JPS6160706B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is particularly applicable to cobalt in radiotherapy.
60. A high-energy rotational radiation therapy device that irradiates the affected area with high-energy gamma rays or electron beams such as isotope or linear accelerator, and treats malignant neoplasms (cancer cells) using the ionization energy of the radiation. Regarding.

Conventional devices of this type fix a specific point on the affected area on the rotation axis of the gantry frame and irradiate the affected area centering on the specific point while rotating the gantry frame. Because it has a method and configuration that irradiates a specific point over a number of times, the distance between the irradiation source and a specific point on the affected area is fixed.
There is a limit to the space between the device and the patient supported on the bed, and positioning has to be done while taking into account the risk of collision between the device and the patient. For this reason, even for patients who require rotational irradiation treatment, this treatment cannot be performed due to the limited space between the device and the patient. That is, rotational radiation therapy has been performed using a configuration as shown in FIG. This figure is from the document 1973 "Physics of Medical Biology".
History, theory and current status of accelerators”
(PHYS.MED.BIOL 1973, VOL.18, No.3,
“EIectron Linear Accelerator For Radiation
Therapy：History, Principles and
Contemporary-Developments：By CJ
Karzmark and NC-Pering). In FIG. 1, a stand 1, a gantry frame 2, a bed 3, a radiation source 4, an isocenter 5, and a rotation locus 6 of the gantry frame are shown. In addition, rotational treatment using electron beams cannot be easily performed with the above configuration, so it has not been common.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a rotational radiation therapy apparatus that can freely perform rotational treatment around a specific point regardless of the patient's position, while eliminating the conventional drawbacks.

According to the present invention, there is provided a means for setting a distance between a radiation source attached to a gantry frame and a specific point on an affected area to a predetermined distance, and a means for rotating the gantry frame while always maintaining the set distance. By providing a means for controlling the position and/or rotational axis of the treatment table according to the angle, the above drawbacks can be solved and the treatment table can be freely centered at a specific point regardless of the size of the patient or the position of the affected area. It becomes possible to perform rotational treatment, and it is also possible to obtain a rotational radiation therapy apparatus capable of performing rotational treatment using electron beams, which is not very common.

The configuration of the invention includes a radiation source such as cobalt-60,
A rotating radiation irradiation device in which a gantry frame equipped with a betatron, a linear accelerator, etc. rotates around a fixed point (isocenter) in space and irradiates radiation such as gamma rays, X-rays, or electron beams; A treatment table that supports the patient,
A remote control device for the device, a selection control device for the distance between the radiation source and the specific point of the affected area, a gantry frame rotation angle position reading device, a treatment table position reading device, a treatment table lifting device, and a treatment table lifting device. The treatment table is raised and lowered according to the rotation angle of the gantry frame using a signal set by selecting the distance between the radiation source and the specific point of the affected area and a signal of the rotation angle position of the gantry frame. and the slide drive are simultaneously controlled, and furthermore, the elevation and descent of the position of the rotating shaft and the slide drive are simultaneously controlled so that the distance between the radiation source and the specific point of the affected area is always maintained constant.

Next, the present invention will be described in detail with reference to the drawings of an embodiment of the present invention. FIG. 2 is a block diagram of control based on the position of the treatment table in the present invention. The figure shows gantry frame 7 and rotation drive unit 8.
Rotation angle reading unit 9, remote control unit 10, treatment table position control unit 11, radiation source/specific point distance control unit 12,
A treatment table 13, a treatment table position reading section 14, and a treatment table elevating/bed sliding movement drive section 15 are shown.

FIG. 3 is a diagram showing the first embodiment of the present invention, in which a 4 MeV linear accelerator is used as the rotational treatment device. Figure 3 a, b, c
show different usage conditions, especially Fig. 3 c.
indicates lateral radiation. In the figure, an X-ray head 16, a gantry frame 17, a treatment table 1
8, a bed 19, a source position 20, a specific point 21, a linear accelerator tube 22, and an accessory mount 23 are shown. In the case of a 4MeV linear probe, for example, the height of the isocenter is 123cm,
When the distance between the radiation source and the isocenter is 80cm, the maximum irradiation field at the isocenter is 32 x 32cm, and the distance between the X-ray head 16 and the isocenter is 40cm, the accessory mount 23 is installed to further focus the X-rays below the head 16. When equipped, the above 40cm will be shortened to approximately 30cm. The width of the bed 19 of the treatment table 18 is 50 cm, so the sliding range in the left and right direction is 5 cm.
Almost impossible to adjust. According to the present invention, when the distance between the radiation source and the specific point of the affected area is selected as 100 cm, the adjustment range is
The beam length is 25cm, making it possible to perform rotational irradiation on most affected areas.

Furthermore, since a wealth of treatment data is generally obtained with a distance between the radiation source and the affected area of 100 cm, it is now possible to utilize the abundant data available in the past.

Next, a 20 MeV linear accelerator will be explained with reference to FIG. 4 showing a second embodiment of the present invention. FIGS. 4a, b, and c are views corresponding to FIGS. 3a, b, and c, respectively, and FIG. 4d is a partially enlarged view of FIG. 4c, showing the X-ray head 24,
Gantry frame 25, treatment table 26, bed 27,
A radiation source position 28, a specific point 29, a linear accelerator tube (electron beam acceleration section) 30, a bending magnet (a magnet that deflects the direction of the electron beam by 90 degrees or 270 degrees) 31, an electron beam collimator 32, and A specific point 33 (not fixed but angularly variable) on the patient's outer ring septum is shown.
In the case of a 20MeV linear strike, for example, the height of the isocenter is 130cm, and the distance between the source and the isocenter is
100cm, maximum isocenter field 35 x 35cm,
Distance between X-ray head 24 and isocenter is 45cm
In this case, the electron beam collimator 3 is placed below 24.
When equipped with 2, the 45cm mentioned above becomes 5cm. When rotating electron beam irradiation is performed, this device has a radiation source-to-skin distance controller to maintain an equal distance of 5 cm from the patient's body surface. Furthermore, in this case, the isocenter is lowered and the center of rotation is set at 100
If you want to perform rotational treatment while maintaining the radiation source at
It is possible to control the distance between isocenters to 130cm.

As explained above, by making the rotational irradiation center variable, the present invention expands the range of patient positioning and lowers the isocenter to facilitate positioning of the affected area. This has the effect of making it possible to irradiate a uniform dose along the interval.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional rotational radiotherapy device;
FIG. 2 is a diagram showing the configuration of the control system of the present invention, FIG. 3 a, b, and c are diagrams showing one embodiment of the present invention, and FIG. The figure which shows the example of.

Claims (1)

[Claims] 1. A rotating radiation irradiation device that irradiates radiation, a treatment table that supports the patient, a remote control device for the rotating radiation irradiation device, a control device for selecting the distance between the radiation source and the specific point of the affected area, and a gantry frame rotation angle position reading device , a treatment table position reading device, a treatment table elevation drive device, and a treatment table bed slide drive device, and is equipped with a signal set by selecting the distance between the radiation source and the affected area specific point and rotation of the gantry frame. The angular position signal simultaneously controls the elevation and slide drive of the treatment table according to the rotation angle of the gantry frame, and simultaneously controls the elevation and slide drive of the rotation axis position to constantly maintain the distance between the radiation source and the specific point of the affected area. A rotating radiation therapy device characterized by constant maintenance.