JP2020048811A - Neutron capture therapy system - Google Patents

Abstract

To provide a neutron capture therapy system capable of improving position accuracy of a patient with respect to a neutron beam irradiation part.SOLUTION: A position detection system 120 can acquire a position of a first marker part 124 quantitatively in a state that an interference between devices is avoided since the position detection is performed by using an electromagnetic wave. Therefore, the position detection system 120 can acquire a position of a patient S in three-dimensional coordinates quantitatively on the basis of the position of the first marker part 124. Thus, the position detection system 120 can determine whether or not the patient S is deviated with respect to a neutron beam irradiation part 20 three-dimensionally and quantitatively, and, if it is deviated, can acquire a direction and an amount of the deviation quantitatively.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a neutron capture therapy system.

  BACKGROUND ART As a neutron capture therapy system that irradiates a patient with a neutron beam, one described in Patent Literature 1 is known. This neutron capture therapy system includes a mounting table on which a patient is mounted, and a neutron irradiation unit that irradiates a neutron beam to the patient mounted on the mounting table. Positioning of the patient placed on the mounting table with the neutron irradiation unit is performed using a laser sensor.

JP-A-2015-231497

  In the above-mentioned neutron capture therapy system, since the position of the patient is adjusted using the laser sensor, the position accuracy cannot be quantified. Thus, there is room for improvement in patient positioning.

  The present invention has been made in view of the above, and an object of the present invention is to provide a neutron capture therapy system that can improve the positional accuracy of a patient with respect to a neutron irradiation unit.

  In order to achieve the above object, a neutron capture therapy system according to one embodiment of the present invention is a neutron capture therapy system that irradiates a patient with a neutron beam, and a mounting table on which the patient is mounted, and a mounting table mounted on the mounting table. A neutron beam irradiation unit that irradiates a neutron beam to the patient, and a position detection unit that detects the position of the patient, the position detection unit emits a first electromagnetic wave toward the mounting table, A first marker unit attached to a patient placed on the mounting table, for reflecting the first electromagnetic wave from the emission unit, or receiving the first electromagnetic wave and emitting a second electromagnetic wave different from the first electromagnetic wave; And a calculation unit that obtains a reflected wave from the first marker unit or a second electromagnetic wave and calculates the position of the first marker unit in three-dimensional coordinates.

  The neutron capture therapy system includes a position detection unit that detects the position of the patient. The position detection unit is configured to emit a first electromagnetic wave toward the mounting table, and to be attached to a patient mounted on the mounting table, to reflect the first electromagnetic wave from the emission unit or to generate the first electromagnetic wave. A first marker unit that receives and emits a second electromagnetic wave different from the first electromagnetic wave, and a reflected wave or a second electromagnetic wave from the first marker unit, and obtains a first marker in three-dimensional coordinates And a calculation unit for calculating the position of the unit. For example, when trying to detect a patient placed on a mounting table with a CT device, the measurement cannot be performed because the CT device and the neutron irradiation unit interfere with each other. On the other hand, since the position detection unit performs position detection using electromagnetic waves, it is possible to quantitatively acquire the position of the first marker unit in a state where interference between devices as described above is avoided. Therefore, the position detection unit can quantitatively acquire the position of the patient in the three-dimensional coordinates based on the position of the first marker unit. With this, the position detection unit can quantitatively determine whether the patient is shifted with respect to the neutron irradiation unit in a three-dimensional manner, and if so, quantitatively determines the direction and amount of the shift. Can be obtained. As described above, the positional accuracy of the patient with respect to the neutron irradiation unit can be improved.

  The position detection unit is attached to at least one of the neutron beam irradiation unit and the mounting table, reflects the first electromagnetic wave from the emission unit, or receives the first electromagnetic wave to generate a third electromagnetic wave different from the first electromagnetic wave. The image processing apparatus may further include a second marker unit that emits light, and the calculation unit may obtain a reflected wave from the second marker unit or a third electromagnetic wave, and calculate a position of the second marker unit in three-dimensional coordinates. . In the neutron capture therapy system, the positions of the neutron irradiation unit and the mounting table are fixed during the treatment. Therefore, the position detection unit can quantitatively acquire the position of the neutron irradiation unit in three-dimensional coordinates based on the position of the second marker unit. This makes it easier for the position detection unit to determine the deviation of the patient from the neutron beam irradiation unit.

