JP2005348841A - Diagnostic imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diagnostic imaging apparatus where racks and a bed can be positioned simply, reliably and precisely. <P>SOLUTION: The apparatus comprises: a PET rack 2 which is provided with a photographing means for photographing the PET image of a patient P and arranged movably on a rack guide rail 24; the bed 5 which is arranged movably on a bed guide rail 52 arranged on the extension line of the rack guide rail 24 and where a top plate 51 for placing the patient P can be moved vertically and moved horizontally in a longitudinal direction; and a CT rack 1 which is arranged between the rack guide rail 24 and the bed guide rail 52 and which is provided with a photographing means for photographing the CT image of the patient. The moving distance A of the bed 5 between the position of the bed for PET and the position of the bed for CT is made to be coincident with a distance B between the photographing part of the PET rack 2 and that of the CT rack 1 at a position where the PET rack 2 is stopped near the PET rack 2 stopping surface 15 of the CT rack 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a nuclear medicine diagnostic apparatus such as a PET (Position, Emission, Tomography) apparatus or a SPECT (Single, Photon, Emission, Computed, Tomography) apparatus, an X-ray CT (Computed Tomography) apparatus, or an MRI (onMetRogram) apparatus. -Imaging) The present invention relates to an image diagnosis apparatus that performs image diagnosis by combining apparatuses.

  The image diagnosis can be classified into a morphological image that mainly shows a change in shape and a functional image that sees a change in function. Examples of the functional image diagnostic apparatus for obtaining a functional image include a nuclear medicine diagnostic apparatus such as a PET apparatus and a SPECT apparatus.

  By the way, a PET apparatus or a SPECT apparatus is used for medical diagnosis of tumor, brain dysfunction and the like. A drug that accumulates in a tumor is labeled with a positron or a radioisotope that emits a single photon and then administered to a subject. This drug accumulates at a site such as a tumor of the subject and is released from the body. A photon is imaged with a PET apparatus or SPECT apparatus, and a site such as a tumor appears in the PET image or SPECT image obtained by imaging.

  Next, when a part of a subject diagnosed by a PET image or SPECT image is treated by surgery or chemotherapy, there is little anatomical position information only by taking a functional image of the PET image or SPECT image. In many cases, an anatomical position of a tumor is specified based on position information based on a morphological image such as a CT image or an MRI image obtained by imaging an X-ray CT apparatus, an MRI apparatus, or the like on the same part as the image (for example, Patent Document 1).

  By the way, there is a functional image / morphological image diagnostic apparatus in which a morphological image diagnostic apparatus and a functional image diagnostic apparatus are combined so that both a morphological image and a functional image can be obtained. For example, a PET / CT apparatus combining a PET apparatus and an X-ray CT apparatus mainly includes a PET frame having an imaging unit on the outer periphery of an imaging opening, and an imaging unit outside the imaging opening and the opening. An image processing unit that generates a PET image and a CT image based on data captured by each of the platforms.

  And it is necessary to make the imaging | photography site | part of a subject correspond by imaging | photography on both the PET mount frame and CT mount frame of a PET / CT apparatus. However, when the top plate on which the subject is placed is sent from the bed to the opening of each gantry, the top plate will bend, and the imaging part of the subject will be displaced due to the difference in the deflection of the top plate. In order to avoid this, the bed is moved to the imaging units of the PET frame and the CT frame with the length of the top plate sent out from the bed fixed.

Further, in order to ensure the accuracy of the imaging region of the subject in both imaging on the PET gantry and the CT gantry, the PET gantry and the CT gantry are often fixed. When each gantry is fixed and used, the PET gantry and the CT gantry are separated at the time of maintenance or the like, and the calibration is taken again when the gantry is recombined, and the gantry position is corrected.
JP 2002-214347 A (2nd page, FIG. 1)

  When using only the CT gantry side for imaging in the PET / CT apparatus, and further tilting the CT gantry, use at least one movable gantry to avoid interference between the PET gantry and the CT gantry. It is necessary to move it away.

  For this reason, when diagnosis or treatment is performed with reference to a CT image and a PET image taken by a PET / CT apparatus, it is misdiagnosed or erroneous if the position accuracy due to the mechanical error of the bed or the PET gantry arranged to be movable is poor. There is a risk of leading to treatment.

