JP5501058B2 - Radiation dose measuring device operating three-dimensionally in the phantom over a wide range - Google Patents

Description

  The present invention relates to a radiation dose measuring device for radiation irradiated from a radiotherapy treatment device, and more particularly to a radiation dose measuring device operating three-dimensionally over a wide range in a phantom.

  Conventionally, radiation therapy is known in which a tumor formed inside a human body is treated by irradiating predetermined radiation from the outside. In this radiotherapy, it is desirable not to irradiate normal parts other than the tumor, and various radiotherapy apparatuses that can irradiate the tumor with high accuracy have been proposed.

  By the way, when a tumor is formed at a position where an organ such as the lung moves, the position of the tumor moves along with the movement of the lung or the like, so that there is a problem that the radiation irradiated from the radiotherapy apparatus deviates from the tumor. It was. Therefore, a radiotherapy apparatus that can automatically change the amount of radiation emitted in accordance with the movement of the tumor is also known. In this radiotherapy, before performing treatment with the radiotherapy device, after analyzing the movement of the tumor accompanying respiration in advance, create a control program that irradiates radiation only when the tumor exists in the radiation irradiation field, The control program controlled the radiation therapy device to follow the movement of the tumor and performed treatment.

  However, if it is not known whether the position and timing of radiation irradiation by the radiotherapy device really follow the actual movement of the tumor, and if it does not follow, the radiation dose sufficient for the tumor There is a possibility that treatment results may be deteriorated due to the inability to irradiate, or that a problem may occur due to radiation being applied to a normal site.

  Therefore, an apparatus including a cam formed in a predetermined shape, a shaft body that advances and retreats by rotation of the cam, and a film storage box attached to the tip of the shaft body has been proposed (for example, Patent Document 1). In this apparatus, the shape of the cam is made to correspond to the movement of the moving organ, so that the film storage box attached to the tip moves like the organ, and the radiotherapy apparatus is applied to the film storage box. It is possible to confirm whether or not the position and timing of the irradiated radiation correctly follows the organ.

  On the other hand, when confirming the position and radiation dose of radiation irradiated from a radiotherapy device, since the tumor to be irradiated is generally present inside the human body, the radiation irradiated from the outside of the human body is There is a problem that the radiation is refracted or the dose is reduced by being disturbed or absorbed by the human tissue between the tumor. Therefore, after creating a simulated human body (hereinafter referred to as a phantom) using a material that is substantially equivalent to the human body with respect to radiation, a detection unit that measures the radiation dose at a position corresponding to the tumor in the phantom (for example, radiation By using this phantom, the position and dose of radiation emitted from the radiation therapy device can be verified to improve the treatment results for radiation therapy. Yes.

  However, the detection unit is attached at a position corresponding to the tumor in the phantom, and the phantom itself does not move. Therefore, when the position where the tumor (detection unit) is located is moved by breathing or the like, the detection unit is a human body. Therefore, there is a problem that the radiotherapy by the radiotherapy apparatus cannot be sufficiently verified.

  On the other hand, by combining the phantom and the device of Patent Document 1, the tip (film storage box) of the device of Patent Document 1 is inserted into the phantom so that the film storage box moves inside the phantom. It is possible. However, in the device of Patent Document 1, the film storage box is moved by the advancement and retraction of the shaft body by the rotation of the cam, and the movement of the film storage box (corresponding to an organ or tumor) is only in one direction. For example, when targeting a tumor formed in the lung, the film storage box must be moved up and down, so the device body that moves the film storage box must be placed above the phantom. In addition, there is a possibility that the apparatus main body becomes in the way and cannot be irradiated with radiation.

  Further, when the conventional phantom and the device of Patent Document 1 are combined, when replacing the film in the film storage box disposed in the phantom, the phantom and the device of Patent Document 1 must be separated. By separating, the positional relationship between the phantom and the device disclosed in Patent Document 1, the positional relationship between the phantom and the radiation therapy device, and the like are shifted, and the phantom and the device disclosed in Patent Document 1 are aligned each time the film is replaced. There is a problem that takes time.

  Furthermore, in the apparatus of Patent Document 1, since the film storage box is moved by rotating the cam, a cam having a shape corresponding to the target organ or patient must be created. However, there are problems that it takes time and cost. Further, in the apparatus of Patent Document 1, as described above, the film storage box can be moved only in one direction, and there is a problem that the movement of the actual organ cannot be faithfully reproduced due to the structure. Even if tracking is confirmed by the device, the position and timing of the radiation irradiated by the radiotherapy device may be different from the actual movement of the organ (tumor), and the position where the radiation should be irradiated is shifted and sufficient There is a possibility that treatment results cannot be obtained.

  In addition, in a radiotherapy device, it is necessary to periodically check whether or not the position of the radiation to be irradiated is accurately applied to the target position and perform maintenance. For simple movements in only one direction The apparatus of Patent Document 1 can also be verified. However, when the target moves in a three-dimensionally complex manner, there is no measurement device for verifying the movement, and the radiotherapy apparatus cannot be sufficiently maintained.

  On the other hand, even in the case of a radiographic imaging apparatus such as CT (Computed Tomography), it is necessary to periodically verify whether or not the actual internal tissue (cross section) matches the photographed cross section to calibrate the apparatus. However, the conventional apparatus such as Patent Document 1 cannot be sufficiently verified.

  Therefore, in view of the above situation, the present invention can accurately reproduce a movement closer to the movement of the human body, can easily replace the detection unit, and can perform a three-dimensional operation over a wide range in the phantom. The issue is to provide

In order to solve the above-mentioned problems, a radiation dose measuring device operating three-dimensionally in a wide range within the phantom of the present invention is “mounted on the bed of a radiation therapy device or a radiographic image device and imitating a human body. A frame-shaped device main body arranged on the rear side of the phantom having a space, a first rail supported in the device main body and extending in the left-right direction, and held by the first rail so as to be movable in the left-right direction The first base, a first drive mechanism for moving the first base in the left-right direction, and the first base that is driven to move in the left-right direction by the first drive mechanism. A second rail extending in the vertical direction, a second base held by the second rail so as to be movable in the vertical direction, a second drive mechanism for moving the second base in the vertical direction, and the second drive Top by mechanism A third rail supported by the second base driven to move in the direction and extending in the front-rear direction in the apparatus body; a third base held movably in the front-rear direction by the third rail; A third drive mechanism for moving the three bases in the front-rear direction, and a rear end supported by the third base driven to move in the front-rear direction by the third drive mechanism, and the third base moving forward A front end is projectable from the apparatus main body into the front phantom, and a guide member formed in a cylindrical shape by a synthetic resin, and an outer periphery of the guide member is supported so as to be slidable in the front-rear direction, and the front end of the third rail The slide holding member attached to the second base on the side, and the guide member supported by the slide holding member and the third base are inserted and supported so as to be detachable from the rear side. A support rod which is formed into a rod shape by fat comprises a detection unit for measuring the projecting from the guide member to the front, the radiation dose with attached to the front end of the supporting rod "be characterized.

