Patent Description:
A stretcher is known that is provided with a patient placement unit on which the patient is positioned, and a conveyance device that conveys the patient placement unit. With respect to the stretcher, there are cases in which, once the patient placement unit on which the patient has been positioned has been conveyed by the conveyance device, the patient placement unit is moved to another location from the conveyance device. Technology is proposed to make this type of movement simple. One example of this is a slide mechanism of the placement unit of the stretcher or the like, as disclosed in Patent Literature <NUM>, for example. According to this technology, after moving the placement unit close to a bed using the conveyance device, the placement unit can be easily move to a center portion of the bed using the slide mechanism.

Further, in Patent Literature <NUM>, a boron neutron capture therapy system used in the treatment of cancer and the like using neutron beams is disclosed. In this boron neutron capture therapy system, a relative positional relationship between a device that irradiates the neutron beams and the body of the patient has an impact on the determination of a section to be treated, and thus, a high degree of positioning accuracy is required. Further, the affected part of the patient that is a treatment target is caused to be as close as possible to an irradiation port of the neutron beams.

However, in the invention disclosed in Patent Literature <NUM>, since the affected part of the patient is caused to be as close as possible to the irradiation port of the neutron beams, there is an issue that contact between the patient and the irradiation port must be prevented.

An object of the present invention is to provide a boron neutron capture therapy system capable of performing positioning with sufficient accuracy at a time of boron neutron capture therapy and capable of preventing contact between a patient and an irradiation port.

A boron neutron capture therapy system according to a first aspect of the present invention is provided with a neutron beam irradiation device inside a room covered with neutron beam shielding, and performs treatment by irradiating neutron beams onto an affected part, into which boron compounds have been injected, of a patient, using the neutron beam irradiation device. The boron neutron capture therapy system includes: a plurality of cameras configured to capture images of the patient, a patient restraint/placement portion that restrains the patient in a state of being placed on the patient restraint/placement portion; a three-dimensional diagnostic device that detects a position of the affected part in the patient; an irradiation table whose position is determined with respect to the neutron beam irradiation device; a position adjustment mechanism that changes a position of the irradiation table with respect to an irradiation port of the neutron beam irradiation device, in relation to each of directions of three axes that are mutually orthogonal; and a control unit that aligns a position of the affected part in the patient detected by the three-dimensional diagnostic device with a position of neutron beams irradiated from the neutron beam irradiation device by changing, using the position adjustment mechanism, a position relating to each of the directions of the three axes of the irradiation table onto which the patient restraint/placement portion has been transferred, and moves the affected part as close as possible to the irradiation port. The control unit three-dimensionally measures a shape of a contour of the body of the patient restrained on the patient restraint/placement portion using images from the plurality of cameras and estimates a spatial position of the contour of the body according to the movement of the irradiation table prior to movement of the irradiation table by simulation. The control unit, using movement of the irradiation table, performs collision avoidance processing that changes the movement of the irradiation table before the patient restrained on the patient restraint/placement portion receives injury by colliding with the irradiation port.

According to the first aspect of the present invention, since the boron neutron capture therapy system is provided with the patient restraint/placement portion that restrains the patient in the state of being placed on the patient restraint/placement portion, the three-dimensional diagnostic device that detects the position of the affected part in the patient, the irradiation table whose position is determined with respect to the neutron beam irradiation device, the position adjustment mechanism that changes the position of the irradiation table with respect to the irradiation port of the neutron beam irradiation device in relation to each of the directions of the three axes that are mutually orthogonal, and the control unit that aligns the position of the affected part in the patient detected by the three-dimensional diagnostic device with the position of the neutron beams irradiated from the neutron beam irradiation device by changing, using the position adjustment mechanism, the position relating to each of the directions of the three axes of the irradiation table onto which the patient restraint/placement portion has been transferred, and that moves the affected part as close as possible to the irradiation port, specific requirements of the boron neutron capture therapy system can be sufficiently fulfilled. Specifically, the boron neutron capture therapy system can be provided that performs position determination with a sufficient degree of accuracy at the time of the boron neutron capture therapy. Further, the control unit, using the movement of the irradiation table, performs collision avoidance processing that changes the movement of the irradiation table before the patient restrained on the patient restraint/placement portion receives injury by colliding with the irradiation port, and thus, collision between the patient and the irradiation port can be avoided.

Below, preferred embodiments of the present invention will be described with reference to the drawings. In the drawings used in the following description, proportions and the like of each of parts are not necessarily accurately drawn.

<FIG> is a diagram schematically showing an example of a configuration of a boron neutron capture therapy system <NUM> (hereinafter referred to simply as a therapy system <NUM>) that is a preferred embodiment of the present invention. As shown in <FIG>, the therapy system <NUM> of the present embodiment is provided with a neutron beam irradiation device <NUM> and an irradiation table <NUM>, inside a room <NUM> that is covered by a neutron beam shielding wall. A three-dimensional diagnostic device <NUM> is provided outside the room <NUM>. A conveyance device <NUM> is provided that can move inside and outside the room <NUM>. Further, the therapy system <NUM> is provided with a camera <NUM>, a camera <NUM>, a camera <NUM>, a camera <NUM>, and a camera <NUM> supported by an aluminum camera frame <NUM>. The cameras <NUM> to <NUM> capture an image, from above, of a patient <NUM> restrained on a patient restraint/placement portion <NUM> to be described later, and are used to acquire three-dimensional data of a contour of a body surface.

The therapy system <NUM> performs therapy by irradiating neutron beams onto an affected part, or a wider area including the affected part, of the patient <NUM> (refer to <FIG> and the like), using the neutron beam irradiation device <NUM>. The neutron beam irradiation device <NUM> is, for example, a known device that irradiates the neutron beams onto the patient <NUM> vertically from above, or in the horizontal direction, or the like. In the treatment using the therapy system <NUM>, for example, boron compounds are injected in advance into the body of the patient <NUM> who is the target of the treatment. After a fixed time period in which the boron accumulates in the affected part, by irradiating the neutron beams from the neutron beam irradiation device <NUM> onto the affected part or a wider area including the affected part, the neutron beams are captured by the boron. The treatment of a tumor and the like in the patient <NUM> is performed as a result of alpha rays and the like that are emitted from the boron that has captured the neutron beams. Specifically, the therapy system <NUM> of the present embodiment performs known boron neutron capture therapy by irradiating the neutron beams onto the affected part of the patient <NUM> using the neutron beam irradiation device <NUM>.

In the treatment using the therapy system <NUM>, before the neutron beams are irradiated onto the patient <NUM> by the neutron beam irradiation device <NUM>, the position of the affected part in the patient <NUM> is detected by the three-dimensional diagnostic device <NUM>. The three-dimensional diagnostic device <NUM> is a device that captures an image of the inside of the body of the patient <NUM>, and, preferably, is a known X-ray computer tomography (CT) device that irradiates X-rays from many directions onto the body of the patient <NUM>, detects the X-rays that have passed through the body using an X-ray detector, performs computer processing on information of the amount of X-rays that have passed through the body, and re-configures the information as a three-dimensional image. The three-dimensional diagnostic device <NUM> may be a known magnetic resonance imaging (MRI) device.

In the present embodiment, the explanation is given of the therapy system <NUM> that is provided with the X-ray CT device as the three-dimensional diagnostic device <NUM>. As shown in <FIG>, the therapy system <NUM> is provided with the patient restraint/placement portion <NUM>. In the treatment of the patient <NUM> using the therapy system <NUM>, the patient <NUM> is placed and restrained on the patient restraint/placement portion <NUM>. As shown in <FIG>, he patient restraint/placement portion <NUM> is a flat plate-shaped member (table top) having a rectangular shape (a long rectangular shape) in a plan view, and edge portions that protrude upward toward the side of a top surface 22a, on which the patient <NUM> is placed, are provided around a peripheral edge portion of the rectangular-shaped member. Specifically, in other words, the patient restraint/placement portion <NUM> is a box-shaped member that does not have a top surface and that is rectangular in a plan view. In the treatment of the patient <NUM> using the therapy system <NUM>, preferably, the patient <NUM> is placed on the patient restraint/placement portion <NUM> in a state of facing upward, and is restrained on the patient restraint/placement portion <NUM> using specific restraints that are not illustrated. The detection of the position of the affected part by the three-dimensional diagnostic device <NUM> shown in <FIG>, the movement of the patient <NUM> between the three-dimensional diagnostic device <NUM> and the neutron beam irradiation device <NUM>, and the irradiation of the neutron beams onto the affected part of the patient <NUM> by the neutron beam irradiation device, and the like are performed on the patient <NUM> who is placed and restrained on the patient restraint/placement portion <NUM> in the above-described manner.

A top portion of the irradiation table <NUM> shown in <FIG>, and <FIG> to <FIG> is provided with a top surface plate 16a. The top surface plate 16a is a flat plate-shaped member that is a rectangular shape (a long rectangular shape) in a plan view, and preferably, is formed in substantially the same shape as the patient restraint/placement portion <NUM> in a plan view. A plurality of protruding portions <NUM> are provided on the surface of the top surface plate 16a. The patient restraint/placement portion <NUM> is placed and restrained on the top surface plate 16a. The top surface plate 16a is configured by a single material or a compound material that is not easily radioactivated, or if radio activated, can suppress that radioactivity to a sufficiently small value. For example, the top surface plate 16a is formed by a resin block (polycarbonate) that is used to cause a metal plate and the patient restraint/placement portion <NUM> to be fitted together. Further, the top surface plate 16a may be configured from a material such as a carbon fiber reinforced plastic (carbon fibers that are cured using a synthetic resin , for example). By configuring the top surface plate 16a using such a material, when the top surface plate 16a is radioactivated by the neutron beams irradiated from the neutron beam irradiation device <NUM>, a maximum exposure (dose equivalent) per hour of an employee is preferably <NUM> mSv or less. In the present embodiment, the employee corresponds to a person engaged in operations inside the room <NUM> when the patient <NUM> is irradiated with the neutron beams by the neutron beam irradiation device <NUM>, and is, for example, a radiological technologist, a doctor, or a nurse. When the patient <NUM> is irradiated by the neutron beams from the neutron beam irradiation device <NUM>, the employee transfers the patient restraint/placement portion <NUM> on which the patient <NUM> is placed from the conveyance device <NUM> to the irradiation table <NUM>, for example. Further, the employee performs various operations relating to the irradiation of the neutron beams in the vicinity of the irradiation table <NUM>. After performing the irradiation of the neutron beams, the employee is engaged in operations to move the patient restraint/placement portion <NUM> on which the patient <NUM> is placed from the irradiation table <NUM> to the conveyance device <NUM> and the like. When assuming the employee as described above, for example, the patient restraint/placement portion <NUM> that is fixed to the top surface plate 16a of the irradiation table <NUM> is positioned within a point-blank range of an irradiation port 14o of the neutron beam irradiation device <NUM>, and a material is chosen such that, when the irradiation from the irradiation port 14o is performed for one hour, the radioactivation of the surface of the top surface plate 16a of the irradiation table <NUM> falls within a range that converts to a <NUM> mSv or less of exposure per hour of the employee at a maximum.

