JP2006021046A - Radiotherapy apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To monitor a state of a therapeutic field on a real time basis without hindering a radioactive ray irradiating head by a real time imager operating in association with the radioactive ray irradiating head even when the therapeutic field in radiotherapy moves. <P>SOLUTION: This radiotherapy apparatus having the radioactive ray irradiating head 10, an X-ray source 77 and a sensor array 78 is used. Here, the radioactive ray irradiating head 10 irradiates a diseased part 5 of a patient 4 with a therapeutic radioactive ray 3a. The X-ray source 77 irradiates the diseased part 5 of the patient 4 with a diagnostic X-ray 3b. The sensor array 78 outputs a transmitted X-ray as diagnostic image data by detecting the transmitted X-ray of the diagnostic X-ray 3b passed through the patient 4. The sensor array 78 and the X-ray source 77 move in association with the movement of the radioactive ray irradiating head 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a radiotherapy device, and more particularly to a radiotherapy device used for stereotactic radiotherapy.

Radiotherapy devices for treating cancer and tumors using radiation are known. Radiosurgery treatment devices, linac treatment devices, and the like are known as three-dimensional irradiation radiation treatment devices that irradiate in a stereotactic orbit (see Non-Patent Documents 1 and 2).
Here, stereotactic multi-orbital irradiation is a radiotherapy method that increases the therapeutic effect by irradiating a small lesion intensively with radiation from multiple directions and minimizes the exposure dose of surrounding tissues. It is effective in treating primary benign brain tumors, single metastatic brain tumors of 3 cm or less in size, small lesions in the brain such as skull base metastases that are difficult to operate, or arterial or venous malformations. .

The radiosurgery treatment apparatus irradiates a narrow radiation beam intensively to a specific small area with particularly high accuracy from one or a plurality of radiation irradiation units fixed to the treatment apparatus. A gamma ray source or linac is used as the radiation irradiation unit.
In the radiosurgery treatment device, an affected part such as a patient's skull or its peripheral part is mechanically fixed using a precision positioning / affected part fixing jig, which is a stereotaxic radiation fixing tool. Then, using this frame as a coordinate reference jig for positioning, a diagnostic image is acquired using X-ray CT (Computed Tomography), MRI, or the like, and the exact position and shape of the affected part are determined. Then, the patient is mechanically fixed in this frame as it is to an irradiation apparatus composed of one or a plurality of irradiation units and a collimating mechanism that collimates them and concentrates therapeutic radiation in a small area of the space. . As a result, the irradiation field is mechanically precisely matched to the small area, and precise localization irradiation is performed.

  In the radiosurgery treatment apparatus, therapeutic radiation (X-rays) is emitted based on a diagnostic image taken in advance. That is, the diagnostic X-ray system (X-ray generator-image detector) for observing the affected area in real time is not provided, and radiation is not irradiated while observing the affected area in real time.

  In the linac treatment apparatus, a large gantry is rotated 360 degrees around one axis parallel to the installation surface, thereby performing isocentric irradiation treatment. In addition to this, various irradiations are possible by adding two-dimensional movement and rotation in the vertical and horizontal planes of the treatment bed and in the horizontal plane.

  The linac treatment device cannot perform high-speed position control. Therefore, real-time follow-up irradiation to a therapeutic field that moves at high speed, such as movement by heartbeat, is not possible. Further, as a means for monitoring the irradiation field during irradiation, linacography using therapeutic X-ray transmission rays is used. Since therapeutic X-rays are highly transmissive and have many scattered rays, the image quality for real-time monitoring of the irradiation field is not high.

In the linac treatment device, a marker attached to the affected area is tracked by a diagnostic X-ray system, the position of the affected area is estimated, and radiation is emitted when the estimated position and the irradiation field overlap (moving object tracking) Irradiation). Here, the diagnostic X-ray system includes a diagnostic X-ray generator attached to the ceiling and an image detector attached to the lower part of the linac treatment apparatus. In this method, the position of the actual affected area is grasped in real time, and radiation is not irradiated while tracking so that the position of the actual affected area and the irradiation field overlap.
Since the X-ray generator is fixed to the ceiling, the distance from the image detector is large. Further, due to the rotation of the main body of the linac treatment apparatus, the image detector may enter the shadow of the main body, and the diagnostic X-ray from the X-ray generator may not reach the image detector. In preparation for this, an X-ray generator is frequently attached to the ceiling, and two usable units are selected from the two. Furthermore, the image detector is installed in a region where a transmitted beam (a treatment beam transmitted through the subject) and a scattered beam (a treatment beam scattered by the subject) are directed.

  As related techniques, Japanese Patent Publication No. Hei 6-502330 (International Application No .: PCT / US91 / 07696) and Japanese Patent Publication No. 8-504347 (International Application No .: PCT / US93 / 11872) are disclosed for stereotaxic surgery. An apparatus and method is disclosed.

One of the stereotaxic surgical apparatuses (see Patent Documents 1 and 2) is an apparatus that drives an electronic linac in an isocentric manner, and includes an electronic linac at the tip of an industrial general-purpose robot arm. This device is capable of essentially non-isocentric irradiation treatment due to the free movement capability of the 6-DOF robot arm.
The exact shape and position of the affected area can be determined in advance by using X-ray CT, MRI, etc. on landmark body tissues such as the skull and chest and markers embedded near the affected area (example: small gold plate embedded in the affected area). Associate and determine. The stereotaxic surgical device uses the two diagnostic X-ray systems with different lines of sight during treatment irradiation to monitor the movement of the landmarks and correct the aim, while accurately irradiating the treatment beam. Do. It takes 1-2 seconds for the sighting correction time and 0.5 seconds to 1 second for the irradiation time.

  Of these two diagnostic X-ray systems, the X-ray generator is firmly fixed to the ceiling. An image receiver (image detector) that receives transmitted X-rays is disposed in the lower part of the bed. That is, the X-ray generator has a large distance from the image detector. Further, due to the rotation of the main body of the linac treatment apparatus, the image detector may enter the shadow of the main body, and the diagnostic X-ray from the X-ray generator may not reach the image detector. On the other hand, the image receiver is on the opposite side of the treatment beam irradiation device with the bed interposed therebetween. That is, the image receiver is installed in a region where a transmitted beam (a treatment beam transmitted through the subject) and a scattered beam (a treatment beam scattered by the subject) are directed.

Another one of the stereotaxic surgical devices (see Patent Documents 1 and 2) is a device that drives an electronic linac along a gantry, and two diagnostic X-ray systems (X-ray generators) in the gantry. -An image receiver) and an electronic linac. Three-dimensional irradiation can be performed by rotating the electronic linac around one axis in the vertical direction as well as around one axis in the horizontal direction. However, the irradiation method is isocentric.
Also in this stereotaxic surgical apparatus, the exact shape and position of the affected area are determined in advance in association with landmark-like body tissues and markers embedded in the vicinity of the affected area by X-ray CT or the like. Then, at the time of treatment irradiation, two diagnostic X-ray systems having different lines of sight are used to monitor the movement of the landmark and correct the aim, while performing precise irradiation of the treatment beam. It takes 1-2 seconds for the sighting correction time and 0.5 seconds to 1 second for the irradiation time.

  The two diagnostic X-ray systems are installed in a gantry in which an electronic linac is installed. Similarly, the X-ray generator is installed in the gantry on the electronic linac side away from the electronic linac. The image receiver is installed in a gantry on the opposite side of the X-ray generator with the subject interposed therebetween. That is, the image receiver is installed in a region where a transmitted beam (a treatment beam transmitted through the subject) and a scattered beam (a treatment beam scattered by the subject) are directed.

In general, the affected area of a patient moves during treatment. In particular, the irradiation target such as a tumor is constantly moving from the neck to the bottom under the influence of organ movement and state such as breathing, heartbeat, peristalsis, and urine volume in the bladder. For example, just by lying down, the body gradually flattens. In addition, although periodic movements such as breathing and heartbeat are periodic, the movement of each organ accompanying the movement does not always follow the same path.
If the movement of the irradiation target is accurately captured in real time, the heartbeat, which is one of the fastest movements, is 1 to 2 times / second. Therefore, in order to obtain an accurate diagnostic image in real time, it is said that an image capturing technique of about 30 images / second is required. If the irradiation target is accurately tracked in real time and radiation is to be irradiated, it is necessary to accurately direct the radiation irradiation head to the irradiation target every 1/30 seconds. Further, regarding tracking, in order to obtain a high-quality diagnostic image, it is important to eliminate the influence of therapeutic radiation (X-rays) on the image detector of the diagnostic X-ray system.

  A technique that can monitor the state of the treatment field in real time is desired. There is a need for a technique that can eliminate the effects of therapeutic radiation (X-rays) on the image detector of a diagnostic X-ray system. There is a need for a technique capable of irradiating radiation while following the treatment field even when the radiation treatment field moves. A technique capable of reducing the burden of radiation irradiation on a patient while enhancing the therapeutic effect is desired.

Takehiro Saijo, “Radiation Therapy Physics”, Bunkodo Co., Ltd., February 26, 2001, p. 95-153 Masahiro Hiraoka, Keisuke Sakurai, edited by Toshihiko Inoue, “Radiation Therapy Manual”, Chugai Medical Co., Ltd., April 10, 2001, p. 19-63 Japanese translation of PCT publication No. 6-502330 (International application number: PCT / US91 / 07696) (pages 5-6, FIGS. 1-3) Japanese translation of PCT publication No. 8-504347 (International application number: PCT / US93 / 11872) (pages 20 to 26, FIGS. 5 to 9)

  Accordingly, an object of the present invention is to provide a radiotherapy apparatus capable of monitoring the state of a treatment field in real time even during radiation treatment.

  Another object of the present invention is to provide a radiotherapy apparatus capable of eliminating the influence of therapeutic radiation (X-rays) on the image detector of a diagnostic X-ray system.

  Still another object of the present invention is to provide a radiotherapy apparatus capable of irradiating radiation while following a treatment field even when the treatment field in radiation therapy moves.

  Another object of the present invention is to provide a radiotherapy apparatus capable of performing radiation irradiation not only by irradiation around one rotation axis or isocentric irradiation but also by quickly aiming from a wide area. It is.

  Still another object of the present invention is to provide a radiotherapy apparatus capable of accurately irradiating radiation and reducing the burden on the patient while enhancing the therapeutic effect.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the embodiments of the present invention. These numbers and symbols are added to clarify the correspondence between the description of [Claims] and [Embodiments of the Invention]. However, these numbers and symbols should not be used for the interpretation of the technical scope of the invention described in [Claims].

Therefore, in order to solve the above problems, the radiation therapy apparatus of the present invention includes a radiation irradiation head (10), an X-ray source (37, 77), and a sensor array (38, 78).
The radiation irradiation head (10) irradiates the therapeutic field (3a) to the treatment field (5) of the subject (4). The X-ray source (37, 77) irradiates the treatment field (5) of the subject (4) with diagnostic X-rays (3b). The sensor arrays (38, 78) detect the transmitted X-rays of the diagnostic X-rays (3b) that have passed through the subject (4) and output them as diagnostic image data.
The sensor array (38, 78) moves in conjunction with the movement of the radiation irradiation head (10).
Due to the interlocked operation of the sensor array (38, 78) and the radiation irradiation head (10), the sensor array (38, 78) can detect transmitted X-rays without being shaded by the radiation irradiation head (10). it can. Further, the radiation irradiation head (10) does not receive strong radiation (X-rays). However, in the interlocking, when the sensor array (38, 78) and the radiation irradiation head (10) move in the same direction with the same distance or the same angle, or when they move so as not to interfere with each other according to a predetermined rule, A case where the other operates when a predetermined condition is satisfied based on one operation is included. The therapeutic radiation (3a) includes X-rays.

In the radiotherapy apparatus of the present invention, the X-ray source (37, 77) moves in conjunction with the movement of the sensor array (38, 78).
The sensor array (38, 78) transmits the transmitted X-rays at an appropriate position by the operation of the sensor array (38, 78) linked to the radiation irradiation head (10) and the X-ray source (37, 77). Can receive light.

In the radiotherapy apparatus of the present invention, the sensor array (38, 78) is provided in the vicinity of the radiation irradiation head (10).
Since it is provided in the vicinity, the sensor array (38, 78) can be easily interlocked with the radiation irradiation head (10). Further, the radiation irradiation head (10) does not receive strong radiation (X-rays).

In the radiotherapy apparatus of the present invention, sensor arrays (38, 78) are provided on both sides of the radiation irradiation head (10).
Since it is arranged in a balanced manner on both sides, not on one side, it is easy to interlock with the radiation irradiation head (10). Moreover, it is structurally stable.

Further, the radiotherapy apparatus of the present invention has a distance between each of the X-ray source (37, 77) and sensor array (38, 78) and the isocenter (5a) such that the radiation irradiation head (10), the isocenter (5a) and Less than the distance.
Since the X-ray source (37, 77) and the sensor array (38, 78) capture a diagnostic image near the subject (4), the image quality of the captured image is improved. Further, the X-ray source (37, 77) and sensor array (38, 78) and the radiation irradiation head (10) hardly interfere mechanically.

In the radiotherapy apparatus of the present invention, the X-ray source (37, 77) and the sensor array (38, 78) are in a symmetrical position with respect to the isocenter (5a).
Since it is in a symmetrical position, a good diagnostic image of the subject (4) can be obtained.

In the radiotherapy apparatus of the present invention, the radiation irradiation head (10) can be any of a C-type gantry (89), an Ω-type gantry (9), an L-type gantry (not shown), and a robot arm (not shown). It is provided to be movable.
The C-type gantry (89) and the Ω-type gantry (9) include a trajectory (not shown) through which the radiation irradiation head (10) moves. An L-type gantry (not shown) and a robot arm (not shown) move while holding the radiation irradiation head (10).
The configuration of each of the above items can be applied regardless of the type of gantry or robot arm that holds the radiation irradiation head (10), the X-ray generator (37, 77), or the sensor array (38, 78).