  Here, “horizontal direction”, “vertical direction”, and “front / rear direction” mean the width direction of the bed with respect to the bed attached to the radiotherapy apparatus, the longitudinal direction of the bed with the longitudinal direction, and the bed surface. The direction perpendicular to the vertical direction is the vertical direction.

  In addition, the “apparatus body” includes “the outer shape is formed in a rectangular parallelepiped shape”, “the outer shape is formed in a flat plate shape”, “the outer shape is formed in a triangular shape in a side view”, and the like. Can be mentioned. In addition, as “first rail”, “second rail”, and “third rail”, “single rails that can be moved in a direction other than the moving direction” or “a plurality of rails” are used. Thus, it is possible to make the state incapable of moving in directions other than the moving direction ".

  The “first drive mechanism”, “second drive mechanism”, and “third drive mechanism” are “a rod-like screw member extending along the rail, screwed with the screw member, and movable by the rail. “A nut portion attached to a held base and a motor that rotationally drives a screw member”, “a rack gear extending along a rail, a pinion gear meshing with the rack gear, and a pinion gear. And a motor mounted on a base movably held by a rail, "a sprocket that is rotatably arranged at both ends of the rail, and a part that is wound around the sprocket and that can be moved by the rail And the like having a chain fixed to a held base and a motor for rotating one of the sprockets. Each drive mechanism is controlled by a computer based on a predetermined control program.

  Furthermore, the “synthetic resin” forming the guide member and the support rod includes “acrylic resin”, “polycarbonate resin”, “ABS resin”, “polypropylene”, “polyarylate resin”, “methacrylic resin”, “PEEK ( Polyether, ether, ketone) ”,“ polyamide resin ”, and the like.

  In addition, the “slide holding member” includes “a bush-shaped member (sliding bush, metal bearing, etc.) that contacts the outer peripheral surface of the cylindrical guide member over the entire circumference”, “cylindrical guide. And those having a plurality of balls or rollers that roll on the outer peripheral surface of the member (ball bearings, roller bearings, etc.).

  In addition, as the “detection unit”, “thing provided with a detection film (film badge) sensitive to radiation”, “Geiger-Muller counter (GM counter)”, “NaI (Tl) scintillation detector”, “ Semiconductor detectors, “thermofluorescence dosimeters (TLDs)”, “fluorescent glass dosimeters”, “ionization chambers”, and the like. In addition, when radiation detection sensors, such as a GM counter, a scintillation detector, and a semiconductor detector, are used, radiation can be detected in real time.

  By the way, the guide member inserted into the phantom has a detection unit attached to the front end, so that the rear end side is supported in a so-called cantilevered state, and the weight of the detection unit at the front end and the guide member are tertiary. By moving originally, there is a possibility that the front end may bend or shake due to the weight or inertial force. Therefore, it is conceivable to use metal as a material with high strength and rigidity. However, when metal is used for the guide member, radiation is absorbed or reflected, and the radiation dose can be accurately detected by the detection unit. There is a problem that disappears.

  According to the present invention, the guide member having the detection portion for detecting radiation at the front end attached via the support rod is moved in the left-right direction by the first drive mechanism, in the up-down direction by the second drive mechanism, and further, the third drive mechanism. Can be moved in the front-rear direction by appropriately controlling the drive by each drive mechanism, so that the detection part at the front end of the guide member can be freely moved in a three-dimensional manner within the phantom. A radiation dose measuring device that operates three-dimensionally (hereinafter also simply referred to as a radiation dose measuring device), and the movement of the detector at the front end of the guide member (support rod) is closer to the movement of the human body. It can be.

  In addition, since the guide member is formed in a cylindrical shape with synthetic resin, it can be made difficult to bend by increasing the rigidity of the guide member as compared with the case where it is simply a rod-like member, and it is detected at the front end. The moving position accuracy of the part can be improved, and the transparency to the radiation can be sufficiently ensured, so that it is possible to avoid the obstacle when detecting the radiation by the detecting part. Further, since the guide member is supported by a slide holding member attached to the front end side of the third rail in addition to the rear end, the guide member is moved when the guide member is moved in the front-rear direction by the third drive mechanism. The position accuracy of the detection unit can be increased by suppressing as much as possible the swinging of the front end (detection unit) of the guide member.

  Furthermore, since the support rod is inserted and supported inside the guide member, the rigidity of the guide member can be further increased by inserting the support rod, and the guide member can be made difficult to bend. In addition, since the support rod having the detection unit attached to the front end is detachably supported from the rear side of the guide member, the detection unit can be detached from the rear side of the guide member together with the support rod through the cylinder of the guide member. The detection unit can be easily replaced without separating the phantom and the radiation dose measuring device.

  In addition, as described above, since the moving position accuracy of the detector that moves three-dimensionally can be increased, it is possible to check and verify the irradiation position and irradiation timing of the radiation treatment apparatus with high accuracy. Therefore, it is possible to follow the moving tumor with certainty, improve the results of the radiotherapy treatment with the radiotherapy device, maintain the radiotherapy device sufficiently, and be in the best condition. Can be maintained.

  Furthermore, the detector at the front end can be moved three-dimensionally, and the radiation dose measuring device is arranged behind the phantom, so that the radiation dose can be applied to tumors formed anywhere on the human body. The measuring apparatus can cope with the radiotherapy apparatus without obstruction, and can be highly versatile and easy to use. In addition, since the apparatus main body has a frame shape, the entire radiation dose measuring apparatus can be reduced in weight, can be easily carried, and can be easily placed on a bed such as a radiotherapy apparatus.

  In addition, the detection unit attached to the front end of the support rod can be moved three-dimensionally through the guide member by the first drive mechanism, the second drive mechanism, and the third drive mechanism. By simply changing the control program to be controlled, it is possible to easily change the movement of the detection unit, to make it highly versatile, and to reduce the cost for changing the movement of the detection unit. .

  Further, since the front end detection unit can be accurately moved in three dimensions, the position of the front end detection unit can be accurately grasped, and the detection unit is moved to the internal tissue of the human body by a radiographic image device such as CT. By taking an image while looking at it, it can be used for verification of the radiographic image apparatus, and the radiographic image apparatus can be maintained (calibrated) in a good state.

  In addition to the above-described configuration, the radiation dose measuring device operating three-dimensionally in the phantom of the present invention includes a “detection unit capable of detecting radiation and a composition covering and covering the detection film. It includes a spherical simulated portion formed of resin, and an attachment holding member that covers the entire simulated portion and can be attached to the front end of the support rod, and is formed of a material different from that of the simulated portion. '' It may be characterized.

