JP2002325854A - Radiotherapy unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiotherapy unit which enables orientation cure without moving a treatment bed. SOLUTION: This radiotherapy unit is equipped with an arm 6 rotatable centering on the horizontal rotation axis 5 supported by a rack 2, an X-ray irradiating head 7 attached to the arm 6 to irradiate X-rays to the isocenter O1 equipped on the axis line O3 of the horizontal rotation axis 5, and a treatment bed 10 on which a patient is laid so as to match the patient's target volume with the isocenter O1. A guide means 4 to support the rack 2 rotatable centering on the vertical axis O2 passing the isocenter O1 and a rotation drive means 8 to drive and rotate the rack 2 centering on the vertical axis O2 are further equipped. Because the rack 2 is rotated centering on the vertical axis O2 passing the isocenter O1 against the treatment bed 10 fixed on the floor, the rotation center of the rack 2 usually matches the isocentric floor rotation and thereby the position accuracy of the target volume in the isocentric rotation can be greatly raised.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiotherapy apparatus having improved positional accuracy of floor rotation (isocentric floor rotation) about a vertical axis passing through an isocenter, and more particularly to a radiotherapy apparatus effective for stereotactic therapy. About.

[0002]

2. Description of the Related Art Conventionally, a radiotherapy apparatus for treating a patient by irradiating a target volume (affected part) of a patient with high-energy radiation (X-rays) is mounted on a horizontal rotation axis, and the radiation treatment apparatus is arranged around the horizontal rotation axis. A gantry having a rotating arm and an X-ray irradiating head attached to the tip of the arm and irradiating an X-ray to an isocenter located on the axis of the horizontal rotating shaft, and rotatably supporting the horizontal rotating shaft. Is fixed to the floor.

A treatment table on which a patient is placed is capable of vertical movement, front and rear movement, left and right movement, as well as pivoting about a vertical axis passing through an isocenter, and moves the treatment table relative to the gantry. Thus, the target volume of the patient placed on the treatment table is aligned with the isocenter, and the X-ray irradiation head irradiates the target volume with an X-ray treatment beam to treat the patient. In particular, in stereotaxic treatment using a radiotherapy device, the X-ray irradiation head is rotated about a horizontal rotation axis while the target volume of the patient is matched with the isocenter, and at the same time, the treatment table is centered on a vertical axis passing through the isocenter. Since the treatment is carried out by turning X and intensively irradiating X-rays from multiple directions, highly accurate positioning with respect to the target volume is indispensable.

[0004]

However, as in the conventional radiotherapy apparatus, the X-ray irradiation head is rotated about a horizontal rotation axis, and at the same time, the treatment table is rotated about a vertical axis passing through the isocenter. In the case of intensive irradiation of X-rays from multiple directions, there is a limit to improving the positional accuracy of the entire treatment table due to errors in a driving system for driving the treatment table vertically, back and forth, and left and right. Also, when the arm rotates about the horizontal rotation axis, the top of the treatment table on which the patient is placed so that the X-ray irradiation head attached to the arm does not interfere with the treatment table is overhanged to the gantry side, When the treatment table is rotated, the patient's load causes the top plate to bend up and down, causing the target volume to deviate from the isocenter, resulting in reduced treatment accuracy and the treatment table on which the patient is placed to be constantly moved during treatment. However, there are problems such as giving anxiety and discomfort to the patient.

On the other hand, a radiation therapy apparatus capable of performing stereotactic therapy without moving the treatment table has been proposed in Japanese Patent Application Laid-Open No. Hei 7-116669. The radiation treatment apparatus disclosed in the above publication is configured so that stereotactic treatment can be performed without moving a treatment table by attaching a C-shaped arm to the tip of a horizontal rotating shaft and swinging the C-shaped arm around an isocenter. Have been. However, as in the radiotherapy apparatus disclosed in the above publication, the C-arm is swung about the isocenter.
Since the mechanism for swinging the C-arm becomes complicated, the device becomes expensive and the mechanical accuracy is limited. In addition, since the size of the linear accelerator that can be mounted on the C-arm is limited, the types of energy that can be used are reduced, and as a result, there is a problem that general versatility for radiation therapy is poor.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and provides a radiotherapy apparatus capable of performing stereotactic treatment without moving a treatment table, so that the positional accuracy of isocentric bed rotation can be improved. The purpose is to improve.

