JP3746744B2 - Radiation therapy equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiotherapy apparatus suitable for, for example, radiotherapy of a tumor site by a stereotactic multi-orbital irradiation method.
[0002]
[Prior art]
As one of the radiotherapy methods, there is a stereotactic multi-orbital irradiation method that increases the therapeutic effect by intensively irradiating the affected area with radiation from multiple directions and can reduce the exposure dose to the surrounding tissue to the minimum.
[0003]
This stereotactic multi-orbital irradiation method is used for primary benign brain tumors, single metastatic brain tumors of 3 cm or less, small lesions in the brain such as skull base metastases that are difficult to operate, arterial malformations or venous malformations It is effective for the treatment of affected areas such as
[0004]
As a radiotherapy apparatus capable of performing such a stereotactic multi-orbital irradiation method, there is conventionally known a device that irradiates radiation after positioning an irradiation head with respect to an affected part using a positioning means. Since radiation is not irradiated after confirming the position of the lesion by directly looking at the irradiation field, high-precision irradiation of radiation cannot be expected.
[0005]
In contrast, Japanese Patent Publication No. 6-502330 and Japanese Patent Publication No. 8-504347 disclose a combination of a radiotherapy apparatus and an X-ray CT apparatus by incorporating a linear accelerator in the rotating drum of the X-ray CT apparatus. The configuration is disclosed. With this configuration, it is possible to perform radiation irradiation while confirming an image of the irradiation field.
[0006]
[Problems to be solved by the invention]
However, since these apparatuses have a structure in which a linear accelerator is incorporated in a rotating drum of an X-ray CT apparatus, the irradiation is limited to only about one rotation axis and is limited to isocentric irradiation.
[0007]
The objective of this invention is providing the radiotherapy apparatus which has the outstanding therapeutic performance.
[0008]
[Means for Solving the Problems]
To achieve the above object, the present invention provides an electron gun, a linear accelerator, and a target. Gimbal mechanism that swings the therapeutic radiation generator and the therapeutic radiation generator An irradiation head, a support moving mechanism for supporting and moving the irradiation head on a predetermined spherical coordinate, and a micro to be supplied to the irradiation head Wave Occurs, stationary position A microwave oscillator arranged at one end, and a waveguide section having one end electromagnetically connected to the microwave oscillator and the other end electromagnetically connected to the linear accelerator And Radiation therapy equipment In , The waveguide of the waveguide unit mounted on the gimbal mechanism and the waveguide of the waveguide unit from the microwave oscillator are connected by a flexible waveguide. The
[0009]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
As shown in FIGS. 1 to 3, the radiotherapy apparatus 6 according to the present embodiment delivers therapeutic radiation to a bed 7 having a top plate 8 on which a patient 4 is placed and an irradiation field 5 that can be set on the patient 4. X-ray CT apparatus for acquiring a tomographic image of an irradiation head 10 for irradiation and an irradiation field 5 as an affected part Set 3 0.
[0010]
The top plate 8 can be moved in three axes, that is, a bed longitudinal direction (X-axis direction), a bed width direction (Y-axis direction), and a bed vertical direction (Z-axis direction) by a driving mechanism built in the bed 7. Further, the position of the top board 8 is adjusted by the top board 8 integrated and controlled by the system control device 80 so that the irradiation field 5 as the affected part is located at the isocenter 5a based on the captured image data of the image acquisition device. (See FIG. 9). Top plate 8 is X-ray CT equipment Place A material and shape suitable for an image acquisition apparatus such as a PET (Positron Emission Tomography) apparatus are selected.
[0011]
The irradiation head 10 is rotated by (G1) by the tilting shaft 26, the orbital movement mechanism 68, and the first and second swing mechanisms 131, 132 by a half ball (1 / 2), the guide rail 9 is movably supported so that an arbitrary irradiation position can be obtained. As shown in FIG. 2, the orbiting movement mechanism 68 moves the irradiation head 10 around the guide rail 9 (H1), and a rack and pinion method or a belt method can be adopted. As shown in FIG. 10 and FIGS. 11A to 11D, the first swing mechanism 131 includes a servo motor that swings the irradiation head 10 around the first axis S1, and the second swing is made. The mechanism 132 includes a servo motor that swings the irradiation head 10 about the second axis S2.
[0012]
The irradiation head 10 is connected to the rotary RF coupler 16 of the waveguide system 11 shown in FIG. It is connected to a microwave generation source 70 (klystron) by a waveguide 51 and a rotary RF coupler 50 on the gimbal mechanism shown in FIG.
[0013]
The first swing mechanism 131 is a mechanism for swinging (S1) the irradiation head 10 around the rotary RF coupler 16 on the guide rail 9, as shown in FIGS. The rotary RF coupler 16 is provided on an axis substantially passing through the center of inertia of the irradiation head 10 so that the inertial force when the irradiation head 10 swings is reduced.
[0014]
As shown in FIGS. 1 and 11A, the second swing mechanism 132 is a mechanism that swings (S2) the irradiation head 10 around the rotary RF couplers 50A and 50B on the guide rail 9. The rotary RF couplers 50A and 50B are provided on an axis that substantially passes through the center of inertia of the irradiation head 10 so that the inertial force when the irradiation head 10 swings becomes small. Incidentally, the irradiation head 10 has a total length of 500 to 600 mm, a width of 500 mm × a depth of 300 mm, and a weight of 60 to 80 kg.
[0015]
As shown in FIGS. 2 and 3, the guide rail 9 is composed of a semicircular ring having an arc shape that is half the upper half of the top plate 8, and is provided so as to straddle the top plate 8 in the width direction. The guide rail 9 is supported to be tiltable by a tilting mechanism. The tilting mechanism tilts the guide rail 9 around the tilting shaft 26 in FIG. 2 within a range of 0 ° to 180 ° (G1) as shown in FIG. The guide rail 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 from the isocenter 5a of 800 to 1000 mm.
[0016]
The above-described two-axis drive (G1, H1) allows the irradiation head 10 to move in an isocentric manner on a ½ spherical shell centered on the isocenter 5a. Furthermore, the above-described two-axis drive (S1, S2) enables the irradiation head 10 to move in a pseudo non-isocentric manner on the ¼ spherical shell. This pseudo non-isocentric operation is a swinging motion around the center of inertia of the irradiation head 10 and thus is much faster than the isocentric operation. The pseudo-non-isocentric high-response quick tracking motion enables the irradiation head aiming to be followed with high response and precision even for fast movement such as heartbeat.
[0017]
The X-ray CT apparatus 30 is supported in a posture inclined at a predetermined angle (for example, an inclination of 20 ° to 30 ° with respect to the vertical axis) by the image acquisition device tilting mechanism 20 shown in FIG. When the image acquisition apparatus tilt mechanism 20 is driven, the X-ray CT apparatus 30 tilts (K1) about the axis, and the irradiation angle of the image acquisition X-ray 3b can be changed. The X-ray CT apparatus 30 and the guide rail 9 are mechanically closely coupled and have a common coordinate reference.