  By the way, since the gantry and the bed have a considerable weight, it is not possible to control using a high-performance position detection sensor such as a linear scale or an absolute value encoder for positioning that requires accurate position accuracy. However, the system becomes expensive because the control becomes complicated and the number of parts increases.

  The present invention has been made to solve the above-described problems, and provides an image diagnostic apparatus capable of easily, reliably and accurately positioning a diagnostic imaging stand and bed. Objective.

  In order to achieve the above object, an image diagnostic apparatus of the present invention includes a first gantry provided with imaging means for imaging a first image of a subject and movably arranged on a first guide rail. And a bed that is movably disposed on a second guide rail that is disposed on an extension line of the first guide rail, and that can move the top plate on which the subject is placed vertically and move horizontally in the longitudinal direction. And a second gantry provided between the first and second guide rails and provided with imaging means for imaging the second image of the subject, and the first of the bed The moving distance between the imaging position by the gantry and the imaging position by the second gantry is set so that the first gantry imaging unit and the second gantry at the position where the first gantry is stopped close to the second gantry. It is characterized in that the distance is the same as the distance between the photographing parts.

  According to the present invention, since the gantry and the bed are stopped in a state of being close to a predetermined place, the gantry and the bed can be easily and accurately positioned. For this reason, each imaging portion obtained by imaging a plurality of mounts can be accurately associated with each other, so that highly accurate diagnosis and treatment can be performed.

  In the present invention, a PET frame or a SPECT frame can be applied as a functional image photographing frame of the functional image diagnostic apparatus, and a CT frame or an MRI frame can be applied as the morphological image photographing frame of the morphological image diagnostic apparatus. Here, an image diagnostic apparatus applied to a PET / CT apparatus combining a PET gantry and a CT gantry will be described.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing the overall configuration of a PET / CT apparatus according to the present invention. The PET / CT apparatus 100 has a CT gantry 1 having an imaging unit that performs tomography of the subject P with X-rays, and administers a radiopharmaceutical to the subject P, and images a positron emitted from the body of the subject P. Thus, a PET gantry 2 having an imaging unit that performs tomography of the subject P, a top plate 51 on which the subject P is placed, a bed 5 that supports the top plate 51 and moves the top plate 51, and a CT gantry 1 includes a high voltage generation unit 3 that generates a high voltage necessary for X-ray irradiation.

  The PET / CT apparatus 100 includes a mechanism unit 4 that tilts the CT gantry 1, moves the PET gantry 2, moves the bed 5, or moves the top plate 51, and the detectors of the CT gantry 1 and the PET gantry 2. An image generation unit 6 that performs processing of detected and collected data, and a display unit 9 that displays image data processed by the image generation unit 6 are provided.

  Further, the PET / CT apparatus 100 includes a bed position detection unit 7 for positioning the bed 5 when the subject P is set as a desired imaging region by the CT table 1 or the PET table 2, and the PET table 2. A PET position detection unit 8 is provided for performing positioning.

  The PET / CT apparatus 100 controls the operation unit 10 for selecting and inputting various conditions such as subject information, imaging conditions, display conditions, and inputting various commands, and the above units of the PET / CT apparatus 100. The system control unit 11 is controlled.

  The CT gantry 1 includes a substantially cylindrical CT opening 14 into which the subject P on the top plate 51 is sent in the center, an X-ray tube 11 that irradiates the subject P with X-rays, and the subject P. An X-ray detector 12 that is disposed facing the X-ray tube 11 and detects X-rays transmitted through the subject P and converts them into electrical signals, and collects and processes electrical signals output from the X-ray detector 12 And a rotating ring (not shown) that rotatably holds the X-ray tube 11, the detector 14, and the data collecting unit 13 on the outer periphery of the CT opening 14 of the CT mount 1. The CT gantry 1 is held by a holding unit (not shown) so as to be tiltable about a horizontal axis passing through the center of the rotary ring and parallel to the rotary ring surface.

  On the other hand, the PET gantry 2 has a substantially cylindrical PET opening 23 into which the subject P on the top 51 is sent in the center, and a subject administered with radiation arranged in a ring shape on the outer periphery of the PET opening 23. A positron detector 21 that converts a positron emitted from the body of P into an optical signal, further converts the optical signal into an electrical signal and outputs the signal, and a signal processing unit that processes the electrical signal output from the positron detector 21 22 is provided.