[0007]

According to the present invention, there is provided a radiotherapy apparatus comprising: an arm rotatable around a horizontal rotating shaft supported by a gantry;
And X to the isocenter provided on the axis of the horizontal rotation axis.
What is claimed is: 1. A radiotherapy apparatus comprising: an X-ray irradiation head for irradiating a beam; and a treatment table on which a patient is placed so that a target volume of the patient to be treated coincides with the isocenter. Guide means for supporting the gantry so as to be pivotable about a vertical axis passing through the isocenter, and turning drive means for pivotally driving the gantry about the vertical axis.

[0008] With the above configuration, the gantry can be turned around the vertical axis passing through the isocenter with respect to the treatment table fixed to the floor, and the X-ray irradiation head can irradiate the target volume of the patient with X-rays. The center of rotation of the gantry always coincides with the isocentric floor rotation, which can dramatically increase the positional accuracy of the target volume in the isocentric floor rotation, thereby improving the accuracy of the stereotactic radiotherapy. be able to. In addition, since the treatment table does not move during treatment, even if the top of the treatment table is overhanging, the position of the target volume does not deviate from the isocenter even if the top of the treatment table is bent, which enables highly accurate treatment And there is no need to worry about giving patients anxiety or discomfort during treatment. Furthermore, the configuration of the guide means and the rotation driving means is simpler than that of the conventional radiation therapy apparatus which swings the C-arm, so that the cost of the radiation therapy apparatus can be reduced and the size of the linear accelerator mounted on the arm can be reduced. And therefore, the types of energy that can be used are increased, thereby improving the versatility for radiation therapy in general.

In order to achieve the above-mentioned object, a radiotherapy apparatus according to the present invention is characterized in that the guide means is constituted by a guide rail laid on a floor on which a gantry is installed and formed in an arc shape centered on a vertical axis. is there.

[0010] According to the above configuration, the gantry is supported by the guide rails laid on the floor without bending, and the gantry is turned. Therefore, vibration and the like do not occur during the turning operation. By laying the guide rails on the floor so that the center of rotation of the gantry coincides with the vertical axis passing through the isocenter, the center of gyration of the gantry can be made to coincide with the isocenter, so that the radiation therapy apparatus Installation work can be performed easily and with high accuracy.

In order to achieve the above object, the radiation therapy apparatus according to the present invention is characterized in that the rotation driving means is laid on the floor on which the gantry is installed, and is formed in an arc shape centered on a vertical axis, and mounted on the gantry. Rotation drive by the rotation drive source
And a pinion meshed with the rack.

According to the above configuration, since the rotary drive source only needs to be installed in a small space in the gantry, the size of the treatment apparatus can be reduced, and the swing drive means with high swing accuracy can be obtained at low cost.

In order to achieve the above object, a radiation therapy apparatus according to the present invention is configured such that a treatment table can be freely moved and adjusted around a vertical axis in a turning direction.

According to the above configuration, since the target volume position can be changed with respect to the isocenter, more effective radiotherapy can be performed.

[0015]

Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a side view of the radiotherapy apparatus, and FIG. 2 is a plan view of the same. A gantry 2 containing a microtron 1 for generating X-rays is installed on a guide means 4 laid on a floor 3. Guide means 4 plural arcuate guide rail 4a about a vertical axis 0 ₂ at intervals in the radial direction through the isocenter 0 _1, for example, in laying configurations on two floor 3, the vertical axis 0 ₂ the guide rail 4a such that the gantry 2 to pivot with high precision around the is formed by a LM guide. A plurality of support members 4b are slidably supported on each guide rail 4a, and a box-shaped gantry 2 is installed on these support members 4b so as to be reciprocally movable along the guide rails 4a.

A horizontal rotating shaft 5 is rotatably supported in the gantry 2, and a vertical portion 6a of an arm 6 formed substantially in an inverted L-shape at the tip of the horizontal rotating shaft 5 protruding from the gantry 2.
Is installed. Arm 6 is freely rotated around a horizontal shaft 5, the horizontal portion 6b of the arm 6, the X-rays generated by the microtron 1, provided on the center axis 0 ₃ of the horizontal shaft 5 X-ray irradiation head 7 for irradiating the isocenter 0 ₁ is attached.