<FIG> is a diagram schematically illustrating a state in which the position of the affected part of the patient <NUM> is being detected by the three-dimensional diagnostic device <NUM>. As shown in <FIG>, the three-dimensional diagnostic device <NUM> is provided with a base <NUM>, a self-propelling image capture unit <NUM> that captures three-dimensional images while moving in one direction (a y axis direction in the example shown in <FIG>) with respect to the base <NUM>, and a bed <NUM> on which the patient <NUM> (the patient restraint/placement portion <NUM> on which the patient <NUM> is restrained) is placed when performing the three-dimensional image capture. The bed <NUM> is preferably a rectangular shape in a plan view, and is provided such that a long direction of the bed <NUM> is the y axis direction shown in <FIG>. The three-dimensional diagnostic device <NUM> is provided with a slide mechanism <NUM> that causes the bed <NUM> to move slidingly with respect to the base <NUM> in the y axis direction shown in <FIG>, and a raising/lowering mechanism <NUM> that raises and lowers the bed <NUM> with respect to the base <NUM> in a z axis direction shown in <FIG>.

When the three-dimensional image capture is performed by the three-dimensional diagnostic device <NUM>, the patient <NUM> lies face up such that a head-to-toe direction is aligned with the movement direction of the self-propelling image capture unit <NUM> (namely, the y axis direction shown in <FIG>). Specifically, the patient restraint/placement portion <NUM> on which the patient <NUM> is placed and restrained is placed on the bed <NUM> such that the head-to-toe direction of the patient <NUM> who is placed and restrained on the patient restraint/placement portion <NUM> in a state of facing upward is aligned with the movement direction of the self-propelling image capture unit <NUM> with respect to the base <NUM>, and the three-dimensional image capture is performed by the self-propelling image capture unit <NUM>.

<FIG> is a perspective view illustrating a configuration of the irradiation table <NUM>. The irradiation table <NUM> is placed in the vicinity of the neutron beam irradiation device <NUM> in the room <NUM>. A position of the patient restraint/placement portion <NUM> that is fixed to the top surface plate 16a is determined with respect to the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM>.

The irradiation table <NUM> functions as a mechanism to determine the position of the patient restraint/placement portion <NUM> fixed to the top surface plate 16a with respect to the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM>, and is provided with a position adjustment mechanism <NUM>, a first angle adjustment mechanism <NUM>, and a second angle adjustment mechanism <NUM>. The position adjustment mechanism <NUM> changes the position of the irradiation table <NUM> with respect to the irradiation port 14o of the neutron beam irradiation device <NUM>, in relation to each of directions of three mutually orthogonal axes (translational axes). In <FIG>, the three axes are indicated by the x, y, and z axes that are mutually orthogonal. The z axis direction corresponds to the vertical direction. The position adjustment mechanism <NUM> is provided with, for example, a y z axis movement arm <NUM> that causes the position of the irradiation table <NUM> with respect to the irradiation port 14o of the neutron beam irradiation device <NUM> to move in the y axis direction and the z axis direction shown in <FIG>, and an x axis movement movable axis <NUM> that causes the position of the irradiation table <NUM> with respect to the neutron beam irradiation port 14o to move in the x axis direction shown in <FIG>. The x axis movement movable axis <NUM> is driven by an X axis motor <NUM> shown in <FIG>. Further, the y z axis movement arm <NUM> is driven by a first YZ axis motor <NUM> and a second YZ axis motor <NUM> shown in <FIG>.

The first angle adjustment mechanism <NUM> changes an angle of the top surface plate 16a of the irradiation table <NUM> with respect to an irradiation direction of the neutron beams, centering on an axis that is parallel to one axis of the three axes. For example, a pitching angle adjustment axis <NUM> is provided that changes the angle of the top surface plate 16a with respect to the irradiation direction of the neutron beams from the neutron beam irradiation port 14o, around an axis that is parallel to the x axis direction shown in <FIG>. The axis that is a center of the rotation by the first angle adjustment mechanism <NUM>, for example, is an axis that is positioned in the center in the lengthwise direction of the top surface plate 16a in a plan view (when seen in the z axis direction) in parallel to the x axis, and is positioned at a predetermined height above the irradiation table <NUM> in the z axis direction. In the present embodiment, the angle adjusted by the first angle adjustment mechanism <NUM> is referred to as a pitching angle. In other words, the top surface plate 16a is configured such that the pitching angle thereof with respect to the irradiation direction of the neutron beams is changed by the top surface plate 16a being rotated around the axis by the first angle adjustment mechanism <NUM>. The pitching angle adjustment axis <NUM> is driven by a pitching angle adjustment motor <NUM> shown in <FIG>.

The second angle adjustment mechanism <NUM> changes an angle of the top surface plate 16a with respect to the irradiation direction of the neutron beams from the neutron beam irradiation port 14o, centering on an axis that is parallel to one axis that is different to the above axis, among the three axes. For example, the angle of the top surface plate 16a with respect to the irradiation direction of the neutron beams from the neutron beam irradiation port 14o is changed around a rotation angle adjustment axis <NUM> that is parallel to the y axis direction shown in <FIG>. In the present embodiment, an angle centering on the rotation angle adjustment axis <NUM> is referred to as a rotation angle. In other words, the top surface plate 16a is configured such that the rotation angle thereof with respect to the irradiation direction of the neutron beams is changed by the top surface plate 16a being rotated around the rotation angle adjustment axis <NUM>. The rotation angle adjustment axis <NUM> is driven by a rotation angle adjustment motor <NUM> shown in <FIG>.

As described above, the irradiation table <NUM> is provided with the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>. Thus, the positions in the x, y, and z axis direction of the top surface plate 16a with respect to the irradiation port 14o of the neutron beam irradiation device <NUM> can all respectively be changed, and at the same time, the pitching angle of the top surface plate 16a around the axis parallel to the x axis, and the rotation angle of the top surface plate 16a around the axis parallel to the y axis can be changed. Preferably, as shown in <FIG>, between a floor plate and the top surface plate 16a, the y z axis movement arm <NUM>, the x axis movement movable axis <NUM>, the pitching adjustment axis <NUM>, and the rotation angle adjustment axis <NUM> are provided, in that order, from the floor surface side toward the top surface plate 16a side. The y z axis movement arm <NUM> and the like are driven, for example, by power generated by an electric motor and the like to be described later, in accordance with commands supplied from a control unit <NUM> to be described later, thus realizing the movement of the top surface plate 16a. The top surface plate 16a of the irradiation table <NUM> is mechanically coupled to the rotation angle adjustment axis <NUM>.

<FIG> are perspective views showing configurations of the irradiation table <NUM>, the conveyance mechanism <NUM>, and the patient restraint/placement portion <NUM>. As shown in <FIG> and so on, the patient restraint/placement portion <NUM> and the top surface plate 16a are provided with engagement structures that are caused to engage with each other in sections that face each other when the patient restraint/placement portion <NUM> is placed on the top surface plate 16a. Specifically, the plurality of protruding portions <NUM>, which protrude to the top surface side from the top surface plate 16a, are provided on the surface of the top surface plate 16a. The protruding portions <NUM> are protruding portions that extend in a short axis direction of the top surface plate 16a (the x axis direction shown in <FIG>). A plurality of groove portions <NUM> are provided in the bottom surface of the patient restraint/placement portion <NUM>, in positions in which they can be engaged with the plurality of protruding portions <NUM>. The groove portions <NUM> are groove portions that extend in the short axis direction of the patient restraint/placement portion <NUM> (the x axis direction shown in <FIG>). When the patient restraint/placement portion <NUM> is placed on the irradiation table <NUM>, the protruding portions <NUM> formed on the irradiation table <NUM> engage with the groove portions <NUM> formed in the patient restraint/placement portion <NUM>, and the position of the patient restraint/placement portion <NUM> with respect to the irradiation table <NUM> is determined. Both the protruding portions <NUM> and the groove portions <NUM> are formed in a longitudinal shape in the short axis direction of the patient restraint/placement portion <NUM> and the irradiation table <NUM>, and thus, at least the movement of the patient restraint/placement portion <NUM> with respect to the top surface plate 16a of the irradiation table <NUM> in the long axis direction (the y axis direction shown in <FIG>) is restricted. As will be described later with reference to <FIG>, the patient restraint/placement portion <NUM> is configured so as to be able to be offset with respect to the irradiation table <NUM> in relation to the y axis direction shown in <FIG>, by displacing the engagement positions of the protruding portions <NUM> and the groove portions <NUM>.

<FIG> shows a state in which the patient restraint/placement portion <NUM> is placed on the conveyance mechanism <NUM>. In the present embodiment, the conveyance mechanism <NUM> conveys the patient restraint/placement portion <NUM>, on which the patient <NUM> is placed and restrained, between the three-dimensional diagnostic device <NUM> and the irradiation table <NUM>. Further, the conveyance mechanism <NUM> functions as a transfer device to transfer the patient restraint/placement portion <NUM> onto the top surface plate 16a. As shown in <FIG> and <FIG>, the conveyance mechanism <NUM> is provided with a holding portion <NUM> and a caster portion <NUM>. The holding portion <NUM> holds the patient restraint/placement portion <NUM> in its placed state, and is fork-shaped such that, after the patient restraint/placement portion <NUM> has been transferred to the three-dimensional diagnostic device <NUM> or the irradiation table <NUM>, the holding portion <NUM> can be pulled out. The caster portion <NUM> is provided with a plurality of wheels and moves the conveyance mechanism <NUM> as a result of the rolling of the wheels on the floor surface. The conveyance mechanism <NUM> may be provided with a raising/lowering mechanism that raises and lowers the patient restraint/placement portion <NUM> placed on the holding portion <NUM>. Using the raising/lowering mechanism provided on the conveyance mechanism <NUM>, the raising/lowering mechanism <NUM> provided on the three-dimensional diagnostic device <NUM> shown in <FIG>, or the position adjustment mechanism <NUM>, the conveyance mechanism <NUM> transfers the patient restraint/placement portion <NUM> on which the patient <NUM> is restrained between the conveyance mechanism <NUM> and the three-dimensional diagnostic device <NUM> or the top surface plate 16a of the irradiation table <NUM>.

Below, with reference to <FIG>, the transfer of the patient restraint/placement portion <NUM> from the conveyance mechanism <NUM> to the top surface plate 16a of the irradiation table <NUM> will be described. In <FIG>, for convenience, the patient restraint/placement portion <NUM> on which the patient <NUM> is not placed is illustrated. In actual treatment using the therapy system <NUM>, the transfer described below is performed while the patient <NUM> is placed and restrained on the patient restraint/placement portion <NUM>. <FIG> shows a state in which the patient restraint/placement portion <NUM> is placed on the conveyance mechanism <NUM>. In this state, the conveyance mechanism <NUM> is moved over the floor surface by the caster portion <NUM>, and the patient restraint/placement portion <NUM> held by the holding portion <NUM> is conveyed.