  The mechanism unit 4 includes a CT gantry tilt mechanism 41 that tilts the CT gantry 1, a top plate moving mechanism 42 that horizontally moves the couchtop 51 in the vertical direction and the longitudinal direction of the couchtop 51, and the PET gantry 2 as the body of the subject P. A PET frame moving mechanism 43 that moves in the axial direction, a bed moving mechanism 44 that moves the bed 5 toward the opening of the CT frame 1 and the PET frame 2 for imaging by the CT frame 1 or the PET frame 2, and a CT frame tilt A mechanism 41, a couchtop moving mechanism 42, a PET gantry moving mechanism 43, and a couch / topboard / couch mechanism control unit 45 for controlling the couch moving mechanism 44 are provided.

  The high voltage generator 3 includes a high voltage generator 32 that generates a high voltage applied between the anode and the cathode in order to accelerate thermionic electrons generated from the cathode of the X-ray tube 11, and the system controller 11. Is provided with an X-ray control unit 31 that controls X-ray irradiation conditions such as tube current, tube voltage, and irradiation time in the high voltage generator 32.

  The image generation unit 6 processes the data sent from the CT gantry 1 to generate CT image data, and processes the data sent from the PET gantry 2 to generate PET image data. A PET image processing unit 62 that performs the combining process by superimposing the PET image data generated by the PET image processing unit 62 on the CT image data generated by the CT image processing unit 61 and generates PET / CT image data 63.

  The couch position detection unit 7, when performing imaging with the CT gantry 1, uses the CT imaging couch position detector 71 for detecting the couch 5 that moves from the PET gantry imaging position to the CT imaging position, and imaging with the PET gantry 2. When performing the above, a PET imaging bed position detector 72 for detecting the bed 5 moving from the CT imaging position to the PET gantry imaging position is provided.

  Each of the CT imaging bed position detector 71 and the PET imaging bed position detector 72 has a light emitting unit and a light detection unit that detects light emitted from the light emitting unit and converts them into an electrical signal, and is attached to the bed 5. When the cut plate is passed between the light emitting unit and the light detecting unit, the bed 5 is detected at the signal level of the light detecting unit which is lowered when the cut plate of the bed 5 blocks the light of the light emitting unit. It has become.

  The PET position detection unit 8 includes a PET gantry imaging position detector 81 for detecting the PET gantry 2 that moves from the PET gantry standby position of the PET gantry 2 to the PET gantry imaging position in the case of imaging with the PET gantry 2, and a CT gantry. 1 is provided with a PET gantry standby position detector 82 for detecting the PET gantry 2 that moves from the PET gantry imaging position to the PET gantry standby position of the PET gantry 2.

  In the PET gantry imaging position detector 81 and the PET gantry standby position detector 82, a light emitting part and a light detecting part for detecting the light emitted from the light emitting part and converting them into electrical signals are arranged opposite to each other and attached to the PET gantry 2. When the cut plate thus passed passes between the light emitting unit and the light detection unit, the PET frame 2 is detected at the signal level of the light detection unit which is lowered by the cut plate of the PET frame 2 blocking the light of the light emitting unit. Is.

  The signals detected by the bed position detection unit 7 and the PET position detection unit 8 are sent to a gantry / top / bed mechanism control unit 45 configured by a servo amplifier or the like, and the gantry / top / bed mechanism control unit. 45 controls the movement of the couch 5 and the PET gantry 2 by controlling the drive motors of the couch moving mechanism 44 and the PET gantry moving mechanism 43 based on these signals.

  The display unit 9 is a liquid crystal display for displaying the CT image data generated by the CT image processing unit 61, the PET image data generated by the PET image processing unit 61, or the PET / CT image data generated by the image processing unit 63. A monitor such as a CRT is provided.

  The operation unit 10 is an interactive interface including an input device such as a keyboard, a trackball, a joystick, a mouse, a display panel, and various switches, and includes an age, sex, physique, examination site, examination method, past Input of subject information such as diagnosis history, imaging target region (target organ), tilt of CT gantry 1, setting of imaging conditions such as imaging position by moving top plate 51, PET gantry 2, or bed 5, and various commands Make input.