Further the bottom of the pedestal 2, the turning drive means 8 for turning the frame 2 about a vertical axis 0 ₂ are provided. The turning drive means 8 includes a rotary drive source 8a composed of an electric motor.
A pinion 8b rotated by a rotation drive source 8a;
The guide rail 4a have been more configuration and installed rack 8c between the rack 8c is similar to the guide rails 4a, with is formed in a arcuate shape about the vertical axis 0 _2, the pinion 8b on the rack 8c Are engaged.

On the other hand, it is attached to the horizontal portion 6b of the arm 6.
A radiation source 7a is provided in the X-ray irradiation head 7, and a radiation source 7a is provided.
Beam axis 0 of X-ray emitted from source 7a₄And horizontal rotation axis
5 center axis 0₃Intersection with isocenter 0₁Tona
The target volume of the patient placed on the couch 10
Isocenter 0₁On the floor 3 to match with high precision
A table 10 is provided. Beam axis 0₄The direction of
Center axis 0 of horizontal rotating shaft 5₃Of arm 6 around
Roll and vertical axis 0₂Of the frame 2 around the
The vertical portion 6a of the arm 6 varies over multiple dimensions.
Beam axis 0 only when is perpendicular to the floor ₄Is the vertical axis
0₂Is to be matched. The treatment table 10 is on the floor 3
And a box-shaped support 10a fixed on the support 10a
Installed horizontally, and up and down, front and back by drive system not shown
And a top plate 10b that can be moved and adjusted in the left-right direction.
When the arm 6 rotates about the horizontal rotation axis 5,
The X-ray irradiation head 7 attached to the
Make sure that the top of the top plate 10b is
Bahang has been.

Next, the operation of the radiotherapy apparatus configured as described above for stereotactic treatment of a patient will be described. Floor 3
In a state of lying the patient on the top plate 10b of the treatment table 10 that is fixed to the upper mounted as shown in FIG. 1, the top plate 10 by a drive system such that the target volume of the patient is consistent with the isocenter 0 ₁
b up and down, back and forth, when positioned by moving adjusting the lateral direction, to lock the drive system, also the platform 2 is pivoted to the required position about the vertical axis 0 ₂ by turning drive means 8 for locking. Next, in a state where the X-ray is generated by operating the microtron 1, the arm 6 is rotated within a desired range of 360 degrees around the horizontal rotation axis 5, and then the microtron 1 is stopped. while interrupting the generation of X-rays, the gantry 2 is pivoted to the next desired position about the vertical axis 0 ₂ by turning drive means 8 for locking. Thereafter, while the microtron 1 is operated to generate X-rays, the arm 6 is rotated within a desired rotation range of 360 degrees around the horizontal rotation axis 5 and this procedure is repeated as many times as necessary. . This X-ray therapy beam irradiated from the X-ray emitting head 7 is intensively irradiated to the target volume of a patient position from the multi-directional three-dimensional isocenter 0 _1, is carried out treatment with high-energy radiation You.

Since the treatment table 10 does not move during the treatment,
Regardless of the position of the gantry 2 on the guide rail 4a, the center of rotation of the gantry 2 and the isocentric floor rotation (vertical axis 0
₂ ) is always the same, whereby the positional accuracy of the target volume in the rotation of the isocentric bed can be drastically increased, so that the treatment accuracy can be improved.

In the above embodiment, the case where the treatment table 10 is fixed on the floor 3 has been described.
As shown in FIG. 5, the treatment table 10 may be adjusted so as to be pivotable about an isocentric bed rotation axis. That is, changing the position of the patient according to the position of the target volume of the patient may enable more effective treatment. Therefore, in the modification shown in FIGS. 3 and 4, the same guide means 4 and turning drive means 8 as those on the gantry 2 side are also provided on the treatment table 10 side, and the vertical axis 0 is provided.
_The treatment table 10 can be pivotally adjusted about the center _3. After the adjustment, the treatment table 10 is fixed to the floor 3 by a lock means or the like, so that the target in the isocentric bed rotation is the same as in the above embodiment. The positional accuracy of the volume can be improved.

In the above embodiment, the turning drive means 8
Is composed of a rack 8c and a pinion 8b, and a rotary drive source 8a for driving the pinion 8b.
a and a chain engaged with this sprocket, or the gantry 2 may be directly driven by an actuator.

