JP3608079B2 - Radiation therapy gauge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiation therapy gauge having a structure capable of rotating a radiation irradiation apparatus to an optimal irradiation position of a patient, and particularly suitable for a radiation therapy apparatus having a rotating gantry that uses proton beams for medical use such as cancer treatment. Related to radiation therapy gauges.
[0002]
[Prior art]
Traditionally, X-rays, gamma rays, electron beams, and fast neutron rays have been used for cancer treatment as radiation medical treatment, but these radiations have the maximum radiation dose on the body surface before reaching the affected area. Therefore, the cancer treatment in the deep part of the body has a harmful effect such as damaging normal tissue near the body surface.
[0003]
On the other hand, proton therapy can maximize the radiation dose by targeting a cancer located at a certain depth in the body due to the nature of the proton beam obtained by accelerating to high energy using an accelerator. Normal tissues that transmit proton beams are less susceptible to wounds.
[0004]
In order to perform this proton beam treatment efficiently, it is necessary to accurately set a proton beam to the affected area of the patient, and the development of a radiotherapy apparatus having a structure capable of setting the radiation irradiation unit at the optimal irradiation position of the patient has been developed. It has been.
[0005]
In the above-mentioned radiotherapy apparatus, in order to perform radiotherapy from any direction around the patient, a rotating gantry apparatus capable of rotating 360 degrees around the patient and a radiotherapy gauge synchronized therewith are required. In particular, the safety of the radiation therapy gauge has been required to perform a comfortable treatment.
[0006]
As described in Japanese Patent Application Laid-Open No. 11-47287, a conventional radiation therapy gauge has a caterpillar structure in which the rotation path of the radiation irradiation apparatus is sandwiched between a fixed side and a moving side ring rail. .
[0007]
[Problems to be solved by the invention]
Since the conventional treatment gauge has a caterpillar forming the treatment gauge as an integral structure, a gap is generated in a part of the work space due to the rotation angle of the radiation irradiation apparatus. This is because the treatment gauge has a kamaboko-shaped cross-sectional shape, so that under the condition that the length of the caterpillar is constant, an insufficient length portion is generated depending on the rotation angle.
[0008]
To compensate for this, for example, an auxiliary work stand or fall prevention cover was attached, but the interval between the medical engineer and the patient is too large, and the medical engineer is working on the safety and workability of the medical practice for the patient. Was insufficient. Furthermore, there was a problem that the patient may be anxious about the treatment because of fear from high places.
[0009]
An object of the present invention is to solve the above-mentioned conventional problems, and does not depend on the rotational position of the radiation irradiation device, and always has a closed surface inside the radiation treatment gauge, which is necessary as a passage to the treatment bed and the radiation irradiation unit. And a safe medical or work space around the treatment bed.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, a radiotherapy gauge of the present invention is a horizontal cylindrical rotating gantry that rotates in the circumferential direction, a radiation irradiation unit fixed to the rotating gantry, and a rail disposed inside the rotating gantry. The caterpillar is provided so as to be movable along both ends of the caterpillar, and the caterpillar is formed by dividing the caterpillar into at least two parts in the circumferential direction. Caterpillar driving means for pulling and feeding the caterpillar is provided. Further, the present invention is a radiotherapy gauge having a structure in which the radiation irradiation apparatus can be set to be rotated to the optimal irradiation position of the patient, and the rotation path of the radiation irradiation apparatus is sandwiched between the fixed side and the moving side ring rail and divided into a plurality of parts. Synchronizing with the rotation angle of the caterpillar and the radiation irradiation device, a drive cylinder that draws or moves the caterpillar, and a winding function that fills the gap between the divided caterpillars by pulling the drive cylinder By providing the cover which has, the said subject is solved.
[0011]
Further, the caterpillar connected to the cylinder arm is moved by controlling the operation of the drive cylinder according to the rotation angle of the radiation irradiation apparatus, so that a horizontal floor is formed near the treatment bed. That is, the rail is formed to have a horizontal portion, and the caterpillar drive means pulls or sends out the caterpillar divided portion located in the horizontal portion to the radiation irradiation unit side. As a result, a medical technician can approach the patient and a sufficient treatment can be performed.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, as an embodiment of the present invention, a basic configuration of a proton beam therapy apparatus which is an example of a radiotherapy apparatus will be described with reference to FIG.
[0013]
The proton beam generated by the injector 41 passes through the low energy beam transport device 42 and is incident on the synchrotron 43 which is the main accelerator. The synchrotron 43 accelerates the proton beam to the energy required for treatment (usually 100-200 MeV). The proton beam emitted from the synchrotron 43 passes through a high energy beam transport device 44 and is transported to a treatment room having a rotating gantry.