  The calculation unit may calculate a relative positional relationship between the patient and the neutron irradiation unit based on the position of the first marker unit and the position of the second marker unit. Accordingly, the position detection unit can determine the deviation of the patient from the neutron irradiation unit based on the relative positional relationship between the patient and the neutron irradiation unit in the three-dimensional coordinates.

  The emission unit may emit infrared light as the first electromagnetic wave, and the first marker unit may reflect the infrared light. By using infrared rays as the electromagnetic waves, the position of the first marker portion can be accurately obtained without affecting devices.

  At least two second marker portions may be provided on the surface of the irradiation hole that allows the neutron beam to pass through, or the wall portion where the irradiation hole is formed, of the neutron beam irradiation. In this case, the calculation unit can accurately acquire the center point of the irradiation hole based on at least two second marker portions near the irradiation hole from which the neutron beam is emitted. By determining the deviation of the patient from the center point of the irradiation hole, the patient can be more accurately irradiated with the neutron beam.

  A neutron capture therapy system according to one aspect of the present invention is a neutron capture therapy system that irradiates a patient with a neutron beam, and a mounting table on which the patient is mounted, and a neutron beam to the patient mounted on the mounting table. It includes a neutron irradiation unit for irradiation and a position detection unit for detecting a position of a patient, and the position detection unit is configured by a motion capture system.

  The neutron capture therapy system includes a position detection unit that detects the position of the patient. The position detection unit is configured by a motion capture system. For example, when trying to detect a patient placed on a mounting table with a CT device, the measurement cannot be performed because the CT device and the neutron irradiation unit interfere with each other. On the other hand, the motion capture system can quantitatively acquire the position of the patient in three-dimensional coordinates while avoiding the interference between the devices as described above. With this, the position detection unit can quantitatively determine whether the patient is shifted with respect to the neutron irradiation unit in a three-dimensional manner, and if so, quantitatively determines the direction and amount of the shift. Can be obtained. As described above, the positional accuracy of the patient with respect to the neutron irradiation unit can be improved.

  ADVANTAGE OF THE INVENTION According to this invention, the neutron capture therapy system which can improve the positional accuracy of a patient with respect to a neutron irradiation part can be provided.

It is a block configuration diagram of a treatment system provided with a neutron capture therapy system according to an embodiment of the present invention. It is a figure showing composition of a neutron capture therapy system concerning an embodiment of the present invention. FIG. 3 is a diagram illustrating the vicinity of a neutron irradiation unit in the neutron capture therapy system in FIG. 2. It is the figure which looked at the neutron beam irradiation part from the irradiation room side. FIG. 3 is an enlarged view showing a positional relationship between a collimator and a patient. 5 is a flowchart illustrating a process in a calculation unit. It is a figure showing a method of judging a gap of a position of a patient.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same elements will be denoted by the same reference symbols, without redundant description.

  With reference to FIG. 1, a schematic configuration of a treatment system 150 including a neutron capture therapy system 100 according to the present embodiment will be described. As shown in FIG. 1, the treatment system 150 includes a treatment planning device 130 and a neutron capture therapy system 100. The neutron capture therapy system 100 is a system that performs treatment by neutron capture therapy in which a patient S is irradiated with a neutron beam N.

  The treatment planning device 130 is a device that creates in advance a treatment plan on how to irradiate a neutron beam to the patient S. The treatment planning device 130 grasps the position of the tumor of the patient S from a CT image or the like, and also determines the posture of the patient to irradiate the tumor with a neutron beam. The treatment planning device 130 transmits the created treatment plan to the neutron capture therapy device 110. Thereby, the neutron capture therapy device 110 irradiates a neutron beam based on the treatment plan.

  The neutron capture therapy system 100 includes a neutron capture therapy device 110 and a position detection system 120 (position detection unit). The neutron capture therapy device 110 is a device that performs treatment by neutron capture therapy based on the treatment plan set by the treatment plan device 130. The position detection system 120 is a system that detects the position of the patient S. The position detection system 120 can detect a relative positional relationship between the patient S and the neutron capture therapy device 110 during treatment.