  The system control unit 11 includes a CPU and a storage circuit (not shown), and once stores information such as an operator command signal and imaging conditions supplied from the operation unit 10, CT image data based on these information Control of the entire system, such as generation and display of PET image data or PET / CT image data, and control related to a moving mechanism.

  Next, with reference to FIGS. 2 and 3, the setting of the imaging positions of the gantry and the bed 5 in the imaging of the CT gantry 1 and the PET gantry 2 will be described. FIG. 2 is a diagram showing the positions of the PET frame 2 and the bed 5 when the subject P is imaged using the CT frame 1. The CT gantry 1 is disposed at the position in the figure, and as shown in FIG. 2B, the CT gantry center 16 has a tilt angle of 0 °, and the first tilt 17 and the first tilt 18 can be tilted in the R1 direction. Is retained.

  Further, the CT gantry 1 and the PET gantry 2 at a tilt angle of 0 ° are arranged so that the central axis of the CT opening 14 and the central axis of the PET opening 23 intersect with a horizontal axis 26.

  When imaging is performed using the CT gantry 1, in order to avoid interference with the PET gantry 2 due to the tilt of the CT gantry 1, as shown in FIG. The pedestal 2 is moved to a position (PET gantry standby position) indicated by a solid line in contact with the standby position block 83 for stopping the PET pedestal 2, and the pedestal 5 arranged so as to be movable is used for stopping the pedestal 5 It moves to the position (CT imaging couch position) indicated by the solid line in contact with the CT imaging couch stop block 53.

  In imaging performed using the CT gantry 1 for obtaining CT image data, the CT gantry 1 is tilted in the R1 direction or the top 51 is moved up and down with the couch 5 set to the CT imaging couch position. Alternatively, the imaging region of the subject P is set by horizontal movement of the top 51 in the longitudinal direction.

  Next, the PET gantry 2 and the couch 5 driven by the PET gantry moving mechanism 43 and the couch moving mechanism 44 in FIG. 1 will be described with reference to FIGS. 2 and 3.

  First, the PET gantry 2 driven by the PET gantry moving mechanism 43 will be described. Two gantry guide rails 24 connecting the standby position block 83 and the PET gantry stop surface 15 are arranged on the floor so as to be spaced apart from each other in parallel. The bottom surface of the PET gantry 2 is provided with two movable parts (not shown) that can engage and slide on the gantry guide rail 24, and the PET gantry 2 has a standby position block 83 provided at the end of the gantry guide rail 24. Can be moved horizontally on the guide rail 24 for the gantry between the gantry stand-by position of the PET gantry that is in contact with the CT gantry 2 and the CT gantry 1 that is disposed opposite the PET gantry 2.

  Further, the PET gantry moving mechanism 43 installed at the bottom of the PET gantry 2 is engaged with a screw shaft (not shown) arranged in parallel with the gantry guide rail 24 between the two gantry guide rails 24, It can move in the axial direction.

  That is, the PET gantry moving mechanism 43 has a drive unit such as a motor for rotating a ball screw nut engaged with the screw shaft, and is indicated by a solid line in FIG. 2A by rotating the ball screw nut. Movement between the PET stand standby position of the PET stand 2 and the PET stand photographing position indicated by a broken line is enabled.

  A PET gantry standby position detector 82 is provided on one side of the intermediate part of the gantry guide rail 24 so that the PET gantry 2 stops at the PET gantry standby position during the movement of the PET gantry 2, and this PET gantry standby position detector After passing through 82, the moving speed is reduced. Further, a PET gantry imaging position detector 81 is provided on the other side of the intermediate portion of the gantry guide rail 24 so as to decelerate the PET gantry 2 when it moves to the PET gantry imaging position.

  Next, the bed 5 driven by the bed moving mechanism 44 will be described. Two bed guide rails 52 connecting the CT imaging bed stop block 53 and the PET imaging bed stop block 54 are arranged on the floor in parallel and spaced apart from each other, and the bed guide rail 52 is used for the gantry. It is arranged on an extension line of the guide rail 24.

  The bed 5 has two movable parts (not shown) that are slidable by engaging with two bed guide rails 52 on the bottom surface, and a CT imaging bed stop block 53 provided at one end of the bed guide rail 52; The bed guide rail 52 can be horizontally moved between the PET imaging bed stop blocks 54 provided at the other end of the bed guide rail 52.