[0014]
Further, the proton beam passes through the beam transport device 11 on the rotating gantry, and is irradiated to the patient on the treatment table 22 through the radiation irradiation device 5 that processes the proton beam into a dose distribution optimal for radiation therapy.
[0015]
The treatment room 45 forms a room with a partition wall from the rotating gantry room. And since the treatment room 45 is set to the floor level near the rotation center ensuring the rotation radius of the rotating gantry, the treatment room 45 is usually 6 to 8 m high with respect to the floor level of the gantry.
[0016]
Therefore, the patient on the treatment table 22 exists in the space of the above height, and the treatment gauge that creates the space surrounding it must be a safe place for the patient and the medical technician.
[0017]
The horizontal cylindrical rotating gantry includes a structure including a front ring 8, a rear ring 9, and a gantry body 10, and a driving unit including a support roll 6 and a gantry rotating motor 7. The front ring 8 and the rear ring 9 are mounted on a plurality of support rolls 6 and rotated as a whole by using a gantry rotation motor 7 connected to the support rolls.
[0018]
A beam transport device 11 and a radiation irradiation device 5 are mounted and fixed on the rotating gantry. On the other hand, a treatment table 22 is mounted on the building, and a drive device is provided that can move so that the patient on the treatment table comes on the rotation axis of the rotating gantry. Therefore, the structure is such that the adjusted proton beam from the radiation irradiation device 5 on the rotating gantry can be irradiated from around 360 degrees of the patient.
[0019]
Next, an embodiment of the present invention will be described in detail with reference to FIGS. 1 is a perspective view of a rotating gantry, FIG. 2 is a longitudinal sectional view of a radiation therapy gauge and a building, and FIG. 3 is a longitudinal sectional view of the rotating gantry as viewed from the opening direction.
[0020]
As shown in these drawings, a treatment gauge is configured to protect the safety of the patient 21 with respect to the rotation path of the radiation irradiating device 5 and for the medical technician 31 and the like to carry out the medical action on the patient. In this treatment gauge, the scaffold for the medical engineer 31 to work is kept horizontal, and a closed space is provided to the other surroundings.
[0021]
The treatment gauge has a caterpillar 1 (divided into three parts, caterpillars A, B, and C in this embodiment) across the rotation path of the radiation irradiation device 5 and is fixed to the ceiling and floor of the building 23. The fixed side ring rail 24 held by the support and the rear panel 29 that closes the depth side of the treatment gauge are supported from both sides by the fixed side ring rail 25 fixed.
[0022]
The moving side ring rail 25 is supported by a plurality of support rollers 27 arranged on the support ring 28. The support roller 27 has a ring rail drive device 26 that adjusts the rotation in the opposite phase to the rotation of the gantry, and the radiation irradiation device 5 rotates forward with the forward rotation of the gantry, but the treatment gauge is stationary. A negative rotation is given so that it can be seen.
[0023]
Each of the caterpillars 1 (A, B, C) has sufficient rigidity, does not deform even when a person rides on the work, and forms a work space around the treatment table 22. In the present invention, the caterpillar 1 is divided into a plurality of parts. However, as shown in the comparative example of FIG. 4, for example, in the case of the caterpillar 2 that is not divided, a gap is formed in a part of the work space by the rotation angle of the radiation irradiation device 5. 3 occurs.
[0024]
This is because the treatment gauge has a kamaboko-shaped cross-sectional shape, so that under the condition that the length of the caterpillar 2 is constant, an insufficient length portion is generated depending on the rotation angle. In order to compensate for this, for example, it is conceivable to attach a work support base 32, a fall prevention cover 33, and the like. However, the distance between the medical technician 31 and the patient 21 is too wide, and the medical technician 31 performs a medical action on the patient. This is insufficient for safety and workability.
[0025]
In the embodiment of the present invention, the caterpillar 1 forming the work space is divided into the caterpillar A, the caterpillar B, and the caterpillar C as described above on the rotational movement path sandwiching the radiation irradiation device 5. The caterpillar C is fixed with respect to the circumferential direction of rotation by a latch 34 with respect to the gantry body 10.
[0026]
Further, two pairs of left and right drive cylinders 4 fed from both side surfaces of the irradiation beam irradiation device 5 are arranged, and the positions of the caterpillar A and the caterpillar B in the circumferential direction are adjusted by the expansion and contraction of the arm 4a of the drive cylinder 4. I was able to control it.