The outline of the neutron capture therapy system 100 will be described with reference to FIGS. 2 and 3. As shown in FIGS. 2 and 3, the neutron capture therapy device for performing cancer treatment using boron neutron capture therapy is configured such that a neutron captures a site where boron is accumulated in a patient S to which a drug containing boron ( ¹⁰ B) is administered. It is a system that performs cancer treatment by irradiating a ray. The treatment by the neutron capture therapy device 110 is performed in the irradiation room 2 for irradiating the patient S restrained by the mounting table 3 with the neutron beam N.

  Preparation work such as restraining the patient S on the mounting table 3 is performed in a preparation room (not shown) outside the irradiation room 2, and the mounting table 3 with the patient S restrained is moved from the preparation room to the irradiation room 2. . Thereafter, the mounting table 3 is installed at a predetermined position in front of the emission port of the irradiation chamber 2. The neutron capture therapy device 110 is mounted on the mounting table 3 on which the patient S is mounted, the neutron beam generator 10 for generating the neutron beam N for treatment, and mounted on the mounting table 3 in the irradiation room 2. A neutron beam irradiator 20 for irradiating the patient S with the neutron beam N. Although the irradiation chamber 2 is covered with the shielding wall W, a passage and a door 41 are provided for passing a patient, an operator, or the like.

  The neutron beam generator 10 scans the charged particle beam L by accelerating the charged particle and emitting the charged particle beam L, the beam transport path 12 for transporting the charged particle beam L emitted by the accelerator 11, and the like. A charged particle beam scanning unit 13 for controlling the irradiation position of the charged particle beam L on the target 8; a target 8 for generating a neutron beam N by causing a nuclear reaction by irradiating the charged particle beam L; And a current monitor 16 for measuring the current of L. The accelerator 11 and the beam transport path 12 are arranged in a chamber of a charged particle beam generation chamber 14 having a substantially rectangular shape, and the charged particle beam generation chamber 14 is a space covered by a concrete shielding wall W. . Note that the charged particle beam generation chamber 14 is provided with a passage and a door 42 through which an operator for maintenance passes. Note that the charged particle beam generation chamber 14 is not limited to a substantially rectangular shape, and may have another shape. For example, when the path from the accelerator to the target is L-shaped, the charged particle beam generation chamber 14 may be L-shaped. The charged particle beam scanning unit 13 controls, for example, the irradiation position of the charged particle beam L on the target 8, and the current monitor 16 measures the current of the charged particle beam L irradiated on the target 8.

  The accelerator 11 accelerates charged particles such as protons to generate a charged particle beam L such as a proton beam. In the present embodiment, a cyclotron is employed as the accelerator 11. Note that, as the accelerator 11, instead of the cyclotron, another accelerator such as another circular accelerator (for example, a synchrotron), a linear accelerator, or an electrostatic accelerator may be used.

  One end (upstream end) of the beam transport path 12 is connected to the accelerator 11. The beam transport path 12 includes a beam adjusting unit 15 that adjusts the charged particle beam L. The beam adjusting unit 15 includes a horizontal steering electromagnet and a horizontal / vertical steering electromagnet that adjust the axis of the charged particle beam L, a quadrupole electromagnet that suppresses the divergence of the charged particle beam L, and a four-way shaping the charged particle beam L. It has a slit and the like. Note that the beam transport path 12 only needs to have a function of transporting the charged particle beam L, and the beam adjusting unit 15 may not be provided.

  The charged particle beam L transported by the beam transport path 12 is irradiated to the target 8 by controlling the irradiation position by the charged particle beam scanning unit 13. Note that the charged particle beam scanning unit 13 may be omitted, and the same location of the target 8 may be always irradiated with the charged particle beam L.

  The target 8 generates a neutron beam N by being irradiated with the charged particle beam L. The target 8 is made of, for example, beryllium (Be), lithium (Li), tantalum (Ta), or tungsten (W), and has a plate shape. However, the target is not limited to a plate shape and may be a liquid or the like. The neutron beam N generated by the target 8 is irradiated by the neutron beam irradiation unit 20 toward the patient S in the irradiation room 2.

  The neutron beam irradiation unit 20 includes a moderator 21 for decelerating the neutron beam N emitted from the target 8, and a shield 22 for shielding radiation such as the neutron beam N and gamma ray from being emitted to the outside. The moderator 21 and the shield 22 constitute a moderator.