  Here, the “simulation unit” includes “two hemispheres that are covered by sandwiching a detection film between the hemispheres”, “a sphere having a slit, and the detection film is placed in the slit. What was covered by inserting ", etc. are mentioned. The “synthetic resin” that forms the simulated portion includes “acrylic resin”, “polycarbonate resin”, “ABS resin”, “polypropylene”, “polyarylate resin”, “methacrylic resin”, “PEEK (polyether Ether / ketone) ”,“ polyamide resin ”, and the like, and it is desirable to use the same resin as the guide member and the support rod.

  Examples of the “material different from the simulated portion” in the attachment holding member include “bark such as cork oak”, “natural resin”, “natural rubber”, “wood”, etc., in addition to the above-described synthetic resin. It is desirable to use a material substantially equivalent to the human body with respect to radiation. For example, when simulating a tumor formed in the lungs of the human body, it is desirable to use “cork” as the material.

  By the way, when the attachment holding member is formed of the same material as the simulation part, when a radiographic image is taken by CT or the like, the boundary between the simulation part and the attachment holding member becomes unclear, and the simulation part is accurate. There is a possibility that the position becomes unknown and cannot be used for verification and calibration of a radiographic image device such as CT.

  On the other hand, the simulated part imitates a tumor formed on a human body and the like and needs to be sized according to the size of the tumor. Therefore, when the simulated part is directly attached to the support rod, the support rod There arises a problem that the size of the attachment portion on the side must be adjusted to the size of the tumor portion. Therefore, it is necessary to prepare in advance a plurality of support rods having attachment portions according to the size of the tumor, which increases the cost.

  According to the present invention, the detection unit for detecting radiation includes a simulation unit that covers the detection film and is formed of a synthetic resin, and an attachment holding member that is formed of a material different from the simulation unit and is attached to the front end of the support rod. Therefore, when a radiographic image such as CT is taken, the boundary between the simulated part as a tumor and the attachment holding member can be clearly copied due to the difference in the material formed between the simulation part and the attachment holding member. It can be set as the radiation dose measuring apparatus which can fully respond | correspond with the verification and calibration concerning an apparatus or radiotherapy.

  In addition, since the simulated part is attached to the support rod via the attachment / holding member, an attachment / holding member that matches the size of the simulated part is required. And since the attachment holding member is small, the increase in the cost concerning verification etc. can be suppressed.

  Further, the radiation dose measuring apparatus operating three-dimensionally in a wide range within the phantom of the present invention has the above-mentioned configuration, in addition to “the support rod is rotatably supported around the axis of the guide member. It may also be characterized by

  According to the present invention, since the support rod can be rotated around the axis of the guide member, the detection unit attached to the front end of the support rod by rotating the support rod is also the axis of the guide member. It is possible to rotate around the heart, the detection unit can be directed in a direction that matches the direction of the radiation emitted from the radiotherapy apparatus, and radiation can be reliably detected.

  The support rod may be manually rotated or may be rotated using a motor, and in any case, the rotation angle of the support rod (detecting unit) can be positioned. It is desirable to make it.

  Further, the radiation dose measuring apparatus operating three-dimensionally in a wide range within the phantom of the present invention is arranged in addition to the above-described configuration, “located at the rear end of the guide member and centered on the axis of the guide member. And a fitting groove recessed in a polygon larger than the inner diameter of the guide member, and an outer shape corresponding to the inner shape of the fitting groove, which can be inserted and fitted into the fitting groove, and the rear end of the support rod It is also possible to further include a fitting piece fixed to the head.

  According to the present invention, since the fitting groove on the guide member side formed in the polygon and the fitting piece on the support rod side are fitted to each other, the fitting piece is fitted into the fitting groove. Thus, the rotation position of the support rod can be easily fixed at an angle corresponding to the number of angles of the polygon, and the rotation angle position of the detection unit can be easily positioned.

  In addition to the above-described configuration, the radiation dose measuring device operating three-dimensionally in the phantom of the present invention includes the following: “The main body of the device has a rectangular parallelepiped shape and the first rail. May be arranged along two upper and lower sides extending in the left-right direction on the front side of the apparatus main body.

  By the way, when the first rail extending in the left-right direction is arranged so as to be separated in the front-rear direction, the first base guided in the left-right direction by the pair of first rails is likely to extend in the left-right direction and the front-rear direction. When the second rail extending in the vertical direction is supported by the first base, the configuration of the first base is also changed in the vertical direction in order to support both ends of the second rail. There is a problem that the first base is enlarged and the whole radiation dose measuring device is enlarged, and the first base is enlarged, which increases the weight and becomes the first drive mechanism. Since such a load increases, there arises a problem that the first drive mechanism must be increased.

  According to the present invention, the outer shape of the apparatus main body is a rectangular parallelepiped, and the pair of first rails are arranged on two upper and lower sides on the front side of the apparatus main body, so that the first rail is guided in the left-right direction by the first rail. The base can be configured to extend vertically, and the first base can support both ends or the whole of the second rail extending vertically, and the first base can be made as small as possible. The whole radiation dose measuring device can be reduced in size.

  In addition, since the first base is guided by the pair of first rails arranged vertically, the first base is in a stable state as compared to the case where the first base is guided by one first rail. As described above, the second rail can be supported in a good state by the first base, and the second base guided by the second rail can also be guided in a stable state. Therefore, as a result, it is possible to make it difficult for the detection unit attached to the front end to shake, and it is possible to improve the movement position accuracy of the detection unit.

  Furthermore, since the outer shape of the apparatus main body is a rectangular parallelepiped, it is possible to increase the rigidity of the entire apparatus main body, and it is possible to prevent the apparatus main body from being distorted by the driving force by each driving mechanism or the reaction force of the driving force. In addition, it is possible to make it difficult for the detection unit at the front end to shake, and to easily place the apparatus main body on a bed such as a radiotherapy apparatus.

  As described above, according to the present invention, a radiation dose measuring apparatus that can accurately reproduce a movement closer to the movement of the human body, can easily replace the detection unit, and operates three-dimensionally over a wide range in the phantom. Can be provided.

It is a perspective view which shows the state which attached the radiation dose measuring apparatus which operate | moves three-dimensionally in the phantom which is one Embodiment of this invention to a radiotherapy apparatus with a phantom. It is a perspective view which shows the radiation dose measuring apparatus of FIG. (A) is a top view of the radiation dose measuring apparatus of FIG. 1, (B) is a side view of the radiation dose measuring apparatus of FIG. It is a front view of the radiation dose measuring apparatus of FIG. FIG. 3A is an AA cross-sectional view in FIG. 3B, and FIG. 3B is an easy cross-sectional view in FIG. (A) is a perspective view which shows the principal part of the radiation dose measuring apparatus of FIG. 1, (B) is a perspective view which decomposes | disassembles and shows the principal part shown to (A). It is a perspective view which decomposes | disassembles and shows the detection part in the radiation dose measuring apparatus of FIG. It is a perspective view which decomposes | disassembles and shows the detection part of the form different from the example of FIG.