  The bed moving mechanism 44 installed at the bottom of the bed 5 is engaged with a screw shaft (not shown) arranged in parallel with the bed guide rail 52 between the two bed guide rails 52, and this screw shaft. It can move in the direction.

  That is, the couch moving mechanism 44 has a drive unit such as a servo motor that rotates a ball screw nut that engages with a screw shaft. By rotating the ball screw nut, the couch 5 is moved to the CT imaging couch stop block 53. And the PET photographing bed stop block 54 can be moved.

  A CT imaging position detector 71 and a PET imaging position detector 72 of the bed 5 are arranged apart from each other in the middle portion of the bed guide rail 52.

  FIGS. 2A and 3 are views showing the positions of the PET gantry 2 and the bed 5 when the CT gantry and the PET gantry 2 take a PET / CT image of the subject P. FIG.

  In imaging performed using the CT gantry 1 to obtain PET / CT image data, the bed 5 is set to the CT imaging gantry position, and the CT gantry 1 is set to the CT gantry center 16 in FIG. The PET gantry 2 is moved to a position (PET gantry imaging position) in contact with the PET gantry stop surface 15 for stopping the PET gantry 2. The PET frame imaging position will be described by taking as an example a position where the PET frame 2 is stopped by contacting the PET frame stop surface 15, but there is no problem in the present invention even if the PET frame 2 is stopped at a slightly separated position. That is, it may be stopped close.

  Further, the top 51 of the bed 5 is moved up and down or horizontally in the longitudinal direction of the top 51, and the imaging part P1 of the subject P in FIG. Set to the first position that coincides with 16 intersections.

  In imaging performed using the PET mount 2 to obtain PET / CT image data, the PET mount 2 is moved in the L1 direction from the state indicated by the solid line in FIG. 2 and set to the PET mount imaging position. The CT mount 1 is held at the CT mount center 16. Further, the couch 5 is moved in the L2 direction from the state indicated by the solid line in FIG. 2 with the top 51 set at the first position, and a position where the couch 5 comes into contact with the couch stop block for PET radiography 54 (for PET radiography). 3, the imaging region P1 of the subject P in FIG. 3 coincides with the intersection of the central axis 26 of the PET opening 23 and the PET gantry center 25, and a PET / CT image with respect to the subject P. The imaging part can be set in the same imaging part P1 as the imaging performed using the CT mount 1 in order to obtain data.

  That is, in the state of setting the first position where the protruding length and the height of the top 51 from the bed 5 are fixed, the bed 5 is moved to the CT imaging bed position in the case of imaging with the CT stand 1. Further, in the case of imaging with the PET gantry 2, the subject P is affected by the deflection of the top plate 51 in the imaging unit of the CT gantry 1 and the imaging unit of the PET gantry 2 by moving the bed 5 to the PET imaging bed position. Therefore, the same imaging region P1 can be set.

  Further, the movement distance A between the CT imaging bed position of the bed 5 and the PET imaging bed position, and the distance B between the imaging unit of the CT frame 1 and the imaging unit of the PET frame 2 at the PET frame imaging position of the PET frame 2 are as follows. By matching, the bed 5 is moved to the CT imaging bed position in the case of imaging by the CT gantry 1, and the bed 5 is moved to the PET imaging bed position in the case of imaging by the PET gantry 2. The imaging part of the subject P in the imaging unit of the gantry 1 and the imaging unit of the PET gantry 2 can be matched.

  Next, in imaging performed using the PET gantry 2 for obtaining PET image data, the CT gantry 1 is held at the CT gantry center 16 and the couch 5 is moved to the PET imaging couch position. The subject P is moved by moving the plate 51 up and down or horizontally in the longitudinal direction of the top plate 51 to set the imaging region of the subject P.

  The imaging performed using the CT gantry 1 and the PET gantry 2 for obtaining the PET / CT image data described with reference to FIGS. 2 and 3 is not limited to the above-described embodiment. For example, first, the PET gantry 2 is used. In order to perform imaging, the bed 5 is moved to the PET imaging bed position, and the PET frame 2 is moved to the PET frame imaging position to perform imaging, and then the bed 5 is moved to the CT imaging bed position to perform CT. You may make it image | photograph with the mount frame 1. FIG.