Further, in the radiotherapy apparatus of the present invention, the radiation irradiation head (10) is movably provided in an O-type gantry (69) having a trajectory along which the radiation irradiation head (10) moves.
The O-type gantry (69) has a stable gantry strength and structure, and can operate with higher accuracy. The radiation irradiation head (10), the X-ray generator (37, 77) and the sensor array (38, 78) can be arranged in a balanced manner.

Furthermore, in the radiotherapy apparatus of the present invention, the X-ray source (not shown) and the sensor array are provided inside the ring of the O-type gantry.
Each component can be provided inside the annular gantry, and there is little deviation in weight, and the structure is stable.

Furthermore, the radiotherapy apparatus of the present invention further comprises a control unit (80) and an image processing unit (31). However, the diagnostic image of the treatment field (5) is generated based on the diagnostic image data.
The radiation irradiation head (10) is movably connected to the O-type gantry (69) and includes a head swing mechanism (131, 132). Here, the head swing mechanism (131, 132) is arranged so that the therapeutic radiation (3a) emitted from the radiation irradiation head (10) follows the movement of the treatment field (5). Swing.
Based on the diagnostic image, the position of the radiation irradiation head (10), and the swinging state of the radiation irradiation head (10), the control unit (80) irradiates the irradiation field (5 ′) of the radiation irradiation head (10). Controls the head swing mechanism (131, 132) so as to track the treatment field (5). Then, after the head swing mechanism (131, 132) is controlled, the radiation irradiation head (10) is controlled so as to irradiate the therapeutic radiation (3a) from the radiation irradiation head (10).
The head swing mechanism (131, 132) allows the radiation irradiation head (10) to irradiate the treatment radiation (3a) quickly and accurately to the calculated position of the affected part (5).

Furthermore, in the radiotherapy apparatus of the present invention, the control unit (80) coordinates the treatment field (5) in the diagnostic image based on the pattern designated in advance on the diagnostic image indicating the treatment field (5). The first coordinates (X, Y, Z) are calculated. Further, based on the position of the radiation irradiation head (10) and the swinging state of the radiation irradiation head (10), second coordinates (x, y, z) as coordinates of the irradiation field (5 ′) are calculated. Then, based on the first coordinate (X, Y, Z) and the second coordinate (x, y, z), the head swing mechanism so that the treatment field (5) is included in the irradiation field (5 ′). (131, 132) is controlled.
The position of the treatment field (5) that changes from moment to moment can be grasped using diagnostic images acquired in real time, and tracking can be performed with an appropriate radiation irradiation head (10), so that the affected area (5) can be accurately detected. It is possible to irradiate various therapeutic radiation (3a).

Furthermore, in the radiotherapy apparatus of the present invention, the control unit (80) controls the head swing mechanism (131, 132) and the radiation irradiation head (10) at predetermined time intervals.
By determining the time interval, it is possible to appropriately track according to the speed of movement of the affected part (5).

Furthermore, in the radiotherapy apparatus of the present invention, the head swing mechanism (131, 132) swings the radiation irradiation head (10) around each of two axes (S1, S2) orthogonal to each other.
By using the gimbal mechanism, the irradiation field (5 ′) of the radiation irradiation head (10) can surely capture a predetermined range.

Furthermore, the radiotherapy apparatus of the present invention further includes a head circumferential movement mechanism (70) for moving the radiation irradiation head (10) along the O-type gantry (69).
The radiation irradiation head (10) can rotate 360 ° along the O-type gantry (69).

Furthermore, the radiotherapy apparatus of the present invention further includes a gantry rotation mechanism (72) for rotating the O-type gantry (69) about the vertical axis (J1).
The position of the radiation irradiation head (10) can be moved in a spherical shape by an O-type gantry (69) rotating around the vertical axis (J1), and therapeutic radiation (3a) can be delivered to the subject (4) from any angle. Can be irradiated.

Furthermore, the radiotherapy apparatus of the present invention further comprises a microwave generator (20) and a waveguide (51).
However, the microwave generator (20) generates microwaves. The waveguide (51) has one end connected to the microwave generator (20) and the other end connected to the radiation irradiation head (10), and guides the microwave to the radiation irradiation head (10).
The microwave generator (20) is disposed outside the radiation irradiation head (10), and the mass and size of the radiation irradiation head (10) can be reduced.

Furthermore, in the radiotherapy apparatus of the present invention, the microwave belongs to the C band.
The radiation irradiation head (10) includes an acceleration tube (110) that accelerates an electron beam with the microwave.
Since a high-frequency C-band macro wave is used, the size of the acceleration tube (110) can be reduced, and the mass and size of the radiation irradiation head (10) can be reduced.

Furthermore, in the radiotherapy apparatus of the present invention, the microwave belongs to the X band.
The radiation irradiation head (10) includes an acceleration tube (110) that accelerates an electron beam with the microwave.
Since the high-frequency X-band macro wave is used, the size of the acceleration tube (110) can be reduced, and the mass and size of the radiation irradiation head (10) can be reduced.

  The radiotherapy apparatus of the present invention is in addition to a mechanism (9/28, 69/72, 89/72) for moving and positioning the radiation irradiation head (10) in an isocentric direction in one or two axes. By adding a mechanism (131, 132) for rotating the radiation irradiation head (10) by a small angle in the direction of one axis or two axes (swinging), it becomes possible to perform pseudo non-isocentric irradiation. The non-isocentric component required for handling the irregular irradiation field (5 ') and following the movement of the irradiation field (5') is 50 mm or less in the irradiation field (5 '). The distance SAD between the radiation source and the isocentric irradiation field (5 ') is 80 cm to 100 cm in the case of a normal electronic linac. When SAD is 100 cm, the small-angle rotational motion (swing) angle required for the radiation irradiation head (10) is about 3 degrees. The change in SAD due to this motion is 0.2%, and the change in the beam diameter of the therapeutic radiation (3a) due to the change in SAD is in a negligible range. Further, by devising the mechanism to perform this rotational movement about the inertia center of the radiation irradiation head (10), the burden on the drive mechanism can be reduced. By driving a dummy weight having the same moment as the moment around the rotation axis of the radiation irradiation head (10) in the opposite direction to the rotation direction, it is possible to cancel the reaction force associated with the small-angle rotation motion (swing).

  The irradiation head (10) and the imager (10) are arranged so that the imager (30) having the X-ray generator (37, 77) and the image detector (38, 78) and the irradiation head (10) do not mechanically interfere with each other. 30) operate in conjunction with each other. Since the imager (30) captures a diagnostic image near the subject (4), the image quality of the captured image is improved. The imager (30) and the mechanism have a common position coordinate. In addition, the timing of image capture of the imager (30) and the irradiation timing of the therapeutic radiation (3a) are controlled in a time-sharing manner, so that the influence of the therapeutic radiation (3a) on the imager (30) is affected. It is possible to monitor the image of the treatment field in real time even during treatment irradiation. At that time, since the image detectors (38, 78) are on the radiation irradiation head (10) side, they are not affected by the therapeutic radiation (3a) of the radiation irradiation head (10).

  Follow-up irradiation to the moving treatment field by tracking the image of the treatment field image in the monitor image (display) with an appropriate algorithm and controlling the small-angle rotational motion (swing) following this. Treatment becomes possible.

  Furthermore, by providing an appropriate man-machine interface and safety mechanism, it is possible to realize a radiotherapy apparatus with high safety and reliability.

  In the radiotherapy apparatus of the present invention, the X-ray head (radiation irradiation head) is obstructed by a real-time imager (X-ray system) operating in conjunction with the X-ray head (radiation irradiation head) even during radiation irradiation treatment. It is possible to monitor the state of the treatment field in real time without doing so.

  Hereinafter, embodiments of a radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.

Example 1
A first embodiment of a radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.
1 to 2 are a front view and a cross-sectional view showing the configuration of the first embodiment of the radiation therapy apparatus according to the present invention. Some parts are omitted from the figure. A coordinate 200 indicates a three-dimensional orthogonal coordinate having the X axis, the Y axis, and the Z axis in FIGS.
The radiotherapy apparatus 6A includes a therapeutic bed system 7, an X-ray head 10, a support frame 67-1, a support frame 67-2, an O-type gantry 69, a driven waveguide system 61, a microwave generator 20, and a real-time imager. 74 is provided.

The therapeutic bed system 7 includes a bed driving system 7-1, a therapeutic bed 7-2, and a patient fixing device 7-3.
The treatment bed 7-2 carries the patient 4 to be subjected to radiation therapy and moves to a predetermined position in the apparatus. The patient fixing device 7-3 fixes the patient 4 to the treatment bed 7-2. The bed driving system 7-1 includes a therapeutic bed 7-2 by a built-in driving mechanism.
Can be moved in the three-axis directions of the X axis, the Y axis, and the Z axis. Then, the bed driving system 7-1 performs treatment so that the affected area 5 serving as the treatment field is located at the isocenter 5a based on the captured image data of the real-time imager (74) under the control of the system controller 80 (described later). The position of the bed 7-2 can be adjusted. For the treatment bed 7-2 and the patient fixing device 7-3, materials and shapes suitable for the use of the diagnostic imaging device of the real-time imager (74) are selected.

  The O-type gantry 69 includes a ring circumferential movement mechanism 70, O-type drive rings 71-1 and 71-2, a gantry rotation mechanism 72, and an upper support mechanism 82.

  The O-type gantry 69 (main body) is a ring which is provided so as to surround the periphery of the treatment bed 7-2 and has an annular tube having a rectangular cross section. It is installed on the gantry rotating mechanism 72 so as to stand upright with respect to the horizontal plane (XY plane). Then, the treatment bed 7-2 and the X-ray head 10 are arranged so that the center of the circle is the isocenter 5a.

  The gantry rotating mechanism 72 includes a base portion 72-1, a rotating portion 72-2, and a driving portion 72-3. The base portion 72-1 is fixedly provided on the bottom surface (floor surface or the like). The rotating unit 72-2 is rotatably provided on the base unit 72-1, and holds the O-type gantry 69 in a fixed manner. The driving unit 72-3 rotates the rotating unit 72-2 (and the O-type gantry 69 thereon). That is, the mounted O-type gantry 69 is rotated around the first rotation axis J1 that is an axis in the vertical direction (Z-axis direction) as indicated by I1 in the figure. However, the first rotation axis J1 overlaps the diameter of the circle formed by the O-type gantry 69 and passes through the center of the circle (isocenter 5a).

The O-type drive rings 71-1 and 71-2 are rings having an inner diameter and an outer diameter substantially similar to those of the O-type gantry 69. Each of them is coaxial and parallel to a circle formed by the O-type gantry 69, and is provided so as to be rotatable with respect to the O-type gantry 69 so as to sandwich the O-type gantry 69. The O-type gantry 69 is rotated with respect to the O-type gantry 69 around a second rotation axis J2 perpendicular to the plane formed by the O-type gantry 69, perpendicular to the first rotation axis J1 and passing through the isocenter 5a, as indicated by I2. At this time, the O-type drive rings 71-1 and 71-2 rotate integrally through the ring circumferential movement mechanism 70.
The ring circumferential movement mechanism 70 is fixedly connected to the O-type drive rings 71-1 and 71-2 so as to be movable with the O-type gantry 69. The O-type drive rings 71-1 and 71-2 are moved around along the O-type gantry 69 as indicated by I2 in the figure. The ring orbiting movement mechanism 70 may include O-type drive rings 71-1 and 71-2. The ring orbiting movement mechanism 70 can employ a rack and pinion method, a belt method, or the like.

  The upper support mechanism 82 includes a base portion 82-1 and a rotating portion 82-2. The base part 82-1 is fixedly provided on the upper part (ceiling or the like). The rotating portion 82-2 is rotatably provided below the base portion 82-1, and holds the O-type gantry 69 from above. That is, the rotation of the gantry rotation mechanism 72 around the first rotation axis J1 is supported by the upper portion of the O-type gantry 69.

The O-type gantry 69 can rotate 160 ° around the first rotation axis J1. Also, the O-type drive rings 71-1 and 71-2 can rotate 360 ° on the O-type gantry 69. That is, the ones fixed to the O-type drive rings 71-1 and 71-2 (X-ray head 10 and others (described later)) have an eight-nineth ball (8/9 spherical shell) centered on the isocenter 5a. Exercise like drawing.
The O-type gantry 69, the ring circumferential movement mechanism 70, the O-type drive rings 71-1 and 71-2, and the gantry rotation mechanism 73 are made of a material having high rigidity such as stainless steel, for example. The O-type gantry 69 (main body) has a width of 200 to 400 mm, a thickness of 100 to 200 mm, and a radius of 1200 to 2000 mm from the isocenter 5a.

  The X-ray head 10 is a radiation irradiation head that irradiates the irradiation field 5 ′ (affected area 5) with the therapeutic X-ray 3 a. A small electronic linac that emits therapeutic X-rays 3a is provided. The O-type gantry 69 is movably attached via an O-type drive ring 71, a support frame 67-1 (described later) and a support frame 67-2 (described later). A support frame 102 is provided.

The support frame 102 includes a first swing mechanism 131 and a second swing mechanism 132.
The first swing mechanism 131 is a mechanism that swings (rotates) the X-ray head 10 on the O-type gantry 69 as R1 around the first swing axis S1. The first swing axis S1 is provided on or in the vicinity of an axis that substantially passes through the center of inertia of the X-ray head 10 so that the inertia when the X-ray head 10 swings becomes small.
The second swing mechanism 132 is a mechanism that swings (rotates) the X-ray head 10 on the O-type gantry 69 as R2 around the second swing axis S2. The second swing axis S2 is provided on or near an axis that substantially passes through the center of inertia of the X-ray head 10 so that the inertia when the X-ray head 10 swings becomes small. Details will be described later.
The holding frame 76A for holding the sensor array 78A and the holding frame 76B for holding the sensor array 78B are fixedly held.

The support frame 67-1 is fixedly connected on one side to the O-type drive ring 71-1, and on the other side to the support frame 102. The support frame 67-2 has one side fixed to the O-type drive ring 71-2 and the other side fixed to the side facing the connecting portion between the support frame 102 and the support frame 67-1 in the support frame 102. Connected to.
That is, the support frame 67-1 and the support frame 67-2 hold the X-ray head 10 on the inner peripheral side of the O-type gantry 69. Then, the O-type drive rings 71-1 and 71-2 rotate together with the X-ray head 10 held by the support frame 102 according to the rotation of the ring circumferential movement mechanism 70.