  The moderator 21 has, for example, a laminated structure composed of a plurality of different materials, and the material of the moderator 21 is appropriately selected according to various conditions such as the energy of the charged particle beam L. Specifically, for example, when the output from the accelerator 11 is a proton beam of 30 MeV and a beryllium target is used as the target 8, the material of the moderator 21 can be lead, iron, aluminum, or calcium fluoride.

  The shield 22 is provided so as to surround the moderator 21, and functions to shield the neutron beam N and gamma rays generated with the generation of the neutron beam N from being emitted to the outside of the shield 22. Having. At least a part of the shield 22 may or may not be embedded in the wall W1 separating the charged particle beam generation chamber 14 and the irradiation chamber 2. Further, between the irradiation chamber 2 and the shield 22, a wall portion 23 that forms a part of the side wall surface of the irradiation chamber 2 is provided. The wall portion 23 is provided with a collimator mounting portion 23a serving as an output port of the neutron beam N. A collimator 31 for defining the irradiation field of the neutron beam N is fixed to the collimator mounting portion 23a. The irradiation field of the neutron beam N can be defined by changing the shape of the opening in the collimator 31. The collimator 31 may be attached to the mounting table 3 without providing the collimator attachment portion 23a on the wall 23.

  In the neutron beam irradiation unit 20 described above, the target particle 8 is irradiated with the charged particle beam L, so that the target 8 generates a neutron beam N. The neutron beam N generated by the target 8 is decelerated while passing through the moderator 21, and the neutron beam N emitted from the moderator 21 passes through the collimator 31 and is mounted on the mounting table 3. The patient S is irradiated. Here, as the neutron beam N, a thermal neutron beam or an epithermal neutron beam having relatively low energy can be used.

  The position detection system 120 includes a calculation unit 121, a detection unit 122, an emission unit 123, a first marker unit 124, and a second marker unit 125. Such a position detection system 120 is configured by a motion capture system. The motion capture system is capable of digitally measuring the position and orientation of an object continuously over time.

  The emission unit 123 emits an electromagnetic wave (first electromagnetic wave) toward the mounting table 3. Thus, the emission unit 123 can apply the first electromagnetic wave to the marker units 124 and 125 existing around the mounting table 3. In the present embodiment, the emission unit 123 emits infrared rays as electromagnetic waves. The detection unit 122 detects infrared rays (hereinafter, may be referred to as reflected waves) reflected by the marker units 124 and 125. The detection unit 122 transmits information on the detected reflected wave to the calculation unit 121. In the motion capture system, the motion capture camera 127 includes the detection unit 122 and the emission unit 123. The motion capture camera 127 transmits the data acquired by shooting to the calculation unit 121. The position detection system 120 includes a plurality of motion capture cameras 127. That is, the position detection system 120 includes a plurality of pairs of the detection unit 122 and the emission unit 123. The installation location of the motion capture camera 127 will be described later.

The first marker section 124 is a member that is attached to the patient S placed on the placement table 3 and reflects infrared rays from the emission section 123. Since the first marker section 124 is attached to the patient S, the first marker section 124 moves according to a change in the position or posture of the patient S. Therefore, the first marker section 124 reflects infrared light at a position corresponding to the position and posture of the patient S in a three-dimensional space. The installation position of the first marker section 124 will be described later.

  The second marker section 125 is a member that is attached to at least one of the neutron beam irradiation section 20 and the mounting table 3 and reflects infrared rays from the emission section 123. The second marker section 125 is attached to the neutron irradiation section 20 and the third treatment which are fixed at a specific position at least during the treatment. Therefore, the second marker section 125 reflects infrared rays at a fixed position at least during treatment in a three-dimensional space. The installation position of the second marker section 125 will be described later.