<FIG> illustrates a state in which, due to the conveyance of the conveyance mechanism <NUM>, the patient restraint/placement portion <NUM> has been moved vertically above the top surface plate 16a of the irradiation table <NUM>. In other words, <FIG> illustrates a state in which the top surface plate 16a of the irradiation table <NUM> is positioned vertically below the patient restraint/placement portion <NUM> held by the holding portion <NUM>. Here, as shown in <FIG>, the position of the patient restraint/placement portion <NUM> with respect to the top surface plate 16a of the irradiation table <NUM> is adjusted in the x axis direction and the y axis direction such that the protruding portions <NUM> formed on the top surface plate 16a of the irradiation table <NUM> and the groove portions <NUM> formed in the bottom surface of the patient restraint/placement portion <NUM> are in mutually corresponding positions. From this state, if the top surface plate 16a of the irradiation table <NUM> is raised in the z axis direction using the position adjustment mechanism <NUM>, the top surface plate 16a lifts up the patient restraint/placement portion <NUM>, and the patient restraint/placement portion <NUM> is separated from the holding portion <NUM> of the conveyance mechanism <NUM>.

<FIG> illustrates a state in which the transfer of the patient restraint/placement portion <NUM> from the conveyance mechanism <NUM> to the irradiation table <NUM> is complete. From the state in which the top surface plate 16a of the irradiation table <NUM> has lifted the patient restraint/placement portion <NUM> and the patient restraint/placement portion <NUM> is separated from the holding portion <NUM> of the conveyance mechanism <NUM>, when the conveyance mechanism <NUM> is moved (retracted) in the x axis direction shown in <FIG>, the holding portion <NUM> is pulled out from below the patient restraint/placement portion <NUM>. At this time, since the protruding portions <NUM> formed on the top surface plate 16a of the irradiation table <NUM>, and the groove portions <NUM> formed in the bottom surface of the patient restraint/placement portion <NUM> are in the mutually corresponding positions, as shown in <FIG>, the protruding portions <NUM> and the groove portions <NUM> are caused to engage with each other.

<FIG> is a perspective view showing a state in which a position of the top surface plate 16a on which the patient restraint/placement portion <NUM> is placed is changed using the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>. <FIG> shows a state, from the state shown in <FIG>, in which the engagement positions of the protruding portions <NUM> and the groove portions <NUM> are displaced, and the patient restraint/placement portion <NUM> is offset in the y axis direction with respect to the top surface plate 16a. In <FIG> and <FIG>, in order to distinguish between the plurality of groove portions <NUM>, they are indicated as groove portions 50a, 50b, 50c, 50d, and 50e. As shown in <FIG> and <FIG>, the patient restraint/placement portion <NUM> placed on the top surface plate 16a is fixed to the top surface plate 16a by a fastening portion <NUM>. The state shown in <FIG> illustrates a state in which the patient restraint/placement portion <NUM> has not been offset with respect to the top surface plate 16a in the y axis direction (y axis offset = <NUM>). When an interval in the y axis direction between the plurality of groove portions <NUM> (namely, an interval between the plurality of protruding portions <NUM>) is <NUM>, when the engagement positions between the protruding portions <NUM> and the groove portions <NUM> are displaced by one (in <FIG>, the protruding portion <NUM> that was engaged with the groove portion 50c is engaged with the groove portion 50d, for example), the patient restraint/placement portion <NUM> is offset (the position is changed in the y axis direction) by <NUM> with respect to the top surface plate 16a.

In <FIG> and <FIG>, a center position of the neutron beam irradiation port 14o (refer to <FIG>) of the neutron beam irradiation device <NUM> is denoted by Cir. When the patient restraint/placement portion <NUM> is offset with respect to the top surface plate 16a, the center position of the neutron beam irradiation port 14o in the patient restraint/placement portion <NUM> moves in the y axis direction. For example, in the state shown in <FIG>, the center position Cir of the neutron beam irradiation port 14o faces a position between the groove portions 50b and 50c. In the state in which, from this state, the engagement positions of the protruding portions <NUM> and the groove portions <NUM> has been displaced by one (refer to <FIG>), the center position Cir of the neutron beam irradiation port 14o faces a position between the groove portions 50c and 50d. More specifically, when the patient restraint/placement portion <NUM> is offset by <NUM> with respect to the top surface plate 16a, the center position Cir of the neutron beam irradiation port 14o with respect to the patient restraint/placement portion <NUM> moves by <NUM> in the opposite direction, in the y axis direction. In other words, the center position Cir of the neutron beam irradiation port 14o with respect to the patient <NUM> placed and restrained on the patient restraint/placement portion <NUM> moves in the y axis direction. In this way, by displacing the engagement positions between the protruding portions <NUM> and the groove portions <NUM>, the center position Cir of the neutron beam irradiation port 14o with respect to the patient <NUM> can be adjusted while the patient <NUM> remains restrained in the state of being placed on the patient restraint/placement portion <NUM>.

As shown in <FIG>, the therapy system <NUM> is provided with the control unit <NUM>. Next, an example of an electrical configuration of the control unit <NUM> will be described with reference to <FIG>. The control unit <NUM> is provided with a CPU <NUM>, a ROM <NUM>, a RAM <NUM>, a non-volatile memory <NUM>, and a position adjustment portion <NUM>. The CPU <NUM> executes various controls relating to the therapy system <NUM> by performing signal processing in accordance with a program stored in advance in the ROM <NUM>, while using temporary storage functions of the RAM <NUM>. As a result, the CPU <NUM> of the control unit <NUM> controls the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM> of the irradiation table <NUM>. Further, the CPU <NUM> receives, from the three-dimensional diagnostic device <NUM> and treatment planning software, information about the position and an attitude angle of the tumor. In control terms, the CPU <NUM> is not combined with the neutron beam irradiation device <NUM>. However, using commands of a surgeon, the CPU <NUM> of the control unit <NUM>, and a CPU (not illustrated) of a control portion of the neutron beam irradiation device <NUM> have mutually coordinated timings. The ROM <NUM> stores an operating system, various programs, and various data. The RAM <NUM> temporarily stores various data. The non-volatile memory <NUM> stores and holds various data.

An X axis motor control portion <NUM>, a first YZ axis motor control portion <NUM>, a second YX axis motor control portion <NUM>, a pitching angle adjustment motor control portion <NUM>, and a rotation angle adjustment motor control portion <NUM> are provided in the position adjustment portion <NUM>. The X axis motor control portion <NUM> controls the X axis motor <NUM>. The first YZ axis motor control portion <NUM> controls the first YZ axis motor <NUM>. The second YZ axis motor control portion <NUM> controls the second YZ axis motor <NUM>. The pitching angle adjustment motor control portion <NUM> controls the pitching angle adjustment motor <NUM>. The rotation angle adjustment motor control portion <NUM> controls the rotation angle adjustment motor <NUM>. The CPU <NUM> controls each of the control portions of the position adjustment portion <NUM>. Thus, each of the motors are controlled by commands from the CPU <NUM>, and the movement of the position in the x, y, and z axis directions, and the changes in the pitching angle and the rotation angle of the top surface plate 16a are controlled so as to be movable in five axis directions. Further, an output of the cameras <NUM> to <NUM> is input to the CPU <NUM>. In addition, a handy terminal <NUM> is connected to the control unit <NUM>, and an output of the handy terminal <NUM> is input to the CPU <NUM>. The handy terminal <NUM> is provided with keys, a display portion and the like that are not illustrated, and can be used to input commands to control the position adjustment portion <NUM>.

Further, the handy terminal <NUM> can be mounted on and removed from the control unit <NUM>, and a configuration is adopted in which, at the time of the irradiation of the neutron beams by the neutron beam irradiation device <NUM>, the handy terminal <NUM> is removed and carried out from the room <NUM>. In addition, the CPU <NUM> of the control unit <NUM> controls operations of the neutron beam irradiation device <NUM> and operations of the three-dimensional diagnostic device <NUM>. The CPU <NUM> executes control to change the position of the top surface plate 16a with respect to the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM>, using at least one of the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>. Specifically, using the position adjustment mechanism <NUM>, the CPU <NUM> performs control to change the position, in each of the directions of the three axes (the x, y, and z axes shown in <FIG> and the like), of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred. Further, using the pitching angle adjustment axis <NUM>, the CPU <NUM> performs control to change the pitching angle of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred. In addition, using the rotation angle adjustment axis <NUM>, the CPU <NUM> performs control to change the rotation angle of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred. By the above-described controls, the CPU <NUM> aligns the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> and the position of the neutron beams irradiated by the neutron beam irradiation device <NUM>, and performs control to cause the affected part to come as close as possible to the neutron beam irradiation port 14o.

As shown in <FIG>, the three-dimensional diagnostic device <NUM> is provided with a pair of horizontal direction lasers 64a and 64b, and a vertical direction laser <NUM>, which perform display to verify positions corresponding to a coordinate system relating to the three-dimensional image capture by the three-dimensional diagnostic device <NUM>. The horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> need not necessarily be integrally provided in the three-dimensional diagnostic device <NUM>, and may be provided separately from the three-dimensional diagnostic device <NUM> inside the room in which the three-dimensional diagnostic device <NUM> is installed. The neutron beam irradiation device <NUM> is provided with a pair of horizontal direction lasers 68a and 68b, and a vertical direction laser <NUM>, which perform display to verify positions of the neutron beams irradiated from the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM>. The horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> need not necessarily be integrally provided in the neutron beam irradiation device <NUM>, and may be provided separately from the neutron beam irradiation device <NUM> in the room <NUM> in which the neutron beam irradiation device <NUM> is installed. In the present embodiment, the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> provided in the three-dimensional diagnostic device <NUM>, and the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> provided in the neutron beam irradiation device <NUM> correspond to a position display portion that performs display to verify that the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> is sufficiently aligned with the position of the neutron beams irradiated from the neutron beam irradiation device <NUM>.

The horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> provided in the three-dimensional diagnostic device <NUM> are preferably movable devices whose position can be changed with respect to the bed <NUM> (the patient <NUM>), and the position thereof is controlled by a control device, such as the control unit <NUM>. Preferably, as shown in <FIG> to be described later, as well as the positions in the vertical direction (the positions in the z axis direction) of the horizontal direction lasers 64a and 64b being changed, the position in the horizontal direction (the position in the x axis direction) of the vertical direction laser <NUM> is changed.

<FIG> is a diagram illustrating an image corresponding to one cross-section in the three-dimensional image captured by the three-dimensional diagnostic device <NUM>. In <FIG>, display positions by the position display portion are also illustrated on the captured image of the body of the patient <NUM>. When the three-dimensional image of the patient <NUM> is captured by the three-dimensional diagnostic device <NUM>, the pair of horizontal direction lasers 64a and 64b and the vertical direction laser <NUM> irradiate laser light onto the body of the patient <NUM>, and thus cause a position corresponding to the coordinate system relating to the capture of the three-dimensional image to be displayed. In <FIG>, a display by the horizontal direction laser 64a is shown by a position 72a, a display by the horizontal direction laser 64b is shown by a position 72b, and a display by the vertical direction laser <NUM> is shown by a position <NUM>, respectively. When the three-dimensional image is captured by the three-dimensional diagnostic device <NUM>, the positions 72a, 72b, and <NUM> displayed on the body of the patient <NUM> by the pair of horizontal direction lasers 64a and 64b and the vertical direction laser <NUM> correspond to an origin point Oct (a CT origin point, for example) relating to the image capture of the three-dimensional diagnostic device <NUM>. In <FIG>, the coordinate system relating to the detection is shown using lines of alternate long and short dashes. For example, an intersection point between a straight line joining the display positions 72a and 72b by the pair of horizontal direction lasers 64a and 64b, and a straight line that is a straight line perpendicular to the above straight line and that passes through the display position <NUM> by the vertical direction laser <NUM> corresponds to the origin point Oct relating to the image capture by the three-dimensional diagnostic device <NUM>.

