JPH03143455A - Multi-divided profiling apparatus - Google Patents

Abstract

PURPOSE:To prevent an apparatus from increase in size and to form an irradiation field conformable to the shape at a deseased part by preparing at least a pair of collimaters by combining movably in the opening and closing directions a plurality of collimater structures divided in the width direction and communicating collimater structures of each group to a common link. CONSTITUTION:A component in the direction X in an irradiation field is formed with a pair of collimaters 21A and 21B and is moved at a specified amt. by each driving apparatus 23 provided each correspondingly. Then, an outer part in the direction Y is formed with collimater plates 28 and 28 of a pair of multi- divided collimaters 22A and 22B and the collimater plates 28 and 28 of each group are moved through a rack 27 by means of each driving apparatus 23 and the collimaters 28 and 28 connected with linking bodies 29 and 29 move in the direction Y. An irradiation field corresponding to a deseased part is thus formed with collimaters 21A and 21B and multi-divided collimaters 22A and 22B.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Use) The present invention relates to a multi-segmented diaphragm device for determining a radiation irradiation range in a radiotherapy device or the like.

(Prior art) The current 7F-, known radiotherapy equipment is, for example, the 16th
It has the configuration shown in the figure. That is, the fixed pedestal 1,
A rotary pedestal 2 is provided on the fixed pedestal 1 so as to be rotatable in the direction of arrow A, an irradiation head 3 is attached to one end of this rotary pedestal 2, and a irradiation head 3 is attached to the lower part of the head 3 to rotate in the direction of arrow B. A diaphragm device 4 is mounted on the diaphragm 4, and a diaphragm 5 is mounted on the other end of the rotating frame 2, facing the diaphragm device 4.
and a bed device 6 which is rotatably provided on the floor and which can be rotated in the direction C in the figure around the center O of 6A; It rotates in the direction nJ and moves in the directions of arrows E, F, G.

Here, the irradiation head 3 and the aperture device 4 will be explained with reference to FIG. 17. The irradiation head 3 is composed of an electron gun 3A, an acceleration tube 3B, and a shielding part (43C).The iris device 4 is used to restrict the radiation generated from the radiation 1.1 radiation source S provided at one end of the acceleration tube 3B.

The conventional aperture device 4 includes upper aperture bodies 8A, 8B and lower aperture bodies 9A, 9B arranged in a grid pattern below the radiation iiS.
, a drive device that drives each aperture body individually, and a detection device (none of which is shown) that is attached to each of these drive devices and detects the amount of movement of the aperture body. Then, as shown in FIGS. 7 to 9, the upper aperture bodies 8A, 8
B and the lower aperture bodies 9A and 9B are moved toward and away from each other in the X and Y directions on concentric circles centered on the radial q/1 line aqS, and the shape of the lesion T is z as shown in Fig. 1O.
) to form a firing field U of arbitrary size.

However, in this type of squeezing device, the lesions T are generally circular and oval solid, whereas the lesions formed! The Ia radiation field U has the disadvantage that only a rectangular shape can be obtained and the radiation reaches the healthy tissue around the lesion.

Therefore, recently, a multi-segment diaphragm device that has improved this drawback has been used. This diaphragm device is shown in Figure 11 or 1.
As shown in FIG. 3, a pair of aperture bodies 10A facing each other on the upper side,
IOB, multi-segmented aperture bodies 11A and IIB located at the bottom and divided into 21 parallel parts in the radial direction, and a drive device 13
and a detection device (not shown) that is individually attached to the drive device 13.

The pair of aperture bodies 10A and IOB are provided so as to move toward and away from each other in the X direction on a concentric circle that includes the radiation R6 as a central axis. The multi-segmented aperture bodies 11A and IIB are
A plurality of divided aperture plates 12.12 are combined in a mutually movable manner, and these aperture plates 12.1
2 are provided so as to move in the Y direction on a concentric circle including the radiation source S as the central axis, approaching and moving away from each other. A pair of aperture bodies 10A, an IOB and a multi-segment aperture body 11A
, IIB by moving and combining the plurality of aperture plates 12.
ET field U is formed. The drive device 13 includes a pair of aperture bodies]OA.