[0023]

According to the present invention, as described in detail above, a treatment table on which a patient is placed is fixed to the floor, and guide means for supporting the gantry between the gantry and the floor so as to be pivotable about a vertical axis passing through an isocenter. And a swing driving means for swinging and driving the gantry about the vertical axis, the gantry is swiveled about a vertical axis passing through the isocenter with respect to the treatment table fixed to the floor, and the X-ray irradiation head In order to irradiate the patient's target volume with X-rays, the center of rotation of the gantry and the rotation of the isocentric floor always coincide with each other, so that the positional accuracy of the target volume in the rotation of the isocentric floor can be dramatically improved. In addition, the accuracy of radiation treatment can be improved.

Further, since the treatment table does not move during the treatment, even if the table of the treatment table is overhang, the position of the target volume is not shifted from the isocenter due to the bending of the table, thereby providing high accuracy. In addition to being able to treat, there is no need to worry about giving patients anxiety or discomfort during treatment.
Compared to conventional radiation therapy devices that swing the mold arm,
Since the configuration of the guide means and the turning drive means is simplified, the cost of the radiation therapy apparatus can be reduced, and the size of the linear accelerator mounted on the arm is less likely to be limited.
More types of energy are available, which increases versatility for radiation therapy in general.

Further, since the guide means is constituted by guide rails laid on the floor on which the gantry is installed and formed in an arc shape centered on the vertical axis, the gantry is provided by the guide rail laid on the floor without bending. Is supported and pivoted, so that no vibration or the like is generated during the pivoting operation, thereby making it possible to extremely reduce the position fluctuation during the pivoting of the gantry, and to set the pivoting center of the gantry with the vertical axis passing through the isocenter. By laying the guide rails on the floor so that they coincide with each other, the center of rotation of the gantry can be made to coincide with the isocenter, so that the operation of installing the radiation therapy apparatus can be performed easily and with high accuracy.

[0026] The turning drive means is laid on the floor on which the gantry is installed and is formed in an arc shape centered on a vertical axis, and is rotatably driven by a rotary drive source installed on the gantry, and meshes with the rack. Since the rotary drive source only needs to be installed in a small space in the gantry, it is possible to reduce the size of the treatment apparatus, and to obtain a high-precision turning drive unit at low cost, If the treatment table can be freely moved and adjusted about the vertical axis in the turning direction, the target volume position can be changed with respect to the isocenter, so that more effective radiation treatment can be performed.

[Brief description of the drawings]

FIG. 1 is a side view of a radiotherapy apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of the radiotherapy apparatus according to the embodiment of the present invention.

FIG. 3 is a side view showing a modified example of the radiotherapy apparatus according to the embodiment of the present invention.

FIG. 4 is a plan view showing a modification of the radiotherapy apparatus according to the embodiment of the present invention.

[Explanation of symbols]

 2 gantry 4 guide means 4a guide rail 4b support member 5 horizontal rotating shaft 6 arm 6a vertical part 6b horizontal part 7 X-ray irradiation head 7a radiation source 8 rotation drive means 8a rotation drive source 8b pinion 8c rack 10 treatment table 10a support table 10b Top plate O1 Isocenter O2 Vertical axis O3 Axis of horizontal rotation axis 04 Beam axis

Claims (4)

[Claims] 1. An X-ray irradiator for irradiating an X-ray to an arm rotatable about a horizontal rotation shaft supported by a gantry and an isocenter attached to the arm and provided on an axis of the horizontal rotation shaft. A head and a radiation treatment apparatus including a treatment table on which a patient is placed so that a target volume of a patient to be treated coincides with the isocenter, wherein the treatment table is fixed to a floor, and between the gantry and the floor, A radiation treatment apparatus, comprising: a guide means for pivotally supporting the gantry about a vertical axis passing through the isocenter; and a slewing drive means for slewing the gantry about the vertical axis. 2. The radiotherapy apparatus according to claim 1, wherein the guide means is constituted by a guide rail laid on a floor on which the gantry is installed and formed in an arc shape centered on the vertical axis. . 3. The turning drive means is laid on a floor on which the gantry is installed, and is formed in a circular arc shape around the vertical axis, and is rotationally driven by a rotary drive source installed on the gantry. 2. The radiotherapy apparatus according to claim 1, further comprising a pinion meshed with the rack. 4. The radiotherapy apparatus according to claim 1, wherein the treatment table can be freely moved and adjusted in a turning direction about the vertical axis.