[0018]
The X-ray CT apparatus 30 is controlled so that the guide rail 9 and the irradiation head 10 do not interfere with each other. When using an X-ray fluoroscopy device as an image acquisition device, there is a problem in terms of resolution and contrast, and it is better to embed a small gold plate near the irradiation field and mark the irradiation field as a reference using this as a marker. .
[0019]
The SAD (Source Axis Distance) shown in FIG. 2 corresponds to the distance from the isocenter 5a to the target 121 (see FIG. 4A) in the irradiation head. In this embodiment, the standard SAD1 is set to 80 cm to 100 cm.
[0020]
To irradiate following the movement of the irradiation field as shown in FIGS. 6, 7, and 8, the shift amounts DV1, DV2 obtained from the image data and a predetermined formula are used to determine the position around the S1 swing drive shaft. A minute displacement angle θ1 and a minute displacement angle θ2 around the S2 swing drive axis are obtained. The driving of the swing mechanisms 131 and 132 is controlled according to the calculation result, and the irradiation head 10 is swung at a high speed by the minute displacement angle θ1 and the minute displacement angle θ2. As a result, the aim of the irradiation head 10 quickly and rapidly responds to the affected area 5 such as a tumor moving under the influence of the movement and state of the organ such as breathing and heartbeat below the neck, peristalsis, and urine volume in the bladder. In addition, it becomes possible to irradiate radiation with high accuracy.
[0021]
Reference numerals 14a to 14c and 16 in FIG. 2 denote a waveguide system having a rotary RF coupler 50 for transmitting an acceleration microwave by axial rotation. As shown in FIG. 12, a waveguide 51 is provided in the link arms 13 and 15, and the waveguide 51 is electromagnetically communicated by a rotary RF coupler 50 in the joint portions 14 a to 14 c and 16. As shown in FIG. 13, the rotary RF coupler 50 is connected to each of the waveguides 51 by flange joints 53 and 54. Reference numeral 21 is a circulator, and 22 is a dummy load.
[0022]
Further, as shown in FIG. 14, the waveguides 55a and 55b of the waveguide 51 communicate with the rotation space surrounded by the rotation members 56 and 57 of the rotary RF coupler 50, and this is the in-tube mode 2a (2b). Microwave is guided. In the figure, reference numeral 58 denotes a bearing, and reference numeral 59 denotes a λ / 4 wavelength choke. By such a combination of the rotary RF coupler 50 and the waveguide 51, the acceleration microwave can be smoothly supplied to the irradiation head 10 moving from the acceleration microwave source 70 such as a klystron fixed to the floor or the like. .
[0023]
The waveguide system 11 includes a first joint portion 14a, a first arm 12, a second joint portion 14b, a second arm 13, a third joint portion 14c, a third arm 15, and a fourth joint. This is a link mechanism in which the portion 16 and the irradiation head 10 are connected to each other. Only the first joint portion 14a is provided along the Y axis, and the second to fourth joint portions 14b, 14c, and 16 are provided along the X axis, respectively. The irradiation head 10 at the tip of the link is slid along the guide rail 9 by the circular movement mechanism 68 and is swung around the fourth joint portion 16 by the first swing mechanism 131. Yes.
[0024]
The system controller 80 is an X-ray CT device. Set 3 When CT tomographic diagnostic image data of the irradiation field 5 is input from 0, the irradiation field 5 in the isocenter 5a is controlled by controlling the rotation movement mechanism 68, the rail tilting mechanism, and the top plate 8 based on this data. Aim the irradiation head 10 at the same time.
[0025]
Further, when the irradiation field 5 moves, the system control device 80 sets the X-ray CT apparatus. Set 3 Calculation for image tracking is performed based on input data from 0, and the irradiation head 10 is swung by controlling the operations of the first and second swing mechanisms 131 and 132 based on the calculation result. During the swinging operation of the irradiation head 10, the interlock works so that no radiation is irradiated, so that the exposure dose in the vicinity can be minimized.
[0026]
In this embodiment, an X-ray CT apparatus is used as an inspection apparatus. Set 3 Although the case where 0 is combined with a radiotherapy apparatus has been described, the present invention is not limited to this, and other non-magnetic type image acquisition such as an X-ray fluoroscopic apparatus and PET (Positron Emission Tomography) in special applications. It is possible to combine the device with a radiotherapy device.
[0027]
In the case of a normal type fluoroscope, two or more cameras having different lines of sight are required. In addition, since soft tissues with low contrast cannot be imaged, the irradiation field can be positioned in advance using an X-ray CT apparatus, MRI, or the like based on landmarks with high contrast such as bone tissue, or small gold It is necessary to devise a technique such as embedding a plate or the like in the vicinity of the irradiation field to be used as a marker, or image enhancement by contrast agent or differential image processing such as DSA (Digital Subtraction Angiography). In addition, real-time imaging is required for X-ray CT apparatuses and PET, and high-speed real-time image reconstruction calculation is required.
[0028]
Next, the irradiation head 10 will be described in detail with reference to FIGS. 4A to 4C, FIGS. 5 and 10, and FIGS. 11A to 11D.
[0029]
The irradiation head 10 is composed of a small electronic linac that has an electron energy of 4 MeV to 10 MeV and generates X-rays 3a for treatment, and is within the range of a half spherical shell in the upper half rear part centering on the isocenter 5a. The guide rail 9 is movably supported and connected to the rotary RF coupler 16 of the waveguide system 11 so as to be capable of swinging so that radiation can be irradiated from multiple directions by moving in three dimensions.
[0030]
The irradiation head 10 has a main body covered with a cover 101, and an emission part 120 for emitting radiation is attached to the distal end side of the main body. An electric circuit / cooling water circuit 116, an accelerator 110, an RF window 52, a waveguide 51, a part of a rotary RF coupler 50B, an exhaust pipe 107, a vacuum pump 112, and a target exhaust chamber are disposed in a cover 101 that covers the irradiation head main body. 119, a target 121, and a cooling plate 122 are provided.
[0031]
A cable (not shown) connected from the insulator 103 at the tail of the accelerator to an external power source is introduced into the 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 space between the cathode 105 and the anode 106 is exhausted by an exhaust pipe 107 communicating with a vacuum pump 112. The power source of the electron gun 104 is controlled by the system controller 80. The electron gun 104 continues from the accelerator 110 to the accelerator 110 and further from the accelerator 110 to the emission unit 120. Note that the length from the insulator 103 to the tip of the accelerator 110 is about 360 mm.
[0032]
As shown in FIG. 5, the central hole of the anode 106 of the electron gun 104 communicates with the buncher cavity 109 of the accelerator 110. The accelerator 110 accelerates the electron beam emitted from the electron gun 104 and causes a high-energy electron beam to collide with the X-ray target 121. Inside the accelerator 110, an acceleration cavity 111b having a central hole for passing an electron beam is connected. The acceleration cavity 111b communicates with a pair of left and right side exhaust pipes 108 via side-coupled cavities 111a, and the pair of left and right side exhaust pipes 108 are connected to a vacuum pump 112 to be evacuated. . That is, the inside of the accelerator 110 is evacuated by the vacuum pump 112 via the side-coupled cavity 111a and the side exhaust pipe 108 on the side.
