japanese Unexamined Patent Publication No. 2014-1134919 Japanese Unexamined Patent Publication No. 2016-031553

In the above-mentioned rotary gantry of the prior art, if the behavior parallel to the rotation axis is not sufficiently suppressed, the three-dimensional swing accuracy (irradiation target center accuracy) of the irradiation position when irradiating the irradiation target center from the irradiation device will rotate. With the rotation of the gantry, there was a possibility of variation of about several mm. As a result, there is a problem that it takes a lot of time to position the patient depending on the irradiation angle at the time of therapeutic irradiation.

An object of the present invention is to provide a particle beam therapy device and a control method for the particle beam therapy device capable of increasing the accuracy of the irradiation target center.

In order to achieve the above object, the particle beam therapy device according to the present embodiment is a particle beam therapy device having a rotating gantry that orbits an irradiation port for irradiating a charged particle beam to an internal radiotherapy chamber. It has a gantry body constituting a rotating gantry and a position measuring mechanism for measuring the relative position between the irradiation port provided on the gantry body and the treatment table on which the patient is placed, and at least one freedom measured by this measuring mechanism. It is characterized by having a movement control unit for moving and controlling the position of the treatment table in a direction of reducing the displacement of a degree or more.

Further, the control method of the particle beam therapy apparatus according to the present embodiment has a rotating gantry that orbits an irradiation port for irradiating a charged particle beam in a radiation therapy chamber provided inside, and the gantry constituting this rotating gantry. In the control method of the particle beam therapy device having the body, the irradiation port provided on the gantry body, and the treatment table on which the patient is placed, the relative position between the irradiation port and the treatment table is measured by a position measuring mechanism. It is characterized in that the position of the treatment table is moved and controlled in a direction of reducing the displacement of at least one degree of freedom measured by the position measuring mechanism.

An embodiment of the present invention can provide a particle beam therapy device and a control method for a particle beam therapy device capable of increasing the accuracy of the irradiation target center.

The perspective view which shows the embodiment of the particle beam therapy apparatus and the control method of the particle beam therapy apparatus which concerns on this invention. FIG. 3 is a schematic vertical sectional view taken along the rotation axis AA axis direction of the rotation gantry shown in FIG. 1. FIG. 3 is an enlarged vertical sectional view of a main part showing an embodiment of the particle beam therapy apparatus shown in FIG. 1. The enlarged vertical sectional view of the main part which shows the 2nd Embodiment of the particle beam therapy apparatus which concerns on this invention.

(First Example)
Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 shows a perspective view of the particle beam therapy device 14, and FIG. 2 shows a schematic vertical cross-sectional view of the rotary gantry 11 shown in FIG. 1 cut in the rotation axis AA axis direction.

In FIG. 1, the particle beam therapy device 14 orbits an irradiation port 4 for irradiating a radiotherapy chamber 15 with a charged particle beam (heavy particle beam, proton beam, etc.) and irradiates an accelerated particle beam from an arbitrary position. The radiotherapy chamber 15 is provided with a movement control unit 17 that moves the treatment table 5 and sets its position and direction, and an arm 6 whose base end is supported on the side of the irradiation port 4.

The particle beam therapy device 14 includes a main body (gantry body) 1, a mounting magnet (deflection magnet) 2, a magnet support 3, an irradiation port 4, a treatment table 5, an end ring 8, a counterweight 9, and a turning roller 10. have.

The main body 1 has a radiation therapy chamber 15 inside, accommodates an irradiation port 4, and has a mounting magnet 2, a magnet support 3, and a counterweight 9 including a deflection magnet installed outside. Further, the end ring 8 connected to the main body body 1 rotates in contact with the turning roller 10 installed on the gantry 12, and the charged particle beam is transferred from an arbitrary angle position to the patient 13 on the treatment table 5 (see FIG. 3). It is configured to be irradiated to.

The mounted magnet (deflection magnet) 2 is connected to the main body body 1 by a magnet support 3, and has a function of guiding charged particle beams to the irradiation port 4.

The counterweight 9 is a weight arranged on the opposite side in the target position, that is, in the rotation axis direction as the rotation axis (AA axis) direction of the mounting magnet 2 in order to maintain the weight balance of the main body 1 as a rotating body.

As shown in the schematic vertical sectional view taken along the rotation axis of the rotation gantry 11 in FIG. 2, it is known that the rotation gantry 11 moves in parallel with the rotation axes AA as the rotation gantry 11 rotates.

As shown in the vertical cross-sectional view of the radiation therapy chamber 15 cut in the rotation axis direction of the rotation gantry 11 of FIG. 3, one or more laser displacement meters 7 and one or more depending on the degree of freedom and location where the target 16 is measured. It is provided in the irradiation port 4 and the treatment table 5.

The laser displacement meter 7 measures the relative displacement of the irradiation port 4 and the treatment table 5 by one degree of freedom or more by the laser 18 to be transmitted and received, and the movement control unit 17 deviates from the irradiation target based on the measured relative displacement. The position of the treatment table 5 is feedback-controlled in the direction of reduction. Further, in the direction of reducing the deviation from the irradiation target, the irradiation direction of the charged particle beam irradiated from the irradiation port 4 by the deflection magnet 2 is feedback-controlled for each rotation angle of the rotating gantry 11 based on the relative position. Alternatively, both the position of the treatment table 5 and the irradiation direction of the charged particle beam may be feedback-controlled.