  FIG. 4 shows a graph 100 of PET gantry movement control in which the PET gantry 2 is controlled when the PET gantry 2 of FIGS. 2 and 3 moves on the gantry guide rail 24. This will be described with reference to FIGS.

  The PET gantry movement control graph 100 includes a PET gantry position axis 101 representing the position of the PET gantry 2 on the gantry guide rail 24 in FIGS. 2 and 3, and a PET gantry speed axis 102 representing the moving speed of the PET gantry 2. 3 shows a relationship 103 between the PET gantry position and speed, which represents the relationship between the position and speed of the PET gantry 2.

  First, when the PET gantry 2 in FIG. 2 moves from the PET gantry standby position in the direction of the PET gantry imaging position indicated by the arrow L1, the PET gantry movement performed by the gantry / top / bed mechanism control unit 45 in FIG. The movement control of the mechanism 43 will be described.

  The positional relationship between the PET gantry position axis 101 of the PET gantry movement control graph 100 and the PET gantry 2 on the gantry guard rail 24 is such that the starting position C of the PET gantry position axis 101 corresponds to the PET gantry standby position, and the first deceleration. The start position E corresponds to the PET gantry imaging position detector 81, and the stop position I corresponds to the PET gantry imaging position.

  Then, by the movement operation input of the PET gantry 2 from the operation unit 10 in FIG. 1, the PET gantry 2 is moved from the PET gantry standby position to the PET gantry imaging position based on the movement control of the gantry / top / bed mechanism control unit 45. Start moving to.

  First, the gantry / top / bed mechanism control unit 45 accelerates the PET gantry 2 from the starting position C of the PET gantry standby position at a predetermined acceleration until it reaches the high speed J, and the constant speed start position at which the high speed J is reached. From D, the PET frame imaging position detector 81 moves at a high speed J to a first deceleration start position E where the PET frame 2 is detected.

  The gantry / top / bed mechanism control unit 45 has a cut plate provided near the gantry guide rail 24 on the bottom surface of the PET gantry 2 between the light emitting unit and the light detecting unit of the PET gantry imaging position detector 81. Based on the photodetection signal of the photodetection unit that decreases by blocking the light emitted by the light emitting unit when passing, deceleration control of the PET gantry 2 is started.

  Next, the gantry / top / bed mechanism control unit 45 decelerates the PET gantry 2 from the first deceleration start position E until the medium speed K is reached at a predetermined deceleration rate, and the first speed that has reached the medium speed K is reached. It moves from the deceleration end position F at the medium speed K, decelerates from the second deceleration start position G after a predetermined time until the low speed L is reached at a predetermined deceleration, and the second deceleration ends when the low speed L is reached. After moving from position H at low speed L, stop at stop position I.

  The stop control of the PET gantry 2 performed by the gantry / top / bed mechanism control unit 45 is performed by driving the PET gantry moving mechanism 43 when the PET gantry 2 comes into contact with the PET gantry stop surface 15 of the CT gantry 2. What is necessary is just to stop the motor by detecting the change in the current flowing through the motor of the part.

  On the other hand, the movement of the PET gantry moving mechanism 43 performed by the gantry / top / bed mechanism controller 45 when the PET gantry 2 in FIG. 3 moves from the PET gantry imaging position toward the PET gantry standby position indicated by the arrow L3. Control will be described.

  The positional relationship between the PET gantry position axis 101 in the PET gantry movement control graph 100 and the PET gantry 2 on the gantry guard rail 24 is such that the starting position C of the PET gantry position axis 101 corresponds to the PET gantry imaging position, and the first deceleration. The start position E corresponds to the PET gantry standby position detector 82, and the stop position I corresponds to the PET gantry standby position.

  The PET gantry standby position detector 82 includes a moving distance a between the PET gantry standby position of the PET gantry 2 and the PET gantry imaging position detector 81 shown in FIG. 3, a PET gantry imaging position, and a PET gantry standby position detector. Since the movement distance b between 82 is the same, the movement control of the PET gantry 2 is performed using the relationship 103 between the PET gantry position and the velocity, similarly to the above-described movement control of the PET gantry 2 in the L1 direction. It can be performed.