[0033]
A waveguide 51 communicates with the accelerator 110. The waveguide 51 communicates with the microwave oscillator 70 through a ceramic RF window 52 and rotary RF couplers 50A and 50B. The RF window 52 is an entrance through which the microwave is introduced into the accelerator 110 while preventing leakage of SF6 gas sealed in the waveguide 51. The microwave oscillator 70 is of a klystron type with excellent output stability. A power supply circuit of the microwave oscillator 70 is connected to the system controller 80.
[0034]
The emission unit 120 is provided at the tip of the irradiation head main body covered with the cover 101, and includes an X-ray target 121, a target cooling plate 122, a primary collimator 123, and a flattening filter 124. From the electron gun 104 through the accelerator 110 to the flattening filter 124, they are arranged in series along the optical axis of the electron beam, and the accelerated electron beam enters the target 121 of the emitting unit 120 through the target exhaust chamber 119. It is like that.
[0035]
The X-ray target 121 is susceptible to thermal damage because high-energy accelerated electrons are incident and emit braking radiation X-rays, and a cooling plate 122 is attached and cooled as a countermeasure. Note that the target 121 is made of a refractory metal such as tungsten or tantalum or an alloy thereof.
[0036]
The primary collimator 123 is made of a material having excellent shielding properties against radiation such as tungsten and generating less thermal neutrons, and guides X-rays from the target 121 to the flattening filter 124.
[0037]
The flattening filter 124 is for averaging the intensity of the X-rays emitted from the target 121 to obtain the therapeutic radiation 3a having a uniform dose distribution.
[0038]
Further, a secondary collimator 125 and a dose measuring ionization chamber 126 are attached to the distal end side of the emitting unit 120. The secondary collimator 125 is made of a highly shielding material such as tungsten that cannot transmit the therapeutic X-rays 3a, and the therapeutic radiation 3a is sent to the dosimetry ionization chamber 126 through the hollow portion. Yes. The secondary collimator 125 is detachably screwed into the end surface portion of the primary collimator 123.
[0039]
The dose measurement ionization chamber 126 is an ionization chamber attached to the tip of the secondary collimator 125 and filled with a gas of a predetermined component, and connected to a detection circuit (not shown) for detecting discharge charges. 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 irradiation head 10 based on the input signal from the dose measurement ionization chamber 126 and stores it in the memory as treatment dose data received by the patient 4. ing.
[0040]
Next, the control system of the present embodiment device will be described with reference to FIG.
[0041]
The control system of the present embodiment device includes a top plate 8, an irradiation head 10, an X-ray CT device 30, a signal processing device 31, a microwave oscillator 70, a system control device 80, and a system utility 90, and the system control device 80 as a whole. It is a system configuration that controls and controls.
[0042]
The system control device 80 includes a system control computer, a system management algorithm, an image tracking algorithm, a treatment planning algorithm, a treatment management algorithm, a graphical user interface, a treatment database, an interlock algorithm, and a system monitor. These system blocks are connected to each other so that input / output signals can be exchanged.
[0043]
The X-ray CT apparatus 30 is connected to the system control apparatus 80 via the signal processing apparatus 31. As a result, image diagnosis is performed in real time during treatment, and a doctor can perform treatment while viewing the diagnostic image displayed on the computer display.
[0044]
The microwave oscillator 70 includes a klystron modulator and linac system controller, a klystron, and an RF driver. The klystron is connected to the irradiation head 10 via the waveguide system 11 and is a supply source for supplying microwaves to the accelerator 110.
[0045]
Each driver of the isocentric drive mechanism and the swing drive mechanism of the irradiation head 10 is connected to the system control device 80, and the circular drive 68 of the irradiation head 10 at the time of isocentric irradiation and the irradiation head at the time of pseudo non-isocentric irradiation Each of the ten biaxial swing drives is controlled.
[0046]
Next, the two-axis swing mechanism of the irradiation head will be described in detail with reference to FIGS.
[0047]
As shown in FIG. 10, the irradiation head cover 101 is supported by a support frame 102 having a gimbal structure. The support frame 102 is attached to the position coordinates through which the S1 axis and the S2 axis including the center of inertia of the irradiation head 10 pass.
[0048]
As shown in FIG. 11A, the support frame 102 includes a rotary RF coupler 16 of the waveguide system 11, a pair of rotary RF couplers 50A and 50B, an S1 swing drive servomotor 131, and an S2 swing drive servomotor 132. Are attached to each side.
[0049]
The rotary RF coupler 16 of the waveguide system 11 is attached to the center of one long side of the support frame 102, and the drive shaft 131 a of the S1 swing drive servomotor 131 faces the long side of the frame 102 so as to face this. It is attached to the center (see FIG. 11B). When the servo motor drive shaft 131a is rotationally driven, the irradiation head 10 swings around the S1 drive shaft as shown in FIG.
[0050]
Further, the pair of rotary RF couplers 50A and 50B are attached to the center of one short side of the support frame 102 (see FIG. 11D), and the drive shaft 132a of the S2 swing drive servomotor 132 faces this. Is attached to the center of the opposing short side of the frame 102 (see FIG. 11C). That is, the main body of the servo motor 132 is fixedly supported by the bracket 102a on the support frame side, and the motor drive shaft 132a is rotatably supported by the support frame 102 via the bearing 133. When the servo motor drive shaft 132a is rotationally driven, the irradiation head 10 swings around the S2 drive shaft as shown in FIG.
[0051]
As shown in FIG. 11A, a waveguide 51 is provided in each of the link arms 13 and 15 of the waveguide system 11, a rotary RF coupler 50 is provided in each of the joint portions 14 and 16, and a pair of Microwaves are introduced into the accelerator 110 in the irradiation head through the rotary RF couplers 50A and 50B.
[0052]
As shown in FIGS. 6 to 8, using the shift amounts DV1 and DV2 obtained from the diagnostic imaging data and a predetermined formula, the minute displacement angle θ1 around the S1 swing drive axis and the minute displacement around the S2 swing drive axis Each of the angles θ2 is obtained, and the driving of the swing mechanisms 131 and 132 is controlled according to the calculation results, so that the irradiation head 10 is swung at high speed by the minute displacement angle θ1 and the minute displacement angle θ2. Then, radiation is emitted from the irradiation head 10 during the swinging motion. As a result, the aim of the irradiation head 10 can be promptly and highly responsive to the affected part 5 such as a tumor moving under the influence of the movement and state of the organ, such as breathing, heartbeat, peristalsis, and urine volume in the bladder. Follow. Incidentally, the irradiation head 10 can be swung at a high speed within 0.1 seconds including the processing time of the diagnostic image, and can quickly follow the movement of the irradiation field (affected area).
[0053]
Next, with reference to the timing chart of FIG. 15, the operation of the radiotherapy apparatus according to the present embodiment is particularly effective in preventing the influence of direct rays, leakage lines, and scattered rays of therapeutic radiation on the image acquisition device detector. A method for realizing time-division real-time irradiation of therapeutic radiation will be described.