  The calculation unit 121 acquires the reflected wave from the first marker unit 124 and the reflected wave from the second marker unit 125 via the detection unit 122. The calculation unit 121 calculates the positions of the marker units 124 and 125 in three-dimensional coordinates based on the acquired reflected waves. The calculation unit 121 calculates the relative positional relationship between the patient S and the neutron beam irradiation unit 20 based on the position of the first marker unit 124 and the position of the second marker unit 125. The calculation unit 121 determines the position of the plurality of first marker units 124 (124A, 124B, 124C) as shown in FIG. The position of the center of gravity GP) of the first marker section 124 may be calculated. Further, the calculation unit 121 may calculate the position of the device representative point (for example, the center point CP of the irradiation hole 31a of the collimator 31 shown in FIG. 5) based on the positions of the plurality of second marker units 125. The calculation unit 121 quantitatively (quantifies and converts) the relative positional relationship between the patient S and the neutron beam irradiation unit 20 by grasping the relative positional relationship between the patient representative point and the device representative point in three-dimensional coordinates. ) You can figure out.

  The calculation unit 121 can determine the displacement of the position of the patient S based on the relative positional relationship between the patient S and the neutron irradiation unit 20. For example, the calculation unit 121 refers to the positional relationship between the patient representative point and the device representative point, and calculates the distance in the X-axis direction, the distance in the Y-axis direction, and the distance in the Z-axis direction of the patient representative point with respect to the device representative point. If it is determined that at least one of the positions deviates from the range of the allowable value, it can be determined that the position of the patient S has deviated. Such an allowable value is set in advance before treatment. For example, a reference position (ideal position) of the patient representative point with respect to the device representative point is determined, and how much deviation from the reference position is allowable is determined for the X-axis direction, the Y-axis direction, and the Z-axis direction. . Note that such setting of the reference position may be performed by the treatment planning apparatus 130 performing a simulation using a 3D model. Alternatively, the reference position may be set by the patient S taking an actual posture at the time of the treatment before the neutron irradiation unit 20 before the treatment.

  When determining that the position of the patient S has shifted, the calculation unit 121 performs a notification process. The notification process may be performed by display on a display or guidance by voice. Alternatively, the notification process may be performed by interlocking the neutron capture therapy device 110. At this time, the calculation unit 121 can grasp the direction and the amount of the deviation from the reference position or the allowable range in the XYZ coordinates. Therefore, the calculation unit 121 may quantitatively provide information on what direction and how much the patient S should be moved.

  Next, with reference to FIG. 4 and FIG. 5, a specific installation example of the marker units 124 and 125 and a specific calculation example will be described. The second marker section 125 is preferably arranged at a position where the center point CP (see FIG. 5) of the irradiation hole 31a of the collimator 31 can be easily determined. Since the second marker part 125 cannot be installed at the center point CP of the irradiation hole 31a of the collimator 31 through which the neutron beam passes, the second marker part 125 is arranged on the surface of the irradiation hole 31a of the collimator 31 or the surface of the wall part 23. Is preferred. When the second marker section 125 is arranged on the wall section 23, it is preferable to arrange the second marker section 125 near the collimator 31. Further, it is preferable that at least two second marker portions 125 are provided in order to determine the center point CP. It is preferable that three or more second marker sections 125 are set in anticipation of the occurrence of the second marker section 125 which is obstructed by the patient S and cannot be photographed by the motion capture camera 127. In the example shown in FIG. 4, three second marker portions 125A, 125B, and 125C are provided on the surface of the wall portion 23 near the collimator 31 so as to surround the collimator 31. The second marker section 125A is provided above the collimator 31, the second marker section 125B is provided on the right side of the collimator 31, and the second marker section 125C is provided on the left side of the collimator 31.

  It is preferable that one first marker section 124 has a positional relationship such that it is photographed by at least three motion capture cameras 127. Further, it is preferable that one second marker section 125 has a positional relationship such that it is photographed by at least two, preferably three, motion capture cameras 127. For example, three motion capture cameras 127 capable of photographing three first marker parts 124 and three second marker parts 125 may be provided. However, when the marker portions 124 and 125 are hidden from the patient S or the mounting table 3 from the position of a certain motion capture camera 127, the motion capture cameras 127 that can capture images from other positions may be increased. The motion capture camera 127 is preferably arranged at a position where the marker sections 124 and 125 are not hidden by the mounting table 3 or the patient S. It is preferable that the motion capture camera 127 is disposed at a position where the motion capture camera 127 looks into the collimator 31. Therefore, it is preferable that the motion capture camera 127 is arranged at an upper portion of the collimator 31 or at a position close to the wall 23 on the side wall of the irradiation chamber 2. In the example shown in FIG. 4, the motion capture camera 127A is provided above the collimator 31 in the wall 23. The motion capture camera 127 </ b> B is provided near the wall 23 and near the ceiling in the side wall of the irradiation room 2. The motion capture camera 127 </ b> C is provided on the side wall of the irradiation room 2 near the wall 23 and near the floor.