  A radiation dose measuring apparatus (hereinafter also referred to as a radiation dose measuring apparatus) that operates three-dimensionally in a wide range within a phantom that is an embodiment of the present invention will be described in detail with reference to FIGS. FIG. 1 is a perspective view showing a state in which a radiation dose measuring device that operates three-dimensionally over a wide range in a phantom according to an embodiment of the present invention is attached to a radiotherapy device together with a phantom. FIG. 2 is a perspective view showing the radiation dose measuring apparatus of FIG. 3A is a plan view of the radiation dose measuring apparatus of FIG. 1, and FIG. 3B is a side view of the radiation dose measuring apparatus of FIG. FIG. 4 is a front view of the radiation dose measuring apparatus of FIG. 5A is an AA sectional view in FIG. 3B, and FIG. 5B is an E sectional view in FIG. 3B. 6A is a perspective view showing a main part of the radiation dose measuring apparatus of FIG. 1, and FIG. 6B is a perspective view showing the main part shown in FIG. FIG. 7 is an exploded perspective view showing a detection unit in the radiation dose measuring apparatus of FIG. 1.

  As shown in FIG. 1, the radiation dose measuring apparatus 10 of the present embodiment can be placed on a bed 2 associated with the radiation therapy apparatus 1. In this example, the width direction of the bed 2 is the left-right direction, the longitudinal direction of the bed 2 is the front-rear direction, the direction perpendicular to the surface of the bed 2 is the vertical direction, and the direction approaching the radiation therapy apparatus 1 is the front (front side). Will be described below.

  The radiation dose measuring apparatus 10 is placed on the bed 2 of the radiation therapy apparatus 1 and has a frame-shaped apparatus main body 12 disposed on the rear side of the phantom 3 having a space imitating a human body and movable inside. The first rail 14 supported in the apparatus body 12 and extending in the left-right direction, the first base 16 held by the first rail 14 so as to be movable in the left-right direction, and the first base 16 being driven to move in the left-right direction. A first drive mechanism 18; a second rail 20 supported by the first base 16 and extending in the vertical direction within the apparatus main body 12; a second base 22 held by the second rail 20 so as to be movable in the vertical direction; And a second drive mechanism 24 for moving and driving the second base 22 in the vertical direction.

  The radiation dose measuring apparatus 10 is supported by the second base 22 and extends in the front-rear direction within the apparatus main body 12, and the third base 28 is held by the third rail 26 so as to be movable in the front-rear direction. A third drive mechanism 30 that drives the third base 28 to move in the front-rear direction, and a rear end is supported by the third base 28, and when the third base 28 moves forward, the front end is a front phantom from the apparatus main body 12. The guide member 32 is formed in a cylindrical shape by a synthetic resin and is supported on the outer periphery of the guide member 32 so as to be slidable in the front-rear direction, and is attached to the second base 22 on the front end side of the third rail 26. A slide holding member 34, a support rod 36 inserted and supported in the guide member 32 so as to be detachable from the rear side, and formed in a rod shape by a synthetic resin, and a front end of the support rod 36. And a, a detection unit 38 for measuring the radiation dose projecting forwardly from the guide member 32 together with the eclipsed.

  The radiation dose measuring apparatus 10 is attached to the third base 28 at the position of the rear end of the guide member 32, and is fitted into a square that is centered on the axis of the guide member 32 and larger than the inner diameter of the guide member 32. A rotational positioning member 40 having a mating groove 40a and a square outer shape corresponding to the inner shape of the fitting groove 40a of the rotational positioning member 40 can be inserted and fitted into the fitting groove 40a from the rear side. And a fitting piece 42 fixed to the end (see FIG. 6).

  The phantom 3 of this example is a simulation of the chest of a human body as shown in FIG. 1, and the detection unit 38 in the radiation dose measuring device 10 can move three-dimensionally within the lung of the phantom 3. It can be done. That is, in this example, the tumor formed in the lung is targeted, and the movement of the tumor that moves by respiration is reproduced. In this example, a known linear rail is used for the first rail 14, the second rail 20, and the third rail 26.

  As shown in FIG. 2 and the like, the apparatus body 12 in the radiation dose measuring apparatus 10 of the present example has a rectangular parallelepiped shape. Specifically, a plate-like front plate 12b that forms a front surface and has a rectangular opening 12a, and a rod-like lower horizontal frame 12c that is attached to the left and right ends of the lower side of the rear surface of the front plate 12b and extends backward. A bar-like upper front frame 12d attached along the upper side of the front plate 12b, a bar-like upper horizontal frame 12e attached to the left and right ends of the rear side of the upper front frame 12d and extending rearward, and left and right lower horizontal frames 12c and the upper horizontal frame 12d are connected to each other at the rear ends of the rod-like rear vertical frame 12f extending in the vertical direction, the bar-like lower rear frame 12g connecting the lower ends of the left and right rear vertical frames 12f, And a rod-like upper and rear frame 12h that connects the upper ends of the vertical frames 12f. The apparatus main body 12 includes a plate-like bottom plate 12i attached to the lower surface.

  As shown in FIG. 5, the apparatus main body 12 has a square cross section of the upper front frame 12d, the upper horizontal frame 12e, the rear vertical frame 12f, and the upper rear frame 12h, and the lower horizontal frame 12c. The lower rear frame 12g has a cross-sectional outer shape of a rectangle in which two squares having the same size as the upper front frame 12d and the like are arranged. It has been severely disconnected. The front plate 12b of the apparatus main body 12 uses a thick plate material slightly smaller than the width of the upper front frame 12d and the like, and the rigidity of the entire apparatus main body 12 is increased.

  The first rail 14 in the radiation dose measuring apparatus 10 is composed of two rails as shown in FIG. 5 and the like, and is attached along the upper side and the lower side of the front plate 12b in the apparatus main body 12, respectively. They are arranged in parallel. As illustrated, the first base 16 is formed in a plate shape having a predetermined thickness so as to straddle the pair of first rails 14, and upper and lower ends thereof are movably held by the first rails 14, respectively. The first drive mechanism 18 is disposed in the vicinity of the upper side of the front side in the apparatus main body 12, extends in the left-right direction along the upper first rail 14, and is supported by the apparatus main body 12 so as to be rotatable. A nut member 18b that is screwed to the ball screw 18a and is attached to the first base 16, and a first drive motor 18c that is attached to the apparatus body 12 and rotationally drives the ball screw 18a. The first drive mechanism 18 can move the first base 16 in the left-right direction along the first rail 14 via the nut member 18b by rotating the ball screw 18a by the first drive motor 18c. It has become.