[0054]
First, when the main switch of the radiotherapy apparatus 6 is turned on, the power of the treatment bed system 7, the irradiation head 10, the X-ray CT apparatus 30, the microwave oscillator 70, the system control apparatus 80, and the system utility 90 is in a standby state. The treatment couch system 7 is activated, the patient 4 is moved into the treatment area together with the top plate 8, the image acquisition device is activated, and the top plate 8 is moved so that the affected part 5 coincides with the isocenter 5a of the treatment device. Match. After this isocentric alignment is completed, real-time image diagnosis by the X-ray CT apparatus 30 and radiation therapy by the irradiation head 10 are started.
[0055]
At time t <b> 0 in FIG. 15, the X-ray CT apparatus 30 starts irradiating the image acquisition X-ray 3 b toward the irradiation field 5. The transmitted image is detected as an acquired image at times t0 to t1 shown in FIG. In order to minimize the exposure, the irradiation time of the image acquisition X-ray 3b is also limited to the time t0 to t1. In order to prevent direct rays, leakage rays, and scattered rays of the therapeutic radiation 3a from affecting the detector at least at times t0 to t1 during which the image acquisition X-ray 3b is irradiated, the irradiation head 10 is Interlocking is performed so as not to emit the therapeutic radiation 3a.
[0056]
The detected acquired image is captured (recorded) at time t1 to t2. Information such as the tracking image data of the acquired acquired image is processed by the signal processing device 31 and the system control device 80 at time t2 to t3, and the processed image is displayed on the display. Also, information processed as a result of this image tracking calculation is sent to the swing mechanisms 131 and 132 as position correction data. Then, the same cycle from image acquisition to image processing as from time t0 to t3 is repeated after time t3.
[0057]
While the next image detection and image capture are performed from time t3 to time t5, the swing servos of the swing mechanisms 131 and 132 are based on the result of the image tracking calculation sent as position correction data. Swing angles θ1 and θ2 are driven. The irradiation head 10 is interlocked in consideration of safety so as not to irradiate the therapeutic radiation 3a during the time t3 to t5 during which the head swing mechanisms 131 and 132 are driven.
[0058]
At time t5 when the head swing mechanisms 131 and 132 are stopped, the interlock of the irradiation head 10 is released, and the therapeutic radiation 3a starts to be irradiated. The irradiation time of the therapeutic radiation 3a is time t5 to t6 until the swing mechanism 131, 132 is driven next. Further, in synchronization with the times t5 to t6, the image tracking calculation of the tracking image data of the acquired image acquired during the times t3 to t5 is executed. At time t6, the third image detection and the second swing servo drive are started, and the second image tracking calculation and the first irradiation with the therapeutic radiation 3a are completed.
[0059]
After the irradiation of the therapeutic radiation 3a is stopped, the irradiation of the image acquisition X-ray 3b is started at time t6, and the process proceeds to the next acquired image processing cycle starting from time t6. At time t8 after the third image capture from time t0, the interlock of the irradiation head 10 is released, and the second irradiation of the therapeutic radiation 3a is resumed.
[0060]
As described above, the image processing cycle and the swing and irradiation cycle overlap each other. The cycle of driving the swing head and irradiating the therapeutic radiation 3a performed during a certain image processing cycle is performed based on information on the cycle of the image processing performed immediately before this image processing cycle. It is.
[0061]
When following a fast movement such as a heartbeat, the irradiation head 1 starts from the start of image detection. 0 The time t0 to t6 from when the head is swung to the end of the irradiation with the therapeutic radiation 3a is set to be within 0.1 seconds. Therefore, the time chart shown in FIG. 15 shows a case where one cycle of image processing and one cycle of swing and irradiation are each 0.05 seconds. Therefore, the time in the time chart shown in FIG. 15 is an example, and may be implemented at other time intervals.
[0062]
In addition, when an abnormality occurs in image acquisition or image tracking calculation, the safety is improved by applying an interlock so that the irradiation of the therapeutic radiation 3a is stopped at that time. Note that the radiation therapy apparatus 6 according to the present embodiment is configured to irradiate the therapeutic radiation 3a after confirming that the irradiation head 10 has been swung and positioned normally.
[0063]
As described above, in the radiotherapy apparatus 6 of the present embodiment, the image detection cycle, the image capture cycle, the image tracking calculation cycle, the head swing control cycle based on the cycle, and the irradiation cycle of the therapeutic radiation 3a are repeated. The treatment by the follow-up irradiation to the irradiation field 5 from the position of the half spherical shell of the bed is performed.
[0064]
Next, a treatment procedure using the pseudo non-isocentric radiotherapy apparatus of the present invention will be described with reference to FIGS. 15 and 16.
[0065]
In radiation therapy, a doctor makes a treatment plan. The treatment plan is based on various examinations performed before surgery, and doctors can use the apparatus of the present invention during surgery to perform image diagnosis of the affected lesion directly and in real time with high accuracy. Highly reliable radiation therapy can be performed.
[0066]
As shown in FIG. 16A, a diagnostic image of the irradiation field 5 and its vicinity region is constructed using only the X-ray CT apparatus 30. Each sectional view of the treatment field 5 is confirmed on the system screen, and an outline for image tracking is defined. Prior to the start of treatment, the mapping of the irradiation field 5 has been completed, and the contour of the irradiation field 5 is defined by a plurality of slices with reference to this.
[0067]
As shown in FIG. 16B, the image tracking system of the radiotherapy apparatus extracts the contour of the image of the actual irradiation field 5, performs pattern matching with the defined contour line, and starts image tracking. . The doctor visually confirms the image tracking status.
[0068]
As shown in FIG. 16C, after the image tracking is stabilized, the doctor operates the master arm switch (Master Arm SW) to set the system to the ARMED state. The system displays the aim on the image with a crosshairline and the irradiation volume in red. Since image tracking continues, the aiming and irradiation volume automatically follow as the irradiation field moves.
[0069]
As shown in FIG. 16 (d), the irradiation of the therapeutic radiation 3a is started by the trigger operation of the doctor. The scheduled irradiation time is determined at the stage of the treatment plan, the countdown starts on the screen, and the therapeutic radiation automatically stops when the count reaches zero (time t4). The dose distribution is continuously displayed on the screen, and the doctor keeps pulling the trigger while confirming this, and continues the irradiation. The system continues to alternately sample images and irradiate therapeutic radiation at high speed, and continue image tracking and therapeutic radiation in real time. Even before the countdown reaches zero, if the doctor releases the trigger, the therapeutic radiation is immediately stopped at that timing, so safety is sufficiently ensured.
[0070]
As shown in FIG. 16E, the doctor sets the system in a safe state by setting the master arm switch (Master Arm SW) to the SAFE position, and moves the irradiation head 10 to the next irradiation position. After the end of irradiation at each portal and after the end of the series of irradiations, the doctor checks the total dose, which is the total cumulative dose. The accumulated dose and the accumulated dose distribution within one course are displayed on the screen and stored in a treatment file created for each patient.