  The real-time imager 74 irradiates diagnostic X-rays 3b, which are weak fan beam X-rays, into the treatment field of the subject 4 from two directions (X-ray sources 77A and 77B), and detects transmission images (sensor array 78A). 78B). Then, the detected data is subjected to image processing (imager signal processing device 31) to display a three-dimensional tomographic diagnosis image of the treatment field 5 on the computer screen. The real-time imager 74 is controlled by the system controller 80. The real-time imager 74 is a set of two sets of X-ray sources 77A and 77B and sensor arrays 78A and 78B that constitute a normal X-ray camera, a holding unit 68 that holds the X-ray sources 77A and 77B, and sensor arrays 78A and 78B. Holding frames 76A and 76B.

  One side of the holding portion 68 (-1 and -2) is fixedly held by the O-type drive rings 71-1 and 71-2. On the other side, X-ray sources 77A and 77B are respectively held on both sides of the plane formed by the first rotation axis J1 and the second rotation axis J2 so as to aim at the isocenter 5a. Furthermore, a protection plate 75 that absorbs the therapeutic X-ray 3a that has passed through the subject 4 is provided at the top. Then, the X-ray sources 77A and 77B are moved in conjunction with the movement of the X-ray head 10 (the movements of the O-type drive rings 71-1 and 71-2).

One side of the holding frame 76A extends downward from one side surface of the X-ray head 10 (support frame 102). The sensor array 78A is connected to the other side.
Similarly, the holding frame 76B extends downward from the other side surface of the X-ray head 10 (support frame 102) on one side. The sensor array 78B is connected to the other side.

The X-ray source 77 </ b> A and the X-ray source 77 </ b> B are provided in the holding unit 68. The first rotation axis J1 and the second rotation axis J2 are opposite to each other across a plane formed by the first rotation axis J1 and the second rotation axis J2. The same applies to the sensor array 78A and the isocenter 78B. Since diagnostic images are obtained by irradiating diagnostic X-rays 3b from two directions, the movement of each part in the body of the patient 4 can be grasped quickly and accurately.
The real-time imager 74, the O-type drive rings 71-1 and 71-2, and the O-type gantry 69 are mechanically closely coupled and have a common coordinate reference.

  The sensor array 78A is provided at one end of the holding frame 76A. Although it is arranged in the vicinity of the X-ray head 10 so as not to interfere with the path of the therapeutic X-ray 3a irradiated from the X-ray head 10, it is not affected by the powerful X-rays of the X-ray head 10. It will end. And the perpendicular from the center part of the sensor side light-receiving surface faces the isocenter 5a, and the X-ray source 77A is arranged on the extended line. Similarly, the sensor array 78B is provided at one end of the holding frame 76B. Although it is arranged in the vicinity of the X-ray head 10 so as not to interfere with the path of the therapeutic X-ray 3a irradiated from the X-ray head 10, it is not affected by the powerful X-rays of the X-ray head 10. It will end. And the perpendicular from the center part of the sensor side light-receiving surface faces the isocenter 5a, and the X-ray source 77B is arranged on the extended line.

  The sensor arrays 78A and 78B receive (receive light) the diagnostic X-ray 3b that has passed through the subject 4. It is fixedly arranged on the circumference of a circle centering on the isocenter 5a surrounding the diagnostic space in which the subject 4 is arranged, has a large number of long and high sensitivity CdTe sensors, and has a resolution of 0.5 mm. . The irradiation time of the diagnostic X-ray 3b is 0.0025 to 0.01 seconds per shot.

  The distance between each of the X-ray sources 77A and 77B and the sensor arrays 78A and 78B and the isocenter 5a is smaller than the distance between the X-ray head 10 and the isocenter 5a. That is, since the X-ray source and the sensor array are close to the patient 5, the image quality of the diagnostic image is improved. In addition, the movable range of the X-ray head 10 on the O-type gantry 69 can be widened.

  It is preferable that an angle formed by a perpendicular passing through the isocenter 5a from the center of the surface of the sensor array 78A and a perpendicular passing through the isocenter 5a from the center of the surface of the sensor array 78B is 20 ° to 90 °. More preferably, the angle is 40 ° to 60 °. This is set based on the condition that the X-ray head 10, the X-ray source 77A, and the X-ray source 77B operate accurately without mutual influence and a diagnostic image having sufficient accuracy can be obtained. Is done.

  On the output side of the X-ray generation control device of the real-time imager 74, an anode, a cathode, and a grid electrode in the power source and the X-ray sources 77A and 77B are respectively connected. When an X-ray generation command signal is output from the system control device 80 to the X-ray generation control device, the X-ray generation control device controls the power feeding operation from the power source to the electron gun drive circuit based on the command. . In response to this, an electron beam is emitted from the cathodes in the X-ray sources 77A and 77B, the negative bias voltage applied to the grit electrode is released to zero potential, and the electron beam passes through the hole in the grit electrode and reaches the anode. Incident. When an electron beam enters the anode, secondary X-rays are generated from the anode, and fan-shaped therapeutic X-rays 3b are emitted toward the patient 4 via a collimator attached to the window.

  The X-ray transmission data detected by the sensor arrays 78A and 78B is converted into a current signal proportional to the transmitted X-ray dose, sent to the image signal digitizer and data recording device via the preamplifier and main amplifier, and as diagnostic image data. It will be recorded. Imaging, data recording, and the like by the diagnostic X-ray 3b are controlled by the system controller 80. The recorded diagnostic image data is output from the data recording device to an imager signal processing device 31 (described later), and data processing is performed by the imager signal processing device 31. The processed data is reproduced and displayed on the display of the system control device 80 as a diagnostic image of the affected part 5.

  The above three-axis drive (I1, I2) allows the X-ray head 10 to move in an isocentric manner on the 8/9 spherical shell centered on the isocenter 5a (the X-ray head 10 faces the isocenter 5a). It becomes. Furthermore, by the above-described two-axis drive (R1, R2), the X-ray head 10 moves in a pseudo non-isocentric manner on the 8/9 spherical shell (the X-ray head 10 is three-dimensional near the periphery of the isocenter 5a. Can be directed to a desired point in the region 5b (see FIG. 1). Since this pseudo non-isocentric motion is a swing motion around the center of inertia of the X-ray head 10, it is possible to perform a quick motion at each stage as compared with the isocentric motion. The quasi-non-isocentric high-response quick tracking motion enables the head aiming to be followed with high response and high precision even for fast movement such as heartbeat.

  The microwave generator 20 includes a klystron (not shown) and generates microwaves by a klystron system. Then, it has a circulator 21 and a dummy load 22 related to the waveguide, and supplies microwaves for electron acceleration to the X-ray head 10 via the driven waveguide system 61. Here, a microwave of C band (5.6 GHz) is supplied. The microwave generator 20 is controlled by the system controller 80.

The driven waveguide system 61 is a waveguide that supplies the microwave generated by the microwave generator 20 to the X-ray head 10. The link arm 62-1, the joint part 64a, the link arm 62-2, the joint part 64b, the link arm 63, the joint part 64c, the link arm 65, the joint part 66, and the X-ray head 10 are connected to each other to form a link mechanism. ing. The joint portion 64a can rotate around an axis in the direction of the first rotation axis J1, and the joint portion 64b, the joint portion 64c, and the joint portion 66 can rotate around an axis in the direction of the second rotation axis J2. The X-ray head 10 at the tip of the link slides along the O-type gantry 69 by the movement of the O-type drive ring 71-1, and is swung around the joint portion 66 by the first swing mechanism 131. .
The joint portions 64a, 64b, 64c, and 66 include a rotary RF coupler 50 (described later) that transmits microwaves by axial rotation. The link arms 62-1, 62-2, 63, and 65 include a waveguide 51 (described later), and are electromagnetically communicated by joint portions 64a to 64c and 66. The microwave generated by the microwave generator 20 is supplied to the X-ray head 10 via the joint part 64a, the link arm 62, the joint part 64b, the link arm 63, the joint part 64c, the link arm 65, and the joint part 66. The

  A SAD (Source Axis Distance) shown in FIG. 1 corresponds to a distance from the isocenter 5a to a target 121 (described later) in the X-ray head 10. In this embodiment, the reference SAD is set to 80 to 100 cm.

  Next, the X-ray head 10 will be described in detail with reference to FIGS. 3 and 4.

FIG. 3 is a diagram showing a configuration of the X-ray head 10 applied to the radiotherapy apparatus of the present invention. 3A is an overall view, FIG. 3B is an AA sectional view of FIG. 3A, and FIG. 3C is a BB sectional view.
The X-ray head 10 includes a small electronic linac that generates a therapeutic X-ray 3a having an electron energy of 4 MeV to 10 MeV. The O-type gantry 69 is movably supported through a support frame 102 and the like. At the same time, it is connected to a joint 66 (rotary RF coupler) of the driven waveguide system 61 so as to be swingable.

  In the X-ray head 10, the main body portion of the X-ray head 10 is covered with a head cover 101, and an emission portion 120 for emitting radiation is attached to the distal end side of the main body portion. In the head cover 101 covering the head main body, an electric circuit / cooling water circuit 116, an acceleration pipe 110, an RF window 52, a waveguide 51, a part 50B of a rotary RF coupler, an exhaust pipe 107, an ion pump 112, and target exhaust A chamber 119, a target 121, and a cooling plate 122 are provided.

A cable (not shown) connected from the insulating glass 103 at the tail of the acceleration tube 110 to an external power source (not shown) is introduced into the head cover 101 and connected to the cathode 105 of the electron gun 104. An anode 106 is disposed so as to face the cathode 105. The power source of the electron gun 104 is controlled by the system controller 80.
An exhaust pipe 107 communicating with the ion pump 112 is exhausted between the cathode 105 and the anode 106. The exhausted space continues from the electron gun 104 to the acceleration tube 110, and further continues from the acceleration tube 110 to the emission unit 120. Since the ion pump 112 is directly connected to the acceleration tube 110, the degree of vacuum of the acceleration tube 110 can always be kept at a high vacuum, and a stable electron beam can be stably accelerated. As a result, the therapeutic X-ray 3a can be stably output.
The length from the insulating glass 103 to the tip of the acceleration tube 110 is about 360 mm. This size is significantly reduced in size and weight to about 1/3 of the conventionally used acceleration tube. This is because a microwave of high frequency (high energy) C band (5.6 GHz) is used instead of a conventionally used S band microwave.

FIG. 4 is an enlarged view of the vicinity of the electron gun 104 and the acceleration tube 110 in FIG.
The central hole of the anode 106 of the electron gun 104 communicates with the buncher cavity 109 of the acceleration tube 110. Inside the acceleration tube 110, a plurality of acceleration cavities 111b having a central hole for passing an electron beam are further connected. The accelerating tube 110 is accelerated by the microwave while passing the electron beam emitted from the electron gun 104 through the central hole 111c of the buncher cavity 109 and the plurality of accelerating cavities 111b, and as an X-ray target 121 as a high energy electron beam. Collide with. The acceleration cavity 111b communicates with the pair of left and right side exhaust pipes 108 via the side couple cavity 111a. The pair of left and right side exhaust pipes 108 are connected to the ion pump 112 via the exhaust pipe 107 and evacuated.

  Referring to FIG. 3, the waveguide 51 communicates with the acceleration tube 110. The waveguide 51 communicates with the microwave generator 20 via a ceramic RF window 52 and rotary RF couplers 50A and 50B (-driven waveguide system 61-). The RF window 52 is an entrance for introducing the microwave into the acceleration tube 110 while preventing leakage of the SF6 gas sealed in the waveguide 51.

  The emission unit 120 is provided at the tip of the main body of the X-ray head 10 covered with the head cover 101. A target 121, a cooling plate 122, a primary collimator 123, and a flattening filter 124 are provided. From the electron gun 104 through the accelerating tube 110 to the flattening filter 124, they are arranged in series along the optical axis of the electron beam. Then, the accelerated electron beam enters the target 121 of the emission unit 120 through the target exhaust chamber 119.

  The target 121 emits bremsstrahlung X-rays when high-energy accelerated electrons are incident. A target cooling plate 122 is attached so as not to be damaged by heat generated when the braking X-rays are emitted. For the target 121, a refractory metal such as tungsten or tantalum or an alloy thereof is used.

  The primary collimator 123 is made of a material having excellent shielding properties against radiation such as tungsten and generating little thermal neutrons. X-rays from the target 121 are guided to the flattening filter 124 with a predetermined beam width.

  The flattening filter 124 averages the intensity of the X-rays emitted from the target 121 to obtain the therapeutic X-ray 3a having a uniform dose distribution.

  Further, a secondary collimator 125 and an ionization chamber 126 for dose measurement are attached to the distal end side of the emission unit 120. The secondary collimator 125 is made of a highly shielding material such as tungsten that cannot transmit the therapeutic X-ray 3a. The therapeutic X-ray 3 a obtained by narrowing the X-rays from the flattening filter 124 to a predetermined beam width is guided to the ionization chamber 126. This secondary collimator 125 is detachably screwed into the end surface portion of the primary collimator 123.

  The ionization chamber 126 measures the dose of X-rays that pass through. It is attached to the tip of the secondary collimator 125 and encloses a gas of a predetermined component. A detection circuit (not shown) for detecting the discharge charge is connected. This detection circuit is connected to the input side of the system controller 80. The system controller 80 calculates the X-ray dose emitted from the X-ray head 10 based on the input signal of the dose measurement ionization chamber 126 and stores it in the memory as treatment dose data received by the patient 4. ing.

