JP2015213613A - X-ray CT apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray CT apparatus capable of extending a movable range.SOLUTION: In photographing, position information which identifies a current position of a rack device movably arranged in a space such as an examination room and operation room is acquired all the time. A movement control unit, while moving the rack device from a photographing start point to a photographing end point, controls the direction of travel of the rack device so that the direction of travel of the rack device is orthogonal to a photographing cross section by the rack device, on the basis of the acquired position information in the current position.

Description

  Embodiments described herein relate generally to an X-ray CT apparatus.

  In recent years, an X-ray CT (Computed Tomography) apparatus may image a subject placed on a bed or operating table of another medical image diagnostic apparatus. In such a case, the X-ray CT apparatus travels on a rail and moves to a position where a subject placed on a bed or operating table can be imaged.

JP 2009-142332 A

  The problem to be solved by the present invention is to provide an X-ray CT apparatus capable of extending the movable range.

  The X-ray CT apparatus according to the embodiment includes a position information acquisition unit and a movement control unit. The position information acquisition unit acquires position information of the current position of the gantry device. The movement control unit refers to the position information and controls the driving unit to move the gantry device.

FIG. 1 is a perspective view showing an X-ray CT apparatus according to the first embodiment. FIG. 2 is a functional block diagram showing a functional configuration of the X-ray CT apparatus according to the first embodiment. FIG. 3 is a perspective view showing a drive unit according to the first embodiment. FIG. 4 is a diagram for explaining control in the traveling direction by the movement control unit according to the first embodiment. FIG. 5 is a diagram for explaining the control in the traveling direction by the movement control unit according to the first embodiment. FIG. 6 is a diagram for explaining detection of position information by the position information acquisition unit according to the first embodiment. FIG. 7 is a flowchart illustrating a processing procedure during non-shooting by the movement control unit according to the first embodiment. FIG. 8 is a flowchart illustrating a processing procedure at the time of shooting by the movement control unit according to the first embodiment. FIG. 9 is a perspective view showing an X-ray CT apparatus according to the second embodiment. FIG. 10 is a diagram for explaining detection of position information by the X-ray CT apparatus according to the second embodiment.

  Hereinafter, an X-ray CT (Computed Tomography) apparatus according to an embodiment will be described with reference to the drawings. Note that the embodiments are not limited to the following embodiments. In addition, the contents described in one embodiment can be applied to other embodiments in principle as well.

(First embodiment)
FIG. 1 is a perspective view showing an X-ray CT apparatus according to the first embodiment. As shown in FIG. 1, the X-ray CT apparatus according to the first embodiment is movably disposed in a space such as an examination room or an operating room. In order to indicate position information for specifying a position in this space, an orthogonal coordinate system including an X axis, a Y axis, and a Z axis is defined as shown in FIG. That is, the X axis indicates the horizontal direction, the Y axis indicates the vertical direction, and the Z axis indicates the traveling direction of the gantry device 10 during imaging of the subject P placed on the bed apparatus 20.

  Moreover, as shown in FIG. 1, four projectors 2a-2d are installed in the ceiling 1 in the space where an X-ray CT apparatus is arrange | positioned. In addition, when not distinguishing projector 2a-2d, it may describe as projector 2.

  Each projector 2 uses, for example, an LED (Light Emitting Diode) that emits infrared light as a light emitting element. Here, it is assumed that the infrared light emitted by each projector 2 has a unique wavelength for each projector 2. Moreover, the orthogonal coordinate which shows the attachment position of each projector 2 is defined in advance. The X-ray CT apparatus stores the coordinates of each projector 2 and the wavelength in association with each other. Note that the number of projectors installed in the space is not limited to the number illustrated in FIG. 1 and can be arbitrarily changed.

  The X-ray CT apparatus according to the first embodiment includes a gantry device 10 and a console device 30. The bed apparatus 20 is not included in the X-ray CT apparatus. The bed apparatus 20 is an apparatus on which the subject P is placed, and may be a bed of another medical image diagnostic apparatus or an operating table. Here, the bed apparatus 20 is fixed to the floor surface 3, and the coordinates at which the bed apparatus 20 is installed are defined in advance. Note that the X-ray CT apparatus stores the coordinates where the bed apparatus 20 is installed.

  The gantry device 10 irradiates the subject P with X-rays, and collects projection data from X-ray detection data transmitted through the subject P. Further, the gantry device 10 includes drive units 42 a to 42 d that convey the gantry device 10. In FIG. 1, the front left drive unit 42 a and the rear left drive unit 42 c are illustrated by broken lines, and the front right drive unit 42 b and the rear right drive unit 42 d are illustrated by solid lines. Moreover, when not distinguishing the drive parts 42a-42d, it may describe as the drive part 42. FIG.

  Further, as shown in FIG. 1, the gantry device 10 includes a light receiving unit 49 a and a light receiving unit 49 b in the upper part of the gantry device 10. The light receiving unit 49a and the light receiving unit 49b sense light emitted from the projector 2 respectively. The gantry device 10 acquires position information of the gantry device 10 at the current location from the light sensed by the light receiving unit 49a and the light receiving unit 49b. In addition, when not distinguishing the light-receiving part 49a and the light-receiving part 49b, it may describe as the light-receiving part 49.

  Such a gantry device 10 is retracted to, for example, one of the side walls when shooting is not performed. The predetermined position when the gantry device 10 is retracted is referred to as “retracted position”. When photographing, the gantry device 10 travels on the floor surface 3 and moves to the target position in accordance with an instruction from the operator. In addition, the target position said here shows the vicinity of the position which can image | photograph the test object P mounted in the bed apparatus 20. FIG. The coordinates of the target position are also defined in advance. Here, the gantry device 10 senses light emitted from the projector 2, for example, and acquires position information of the gantry device 10 at the current location. Then, the gantry device 10 controls the driving unit 42 with reference to the acquired position information, and moves to the designated target position.