[0071]
According to the treatment apparatus of this embodiment, the irradiation head can be swung at a high speed within 0.1 seconds including the image processing time, and can follow the movement of the irradiation field (affected area). Can be irradiated with radiation. In this way, it is possible to perform non-isocentric irradiation with high response and high accuracy corresponding to the movement of the affected part, so that the movement of organs such as breathing and heartbeat, peristalsis and urine volume in the bladder etc. A site where an irradiation target such as a tumor moves under the influence of the state can be set as a treatment target.
[0072]
According to the present embodiment, in addition to the isocentric movement of the entire irradiation head unit, the irradiation head unit itself swings one or two axes around an appropriate rotation center such as the center of inertia. As a result, it becomes possible to perform pseudo-non-isocentric irradiation treatment, and the effect is completely comparable to that of a completely non-isocentric irradiation treatment apparatus. Further, the required swing angle is about 3 ° (± 1.5 °), and it can follow the movement of the irradiation field by breathing or heartbeat at high speed.
[0073]
According to the present embodiment, unlike a cantilever type robot arm that is problematic in terms of rigidity, it is possible to adopt an irradiation head support structure with high strength and high rigidity, and mechanically guarantee high absolute accuracy. Is possible. This eliminates the need for teaching that is required when using a robot arm to ensure the required positioning accuracy.
Efficient treatment is possible.
[0074]
It is problematic in terms of patient safety to apply a general-purpose industrial robot arm having an excessive degree of freedom far exceeding that required for non-isocentric irradiation treatment. In other words, in the event of an accident such as a malfunction of the robot arm, the robot arm or the 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, in the present embodiment, the movable range of the irradiation head support mechanism and the irradiation head itself is mechanically limited, and absolute safety for the patient can be ensured.
[0075]
In the prior art, the irradiation field could not be monitored in real time during irradiation treatment, and irradiation based on estimation was forced. However, according to the present invention, a normal X-ray fluoroscope, X-ray CT apparatus, PET With an image acquisition device such as DSA, the irradiation field can be monitored in real time during irradiation treatment, and irradiation treatment with high reliability and safety is possible.
[0076]
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 becomes possible.
[0077]
The man-machine interface with the doctor shown in the embodiment of the present invention enables reliable radiotherapy with excellent safety and reliability.
[0078]
(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. In addition, description of the part which this embodiment overlaps with said embodiment is abbreviate | omitted.
[0079]
In the apparatus 6A of the present embodiment, a treatment irradiation head 10, an image acquisition X-ray source (CT X-ray tube) 97, and a sensor array 98 are mounted on a rotating drum (treatment gantry) 99. That is, the overall structure of the apparatus is the rotary X-ray CT apparatus of the first embodiment. Set 3 The irradiation head 10 is provided on the zero drum portion. The rotation center of the rotary drum (treatment gantry) 99 is the isocenter 5a. The irradiation head 10 is composed of an electronic linac of 4 MeV to 10 MeV, and can swing around two axes (S1 and S2) as shown in the figure. By these swinging operations, non-isocentric irradiation around the drum rotation axis is possible. is there. The swing of the S2 axis needs to include aiming angle correction accompanying the rotation of the drum. On the other hand, the aiming angle correction for the swing of the S1 axis is not necessary.
[0080]
The image acquisition X-ray source 97 and the sensor array 98 are respectively mounted at locations where the irradiation head 10 does not interfere with each other, and the image acquisition X-ray source 97 and the sensor array 98 face each other. The X-ray sensor array 98 for detection is a multi-row type multi-row sensor. The X-ray CT apparatus and PET require real-time imaging, and high-speed real-time image reconstruction calculation processing is required.
[0081]
(Third embodiment)
Next, a third embodiment of the present invention will be described with reference to FIG. In addition, description of the part which this embodiment overlaps with said embodiment is abbreviate | omitted.
[0082]
In the apparatus 6B of the present embodiment, a set of two sets of X-ray sources 97A and 97B and sensor arrays 98A and 98B constituting an irradiation head 10, a normal X-ray fluoroscopic apparatus, is provided on a rotating drum (treatment gantry) 99. Has been. That is, unlike the second embodiment, the rotary drum 99 is not equipped with an X-ray source and a sensor array for an X-ray CT apparatus, but constitutes a normal X-ray fluoroscopic apparatus in this embodiment. Two sets of X-ray sources 97A and 97B and sensor arrays 98A and 98B are provided so that the lines of sight of the set of X-ray fluoroscopes do not coincide with each other. Thereby, X-ray fluoroscopic images of markers such as landmarks or minute gold plates in the body of the patient 4 are acquired in two axial directions, and the movement of the affected area is grasped. As an image enhancement method for a fluoroscopic image, a method of performing image processing such as DSA using a contrast agent is also conceivable.
[0083]
The irradiation head 10 is composed of an electronic linac of 4 MeV to 10 MeV, and can swing around two axes (S1 and S2) as shown in the figure. By these swinging operations, non-isocentric irradiation around the drum rotation axis is possible. is there. The swing of the S2 axis needs to include aiming angle correction accompanying the rotation of the drum. On the other hand, the aiming angle correction for the swing of the S1 axis is not necessary.
[0084]
(Fourth embodiment)
Next, a radiation therapy apparatus according to the fourth embodiment of the present invention will be described with reference to FIGS.
[0085]
As shown in FIG. 20, the radiotherapy apparatus according to the present embodiment includes elements arranged on the treatment room 200 side and elements arranged in an operation room 202 isolated from the treatment room 200 by a partition wall 201.
[0086]
Elements disposed in the treatment room 200 include a support moving mechanism 210, an irradiation head 220 supported and moved on a first spherical coordinate set in advance by the support moving mechanism 210, a microwave oscillator 230, and an irradiation head 220. The fixed waveguide section 240, the moving waveguide section 250, and the in-head waveguide section 260, which are microwave transmission systems that transmit the microwave power generated by the microwave oscillator 230 to the therapeutic radiation generation section 221 of the inside. And the bed part 270.
[0087]
The element arranged in the operation room 202 is a system control console 280.
[0088]
The support moving mechanism 210 supports and moves a pair of bases 211 and 212 fixed to the floor of the treatment room 200, a pair of tilting mechanisms 213 and 214 provided on the bases 211 and 212, and the irradiation head 220. A guide rail 215 formed with a semicircular arc-shaped track and a pair of weights 216 and 217. That is, the track 215A is formed in the middle portion of the guide rail 215, and both ends 215B1, 215B2 thereof are supported by tilt mechanisms 213, 214 provided on the bases 211, 212. By driving the tilting mechanisms 213 and 214, the guide rail 215 is rotationally driven in the direction indicated by reference numeral 301 around the isocenter 300.
[0089]
The irradiation head 220 includes a therapeutic radiation generation unit 221 including an electron gun, an accelerator, a target, a collimator, a vacuum pump, and the like, and a mechanism such as a rack and pinion, a belt, and a pulley. 302 has a revolving mechanism 222 that revolves in the direction indicated by 302, and a gimbal mechanism 223 that swings the therapeutic radiation generator 221 in two orthogonal directions indicated by reference numeral 303. Here, the operation of the tilting mechanisms 213 and 214 and the circular movement mechanism 222 can cause the irradiation head 220 to rotate the isocenter 300 in an isocentric manner. Further, the operation of the gimbal mechanism 223, which will be described later, can cause the irradiation head 220 to rotate in a pseudo non-isocentric manner.