In the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, when the affected part of the patient <NUM> is detected, an irradiation area can be set over which to perform the treatment on the affected part. Specifically, a treatment plan by the neutron beam irradiation device <NUM> can be devised in accordance with the detected affected part. In the treatment plan, the irradiation positions and the irradiation directions of the neutron beams irradiated from the neutron beam irradiation port 14o with respect to the patient <NUM> are determined. As described above, although the neutron beam irradiation device <NUM> is preferably a device that irradiates the neutron beams onto the patient <NUM> from vertically above, the neutron beam irradiation device <NUM> can change the irradiation position and the irradiation direction of the neutron beams irradiated from the neutron beam irradiation device <NUM> by changing the position, the angle and the like of the patient <NUM> with respect to the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM>.

In <FIG>, as well as showing a tumor central position Cca using a star symbol in the three-dimensional image, with respect to the positions of the neutron beams to be used to effectively perform the treatment at the tumor central position Cca, a display by the horizontal direction laser 68a is shown by a position 76a, a display by the horizontal direction laser 68b is shown by a position 76b, and a display by the vertical direction laser <NUM> is shown by a position <NUM>, respectively. At the time of the irradiation of the neutron beams onto the patient <NUM> by the neutron beam irradiation device <NUM>, the pair of horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> cause the positions of the neutron beams irradiated from the neutron beam irradiation device <NUM> to be displayed by irradiating the laser light onto the body of the patient <NUM>. Specifically, the positions 76a, 76b, and <NUM> displayed on the body of the patient <NUM> by the pair of horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> correspond to the irradiation positions and the irradiation directions with respect to the body of the patient <NUM>, of the neutron beams irradiated from the neutron beam irradiation device <NUM>. Thus, when the treatment plan by the neutron beam irradiation device <NUM> is devised and the irradiation positions and the irradiation directions of the neutron beams irradiated by the neutron beam irradiation device <NUM> are determined on the basis of the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, the positions 76a, 76b, and <NUM> to be displayed on the body of the patient <NUM> by the pair of horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> are established in accordance with the irradiation positions and the irradiation directions of the neutron beams. In <FIG>, the coordinate system relating to the positions of the neutron beams is shown using lines of alternate long and two short dashes.

When the treatment plan by the neutron beam irradiation device <NUM> is devised and the irradiation positions and the irradiation directions of the neutron beams by the neutron beam irradiation device <NUM> are determined on the basis of the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, the control unit <NUM> controls the positions of the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> such that the display positions 72a, 72b and <NUM> by the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> with respect to the patient <NUM> are aligned with the display positions 76a, 76b, and <NUM> of the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> with respect to the patient <NUM> at the time of the treatment using the neutron beam irradiation device <NUM>. Specifically, as well as changing the position of each of the horizontal direction lasers 64a and 64b in the z axis direction, the position of the vertical direction laser <NUM> is changed in the x axis direction, and the irradiation of the laser light is performed. According to this mode, in a diagnosis using the three-dimensional diagnostic device <NUM>, by affixing marks to the display positions of the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> whose positions have been changed in accordance with the position of the detected affected part, at the time of the treatment using the neutron beam irradiation device <NUM>, the positions that should be displayed by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> can be easily indicated.

As described above, the pair of horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> provided in the three-dimensional diagnostic device <NUM>, and the pair of horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> provided in the neutron beam irradiation device <NUM> perform the display in order to verify that an imaging reference point of the three-dimensional image captured by the three-dimensional diagnostic device <NUM> is sufficiently aligned with respect to the coordinate system corresponding to the directions of the three axes of the irradiation table <NUM>. In the treatment of the patient <NUM> using the therapy system <NUM>, at the time of the image capture of the three-dimensional image relating to the patient <NUM> by the three-dimensional diagnostic device <NUM>, preferably, the marks (markings) are affixed using markers or the like, to the positions 72a, 72b, and <NUM> displayed on the body of the patient <NUM> by the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM>. These marks are preferably affixed by a human operation, but may be affixed without requiring human operation, by a method such as applying in advance a material that changes color in response to laser light on the body of the patient <NUM>. As a material of the marks, a material is preferably used by which, on the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, there is a sufficient distinction between a main material of the patient restraint/placement portion <NUM> and the marks.

In the treatment of the patient <NUM> using the therapy system <NUM>, marks are preferably affixed using markers or the like to the positions 76a, 76b, and <NUM> to be displayed on the patient <NUM> by the pair of horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> of the neutron beam irradiation device <NUM>, in correspondence to the position of the affected part detected on the basis of the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, before the irradiation of the neutron beams by the neutron beam irradiation device <NUM>. The material of the marks may be the same material as the marks relating to the diagnosis by the three-dimensional diagnostic device <NUM>, but preferably, a material is used that allows at least sufficient visual distinction between this and the other material.

As shown in <FIG>, the control unit <NUM> is provided with the position adjustment portion <NUM>. The position adjustment portion <NUM> may be provided as a functional portion of the control unit <NUM>, or may be provided as a separate control device to the control unit <NUM>. By causing the position adjustment mechanism <NUM> to change the position in relation to each of the directions of the three axes of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred, on the basis of the marks corresponding to positional coordinates relating to the detection that are affixed to the patient <NUM> when detecting the position of the affected part using the three-dimensional diagnostic device <NUM>, the position adjustment portion <NUM> aligns the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> with the position of the neutron beams irradiated from the neutron beam irradiation device <NUM>.

On the basis of the marks affixed to the positions 76a, 76b, and <NUM> to be displayed on the body of the patient <NUM> by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> of the neutron beam irradiation device <NUM>, the position adjustment portion <NUM> performs position adjustment at the time of the actual treatment using the neutron beam irradiation device <NUM> such that the positions displayed on the body of the patient <NUM> by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> are aligned with the positions to which the marks are affixed. Specifically, at least one of the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM> is adjusted such that an error between the positions displayed on the body of the patient <NUM> by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM>, and the positions to which the marks are affixed is within a prescribed permissible range. Specifically, adjustment is performed such that an error of the imaging reference point of the three-dimensional image by the three-dimensional diagnostic device <NUM> corresponding to the coordinate system relating to the directions of the three axes of the irradiation table <NUM> is within a prescribed permissible range. Preferably, the adjustment by the position adjustment portion <NUM> is performed by the human operation while the surgeon visually verifies a displacement between the positions displayed on the body of the patient <NUM> by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM> and the positions to which the marks have been affixed, but the adjustment may be automatically performed by capturing an image the body of the patient <NUM> and causing the positions of the marks in the captured image and the laser light irradiation positions to be aligned.

Below, an example will be described in detail of a specific treatment using the therapy system <NUM>. In the treatment using the therapy system <NUM>, first, the three-dimensional image of the inside of the body of the patient <NUM> is captured by the three-dimensional diagnostic device <NUM>, and the treatment plan is devised on the basis of the three-dimensional image. In the diagnosis by the three-dimensional diagnostic device <NUM>, first, the patient restraint/placement portion <NUM> is placed on the bed <NUM> of the three-dimensional diagnostic device <NUM>. Next, along with the patient <NUM> being caused to lie face up on the patient restraint/placement portion <NUM>, the patient <NUM> is restrained on the patient restraint/placement portion <NUM> using a dedicated restraint. Next, an image capture start position of the three-dimensional diagnostic device <NUM> with respect to the body of the patient <NUM> (the CT origin point, for example) is displayed using the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM>, and the marks (markings) are affixed to the displayed positions 72a, 72b, and <NUM>. Next, a contour of the affected part (the tumor, for example) is extracted from the three-dimensional image captured by the three-dimensional diagnostic device <NUM>, and the positions of the neutron beams relating to the treatment, such as center coordinates of the affected part and the irradiation angle of the neutron beams, are determined. Then, in accordance with the determined positions of the neutron beams, the positions of the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> are changed by the control unit <NUM>. In this way, the tumor central positions 72a, 72b, and <NUM> (namely, the positions 76a, 76b, and <NUM> at the time of the treatment using the neutron beam irradiation device <NUM>) seen from the left-right side surface, which is orthogonal to neutron beam incident positions and irradiation axes on the body surface of the patient <NUM>, are displayed. Marks (markings) are newly affixed to these three locations. Next, positional coordinates (x y z coordinates, for example) of the center (the tumor center, for example) of the affected part on the patient restraint/placement portion <NUM> relating to the diagnosis by the three-dimensional diagnostic device <NUM>, and information relating to the posture of the patient <NUM> (information corresponding to the pitching angle and the rotation angle, for example) are output to the control unit <NUM> (the control system of the irradiation table <NUM>). In the control unit <NUM>, the positional coordinates of the center of the affected part on the patient restraint/placement portion <NUM>, and the information relating to the posture of the patient <NUM> are stored in the non-volatile memory <NUM> (refer to <FIG>).

Subsequent to the diagnosis by the three-dimensional diagnostic device <NUM>, the patient restraint/placement portion <NUM>, on which the patient <NUM> is placed and restrained, is conveyed and transferred by the conveyance device <NUM> from the three-dimensional diagnostic device <NUM> onto the top surface plate 16a of the irradiation table <NUM>, in the state in which the patient <NUM> is restrained on the patient restraint/placement portion <NUM>. First, the position of the bed <NUM> on the three-dimensional diagnostic device <NUM> in the y axis direction and the z axis direction is moved to a position for transfer, using the slide mechanism <NUM> and the raising/lowering mechanism <NUM>. Next, the conveyance device <NUM> is moved, and the fork-shaped holding portion <NUM> is inserted between the groove portions <NUM> of the patient restraint/placement portion <NUM> and the bed <NUM>. Next, the bed <NUM> is lowered in the z axis direction using the raising/lowering mechanism <NUM>, and the patient restraint/placement portion <NUM> is in a state of being held by the holding portion <NUM> of the conveyance device <NUM>. Then, the conveyance device <NUM> on which the patient restraint/placement portion <NUM> is placed is moved into the room <NUM> in which the neutron beam irradiation device <NUM> is installed. Next, coordinate values output in the diagnosis by the three-dimensional diagnostic device <NUM>, and the offset position in the y axis direction of the patient restraint/placement portion <NUM> with respect to the top surface plate 16a are verified by the control unit <NUM>. Next, the patient restraint/placement portion <NUM> held by the holding portion <NUM> is positioned above the top surface plate 16a in accordance with the verified offset position. Next, the top surface plate 16a is raised in the z axis direction by the position adjustment mechanism <NUM>. In this way, the patient restraint/placement portion <NUM> is placed on the top surface plate 16a, and the protruding portions <NUM> and the groove portions <NUM> are in a state of being engaged in the offset position. Then, after the conveyance device <NUM> has been moved and the fork-shaped holding portion <NUM> has been pulled out from underneath the patient restraint/placement portion <NUM>, the conveyance device <NUM> is removed (withdrawn) to the outside of the room <NUM>.