[0027]
And the cover 36 and the cover winder 37 are installed in the connection part of the said caterpillars, ie, the connection part between caterpillar AC, and the caterpillar BC, and between caterpillar A-C and caterpillar B Invented a mechanism to cover the opening between -C. As a result, it was possible to secure a closed space around the patient.
[0028]
Next, the operation of each unit will be described with reference to FIG. FIG. 3 shows a cross-sectional view when the radiation irradiation device 5 is rotated 150 degrees clockwise. Before rotating the radiation irradiation device 5, the cylinder arms 4a of the left and right drive cylinders 4 are pushed out, and the caterpillars A and B are respectively pressed and fixed in the direction of the caterpillar C.
[0029]
The gantry rotation motor 7 is operated according to the rotation command of the radiation irradiation device 5, and the entire rotation gantry is rotated at a speed of about 1 rpm. After reaching the set rotation angle, the rotation is stopped and the rotation is fixed by the brake of the gantry drive system.
[0030]
In this state, the state of the caterpillar is almost the same as the comparative example of FIG. 4, the gap 3 is formed between the radiation irradiation device 5 and the end of the caterpillar, and the medical technician 31 treats the patient 21. To do this, it is necessary to work while confirming the scaffolding.
[0031]
In the present invention, the following functions are added to eliminate the gap 3. The cylinder arm 4a of the drive cylinder 4 installed on the caterpillar A side is pulled, and the caterpillar A is pulled toward the radiation irradiation device 5 side. Thereby, since the medical technician 31 approaches the patient 21 with peace of mind by securing a wide work floor, sufficient medical practice is possible.
[0032]
On the other hand, the caterpillar C is fixed to the gantry body 10 by the latch 34, and therefore does not move in the circumferential direction. Further, in the present invention, a cover winder 37 having a cover 36 made of glass fiber or the like is attached to the connecting portion between the caterpillars A and C.
[0033]
Accordingly, the cover 36 is pulled out in conjunction with the movement of the caterpillar C, and the opening generated by the separation of the caterpillar A and the caterpillar C is covered by the cover 36, so that a continuous closed space can be maintained in appearance. It is possible.
[0034]
Note that when the caterpillar A or B is pushed and connected to the caterpillar C, the drawn out cover 36 is automatically wound around the winder 37. For the structure of the winder, a known technique such as a roll screen or a roll curtain having a structure for maintaining tension in the wind pipe may be applied.
[0035]
As described above, since a necessary horizontal floor is formed by the moved caterpillar A as a passage for approaching the treatment bed and the radiation irradiation apparatus, a safe working space is ensured. At the same time, a closed space is formed by the drawn-out cover 36, so that the patient 21 is not given fear of high altitude.
[0036]
In the present embodiment, only the case where the radiation irradiation device 5 is rotated 150 degrees clockwise is shown, but the left and right caterpillars A or B are operated using the drive cylinder 4 for other arbitrary angles. Thus, a necessary horizontal floor can be secured, and at the same time, the opening generated in the connecting portion between the caterpillars can be closed with the cover 36.
[0037]
In particular, when the radiation irradiation device 5 is rotated 180 degrees clockwise, that is, when the radiation irradiation device 5 comes directly under the treatment table 22, both the left and right caterpillars A and B are attracted using the drive cylinder 4. As a result, a caterpillar horizontal floor is formed around the treatment table 22, and a safe work space can be obtained.
[0038]
FIG. 5 is a structural diagram of the connecting portion between the cylinder and the caterpillar. The connecting structure of both ends (one end of which is the cylinder arm 4a) of the cylinder 4 is a rotatable hinge structure 12, which can freely follow any rotation angle.
[0039]
Further, depending on the rotation angle of the radiation irradiating device 5, the required horizontal floor by the left and right caterpillars A and B is secured by controlling the pushing and pulling of the drive arm 4a of the drive cylinder 4. In the above embodiment, the caterpillar is divided into three parts, but the present invention is not limited to this. What is necessary is just to be divided into at least 2 or more and a horizontal floor is drawn near to the bed.
[0040]
Here, control on the rotation angle of the rotating gantry will be described. FIG. 6 shows a schematic diagram of the control system of the rotating gantry section. When the rotation angle of the gantry is designated from the irradiation control device 51 (for example, a personal computer), a rotation angle command is transmitted to the rotation gantry drive control device 52.
[0041]
Next, when a rotation start command is transmitted, the rotation gantry driving device 53 starts operation, and rotation control of the gantry rotation drive servomotor 55 is started. The rotation angle of the rotating gantry is detected by the rotary encoder 56, and servo control of the rotating angle of the rotating gantry is performed.