In the radiotherapy apparatus 6 of the present invention, the X-ray head 10 has a total length of 500 to 600 mm, a width of 500 mm, a depth of 300 mm, a weight of 60 to 80 kg, and a high energy of 4 MeV to 10 MeV. It is possible to generate therapeutic X-rays 3a having electronic energy. This is because the high-frequency (high energy) C-band (5.6 GHz) microwave is used, so that the acceleration tube 110 is small and light, and since the acceleration tube 110 is small, the deflecting magnet that deflects the electron beam and its This is because related equipment is unnecessary, and a device for generating microwaves (microwave generator 20) is arranged outside the X-ray head 10. That is, since the overall weight is reduced and the overall size is reduced, the X-ray head 10 can be quickly and quickly moved to a desired place with less force. It becomes.
Further, if an acceleration tube that can be accelerated using microwaves of a higher frequency X band is used, the size and weight can be further reduced. In that case, by changing the design of each device in accordance with the frequency of the microwave (example: changing the size of each component of the driven waveguide system 61, the size of the acceleration cavity 111b of the acceleration tube 110, etc.), It can be implemented.

  Next, the biaxial swing mechanism of the X-ray head 10 will be described in detail with reference to FIGS.

FIG. 5 is a perspective view showing the X-ray head 10 supported by the support frame 102.
As shown in FIG. 5, the head head cover 101 of the X-ray head 10 is supported by a support frame 102 having a gimbal structure. The support frame 102 is attached to a position coordinate through which the first swing axis S1 and the second swing axis S2 including the inertia center of the X-ray head 10 pass. Then, the first swing mechanism 131 swings around the first swing shaft S1 like R1. Similarly, the second swing mechanism 132 swings around the second swing axis S2 like R2.

FIG. 6 is a diagram illustrating the configuration of the biaxial swing mechanism of the support frame. 6A is an entire view, FIG. 6B is an S1 swing drive servomotor 131b, FIG. 6C is a joint 66, and FIG. 6D is an S2 swing drive servomotor 132b. FIG. 6E shows a pair of rotary RF couplers 50A and 50B.
As shown in FIG. 6 (a), the support frame 102 includes a joint 66 (rotary RF coupler) of the driven waveguide system 61 and an S1 swing drive servomotor 131b having a first swing axis S1. Are attached to two opposite sides. Similarly, a pair of rotary RF couplers 50A and 50B and an S2 swing drive servomotor 132b are respectively attached to two opposing sides different from the aforementioned two sides along the second swing axis S2. .

  As shown in FIGS. 6A, 6B, and 6C, the joint 66 (rotary RF coupler) of the driven waveguide system 61 is attached to the center of the long side on one side of the support frame 102. The drive shaft 131a of the S1 swing drive servomotor 131b is attached to the center of the opposed long side of the frame 102 so as to face the first swing shaft S1. The S1 swing drive servomotor 131b is fixedly supported by the support frame 67-2. When the servo motor drive shaft 131a is rotationally driven, the X-ray head 10 swings around the first swing shaft S1 like R1.

  As shown in FIGS. 6A, 6D, and 6E, the pair of rotary RF couplers 50A and 50B are attached to the center of the short side on one side of the support frame 102, and face the S2 neck so as to face this. The drive shaft 132a of the swing drive servomotor 132b is attached to the center of the opposing short side of the support frame 102 so as to overlap the second swing shaft S2. The main body of the S2 swing drive servomotor 132b is fixedly supported by the bracket 102a on the support frame side, and the drive shaft 132a is rotatably supported by the support frame 102 via a bearing 133. When the servo motor drive shaft 132a is driven to rotate, the X-ray head 10 swings around the S2 drive shaft.

  As shown in FIG. 6A, a waveguide 51 is provided in each link arm 63, 65 of the driven waveguide system 11, and a rotary RF coupler 50 is provided in each joint portion 64, 66. Further, microwaves are introduced into the accelerating tube 110 in the X-ray head 10 through a pair of rotary RF couplers 50A and 50B.

  Next, a rotary RF coupler that is a joint portion of a waveguide that transmits microwaves will be described with reference to FIGS.

FIG. 7 is a diagram showing a configuration of a joint portion having a rotary RF coupler 50 inside. In FIG. 7, the joint portion 64c is shown as a representative, but the same applies to the joint portion 64a, the joint portion 64b, the joint portion 66, and the pair of rotary RF couplers 50A and 50B.
As shown in FIG. 7, the waveguide 51 is provided in the link arms 63 and 65, and the waveguide 51 communicates electromagnetically by the rotary RF coupler 50 in the joint portions 64 a to 64 c and 66. ing.

FIG. 8 is a perspective view showing details of the configuration of the rotary RF coupler 50 shown in FIG.
As shown in FIG. 8, the rotary RF coupler 50 is connected to each of the waveguides 51 by flange joints 53 and 54. The rotary RF coupler 50 transmits the microwave for accelerating the waveguide 55a to the waveguide 55b by axial rotation.

FIG. 9A is a cross-sectional view showing details of the rotary RF coupler 50 of FIG. FIG. 9B shows an example of a microwave mode in the rotary RF coupler 50.
As shown in FIG. 9A, the waveguides 55 a and 55 b of the waveguide 51 communicate with the rotation space surrounded by the rotation members 56 and 57 of the rotary RF coupler 50, the bearing 58, and the λ / 4 wavelength choke 59. Then, the microwave is guided in the in-tube mode (electric field lines 2a (2b)) as illustrated in FIG. 9B. By the combination of the rotary RF coupler 50 and the waveguide 51, the microwave for acceleration is smoothly supplied from the microwave generator 20 such as a klystron fixed on the ground to the moving X-ray head 10. I can do it.

  Next, the control system of the embodiment of the radiotherapy apparatus of the present invention will be described.

FIG. 10 is a block diagram showing a control system of the embodiment of the radiotherapy apparatus of the present invention.
The control system of this embodiment includes a treatment bed system 7, an X-ray head system 8, a real-time imager 74, an imager signal processing device 31, a microwave generation device 20, a system control device 80, and a system utility 90. In essence, the system controller 80 controls the entire system.

  The system controller 80 includes a system control computer, and includes a system management algorithm as a computer program, an image tracking algorithm, a treatment plan algorithm, a treatment management algorithm, a graphical user interface (GUI), an interlock algorithm, a treatment plan database, a trend Equipped with a record database and treatment database. In addition, a system monitor (display), an input / output device, and a BIT are included, and other system blocks are connected to each other to exchange input / output signals.

The treatment plan database stores treatment plan information as information on a treatment plan established by a doctor. The treatment plan information is based on various examinations performed before surgery. The treatment plan information associates patient attribute information, patient image information, absorbed dose information, treatment dose information, affected area position information, and the like.
However, the patient attribute information indicates the name, date of birth, etc. of the patient 4. The patient image information indicates an X-ray tomographic image of the patient 4. The absorbed dose information relates to the absorbed dose setting indicating the absorbed dose of radiation (X-rays) to the affected part 5, the irradiation method (number of times, one absorbed dose, irradiation direction (route)) and the like. The therapeutic dose information relates to a therapeutic dose setting indicating a therapeutic dose of radiation (X-rays) to the affected part 5, an irradiation method (number of times, a single therapeutic dose, an irradiation direction (route)), and the like. The affected part position information relates to the position of the affected part 5. The position of the affected part 5 may be a definition area 5-1 described later.

  The trend record database stores irradiation result information related to the results of irradiation treatment. The irradiation result information relates to radiation (X-rays) actually irradiated at the time of treatment. The irradiation result information includes patient attribute information, integrated therapeutic dose, integrated absorbed dose, therapeutic dose for each irradiation direction (number of portals), estimated absorption amount, target coordinates (coordinates of irradiation targets in the affected area 5), and machine coordinates (actual irradiation) The coordinates of the irradiation field 5 ′, etc., which have been

  The treatment database stores a radiation absorption amount curve indicating the relationship between the type of material, the thickness of the material, and the amount of radiation (X-ray) absorbed, and the like.

  The system management algorithm controls the entire system control device 80 such as each algorithm, GUI, system monitor (display), input / output device, and BIT.

  The treatment plan algorithm is based on the treatment plan database (X-ray tomographic image of patient 4 and absorbed dose information) and the treatment database (radiation absorption curve for each substance). Line treatment dose, cumulative treatment dose), etc. And it displays on a display and receives a doctor's confirmation. The doctor changes the irradiation direction, the absorbed dose of X-rays, and the like as necessary to obtain desired treatment dose information. After confirmation by the doctor, it is stored in the treatment plan database.

The treatment management algorithm sets the X-ray head system 8 so that the X-ray head 10 is directed in a predetermined direction based on the treatment plan information in the treatment plan database and / or the swing amount of the X-ray head 10 from the image tracking algorithm. Control.
In addition, irradiation result information obtained from the imager signal processing device 31, the X-ray head system 8, the image tracking algorithm, and the like during treatment is stored in a trend recording database.

  The image tracking algorithm calculates the coordinates of the affected area 5 based on the tracking image data obtained from the imager signal processing device 31. Further, the coordinates of the irradiation field 5 ′ of the X-ray head 10 are obtained based on various data obtained from the X-ray head system 8. Then, based on the coordinates of the affected part 5 and the coordinates of the irradiation field 5 ′, the swing amount of the X-ray head 10 is calculated.

  The interlock algorithm urgently stops the therapeutic X-ray 3a and the diagnostic X-ray 3b when a predetermined condition is satisfied. The predetermined condition is that when the emergency stop button is pressed, when the irradiation field 5 ′ and the affected part 5 are separated by a predetermined distance or more, at least one of the therapeutic dose and the absorbed dose for the patient 4 is If the predetermined allowable value is exceeded, the diagnostic X-ray 3b is stopped when the therapeutic X-ray 3a is irradiated, or the therapeutic X-ray 3a is stopped when the diagnostic X-ray 3b is irradiated. If, etc.

  The X-ray transmission data detected by the real-time imager 74 is reconstructed into a diagnostic image by an image reconstruction algorithm in the imager signal processing device 31 and transmitted to the system control device 80. Thereby, an image diagnosis is generated in real time during the treatment, and the doctor can perform the treatment while viewing the diagnostic image displayed on the computer display of the system control device 80.

  The microwave generator 20 includes a klystron modulator and linac system controller, a klystron, and an RF driver. The klystron is connected to the X-ray head 10 via a driven waveguide system 61 and is a supply source that supplies microwaves to the acceleration tube 110.

  The X-ray head system 8 includes an X-ray head 10, an isocentric drive mechanism (including an O-type gantry 69, a ring circumferential movement mechanism 70, and a gantry rotation mechanism 72), and a swing drive mechanism (first swing mechanism 131). , Including the second swing mechanism 132 and the rotary RF coupler 50). The isocentric drive mechanism and the swing drive mechanism are connected to the system control unit 80 via their corresponding drivers (isocentric drive driver and swing drive driver), and X-rays during isocentric irradiation The isocentric drive mechanism of the head 10 and the biaxial swing drive mechanism of the X-ray head 10 during pseudo-isocentric irradiation are controlled.

  Next, operation | movement of 1st Embodiment of the radiotherapy apparatus which is this invention is demonstrated with reference to an accompanying drawing.

  First, position calibration is performed. In the position calibration, the CCD camera 60 is installed so that the center of the light receiving surface overlaps with the isocenter 5a and the light receiving surface is horizontal, and the laser transmitter is installed in the X-ray head 10 imitating an electronic linac. To do. The deviation between the laser receiving point and the isocenter 5a is used as a correction value.

With the above-described position calibration method, a large machine workpiece such as the O-type gantry 69 can be accurately corrected in a short time with respect to distortion due to work, deflection due to its own weight, etc., stress due to stress during installation, etc. Position accuracy can be improved. In the case of the present embodiment, the position resolution can be set to about 20 μm.
Such position calibration is performed at the time of installation of the radiotherapy apparatus 6 and at a periodic inspection. However, it may be performed every predetermined number of uses and every radiotherapy.

Next, the timing of each operation time in the operation of the embodiment of the radiotherapy apparatus of the present invention will be described.
FIG. 11 is a timing chart in the operation of the embodiment of the radiotherapy apparatus of the present invention. FIG. 11A shows the timing of the operation for processing the diagnostic image, FIG. 11B shows the timing of the image tracking calculation based on the processed diagnostic image and the swing operation of the X-ray head 10, and FIG. c) shows the timing of irradiation of therapeutic X-rays.

(0) Before time t0 First, when the main switch of the radiotherapy apparatus 6 is turned on, the treatment bed system 7, the X-ray head system 8, the real-time imager 74, the microwave generator 20, the system controller 80, and the system utility Each of the 90 power supplies is in a standby state. The treatment bed system 7 is activated, the patient 4 moves into the treatment area together with the treatment bed 7-2, and the real-time imager 74 is activated to treat the affected area 5 so as to coincide with the isocenter 5a of the treatment apparatus. Move the bed 7-2 for alignment. After this isocentric alignment is completed, real-time image diagnosis by the real-time imager 74 and radiation therapy by the X-ray head 10 are started.

(1) Step S2-1: Time t0 to t1
The normal X-ray camera (real-time imager 74) irradiates the irradiation field 5 'with the diagnostic X-ray 3b from the diagnostic X-ray generation unit. Then, the sensor array detects the X-ray transmission data as diagnostic image data. In order to minimize the exposure, the irradiation time of the diagnostic X-ray 3b is limited to t0 to t1.

(2) Step S2-2: Time t1 to t2
The detected diagnostic image data is converted into a current signal proportional to the transmitted X-ray dose, and is taken into the image signal digitizer and the data recording device via the preamplifier and the main amplifier.

(3) Step S2-3: Time t2 to t3
The recorded diagnostic image data is output from the data recording device to the imager signal processing device 31. Then, arithmetic processing is performed using the image reconstruction algorithm of the imager signal processing device 31 and converted into tracking image data. The image data for tracking is data indicating a diagnostic image at each coordinate point (Xi, Yi, Zi), (i = 1 to n: n is the number of data) of the coordinate system of the radiation therapy apparatus 6A. The tracking image data is output to the system control device 80.
The image data for tracking is reproduced and displayed on the display of the system control device 80 as a diagnostic image of the affected part 5.

  The real-time imager 74 and the imager signal processing device 31 repeat the process at the time t0 to t3 again after a predetermined time has elapsed after the time t3. In FIG. 11, the process at time t0 to t3 = the process at time t10 to t13, time t20 to t23.