  Moreover, the 2nd rail 20 in the radiation dose measuring apparatus 10 is comprised by two rails, as shown to FIG. 5 (A), and is located in the left-right direction along the rear surface of the plate-shaped 1st base 16, and predetermined spacing. Installed in parallel. The second base 22 is configured such that the front end side is movably held by a pair of second rails 20, and the rear end extends in the apparatus main body 12 to the vicinity of the rear end of the apparatus main body 12. The second drive mechanism 24 is disposed on the rear side of the first base 16 in the apparatus main body 12 and extends in the vertical direction along the second rail 20 and is supported by the first base 16 so as to be rotatable. A ball screw 24a, a nut member 24b screwed to the ball screw 24a and attached to the second base 22, and a second drive motor 24c attached to the upper part of the first base 16 and rotating the ball screw 24a are provided. The second drive mechanism 24 can move the second base 22 in the vertical direction along the second rail 20 via the nut member 24b by rotating the ball screw 24a by the second drive motor 24c. It has become.

  Further, as shown in FIG. 5 and the like, the third rail 26 in the radiation dose measuring apparatus 10 is configured by two rails, and is lined up and down on one side surface of the second base 22 extending in the front-rear direction. They are attached in parallel at a predetermined interval. The upper and lower ends of the third base 28 are held movably by the third rail 26, respectively. The third drive mechanism 30 extends in the front-rear direction along the lower third rail 26 and is rotatably supported by the second base 22, and a nut screwed to the ball screw 30 a and attached to the third base 28. A member 30b (see FIG. 3B) and a third drive motor 30c that is attached to a surface of the second base 22 opposite to the surface to which the third rail 26 is attached and that rotates the ball screw 30a. I have. The third drive mechanism 30 is wound around a drive pulley 30d fixed to the rotation shaft of the third drive motor 30c, a driven pulley 30e fixed to the rear end of the ball screw 30a, the driven pulley 30e, and the drive pulley 30d. And a belt 30f.

  The third drive mechanism 30 is configured such that the rotational drive from the third drive motor 30c is transmitted to the ball screw 30a via the drive pulley 30d, the belt 30f, and the driven pulley 30e, and the nut is rotated by the rotation of the ball screw 30a. The third base 28 can move in the front-rear direction along the third rail 26 via the member 30b. In this example, the drive pulley 30d and the driven pulley 30e are toothed pulleys, and the belt 30f is a toothed belt that meshes with the toothed pulleys.

  Further, the guide member 32 in the radiation dose measuring apparatus 10 has a length slightly shorter than the length of the apparatus main body 12 in the front-rear direction, and the rear end is supported by the third base 28. Specifically, the rear portion including the rear end of the guide member 32 is supported at two locations, the vicinity of the rear end of the third base 28 and the front end of the third base 28, and the shaft center of the guide member 28 is shaken. It has become difficult. In this example, the guide member 32 is made of acrylic resin.

  As shown in FIG. 2, the slide holding member 34 is attached to the second base 22 at the position of the front end of the upper third rail 26, and includes a sliding bush 34 a through which the guide member 28 can be inserted. Yes. The sliding bush 34 a is arranged coaxially with the axis of the guide member 32, and even if the guide member 32 moves in the front-rear direction due to the movement of the third base 28, the axis of the guide member 28 does not shake. It is like that. The sliding bush 34a is formed of a known material such as a fluororesin or a polyamide resin having a low frictional resistance.

  Further, as shown in FIG. 6A, the support rod 36 in the radiation dose measuring apparatus 10 has an outer diameter substantially the same as the inner diameter of the guide member 32 and has a cylindrical front end portion having a mounting hole 36a at the front end. 36b, and a rod-shaped rod portion 36c extending rearward from the rear end of the front end portion 36b longer than the guide member 32. The support rod 36 is configured such that the detection portion 38 is detachably attached to the attachment hole 36a of the front end portion 36b, and the fitting piece 42 is fixed at a position slightly forward from the rear end of the rod portion 36c. Yes. The support rod 36 has a front end portion 36b inserted into the guide member 32, and a fitting piece 42 fixed to the rear end is fitted into the fitting groove 40a of the rotation positioning member 40. 40 and can be attached coaxially with each other, and the rotation angle position can be positioned every 90 degrees with respect to the axis of the guide member 40 by the fitting piece 42.

  Further, as shown in FIGS. 6 and 7, the detection unit 38 in the radiation dose measuring apparatus 10 includes a plate-shaped detection film 44 capable of detecting radiation, and a spherical simulation formed by a synthetic resin that covers the detection film 44. An attachment holding member 48 that covers the entire portion 46, the entire simulation portion 46, and can be attached to the front end of the support rod 36, and is formed of a material different from synthetic resin that is substantially equivalent to a human body with respect to radiation, and an attachment holding member 48 And an annular front end ring 50 that holds the front end of the front end. The simulation unit 46 of the detection unit 38 is composed of two hemispherical members divided in the vertical direction, and covers the detection film 44 with the detection film 44 interposed therebetween. In this example, the simulated portion 46 is formed of the same acrylic resin as that of the guide member 32.

  Further, as shown in FIG. 6 (B), the attachment holding member 48 of the detection portion 38 extends forward from the columnar attachment portion 48a inserted into the attachment hole 36a of the support rod 36 and the front end of the attachment portion 48a. A cylindrical main body 48b that is slightly smaller in diameter than the inner diameter of the ejection guide member 32 and covers the simulated portion 46, and a holding projection 48c that protrudes in a cylindrical shape from the front end of the main body 48b and has a smaller diameter than the main body 48b. ing. The outer diameter of the holding protrusion 48 c is substantially the same as the inner diameter of the front end ring 50. Moreover, in this example, the attachment holding member 48 is formed of cork.

  Similar to the simulation portion 38b, the attachment holding member 48 is constituted by two members divided vertically, and a hemispherical accommodation recess 48d for accommodating the simulation portion 46 is formed on each division surface. (See FIG. 7). In addition, the mounting and holding member 48 has a rear end mounting portion 48a inserted into the mounting hole 36a of the support rod 36 in a state in which the two members divided in the vertical direction are aligned with each other, and the front end ring 48 is connected to the front end holding projection 48c. By inserting 50, they are inseparable from each other.

  Although not shown, the radiation dose measuring apparatus 10 is connected to a control unit (computer) for controlling the first drive mechanism 18, the second drive mechanism 24, and the third drive mechanism 30. Thus, by executing a predetermined control program, the rotational drive of each drive motor 18c, 24c, 30c in each drive mechanism 18, 24, 30 is appropriately controlled, and the support rod 36 is attached to the tip of the guide member 32. The detection unit 38 attached via the phantom 3 can be moved three-dimensionally within the phantom 3.