  The first marker section 124 is attached to a site near the collimator 31 of the patient S. For example, the first marker section 124 may be provided at an ear hole, a mole, a nose head, an inner eye, or the like. It is preferable that at least three first marker portions 124 are provided so that the representative point of the patient S can be determined in the three-dimensional coordinates. In the example shown in FIG. 5, the first marker portion 124A is provided near the ear hole, the first marker portion 124B is provided near the head, and the first marker portion 124C is provided at the nose head. .

  Here, an example of the processing of the arithmetic unit 121 during the treatment will be described with reference to the flowchart in FIG. The calculation unit 121 obtains the position of the neutron irradiation unit 20 by obtaining the position of the second marker unit 125A, 125B, 125C captured by the motion capture camera 127A, 127B, 127C (step S10). At this time, the calculation unit 121 determines the center point CP of the irradiation hole 31a as a device representative point. For example, before the treatment, the positional relationship between the second marker units 125A, 125B, 125C and the center point CP is grasped in advance, and the calculation unit 121 acquires the information on the positional relationship and the second information acquired in S10. The center point CP is determined by comparing the position information of the marker units 125A, 125B, and 125C with the position information.

  Here, the calculation unit 121 sets the reference position of the patient representative point based on the position of the center point CP (Step S20). The calculation unit 121 sets a reference position by reading data that is predetermined before treatment. Next, the calculation unit 121 acquires the position of the patient S by acquiring the positions of the first marker units 124A, 124B, 124C photographed by the motion capture cameras 127A, 127B, 127C (step S30). For example, when the ideal position of the center of gravity GP is set as the reference position SP, the calculation unit 121 calculates the center of gravity GP as the patient representative point. Alternatively, when the ideal positions of the first marker sections 124A, 124B, and 124C are set as the reference positions PA, PB, and PC (see FIG. 5B), the calculation section 121 causes the first marker sections 124A, 124B. , 124C as the patient representative points.

  Next, the calculation unit 121 determines whether or not the position of the patient S is shifted by comparing the positional relationship between the reference position SP and the patient representative point (step S40). As shown in FIG. 5A, when the center of gravity GP matches the reference position SP, the calculation unit 121 determines that the position of the patient S is not shifted. On the other hand, as shown in FIG. 5B, when the center of gravity GP is located at a position different from the reference position SP, the calculation unit 121 considers the magnitude of the deviation amount and moves to the position of the patient S. It is determined whether or not there is. When the reference positions PA, PB, and PC are used, as shown in FIG. 5B, when the first marker portions 124A, 124B, and 124C are arranged at positions different from the reference positions PA, PB, and PC, calculation is performed. The unit 121 determines whether there is a shift in the position of the patient S by considering the size of the shift amount at each point.

  For example, as shown in FIG. 7A, the allowable range of the shift amount with respect to the reference position SP is defined for each of the X-axis direction, the Y-axis direction, and the Z-axis direction. When the center of gravity GP is located outside the rectangular parallelepiped set by the allowable range, the calculation unit 121 determines that the position of the patient S is shifted. Further, as shown in FIG. 7B, an allowable value of the shift amount with respect to the reference position SP is defined. The calculation unit 121 determines that the position of the patient S is displaced when the center of gravity GP is placed outside a sphere whose allowable value is set as a radius. The same applies to the case where the reference positions PA, PB, PC are used.

  If the calculation unit 121 determines in S40 that there is no deviation, it determines whether or not the treatment has been completed (step S50). When it is determined that the treatment has been completed, the processing illustrated in FIG. 6 ends. On the other hand, if it is determined that the treatment has not been completed, the processing is repeated from S30. Thus, during the treatment, the position of the patient S is constantly monitored.

  If it is determined in S40 that there is a shift, the calculation unit 121 performs a notification process indicating that there is a shift (step S60). At this time, the neutron beam irradiation may be stopped. The calculation unit 121 may display the direction in which the shift has occurred and the shift amount. When S60 ends, the process is repeated from S30 or the process shown in FIG. 6 ends once.