  Subsequently, the gantry device 10 that has moved to the target position is positioned at the imaging start position where the X-ray is actually irradiated and the imaging is started after confirming the imaging range by the projector provided in the gantry device 10. For example, the shooting start position is a shooting start position of a helical scan or a conventional scan. Here, normally, in the helical scan, the rotating frame is continuously rotated while the top plate is moved to take an image. On the other hand, in the conventional scan, imaging is performed by rotating the rotating frame once or continuously while the position of the subject P is fixed. On the other hand, in the present embodiment, in the helical scan, the gantry device 10 may be moved instead of the top plate. Then, the gantry device 10 starts photographing in response to an instruction from the operator. Here, the gantry device 10 senses light emitted from the projector 2, for example, and acquires position information of the gantry device 10 at the current location. The gantry device 10 controls the driving wheel with reference to the position information at the time of photographing, and moves the gantry device 10 from the photographing start point of the helical scan to the photographing end point. During this time, the gantry device 10 irradiates the subject P with X-rays, and collects projection data from X-ray detection data transmitted through the subject P. Here, “at the time of imaging” indicates that the X-ray is being exposed and is moving from the imaging start position to the imaging end position. Further, in the case of “when not photographing”, for example, while the gantry device 10 is retracted to the retracted position, while moving from the retracted position to the target position, or while moving from the target position to the capturing start position, the capturing ends. A time during which the camera moves from the photographing end position to the retracted position later is shown.

  The console device 30 accepts the operation of the X-ray CT apparatus by the operator and reconstructs CT image data from the projection data collected by the gantry device 10. The coordinates where the console device 30 is installed are defined in advance. The X-ray CT apparatus stores the coordinates where the console device 30 is installed.

  FIG. 2 is a functional block diagram showing a functional configuration of the X-ray CT apparatus according to the first embodiment. In the example illustrated in FIG. 2, the gantry device 10 and the console device 30 are illustrated. As shown in FIG. 2, the gantry device 10 includes an X-ray irradiation control unit 11, an X-ray generation device 12, an X-ray detector 13, a collection unit 14, a rotating frame 15, a gantry driving unit 16, The movement control unit 41 includes a driving unit 42a, a driving unit 42b, a driving unit 42c, a driving unit 42d, a position information acquisition unit 48, a light receiving unit 49a, and a light receiving unit 49b. In addition, when not distinguishing the drive parts 42a-42d, it may describe as the drive part 42. FIG. Further, when the light receiving unit 49a and the light receiving unit 49b are not distinguished from each other, the light receiving unit 49 may be described.

  The rotating frame 15 supports the X-ray generator 12 and the X-ray detector 13 so as to be rotatable around the subject P. The rotary frame 15 supports the X-ray generator 12 and the X-ray detector 13 opposite to each other with the subject P interposed therebetween, and rotates at a high speed in a circular orbit around the subject P by a gantry driving unit 16 described later. An annular frame.

  The X-ray generator 12 is an apparatus that generates X-rays and irradiates the subject P with the generated X-rays. The X-ray generator 12 includes an X-ray tube 12a, a wedge 12b, and a collimator 12c. The X-ray detector 13 detects X-rays emitted from the X-ray generator 12 and transmitted through the subject P. Specifically, the X-ray detector 13 detects X-rays that have been irradiated from the X-ray tube 12a and transmitted through the subject P by using two-dimensionally arranged X-ray detection elements.

  The X-ray irradiation control unit 11 is a device that supplies a high voltage to the X-ray tube 12 a as a high voltage generation unit, and the X-ray tube 12 a uses a high voltage supplied from the X-ray irradiation control unit 11. X-rays are generated. The X-ray irradiation control unit 11 adjusts the X-ray dose irradiated to the subject P by adjusting the tube voltage and tube current supplied to the X-ray tube 12a. The X-ray irradiation control unit 11 adjusts the X-ray irradiation range (fan angle and cone angle) by adjusting the aperture of the collimator 12c. Under the control of the X-ray irradiation control unit 11, the X-ray tube 12a continuously exposes X-rays around the subject P for full reconstruction, or exposure that can be reconfigured for half reconstruction. X-rays can be continuously exposed within a range (180 degrees + fan angle).

  The gantry driving unit 16 rotates the rotary frame 15 to rotate the X-ray generator 12 and the X-ray detector 13 on a circular orbit around the subject P.

  The collection unit 14 is a DAS (Data Acquisition System), and collects projection data from X-ray detection data detected by the X-ray detector 13.

  The light receiving unit 49 senses and collects the light emitted from each projector 2 to form a condensing point. For example, the light receiving unit 49 is a position sensor such as a PSD (Position Sensitive Detector), detects the barycentric position of the light receiving intensity at the condensing point, and outputs a signal of a voltage level corresponding to the barycentric position to the position information acquiring unit 48. To do. Note that the light receiving unit 49 identifies the projector 2 that is a light emission source of incident light, for example, based on a difference in wavelength.

  The position information acquisition unit 48 acquires a signal output from each light receiving unit 49 and acquires position information of the current position of the gantry device 10. For example, the position information acquisition unit 48 according to the first embodiment acquires a signal output from each light receiving unit 49 and calculates an incident angle of incident light from each projector 2. Then, the position information acquisition unit 48 performs a triangulation method using the incident angle of each projector 2 and the coordinates of each projector 2 to detect the position of the gantry device 10 for each light receiver 49. Details of the position information acquisition unit 48 will be described later with reference to FIG.

  The drive unit 42 travels on the floor surface 3 by being driven by wheels, and conveys the gantry device 10. Details of the drive unit 42 will be described later with reference to FIGS. 3 to 5.

  The movement control unit 41 controls the traveling direction of the drive unit 42 and the like. For example, at the time of non-photographing, the movement control unit 41 controls the driving wheel with reference to the position information, and moves the gantry device 10 from the retracted position to the target position. Here, the movement control unit 41 moves the gantry device 10 through the shortest route from the retracted position to the target position. For example, the movement control unit 41 controls the driving wheel with reference to the position information during non-shooting, and moves the gantry device 10 from the shooting end position to the retracted position. Here, the movement control unit 41 moves the gantry device 10 through the shortest route from the photographing end position to the retreat position. Further, for example, the movement control unit 41 controls the driving wheel with reference to the position information at the time of shooting, and moves the gantry device 10 from the shooting start point to the shooting end point.