  In order to prevent direct rays, leakage rays, and scattered rays of the therapeutic X-ray 3a from affecting the sensor array (detector) of the real-time imager 74, at least a time t0 when the diagnostic X-ray 3b is irradiated. In -t1, the X-ray head 10 is interlocked so that the therapeutic X-ray 3a is not irradiated.

  The total time t0 to t3 required for these diagnostic image processes (steps S2-1 to S2-3) is 0.01 seconds. That is, one cycle time of the diagnostic image processing is 0.01 second. This is a sufficient sample rate to follow a fast movement such as a heartbeat.

(4) Step S2-4: Time t3 to t4
The following image tracking calculation is performed using the image tracking algorithm of the system controller 80.
Based on the tracking image data, the coordinates of the affected part 5 (coordinate points (X, Y, Z) in the coordinate system of the radiation therapy apparatus 6) are extracted. On the other hand, based on the position (coordinates), rotation angle, etc. of the ring orbiting movement mechanism 70, gantry rotation mechanism 73, first swing mechanism 131 and second swing mechanism 132, the irradiation field 5 ′ of the current X-ray head 10 is used. (Coordinate points (x, y, z) in the coordinate system of the radiation therapy apparatus 6) are calculated. (1) When the distance L = | (X, Y, Z) − (x, y, z) | between the two points is equal to or smaller than a preset value L02, no swing is performed. 2) When the distance L is greater than or equal to a preset value L01, the swing amount is set to θ0 (corresponding to the distance L01 in the coordinate direction of the affected part 5), and (3) If L02 <distance L <L01, Based on the coordinates and the coordinates of the irradiation field 5 ′, the swing amounts (θ1, θ2) of the X-ray head 10 are calculated.

However, the amount of swing (θ1, θ2) of the X-ray head 10 is a minute displacement angle (swing angle) θ1 (rotation direction, magnitude of rotation angle) around the S1 swing drive axis and around the S2 swing drive axis. Is a minute displacement angle (swing angle) θ2 (rotation direction, magnitude of rotation angle).
L01 is the maximum distance that the X-ray head 10 can swing between times t4 and t5. L02 is a value of an error expected when calculating the coordinate point (X, Y, Z) of the affected part 5 and the coordinate point (x, y, z) of the irradiation field 5 ′.

  The state of movement (movement) of the affected part 5 (coordinate points (X, Y, Z)) is displayed on the display of the system control device 80. However, not only the affected part 5 but also the surrounding area (example: contour line 5-2 including the affected part 5 (described later)) may be indicated in the same manner.

(5) Step S2-5: Time t4 to t5
Based on the calculated swing amounts (θ1, θ2) of the X-ray head 10, a swing drive signal indicating the swing amounts (θ1, θ2) of the X-ray head 10 is generated by the treatment management algorithm of the system controller 80. Are output to the X-ray head system 8.
Based on the swing drive signal, the X-ray head swing drive driver of the X-ray head system 8 drives the first swing mechanism 131 and the second swing mechanism 132 so that the X-ray head 10 faces in a desired direction. .
The system controller 80 repeats the process from time t3 to time t5 again from time t13 after time t5. In FIG. 11, the process at time t3 to t5 = time t13 to t15, time t23 to t25...

  The total time t3 to t5 required for the image tracking calculation and the X-ray head swing (steps S2-4 to S2-5) is 0.01 seconds. That is, one cycle time of image tracking calculation and X-ray head swing is 0.01 second. This is a sufficient rate for following a fast movement such as a heartbeat.

  During the time t4 to t5 during which the S1 swing drive servomotor 131b of the first swing mechanism 131 and the S2 swing drive servomotor 132b of the second swing mechanism 132 are driven, the swing angle malfunctions. Therefore, the X-ray head 10 is interlocked to ensure safety so that the therapeutic X-ray 3a is not irradiated.

(6) Step S2-6: Time t5 to t6
Using the system management algorithm of the system controller 80, a therapeutic X-ray irradiation signal as a signal for instructing irradiation of the therapeutic X-ray 3a is output to the X-ray head 10 at time t5. The interlock of the X-ray head 10 is released, and irradiation of the therapeutic X-ray 3a to the affected part 5 is started. The irradiation time t5 to t6 of the therapeutic X-ray 3a is about 0.0025 to 0.01 seconds. The duty of irradiation is about 50%.
The system controller 80 repeats the process from time t5 to time t6 again from time t15 after time t6. In FIG. 11, the process from time t5 to t6 = time t15 to t16, time t25 to t26...

  The total time t5 to t6 required for this therapeutic X-ray irradiation (step S2-6) is 0.01 seconds. That is, one cycle time of therapeutic X-ray irradiation is 0.01 seconds. This is a sufficient rate for following a fast movement such as a heartbeat.

Here, how the therapeutic X-ray 3a is irradiated while swinging the X-ray head 10 will be further described with reference to the drawings.
FIG. 12 is a perspective view showing a state of radiation therapy using the X-ray head 10. The X-ray head 10 irradiates the affected part 5 with X-rays.
FIG. 13 and FIG. 14 are diagrams for explaining how the therapeutic X-ray 3 a is irradiated while swinging the X-ray head 10. 13 is an AA cross section in FIG. 12, and FIG. 14 is a BB cross section in FIG.
In order to irradiate following the movement of the irradiation field 5 ′, the system control device 80 calculates the position (coordinates (X, Y, Z)) of the affected part 5 and the current X at the time t3 to t4. Based on the coordinates (x, y, z) of the irradiation field 5 ′ of the line head 10, shift amounts DV1 and DV2 from the irradiation field 5 ′ of the affected part 5 in the X-axis direction and the Y-axis direction are calculated. Then, based on the shift amounts DV1 and DV2, the displacement angles θ1 and θ2 due to the movements around the first swing drive shaft S1 and the second swing drive shaft S2 are obtained using a predetermined calculation formula, respectively.
At the time t5 to t6, the X-ray head 10 is swung by the displacement angle θ1 around the first swing drive axis S1 and by the displacement angle θ2 around the second swing drive axis S2. Then, simultaneously with stopping the swing, the therapeutic X-ray 3a is emitted from the X-ray head 10.

  By the above steps S2-1 to S2-6, the affected part 5 such as a tumor moving under the influence of the movement and state of the organ, such as breathing and heartbeat below the cervix, peristalsis and urine volume in the bladder, The aim of the X-ray head 10 follows quickly and with high response, and radiation (X-rays) can be irradiated with high accuracy. That is, the X-ray head 10 can be swung within 0.03 seconds including the diagnostic image processing time to irradiate radiation (X-rays), and the movement of the irradiation field (affected area) can be quickly performed. It can be followed.

In the above-described process, at step S2-4: at times t3 to t4, the angle at which the X-ray head 10 is swung in step S2-5 is limited to a predetermined size. This is because as the swing angle increases, the time required for swinging becomes longer, and the affected part 5 further moves during that time. As a result, the coordinate point (x, y, z) of the irradiation field 5 ′ of the X-ray head 10 is greatly deviated from the position of the coordinate point (X, Y, Z) of the affected part 5.
The fast movement of the affected part 5 tracked by the X-ray head 10 is due to breathing and heartbeat. In this case, the affected part 5 is moving in substantially the same region (however, the route is not necessarily the same). Therefore, once the coordinate point (x, y, z) of the irradiation field 5 ′ of the X-ray head 10 and the coordinate point (X, Y, Z) of the affected area 5 may not completely match, they will match thereafter. It is possible to make it.

If an abnormality occurs in the acquisition of diagnostic image data or image tracking calculation, the irradiation of the therapeutic X-ray 3a is interlocked at that time to stop the irradiation, thereby ensuring safety. This apparatus is designed to irradiate the therapeutic X-ray 3a after confirming that the X-ray head 10 has been swung and positioned normally.
If the difference between the coordinate point (x, y, z) of the irradiation field 5 ′ and the coordinate point (X, Y, Z) of the affected part 5 is greater than or equal to a preset value, step S2- The irradiation of the therapeutic X-ray 3a at 6 (time t5 to t6) is not performed.

In addition, the system control device 80 may move the ring orbiting movement mechanism 70, the gantry rotation mechanism 72, and the treatment bed system 7 as necessary so that the X-ray head 10 is aimed at the affected area 5. Is possible.
That is, the system control device 80 performs the swing amount (the first swing mechanism 131 and the second swing motion of the X-ray head 10 based on the coordinates of the affected part 5 and the coordinates of the irradiation field 5 ′ at time t3 to t4. And a moving amount (for the ring orbiting moving mechanism 70, the gantry rotating mechanism 73, and the treatment bed system 7) are calculated. Next, the amount of swing and the amount of movement of the X-ray head 10 are output to the X-ray head system 8 from time t4 to t5. Then, the first swing mechanism 131, the second swing mechanism 132, the ring orbiting movement mechanism 70, the gantry rotation mechanism 73, and the treatment bed system 7 are moved, and the X-ray head 10 is aimed at the affected area 5.

  After the irradiation of the therapeutic X-ray 3a is stopped, the irradiation of the diagnostic beam 3b is started at the timing t5, and the process proceeds to the next diagnostic image processing cycles t5 to t8. Next, the interlock of the X-ray head 10 is released at timing t3 after the diagnostic image processing, and the irradiation of the treatment beam 3a is resumed.

  Thus, diagnostic image processing cycle (0 to Ta in FIG. 11): 0.01 second, image tracking calculation cycle and X-ray head swing cycle (Ta to Tb in FIG. 11): 0.01 second, And a treatment X-ray irradiation cycle (Tb-Tc in FIG. 11): A cycle of 0.01 seconds in total of 0.03 seconds is repeated. That is, the radiation irradiation head can be accurately directed to the irradiation target in a cycle shorter than 1/30 second (= 0.033 second), and the affected part (treatment field) has the fastest movement such as heartbeat. However, the irradiation target can be accurately tracked in real time and the radiation can be irradiated.

Next, a pseudo non-isocentric treatment procedure will be described.
FIG. 15 is a flowchart showing a pseudo non-isocentric treatment procedure on the display.

(1) Step S3-1
In radiation therapy, a doctor makes a treatment plan. The treatment plan is based on various tests performed before surgery. Those treatment plans are stored in a treatment plan database.
Furthermore, a doctor can perform highly accurate and highly reliable radiotherapy by performing real-time image diagnosis of a lesion in an affected area by using the radiotherapy apparatus of the present invention during surgery.

(2) Step S3-2
As shown in FIG. 15A, the diagnostic image of the affected area 5 and the vicinity thereof is reconstructed using the real-time imager 74 and the imager signal processing device 31, and is reproduced and displayed on the display of the system control device 80.
The reconstruction of the diagnostic image is performed by the above steps S2-1 to S2-3. However, step S2-4 to step S2-6 are not performed at this stage.

(3) Step S3-3
As shown in FIG. 15B, the doctor confirms each sectional view of the affected part 5 on the display and defines the outline of the irradiation field 5 ′ for image tracking. Here, prior to the start of treatment, the mapping of the irradiation field 5 ′ has been completed (treatment plan database), and the contour of the irradiation field 5 ′ is defined by a plurality of slices with reference to this. The region defined by the contour is the definition region 5-1, and the definition region 5-1 includes the affected part 5. The definition area 5-1 is stored in the treatment plan database.
The treatment plan algorithm calculates treatment dose information (X-ray treatment dose for each irradiation direction (route), integrated treatment dose) and the like based on the treatment plan database (including the definition area 5-1) and the treatment database. To do. And it displays on a display and receives a doctor's confirmation. The doctor changes the irradiation direction, the absorbed dose of X-rays, and the like as necessary to obtain desired treatment dose information. After the doctor confirms, the treatment dose information is stored in the treatment plan database.

(4) Step S3-4
As shown in FIG. 15C, image contour extraction is performed by the image tracking algorithm of the system control device 80. That is, pattern matching between the actual diagnostic image of the affected area 5 and the defined outline of the definition area 5-1 is performed and displayed as the outline 5-2 (described later). Then, image tracking is started. The doctor visually confirms the image tracking status.
Image tracking is performed in step S2-4. Therefore, step S2-1 to step S2-4 are repeated. However, step S2-5 to step S2-6 are not performed at this stage.

(5) Step S3-5
As shown in FIG. 15D, after the image tracking is stabilized, the doctor operates the master arm switch (Master Arm SW) to set the X-ray head system 8 to the ARMED state. The X-ray head system 8 displays the irradiation volume in red on the display with the crosshair line as the aim. Simultaneously with image tracking, tracking (swinging) of the X-ray head 10 is also performed. Since tracking by the image and the X-ray head 10 continues, the aim and the irradiation volume automatically follow as the irradiation field 5 ′ moves.
Tracking (swinging) of the X-ray head 10 is performed by the above step S2-5. Therefore, step S2-1 to step S2-5 are repeated. However, since the therapeutic X-ray 3a is not released at this stage, step S2-6 is not performed.

(6) Step S3-6
As shown in FIG. 15 (e), irradiation of the therapeutic X-ray 3a is started by a doctor's trigger operation. The planned irradiation time is determined at the stage of treatment planning, and a countdown is started on the display. On the other hand, the irradiation time of one irradiation (step S2-6: time t5 to t6) is also determined. Therefore, the count decreases while repeating the irradiation for a short time (time t5 to t6). And when it finally becomes zero, the therapeutic X-ray 3a automatically stops. The therapeutic dose of the therapeutic X-ray 3a is detected by the ionization chamber 126 and output to the therapeutic management algorithm.
The irradiation with the therapeutic X-ray 3a is performed by the above step S2-6. Therefore, step S2-1 to step S2-6 are repeated.
Moreover, the irradiation management information (all or a part) obtained from the imager signal processing device 31, the X-ray head system 8, the image tracking algorithm, etc. during the treatment is continuously displayed on the display by the treatment management algorithm. . The doctor continues the irradiation by continuing the trigger while confirming the irradiation result information (all or a part thereof). Irradiation result information is stored in a trend recording database.
The system control device 80 continues sampling of the diagnostic image (tracking) and irradiation of the therapeutic X-ray 3a alternately at high speed, and continues image tracking and irradiation of the therapeutic X-ray in real time. Even before the countdown reaches zero, if the doctor releases the trigger, the therapeutic X-ray 3a immediately stops at that timing, so safety is sufficiently ensured.

