JP3460957B2 - Radiation therapy equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of irradiating a three-dimensionally and accurately focused radiation to an affected part without exposing a part other than the affected part as much as possible. The present invention relates to a radiotherapy device capable of performing treatment. 2. Description of the Related Art A conventional radiation therapy apparatus using a rotary irradiation method is configured, for example, as shown in FIG. In the figure, reference numeral 31 denotes an apparatus main body, 32 denotes a housing that houses the radiation generating apparatus, and the housing 32 is a horizontal member including a patient's diseased part I on a treatment table 33 horizontally supported by a support 33A. (in the figure y axis) axis is rotatably organized around. Numeral 34 denotes an X-ray generator housed in a housing 32, 3
Reference numeral 5 denotes a first-stage collimator for limiting an irradiation area (hereinafter, referred to as an “irradiation field”) of the X-rays emitted from the X-ray generator 34, and reference numeral 36 denotes a pair of collimator leaves 36A for X-rays from the first-stage collimator 35. , 36B in the y direction and its
A Y collimator (see FIG. 10 ) for moving and restricting the X-rays restricted by the Y collimator 36 in the opposite direction (y-axis direction) further moves the pair of collimator leaves 37A and 37B in the x direction and the opposite direction (x This is an X collimator that moves and restricts in the axial direction . Next, the operation will be described. In the case of the radiotherapy apparatus shown in FIG. 9, the X-rays generated by the X-ray generator 34 are first restricted by the first-stage collimator 35 fixed in the housing 32, and then the Y-collimator 36 changing the opening degree by driving the irradiation field in the y-axis direction in this collimator 36 is limited symmetrically to x axis, further, changing its opening degree by driving the X collimator 37, the collimator 37 And the irradiation field in the x- axis direction is y
To reach the affected area I symmetrically to the axis in a restricted state. Then, by rotating the housing 32 about the y axis,
The X-ray irradiation direction is changed by 360 ° to reduce the exposure dose to the normal tissue by dispersing it within the x- axis- z- axis plane (shown in FIG. 11B) as shown in FIG. Next, the operation will be described. To treat a patient, first, the position of the affected area I in the patient and the affected area I
Is determined by a diagnostic device such as an X-ray CT, and then the treatment planning device determines the electron beam to be irradiated, the type of X-ray, the energy, and the irradiation field. When performing treatment, radiation is applied to the diseased part I within the x- axis- z- axis plane while the casing 32 rotates up to 270 ° in the left and right direction of the patient around the diseased part I of the patient on the treatment table 33. Affected area I by two-dimensional irradiation
Treatment. When three-dimensionally irradiating the diseased part I, the setting state of the patient is changed, the diseased part I is positioned again, and then two-dimensionally radiated. However, in the case of the conventional radiation therapy apparatus shown in FIG.
6, the collimator leaves 36A, because 36B is not driven only be symmetrical positions from each other in the <br/> about the x axis, the absorbed dose of X-rays of the housing 32 is rotated to the normal tissues even in the disperse, x axis as shown in FIG. 11 -
There has been a problem that X-rays cannot be sufficiently dispersed only by dispersing the z- axis plane (shown in FIG. B) , and the exposure dose to normal tissues cannot be ignored. SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a radiation therapy apparatus capable of dispersing an irradiation dose to normal tissues in three dimensions, thereby suppressing an exposure dose to normal tissues. It is an object. A radiotherapy apparatus according to the present invention rotates an irradiation field around a patient in a vertical plane in a Y direction.
The radiation field of the Y collimator is moved in the Y direction and released.
The radiation is scanned in the Y direction, and the treatment table is moved with the movement of the Y collimator.
By moving in the same direction in conjunction, the radiation
While changing the incident angle to the affected area of the patient, from around the affected area
It is designed to emit radiation. According to the radiation therapy device of [0008] the present invention, release incident angle to the affected area of the ray is changed, it is irradiated from different directions with respect to the affected part, to disperse the exposure dose of radiation on normal tissues Can be. [Embodiment 1] As shown in FIG. 1, the radiation therapy apparatus of the present embodiment includes a fixed apparatus main body 131 and a casing 132 as a rotating body rotatably disposed in the apparatus main body 131. An irradiation unit (X-ray generator) 134 for irradiating radiation, a first-stage collimator 135 for limiting a radiation irradiation field from the X-ray generator 134 are moved in the y direction and the opposite direction (y-axis direction). Collimator 136 to limit the irradiation field by the x-direction and vice versa
Direction (x-axis direction orthogonal to the y-axis line)
And an X collimator 137 for limiting the irradiation field, and is configured to treat the affected part I of the patient on the treatment table 133 with radiation whose irradiation field is limited by each of the collimators 135, 136, and 137. The plurality of collimators 135, 1
Of 36,137, Y to limit the y-axis direction of the irradiation field
The collimator 136 creates a narrow irradiation field centering on the irradiation source of the X-ray generator 134 and sets the irradiation field to the entire range (the range from A to B in FIG. 2) of the opening degree of the first stage collimator 135 in the y- axis direction. It swings over. On the other hand, the treatment table 133 is configured to move so as to irradiate the affected area I with radiation at all positions in the swing range in conjunction with the swing operation of the Y collimator 136. That is, the Y collimator 136 is shown in FIGS.
As shown in FIG. 7, a pair of arc-shaped collimator leaves 136 are formed.
A and 136B, each of which is configured such that the degree of opening can be adjusted to irradiate the affected part I with an optimal radiation dose.