[0090]
The microwave oscillator 230 includes a microwave electron tube such as a klystron. The microwave oscillator 230, the microwave transmission system, and the therapeutic radiation generator 221 are integrated and incorporated in a gantry including an irradiation head that is a rotating body in a conventional radiotherapy apparatus such as a small electronic linac. However, in the radiotherapy apparatus of this embodiment, a light irradiation head is realized by installing the microwave oscillator 230, which is a heavy object, on the floor of the treatment room 200. By combining the light-weighted irradiation head 220 with the characteristic support movement mechanism 210, the irradiation head 220 can be placed at an arbitrary position on the spherical coordinate system defined in the space of the treatment room 200. It is possible to move to.
[0091]
The moving waveguide section 250 is a pantograph mechanism including first and second linear waveguides 251 and 252 and first, second and third rotary RF couplers 253, 254 and 255, and is a fixed waveguide. The portion 240 and the in-head waveguide portion 260 are connected. That is, among the first, second, and third rotary RF couplers 253, 254, and 255 of the same type, the second rotary RF coupler 254 is representatively shown including the first and second linear waveguides 251 and 252. This will be described with reference to FIG.
[0092]
In FIG. 21, the second rotary RF coupler 254 has a first cylindrical body 254A to which the first linear waveguide 251 is connected on one end side, and the first cylindrical body having the same axis as the first cylindrical body 254A. 254A includes a second cylindrical body 254B, one end of which is rotatably combined via a bearing 254C and the other end of which is connected to the second straight waveguide 252. The axial direction of the first and second cylindrical bodies 254A and 254B is perpendicular to the extending direction of the first and second linear waveguides 251 and 252.
[0093]
In addition, a band-pass filter plate 254D formed with two openings is provided in the openings of the first and second cylinders 254A and 254B. Further, a magnetic seal mechanism 254E is provided between the first cylinder 254A and the second cylinder 254B. The magnetic seal mechanism 254E replaces the O-ring for hermetic sealing, and has a structure in which the magnetic fluid 254E3 is sandwiched between a pair of electromagnets 254E1 and 254E2. By providing such a magnetic seal mechanism 254E between the first cylindrical body 254A and the second cylindrical body 254B, maintenance management can be performed as compared with an O-ring that requires periodic replacement due to deterioration as in the prior art. This is advantageous.
[0094]
According to the second rotary RF coupler 254 and the first and second linear waveguides 251 and 252 as described above, the microwave power transmitted from the extending direction of the first linear waveguide 251 is the second rotary RF. The light is bent at a right angle at the inlet of the coupler 254 and is bent again at a right angle at the outlet and transmitted in the extending direction of the second straight waveguide 252. Further, since the first cylindrical body 254A and the second cylindrical body 254B of the second rotary RF coupler 254 are rotatable relative to each other, the first linear waveguide connected to the first and second cylindrical bodies 254A and 254B at a right angle. 251 and the second straight waveguide 252 can be rotated in different directions.
[0095]
Accordingly, the moving waveguide section 250 has a structure similar to that of the second rotary RF coupler 254, with the other end of the first linear waveguide 251 having one end connected to the second rotary RF coupler 254 as a guide. The other end of the second linear waveguide 252 connected to the first rotary coupler 253 fixed to the end of the rail 215 and connected to the second rotary RF coupler 254 is connected to the second rotary RF coupler 254. Are connected to the third rotary RF coupler 255 fixed to the irradiation head 220, and the first, second, and third rotary RF couplers 253 and 254 are moved with the movement of the irradiation head 220. , 255 can rotate to open and close the first and second linear waveguides 251 and 252 with the second rotary RF coupler 254 as the center. This is because the movable waveguide section 250 including the first and second linear waveguides 251 and 252 and the first, second and third rotary RF couplers 253, 254 and 255 is a pantograph mechanism. Is shown.
[0096]
FIG. 22 shows an example in which a curved transmission path is formed using two rotary RF couplers 254 and 254 ′ and five waveguides. In this example, a rotary RF coupler 254 and linear waveguides 256 and 257 similar to those in FIG. 21 and a rotary RF coupler 254 ′ and linear waveguides 256 ′ and 257 ′ similar to those shown in FIG. It is the structure connected by H.258.
[0097]
In this manner, a plurality of sets of the rotary RF coupler 254 and the plurality of waveguides shown in FIG. 21 are manufactured, and these are connected by the bend type waveguides, whereby a bent transmission path can be easily formed. .
[0098]
Next, the relationship between the irradiation head 220 and the moving waveguide section 250 will be described with reference to FIG. That is, when the isocenter 300 is defined in FIG. 20, the irradiation head 220 can be moved to an arbitrary position on the spherical coordinate system defined in the space of the treatment room 200 by the support moving mechanism 210. This spherical coordinate system can be represented by P1 (r1, θ1, φ1) in FIG. In this case, r1 is a distance between the isocenter 300 and the target. Further, the third rotary RF coupler 255 of the moving waveguide section 250 moves in response to the coordinate system P2 (r2, θ2, φ2) when the irradiation head 220 moves in the spherical coordinate system P1 (r1, θ1, φ1). ) On the spherical coordinate system. r2 is a distance between the isocenter 300 and the axis of the third rotary RF coupler 255.
[0099]
As described above, according to the radiotherapy apparatus of this embodiment, the moving waveguide unit 250 can be moved on the spherical coordinate system P2 in accordance with the spherical coordinate system P1 in which the irradiation head 220 moves, and the moving waveguide unit 250 can be moved. Can be made to follow the movement of the irradiation head 220.
[0100]
Next, the fixed waveguide section 240 will be described. That is, the fixed waveguide section 240 is a waveguide similar to the linear waveguide used in the moving waveguide section 250, and an E bent waveguide having flanges 241 and 242 provided at both ends shown in FIG. A pipe 243, an H bent waveguide 245 provided with flanges 244, 245 at both ends shown in FIG. 25, and a rotary coupler similar to the rotary RF couplers 253, 254, 255 used in the moving waveguide section 250; The microwave oscillator 230 and the moving waveguide unit 250 are connected. In FIG. 20, the fixed waveguide section 240 is connected from the output end of the microwave oscillator 230 to the first rotary RF coupler 253 provided at the end 215B2 of the guide rail 215 through the base 212.
[0101]
Next, with reference to FIGS. 26A and 26B, the irradiation head 220 and the in-head waveguide section 260 will be described. As described with reference to FIG. 20, the irradiation head 220 includes a therapeutic radiation generation unit 221, a circling movement mechanism 222, and a gimbal mechanism 223, and an in-head waveguide unit 260 is additionally provided. In FIGS. 26A and 26B, the circular movement mechanism 222 does not appear in the drawing. Servo mechanisms 223B and 223C for swinging in two directions perpendicular to the frame 223A of the gimbal mechanism 223 are provided, and the entire frame 223A is swung at the position positioned by the circular movement mechanism. On the frame 223A, an electron gun 221A, an accelerator 221B such as a C-band standing wave linear accelerator, a target 221C, a collimator 221D, and a vacuum pump 221E connected to the accelerator 221B are mounted.