10B individually, and a pair of multi-segmented aperture bodies 1.
The aperture plates 12 and 12 of IA and IIB are individually driven.

However, this conventional multi-segment diaphragm l) device has the following problems.

A plurality of temporary apertures 1 constituting the multi-segment aperture bodies 11A and IIB
In order to move the apertures 12.12 by slightly different amounts of movement, a dedicated drive device 13 and a detection device are provided to individually drive each temporary aperture 12.12.

However, in order to drive the aperture plate 12.12 independently, the driving device 13 and the detection device are required to drive the aperture plate 12.12 as described above.
12 numbers are required, and multi-segmented aperture bodies 11A and 11B are required.
If the number of diaphragm plates 12,] 2 that divide the diaphragm is increased, the number of driving devices 13 and detection devices will increase accordingly, which will increase the product cost, and the space for installing these devices will also increase. The entire device becomes larger. On the other hand, if the number of aperture plates is small, a multi-segment aperture body 11A as shown in FIG.
, An arbitrary irradiation field can be obtained in the opening/closing direction (Y direction) of 11B, but since the division angle cannot be arbitrarily changed in the division width direction (X direction), a small irradiation field (such as 'BIX 3 mm) can be used to obtain a healthy area around the lesion. Radiation may be irradiated to the Mi weave (problem to be solved by the invention) As mentioned above, when the number of divisions in a multi-segment drawing device is increased, the mechanism becomes complicated, the product cost increases, and the volume of the device increases. also increases. Furthermore, if the number of divisions is small, there is a problem that highly accurate irradiation cannot be specified.

The present invention has been made based on the above-mentioned circumstances, and is an economical multi-segmentation type aperture device that can form one radiation point/one field that matches the irregular lesion shape due to multi-segmentation while preventing the increase in size. The purpose is to provide

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the multi-segmented diaphragm device of the present invention includes a pair of diaphragms that move in a mutually openable and closable manner surrounding the radiation flux emitted from the radiation source. In a device that sets a radiation flux irradiation range by moving the aperture bodies of each village in an opening/closing direction relative to each other, the at least one pair of aperture bodies is composed of a plurality of aperture body structures divided in the width direction. The aperture body assemblies are assembled so as to be movable in the opening and closing directions, and these aperture body assemblies are grouped together into a plurality of groups, and the aperture body assemblies of each divided group are connected to a common link body. It is characterized by the fact that

(Function) In the multi-segmented aperture body, the entire aperture body structure that constitutes the key can be driven by the links for each set, so
The entire diaphragm structure of the multi-segment diaphragm body can be moved and continuously deformed. Therefore, it is possible to flexibly move the aperture body of the multi-divided aperture body using the same number of driving devices as the number of divided groups, and to set the required sheet weight, brightness and i-field of one beam bundle.

This makes it possible to drive a multi-segmented diaphragm body having a required number of diaphragm body structures with a small number of drive devices.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

An embodiment of the multi-segment diaphragm device of the present invention will be described with reference to FIGS. 1 to 4.

As shown in FIGS. 1 to 3, the multi-segment diaphragm device of this embodiment includes one diaphragm body 21A, 21B disposed below the radiation source S, and a pair of diaphragm bodies 21A, 21B.
A pair of multi-segmented diaphragm bodies 22A, 22B arranged below and perpendicular thereto form a space defining an irradiation field of the radiation flux, and a pair of diaphragm bodies 21A, 21B. and a pair of multi-segmented aperture bodies 22A.
A drive device 23 that drives 22B and this drive device 23
It is equipped with a detection device 24 attached to the.

The pair of aperture bodies 21A and 21B located above have a rectangular parallelepiped shape when viewed from above and an arc shape from the front, and are made of heavy metal. The pair of aperture bodies 21A and 21B are arranged opposite to each other across a vertical line passing through the radiation source S, and as shown in FIG. They are provided so that they move independently in the X direction on a fixed arc that approaches and moves away from each other. The pair of aperture bodies 21A and 21B are individually moved by corresponding dedicated drive devices 23, respectively. A detection device 24 is provided corresponding to the drive device 23. The drive device 23 includes a motor 25 and a gear 26 rotated by the motor 25, and the gear 26 is the aperture body 21A.