  Next, the operation and effect of the neutron capture therapy system 100 according to the present embodiment will be described.

  The neutron capture therapy system 100 includes a position detection system 120 that detects the position of the patient S. The position detection system 120 is attached to a patient S placed on the mounting table 3 and emits a first electromagnetic wave toward the mounting table 3, and reflects the first electromagnetic wave from the emitting section 123. It includes a first marker section 124 and a calculation section 121 that acquires a reflected wave from the first marker section 124 and calculates the position of the first marker section 124 in three-dimensional coordinates. For example, when trying to detect a patient S placed on the mounting table 3 by a CT device, the measurement cannot be performed because the CT device and the neutron irradiation unit 20 interfere with each other. Such a problem is a problem peculiar to the neutron capture therapy system in which the posture of the patient S must be fixed in a state where the patient S is close to the irradiation hole 31a of the neutron beam irradiation unit 20, even in the radiotherapy. On the other hand, since the position detection system 120 performs position detection using electromagnetic waves, it is possible to quantitatively obtain the position of the first marker unit 124 in a state where interference between the devices as described above is avoided. it can. Therefore, the position detection system 120 can quantitatively acquire the position of the patient S in three-dimensional coordinates based on the position of the first marker unit 124. Accordingly, the position detection system 120 can quantitatively determine three-dimensionally whether or not the patient S is displaced with respect to the neutron irradiation unit 20. If there is a dislocation, the direction and amount of the displacement Can be obtained quantitatively. As described above, the positional accuracy of the patient S with respect to the neutron beam irradiation unit 20 can be improved.

  The position detection system 120 further includes a second marker unit 125 attached to at least one of the neutron beam irradiation unit 20 and the mounting table 3 and reflecting the first electromagnetic wave from the emission unit 123. The reflected wave from the second marker unit 125 is obtained, and the position of the second marker unit 125 in three-dimensional coordinates is calculated. In the neutron capture therapy system 100, the positions of the neutron beam irradiation unit 20 and the mounting table 3 are fixed during the treatment. Therefore, the position detection system 120 can quantitatively acquire the position of the neutron beam irradiation unit 20 in three-dimensional coordinates based on the position of the second marker unit 125. This makes it easier for the position detection system 120 to determine the displacement of the patient S with respect to the neutron beam irradiation unit 20.

  The calculation unit 121 calculates the relative positional relationship between the patient S and the neutron beam irradiation unit 20 based on the position of the first marker unit 124 and the position of the second marker unit 125. Thus, the position detection system 120 can determine the deviation of the patient S from the neutron irradiation unit 20 based on the relative positional relationship between the patient S and the neutron irradiation unit 20 in three-dimensional coordinates.

  The emission unit 123 emits infrared light as a first electromagnetic wave, and the first marker unit 124 reflects infrared light. By using infrared rays as electromagnetic waves, the position of the first marker section 124 can be accurately acquired without affecting devices.

  At least two second marker sections 125 are provided on the surface of the irradiation hole 31a through which the neutron beam passes, or the wall 23 where the irradiation hole 31a is formed, of the neutron beam irradiation section 20. In this case, the calculation unit 121 can accurately acquire the center point CP of the irradiation hole 31a based on at least two second marker portions 125 near the irradiation hole 31a from which the neutron beam is emitted. By determining the deviation of the patient S from the center point CP of the irradiation hole 31a, the patient S can be more accurately irradiated with a neutron beam.

  The neutron capture therapy system 100 according to the present embodiment includes a position detection system 120 that detects the position of the patient S. The position detection system 120 is configured by a motion capture system. For example, when trying to detect the patient S placed on the mounting table 3 by the CT device, the measurement cannot be performed because the CT device and the neutron irradiation unit 20 interfere with each other. On the other hand, the motion capture system can quantitatively acquire the position of the patient S in the three-dimensional coordinates while avoiding the interference between the devices as described above. Accordingly, the position detection system 120 can quantitatively determine three-dimensionally whether or not the patient S is displaced with respect to the neutron irradiation unit 20. If there is a dislocation, the direction and amount of the displacement Can be obtained quantitatively. As described above, the positional accuracy of the patient S with respect to the neutron beam irradiation unit 20 can be improved.