  Although not described in detail, the radiation dose measuring device 10 includes a moving end detection sensor that detects moving ends on both sides of the first base 16, the second base 22, and the third base 28, respectively. When the first base 16, the second base 22, the third base 28, and the like are detected by the moving end detection sensors, the first drive mechanism 18, the second drive mechanism 24, and the third drive mechanism 30 are each detected. The rotational drive of the drive motors 18c, 24c, 30c is stopped. As a result, the first base 16, the second base 22, the third base 28 and the like can be prevented from colliding with the apparatus main body 12 and the like, and the radiation dose measuring apparatus 10 can be prevented from being damaged. It can be done. Further, the base positions of the bases 16, 22, and 28 are set (reset) by causing the bases 16, 22, and 28 to be detected by the moving end detection sensors that detect the moving ends of the bases 16, 22, and 28. Therefore, the movement accuracy of the radiation dose measuring apparatus 10 can be maintained in a good state.

  Incidentally, in the radiation dose measuring apparatus 10 of this example, the width of the apparatus body 12 in the left-right direction is about 45 cm, the height in the up-down direction is about 35 cm, and the depth in the front-rear direction is about 40 cm. Further, the movable range of the detection unit 38 at the front end is about 150 mm in the left-right direction, about 250 mm in the up-down direction, and about 350 mm in the front-back direction. The cylindrical guide member 32 has an outer diameter of about 30 mm. Furthermore, the weight of the radiation dose measuring apparatus 10 is about 15 kg.

  Next, operation | movement of the radiation dose measuring apparatus 10 of this embodiment, etc. are demonstrated. First, in the first drive mechanism 18 that drives the first base 16 to move in the left-right direction, when the first drive motor 18c is driven to rotate, the ball screw 18a connected to the rotation shaft of the first drive motor 18c rotates. The nut member 18b screwed with the ball screw 18a tries to rotate together by the rotation of the ball screw 18a, but the nut member 18b is attached to the first base 16 so as not to rotate. The first base 16 is guided by the first rail 14 and moved in the left-right direction.

  Further, in the second drive mechanism 24 that drives the second base 22 to move up and down, when the second drive motor 24c is driven to rotate, the ball screw 24a connected to the rotation shaft of the second drive motor 24c rotates. As the ball screw 24a rotates, the nut member 24b screwed with the ball screw 24a tries to rotate together. However, since the nut member 24b is non-rotatably attached to the second base 22, the nut member 24b is connected to the ball screw 24a. Accordingly, the second base 22 is guided by the second rail 20 and moved in the vertical direction.

  Further, in the third drive mechanism 30 that moves and drives the third base 28 in the front-rear direction, when the third drive motor 30c is driven to rotate, the drive pulley 30d fixed to the rotation shaft of the third drive motor 30c rotates, The driven pulley 30e rotates through a belt 30f wound around the driving pulley 30d and a driven pulley 30e fixed to the rear end of the ball screw 30a. Then, when the ball screw 30a rotates together with the driven pulley 30e, the nut member 30b screwed with the ball screw 30a tries to rotate together, but the nut member 30b is attached to the third base 28 so as not to rotate. The nut member 30b moves along the ball screw 30a, and the third base 28 is guided by the third rail 26 and moved in the front-rear direction.

  Further, the guide member 32 having the detection unit 38 attached to the front end via the support rod 36 has the rear end supported by the third base 28, and as described above, the third drive motor 30c in the third drive mechanism 30. When the third base 28 moves in the front-rear direction by the rotational drive, the guide member 32 moves in the front-rear direction together with the support rod 36 and the detection unit 38. The guide member 32 is slidably held by a slide holding member 34 disposed at the front end of the third rail 26 on the front side of the rear end portion supported by the third base 28. It can move straight with respect to the axis. Further, in the slide holding member 34, the entire circumference of the outer periphery of the guide member 32 is held by the cylindrical slide bush 34a, so that the guide member 32 can be smoothly moved without shaking or rattling. It can be moved.

  In the radiation dose measuring apparatus 10 of this example, it is attached to the front end of the guide member 32 by controlling the rotational drive of the first drive motor 18c, the second drive motor 24c, and the third drive motor 30c by a control unit (not shown). The detected unit 38 can be freely moved three-dimensionally within a predetermined range in the vertical direction and the front-rear direction. Therefore, for example, when a tumor formed in the lung as a human organ is targeted, the position of the tumor moves with respiration, so that the movement of the tumor is analyzed, and the drive program for each motor 18c, 24c, 30c (Control program) is created, and by controlling the rotational drive of each motor 18c, 24c, 30c based on the control program, the simulation unit 46 in the detection unit 38 attached to the front end of the guide member 32 is actually It is now possible to accurately reproduce the same movements as other tumors.

  Moreover, in the radiation dose measuring apparatus 10 of this example, the support rod 36 is attached to the guide member 32 in a detachable state, and the support rod 36 is pulled from the guide member 32 by pulling the support rod 36 rearward. It can be removed. Further, since the maximum outer diameter of the detection unit 38 attached to the front end of the support rod 36 is smaller than the inner diameter of the guide member 32, it can be removed from the guide member 32 together with the support rod 36. ing.

  On the other hand, when attaching the support rod 36 to the guide member 32, the support rod 36 is inserted into the guide member 36 from the rear side of the guide member 36 with the detection unit 38 as the front side. And the fitting piece 42 fixed to the rear end of the support rod 36 is fitted with the fitting groove 40a of the rotation positioning member 40 arranged at the rear end of the guide member 32, whereby the support rod 36 is fitted to the guide member. It can be attached to 32 in a state in which it cannot rotate in the direction around its axis. Further, since the fitting piece 42 attached to the rear end of the support rod 36 is larger than the inner diameter of the guide member 32, the fitting piece 42 abuts against the rear end of the guide member 32, and the support rod 36 with respect to the guide member 32. The movement to the front of the vehicle can be restricted.

  The front end portion 36 b of the support rod 36 has an outer diameter that is substantially the same as the inner diameter of the guide member 32, so that the support rod 36 does not rattle inside the guide member 32. Further, when the fitting piece 42 of the support rod 36 is fitted into the fitting groove 40a, the support rod 36 can be rotated around the axis by a predetermined angle to be fitted into the fitting groove 40a. Then, since the fitting groove 40a and the fitting piece 42 are each square, the support rod 36, that is, the detection portion 38 at the front end is positioned at a rotational position every 90 degrees with respect to the axis center of the guide member 36. Be able to.

  Further, the detection unit 38 attached to the front end of the support rod 36 can be detached from the support rod 36 by moving forward from the support rod 36. Further, when the front end ring 50 inserted into the front end is removed, the attachment holding member 48 of the detection unit 38 can be divided into two, and the detection unit sandwiched between the simulation unit 46 and the simulation unit 46 housed therein. The film 44 can be removed.

  On the other hand, when assembling the detection unit 38, a pair of attachments are made such that the new detection film 44 is sandwiched between the pair of simulation parts 46 and the simulation part 46 is accommodated in the accommodation recess 48 d of the attachment holding member 48. The holding members 48 are aligned. Then, the mounting portion 48a on the rear end side of the combined mounting holding member 48 is inserted into the mounting hole 36a formed at the front end of the support rod 36, and the front end ring 50 is inserted into the front end holding projection 48c. Thus, the detection unit 38 is assembled and at the same time it is attached to the front end of the support rod 36.