  The console device 30 includes an input device 31, a display device 32, a scan control unit 33, a preprocessing unit 34, a projection data storage unit 35, an image generation unit 36, an image storage unit 37, and a control unit 38. And a position information storage unit 39.

  The input device 31 includes a mouse, a keyboard, buttons, pedals (foot switches), etc., used by an operator of the X-ray CT apparatus for inputting various instructions and various settings, and receives instructions and setting information received from the operator. The data is transferred to the control unit 38.

  The display device 32 is a monitor that is referred to by the operator, displays X-ray CT image data to the operator under the control of the control unit 38, and provides various instructions and various settings from the operator via the input device 31. For example, a GUI (Graphical User Interface) for accepting and the like is displayed. For example, the operator uses the input device 31 to input examination information such as the body position at the time of imaging of the subject P placed on the bed apparatus 20 into the examination information registration GUI.

  The scan control unit 33 controls the operations of the X-ray irradiation control unit 11, the gantry driving unit 16, the collection unit 14, and the movement control unit 41 under the control of the control unit 38 to be described later, so that the projection on the gantry device 10 is performed. Control the data collection process.

  The preprocessing unit 34 performs correction processing such as logarithmic conversion processing, offset correction, sensitivity correction, and beam hardening correction on the projection data generated by the collection unit 14 to generate corrected projection data. To do.

  The projection data storage unit 35 stores the corrected projection data generated by the preprocessing unit 34. The projection data storage unit 35 also stores projection data collected by the collection unit 14.

  The image generation unit 36 is a processing unit that generates various image data using the projection data stored in the projection data storage unit 35. The image storage unit 37 stores various image data generated by the image generation unit 36.

  The control unit 38 performs overall control of the X-ray CT apparatus by controlling operations of the gantry device 10, the couch device 20, and the console device 30. Specifically, the control unit 38 controls the scan performed by the gantry device 10 by controlling the scan control unit 33. The control unit 38 also controls the image reconstruction process and the image generation process in the console device 30 by controlling the preprocessing unit 34 and the image generation unit 36. The control unit 38 controls the display device 32 to display various image data stored in the image storage unit 37.

  The position information storage unit 39 stores position information in a space where the X-ray CT apparatus is arranged. For example, the position information storage unit 39 stores the coordinates where the couch device 20 is arranged, the coordinates where the console device 30 is arranged, the coordinates of the target position, the coordinates of each projector 2, and the like. Note that these pieces of position information are determined in advance by scanning the space.

  The overall configuration of the X-ray CT apparatus according to the first embodiment has been described. With this configuration, the X-ray CT apparatus according to the first embodiment acquires position information of the gantry device 10 at the current location. Then, the X-ray CT apparatus controls the driving wheel with reference to position information at the time of imaging, and moves the gantry device 10 from the imaging start point to the imaging end point. Next, control of the traveling direction of the gantry device 10 will be described in order with reference to FIGS.

  FIG. 3 is a perspective view showing the drive unit 42 according to the first embodiment. The drive unit 42 includes a drive wheel 43, a support unit 44, and a drive motor 45. In FIG. 3, the driving unit 42 a on the left side of the driving unit 42 included in the gantry device 10 is illustrated. The configurations of the other drive units 42b to 42d are the same as the configuration of the drive unit 42a.

  The drive wheel 43 is a tire system and includes a tire member 43a and a wheel member 43b. The drive wheel 43 has a drive motor 45 in or near the wheel member 43b, and rotates by obtaining power from the drive motor 45. FIG. 3 illustrates the case where the drive wheel 43 has the drive motor 45 inside the gantry device 10 and in the vicinity of the wheel member 43b. For example, the drive wheel 43 rotates in the positive direction of the traveling direction by obtaining power from the drive motor 45 that rotates in the direction A in FIG. As a result, the gantry device 10 moves in the forward direction in the traveling direction. Further, for example, the drive wheel 43 rotates in the negative direction of the traveling direction by obtaining power that rotates in the B direction in FIG. 3 from the drive motor 45. As a result, the gantry device 10 moves the traveling direction in the negative direction. Note that the rotation direction and rotation speed of the drive motor 45 are switched according to an instruction from the movement control unit 41.

  A predetermined tread pattern may be engraved on the tire member 43a of the drive wheel 43. Thereby, even if the liquid is sprayed on the floor surface 3, the drive wheel 43 discharges | emits a liquid and makes the contact with the floor surface 3 dense. Thereby, the drive wheel 43 can prevent the slip on the floor surface 3. Further, the tire member 43a of the drive wheel 43 is formed of a rubber material having slip resistance. This rubber material has a dynamic friction coefficient designed in advance. Thereby, the drive wheel 43 can prevent slipping even when, for example, blood of the subject P is spread on the floor surface 3 during the operation.

  The support portion 44 includes a fixed member 44a and a rotating member 44b. The support unit 44 fixes the driving wheel 43 and rotates at the designated angle in accordance with an instruction from the movement control unit 41 to change the traveling direction of the driving wheel 43.

  The fixing member 44 a is connected to the end portions on both sides of the wheel member 43 b of the drive wheel 43. In this manner, the fixing member 44a is connected to the wheel member 43b, so that the support portion 44 and the drive wheel 43 can move in an integrated manner.

  The rotating member 44b rotates according to an instruction from the movement control unit 41. For example, the rotation member 44b rotates around the Y axis to an angle indicated by the movement control unit 41 in response to an instruction from the movement control unit 41. The rotating member 44b can rotate 360 degrees. Here, since the fixing member 44 a fixes the drive wheel 43, the rotation angle of the rotation member 44 b matches the rotation angle of the drive wheel 43. As described above, the rotation direction of the driving wheel 43 can be controlled by the rotation member 44b rotating according to the instruction of the movement control unit 41. In other words, the drive wheel 43 can perform a complicated operation.