It meshes with a rack 27 formed in the direction of movement of the rack 21B. Note that although a gear structure is actually composed of a plurality of gears, one gear 26 is symbolically shown here for the sake of explanation.

By rotating the gear 26 in a predetermined rotation direction at a predetermined number of rotations by the motor 25, the aperture bodies 21A and 21B are moved by a predetermined amount in a predetermined direction via the rack 27. The detection device 24 uses, for example, a potentiometer that receives rotation from the gear 26 of the drive device 23 and rotates to detect the amount of movement of the aperture bodies 21A, 21B. One set of drive devices 23 and one set of detection devices 24 are combined as one set of units, and one set of units is arranged for each aperture body 21A, 21B at a position corresponding to the aperture body 21A, 21B, and a frame ( (not shown).

A pair of multi-segmented aperture bodies 22A22B located below are arranged to face each other in the Y direction perpendicular to the X direction with the vertical line passing through the radiation eclipse S as the center. The pair of multi-segmented aperture bodies 22A, 22B are constructed by arranging and assembling a plurality of aperture plates 28, 28, which are aperture bodies obtained by dividing each in the trunk direction, in the radial direction. These diaphragm plates 28, 28 move independently in the Y direction along a solid arc drawn with the radiation source S at the center, approaching and separating from each other by a combination of protrusions and grooves formed along the movement direction. It is being scrutinized like this. In addition, the multi-segmented aperture body 22A,
Aperture plates 28 and 28 located at both ends of 22B are movably supported by members such as rollers (not shown).

The multi-segmented aperture bodies 22A and 22B each have a temporary aperture of 28.2
8 are grouped into groups according to a plurality of adjacent aperture numbers, and in each of these groups, a plurality of aperture temporary 28.28 constituting the group are connected by a common link body 29.2. That is, two link bodies 29 are arranged on the upper surface of the aperture plate 28, 28, for example, according to each group. These two link bodies, the two centers are connected to the aperture plate 28, 28 by a bottle 30.30 protruding from the aperture plate 28.
8.28, and a plurality of elongated holes 31 extending in the j direction along the length nozzle in the other parts, the bottles 30 protruding from the other diaphragm plate 28 are fixed to the movement amount (+). There are two links in each set next to each other, and the two ends are
It is connected by a pin 30.30 protruding from the aperture plate 28.28.

In other words, the pin 30.3 protruding from the temporary aperture 28.28]
] is common to the elongated hole 31.31 of each adjacent link body 29.29, and both link bodies 29.2 are connected.

In each set, when the link body 29.29 rotates around the eye point formed by the pin 30.30, the bottle 30.30 inserted into the elongated hole 31.31 is given a force, and each aperture ring 28.28
are individually moved along the Y direction by a predetermined amount. Furthermore, by interconnecting the two link bodies of each adjacent set, the two link bodies are moved in the same direction, and the movement of the aperture plate is continuous across each set. Can be done. In this way, in the multi-segmented aperture bodies 22A and 22B, the aperture plates 28.28 are configured to be continuously displaceable by connecting the temporary apertures 28.28 with link bodies 29.29 to form a chain structure. Figure 4 shows a multi-segmented aperture body 22A.
is shown enlarged.

Further, in the pair of multi-segmented aperture bodies 22A and 22B, one aperture plate 28 is assigned to each group, and one aperture plate 28,28 assigned to each group is driven by a corresponding dedicated drive device 23. They are designed to move individually. Further, a detection device 24 is also provided corresponding to the drive device 23.

As described above, this drive device 23 includes a motor 25 and a gear 26 rotated by the motor 25, and this gear 26 has a rack 26 formed along the movement direction of the aperture.
It meshes with 7. By rotating the delivery vehicle 26 in a predetermined rotation direction and at a predetermined number of rotations by the motor 25, each group of temporary apertures 28, 28 is moved a predetermined amount in a predetermined direction via the rack 27. When each set of aperture plates 28.28 moves, each set of link bodies 29.29 operates via a bottle 30.30 protruding from this aperture plate, and these link bodies 29.
．． Each set of temporary diaphragms 28 and 28 connected to 29 through pins 30 and 30 move in the Y direction.