  In this example, since the simulation unit 46 in the detection unit 38 has a spherical shape, when the simulation unit 46 is accommodated and held in the accommodation recess 48d of the attachment holding member 48, the split surface of the simulation unit 46, that is, the detection is detected. The direction of the film 44 can be clamped in a desired direction. The shaft 44 extends around the axis of the guide member 32 (an axis extending in the front-rear direction) by the fitting piece 42 and the fitting groove 40a at the rear end of the support rod 36. In addition to the rotation position around the center, the detection film 44 can be directed in an arbitrary direction.

  Moreover, in this example, since the attachment holding member 48 of the detection part 38 is formed of cork, it is attached by being press-fitted into the attachment hole 36a of the support rod 36 or the front end ring 50 by the elastic force of the cork. Thus, even if the guide member 32 moves, the detection unit 38 is prevented from being detached from the front end of the support rod 36.

  As described above, according to the radiation dose measuring device 10 of the present embodiment, the guide member 32 having the detection unit 38 that detects radiation at the front end attached thereto via the support rod 36 is moved in the left-right direction by the first drive mechanism 18. Since it can be moved in the vertical direction by the second drive mechanism 24 and further in the front-rear direction by the third drive mechanism 30, the front end of the guide member 32 can be controlled by appropriately controlling the drive by each drive mechanism 18, 24, 30. Can be freely moved three-dimensionally in the phantom 3, the radiation dose measuring device 10 operating in a three-dimensional manner in the phantom 3 can be provided, and the front end of the guide member 32 can be provided. The movement of the detection unit 38 can be closer to the movement of the human body.

  Further, since the guide member 32 is made of acrylic resin in a cylindrical shape, the guide member 32 can be made difficult to bend by increasing the rigidity of the guide member 32 as compared with a simple rod-like member, and is attached to the front end. In addition, it is possible to increase the accuracy of the movement position of the detection unit 38 and to ensure sufficient transparency to radiation, and to prevent the detection unit 38 from hindering the detection of radiation.

  Further, since the guide member 32 is supported by the slide holding member 34 attached to the front end side of the third rail 26 in addition to the rear end, the guide member 32 is moved in the front-rear direction by the third drive mechanism 30. In this case, the guide member 32 can be made difficult to shake, and the position accuracy of the detection unit 38 can be improved by suppressing the swing of the detection unit 38 at the front end of the guide member 32 as much as possible.

  Further, since the support rod 36 having the detection unit 38 attached to the front end is supported so as to be detachable from the rear side of the guide member 32, the detection unit 38 is moved to the rear side together with the support rod 36 through the cylinder of the guide member 32. The detection unit 38 can be easily exchanged without separating the phantom 3 and the radiation dose measuring device 10.

  Further, as described above, since the moving position accuracy of the detection unit 38 that moves three-dimensionally can be increased, the irradiation position and the irradiation timing of the radiation therapy apparatus 1 can be confirmed and verified with high accuracy. It is possible to follow the radiation with respect to the moving tumor with certainty, improve the results of the radiotherapy treatment by the radiotherapy apparatus 1, and sufficiently maintain the radiotherapy apparatus 1, It can be maintained in the best condition.

  In addition, the front end detection unit 38 can be moved three-dimensionally, and the radiation dose measuring device 10 is disposed on the rear side of the phantom 3, so that it can be applied to a tumor formed anywhere on the human lung. However, the radiation dose measuring device 10 can cope with the radiation therapy device 1 without interfering with it, and can be highly versatile and easy to use.

  In addition, since the apparatus main body 12 has a frame shape, the radiation dose measuring apparatus 10 as a whole can be reduced in weight, can be easily carried, and can be easily placed on the bed 2 of the radiation therapy apparatus 1 or the like. it can.

  Furthermore, the first drive mechanism 18, the second drive mechanism 24, and the third drive mechanism 30 can move the detection unit 38 attached to the front end of the support rod 36 via the guide member 32 in a three-dimensional manner. The movement of the detection unit 38 can be easily changed simply by changing the control program for controlling each of the drive mechanisms 18, 24, and 30, and the detection unit 38 can be made highly versatile. The cost for changing the movement of the can be reduced.

  Moreover, according to the radiation dose measuring apparatus 10 of this embodiment, while making the external shape of the apparatus main body 12 into a rectangular parallelepiped shape, a pair of 1st rail 14 is arrange | positioned at two upper and lower sides in the front side of the apparatus main body 12, and a 1st rail Since the first base 16 guided in the left-right direction by 14 is configured to extend in the vertical direction, the entire second rail 20 extending in the vertical direction can be supported by the first base 16. The movement accuracy of the second base 22 moved by the second rail 20 can be increased, the first base 16 and the like can be made as small as possible, and the radiation dose measuring apparatus 10 as a whole can be made smaller. Can do.

  Further, the first rail 14, the second rail 20, and the third rail 26 are each paired to guide the first base 16, the second base 22, and the third base 28 so as to be movable. Therefore, compared with the case where the base is guided by one rail, the bases 16, 22, and 28 can be guided in a stable state without rattling, and the detection unit 38 attached to the front end of the guide member 32 is provided. It is possible to make it difficult to shake, and it is possible to improve the movement position accuracy of the detection unit 38.

  Furthermore, since the outer shape of the apparatus main body 12 is a rectangular parallelepiped, the rigidity of the entire apparatus main body 12 can be increased, and the apparatus main body 12 is driven by the driving force by each driving mechanism 18, 24, 30 or the reaction force of the driving force. Distortion can be prevented, the front end detection unit 38 can be made difficult to swing, and the apparatus main body 12 can be easily placed on the bed 2 of the radiotherapy apparatus 1.

  Further, the support rod 36 can be rotated around the axis of the guide member 32, and the rotation position of the support rod 36 can be easily fixed by fitting the fitting piece 42 into the fitting groove 40a. Therefore, the rotation angle position of the detection unit 38 can be easily positioned, and the detection unit 38 can be oriented in a direction that matches the direction of the radiation emitted from the radiation therapy apparatus 1, thereby ensuring the radiation. Can be detected.

  Furthermore, since the detection unit 38 for detecting radiation is composed of a simulation unit 46 that covers the detection film 44 and is formed of acrylic resin, and an attachment holding member 48 that covers the simulation unit 46 and is formed of cork, such as CT When a radiographic image is taken, the boundary between the simulated portion 46 as a tumor and the attachment holding member 48 can be clearly copied due to the difference in the materials forming the simulation portion 46 and the attachment holding member 48. It can be set as the radiation dose measuring apparatus 10 which can fully respond | correspond with the verification and calibration concerning an apparatus or radiotherapy.