  4 and 5 are diagrams for explaining the control of the traveling direction by the movement control unit 41 according to the first embodiment. 4 and 5 show a case where the gantry device 10 is viewed from the ceiling 1 side. 4 and 5, the rotating frame 15 of the gantry device 10 is schematically indicated by a broken line. FIG. 4 shows a case where the position of the driving wheel 43 of the gantry device 10 in the traveling direction is a position parallel to the Z axis. That is, the movement control unit 41 maintains the initial position without rotating the rotating member 44b. In such a case, the gantry device 10 advances to a position parallel to the Z axis by obtaining a driving force.

  Here, for example, when the movement control unit 41 rotates the rotation member 44b of each drive unit 42 by 90 degrees to the left from the initial position, the position in the traveling direction of the drive wheel 43 of the gantry device 10 is shown in FIG. It becomes a state. That is, the position of the driving wheel 43 in the traveling direction is a position parallel to the X axis. In such a case, the gantry device 10 advances to a position parallel to the X axis by obtaining a driving force. In this way, the movement control unit 41 controls the traveling direction of the gantry device 10 by rotating the rotating member 44 b and controlling the position of the driving wheel 43 in the traveling direction.

  Next, the acquisition of the position information of the gantry device 10 by the position information acquisition unit 48 according to the first embodiment will be described with reference to FIG. FIG. 6 is a diagram for explaining detection of position information by the position information acquisition unit 48 according to the first embodiment. In FIG. 6, the figure which looked at the space where the X-ray CT apparatus was installed from the ceiling 1 side is shown. The coordinates of the projectors 2a to 2d shown in FIG. 6 are assumed as follows. For example, the coordinates of the projector 2a are (X2, Z3), the coordinates of the projector 2b are (X1, Z2), the coordinates of the projector 2c are (X2, Z1), and the coordinates of the projector 2d are (X3, Z2).

  For example, the light receiving unit 49a senses and collects light emitted from the projector 2c and the projector 2d to form a condensing point. The light receiving unit 49a detects the barycentric position of the light receiving intensity at the condensing point for the light emitted from the projector 2c, and outputs a signal having a voltage level corresponding to the barycentric position to the position information acquiring unit 48. In addition, the light receiving unit 49a detects the barycentric position of the light receiving intensity at the condensing point for the light emitted from the projector 2d, and outputs a signal having a voltage level corresponding to the barycentric position to the position information acquiring unit 48.

  Similarly, for example, the light receiving unit 49b senses and collects light emitted from the projector 2b and the projector 2c to form a condensing point. The light receiving unit 49b detects the barycentric position of the light receiving intensity at the condensing point for the light emitted from the projector 2b, and outputs a voltage level signal corresponding to the barycentric position to the position information acquiring unit 48. The light receiving unit 49b detects the barycentric position of the light reception intensity at the condensing point for the light emitted from the projector 2c, and outputs a signal having a voltage level corresponding to the barycentric position to the position information acquiring unit 48.

  The position information acquisition unit 48 according to the first embodiment acquires signals output by the light receiving unit 49a and the light receiving unit 49b, and calculates the incident angle of the incident light from the projector 2. For example, the position information acquisition unit 48 calculates the incident angle of the incident light from the projector 2c and the incident angle of the incident light from the projector 2d from the signal output from the light receiving unit 49a. For example, the position information acquisition unit 48 calculates the incident angle of the incident light from the projector 2b and the incident angle of the incident light from the projector 2c from the signal output from the light receiving unit 49b.

  Then, the position information acquisition unit 48 performs a triangulation method using the incident angle of each projector 2 and the coordinates of each projector 2 to detect the position of the gantry device 10 for each light receiver 49. For example, the position information acquisition unit 48 performs a triangulation method using the coordinates of the projector 2c, the incident angle of the incident light from the projector 2c, and the coordinates of the projector 2d and the incident angle of the incident light from the projector 2d. The position information P1 detected by the light receiving unit 49a is detected. Further, for example, the position information acquisition unit 48 performs a triangulation method using the coordinates of the projector 2b, the incident angle of the incident light from the projector 2b, and the coordinates of the projector 2c and the incident angle of the incident light from the projector 2c. The position information P2 detected by the light receiving unit 49b is detected. It should be noted that other known techniques can be substituted for the acquisition of position information.

  FIG. 7 is a flowchart illustrating a processing procedure during non-shooting by the movement control unit 41 according to the first embodiment. FIG. 7 illustrates a case where the gantry device 10 moves to the target position in accordance with the operator's instruction. It is assumed that the target positions are two points Q1 and Q2 represented by XZ coordinates. The distance between the two points Q1 and Q2 is equal to the distance between the two points of the position information P1 detected by the light receiving unit 49a and the position information P2 detected by the light receiving unit 49b.

  As illustrated in FIG. 7, the movement control unit 41 acquires a target position (step S101). For example, when the movement control unit 41 receives an instruction to move to the target position from the operator, the coordinates of the target position stored in the position information storage unit 39 via the scan control unit 33, the coordinates of each projector 2, etc. Position information in a space where the X-ray CT apparatus is arranged is acquired.

  Subsequently, the movement control unit 41 acquires the current position information from the position information acquisition unit 48 (step S102). Here, the movement control unit 41 acquires, as the current position information, position information of two points, position information P1 detected by the light receiving unit 49a and position information P2 detected by the light receiving unit 49b. Then, the movement control unit 41 determines whether or not the target position matches the acquired position information (step S103). Here, the movement control unit 41 determines whether or not the target position matches the acquired position information in consideration of the shooting direction.