(7) Step S3-7
As shown in FIG. 15F, the doctor sets the master arm switch to the SAFE position, puts the system in a safe state, and moves the X-ray head 10 to the next irradiation position.
At this stage, the above steps S2-1 to S2-3 are performed. And step S2-4-step S2-6 are not performed.
The doctor confirms the total dose corresponding to the total accumulated dose at the end of irradiation at each portal and at the end of a series of irradiations. That is, the treatment management algorithm reads data from the trend record database and displays the cumulative dose and the cumulative dose distribution within one course on the screen. Data relating to treatment is stored in a treatment file (including irradiation result information) created for each patient 4 in the trend record database.

Here, the method of pattern matching between the actual diagnostic image of the affected area 5 and the outline of the definition area 5-1 in step S3-4 will be further described.
FIG. 16 is a diagram showing the relationship between the affected part 5, the definition area 5-1, and the contour line 5-2 by pattern matching. 16A shows the relationship between the affected area 5 and the definition area 5-1, and FIGS. 16B to 16E show the relationship between the affected area 5 and the contour line 5-2.

(1) Step S4-1
As shown in FIG. 16A, the doctor shows the definition area 5-1 on the display in the manner of a drawing tool with a touch pen that can draw on the display or a pointer such as a mouse.
(2) Step S4-2
The treatment planning algorithm extracts a diagnostic image in the definition area 5-1 based on the definition area 5-1 drawn on the display and the diagnostic image on the display. Then, the shape, coordinates, and brightness distribution of the diagnostic image are grasped. Alternatively, the shape, coordinates, and lightness distribution of the diagnostic image are grasped by extracting the shape of the lightness range that occupies a predetermined ratio (example 90%) of the definition area 5-1 as shown in FIG. .
(3) Step S4-3
The treatment planning algorithm obtains the center of gravity of the shape in the range of the definition area 5-1 or the shape of the lightness range indicating a predetermined ratio. Then, “+” is displayed on the display. For example, the center of gravity of the definition area 5-1 (FIG. 16A) is as shown in FIG. The center of gravity of the lightness range (FIG. 16 (b)) showing a predetermined ratio is as shown in FIG. 16 (d). As shown in FIG. 16E, only the center of the definition area 5-1 may be shown.
Thus, the pattern matching is finished.

  On the display, a binarized display may be performed in which the range of the definition area 5-1 or the brightness range indicating the brightness range indicating a predetermined ratio is displayed in a specific color, and the others are displayed in other colors. Is possible. The definition area 5-1 and the like can be easily distinguished.

However, the lightness distribution is grasped as follows.
FIG. 17 is a graph showing an example of brightness distribution in a diagnostic image. The vertical axis is the brightness, and the horizontal axis is the position of the diagnostic image.
It can be seen from the graph that the brightness in the diagnostic image definition area 5-1 is in the range of L1 to L2. Therefore, the brightness range of the definition area 5-1 is L1 to L2.
Further, the lightness range occupying a predetermined ratio (example 90%) of the definition area 5-1 occupies an area of a predetermined ratio (example 90%) of the definition area 5-1 in the lightness ranges L1 to L2. Is a continuous lightness range L3 to L4. In this case, L2 = L4.
In addition, since the other position which shows the same brightness is away from the definition area 5-1, it is not recognized.

  According to the treatment apparatus of the present embodiment, the radiation irradiation head (X-ray head 10) is swung at a high speed within 0.02 seconds including image processing to follow the movement of the irradiation field (affected area). Therefore, radiation can be irradiated with high accuracy (irradiation time 0.01 seconds). In this way, it is possible to perform non-isocentric irradiation with high response and high accuracy in response to the movement of the affected area, so organ movement such as breathing and heartbeat, peristalsis and urine volume in the bladder, etc. It becomes possible to treat a site where an irradiation target such as a tumor moves under the influence of the condition or the state of treatment.

  Since soft tissue with low contrast cannot be imaged, the irradiation field can be positioned in advance by X-ray CT, MRI, or the like based on landmarks with high contrast such as bone tissue. Alternatively, a small gold plate or the like is embedded in the vicinity of the irradiation field to be used as a marker, or a device such as DSA (Digital Subtraction Angiography) can be used to enhance the image by contrast agent or differential image processing. In X-ray CT and PET, high-speed real-time image reconstruction calculation is performed for real-time imaging.

  In the radiotherapy apparatus of the present invention, the state of the treatment field is monitored in real time by a real-time imager (X-ray system) operating in conjunction with the X-ray head (radiation irradiation head) even during radiation irradiation treatment. Is possible.

  Further, in the radiotherapy apparatus of the present invention, the sensor array (image detector) of the real-time imager (X-ray system) is on the X-ray head (radiation irradiation head) side and interlocks with its movement. Therefore, it is possible to eliminate the influence of therapeutic radiation (X-rays) on the sensor array.

In addition, since the set of the X-ray source-sensor array has a fixed positional relationship with respect to the X-ray head 10, it is difficult to control the calculation for obtaining the diagnostic image and the operation of the real-time imager. This burden can be greatly reduced.
Further, since the sensor array is attached to the X-ray head side, the therapeutic X-ray 3a, which is a very powerful X-ray, does not enter the sensor array.

  Furthermore, the radiotherapy apparatus of the present invention uses an O-type gantry. Therefore, the X-ray head (radiation irradiation head) can move within a very wide range of the 8/9 spherical shell, and irradiation can be performed from a desired angle with respect to the treatment field. The O-type gantry is structurally stable and has high strength. Therefore, there are very few problems such as distortion and inertia of the apparatus, and alignment of the X-ray head and aiming of radiation irradiation can be performed accurately.

  In addition, even when the treatment field in radiotherapy moves, the gimbal mechanism enables quick aiming from a wide range of areas, and irradiation can be performed while quickly following the treatment field.

  And since the radiation therapy apparatus of this invention can perform irradiation of a radiation correctly, it can reduce the irradiation amount of a radiation, improving a therapeutic effect. That is, the burden on the patient can be reduced.

(Example 2)
A second embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.
18-19 is a front view which shows the structure in 1st Embodiment of the radiotherapy apparatus which is this invention. Some parts are omitted from the figure. A coordinate 200 indicates a three-dimensional orthogonal coordinate having the X axis, the Y axis, and the Z axis in FIGS.
The radiotherapy apparatus 6B includes a treatment bed system 7, an X-ray head 10, a support frame 67-1, a support frame 67-2, a C-type gantry 89, a driven waveguide system 61, a microwave generator 20, and a real-time imager. 30.

The C-type gantry 89 includes a head circumferential movement mechanism 33, a gantry rotation mechanism 72, and an upper support mechanism 82.
The C-type gantry 89 (main body) is provided to surround the treatment bed 7-2 and has a C-shape in which a tube having a rectangular cross section is removed from a part of the ring. It is installed on the gantry rotating mechanism 72 so as to stand upright with respect to the horizontal plane (XY plane). Then, the treatment bed 7-2 and the X-ray head 10 are arranged so that the center of a circle (a circle before being C-shaped except for a part thereof, hereinafter also referred to as “virtual circle”) is the isocenter 5a. .

The gantry rotating mechanism 72 and the upper support mechanism 82 are the same as those in the first embodiment except that the C-type gantry 89 is targeted.
As shown in H3 of FIG. 18, the head circling mechanism 33 moves the X-ray head 10 around the C-type gantry 89 (main body) along the C-type gantry 89 (main body). A rack and pinion method or a belt method can be adopted.
The wiring 32 is a wiring for control, power supply, etc. used for the X-ray head 10, the real-time imager 30, and the head circumferential movement mechanism 33.

The C-type gantry 89 can rotate 340 ° around the first rotation axis J1. Further, the head circumferential movement mechanism 33 allows the X-ray head 10 and others (described later) to rotate 240 ° along the C-type gantry 89 about the isocenter 5a. That is, the X-ray head 10 and others (described later) move so as to draw about two-thirds of the sphere (2/3 spherical shell).
The C-type gantry 89, the head circumferential movement mechanism 33, the gantry rotation mechanism 72, and the upper support mechanism 82 are made of a material having high rigidity such as stainless steel, for example. The C-type gantry 89 (main body) has a width of 200 to 400 mm, a thickness of 100 to 200 mm, and a radius of 800 to 1000 mm from the isocenter 5a.

  The X-ray head 10 is a radiation irradiation head that irradiates the irradiation field 5 ′ (affected area 5) with the therapeutic X-ray 3 a. A small electronic linac that emits therapeutic X-rays 3a is provided. A C-type gantry 89 is movably attached via a head circumferential movement mechanism 33. A support frame 102 (including a first swing mechanism 131 (described later) and a second swing mechanism 132 (described later)) is provided.

  The real-time imager 30 irradiates diagnostic X-rays 3b, which are weak fan beam X-rays, onto the treatment field 5 of the patient 4 from two directions (X-ray sources 37A and 37B), and detects transmission images (sensor array 38A). 38B). Then, the detected data is subjected to image processing (imager signal processing device 31) to display a three-dimensional tomographic diagnosis image of the treatment field 5 on the computer screen. The real-time imager 30 is controlled by the system controller 80. The real-time imager 30 includes two sets of X-ray sources 37A and 37B and sensor arrays 38A and 38B that constitute a normal X-ray camera, holding frames 35A and 35B that hold these sets, and holding frames 36A and 36B. It has.

  One end of the holding frame 35A and the holding frame 36A is fixedly held by the support frame 102 (or its peripheral member) of the X-ray head 10, and the other end holds the X-ray source 37A and the sensor array 38A, respectively. Similarly, one end of the holding frame 35B and the holding frame 36B is fixedly held by the support frame 102 (or its peripheral member) of the X-ray head 10, and the other end holds the X-ray source 37B and the sensor array 38B, respectively. ing. Then, in conjunction with the movement of the X-ray head 10, the set of the X-ray sources 37A and 37B and the sensor arrays 38A and 38B can be moved. The holding frames 35A and 35B and the holding frames 36A and 36B are made of a material having high rigidity such as stainless steel, for example.

  The sensor array 38A is disposed in the vicinity of the X-ray head 10 on one side with a plane perpendicular to the virtual circle including the J1 axis as a boundary. As a result, the sensor array 38A is not affected by the powerful X-rays of the X-ray head 10. Then, the perpendicular from the center of the sensor array side plane faces the isocenter 5a, and the X-ray source 37A is disposed on the extended line. Similarly, the sensor array 38B is disposed in the vicinity of the X-ray head 10 on the other side with a plane perpendicular to the virtual circle including the J1 axis as a boundary. Thereby, the sensor array 38B is not affected by the powerful X-rays of the X-ray head 10. The perpendicular from the center of the sensor side plane faces the isocenter 5a, and the X-ray source 37B is disposed on the extended line.

  The sensor arrays 38A and 38B receive (receive light) the diagnostic X-ray 3b that has passed through the patient 4. It is fixedly arranged on the circumference of a circle centering on an isocenter 5a surrounding the diagnostic space in which the patient 4 is arranged, has a large number of long and highly sensitive CdTe sensors, and has a resolution of 0.5 mm. The X-ray irradiation time is 0.01 seconds per shot.

  The distance between each of the X-ray sources 37A and 37B and the sensor arrays 38A and 38B and the isocenter 5a is smaller than the distance between the X-ray head 10 and the isocenter 5a. Since the X-ray source and the sensor array are close to the affected area 5, the image quality of the diagnostic image is improved. Further, the movable range of the X-ray head 10 on the C-type gantry 89 can be widened.

  It is preferable that an angle formed by a perpendicular passing through the isocenter 5a from the center of the surface of the sensor array 38A and a perpendicular passing through the isocenter 5a from the center of the surface of the sensor array 38B is 20 ° to 90 °. More preferably, the angle is 40 ° to 60 °. This is set based on the condition that the X-ray head 10, the X-ray source 37A, and the X-ray source 37B operate accurately without mutual influence and a diagnostic image having sufficient accuracy can be obtained. Is done.

The X-ray source 37A and the X-ray source 37B are on opposite sides of a plane perpendicular to the virtual circle including the J1 axis. The same applies to the sensor array 38A and the isocenter 38B. Thereby, the movement of each part in the body of the patient 4 can be grasped quickly and accurately.
The real-time imager 30 and the C-type gantry 89 are mechanically closely coupled and have a common coordinate reference.

  Since other functions and configurations are the same as those of the real-time imager 74 of the first embodiment, description thereof is omitted.

  By the above three-axis drive (I3, H3), the X-ray head 10 can move in an isocentric manner on the 2/3 spherical shell centered on the isocenter 5a (the X-ray head 10 faces the isocenter 5a). It becomes. Further, by the above two-axis driving (R1, R2), the X-ray head 10 moves in a pseudo non-isocentric manner on the 2/3 spherical shell (the X-ray head 10 is three-dimensional in the vicinity of the isocenter 5a. Can be directed to a desired point in the swinging area 5b (see FIG. 18). Since this pseudo non-isocentric motion is a swing motion around the center of inertia of the X-ray head 10, it is possible to perform a quick motion at each stage as compared with the isocentric motion. The quasi-non-isocentric high-response quick tracking motion enables the head aiming to be followed with high response and high precision even for fast movement such as heartbeat.

  Since the therapeutic bed system 7, the support frame 102, the microwave generator 20, and the driven waveguide system 61 are the same as those in the first embodiment, the description thereof is omitted.

  Further, the X-ray head 10 in FIGS. 3 and 4, the biaxial swing mechanism of the X-ray head 10 in FIGS. 5 and 6, and the rotary RF coupler in FIGS. 7 to 9 have been described in the first embodiment. The explanation is omitted because it is true.

  Next, the control system of the embodiment of the radiotherapy apparatus of the present invention will be described.