  Further, since the simulation unit 46 in the detection unit 38 is attached to the support rod 36 via the attachment holding member 48, the attachment holding member 48 that matches the size of the simulation unit 46 is required. Compared with the case where a large number of the entire 36 is prepared, the attachment holding member 48 is sufficiently small, so that an increase in cost for verification or the like can be suppressed.

  The present invention has been described with reference to preferred embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made without departing from the spirit of the present invention as described below. And design changes are possible.

  That is, in the above-described embodiment, the phantom 3 is a model that simulates the chest of a human body and is intended for a tumor formed in the lung. However, the present invention is not limited to this, and the phantom 3 Other sites such as heads and heads may be simulated, and tumors formed in other organs may be targeted.

  In the above-described embodiment, the fitting groove 40 a and the fitting piece 42 for positioning the rotation position around the axis of the guide member 32 in the support rod 36 (detection unit 38) are used as the axis of the guide member 32. Although the shape formed in the center square was shown, it is not limited to this, and it may be a regular triangle or a regular polygon more than a regular pentagon, and the same effect as described above can be achieved.

  Furthermore, in the above-described embodiment, the detection unit 38 is shown in which the detection unit 44 is sandwiched by the simulation unit 46. However, the detection unit 38 is not limited to this, and instead of the detection unit 44, as shown in FIG. A radiation detection sensor may be provided. Specifically, FIG. 8 is an exploded perspective view showing a detection unit having a different form from the example of FIG. In addition, about the structure similar to the above, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted. The detection unit 39 shown in FIG. 8 has a bar-shaped detection sensor 52 (pinpoint dose) having a reaction part 52a that reacts to radiation such as a scintillator at the front end inserted into the simulation part 46. Total).

  Further, as shown in FIG. 8, in the attachment holding member 48, the shape of the accommodation recess 48 d is a shape corresponding to the simulation portion 46 and the detection sensor 52. Although not shown, a connection cable extends from the rear end of the detection sensor 52, extends to the rear side of the guide member 32 through the support rod 36, and is connected to a predetermined device. . By using this detection unit 39, it is possible to detect radiation emitted from the radiation therapy apparatus 1 or the like in real time, and to save time and effort for verification and calibration of the radiation therapy apparatus 1, radiation imaging apparatus, and radiation therapy. It can be simplified.

  Furthermore, in the above-described embodiment, the radiation dose measuring device 10 is placed on the bed 2 of the radiation therapy device 1. However, the present invention is not limited to this. For example, the radiation dose measuring device 10 may be mounted on a radiation imaging device bed such as a CT. Accordingly, in the radiation dose measuring apparatus 10 described above, the front end detection unit 38 can be accurately moved three-dimensionally as described above, and the position of the front end detection unit 38 can be determined. Since it can be accurately grasped, it can be used for verification of the radiographic apparatus by imaging the detection unit 38 as an internal tissue of a human body with a radiographic apparatus such as CT, and the radiographic apparatus is in a good state. Can be maintained (calibrated).

  When the radiation dose measuring device 10 is used in a radiographic image device, a detection unit 38 that detects radiation is formed by a simulation unit 46 that covers the detection film 44 and is formed of acrylic resin, and a simulation unit 46 that covers the simulation unit 46 and is formed of cork. When the radiographic image is taken, the simulated portion 46 as the tumor and the attachment holding member 48 are different due to the difference in the materials forming the simulation portion 46 and the attachment holding member 48. The boundary of the image can be clearly copied, and the radiographic image apparatus can be sufficiently verified and calibrated.

DESCRIPTION OF SYMBOLS 1 Radiation therapy apparatus 2 Bed 3 Phantom 10 Radiation dose measuring apparatus 12 Apparatus main body 14 First rail 16 First base 18 First drive mechanism 20 Second rail 22 Second base 24 Second drive mechanism 26 Third rail 28 Third base 30 Third drive mechanism 32 Guide member 34 Slide holding member 36 Support rod 38 Detection unit 39 Detection unit 40 Rotation positioning member 40a Fitting groove 42 Fitting piece 44 Detection film 46 Simulation unit 48 Mounting holding member 50 Front end ring 52 Detection sensor

Japanese Patent Laid-Open No. 7-80089

Claims (5)

A frame-shaped device body placed on the back of a phantom placed on the bed of a radiotherapy device or radiographic image device and imitating a human body and having a space inside;
A first rail supported in the apparatus body and extending in the left-right direction;
A first base held movably in the left-right direction by the first rail;
A first drive mechanism for moving the first base in the left-right direction;
A second rail supported by the first base that is driven to move in the left-right direction by the first drive mechanism, and extending in the up-down direction within the apparatus body;
A second base held movably in the vertical direction by the second rail;
A second drive mechanism for moving the second base in the vertical direction;
A third rail supported by the second base that is driven to move up and down by the second drive mechanism, and extending in the front-rear direction in the apparatus body;
A third base held movably in the front-rear direction by the third rail;
A third drive mechanism for moving the third base in the front-rear direction;
The rear end is supported by the third base that is driven to move in the front-rear direction by the third drive mechanism, and when the third base moves forward, the front end can protrude from the apparatus main body into the front phantom. A guide member formed in a cylindrical shape with a synthetic resin;
A slide holding member that supports the outer periphery of the guide member so as to be slidable in the front-rear direction, and is attached to the second base on the front end side of the third rail;
A support rod that is inserted and supported in a removable manner from the rear side in the guide member supported by the slide holding member and the third base, and is formed in a rod shape by a synthetic resin;
A radiation dose measuring device that is attached to the front end of the support rod, protrudes forward from the guide member, and has a detection unit for measuring the radiation dose, and operates in a wide range three-dimensionally within the phantom. .
The detector is
A detection film capable of detecting radiation;
A spherical simulated portion formed of a synthetic resin covering the detection film;
The phantom according to claim 1, further comprising an attachment holding member that covers the entire simulation portion and can be attached to a front end of the support rod, and is formed of a material different from that of the simulation portion. A radiation dose measuring device that operates three-dimensionally over a wide range. The support rod is
3. The radiation dose measuring device operating three-dimensionally over a wide range in the phantom according to claim 1, wherein the radiation amount measuring device is supported so as to be rotatable around an axis of the guide member. A fitting groove which is disposed at the rear end of the guide member and is recessed in a polygon which is centered on the axis of the guide member and which is larger than the inner diameter of the guide member;
A fitting piece that can be inserted and fitted into the fitting groove with an outer shape corresponding to an inner shape of the fitting groove and is fixed to a rear end of the support rod. 3. A radiation dose measuring apparatus that operates three-dimensionally in a wide range within the phantom described in 3. The apparatus main body is
The outer shape is formed in a rectangular parallelepiped shape,
The first rail is
5. The phantom according to claim 1, which is arranged along the two upper and lower sides extending in the left-right direction on the front side of the apparatus main body over a wide range. Radiation dose measuring device that operates originally.

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