  For example, the movement control unit 41 matches the target position and the acquired position information when the target position Q1 matches the acquired position information P1 and the target position Q2 matches the acquired position information P2. Judge that. Further, for example, when the target position Q1 and the acquired position information P1 match, but the target position Q2 and the acquired position information P2 do not match, the movement control unit 41 does not match the target position and the acquired position information. Is determined. Similarly, if the target position Q2 and the acquired position information P2 match, but the target position Q1 and the acquired position information P1 do not match, the movement control unit 41 determines that the target position does not match the acquired position information. judge. Further, for example, the movement control unit 41, when the target position Q1 matches the acquired position information P2, and the target position Q2 matches the acquired position information P1, the target position and the acquired position information Are determined not to match. The movement control unit 41 does not match the target position with the acquired position information even if the target position Q1 does not match the acquired position information P1 and the target position Q2 does not match the acquired position information P2. Is determined.

  Here, when the movement control unit 41 does not determine that the target position matches the acquired position information (No in Step S103), the movement control unit 41 controls the drive motor 45 and the rotation member 44b to control the drive wheel 43. Driven to move a predetermined distance (step S104). The movement control unit 41 proceeds to step S102 after step S104, and repeatedly executes the processing from step S102 to step S104 until the target position matches the acquired position information. On the other hand, if the movement control unit 41 determines that the target position matches the acquired position information (Yes in step S103), the process ends.

  FIG. 8 is a flowchart illustrating a processing procedure at the time of shooting by the movement control unit 41 according to the first embodiment. FIG. 8 shows a processing procedure in the case where the gantry device 10 has moved to the target position and photographing is started in accordance with an instruction from the operator. When the gantry device 10 has moved to the target position, the traveling direction of the gantry device 10 and the imaging cross section by the gantry device 10 are orthogonal to each other.

  As shown in FIG. 8, the movement control unit 41 is positioned at the imaging start position where the X-ray is actually irradiated and the imaging is started after the imaging range is confirmed by the projector provided in the gantry device 10 (step S <b> 8). S201). Note that, at the imaging start position, the traveling direction of the gantry device 10 and the imaging cross section of the gantry device 10 are orthogonal to each other. Subsequently, the movement control unit 41 acquires a scan condition (step S202). For example, the movement control unit 41 acquires scan conditions from the scan control unit 33.

  When the movement control unit 41 receives an instruction to start photographing from the operator, the movement control unit 41 controls the drive motor 45 to drive the drive wheels 43 to move a predetermined distance (step S203). Note that the movement control unit 41 moves, and imaging of the subject P placed on the bed apparatus 20 is started. Here, in a general X-ray CT apparatus, for example, by driving on a rail with a ball screw, the traveling direction at the time of imaging is controlled to be orthogonal to the imaging cross section. On the other hand, the X-ray CT apparatus according to the first embodiment is not driven by a ball screw. For this reason, in the gantry device 10 according to the first embodiment, the movement control unit 41 causes the traveling direction and the imaging cross section of the gantry device 10 to be orthogonal each time the gantry device 10 is moved during photographing. To control the moving direction.

  The movement control unit 41 acquires the current position information P1 and P2 from the position information acquisition unit 48 (step S204). Then, the movement control unit 41 determines whether or not the traveling direction and the imaging section are orthogonal (step S205). For example, the movement control unit 41 according to the first embodiment determines whether or not the current position information P1 and P2 are located on coordinates that can be advanced at the time of shooting determined in advance, so that the traveling direction is determined. And whether or not the imaging cross section is orthogonal.

  As a specific example, a case will be described in which the gantry device 10 travels in the Z-axis direction, and the traveling direction is orthogonal to the imaging cross section of the gantry device 10. Further, a set of coordinates that can be traveled by the gantry device 10 at the time of photographing is R1 (1, 2,..., N) and R2 (1, 2,..., N). Here, when the traveling direction and the imaging section taken by the gantry device 10 are orthogonal, the current position information P1 coincides with any coordinate on R1 (1, 2,..., N), and the current position information P2 matches any coordinate on R2 (1, 2,..., N), and the Z coordinates of the current position information P1 and P2 match. Therefore, the movement control unit 41 has P1 on R1 (1, 2,..., N), P2 on R2 (1, 2,..., N), and When the Z coordinates of P1 and P2 coincide with each other, it is determined that the traveling direction and the imaging section taken by the gantry device 10 are orthogonal.

  If the movement control unit 41 determines that the traveling direction and the imaging section are orthogonal (step S205, Yes), the movement control unit 41 proceeds to step S207. On the other hand, when the movement control unit 41 does not determine that the traveling direction and the imaging section are orthogonal (No in step S205), the movement control unit 41 corrects the position so that the traveling direction and the imaging section are orthogonal (step S206). For example, the movement control unit 41 has P1 on R1 (1, 2,..., N), P2 on R2 (1, 2,..., N), and P1 and P2. The current position is corrected so that the Z coordinates coincide. Then, the movement control unit 41 determines whether or not the photographing is finished after correcting the position (step S207).

  If the movement control unit 41 determines that shooting has ended (step S207, Yes), it ends the process. On the other hand, when the movement control unit 41 does not determine that the shooting has ended (No in step S207), the movement control unit 41 proceeds to step S203, and repeats the processes from step S203 to step S207 until it is determined that the shooting has ended. Run.

  As described above, according to the first embodiment, the gantry device 10 is driven by wheels and moves on the floor surface. For this reason, the rail for making the mount apparatus 10 drive is not required. That is, the gantry device 10 according to the first embodiment can be self-propelled without preparing a special floor for the gantry device 10 to self-propel. For this reason, according to 1st Embodiment, even if the environment in the space where an X-ray CT apparatus is arrange | positioned changes, it becomes possible for the gantry apparatus 10 to change operation | movement easily. That is, the use restriction of the examination room can be reduced.

  In addition, the gantry device 10 according to the first embodiment can be stopped at the retracted position, for example, when shooting is not performed. Thereby, according to 1st Embodiment, it becomes possible to use widely the space in which the X-ray CT apparatus was installed.