In this way, the aperture plates 28, 28 are individually moved for every six sets using the dedicated drive device 23. Note that the reason why one diaphragm plate 28 is assigned to each group and only that diaphragm plate 28 is driven by the drive device 23 is that by driving one diaphragm plate 28, the group is constituted by two link bodies. This is to drive the entire temporary diaphragm 28 in a negative direction.

For example, the detection device 24 receives the same rotation from the gear 26 of the moving device 23 and rotates in the same manner, thereby detecting the multi-segmented aperture body 22A,
A potentiometer is used to detect the amount of movement of 22B. 11I'I drive device 23 and one set of detection device 2
4 are put together as one set of units, and one set of units is arranged at a position corresponding to the aperture temporary 28.28 assigned to each set of the multi-divided aperture bodies 22A, 22B, and a frame (not shown) is assembled. ).

The operation of the multi-segment diaphragm diaphragm device constructed in this way will be explained.

For example, it is assumed that a radiation field 11 ((()) is formed that sufficiently includes a lesion T having the shape shown in FIG.

First, the X-direction component of y, ((ray'!f In other words, the aperture body 21A
, 21B, drive the motor 25 to rotate the gear 26 in a predetermined rotational direction at a predetermined rotational speed, thereby driving the aperture body 21A through the rack 27.

21B by a predetermined amount in a predetermined direction.

Next, the outer contour in the Y direction in field U is formed by the aperture plates 28 and 28 of the pair of multi-segment aperture bodies 22A and 22B. For this reason, the multi-segmented aperture body 22A.

22B, the temporary aperture 28.28 is
It is moved by an amount of movement corresponding to the component in the Y direction in field U. That is, the multi-segmented aperture body 22A.

The rack 27 is rotated by driving the motor 25 of each drive device 23 provided corresponding to the aperture plate 28. Through each set of aperture N28.28
F hyperactivity by a predetermined amount in a predetermined direction. &III's aperture temporary 28.28 respectively [if hyperactive, this aperture value 28.2
6 sets of link bodies 29.2 via fins 30 protruding from 8.
9 is operated, and each set of aperture bells 28, 28 connected to these link bodies 29, 29 via pins 30 moves in the Y direction. In this way, the multi-segmented aperture body 22A is formed.

Temporary aperture of 22B is 28.28! Each multi-segment aperture body 22A moves in accordance with the Y-direction component of the 1G shooting field U.

YJj of irradiation field U with aperture plate 28.28 at 22Bm
Forms a line that changes continuously according to the outline of the direction.

In this way, the aperture bodies 21A, 21B and the multi-division count body'
) ') A and 22 B form a photogenic field U corresponding to the lesion T.

In addition, in the case of fixed bile 11, radiation is irradiated in this state.
・In the case of quadrilateral elbow, it is sufficient to move the squeezing body and multi-segmented aperture body according to the shape of the lesion according to the rotation angle of the gantry, or to rotate the aperture device itself. Forms an irradiation field that matches the shape of the lesion.

Therefore, in the multi-segment diaphragm device of this embodiment, the driving device 23 for driving one temporary diaphragm 28, 28 is provided in each group divided by the link bodies 29, 29 in the multi-segment diaphragm bodies 22A, 22B. The driving device 23 drives one temporary diaphragm 28.28 for each group, and the two links drive the entire diaphragm plate 28.28 that constitutes each group. The number of aperture plates 28, 28 that corresponds to the number of groups in the multi-segment aperture bodies 22A and 22B is sufficient.
Compared to the case where the same number of drive devices are provided, the number of drive devices 23 provided is reduced to a thick shaft. Therefore, the second space for housing the drive device 23 and the detection device 24 is also reduced.

And the aperture plates 28.2 of the multi-segment aperture bodies 22A and 22B.
8 can be provided as many times as required without being limited to the number of drive devices 23. Therefore, the irradiation field can be regulated in contact with the outline of the lesion, and the irradiation field can be placed between the lesion and the vessel.
It is possible to minimize the radiation dose Lj to the healthy tissue around the lesion, and to apply even and maximum bkl to the lesion.