  Then, by the movement operation input of the PET gantry 2 from the operation unit 10, the PET gantry 2 moves from the PET gantry imaging position to the PET gantry standby position based on the movement control of the gantry / top / bed mechanism control unit 45. To start.

  Hereinafter, the movement control of the PET gantry 2 to the PET gantry standby position performed by the gantry / top / bed mechanism control unit 45 is the same as the above-described movement control to the PET gantry imaging position, and a description thereof will be omitted.

  FIG. 5 shows a graph 100 of the bed movement control in which the bed 5 is controlled when the bed 5 of FIGS. 2 and 3 moves on the guide rail 52 for the bed. This will be described with reference to FIGS.

  The bed movement control graph 110 includes a bed position axis 111 representing the position of the bed 5 on the guide rail 52 for the bed shown in FIGS. 2 and 3, a bed speed axis 112 representing the moving speed of the bed 5, and the position of the bed 5. A relationship 113 between the bed position and the speed representing the relationship between the speed and the speed is shown.

  First, when the bed 5 in FIG. 2 moves from the CT imaging bed position in the direction of the PET imaging bed position indicated by the arrow L2, the bed movement mechanism performed by the gantry / top / bed mechanism control unit 45 in FIG. The movement control 44 will be described.

  The positional relationship between the bed position axis 111 of the bed movement control graph 110 and the bed 5 on the bed guard rail 52 is such that the starting position M of the bed position axis 111 corresponds to the bed position for CT imaging, and the first deceleration start position O Corresponds to the PET imaging position detector 72, and the stop position S corresponds to the bed position for PET imaging.

  Then, by the movement operation input of the bed 5 from the operation unit 10 in FIG. 1, the bed 5 is changed from the CT imaging bed position to the PET imaging bed position based on the movement control of the gantry / top board / bed mechanism control unit 45. Start moving to.

  First, the gantry / top / bed mechanism control unit 45 accelerates the bed 5 from the starting position M of the CT imaging bed position at a predetermined acceleration until the high speed T is reached, and the constant speed start position at which the high speed T is reached. From N, the PET imaging position detector 72 moves at a high speed T to the first deceleration start position O where the bed 5 is detected.

  In addition, in the gantry / top / bed mechanism control unit 45, the cut plate provided in the vicinity of the bed guide rail 52 on the bottom surface of the bed 5 passes between the light emitting unit and the light detecting unit of the PET imaging position detector 72. At this time, deceleration control of the bed 5 is started on the basis of the light detection signal of the light detection unit that is reduced by blocking the light emitted from the light emitting unit.

  Next, the gantry / top / bed mechanism control unit 45 decelerates the bed 5 from the first deceleration start position O at a predetermined deceleration rate until it reaches the medium speed U, and the first deceleration reaches the medium speed U. The second deceleration end position that has moved from the end position P at the medium speed U, decelerated from the second deceleration start position Q after a predetermined time until reaching the low speed V at a predetermined deceleration, and has reached the low speed V. After moving at a low speed V from R, it stops at the stop position S.

  The stop control of the bed 5 performed by the gantry / top / bed mechanism control unit 45 flows to the motor of the drive unit of the bed moving mechanism 44 when the bed 5 comes into contact with the PET imaging bed stop block 54. The motor is stopped by detecting a current change.

  On the other hand, when the couch 5 in FIG. 3 moves from the couch position for PET imaging in the direction of the couch position for CT imaging indicated by the arrow L4, the couch moving mechanism 44 is controlled by the gantry / top / couch mechanism control unit 45. The movement control will be described.

  The positional relationship between the bed position axis 111 of the bed movement control graph 110 and the bed 5 on the bed guard rail 52 is such that the starting position M of the bed position axis 111 corresponds to the bed position for PET imaging, and the first deceleration start position O Corresponds to the CT imaging position detector 71, and the stop position S corresponds to the bed position for CT imaging.

  The CT imaging position detector 71 includes a movement distance c between the PET imaging bed position and the CT imaging position detector 71 shown in FIG. 3 and a movement distance between the CT imaging bed position and the PET imaging position detector 72. Since b is set to be the same, the movement control of the PET gantry 2 can be performed using the relationship 113 between the bed position and the speed 113, similarly to the movement control of the bed 5 in the L2 direction.