  Moreover, according to 1st Embodiment, it is not necessary to embed the ball screw for driving the mount apparatus 10 under a floor. Thereby, when installing an X-ray CT apparatus, the cost of the construction which installs a rail can be reduced.

  Moreover, according to 1st Embodiment, the rail for making the gantry device 10 drive is not required. For this reason, in 1st Embodiment, it can prevent that an operator trips over a rail or falls.

  Further, for example, blood of the subject P or a liquid substance used during the operation may be dropped on the floor 3 during the operation by the doctor. In the first embodiment, since the rail is not provided, the liquid substance does not enter the rail. Moreover, since the screw which becomes an obstacle at the time of cleaning is not provided, the cleaning of the floor surface 3 on which the X-ray CT apparatus travels can be facilitated.

  Further, the gantry device 10 can freely move in the space. For this reason, for example, even when a liquid substance is dropped on the floor surface, the floor surface 3 can be easily cleaned by moving the gantry device 10. Thereby, improvement in hygiene can be expected.

  Further, according to the first embodiment, the tire member 43a of the drive wheel 43 is made of a slip-resistant rubber material, so that, for example, blood of the subject P is scattered on the floor 3 during the operation. Even in this case, the drive wheel 43 can prevent slipping on the floor surface 3.

  In addition, according to 1st Embodiment, although the light-receiving part 49 demonstrated as what was provided in the upper part of the mount apparatus 10, embodiment is not limited to this. For example, the light receiving unit 49 may be provided on the left and right side surfaces, the front surface, and the back surface of the gantry device 10. In such a case, each projector 2 is installed on the side wall in the space where the X-ray CT apparatus is arranged. Each light receiving unit 49 senses light emitted from each projector 2. Then, the position information acquisition unit 48 acquires position information of the current position of the gantry device 10 from the light sensed by each light receiving unit 49. Note that the installation position and number of the projectors 2 and the installation position and number of the light receiving units 49 can be arbitrarily set as long as two pieces of position information of the current position of the gantry device 10 can be acquired.

  In addition, according to the first embodiment, by determining whether or not the current position information P1 and P2 are located on coordinates that can be advanced at the time of shooting determined in advance, the traveling direction and the imaging cross section are determined. However, the embodiment is not limited to this. For example, the position information P1 and P2 are acquired every time the gantry device 10 moves, and it is determined whether or not the vector P1P2 determined by the P1 and P2 is in a parallel relationship before and after the movement. It may be determined whether or not the imaging section is orthogonal. For example, when the vector P1P2 before movement and the vector P1P2 after movement are in a parallel relationship, the movement control unit 41 determines that the traveling direction and the imaging section are orthogonal.

  Further, according to the first embodiment, the gantry device 10 includes the movement control unit 41, the drive unit 42a, the drive unit 42b, the drive unit 42c, the drive unit 42d, the position information acquisition unit 48, and the light receiving unit 49a. However, the embodiment is not limited to this. For example, the transport unit including the movement control unit 41, the drive unit 42 a, the drive unit 42 b, the drive unit 42 c, the drive unit 42 d, the position information acquisition unit 48, the light receiving unit 49 a, and the light receiving unit 49 b is connected to the gantry device 10. May be provided independently. In such a case, for example, by fixing an existing gantry device on a box-shaped housing having a transport unit, the existing gantry device can be easily switched to a movable gantry device.

(Second Embodiment)
In the first embodiment, the case where the gantry device 10 senses the light emitted from the projector 2 installed on the ceiling 1 and detects the position information of the gantry device 10 has been described. However, the detection of position information by the gantry device 10 is not limited to this. For example, the gantry device 10 may acquire position information by reading an encoder installed on the floor surface 3. For this reason, in the second embodiment, a case will be described in which the gantry device 10 acquires position information by reading an encoder installed on the floor surface 3.

  FIG. 9 is a perspective view showing an X-ray CT apparatus according to the second embodiment. As shown in FIG. 9, the X-ray CT apparatus according to the second embodiment includes a gantry device 10 a and a console device 30. The bed apparatus 20 is not included in the X-ray CT apparatus. The bed apparatus 20 is an apparatus on which the subject P is placed, and may be a bed of another medical image diagnostic apparatus or an operating table.

  In FIG. 9, as in FIG. 1, an orthogonal coordinate system including the X axis, the Y axis, and the Z axis is defined. That is, the X axis indicates the horizontal direction, the Y axis indicates the vertical direction, and the Z axis indicates the traveling direction of the gantry device 10a during imaging of the subject P placed on the bed apparatus 20.

  The functional configuration of the gantry device 10a according to the second embodiment is the same as that shown in FIG. 2 except that some of the functions of the position information acquisition unit 48 are different and the light receiving unit 49a and the light receiving unit 49b are not provided. This is the same as the functional configuration of the gantry device 10 according to the first embodiment. The functional configuration of the console device 30 is the same as the functional configuration of the console device 30 according to the first embodiment shown in FIG.

  As shown in FIG. 9, an encoder 60 is attached to the floor surface 3 along the X-axis direction and the Z-axis direction. In addition, although detailed illustration is abbreviate | omitted in FIG. 9, the encoder 60 shall be attached to the whole region of the floor surface 3 in the space where an X-ray CT apparatus is arrange | positioned with a predetermined space | interval.

  Further, the gantry device 10a according to the second embodiment includes a position information acquisition unit 48a and a position information acquisition unit 48b. The position information acquisition unit 48a and the position information acquisition unit 48b according to the second embodiment are installed on the floor surface 3 side of the gantry device 10a, and when the gantry device 10a travels on the floor surface 3, the floor surface The position information indicated by the encoder 60 installed in 3 is optically read.

  Then, the position information acquisition unit 48a and the position information acquisition unit 48b according to the second embodiment acquire the current position information of the gantry device 10a based on the read position information. For example, the position information read by the position information acquisition unit 48a is EP1, and the position information read by the position information acquisition unit 48b is EP2. The encoder 60 is preferably arranged in a grid shape and is attached so that the width of each grid is within a readable range of the position information acquisition unit 48a and the position information acquisition unit 48b. Further, after the encoder 60 is attached to the floor 3, the encoder 60 may be covered with rubber, for example.