FIG. 10 is a block diagram showing a control system of the embodiment of the radiotherapy apparatus of the present invention.
The control system of this embodiment includes a treatment bed system 7, an X-ray head system 8, a real-time imager 30, an imager signal processing device 31, a microwave generator 20, a system controller 80, and a system utility 90. In essence, the system controller 80 controls the entire system.
However, the embodiment is excluding that the real-time imager is the real-time imager 30 and that the isocentric drive mechanism of the X-ray head system 8 includes the C-type gantry 89, the head circumferential movement mechanism 33, and the gantry rotation mechanism 72. Since this is the same as 1, the description thereof is omitted.

  Next, the operation of the embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.

  The operation of the radiotherapy apparatus according to the embodiment is the same as that in the first embodiment except that the real-time imager is the real-time imager 30, the C-type gantry 89, and the head circumferential movement mechanism 33 are used (FIGS. 11 to 17). Therefore, the description thereof is omitted.

  With the radiotherapy apparatus of the present invention, it is possible to obtain the same effect as in the first embodiment.

Example 3
Next, a third embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.
20-21 is the front view and side view which show the structure in 3rd Embodiment of the radiotherapy apparatus which is this invention. Some parts are omitted from the figure. A coordinate 200 indicates a three-dimensional orthogonal coordinate having the X axis, the Y axis, and the Z axis in FIGS.
The radiotherapy apparatus 6 </ b> C includes a treatment bed system 7, an X-ray head 10, a support frame 102, an Ω-type gantry 9, a driven waveguide system 11, a microwave generator 20, a support base 29, and a real-time imager 30. Yes.

The Ω-type gantry 9 includes a gantry tilting mechanism 28, a head circumferential movement mechanism 33, and a wiring 32.
The Ω-type gantry 9 includes a semicircular ring having an arc shape that is an upper half of the therapeutic bed 7-2, and is provided so as to straddle the therapeutic bed 7-2. The gantry tilting axis 26 is an axis in the Y-axis direction that connects both ends and the center of the semicircle, and the center of the circle coincides with the isocenter 5a.

  The gantry tilting mechanism 28 supports the Ω-type gantry 9 so as to be tiltable. The gantry tilting mechanism 28 has a position where the Ω-type gantry 9 stands upright around the gantry tilting axis 26 in the positive direction of the Z-axis is 0 °, + 60 ° (position tilted in the negative X-axis direction) to −210 ° (Z The position can be tilted as indicated by G1 in FIG. 21 within a range of a position tilted in the positive X-axis direction from a position inverted in the negative-axis direction. That is, the Ω-type gantry 9 moves so as to draw a three-quarter sphere (3/4 spherical shell) centered on the isocenter 5a. The Ω-type gantry 9 is made of a material having high rigidity such as stainless steel, and has a width of 200 to 400 mm, a thickness of 20 to 50 mm, and a radius of 800 to 1000 mm from the isocenter 5a.

The head circumferential moving mechanism 33 moves the X-ray head 10 around the semicircular arc of the Ω-type gantry 9 along the Ω-type gantry 9 as indicated by H1 in FIG. A rack and pinion method or a belt method can be adopted.
The wiring 32 is a wiring for control, power supply, etc. used for the X-ray head 10, the real-time imager 30 and the orbital movement mechanism 33.

  By the above three-axis drive (G1, H1), the X-ray head 10 can move in an isocentric manner on the 3/4 spherical shell centered on the isocenter 5a (the X-ray head 10 faces the isocenter 5a). It becomes. Furthermore, by the above-described two-axis drive (R1, R2), the X-ray head 10 moves in a pseudo non-isocentric manner on the 3/4 spherical shell (the X-ray head 10 is three-dimensional in the vicinity of the isocenter 5a. Can be directed to a desired point in the region 5b (see FIG. 20). Since this pseudo non-isocentric motion is a swing motion around the center of inertia of the X-ray head 10, it is possible to perform a quick motion at each stage as compared with the isocentric motion. The quasi-non-isocentric high-response quick tracking motion enables the head aiming to be followed with high response and high precision even for fast movement such as heartbeat.

The driven waveguide system 11 is a waveguide that supplies the microwave generated by the microwave generator 20 to the X-ray head 10. The link arm 12-1, the joint part 14a, the link arm 12-2, the joint part 14b, the link arm 13, the joint part 14c, the link arm 15, the joint part 16, and the X-ray head 10 are connected to each other to form a link mechanism. ing. The joint part 14a, the joint part 14b, the joint part 14c, and the joint part 16 are rotatable around an axis in the X-axis direction. The X-ray head 10 at the end of the link slides along the Ω-type gantry 9 by the head circumferential movement mechanism 33 and is swung around the joint portion 16 by the first swing mechanism 131.
The joint portions 14a, 14b, 14c, and 16 include a rotary RF coupler 50 (described later) that transmits microwaves by axial rotation. The link arms 12-1, 12-2, 13, and 15 include a waveguide 51 (described later), and are electromagnetically communicated by joint portions 14 a to 14 c and 16. Microwaves generated by the microwave generator 20 are supplied to the X-ray head 10 via the joint part 14 a, the link arm 12, the joint part 14 b, the link arm 13, the joint part 14 c, the link arm 15, and the joint part 16. The

Since the therapeutic bed system 7, the support frame 102, and the microwave generator 20 are the same as those in the first embodiment, the description thereof is omitted.
The X-ray head 10 and the real-time imager 30 are the same as those in the second embodiment.

  Further, the X-ray head 10 in FIGS. 3 and 4, the biaxial swing mechanism of the X-ray head 10 in FIGS. 5 and 6, and the rotary RF coupler in FIGS. 7 to 9 have been described in the first embodiment. The explanation is omitted because it is true.

  Next, the control system of the embodiment of the radiotherapy apparatus of the present invention will be described.

FIG. 10 is a block diagram showing a control system of the embodiment of the radiotherapy apparatus of the present invention.
The control system of this embodiment includes a treatment bed system 7, an X-ray head system 8, a real-time imager 30, an imager signal processing device 31, a microwave generator 20, a system controller 80, and a system utility 90. In essence, the system controller 80 controls the entire system.
However, since the isocentric drive mechanism of the X-ray head system 8 is the same as that of the second embodiment except that the Ω-type gantry 9, the head circumferential movement mechanism 33, and the gantry tilting mechanism 28 are included, the description thereof will be given. Omitted.

  Next, the operation of the embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.

  The operation of the embodiment of the radiotherapy apparatus is the same as that of the second embodiment except that the Ω-type gantry 9 and the gantry tilting mechanism 28 are used (including the description of FIGS. 11 to 17). Is omitted.

  With the radiotherapy apparatus of the present invention, it is possible to obtain the same effect as in the second embodiment.

Example 4
Next, a fourth embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.
FIG. 22 is a perspective view showing a configuration in the fourth embodiment of the radiotherapy apparatus according to the present invention. Some parts are omitted from the figure. A coordinate 200 indicates a three-dimensional orthogonal coordinate having the X axis, the Y axis, and the Z axis in FIG.
The radiotherapy apparatus 6D includes a treatment bed system 7, an X-ray head 10, a support frame 102, an Ω-type gantry 9, a driven waveguide system 11 (not shown), a microwave generator 20 (not shown), a support A stand 29 and a real-time imager 30 'are provided.
The configuration of this embodiment is the same as that of Example 3 except that the real-time imager 30 ′ is different.

  The real-time imager 30 ′ includes a rotary drive mechanism 39, holding frames 35A ′ and 35B ′, holding frames 36A ′ and 36B ′, two sets of X-ray sources 37A ′ and 37B ′ and a sensor constituting a normal X-ray camera. It comprises a set of arrays 38A ′, 38B ′.

  The holding frames 35 </ b> A ′ and 35 </ b> B ′ each have one end connected to the X-ray sources 37 </ b> A ′ and 37 </ b> B ′ and the other end connected to the rotation drive mechanism 39. Similarly, the holding frames 36 </ b> A ′ and 36 </ b> B ′ have one end connected to the sensor arrays 38 </ b> A ′ and 38 </ b> B ′ and the other end connected to the rotation drive mechanism 39.

  The sensor array 38 </ b> A ′ is disposed in the vicinity of one side of the X-ray head 10 in the Y-axis direction. The perpendicular from the center of the sensor side plane faces the isocenter 5a, and the X-ray source 37A 'is disposed on the extended line. Similarly, the sensor array 38 </ b> B ′ is disposed in the vicinity of the other side of the X-ray head 10 in the Y-axis direction. The perpendicular from the center of the sensor side plane faces the isocenter 5a, and the X-ray source 37B 'is disposed on the extended line.

  The rotation drive mechanism 39 rotates the real-time imager parallel to the X axis through the isocenter 5a so that the two sets of X-ray sources 37A ′ and 37B ′ and the set of sensor arrays 38A ′ and 38B ′ are at a desired position. The holding frames 35A ′ and 35B ′ and the holding frames 36A ′ and 36B ′ are rotated about the axis Q. At this time, the set of the two sets of X-ray sources 37A ′ and 37B ′ and the sensor arrays 38A ′ and 38B ′ are interlocked with the operation of the X-ray head 10 so as not to disturb the operation of the X-ray head 10. The holding frames 35A ′ and 35B ′ and the holding frames 36A ′ and 36B ′ are rotated.

The set of two sets of X-ray sources 37A ′, 37B ′, and 38B ′ is controlled to maintain a predetermined angle with respect to each other. The angle formed by the sensor array 38A ′ or the sensor array 38B′-isocenter 5a-X-ray head 10 is 60 degrees to 20 degrees. More preferably, it is 45 to 30 degrees. This is based on the condition that the X-ray head 10, the X-ray source 37A ′, and the X-ray source 37B ′ can operate accurately and can obtain a diagnostic image with sufficient accuracy without affecting each other. Is set.
However, the two sets of the X-ray sources 37A ′ and 37B ′ and the sensor arrays 38A ′ and 38B ′ are positioned independently if the visual lines of the X-ray source-sensor array set do not coincide with each other. You may control.

  Other configurations and operations of the real-time imager 30 ′ are the same as those of the real-time imager 30, and thus description thereof is omitted.

  Since the configuration of the present embodiment is the same as that of the third embodiment except that the real-time imager 30 'is different, the description of the other configurations is omitted.

  The operation of this embodiment is the same as that of the third embodiment except that the real-time imager 30 'is different. Therefore, the description is omitted.

With the radiotherapy apparatus of the present invention, it is possible to obtain the same effect as in the third embodiment.
Moreover, since the set of the X-ray source-sensor array is attached to a mechanism different from the X-ray head, the burden on the gantry and the X-ray head is small.

(Example 5)
A fifth embodiment of the radiotherapy apparatus according to the present invention will be described with reference to the accompanying drawings.
FIG. 23 is a perspective view showing the configuration of the fifth embodiment of the radiotherapy apparatus according to the present invention. Some parts are omitted from the figure. A coordinate 200 indicates a three-dimensional orthogonal coordinate having the X axis, the Y axis, and the Z axis in FIG.
The radiotherapy apparatus 6E includes a treatment bed system 7, an X-ray head 10, a support frame 102, an Ω-type gantry 9, a driven waveguide system 11 (not shown), a microwave generator 20 (not shown), a support A stand 29 and a real-time imager 30 'are provided.
The configuration of the present embodiment is the same as that of the third embodiment except that the real-time imager 30 ″ is different.

The Ω-type gantry 9 includes a gantry tilting mechanism 28, a head circumferential movement mechanism 33, and a wiring 32.
The gantry tilting mechanism 28 supports the Ω-type gantry 9 so as to be tiltable. The gantry tilting mechanism 28 sets the Ω-type gantry 9 around the gantry tilting axis 26 to 0 ° as the position where the Ω-type gantry 9 stands upright in the positive direction of the Z axis. Within the range of the position tilted in the positive axial direction), it can be tilted as indicated by G1 ′ in FIG. That is, the Ω-type gantry 9 moves so as to draw a quarter sphere (¼ spherical shell) centering on the isocenter 5a. The Ω-type gantry 9 is made of a material having high rigidity such as stainless steel, and has a width of 200 to 400 mm, a thickness of 20 to 50 mm, and a radius of 800 to 1000 mm from the isocenter 5a.

  Since the head circumferential movement mechanism 33 and the wiring 32 are the same as those in the fourth embodiment, the description thereof is omitted.

  By the above three-axis driving (G1 ′, H1), the X-ray head 10 is moved in an isocentric manner on the ¼ spherical shell centered on the isocenter 5a (the X-ray head 10 faces the isocenter 5a). It becomes possible. Further, by the above-described two-axis drive (R1, R2), the X-ray head 10 moves in a pseudo non-isocentric manner on the ¼ spherical shell (the X-ray head 10 is three-dimensional in the vicinity of the isocenter 5a. Can be directed to a desired point in the region 5b (see FIG. 23). Since this pseudo non-isocentric motion is a swing motion around the center of inertia of the X-ray head 10, it is possible to perform a quick motion at each stage as compared with the isocentric motion. The quasi-non-isocentric high-response quick tracking motion enables the head aiming to be followed with high response and high precision even for fast movement such as heartbeat.

  This real-time imager 30 ″ includes rotational drive mechanisms 39A ″ -1, 39A ″ -2, 39B ″ -1 and 39B ″ -2, and an X-ray source 37A ″ mounted on each of them. -1, X-ray sources 37A ″ -2, 37B ″ -1 and 37B ″ -2, holding frames 36A ″, 36B ″, and sensor arrays 38A ″, 38B ″.

  The holding frames 36A "and 36B" have one end connected to the support frame 102 of the X-ray head 10 and the other end connected to the sensor arrays 38A "and 38B", respectively. That is, the holding frames 36 </ b> A ″ and 36 </ b> B ″ fix the sensor arrays 38 </ b> A ″ and 38 </ b> B ″ to the X-ray head 10 and interlock with the X-ray head 10. The angle formed by the sensor array 98A or the sensor array 98B-isocenter 5a-X-ray head 10 is 90 degrees to 20 degrees. More preferably, it is 60 degrees to 30 degrees.