  Based on the movement control input of the bed 5 from the operation unit 10, the bed 5 moves from the PET imaging bed position to the CT imaging bed position based on the movement control of the gantry / top / bed mechanism control unit 45. To start.

  Hereinafter, the movement control of the bed 5 to the CT imaging bed position performed by the gantry / top / bed mechanism control unit 45 is the same as the movement control to the PET imaging bed position described above, and thus the description thereof is omitted.

  According to the embodiment of the present invention described above, the PET gantry and the couch are detected and controlled to decelerate to a predetermined speed, and then the PET gantry and the couch are stopped in contact with a predetermined stop position, so that the accurate and simple Since the gantry and bed can be positioned, the imaging part of the subject can be set accurately, and the PET / CT image data obtained from the imaging of the PET gantry and the CT gantry will be accurate, enabling highly accurate diagnosis and treatment. It can be carried out.

The block diagram which shows the structure of the PET / CT apparatus which concerns on the example of implementation of this invention. The figure which shows the position of a PET frame and a bed in the case of imaging | photography using the CT frame which concerns on the Example of this invention. The figure which shows the position of a PET frame and a bed in the case of imaging | photography using the PET frame which concerns on the Example of this invention. The figure which shows the movement control of the PET mount based on the Example of this invention. The figure which shows the movement control of the bed which concerns on the Example of this invention.

Explanation of symbols

A Distance B Distance P Subject 1 CT mount 2 PET mount 4 Mechanism 5 Sleeper 11 X-ray tube 12 X-ray detector 13 Data collection unit 14 CT opening 15 PET mount stop surface 21 Positron detector 22 Signal processing unit 23 PET Opening 24 Guide rail 42 for pedestal 42 Top plate moving mechanism 43 PET pedestal moving mechanism 44 Bed moving mechanism 45 pedestal / top plate / bed mechanism control unit 51 Top plate 52 guide rail 71 for bed CT bed position detector 72 for CT imaging 72 PET imaging Bed position detector 81 PET frame imaging position detector 82 PET frame standby position detector

Claims (6)

A first gantry comprising imaging means for taking a first image of the subject, and movably disposed on the first guide rail;
A bed that is movably disposed on a second guide rail that is disposed on an extension line of the first guide rail, and that can move vertically and horizontally in the longitudinal direction of the top plate on which the subject is placed;
A second gantry provided between the first and second guide rails and provided with imaging means for imaging a second image of the subject;
The moving distance between the photographing position of the bed by the first gantry and the photographing position of the second gantry is the first gantry at a position where the first cradle is stopped close to the second gantry. Match the distance between the second imaging unit and the second imaging unit,
One of the first and second images is a morphological image and the other is a functional image.   The first gantry and the second gantry each include a PET (Computed Tomography) imaging unit that performs imaging using a positron released from within the subject to which a radiopharmaceutical has been administered, and the other is the subject. 2. The diagnostic imaging apparatus according to claim 1, further comprising an X-ray CT (Computed Tomography) imaging unit that generates an X-ray and performs imaging using the X-ray transmitted through the subject. .   The first gantry is decelerated based on a signal detected by a first gantry photographing position detecting means provided on one side of the first guide rail during the first image photographing, and then the second gantry The diagnostic imaging apparatus according to claim 1, wherein the diagnostic imaging apparatus is in contact with a pedestal and stops.   The bed is decelerated based on a signal detected by a first frame shooting bed position detecting means provided on one side of the second guide rail during the first image shooting, and then the second frame. And the first guide rail stop block provided at one end of the second guide rail between the couch and the bed, and the second guide rail is stopped when the second image is captured. The second frame photographing bed stop block provided at the other end of the second guide rail after decelerating based on the signal detected by the second frame photographing bed position detecting means provided on the other side The diagnostic imaging apparatus according to any one of claims 1 to 3, wherein the diagnostic imaging apparatus is in contact with and stopped.   The first gantry is separated from the second gantry when the second gantry provided with tilting means for tilting the second image photographing means tilts the second image photographing means. The diagnostic imaging apparatus according to any one of claims 1 to 4, wherein the diagnostic imaging apparatus is arranged.   6. The image processing apparatus according to claim 1, further comprising an image processing unit configured to superimpose and process the first image and the second image in the same imaging region as the first image. The diagnostic imaging apparatus according to 1.

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