[0102]
Such a therapeutic radiation generator 221 accelerates the electron beam emitted from the electron gun 221A from the accelerator 221B, causes the accelerated electron beam to collide with the target 221C, and generates radiation. The patient is molded with 221D and irradiated with therapeutic radiation from the irradiation head 220 to a patient (not shown). Also.
[0103]
In the above, the in-head waveguide section 260 is connected to the accelerator 221B. This in-head waveguide section 260 has a rotary RF coupler 261 having an RF window 262 inside and one end connected to the accelerator 221B. A bend waveguide 263 is connected to the other end of the rotary RF coupler 261. A rotary RF coupler 261 and a bend-shaped waveguide 263 having an RF window 262 inside are mounted on a frame 223A of the gimbal mechanism 223.
[0104]
Here, the space by the waveguide section 262A from the RF window 262 to the accelerator 221B, the electron gun 221A, the accelerator 221B, and the target 221 is evacuated by the vacuum pump 221E. Further, the inside of the in-head waveguide section 260, the fixed waveguide section 240, and the movable waveguide section 250 from the RF window 262 to the microwave oscillator 230 are electrically insulating gas such as SF6 gas is 0.1 to 0.1%. It is filled at a pressure of 0.2 MPaG.
[0105]
Further, waveguides 265, 266, 267 are provided on the side of the circular movement mechanism, and the waveguide 267 is connected to the third rotary RF coupler 255 of the movement waveguide unit 250. Here, the bend type waveguide 263 mounted on the frame 223A of the gimbal mechanism 223 and the waveguide 265 provided on the side of the revolving mechanism are flexible waveguides having flanges 264A and 264B shown in detail in FIG. They are connected by a tube 264. 24, 25, and 27, the flange 268 shown in FIG. 28 can be used. In addition, in the in-head waveguide section 260, when a bent transmission path is formed, an E-bent waveguide 243 provided with flanges 241 and 242 at both ends shown in FIG. 24, and both ends shown in FIG. An H-bent waveguide 245 provided with flanges 244 and 245 can be used.
[0106]
A bed portion 270 shown in FIG. 20 includes a top plate 271 that moves in at least one of the Z direction (vertical direction) and the X and Y directions (horizontal direction) while placing the patient 272 thereon. The top plate 271 is moved by a moving mechanism (not shown) provided in the bed part 270.
[0107]
A system control console 280 shown in FIG. 20 is configured to automatically or manually operate the tilting mechanisms 213 and 214, the therapeutic radiation generation unit 221 of the irradiation head 220, the orbital movement mechanism 222, the gimbal mechanism 223, the microwave oscillator 230, and the bed unit 270. More control.
[0108]
According to the radiation therapy apparatus of the present embodiment configured as described above, the following effects are obtained. That is, the microwave oscillator 230, which is a heavy object, is installed on the floor of the treatment room 200 to realize the lightened irradiation head 220, and in combination with the characteristic support moving mechanism 210, the irradiation head 220 is changed into the treatment room. It is possible to move to an arbitrary position on the spherical coordinate system P1 defined in the 200 space.
[0109]
Further, according to the radiotherapy apparatus of the present embodiment, the moving waveguide unit 250 can be moved on the spherical coordinate system P2 in accordance with the spherical coordinate system P1 to which the irradiation head 220 moves. The movement can follow the movement of the irradiation head 220, and the microwave power can be easily supplied to the irradiation head 220 at an arbitrary position.
[0110]
Further, the moving waveguide section 250 constitutes a pantograph mechanism by the first and second linear waveguides 251 and 252 and the first, second and third rotary RF couplers 253, 254 and 255. Therefore, the first linear waveguide 251 and the second linear waveguide 252 can be easily opened and closed with the second rotary RF coupler 254 as the center, and the amount of movement can be absorbed, and interference with the patient 272 can be prevented. It can be prevented beforehand.
[0111]
The fixed waveguide section 240 and the in-head waveguide section 260 are similar to the E bent waveguide 243, the H bent waveguide 245, and the rotary RF couplers 253, 254, and 255 together with the straight waveguide. Therefore, a bent transmission path can be formed with the shortest distance, which contributes to downsizing.
[0112]
Further, by providing a magnetic seal mechanism 254E between the first cylinder 254A and the second cylinder 254B of the rotary RF coupler 254, the occurrence of leakage due to wear is suppressed compared to the conventional O-ring. And replacement cycles associated with degradation can be extended.
[0113]
Further, the bend-type waveguide 263 mounted on the gimbal mechanism 223 in the in-head waveguide section 260 and the waveguide 265 provided on the circumferential movement mechanism side are connected by a flexible waveguide 264. Therefore, even if the therapeutic radiation generating unit 221 including the bend-shaped waveguide 263 is displaced by a slight angle by the swinging operation by the gimbal mechanism 223, the positional deviation of the therapeutic radiation generating unit 221 accompanying the swinging operation is easy. Absorption by the flexible waveguide 264 is possible. As a result, the irradiation head 220 can be smoothly rotated in a pseudo non-isocentric manner by the gimbal mechanism 223 while supplying predetermined microwave power to the therapeutic radiation generator 221.
[0114]
Furthermore, in the radiotherapy apparatus according to the present embodiment, in the microwave transmission system between the microwave oscillator 230 and the accelerator 221B, the RF window 262 is provided in the vicinity of the accelerator 221B, which is a part that uses microwaves. The only part that needs to be evacuated is the narrow space in the vicinity of the accelerator 221B formed by the waveguide section 262A from the RF window 262 to the accelerator 221B, the electron gun 221A, the accelerator 221B, and the target 221. The vacuum pump 221E can be used with a small capacity, which greatly contributes to the reduction in size and weight of the irradiation head 220. In addition, since the portion that needs to be evacuated is a narrow space near the accelerator 221B, reaching a high degree of vacuum is achieved and the risk of discharge is reduced. Furthermore, since the portion that needs to be evacuated is a narrow space near the accelerator 221B, the frequency of occurrence of vacuum leakage can be reduced.
[0115]
The microwave transmission system from the RF window 262 to the microwave oscillator 230, that is, the inside of the in-head waveguide section 260, the fixed waveguide section 240, and the movable waveguide section 250 has an electrically insulating gas such as SF6 gas. However, since it is filled at a pressure of 0.1 to 0.2 MPaG, the maintenance capability of the microwave transmission system is improved by the internal pressure in the microwave transmission system.
[0116]
【The invention's effect】
As described above, according to the present invention, Even if the therapeutic radiation generator including the waveguide, which includes the waveguide, and the electron gun, the linear accelerator, and the target is displaced by a slight angle by the swinging operation, the positional deviation of the therapeutic radiation generating unit accompanying the swinging motion is not caused by the gimbal mechanism. It can be easily absorbed by the flexible waveguide, which makes it possible to smoothly rotate the irradiation head by the gimbal mechanism while supplying a predetermined microwave power to the therapeutic radiation generator, It is possible to provide a radiotherapy apparatus having excellent therapeutic performance.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a radiotherapy apparatus according to a first embodiment of the present invention viewed from a direction orthogonal to a bed axis.