Following the transfer of the patient restraint/placement portion <NUM> to the top surface plate 16a using the conveyance device <NUM>, on the basis of the marks (markings) affixed to the body of the patient <NUM>, and the display positions of the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM>, the positional alignment relating to the irradiation of the neutron beams by the neutron beam irradiation device <NUM> is performed. <FIG> is a diagram schematically showing a state of the positional alignment. First, the top surface plate 16a is moved, using the position adjustment mechanism <NUM> and the like, such that the imaging reference point relating to the image capture by the three-dimensional diagnostic device <NUM> (the CT origin point, for example) is aligned with the intersection point (hereinafter referred to as a laser pointer intersection point) between the straight line joining the display positions of the horizontal lasers 68a and 68b, and the straight line that is the straight line perpendicular to the above straight line and that passes through the display position of the vertical laser <NUM>. Next, a comparison is made of the marks (markings) affixed in accordance with the imaging reference point, and the display positions by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM>, and when there is the positional displacement, the positions are adjusted by the human operation, using the position adjustment portion <NUM>, for example. Then, on the basis of the information relating to the posture of the patient <NUM> output in the diagnosis by the three-dimensional diagnostic device <NUM>, the pitching angle and a rolling angle of the top surface plate 16a with respect to the neutron beam irradiation port 14o are changed, using the first angle adjustment mechanism <NUM> and the second angle adjustment mechanism <NUM>. As a result of the above positional adjustment, the top surface plate 16a is moved such that the center position of the affected part in data output to the control unit <NUM> is aligned with the laser pointer intersection point. Next, a comparison is made of the positions displayed on the body of the patient <NUM> by the horizontal direction lasers 68a and 68b, and the vertical direction laser <NUM>, and the positions of the marks (markings) corresponding to the affected part and affixed to the body of the patient <NUM>, and when there is positional displacement, the surgeon operates the handy terminal <NUM> and performs positional adjustment using the position adjustment portion <NUM>. Specifically, the adjustment is performed using at least one of the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>, such that the error with the positions to which the marks are affixed is within the prescribed permissible range. Preferably, the center (rotational center) of the pitching angle and the rolling angle relating to this positional adjustment are used as the laser pointer intersection point.

Following the positional alignment relating to the irradiation of the neutron beams by the neutron beam irradiation device <NUM>, the irradiation of the neutron beams by the neutron beam irradiation device <NUM>, namely, the boron neutron capture therapy, is performed. First, when the surgeon operates the handy terminal <NUM> and raises the top surface plate 16a in the z axis direction through control of the position adjustment portion <NUM>, the affected part of the patient <NUM> comes as close as possible to the neutron beam irradiation port 14o. Next, the handy terminal <NUM> is removed from the control unit <NUM>, and the surgeon leaves (withdraws) to the outside of the room <NUM> with the handy terminal <NUM>. Next, the irradiation of the neutron beams onto the affected part of the patient <NUM> by the neutron beam irradiation device <NUM> is performed. Then, the conveyance device <NUM> is moved into the room <NUM>, and the top surface plate 16a is returned to the horizontal, using the first angle adjustment mechanism <NUM>, the second angle adjustment mechanism <NUM>, and the like. Next, the conveyance device <NUM> is moved to a position at which the fork-shaped holding portion <NUM> is inserted under the patient restraint/placement portion <NUM>, and the top surface plate 16a is lowered in the z axis direction by the position adjustment mechanism <NUM>. In this way, the patient restraint/placement portion <NUM> enters the state of being held by the holding portion <NUM> of the conveyance device <NUM>. Then, the patient restraint/placement portion <NUM> on which the patient <NUM> is restrained is conveyed out of the room <NUM>.

Below, algorithms controlling the positional alignment relating to the irradiation of the neutron beams by the neutron beam irradiation device <NUM> will be described in detail while referring to Expressions (<NUM>) to (<NUM>) and the like. The following description is merely an example of favorable control, and the control of the similar positional alignment may be achieved using other algorithms. First, as the treatment plan, x y z coordinates of the CT origin point and the tumor center (the center of the affected part) on the patient restraint/placement portion <NUM>, and information relating to a treatment posture are assigned. For example, (Xct, Yct, Zct) is assigned as the coordinates of the CT origin point, (Xiso, Yiso, Ziso) is assigned as the coordinates of the tumor center), P0 is assigned as the pitching angle, R0 is assigned as the rolling angle R0, and <NUM> × S is assigned as the y axis offset amount, and so on.

Next, conversion is performed from a coordinate system relating to the patient restraint/placement portion <NUM> (hereinafter referred to as a top plate coordinate system) to a coordinate system relating to the irradiation table <NUM> (hereinafter referred to as an irradiation table coordinate system). The origin point of the top plate coordinate system as seen from the irradiation table coordinate system is, for example, (-<NUM>, <NUM> × S - <NUM>, <NUM>). Thus, when a parallel translation of the origin point is defined in the following Expression (<NUM>) and a <NUM>-degree rotation around the x axis, with the aim of conversion since the definition of the coordinates is different, is defined in the following Expression (<NUM>), a CT origin point M in the top plate coordinate system is expressed as in the following Expression (<NUM>) in the irradiation table coordinate system. Expression (<NUM>) <MAT> Expression (<NUM>) <MAT> Expression (<NUM>) <MAT>.

Next, the movement of the top surface plate 16a to the position corresponding to the CT origin point is considered. When a height of the top surface plate 16a from the floor surface at the time of irradiation of the neutron beams by the neutron beam irradiation device <NUM> is <NUM>, a laser pointer intersection point L as seen from the irradiation table coordinate system is (<NUM>, <NUM>, <NUM>), for example. When L is defined as in the following Expression (<NUM>), an x y z axis control target value when performing the parallel translation such that the CT origin point M is aligned with the laser pointer intersection point L is expressed by L - M. In the movement of the top surface plate 16a to the position corresponding to the CT origin point, the position of the top surface plate 16a relating to each of the axes is moved to the position corresponding to that value, by the position adjustment mechanism <NUM>. Expression (<NUM>) <MAT>.

Next, the manual positional adjustment of the top surface plate 16a to the position corresponding to the CT origin point is considered. A center of rotation of the rotation angle adjustment axis <NUM> (hereinafter referred to as an R axis) of the top surface plate 16a is assumed to be the same height as the origin point, for example. A center of rotation of the pitching angle adjustment axis <NUM> (hereinafter referred to as a P axis) of the top surface plate 16a is assumed to be <NUM> vertically above the origin point, for example. Here, when C = (<NUM>, <NUM>,<NUM>), the movement relating to each of the axes in the irradiation table coordinate system is defined in the following manner as a homogeneous transformation matrix. Specifically, when the parallel translation is defined in the following Expression (<NUM>), the R axis rotation is defined in the following Expression (<NUM>), and the P axis rotation is defined in the following Expression (<NUM>), in the manual adjustment of the CT origin point, a CT origin point Ma after applying a correction of (X1, Y1, Z1, P1, R1) is expressed in the following Expression (<NUM>). Here, an error (Ma - M) of the x y z coordinates from a planned position of the CT origin point, and the errors P1 and R1 of the angles can be mainly interpreted as errors in pattern recognition of the top plate coordinate system, or a fitting accuracy of the patient restraint/placement portion <NUM> and the top surface plate 16a (the accuracy relating to the engagement between the protruding portions <NUM> and the groove portions <NUM>). Expression (<NUM>) <MAT> Expression (<NUM>) <MAT> Expression <NUM> <MAT> Expression (<NUM>) <MAT>.

Next, the movement of the top surface plate 16a to the position corresponding to the tumor center is considered. When a control axis origin point is (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), a tumor center N as a planned position is expressed by the following Expression (<NUM>), similarly to the CT origin point M. In the manual adjustment, as a result of moving the CT origin point by (X1, Y1, Z1, P1, R1), when the actual tumor center is positioned at the coordinates N in command data, the coordinates N corresponding to the tumor center are once more returned to the coordinates at the time of the irradiation table coordinate system, and coordinates Na of the tumor center are expressed by the following Expression (<NUM>). Next, a posture when aligning the tumor center Na with the laser pointer intersection point L, namely, coordinates Nb after rotation to the pitching angle P0 + P1 and the rotation angle R0 + R1, is expressed by the following Expression (<NUM>). An x y z control target value when performing parallel translation of the tumor center Nb to the laser pointer intersection point L, after the rotation relating to the P axis and the R axis, is L - Nb. Expression (<NUM>) <MAT> Expression (<NUM>) <MAT> Expression (<NUM>) <MAT>.

Next, the manual positional adjustment of the top surface plate 16a to the position corresponding to the tumor center is considered. As a result of the manual adjustment, when correction of (X2, Y2, Z2, P2, R2) has been performed on the coordinates of the tumor center, a tumor center Nc after the manual adjustment is expressed in the following Expression (<NUM>). Here, an error (Nc - Nb) of the x y z coordinates of the tumor center, and errors P2 and R2 of the angles can be mainly interpreted as wobble in the position of the patient <NUM> in terms of a posture change with respect to the P axis and the R axis, and errors due to flexure and the like of the top surface plate 16a. Expression (<NUM>) <MAT>.

In the movement of the top surface plate 16a to the position calculated in the manner described above, first, the top surface plate 16a is raised in the z axis direction by the position adjustment mechanism <NUM>. A control target value relating to the raising in the z axis direction needs to be a height at which the body of the patient <NUM> comes as close as possible to the neutron beam irradiation port 14o, while the body of the patient <NUM> does not come into contact with the neutron beam irradiation port 14o. In concrete terms, when the neutron beam irradiation port 14o is <NUM> from the floor surface, which is z = <NUM> in the irradiation table coordinate system, whichever of the following is lower is set as the control target value:.

After the top surface plate 16a has been moved by the position adjustment mechanism <NUM> in the above-described manner, the manual positional adjustment of the top surface plate 16a is performed using the position adjustment portion <NUM>, and the position of the top surface plate 16a with respect to the neutron beam irradiation port 14o, and the posture of the patient <NUM> restrained on the patient restraint/placement portion <NUM> are finally determined. For example, by the manual operation by the surgeon, the top surface plate 16a is raised as far as a position at which the body of the patient <NUM> comes as close as possible to the neutron beam irradiation port 14o. In addition, the positional adjustment is performed in the three axial directions and in the rotational directions around the P axis and the R axis, and the posture of the patient <NUM> restrained on the patient restraint/placement portion <NUM> is finally determined. As a result of this manual operation, correction of (X3, Y3, Z3, P3, R3) is performed.

In the above-described control, preferably, information relating to the control is stored as a log in a storage portion provided in the control unit <NUM>. For example, data read into a predetermined storage medium, the manual adjustment values (X1, Y1, Z1, P1, R1) of the CT origin point, the manual adjustment values (X2, Y2, Z2, P2, R2) of the tumor center, the final adjustment values (X3, Y3, Z3, P3, R3), and information about a date, time, and the like at which each of the steps of the position determining procedure are performed are stored.