It should be noted that the present invention is not limited to the above-mentioned examples.

For example, in the embodiment, the lower aperture body is divided into multiple aperture bodies 22A, 22.
B, but the present invention can be applied by using the pair of aperture bodies 21A and 21B, which are upper aperture bodies, as multi-segment aperture bodies in place of the lower aperture body.

Further, the present invention can be applied by using both the upper aperture body and the lower aperture body as multi-segment aperture bodies.

Furthermore, the number of diaphragm plates constituting the multi-segment diaphragm body is not limited to the above-described embodiment, and a larger number of diaphragm plates can be temporarily combined. FIG. 6 shows an embodiment in this case, which is connected to the diaphragm temporary 28.28 shown in FIG. Further, the two link bodies 29 are provided independently and evenly spaced.

[Effects of the Invention] As explained above, according to the multi-segmented aperture device of the present invention, a plurality of aperture body assemblies constituting an opening body are moved in the opening/closing direction (combined into an L), and these edge body assemblies is grouped into a number set for each of the adjacent aperture body transverse bodies, and the aperture body purchase units for each set are connected by a common link body, so the multi-divided aperture body can be linked for each set. By driving the body,
By moving each set of diaphragm body structures in the opening and closing directions, the entire diaphragm body structure can be made to continuously protrude. For this reason,
The aperture body structure of the multi-segmented aperture body makes it possible to form an irregular radiation irradiation field depending on the lesion.

Therefore, by simply using the same number of driving devices as the number of divided sets of the aperture bodies of the multi-segmented aperture body, the aperture bodies (14 units) of the multi-segmented aperture body can be flexibly moved to irradiate the required radiation flux. This makes it possible to drive a multi-segmented diaphragm body with a required number of diaphragm body assemblies using a small number of drive devices.

As a result of this, the cost required for the driving device can be significantly reduced and the product cost can be lowered, and at the same time, the space for installing the driving device can be reduced and the expansion of the size of the aperture device can be avoided.

Furthermore, since it is possible to provide as many drive devices as required without being limited to the number of driving devices for the multi-segmented aperture body, the irradiation field can be regulated in contact with the outer contour of the lesion, and area, and it is possible to uniformly give the maximum radiation dose to the lesion while minimizing the radiation dose to the healthy tissue surrounding the lesion.

[Brief explanation of the drawing]

Figures 1 to 4 show the major implementation of the present invention.
Figures 3 through 3 are diagrams showing the schematic configuration of the multi-segmented aperture device, Fig. 4 is an enlarged view of the multi-segmented aperture body in the multi-segmented aperture device, and Fig. 5 shows the lesion and radiation field. , FIG. 6 is a diagram showing another embodiment of the multi-segment type diaphragm, FIGS. 7 to 10 show a conventional example, and FIGS. 7 to 9 are views of the multi-segment diaphragm. Figure 10 is a diagram showing the schematic configuration, Figure 10 is a diagram showing the lesion and radiation field, Figure 11 is a diagram showing the schematic configuration.
14 to 14 show other conventional examples, and FIGS. 11 to 13 show schematic configurations of multi-segmented aperture devices,
Figure 14 is a diagram showing the lesion and the 9th and 1st radiation fields.
FIG. 5 is a diagram showing the formation of the radioradial η/I fields, FIG. 16 is a diagram showing the radiation therapy device, and FIG. 17 is a diagram showing the radiation irradiation section of the radiation therapy device. 21A, 21B... Aperture body, 22A, 22B... Multi-segment aperture body, 28.28... Temporary aperture, 29.29...
・Link body.

Claims (1)

[Claims] In an apparatus in which a pair of aperture bodies that surround a radiation flux emitted from a radiation source and move in an openable and closable manner are combined, and each pair of aperture bodies moves in the opening and closing direction to set the irradiation range of the radiation flux. , at least one pair of aperture bodies are
It is constructed by combining a plurality of aperture body structures divided in the width direction so as to be movable in the opening/closing direction. A multi-segment diaphragm device characterized in that the diaphragm body structure is connected to a common link.