  FIG. 10 is a diagram for explaining detection of position information by the X-ray CT apparatus according to the second embodiment. In FIG. 10, the figure which looked at the floor surface 3 from the ceiling 1 side is shown. As shown in FIG. 10, an encoder 60 is attached along the X-axis direction and the Z-axis direction. Here, for example, as shown in FIG. 10, detection of position information when the center of the position information acquisition unit 48a is on the position indicated by EP1 will be described.

  The position information acquisition unit 48a reads the coordinates of point A and point C that are in the Z-axis direction from EP1 and are intersections with the encoder 60 along the X-axis. In the example illustrated in FIG. 10, the position information acquisition unit 48a reads the coordinates of the point A as (X2, Z3) and the coordinates of the point C as (X2, Z1). The position information acquisition unit 48a reads the coordinates of points B and D, which are in the X-axis direction from EP1 and are the intersections with the encoder 60 along the Z-axis. In the example illustrated in FIG. 10, the position information acquisition unit 48a reads the coordinates of the point B as (X1, Z2) and the coordinates of the point D as (X3, Z2).

  Subsequently, the position information acquisition unit 48a estimates the coordinates of EP1 from the coordinates of the read points A, B, C, and D. In the example shown in FIG. 10, the position information acquisition unit 48a estimates the coordinates of EP1 as (X2, Z2). The position information acquisition unit 48b reads the position information in the same manner. As described above, the position information acquisition unit 48a and the position information acquisition unit 48b according to the second embodiment acquire the position information of the gantry device 10a. As a result, when the gantry device 10a moves, the gantry device 10a can grasp position information (absolute position) at the destination.

  Further, the position information acquisition unit 48 a and the position information acquisition unit 48 b according to the second embodiment output the acquired position information to the movement control unit 41.

  And the movement control part 41 determines whether a target position and the acquired positional information correspond, when the instruction | indication which moves to the target position represented by Q1 and Q2 is received from the operator. For example, the movement control unit 41 determines that the target position matches the acquired position information when EP1 matches Q1 and the position information EP2 matches Q2. Thereby, for example, the X-ray CT apparatus can position the gantry device 10a to a position where the subject P placed on the bed apparatus 20 can be imaged.

  Further, the movement control unit 41 controls the movement direction so that the traveling direction and the imaging cross section of the gantry device 10 are orthogonal each time the gantry device 10a is moved during photographing. For example, the movement control unit 41 acquires the current position information EP1 from the position information acquisition unit 48a, and acquires the current position information EP2 from the position information acquisition unit 48b. Then, the movement control unit 41 determines whether or not the traveling direction and the imaging section are orthogonal.

  As described above, according to the second embodiment, the gantry device 10a is driven by wheels and moves on the floor surface. For this reason, the rail for making the mount apparatus 10a run is not required. Further, it is not necessary to embed a ball screw for driving the gantry device 10a under the floor. Thereby, when installing an X-ray CT apparatus, the cost of the construction which installs a rail can be reduced.

  Moreover, according to 2nd Embodiment, the rail for making the gantry 10a run is not required. For this reason, in 2nd Embodiment, it can prevent that an operator stumbles on a rail or falls.

  Further, for example, blood of the subject P or a liquid substance used during the operation may be dropped on the floor 3 during the operation by the doctor. In the second embodiment, since the rail is not provided, the liquid substance does not enter the rail. Moreover, since the screw which becomes an obstacle at the time of cleaning is not provided, the cleaning of the floor surface 3 on which the X-ray CT apparatus travels can be facilitated.

  Furthermore, the gantry device 10a can freely move in the space. For this reason, for example, even when a liquid substance is dropped on the floor surface 3, the floor surface can be easily cleaned by moving the gantry device 10a. Thereby, improvement in hygiene can be expected.

  Further, according to the second embodiment, the tire member 43a of the drive wheel 43 is made of a rubber material having slip resistance, so that, for example, blood of the subject P is scattered on the floor 3 during the operation. Even in this case, the drive wheel 43 can prevent slipping on the floor surface 3.

  In the above-described embodiment, the encoder 60 has been described as being attached to the entire area of the floor surface 3 in the space where the X-ray CT apparatus is disposed at a predetermined interval. It is not limited to this. For example, the encoder 60 may be attached only to a predetermined area including the bed apparatus 20. In such a case, for example, when the gantry device 10a is located in an area where the encoder 60 is not attached, the movement of the gantry device 10a is controlled by a remote controller operated by the operator. Then, the gantry device 10a moves to the area where the encoder 60 is attached, and then self-runs based on the position information read by the position information acquisition unit 48. In such a case, after the gantry device 10a moves to the area where the encoder 60 is attached, the gantry device 10a is self-propelled within the area where the encoder 60 is attached, and the area where the encoder 60 is not attached is operated. If no instruction is given by the person, the vehicle may not run.

  Further, the number of the position information acquisition units 48 to be installed is not limited to the number illustrated in FIG. 9, and can be arbitrarily set as long as two pieces of position information at the current location of the gantry device 10a can be acquired. .

  The position information acquisition unit 48 may be of a contact type that reads position information by contacting the encoder 60. Alternatively, the position information acquisition unit 48 may be a magnetic sensor that magnetically reads the position information indicated by the encoder 60.

  In addition, according to the second embodiment, the gantry device 10a includes the movement control unit 41, the drive unit 42a, the drive unit 42b, the drive unit 42c, the drive unit 42d, the position information acquisition unit 48a, and the position information acquisition unit. However, the embodiment is not limited to this. For example, the transfer unit including the movement control unit 41, the drive unit 42a, the drive unit 42b, the drive unit 42c, the drive unit 42d, the position information acquisition unit 48a, and the position information acquisition unit 48b is independent of the gantry device 10a. It may be provided. In such a case, for example, by fixing an existing gantry device on a box-shaped housing having a transport unit, the existing gantry device can be easily switched to a movable gantry device.