<FIG> is a diagram illustrating a movement speed of each of portions relating to the positional adjustment of the top surface plate 16a, and <FIG> is a diagram illustrating a number of pulses of each of the portions relating to the positional adjustment of the top surface plate 16a, respectively. <FIG> is a diagram illustrating, in the positional adjustment of the top surface plate 16a, z axis coordinates and a z axis direction speed when a step amount in the y and z axis directions is constant. As shown in <FIG>, in the movement in the z axis direction, given the device dimensions of the top surface plate 16a of the above-described embodiment, a raising and lowering speed corresponding to the movement of the y and z axes is approximately <NUM>-fold different between the top and the bottom of a movable range, even when using the same motor rotation speed. During the z axis movement, a ratio of a manner of moving the first YZ axis motor <NUM> and the second YZ axis motor <NUM> (a rotation amount ratio) is constant. This ratio depends on the structure and dimensions of the y z axis movement arm <NUM>. When the y and z axis speeds are constant irrespective of a height in the z axis direction, at the height at which the body of the patient <NUM> is in the vicinity of the laser pointer intersection point (z = <NUM>, for example), the pulse number is set such that these speeds are close to that of the other axes. With respect to the movement in the z axis direction, when the setting of the number of pulses for yz1 and yz2 is set as a ratio of <NUM>:a expressed by integers, a y axis movement amount resulting from an accumulation error is small. For example, yz1:yz2 = <NUM>:<NUM> is an optimum ratio. In the automatic raising and lowering operation in the transfer of the top surface plate 16a and the conveyance device <NUM>, since a movement in the z axis direction is required to be at a relatively slow speed, the speed is assumed to be approximately <NUM>/<NUM> the movement speed in the z axis direction of the other positional adjustments. In this way, as the movement speed and the number of pulses of each of the parts relating to the positional adjustment of the top surface plate 16a, favorable values such as the values shown in <FIG> and <FIG> are set.

Next, operation methods of a first YZ axis arm <NUM> and a second YZ axis arm <NUM> that configure the YZ axis arm <NUM> will be described with reference to <FIG>. In <FIG>, each of the arms is illustrated in a simplified manner using lines. As shown in <FIG>, the first YZ axis arm <NUM> and the second YZ axis arm <NUM> are connected at a separation point 40a by which each of the first YZ axis arm <NUM> and the second YZ axis arm <NUM> are divided at a ratio of q:p. The first YZ axis motor <NUM> controls the first YZ axis arm <NUM>, and the second YZ axis motor <NUM> controls the second YZ axis arm <NUM>. As a basic operation, a method will be described in which a height, namely, h, is raised and lowered without changing a central position of an upper structural portion loaded on a point 41b (x4, h) of an upper end of the first YZ axis arm <NUM> and a point 43b (x3, h) of an upper end of the second YZ axis arm <NUM>.

First, from the scaling law for triangles:
Expression (<NUM>) <MAT> Then, since the x direction coordinates of a center point of a point 41a (x1, <NUM>) and a point 43a (x2, <NUM>) of the lower ends of each of the arms matches a center point of the two upper points: <MAT> Expression (<NUM>)
If x3 and x4 are solved when Expression A and Expression B are simultaneously established, then: <MAT>.

The raising and lowering without changing the center of the upper structure means that on the device structure, h is moved without changing x3. Thus, when movement amounts by the first YZ axis motor <NUM> and the second YZ axis motor <NUM> are Δ1 and Δ2, respectively, this becomes an identical equation in which a numerator of x3 is identically placed as "zero", and thus:
Expression (<NUM>) <MAT> As in the above Expression (<NUM>), by constantly moving Δ1 and Δ2 at the ratio of the above Expression (<NUM>), the center position of the upper structure can be maintained to be the same.

Next, control of a height movement speed will be described. If Pythagoras' theorem is applied to a lower triangle 40b formed by the separation point 40a of the first YZ axis arm <NUM> and the second YZ axis arm <NUM>, the point 41a, and the point 43a, then: <MAT> As in the above equation, <MAT> By assigning <MAT> into the above equation and sorting out, <MAT> As in Law of simi larity, <MAT> <MAT> <MAT>, By differentiating the above h with L, <MAT> By the above calculation, it can be seen that the speed changes significantly depending on L. Further, the change of speed is not determined by positions of x1 and x2, but by a distance between x1 and x2.

According to the present embodiment, since the therapy system <NUM> is provided with the patient restraint/placement portion <NUM> that restrains the patient <NUM> placed thereon, the three-dimensional diagnostic device <NUM> that detects the position of the affected part in the patient <NUM>, the top surface plate 16a whose position is determined with respect to the neutron beam irradiation device <NUM>, the position adjustment mechanism <NUM> that changes the position of the top surface plate 16a with respect to the neutron beam irradiation port 14o of the neutron beam irradiation device <NUM> in the respective directions of the three axes that are orthogonal to each other, and the control unit <NUM>, which aligns the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> with the position of the neutron beams irradiated from the neutron beam irradiation device <NUM>, by using the position adjustment mechanism <NUM> to change the position, in the directions of each of the three axes, of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred, and which also causes the affected part to come as close as possible to the neutron beam irradiation port 14o, demands unique to boron neutron capture therapy can be sufficiently fulfilled. Specifically, the boron neutron capture therapy system <NUM> can be provided that performs position determining with sufficient accuracy at the time of the boron neutron capture therapy.

Since the therapy system <NUM> is provided with the conveyance device <NUM> as a transfer device to transfer the patient restraint/placement portion <NUM> on which the patient <NUM> is placed and restrained between the three-dimensional diagnostic device <NUM> and the top surface plate 16a, sufficiently accurate position determination can be performed as well as achieving the simple transfer at the time of the boron neutron capture therapy.

When detecting the position of the affected part using the three-dimensional diagnostic device <NUM>, since the therapy system <NUM> is provided with the position adjustment portion <NUM> that aligns the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM>, and the position of the neutron beams irradiated by the neutron beam irradiation device <NUM>, by using the position adjustment mechanism <NUM> to change the position relating to the directions of each of the three axes of the top surface plate 16a onto which the patient restraint/placement portion <NUM> has been transferred, on the basis of the marks corresponding to the positional coordinates relating to the detection that are affixed to the patient <NUM> placed and restrained on the patient restraint/placement portion <NUM>, simple and sufficiently accurate position determination can be performed at the time of the boron neutron capture therapy.

Since the therapy system <NUM> is provided with the first angle adjustment mechanism <NUM> that changes the angle of the top surface plate 16a with respect to the irradiation direction of the neutron beams around an axis that is parallel to one of the axes among the three axes, and the second angle adjustment mechanism <NUM> that changes the angle of the top surface plate 16a with respect to the irradiation direction of the neutron beams around an axis that is parallel to a different one of the axes among the three axes, the position determination relating to the boron neutron capture therapy can be performed simply and with a high degree of accuracy.

Since the patient restraint/placement portion <NUM> and the top surface plate 16a are provided with the protruding portions <NUM> and the groove portions <NUM>, as the engagement structure, on sections that are caused to face each other and be engaged with each other when the patient restraint/placement portion <NUM> is transferred onto the top surface plate 16a, the position of the patient restraint/placement portion <NUM> with respect to the top surface plate 16a can be determined easily and with a high degree of accuracy.

The three-dimensional diagnostic device <NUM> is a device that captures an image of the inside of the body of the patient <NUM>, and, as the material of the marks, a material is used that allows sufficient distinction between the main material of the patient restraint/placement portion <NUM> and the marks in the image captured by the three-dimensional diagnostic device <NUM>. Thus, at the time of the boron neutron capture therapy, the position determination can be performed in an easy and practical manner.

As the transfer device, the therapy system <NUM> is provided with the conveyance device <NUM> that conveys the patient restraint/placement portion <NUM> in a state in which the patient restraint/placement portion <NUM> is placed on the conveyance device <NUM>. The conveyance device <NUM> is provided with the holding portion <NUM> that holds the patient restraint/placement portion <NUM> and that can be pulled out after transferring the patient restraint/placement portion <NUM> onto the three-dimensional diagnostic device <NUM> or onto the top surface plate 16a, and the raising/lowering mechanism provided in the conveyance device <NUM>, the raising/lowering mechanism <NUM> provided in the three-dimensional diagnostic device <NUM>, or the position adjustment mechanism <NUM> is used to transfer the patient restraint/placement portion <NUM> on which the patient <NUM> is restrained between the conveyance device <NUM> and the three-dimensional diagnostic device <NUM> or the top surface plate 16a. Thus, the patient restraint/placement portion <NUM> on which the patient <NUM> is restrained can be transferred between the conveyance device <NUM> and the three-dimensional diagnostic device <NUM> or the top surface plate 16a in an easy and practical manner.

The therapy system <NUM> is provided with the horizontal direction lasers 64a and 64b, and the vertical direction laser <NUM> that function as the position display portion and perform the display in order to verify, on the basis of the display by the position display portion, that the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> is sufficiently aligned with respect to the position of the neutron beams irradiated from the neutron beam irradiation device <NUM>, and is provided with the position adjustment portion <NUM> that performs the adjustment using at least one of the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>, such that the error between the position of the affected part of the patient <NUM> detected by the three-dimensional diagnostic device <NUM> and the position of the neutron beams irradiated from the neutron beam irradiation device <NUM> is within the prescribed permissible range. Thus, the position determination relating to the boron neutron capture therapy can be performed in an easy and practical manner.

The position display portion performs the display to verify that the imaging reference point of the image by the three-dimensional diagnostic device <NUM> is sufficiently aligned with respect to the coordinate system corresponding to the directions of the three axes. Since the position adjustment portion <NUM> performs the adjustment, on the basis of the display by the position display portion, such that the error of the imaging reference point of the image by the three-dimensional diagnostic device <NUM> with respect to the coordinate system corresponding to the directions of the three axes of the top surface plate 16a is within the prescribed permissible range. Thus, the position determination relating to the boron neutron capture therapy can be performed in an easy and practical manner.

The top surface plate 16a is configured from the material ensuring that the maximum exposure per hour of the employee is <NUM> mSv or less when the top surface plate 16a is radioactivated by the neutron beams irradiated from the neutron beam irradiation device <NUM>. Thus, as the material of the top surface plate 16a, a material is used that is not easily radioactivated, or if radioactivated, can suppress that radioactivity to a sufficiently small value. As a result, the exposure of the patient <NUM> and medical employees can be suppressed as much as possible.