[0042]
Simultaneously with the rotation of the gantry, the treatment gate drive control device 57 controls the drive motor 59 so that the floor composed of the caterpillar is kept parallel. Next, when the rotation angle is in the vicinity of the designated rotation angle, the speed is reduced by the speed control of the servo motor 55 for rotation driving, and the rotation stops at the designated position. The stop is performed by a disc brake provided in the gantry rotating part.
[0043]
Next, the cylinder arm 60 of the treatment gate according to the present invention is driven. When the rotation angle of the gantry is 0 ° to 133 °, the gap between the caterpillar and the irradiation nozzle is small, and it is necessary to drive the cylinder. Absent.
[0044]
From a rotation angle of 133 degrees to 165 degrees, it is necessary to draw the cylinder on one side. Furthermore, at 165 ° to 190 °, the medical engineer can access from both sides of the irradiation nozzle, so both cylinder arms are drawn. Therefore, when the user designates the rotation angle from the irradiation control device, it is possible to designate the driving of the cylinder after stopping the rotation.
[0045]
In practice, limit switches 54 are provided at 133 degrees and 165 degrees to ensure safety. After reaching the specified angle of the gantry, the controller determines that there is a mechanical limit switch operation signal, and the cylinder is driven. This is a system in which the limit switch 54 confirms the fact that the rotating gantry has rotated within a specified range.
[0046]
As described above, according to the embodiment of the present invention, even when the rotating gantry rotates, the divided caterpillar ensures a necessary horizontal floor for approaching the treatment bed and the radiation irradiation apparatus. Since this horizontal floor can close the inner peripheral surface of the rotating gantry without any gap between the radiation irradiation devices, a safe working space can be obtained.
[0047]
At the same time, a cover that can be pulled out or wound in conjunction with the split movement of the caterpillar is provided at the opening of the split part between the caterpillars. On the other hand, no fear of high altitude is given.
[0048]
【The invention's effect】
As described above, according to the present invention, the inside of the radiation therapy gauge is always a closed space without depending on the rotational position of the radiation irradiation device, and a horizontal bed necessary as a passage to the treatment bed and the radiation irradiation unit is formed, and treatment is performed. A safe work space can be installed around the bed.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a rotating gantry according to the present invention.
FIG. 2 is a longitudinal sectional view of the radiation therapy gauge and building of the present invention.
3 is a longitudinal sectional view of the rotating gantry of FIG. 1 as viewed from the opening direction.
FIG. 4 is a longitudinal sectional view showing a comparative example of the present invention.
FIG. 5 is a structural diagram showing an example of a cylinder connecting portion in the present invention.
FIG. 6 is a schematic diagram showing an example of a control system for the operation of the rotating gantry according to the present invention.
FIG. 7 is a configuration diagram showing an example of a proton beam therapy apparatus to which the present invention is applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, A, B, C Caterpillar 2 Caterpillar 3 Crevice 4 Drive cylinder 4a Cylinder arm 5 Radiation irradiation apparatus 6 Support roll 7 Gantry rotation motor 8 Front ring 9 Rear ring 10 Gantry fuselage 11 Beam transport apparatus 21 Patient 22 Treatment table 23 Building 24 Fixed side ring rail 25 Moving side ring rail 26 Ring rail driving device 27 Support roller 28 Support ring 29 Rear panel 31 Medical engineer 32 Work auxiliary table 33 Fall prevention cover 34 Latch tool 36 Cover 37 Cover winder 41 Injector 42 Low energy Beam transport device 43 Synchrotron 44 High energy beam transport device 45 Treatment room

Claims (5)

A rotating gantry that rotates in the circumferential direction in a horizontal cylindrical shape, a radiation irradiation unit fixed to the rotation gantry, and provided at both ends of the radiation irradiation unit so as to be movable along a rail disposed inside the rotation gantry. and a linked caterpillar on, the caterpillar is formed by divided into at least two circumferentially, or feed or attract each caterpillar in a connecting part between the radiation irradiation section of the divided caterpillar tracks Radiation therapy gauge provided with driving means. The radiotherapy gauge according to claim 1, wherein the caterpillar driving unit pulls the caterpillar in and out in synchronization with a rotation angle of the radiation irradiation unit. The radiotherapy gauge according to claim 1, wherein the caterpillar dividing portion has a cover that is drawn out so as to close an opening between the caterpillars. The radiotherapy gauge according to claim 3, wherein the caterpillar split portion includes a winder that winds up the cover as the caterpillars approach each other. 2. The rail according to claim 1, wherein the rail has a horizontal portion, and the caterpillar driving means draws and sends out the divided portion of the caterpillar located in the horizontal portion to the radiation irradiation unit side. The radiation therapy gauge of any one of thru | or 4.

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