(Other embodiments)
The embodiment is not limited to the above-described embodiment.

  In the embodiment described above, the gantry device 10 (10a) has been described as moving to the target position by the shortest route at the time of non-photographing, but the embodiment is not limited to this. For example, the gantry device 10 (10a) may store a plurality of movement paths and move to the target position along the movement path selected by the operator.

  Further, the gantry device 10 (10a) may store, for example, a procedure for each doctor as movement control at the time of photographing, and may move the gantry device 10 (10a) according to the procedure of the doctor. For example, in a procedure by a doctor, there is a case where imaging with an X-ray CT apparatus and surgery are alternately repeated for the same subject P. More specifically, the gantry device 10 (10a) moves, for example, to a position where the subject P placed on the couch device 20 can be imaged. Then, the gantry device 10 (10a) images the subject P placed on the couch device 20. Subsequently, the gantry device 10 (10a) moves to a position away from the couch device 20 so that a space for a doctor to perform an operation can be secured. Subsequently, for example, the doctor identifies a surgical site using a medical image captured by the X-ray CT apparatus, and operates the identified site. Moreover, after the specified site | part is operated by a doctor, the operated site | part may be image | photographed. In such a case, the gantry device 10 moves again to a position where the subject P placed on the couch device 20 can be imaged. Thus, the gantry device 10 (10a) reciprocates between the position away from the couch device 20 and the photographing position many times so that a space for performing the operation can be secured. For this reason, the gantry device 10 (10a) stores a position away from the couch device 20 and a photographing position so that a space for performing surgery can be secured, and in response to an instruction from the operator, These two positions may be reciprocated.

  In the above-described embodiment, the position information storage unit 39 has been described as storing, for example, the coordinates where the couch device 20 is arranged, the coordinates where the console device 30 is arranged, the coordinates of the target position, and the like. It is not limited to this. For example, the position information storage unit 39 may store coordinates of an interference object or an obstacle installed in the space. In this case, for example, when moving to the target position, the gantry device 10 (10a) selects a path that bypasses the interferer or obstacle when an interferer or obstacle is placed on the path. Alternatively, a “mat switch” or the like may be attached to an obstacle or an obstacle. Thereby, the gantry device 10 (10a) can detect an interference object or an obstacle, and can prevent a collision with the interference object or the obstacle.

  Note that a power cable for supplying power is connected to the gantry device 10 (10a). This power cable is attached, for example, so as to crawl the ceiling. Here, in the X-ray CT apparatus according to the first and second embodiments, the power cable is provided with play so that the gantry device 10 (10a) can freely travel on the floor surface 3, and the ceiling A mechanism to move the cable may be provided.

  In the above-described embodiment, each of the four drive units 42 is driven. However, the embodiment is not limited to this. For example, the front left drive unit 42a and the front right drive unit 42b may be driven, and the rear left drive unit 42c and the rear right drive unit 42d may be driven. In such a case, the driving wheel rotates by obtaining power from the driving motor 45, and the driven wheel rotates according to the force generated by the traveling of the driving wheel.

  Moreover, although embodiment mentioned above demonstrated as what can control the advancing direction of each of the four drive parts 42, embodiment is not limited to this. For example, the traveling directions of the front left driving unit 42a and the front right driving unit 42b may be controlled, and the traveling directions of the rear left driving unit 42c and the rear right driving unit 42d may be fixed. Further, the traveling directions of the four drive units 42 may be controlled at different angles.

  In the above-described embodiment, the self-propelled type that obtains power from the drive motor 45 has been described as an example, but the embodiment is not limited thereto. For example, when not photographing, the gantry device 10 may be manually moved to the photographing start position. Similarly, when not photographing, the gantry device 10 may be manually moved from the photographing end position.

  Further, in the above-described embodiment, the gantry device 10 (10a) has been described as being driven by a tire by a wheel, but the embodiment is not limited to this. For example, the gantry device 10 (10a) may be driven by a belt system using wheels.

  In the above-described embodiment, an example in which the bed apparatus 20 is fixedly installed on the floor surface 3 has been described. However, the embodiment is not limited thereto, and for example, the bed apparatus is a belt type or a tire type by a wheel. May be driven to travel on the floor surface 3.

  According to at least one embodiment described above, it is possible to provide an X-ray CT apparatus capable of extending the movable range.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 10 Stand apparatus 20 Bed apparatus 30 Console apparatus 41 Movement control part 42 Drive part 48 Position information acquisition part

Claims (6)

A position information acquisition unit that acquires position information of the current position of the gantry device;
A movement control unit that controls the drive unit with reference to the position information and moves the gantry device;
An X-ray CT apparatus comprising:   2. The X-ray CT according to claim 1, wherein the movement control unit moves the gantry device so that a traveling direction of the gantry device and an imaging cross section of the gantry device are orthogonal to each other during imaging. apparatus. The position information acquisition unit always acquires position information at the current location of the gantry device at the time of shooting,
While the movement control unit moves the gantry device from the photographing start point to the photographing end point, the movement direction of the gantry device and the photographing cross section by the gantry device are determined based on the acquired position information at the current location. The X-ray CT apparatus according to claim 2, wherein a traveling direction of the gantry device is controlled so as to be orthogonal to each other. A storage unit for storing a predetermined movement route;
The X-ray CT apparatus according to claim 1, wherein the movement control unit moves the gantry device based on a movement path stored in the storage unit. An operation receiving unit that receives an operation of moving the gantry device by an operator;
The X-ray CT apparatus according to claim 1, wherein the movement control unit moves the gantry according to the operation received from an operator. The drive unit includes a drive wheel and a rotation mechanism that is connected to the drive wheel and controls the traveling direction of the drive wheel to be rotatable,
The X-ray CT apparatus according to claim 1, wherein the movement control unit controls a traveling direction of the gantry device by controlling a rotation angle of the rotation mechanism.

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