Next, collision avoidance processing that prevents mistaken contact of the body of the patient <NUM> with the irradiation port 14o will be described. In the collision avoidance processing, the CPU <NUM> calculates a movable range of a trajectory of three-dimensional data of a contour of a surface of the body of the patient <NUM>, using simulation, and software limit processing is performed to change the movement of the top surface plate 16a. Specifically, the collision avoidance processing measures, three-dimensionally, the shape of the contour of the body of the patient <NUM> restrained on the patient restraint/placement portion <NUM>, estimates a spatial position of the contour of the body of the patient <NUM> in accordance with the movement of the irradiation table <NUM>, and performs the collision avoidance processing. If information can be obtained in advance as to the height of the surface of the body of the patient <NUM> from the top surface plate 16a, when the top surface plate 16a is raised in the z axis direction, the moveable range of the top surface plate 16a can be limited so as to prevent mistaken contact of the body surface of the patient <NUM> with the neutron beam irradiation port 14o that is present immediately above the part to be treated, before such contact happens. As means of obtaining the three-dimensional data of the contour of the body surface of the patient <NUM>, the three-dimensional data of the contour of the body surface of the patient <NUM> is obtained using images from the plurality of optical cameras <NUM> to <NUM>, as shown in <FIG>. As an example, the cameras <NUM> to <NUM> are provided on an upper portion of the aluminum camera frame <NUM>. As an example, the five cameras <NUM> to <NUM> disposed in a circular arc at a height of <NUM> from the floor are installed. As an example of the cameras <NUM> to <NUM>, digital single lens reflex cameras can be used. In the collision avoidance processing, the contour of the body surface of the patient <NUM> is calculated by three-dimensionally reconfiguring images captured from a plurality of angles of the patient <NUM> restrained on the patient restraint/placement portion <NUM>, using stereo camera principles.

Next, generation processing of the contour data of the patient <NUM> will be described with reference to the flowchart shown in <FIG>. First, the CPU <NUM> of the control unit <NUM> reads out camera control software stored in the ROM <NUM>, controls the cameras <NUM> to <NUM>, performs image capture seven times while moving the conveyance device <NUM> on which the patient <NUM> is placed in the head to toe direction, and obtains a total of <NUM> high definition images (step S1).

Three-dimensional data of the body of the patient <NUM> is generated by three-dimensionally reconfiguring the <NUM> high definition images captured in the processing at step S1 (step S2). More specifically, the CPU <NUM> of the control unit <NUM> reads out image analysis software stored in the ROM <NUM>, and, on the basis of the <NUM> high definition images obtained in the processing at step S1, performs generation of three-dimensional data by three-dimensionally reconfiguring the contour shape using the image analysis software (step S2). Examples of the image analysis software include Photoscan (registered trademark) made by Agisoft. The three-dimensional data of the patient <NUM> output by Photoscan (registered trademark) is three-dimensional point group data including RGB information in the ply format.

A handle 22b and a handle 22c are provided, respectively, on both the ends, in a Y direction, of the patient restraint/placement portion <NUM> shown in <FIG>. A reference plate <NUM> shown in <FIG> and <FIG> that is rectangular in a plan view is provided on the upper surface of the handle 22b. A reference plate <NUM> that is rectangular in a plan view is also provided on the upper surface of the handle 22c. The reference plate <NUM> is a black and white checkered pattern, and an intersection point of the black and white checkered pattern is a reference point 23a. A range indicated by a circle 23b shown using a dotted line (refer to <FIG> and <FIG>) is an assumed range of the presence of the intersection point. The reference plate <NUM> is also a black and white checkered pattern, and an intersection point of the black and white checkered pattern is a reference point 25a. In processing at step S3, the reference point 23a and the reference point 25a are detected as reference points of the coordinate system of the patient restraint/placement portion <NUM> (step S3).

The CPU <NUM> of the control unit <NUM> reads out image recognition software stored in the ROM <NUM>, and detects the reference point 23a and the reference point 25a of the patient restraint/placement portion <NUM> (step S3). As an example, the following type of processing is performed. A pitch of the reference point 23a and the reference point 25a is <NUM>. It is assumed that positional coordinate information of the plurality of cameras is set in advance in the image analysis software, using the ground control function of Photoscan (registered trademark), and that the reference point 23a is captured while accuracy is always stable at approximately ± <NUM> in the coordinate system of the reconfigured contour data of the patient <NUM>, taking the position coordinate information as a reference. The ground control function is set such that the X, Y coordinates of the reference point 23a are (<NUM>, <NUM>). Based on this assumption, the reference points on the contour data of the patient <NUM> are always within the following X, Y coordinate range:.

Next, the CPU <NUM> takes a simple mean value of the RGB values, in order to determine, using grey scale, the black and white contrast of the checkered pattern of the reference plate <NUM> and the reference plate <NUM>.

Thus, each of point groups of the contour data of the patient <NUM> becomes a set of the values (X, Y, Z, Grey).

Next, the CPU <NUM> extracts, from the contour data of the patient <NUM>, only points that are in a range [ay1] shown in <FIG>. It is necessary for the size and the position of the range [ay1] to have a dimension in the X direction of <NUM> or more, so that even if the position of the reference plate <NUM> is displaced by ± <NUM>, an edge in the Y direction falls within the range [ay <NUM>]. Further, so that extra parts of the image other than the edge in the Y direction are not included in the range [ay1], it is necessary for the range [ay1] to be disposed providing a distance of <NUM> or more from the outer shape of the reference plate <NUM> and from the reference point 23a. In the present embodiment, the range [ay1] is preferably defined in the following coordinate area: <MAT>.

Next, the CPU <NUM> performs an ascending sort of the Y coordinate values of the point group data [ay1] extracted from the contour data. The CPU <NUM> assigns a reference symbol i to the data order (i = <NUM>, <NUM>,. The CPU <NUM> calculates an average value White of the Grey values from the first to the i-th data array. In the same manner, the CPU <NUM> calculates an average value Black of the Grey values from the i+<NUM>-th to the n-th data array. When i is changed from <NUM> to n - <NUM>, the CPU <NUM> determines that there is the edge from black to white at the i-th point at which the difference between White and Black is largest. In this way, a Y coordinate value of a k-th point is used as a Y coordinate aY1 of the edge. Similarly, the CPU <NUM> determines the edge from white to black for a range [ay2] shown in <FIG>, and uses the edge from white to black as a Y coordinate aY2 of the edge. The CPU <NUM> sets an average value of the detected two edges as the Y coordinate of the reference point 23a.

The CPU <NUM> extracts, from the contour data of the patient <NUM>, only points that are in a range [ax1] shown in <FIG>. From the same viewpoint as for the ranges [ay1] and [ay2], it is necessary for the size and the position of the range [axl] to be defined such that even if the position of the reference plate <NUM> is displaced by ± <NUM>, only an edge in the X direction is within the range [axl].

The CPU <NUM> performs an ascending sort of the X coordinate values of the extracted point group data [axl]. In the same manner as for the Y coordinates, the CPU <NUM> detects X coordinates aX1 and aX2 of the edges of two areas [ax1] and [ax2]. The CPU <NUM> sets an average value of the detected two edges as the X coordinate of the reference point 23a. aX = (aXl + aX2)/<NUM>.

Since there is a tendency for a height of the Z coordinates of the reference point 23a to be output slightly differently in a white area and a black area, it is necessary to calculate the average value of the Z coordinates of an area in which the ratio of each of white and black is the same. The average value of the Z coordinates of a point group of the following area [az] is a Z coordinate aZ of a reference point a. [az]: (aX - <NUM>, aY - <NUM>) < (X, Y), < (aX + <NUM>, aY + <NUM>)
aZ = Average (Z coordinates of [az]).

The CPU <NUM> detects the X, Y, and Z coordinate values of the reference point 25a of the reference plate <NUM> in the same manner as for the reference point 23a.

In order to match all the points of the contour data of the patient <NUM> with the irradiation table coordinate system, the CPU <NUM> performs coordinate conversion including rotation/parallel movement/enlargement and reduction, such that the reference point 23a = (<NUM>, -<NUM>, +<NUM>), and the reference point 25a = (<NUM>, +<NUM>, +<NUM>) (step S4). This is described in detail below.

An example of the irradiation table coordinate system is defined as below.

As a design value, the reference point 23a and the reference point 25a shown in <FIG> are separated by <NUM> in the Y direction. When the coordinate value of the reference point 23a detected in the original data of the contour of the patient <NUM> is a = (aX, aY, zZ), and the coordinate value of the reference point 25a is b = (bX, bY, bZ), the CPU <NUM> calculates the distance |b - a | between the reference point 23a and the reference point 25a, and, by multiplying the original coordinate values by (<NUM>/ | b - a |), matches the contour date of the patient <NUM> to the actual patient <NUM>.

The CPU <NUM> calculates a unit vector of the Y axis in the irradiation table coordinate system using Y = (b - a)/ | b - a |.

For the unit vector of the Z axis in the irradiation table coordinate system, the CPU <NUM> uses the least squares method to calculate a regression place surface from the point group data of a periphery of the reference point 23a (aX ± <NUM>, aY ± <NUM>) and a periphery of the reference point 25a (bX ± <NUM>, bY ± <NUM>). Note here that, given a condition that the unit vector Z of the Z axis is orthogonal to the above unit vector Y of the Y axis, an inner product (Y/Z) = <NUM> is added.

The CPU <NUM> calculates the X axis unit vector relating to the irradiation table coordinate system, using an outer product (Y × Z).

Using the unit vectors X, Y, and Z of the irradiation table coordinate system calculated as above, the CPU <NUM> rotates each of points of the contour data. A transformation matrix is performed using the following Expression.

A rotation operation is performed on each of contour points N as a result of the calculation of the above Expression. Each of the contour points after the rotation is expressed by (R * N).

The CPU <NUM> performs parallel translation such that a midpoint between the reference point 23a and the reference point 25a (a + b)/<NUM> after the above rotation conversion is matched up with the irradiation table coordinate system O = (<NUM>, <NUM>, <NUM>). Each of the contour points after the parallel translation is expressed by (R * N - (a + b)/<NUM> + O). By the above-described operation, the contour data of the patient <NUM> obtained from Photoscan (registered trademark) is caused to match the irradiation table coordinate system, and can be used in the determination by collision avoidance means (step S4). By the above-described processing, the patient <NUM> contour data generating processing is performed.

As an example, the irradiation port 14o shown in <FIG> has a cylindrical shape with a diameter of <NUM>, <NUM>, and is suspended such that the bottom surface of the cylindrical shape is at a height of <NUM>, <NUM> from the floor. During use, a lid of the irradiation port 14o attached to the bottom surface is retracted by being swung to the outside of an operation range of the irradiation table. In the irradiation table coordinate system, a space satisfying: <MAT> and <MAT> is a prohibited area. When using the automatic mode operation for the collision determination in actuality, an additional space of <NUM> in the horizontal direction and <NUM> in the vertical direction is secured with respect to the above area, and a space satisfying the following conditional expressions: <MAT> and <MAT> is the prohibited area.

In the above-described embodiment, since the Z origin point in the irradiation table coordinate system is <NUM> from the floor, a height limit of the irradiation table coordinate system is <NUM>. Taking an additional <NUM> allowance from there is the reason for the height limit of <NUM> in the Z axis direction. Thus, Z ≥ <NUM> becomes the height limit. If the irradiation table coordinate system is not used, and the height limit from the floor is simply determined, <NUM> may be subtracted from <NUM>, and the height limit in the Z axis direction may be <NUM>.