  The present invention is not limited to the above embodiment.

  For example, in the above embodiment, an optical motion capture system is used, but another type of motion capture system may be used. Depending on the method, the motion capture camera 127 in which the emission unit 123 and the detection unit 122 are integrated may not be used. Further, a motion capture system using electromagnetic waves such as Wi-Fi may be used.

  The first electromagnetic wave emitted by the emitting unit 123 is not limited to infrared light. For example, the emission unit 123 may emit visible light, ultraviolet light, and the like, and may emit ultrasonic waves and the like. Further, the first marker section 124 is not limited to the one that reflects the first electromagnetic wave, and may receive the first electromagnetic wave from the emission section 123 and emit a second electromagnetic wave different from the first electromagnetic wave. The second marker section 125 may also receive the first electromagnetic wave from the emission section 123 and emit a third electromagnetic wave different from the first electromagnetic wave. For example, the emission unit 123 is an external excitation source that generates an electromagnetic field, the marker units 124 and 125 are elements that generate signals by resonating with the electromagnetic field, and the detection unit 122 detects signals from the marker units 124 and 125. Measurement sensor. Further, the emission unit 123 may be a radio wave source that emits radio waves, the marker units 124 and 125 may be reflection members that reflect radio waves, and the detection unit 122 may be a measurement sensor that detects the reflected radio waves.

  In the above embodiment, the center of gravity GP is set as the patient representative point, and the shift of the position of the patient S is determined using the shift of the center of gravity GP from the reference position SP. Alternatively, a reference position is set for the position of the first marker portion 124 itself. However, the method of obtaining the representative point and the method of obtaining the reference position are not particularly limited, and may be appropriately changed.

  3 mounting table, 20 neutron irradiation unit, 23 wall, 31a irradiation hole, 100 neutron capture therapy system, 120 position detection system (position detection unit), 121 arithmetic unit, 123 emission unit, 124 ... first marker part, 125 ... second marker part.

Claims (6)

A neutron capture therapy system for irradiating a patient with a neutron beam,
A mounting table on which the patient is mounted,
A neutron beam irradiation unit that irradiates the neutron beam to the patient mounted on the mounting table,
And a position detection unit that detects the position of the patient,
The position detector,
An emission unit that emits the first electromagnetic wave toward the mounting table;
Attached to the patient placed on the mounting table, reflects the first electromagnetic wave from the emission unit, or receives the first electromagnetic wave and emits a second electromagnetic wave different from the first electromagnetic wave. A first marker section;
A neutron capture therapy system, comprising: a calculation unit that acquires a reflected wave from the first marker unit or the second electromagnetic wave and calculates a position of the first marker unit in three-dimensional coordinates. The position detection unit is attached to at least one of the neutron irradiation unit and the mounting table, and reflects the first electromagnetic wave from the emission unit or receives the first electromagnetic wave and is different from the first electromagnetic wave A second marker section that emits a third electromagnetic wave;
2. The neutron capture according to claim 1, wherein the calculation unit acquires a reflected wave from the second marker unit or the third electromagnetic wave and calculates a position of the second marker unit in three-dimensional coordinates. Therapy system.   3. The calculation unit according to claim 2, wherein the calculation unit calculates a relative positional relationship between the patient and the neutron beam irradiation unit based on a position of the first marker unit and a position of the second marker unit. 4. Neutron capture therapy system. The emission unit emits infrared light as the first electromagnetic wave,
The neutron capture therapy system according to any one of claims 1 to 3, wherein the first marker unit reflects the infrared light.   The said 2nd marker part is an irradiation hole which lets the said neutron beam pass among the said neutron beam irradiation, or at least two are provided in the surface of the wall part in which the said irradiation hole was formed, The Claim 2 or 3 characterized by the above-mentioned. Neutron capture therapy system. A neutron capture therapy system for irradiating a patient with a neutron beam,
A mounting table on which the patient is mounted,
A neutron beam irradiation unit that irradiates the neutron beam to the patient mounted on the mounting table,
And a position detection unit that detects the position of the patient,
The neutron capture therapy system, wherein the position detection unit is configured by a motion capture system.

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