Then, this Y collimator 136 is, for example,
When irradiating the affected part I by moving to the position shown in FIG. 2, the radiation from the first collimator 135 is almost blocked by one collimator leaf 136B, and only the affected part I is irradiated.
When irradiating the affected part I by moving to the position shown in FIG. 3, the radiation from the first collimator 135 is almost blocked by the other collimator leaf 136A as shown in FIG. And the Y collimator 136 is A
Can be set to move from the position B to the position B in a plurality of stages, and the treatment table 133 moves in conjunction with this and moves from the position shown in FIG. 2 to the position shown in FIG. At the set position, radiation is irradiated to the affected part I. As shown in FIGS. 2 and 3, a housing 132 for accommodating the X-ray generator 134 and the like is provided with a Y collimator 1.
Radiation is irradiated is to be able to irradiate three-dimensional in the x-axis -z axis plane at each position and to rotate 360 ° about the y axis for each of the movement positions of the 36. As described above, according to this embodiment, Y
The collimator 136 is sequentially moved around the diseased part I, and the angle of incidence of the radiation on the diseased part I changes as shown by the hatched area in FIG. The treatment can be performed, and thus, in normal tissues other than the affected area, the radiation is dispersed in a spherical shape, so that the exposure dose to the normal tissues can be reduced. Further, the above-mentioned radiation treatment apparatus includes a radiation treatment planning apparatus shown in FIG. This radiation treatment planning apparatus calculates the optimum value of the leaf data (opening degree data) of the Y collimator 136 and the position data of the treatment table 133, and the computer is operated based on the calculation result, and the X collimator leaf control device, Y collimator leaf control device,
The X and Y collimator leaves, the gantry and the treatment table are driven and controlled via the gantry rotation control device, the treatment table and the long direction control device. Further, the Y collimator 136 is similar to the one shown in FIG.
As shown in FIG. 3, a description has been given of a case where the entire range of the opening degree of the first-stage collimator 135 can be shielded. However, one collimator leaf 136 </ b> B of the Y collimator 136 is driven so as to cover the entire range of the first-stage collimator 135 ( 6), and the other collimator leaf 136A may be configured to be driven so as to block the half-opening of the first-stage collimator 135 as shown in FIG. According to this embodiment as described above, the collimator leaves 136A to opening to fit the affected area I as in the above embodiment, by adjusting the 136B, housing 1 around the y-axis
32, and further, each collimator leaf 136A,
136B is sequentially moved as it is and the treatment table 133 is moved.
When the radiation is irradiated to the affected part I by setting the irradiation positions in conjunction with each other, irradiating the shaded portion A as shown in FIG. 8 will also irradiate the region B for the transmitted light, as shown in FIG. The operation and effect can be obtained. According to the present onset bright As described above, according to the present invention, release
The angle of incidence of the ray on the affected area changes, and it differs from the affected area.
It is possible to provide a radiation therapy apparatus capable of dispersing the irradiation dose to normal tissues by irradiating from normal directions and suppressing the exposure dose to normal tissues.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view showing an embodiment of the radiotherapy apparatus of the present invention. FIG. 2 is a side view showing the operation of the collimator of the radiotherapy apparatus shown in FIG. FIG. 3 is another side view showing the operation of the collimator of the radiation therapy apparatus shown in FIG. FIG. 4 is an explanatory diagram showing a range of an affected part to be irradiated with radiation based on the operation of the radiotherapy apparatus shown in FIGS. 2 and 3; FIG. 5 is a block diagram showing a drive system of the radiotherapy apparatus shown in FIG. FIG. 6 is a view corresponding to FIG. 2 and showing still another embodiment of the radiotherapy apparatus of the present invention. FIG. 7 is a view corresponding to FIG. 3, showing still another embodiment of the radiotherapy apparatus shown in FIG. 6; FIG. 8 is an explanatory diagram showing a range of an affected area to be irradiated with radiation based on the operation of the radiotherapy apparatus shown in FIGS. 6 and 7. FIG. 9 is a side view showing another example of a conventional radiotherapy apparatus. FIG. 10 is a plan view showing a collimator of the radiation therapy apparatus shown in FIG. 9 taken out therefrom. FIG. 11 is an explanatory diagram showing a range of an affected part to which radiation is applied based on the operation of the radiation therapy apparatus shown in FIG. 9; [Description of Signs] 133 treatment table, 134 X-ray generator (irradiation unit), 1
35 First collimator, 136 Y collimator, 138
X collimator.

Continued on the front page (72) Inventor Kazuyuki Hanakawa 8-1-1, Tsukaguchi Honcho, Amagasaki-shi, Hyogo Mitsubishi Electric Corporation Communication Equipment Works (72) Inventor Seiji Funata 8-1-1, Tsukaguchi-Honcho, Amagasaki-shi, Hyogo No. 1 Mitsubishi Electric Corporation Communication Equipment Works (56) References JP-A-58-67267 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A61N 5/10

Claims (1)

(57) [Claims 1] An irradiating unit for irradiating an affected part of a patient with radiation, and X-ray radiation from this irradiating unit in an XY horizontal plane
X collimator to limit the irradiation field and orthogonal to X direction
A Y collimator for limiting the radiation field in the Y direction;
For radiation whose irradiation field is limited by X and Y collimators
Radiation therapy with a treatment table for the patient to be treated
In the apparatus, the irradiation field is moved in a vertical plane in the Y direction.
The radiation field of the Y collimator
It moves in the Y direction and scans the radiation in the Y direction.
Move in the same direction in conjunction with the movement of the Y collimator.
By this, the incident angle of the radiation to the affected area of the patient
A radiotherapy device characterized by irradiating radiation from around an affected part while changing .