Next, irradiation table movement processing, which performs the collision avoidance processing using position estimation of the patient <NUM>, will be described with reference to <FIG>. The CPU <NUM> of the control unit <NUM> reads, from the non-volatile memory <NUM>, target coordinates of an automatic position determining operation (step S <NUM>). The target coordinates of the automatic position determining operation are stored in advance in the non-volatile memory <NUM>. The CPU <NUM> determines whether a value of the Z coordinate of a highest point of the contour patient <NUM>, in the target coordinates read from the non-volatile memory <NUM>, exceeds the height limit (Z ≥ <NUM>) (step S12). When it is determined that the Z coordinate of the highest point of the contour of the patient <NUM> in the target coordinates exceeds the height limit (yes at step S12), the CPU <NUM> decreases the target coordinate of the Z axis by the amount by which the highest point of the contour of the patient <NUM> exceeds the height limit (step S13).

When it is determined that the Z coordinate of the highest point of the contour of the patient <NUM>, of the target coordinates, does not exceed the height limit (no at step S12), the CPU <NUM> divides a movement of the top surface plate 16a from the current coordinates of the top surface plate 16a to the target coordinates read at step S11 (the X axis movement, the Y axis movement, the Z axis movement, the pitching angle rotation, the rolling angle rotation) into <NUM> equal parts, and calculates a trajectory of the contour of the patient <NUM> when the movement advances in each of <NUM> interval (step S14).

The calculation of the trajectory of the contour of the patient <NUM> (step S14) is performed in the following manner. In the irradiation table coordinate system, when coordinates of an N-th trajectory point of the contour data point group of the patient <NUM> are denoted by N, N is as follows: <MAT>.

The positions of the above contour points are calculated when control coordinate values of the irradiation table are (X, Y, Z, P, R). P indicates the pitching angle rotation, and R indicates the rolling angle rotation. First, the parallel translation of the X, Y, and Z axes, and a simultaneous transformation matrix for the pitching rotation and the rolling rotation relating to each of the control coordinate values are defined as follows: <MAT> <MAT> <MAT>.

A contour point N' after the movement (X, Y, Z, P, R) has been performed with respect to the contour point N is expressed as follows: <MAT>.

Namely, N' is expressed as follows: <MAT>.

Next, the CPU <NUM> determines whether a highest reached point of the contour of the patient <NUM>, of all of the trajectories calculated in the processing at step S14, exceeds the height limit (step S16). When it is determined that the highest reached point does not exceed the height limit (no at step S16), the CPU <NUM> performs the movement of the top surface plate 16a toward the target coordinates (step S17). When it is determined that the highest reached point exceeds the height limit (yes at step S16), the CPU <NUM> decreases a drive speed of the Z axis such that the highest point of the contour of the patient <NUM> is below the height limit (step S15). An example of the processing at step S15 is described below.

The CPU <NUM> finds a point for which the value on the Z axis is largest, among the points exceeding the Z axis limit. Next, the CPU <NUM> resets a Z axis speed Vz using the following Expression: <MAT> Next, the CPU <NUM> verifies that the point exceeding the Z axis limit falls within the range of the limit, at the newly set Z axis speed Vz (step S16). When the point exists that does not fall within the limit (yes at step S16), the CPU <NUM> further resets the Z axis speed Vz using the above Expression (step S15), and using that, once more verifies the points exceeding the Z axis limit that have not yet been verified (step S16). Note that the speed for the Z axis is the speed of the second YZ axis motor <NUM>, and is therefore not matched with the speed of the Z axis, and thus, a three-dimensional trace is once more performed for this determination. However, since the speed is definitely changed in the direction of becoming slower, there is no need to re-determine the point once determined to be exceeding the Z axis limit. When the operation at step S17 is complete, the processing ends.

As described above, in the present embodiment, the three-dimensional data of the contour of the patient <NUM> can be easily obtained by three-dimensionally reconfiguring the images from the plurality of optical cameras. Further, the CPU <NUM> of the control unit <NUM> can limit the movable range of the top surface plate 16a by performing the calculation such that the three-dimensional data of the contour of the patient <NUM> does not enter into the prohibited area of the neutron beam irradiation port 14o and the like due to the movement of the top surface plate 16a. Thus, before the irradiation port 14o comes into contact with the body of the patient <NUM>, by the software simulation, the movable range of the top surface plate 16a can be changed in advance such that the three-dimensional data of the contour of the patient <NUM> does not enter into the prohibited area of the irradiation port 14o and the like. As a result, the contact between the patient <NUM> and the irradiation port 14o can be avoided.

For example, in the above-described embodiment, the collision avoidance processing is realized by the simulation of the trajectory of the three-dimensional data of the contour of the surface of the body of the patient <NUM>, but as shown in <FIG> and <FIG>, emergency shutdown processing may be performed using a pressure sensor <NUM>, which is an example of a proximity sensor. Specifically, the contact between the irradiation port 14o and the patient <NUM> may be detected using the pressure sensor <NUM> that physically detects the contact of the neutron beam irradiation port 14o, and the movement of the top surface plate 16a may be stopped as an emergency before an injury is incurred to the patient <NUM>. The following requirements are necessary as specification requirements of the pressure sensor <NUM>. In order to reduce secondary exposure caused by the radioactivation of materials, the main body of the pressure sensor <NUM> is formed of an organic material configured by elements with a low relative atomic mass. In order to avoid defects such as embrittlement, desensitization, electrical failure and the like caused by the neutron beams, a simple structure as possible is adopted. Due to the risks involved in the above two requirements, disposable use is assumed, and manufacturing costs are commensurate with this. Note that the arrangement of the pressure sensor <NUM> is on the surface of the body of the patient <NUM> in the vicinity of the neutron beam irradiation port 14o.

As an example of the pressure sensor <NUM> that satisfies the above-described requirements, a polyolefin piezoelectric film sensor may be used. As shown in <FIG>, the pressure sensor <NUM> is rectangular in a plan view, and a cable extends from one end thereof and can be connected to the control unit <NUM>. As shown by a cross-section in <FIG>, the outer peripheral surface of the pressure sensor <NUM> is covered by an insulating laminate <NUM>, and an anode <NUM> and a cathode <NUM> are provided in the interior of the pressure sensor <NUM>. A film <NUM> made of a high polymer material that is polarized by pressure is sandwiched between the anode <NUM> and the cathode <NUM>. An example of the high polymer material film <NUM> is a polyolefin piezoelectric film. The pressure sensor <NUM> has an extremely simple structure in which the high polymer material film <NUM> that is polarized by pressure is sandwiched between metallic foil that forms electrodes (the anode <NUM> and the cathode <NUM>), and thus, a high degree of freedom is obtained with respect to the dimensions and the shape of the sensor. As a feature of a signal output of this pressure sensor <NUM>, when the pressure applied to the sensor surface changes, a positive voltage is generated during compression, and a negative voltage is generated during release. If there is no change in the pressure applied to this voltage, since the voltage is attenuated by a time constant within one second, the pressure change resulting from contact can be detected regardless of the shape of the pressure sensor <NUM>, which is adhered so as to follow the body of the patient.

As the emergency stop processing of the top surface plate 16a, by calculating an integrated value of the voltage within the latest second, a contact detection performance that is stable with respect to noise can be obtained. A function is installed that stops the movement when the integrated value exceeds a threshold value, and, in an operation verification test, it was verified that the emergency stop processing was activated at a sufficiently light force (approximately <NUM> × <NUM><NUM>) before an injury was incurred, without reacting when a contact is simply made. The pressure sensor <NUM> using the polyolefin piezoelectric film as described above can reduce the secondary exposure caused by the radioactivation of materials, and, since it has a simple structure, can avoid defects such as embrittlement, desensitization, electrical failure and the like caused by the neutron beams. Further, material costs are cheap, and disposable use is possible. Note that a sensor other than the pressure sensor <NUM> may be used as the proximity sensor. For example, at least one of a high frequency oscillation type sensor, an ultrasonic sensor, a microwave sensor, an infrared sensor, a laser sensor, a photoelectronic sensor, an electrostatic capacitance sensor, and a magnetic sensor may be used. In this case, the approach of the irradiation port 14o can be detected before the contact with the body of the patient <NUM>.

In addition, in the above-described embodiment, the CPU <NUM> of the control unit <NUM> controls the position adjustment portion <NUM>, but a CPU may also be provided in the position adjustment portion <NUM>, and the CPU provided in the position adjustment portion <NUM> may control the position adjustment mechanism <NUM>, the first angle adjustment mechanism <NUM>, and the second angle adjustment mechanism <NUM>. Further, the patient <NUM> contour data generation processing shown in <FIG> may be performed by a computer other than the CPU <NUM> of the control unit <NUM>.

Further, in the above-described embodiment, the patient <NUM> is placed on the patient restraint/placement unit <NUM> in the state of facing upward, but the present invention is not limited to this example, and the patient <NUM> may be placed and restrained on the patient restraint/placement unit <NUM> in a recumbent position on his or her side, or lying face down. In the above-described embodiment, the three-dimensional diagnostic device <NUM> is provided with the self-propelling image capture unit <NUM> that captures the three-dimensional image while being moved in the one direction with respect to the base <NUM>, but a three-dimensional diagnostic device used in the present invention need not necessarily be provided with a self-propelling image capture unit, and various three-dimensional diagnostic devices that detect the position of the affected part in the patient <NUM> can be used. Although not particularly referred to in the above-described embodiment, as the neutron beams used in the boron neutron capture therapy of the present invention, the neutron beams having a specific energy that are safe with respect to living organisms are preferably used. In addition, although not individually exemplified, various modifications can be applied to and realized insofar as they do not depart from the scope of the present invention.

Note that the processing at step S12 to step S15 of the flowchart shown in <FIG> performed by the CPU <NUM> is an example of "collision avoidance processing" of the present invention.

Claim 1:
A boron neutron capture therapy system provided with a neutron beam irradiation device inside a room covered with neutron beam shielding, and configured to perform treatment by irradiating neutron beams onto an affected part, into which boron compounds have been injected, of a patient, using the neutron beam irradiation device, the boron neutron capture therapy system comprising:
a plurality of cameras configured to capture images of the patient;
a patient restraint/placement portion configured to restrain the patient in a state of being placed on the patient restraint/placement portion;
a three-dimensional diagnostic device configured to detect a position of the affected part in the patient;
an irradiation table whose position is determined with respect to the neutron beam irradiation device;
a position adjustment mechanism configured to change a position of the irradiation table with respect to an irradiation port of the neutron beam irradiation device, in relation to each of directions of three axes that are mutually orthogonal; and
a control unit configured to align a position of the affected part in the patient detected by the three-dimensional diagnostic device with a position of neutron beams irradiated from the neutron beam irradiation device by changing, using the position adjustment mechanism, a position relating to each of the directions of the three axes of the irradiation table onto which the patient restraint/placement portion has been transferred, and configured to move the affected part as close as possible to the irradiation port,
wherein
the control unit is configured to three-dimensionally measure a shape of a contour of the body of the patient restrained on the patient restraint/placement portion using images from the plurality of cameras, to estimate a spatial position of the contour of the body according to the movement of the irradiation table prior to movement of the irradiation table by simulation, and to perform collision avoidance processing that changes the movement of the irradiation table before the patient restrained on the patient restraint/placement portion receives injury by colliding with the irradiation port.