  The sensor array 38A ″ is disposed in the vicinity of one side of the X-ray head 10 in the Y-axis direction. The perpendicular from the center of the sensor side plane faces the isocenter 5a. Similarly, the sensor array 38 </ b> B ′ is disposed in the vicinity of the other side of the X-ray head 10 in the Y-axis direction. The perpendicular from the center of the sensor side plane faces the isocenter 5a.

  The rotational drive mechanisms 39A "-1, 39A" -2, 39B "-1 and 39B" -2 are provided on the floor surface. The direction of the diagnostic X-rays 3b emitted from the X-ray sources 37A ″ -1, A ″ -2, 37B ″ -1 and 37B ″ -2 mounted on each of them is determined according to a predetermined sensor array. The posture of each X-ray source is controlled so as to be in the direction of 38A ′ or 38B ′.

  Each of the X-ray sources 37A ″ -1, A ″ -2, 37B ″ -1 and 37B ″ -2 is a rotation drive mechanism 39A ″ -1, 39A ″ -2, 39B ″ -1. And 39B ″ -2. A plurality of X-ray sources (in FIG. 23, X-ray sources 37A ″ -1, A ″ -2, 37B ″ -1, and 37B) prepared by the system controller 80 based on the position of the X-ray head 10 are used. The optimum two are selected from “-4” of “-2”. Here, the optimum two satisfy the condition that the diagnostic X-ray 3b is irradiated to the peripheral region including the affected part 5 (near the isocenter 5a) and the transmitted X-rays reach the sensor array. This selection of the optimum X-ray source is performed every time the portal (irradiation direction) of the therapeutic X-ray 3a is changed (not performed in the tracking operation). The two selected X-ray source-sensor array sets are controlled so that their visual lines do not coincide with each other.

  Other configurations and operations of the real-time imager 30 ′ are the same as those of the real-time imager 30, and thus description thereof is omitted.

  Since the configuration of the present embodiment is the same as that of the third embodiment except that the real-time imager 30 'is different, the description of the other configurations is omitted.

  The operation of this embodiment is the same as that of the third embodiment except that the real-time imager 30 'is different. Therefore, the description is omitted.

With the radiotherapy apparatus of the present invention, it is possible to obtain the same effect as in the third embodiment.
Moreover, since the set of the X-ray source-sensor array is attached to a mechanism different from the X-ray head, the burden on the gantry and the X-ray head is small.

  According to the present invention, in addition to the isocentric movement of the entire radiation head part, the head part itself is oscillated in one or two axes around an appropriate center of rotation such as the center of inertia thereof. Thus, non-isocentric irradiation treatment can be performed, and the effect can be obtained at a level completely comparable to that of a completely non-isocentric irradiation treatment apparatus. In addition, it can follow the movement of the irradiation field by breathing or heartbeat at high speed.

  According to the present invention, conditions such as the irradiation position and irradiation time of radiation can be controlled with high accuracy while confirming a treatment field by a non-magnetic type precision inspection apparatus. For this reason, it can be applied to the treatment of the head where the organ itself does not move, and it can also accurately irradiate small lesions of the moving organ such as the heart and lungs. The application can be expanded.

  According to the present invention, unlike a cantilever type robot arm that is problematic in terms of rigidity, a radiation head support structure having high strength and high rigidity can be adopted, and high absolute accuracy can be mechanically guaranteed. It becomes possible. For this reason, the required efficient treatment becomes possible.

  The application of a general-purpose industrial robot arm having an excessive degree of freedom far exceeding the degree of freedom required for non-isocentric irradiation treatment is problematic in terms of patient safety. That is, in the event of an accident such as a malfunction of the robot arm, the robot arm or the radiation irradiation head at the tip of the robot arm may come into contact with the patient, causing traumatic harm to the patient. On the other hand, the movable range is limited, and absolute safety for the patient can be ensured.

  In the prior art, the irradiation field cannot be monitored in real time during the irradiation treatment, and irradiation based on the estimation is forced. However, according to the present invention, a normal X-ray camera, X-ray CT, PET, DSA is used. With such an imager, it becomes possible to monitor the irradiation field in real time during irradiation treatment, and irradiation treatment with high reliability and safety becomes possible.

  Further, image tracking is performed based on the above-described irradiation field image obtained in real time, and follow-up irradiation to a moving irradiation field is possible.

  The man-machine interface with the doctor shown in the embodiment of the present invention enables radiotherapy with excellent safety and reliability.

It is a front view which shows the structure in 1st Embodiment of the radiotherapy apparatus which is this invention. It is a side view which shows the structure in 1st Embodiment of the radiotherapy apparatus which is this invention. It is a figure which shows the structure of the X-ray head applied to the radiotherapy apparatus which is this invention. However, (a) Overall view, (b) AA sectional view of (a), (c) BB sectional view of (a). FIG. 4 is an enlarged view of the vicinity of the electron gun and the acceleration tube of FIG. It is a perspective view which shows the X-ray head supported by the support frame. It is a figure which shows the structure of the biaxial swing mechanism of a support frame. However, (a) overall, (b) S1 swing drive servomotor, (c), joint, (d) S2 swing drive servomotor, and (e) rotary RF coupler. It is a figure which shows the structure of the joint part which has a rotary RF coupler inside. It is a perspective view which shows the detail of a structure of the rotary RF coupler shown in FIG. (A) It is sectional drawing which shows the detail of the rotary RF coupler of FIG. (B) An example of the mode of the microwave in a rotary RF coupler is shown. It is a block diagram which shows the control system of embodiment of the radiotherapy apparatus which is this invention. It is a timing chart in operation | movement of embodiment of the radiotherapy apparatus which is this invention. However, (a) timing of operation for processing a diagnostic image, (b) timing of image tracking calculation based on the diagnostic image after processing and swinging operation of the X-ray head, and (c) timing of irradiation of therapeutic X-rays. . It is a perspective view which shows the mode of the radiotherapy by an X-ray head. It is a figure explaining a mode that a treatment X-ray is irradiated, swinging an X-ray head, and shows the AA cross section in FIG. It is a figure explaining a mode that treatment X-ray is irradiated, swinging an X-ray head, and shows a BB section in FIG. (A)-(f) It is a flowchart which shows the procedure of a pseudo | non-isocentric treatment by the display of a display. It is a figure which shows the relationship between the affected part, a definition area | region, and the outline by pattern matching. However, (a) the relationship between the affected area and the definition area, and (b) to (e) the relationship between the affected area and the contour line are shown. It is a graph which shows an example of the brightness distribution in a diagnostic image. It is a front view which shows the structure in 2nd Embodiment of the radiotherapy apparatus which is this invention. It is a side view which shows the structure in 2nd Embodiment of the radiotherapy apparatus which is this invention. It is a front view which shows the structure in 3rd Embodiment of the radiotherapy apparatus which is this invention. It is a side view which shows the structure in 3rd Embodiment of the radiotherapy apparatus which is this invention. It is a perspective view which shows the structure of 4th Embodiment of the radiotherapy apparatus which is this invention. It is a perspective view which shows the structure of 5th Embodiment of the radiotherapy apparatus which is this invention.

Explanation of symbols

2, 2a, 2b Electric field lines 3a Therapeutic X-ray 3b Diagnostic X-ray 4 Patient 5 Affected part 5 'Irradiation field 5-1 Definition area 5-2 (a, b, c) Contour line 5a Isocenter 5b Swing area 6 , 6A, 6B, 6C, 6D, 6E Radiation therapy device 7 Treatment bed system 7-1 Bed drive system 7-2 Treatment bed 7-3 Patient fixation device 8 X-ray head system 9 Ω type gantry 10 X-ray head 11 , 61, driven waveguide system 12, 13, 15, 62 (-1 to 2), 63, 65 link arm 14a, 14b, 14c, 16, 64a, 64b, 64c, 66 joint 20 microwave generator 21 Circulator 22 Dummy load 26 Gantry tilting axis 28 Gantry tilting mechanism 29 Support base 30 (',''), 74 Real-time imager 31 Imager signal processing 32 wiring 33 head circumferential moving mechanism 35A ( ',''), 35B (', ''), 36A ( ',''), 36B (
',''), 76A, 76B Holding frame 37A ('), 37B ('), 37A "-1-2, 37B" -1-2,
77A, 77B X-ray source 38A (',''), 38B (', ''), 78A, 78B Sensor array 39, 39A ''-1-2, 39B ''-1-2 Rotation drive mechanism 50, 50A , 50B Rotary RF coupler 51 Waveguide 52 RF window 53, 54 Flange joint 55a, 55b Waveguide 56, 57 Rotating member 58 Bearing 59 λ / 4 wavelength choke 67, 67-1, 67-2 Support frame 66 Joint portion 68 (-1 to 2) Holding part 69 O-type gantry 70 Ring circular movement mechanism 71, 71-1, 71-2 O-type drive ring 72 Gantry rotation mechanism 72-1 Base part 72-2 Rotation part 72-3 Drive part 73 Gantry rotation mechanism 75 Protection plate 76, 76A, 76B Holding frame 77, 77A, 77B X-ray source 78, 78A, 78B Sensor array 80 System controller 82 On Part support mechanism 82-1 base part 82-2 rotating part 89 C-type gantry 90 system utility 95 rotating drive mechanism 99 rotating drum (treatment gantry)
DESCRIPTION OF SYMBOLS 101 Head cover 102 Support frame 102a Bracket 103 Insulating glass 104 Electron gun 105 Cathode 106 Anode 107, 108 Exhaust pipe 109 Buncher cavity 110 Acceleration pipe 111a Side couple cavity 111b Acceleration cavity 111c Center hole 112 Ion pump 114 High voltage connection terminal 116 Electric circuit / cooling Water circuit 119 Target exhaust chamber 120 Output section 121 Target 122 Cooling plate 123 Primary collimator 124 Flattening filter 125 Secondary collimator 126 Ionization chamber 131 First swing mechanism 131a Drive shaft 131b S1 swing drive servomotor 132 Second swing Mechanism 132a Drive shaft 132b S2 swing drive servo motor 133 bearing 200 coordinates S1 first swing shaft S2 second swing shaft DESCRIPTION OF SYMBOLS 1 1st swing direction R2 2nd swing direction J1 1st rotating shaft J2 2nd rotating shaft I1 O type gantry rotating direction I2 O type drive ring rotating direction I3 C type gantry rotating direction G1 Arc guide rail moving direction H1, H3 X-ray head movement direction Q Real-time imager rotation axis

Claims (16)

O-type gantry,
A radiation irradiation head that is movably provided in the O-type gantry and irradiates therapeutic radiation to a treatment field of a subject;
An X-ray source that is movably provided in the O-type gantry and irradiates diagnostic X-rays to the treatment field of the subject;
A sensor array that is movably provided on the O-type gantry, detects transmitted X-rays of the diagnostic X-rays that have passed through the subject, and outputs them as diagnostic image data;
The sensor array is provided at a target position across the radiation irradiation head, and moves on the O-type gantry in conjunction with the movement of the radiation irradiation head.
The X-ray source moves in conjunction with the movement of the sensor array. The radiation therapy apparatus according to claim 1, wherein the radiation head, the X-ray source, and the sensor array are provided inside a ring of the O-type gantry. The radiation therapy apparatus according to claim 1, wherein the sensor array is provided in the vicinity of the radiation irradiation head. The radiotherapy apparatus according to claim 3, wherein the sensor array is provided on both sides of the radiation irradiation head. The radiotherapy apparatus according to any one of claims 1 to 4, further comprising a head circumferential movement mechanism that moves the radiation irradiation head along the O-type gantry. The radiotherapy apparatus according to claim 1, wherein a distance between each of the X-ray source and the sensor array and the isocenter is smaller than a distance between the radiation irradiation head and the isocenter. The radiotherapy apparatus according to any one of claims 1 to 8, wherein the X-ray source and the sensor array are in a symmetrical position with respect to an isocenter. A control unit;
An image processing unit that generates the diagnostic image of the treatment field based on the diagnostic image data; and
The radiation irradiation head is movably connected to the O-type gantry and swings the radiation irradiation head so that the therapeutic radiation emitted from the radiation irradiation head follows the movement of the treatment field. Equipped with a swing mechanism,
The control unit is configured so that the irradiation field of the radiation irradiation head tracks the treatment field based on the diagnostic image, the position of the radiation irradiation head, and the swinging state of the radiation irradiation head. The position of the head swing mechanism is controlled, and after the position control of the head swing mechanism, the radiation irradiation head is controlled so as to irradiate the therapeutic radiation from the radiation irradiation head. The radiotherapy apparatus of claim | item. The controller is
Based on a predesignated image pattern on the diagnostic image indicating the treatment field,
Calculating first coordinates as coordinates of the treatment field in the diagnostic image;
Based on the position of the radiation irradiation head and the swinging state of the radiation irradiation head, the second coordinates as the coordinates of the irradiation field are calculated,
The radiotherapy apparatus according to claim 8, wherein position control of the head swing mechanism is performed based on the first coordinate and the second coordinate such that the treatment field is included in the irradiation field. The radiotherapy apparatus according to claim 8 or 9, wherein the control unit performs position control of the head swing mechanism and control of the radiation irradiation head at predetermined time intervals. The radiotherapy apparatus according to any one of claims 8 to 10, wherein the head swing mechanism swings the radiation irradiation head around two axes orthogonal to each other. The radiotherapy apparatus according to any one of claims 8 to 11, further comprising a gantry rotation mechanism that rotates the O-type gantry around a vertical axis. The radiotherapy apparatus according to any one of claims 1 to 12, wherein the O-type gantry is replaced with any one of a C-type gantry, an Ω-type gantry, and an L-type gantry. A microwave generator for generating microwaves;
14. The waveguide according to claim 1, further comprising: a waveguide having one end connected to the microwave generation device, the other end connected to the radiation irradiation head, and guiding the microwave to the radiation irradiation head. The radiotherapy apparatus as described. The microwave belongs to C band,
The radiotherapy apparatus according to claim 14, wherein the radiation irradiation head includes an acceleration tube that accelerates an electron beam with the microwave. The microwave belongs to the X band,
The radiotherapy apparatus according to claim 14, wherein the radiation irradiation head includes an acceleration tube that accelerates an electron beam with the microwave.

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