FIG. 2 is a configuration diagram of the radiotherapy apparatus of the embodiment viewed from the bed axis direction.
FIG. 3 is a perspective view for explaining radiotherapy by the radiotherapy apparatus of the embodiment.
4A and 4B show an irradiation head in a radiotherapy apparatus according to a second embodiment of the present invention, in which FIG. 4A is a partial cross-sectional view seen from the front, and FIG. 4B is a cross-sectional view taken along IVB-IVB in FIG. (C) is sectional drawing which follows IVC-IVC in (a).
FIG. 5 is a configuration diagram showing an ultra-compact C-Band accelerator provided in an irradiation head in the radiation therapy apparatus according to the embodiment.
FIG. 6 is a perspective view showing an irradiation head and a patient when performing radiation therapy in a pseudo non-isocentric manner by the radiation therapy apparatus of the embodiment.
7 is a partial cross-sectional view taken along the line VII-VII in FIG. 6 for explaining an example of the swinging operation of the irradiation head when performing radiation treatment in a pseudo non-isocentric manner by the radiation treatment apparatus of the embodiment; Figure.
FIG. 8 is a diagram for explaining another example of the swinging operation of the irradiation head when performing radiation treatment in a pseudo non-isocentric manner by the radiation therapy apparatus of the embodiment, and is a portion along VIII-VIII in FIG. Sectional drawing.
FIG. 9 is a block diagram of the radiation therapy apparatus according to the embodiment.
FIG. 10 is a perspective view showing an irradiation head of the radiotherapy apparatus according to the embodiment.
11A and 11B show a swing mechanism in the embodiment, FIG. 11A is a perspective view showing a waveguide, a swing mechanism, and a drive motor, and FIG. 11B is a cross section taken along XIB-XIB in FIG. The figure, (c) is sectional drawing which follows XIC-XIC in (a), (d) is sectional drawing which follows XID-XID in (a).
FIG. 12 is a perspective view showing a waveguide system and a rotary RF coupler in the radiation therapy apparatus of the embodiment.
FIG. 13 is a perspective view showing a rotary RF coupler and a waveguide in the radiation therapy apparatus according to the embodiment.
FIG. 14 is a view for explaining a rotary RF coupler in the radiation therapy apparatus according to the embodiment;
FIG. 15 is a timing chart showing an operation in the embodiment;
FIG. 16 is a view showing the operation procedure of radiotherapy in the embodiment by a change of the monitor screen.
FIG. 17 is a configuration diagram of a radiotherapy apparatus according to a second embodiment of the present invention viewed from the direction of the bed axis.
FIG. 18 is a configuration diagram of the radiotherapy apparatus according to the embodiment viewed from the direction of the bed axis.
FIG. 19 is a configuration diagram of a radiation therapy apparatus according to a third embodiment of the present invention viewed from the direction of a bed axis.
FIG. 20 is a perspective view showing a radiation therapy apparatus according to the fourth embodiment of the present invention.
FIG. 21 is a sectional view of a rotary RF coupler according to the embodiment.
FIG. 22 is a diagram showing a transmission system in which a rotary RF coupler and a waveguide are combined in the embodiment.
FIG. 23 is a view showing a relationship between a spherical coordinate system related to the irradiation head and a spherical coordinate system related to the moving waveguide unit in the same embodiment;
FIG. 24 is a view showing an E-bend waveguide in the same embodiment;
FIG. 25 is a view showing an H-bend waveguide in the same embodiment.
FIG. 26 shows an irradiation head in the same embodiment, where (a) is a front view and (b) is a side view.
FIG. 27 is a view showing a flexible waveguide in the same embodiment;
FIG. 28 is a view showing a flange in the same embodiment;
[Explanation of symbols]
200 ... treatment room
201 ... partition wall
202 ... operation room
210 ... Supporting movement mechanism
211, 212 ... Base
213, 214 ... Tilt mechanism
215 ... Guide rail
215A ... orbit
216, 217 ... Weight
220 ... Irradiation head
221 ... Radiation generator for treatment
222. Circulating movement mechanism
223 ... Gimbal mechanism
230 ... Microwave oscillator
240 ... fixed waveguide section
250 ... Moving waveguide part
260: In-head waveguide section
270 ... Sleeper
280 ... System control console

Claims (12)

An irradiation head having a gimbal mechanism for swinging the therapeutic radiation generating unit and a therapeutic radiation generating unit including an electron gun, a linear accelerator, and a target;
A support moving mechanism for supporting and moving the irradiation head on a predetermined spherical coordinate;
A microwave oscillator disposed at a stationary position for generating a microwave to be supplied to the irradiation head;
One end portion electromagnetically connected to the microwave oscillator, in a radiation therapy apparatus comprising a waveguide portion to which the other end portion is electromagnetically connected to the linear accelerator,
A radiotherapy characterized in that a waveguide of the waveguide section mounted on the gimbal mechanism and a waveguide of the waveguide section from the microwave oscillator are connected by a flexible waveguide. Equipment . Vacuum and internal waveguide portion to the linear accelerator from RF window provided, and a vessel for interior and said and said electron gun and said linear accelerator target to the waveguide section you located in the irradiation head The radiotherapy apparatus according to claim 1, further comprising a vacuum pump for exhausting.   The radiotherapy apparatus according to claim 2, wherein the vacuum pump is disposed in the irradiation head. Claims 1 to 3 or of the radiotherapy apparatus electrically insulating gas into the waveguide section to the microwave oscillator from the RF window provided in the waveguide section you located in the irradiation head is filled.   The radiotherapy apparatus according to any one of claims 1 to 4, wherein the waveguide unit includes means for moving in a second spherical coordinate according to the first spherical coordinate.   The radiotherapy apparatus according to claim 1, wherein the waveguide section includes a waveguide and a rotary RF coupler. Wherein at least one of the guide Namikan section, one of the radiation therapy apparatus according to claim 1 or 6 including the bend waveguide. Wherein at least one of the guide Namikan section, one of the radiation therapy apparatus according to claim 1 to 7 including a flexible waveguide.   The rotary RF coupler has a first cylinder having a waveguide connected to one end thereof, and a shaft having the same axis as the first cylinder, and the other end of the first cylinder is rotatably combined at one end. And a second cylinder having another waveguide connected to the other end.   The radiotherapy apparatus according to claim 6, wherein the rotary RF coupler includes a magnetic seal that seals at least one of an internal vacuum and the electrically insulating gas. An isocentric rotation mechanism for rotating the irradiation head around an isocenter;
The radiotherapy apparatus according to claim 1, further comprising a pseudo non-isocentric rotation mechanism that swings the irradiation head at a position where the irradiation head is rotated by a predetermined angle by the isocentric rotation mechanism.   The radiotherapy apparatus according to claim 11, wherein the irradiation head includes a gimbal mechanism that swings at least in two orthogonal directions.

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