Further, when the relative position between the irradiation port 4 and the treatment table 5 on which the patient is placed exceeds a predetermined limit value, the movement control unit 17 transmits an abnormality signal and the operator confirms the abnormality by a speaker or the like. You may be able to do it.

Therefore, according to the present embodiment, the relative displacement of the irradiation port 4 and the treatment table 5 having one or more degrees of freedom is obtained by the laser displacement meter 7, and the measured displacement of one degree of freedom or more is reduced by the movement control unit 17. Since the position of the treatment table 5 and / or the charged particle beam irradiated from the irradiation port 4 is moved and controlled in the direction, the accuracy of the center of the irradiation target can be improved.

(Second Example)
Hereinafter, a second embodiment of the present invention will be described with reference to the accompanying drawings. Since the configurations of FIGS. 1 and 2 are the same, the description of the configuration is omitted, and the description will be described below with reference to FIG. In FIG. 4, the same parts as those in FIG. 3 are designated by the same reference numerals, and the description of the configuration of the parts will be omitted.

FIG. 4 is an enlarged vertical cross-sectional view of a main part of the radiotherapy chamber 15 obtained by cutting the second embodiment of the present invention in the rotation axis direction of the rotation gantry 11.

As shown in FIG. 4, a laser 18 irradiated from a laser transmitter 19 installed in a fixed portion such as a wall or a treatment room is applied to an irradiation port 4 or a treatment table 5 according to the degree of freedom and location to be measured. Light is received by one or a plurality of targets 16, and the relative displacement of the irradiation port 4 and the treatment table 5 is measured from the measurement positions of the laser transmitter 19 and the target 16 by one or more degrees of freedom. Then, based on the measured relative displacement, the movement control unit 17 feedback-controls the position of the particle beam and / or the treatment table 5 irradiated from the irradiation port 4 in the direction of reducing the deviation from the irradiation target.

Therefore, according to the present embodiment, the relative displacement of the irradiation port 4 and the treatment table 5 is measured from the measurement positions of the laser transmitter 19 and the target 16 to one degree of freedom or more, and the movement control unit 17 measures the measured one freedom. Since the position of the treatment table 5 and / or the charged particle beam irradiated from the irradiation port 4 is moved and controlled in the direction of reducing the displacement of a degree or more, the accuracy of the irradiation target center can be improved.

Although some embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention.

These embodiments can be implemented in various other embodiments, and various omissions, replacements, changes, and combinations can be made without departing from the gist of the invention.

These embodiments and variations thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

1 ... Body body (gantry body), 2 ... Mounted magnet (deflection magnet), 3 ... Magnet support, 4 ... Irradiation port, 5 ... Treatment table, 6 ... Arm, 7 ... Laser displacement meter, 8 ... End ring, 9 ... Counterweight, 10 ... Turning roller, 11 ... Rotating gantry, 12 ... Stand, 13 ... Patient, 14 ... Particle therapy device, 15 ... Radiation therapy room, 16 ... Target, 17 ... Movement control unit, 18 ... Laser, 19 ... laser transmitter, A ... axis of rotation.

Claims (6)

In a particle beam therapy device having a rotating gantry that orbits an irradiation port that irradiates a charged particle beam into a radiation therapy room provided inside.
The gantry body that makes up this rotating gantry and
It has a position measurement mechanism that measures the relative position between the irradiation port provided on the gantry body and the treatment table on which the patient rests, and the displacement in the direction of reducing the displacement of at least one degree of freedom measured by this measurement mechanism. A particle beam therapy device characterized by having a movement control unit that moves and controls the position of a treatment table. The particle beam therapy apparatus according to claim 1, wherein the position measuring mechanism arranges a laser displacement meter and a target on the irradiation port or the treatment table. The particle beam therapy apparatus according to claim 1, wherein the position measuring mechanism is provided with a laser displacement meter in the radiotherapy room or a wall, and a target is arranged in the irradiation port and / or the treatment table. The movement control unit has an additional configuration in which the irradiation direction of charged particle beams is feedback-controlled by a deflection magnet installed on the gantry body for each rotation angle of the rotating gantry based on the relative positions of the irradiation port and the treatment table. The particle beam therapy apparatus according to any one of claims 1 to 3, wherein the particle beam therapy apparatus is used. One of claims 1 to 4, wherein the movement control unit emits an abnormal signal when the relative position of the irradiation device and the treatment table on which the patient is placed exceeds a predetermined limit value. The particle beam therapy device according to. It has a rotating gantry that orbits the irradiation port that irradiates the charged particle beam in the radiation therapy room provided inside.
The gantry body that makes up this rotating gantry and
In the control method of the particle beam therapy device having the irradiation port provided on the body of the gantry and the treatment table on which the patient is placed.
The relative position between the irradiation port and the treatment table is measured by a position measuring mechanism, and the position is measured.
A control method for a particle beam therapy apparatus, which comprises moving and controlling the position of the treatment table in a direction of reducing a displacement of at least one degree of freedom measured by the position measurement mechanism.

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