JP2020065631A - Medical image diagnostic system - Google Patents

Abstract

To reduce the burden of preparation on an operator for medical imaging.SOLUTION: A medical image diagnostic system includes a storage unit and a selection unit. The storage unit stores a plurality of scan parameter sets. The selection unit selects at least one scan parameter set from the plurality of scan parameter sets on the basis of the position information correlated with the physical relation between a subject and a scan unit acquired following the movement of the subject or the scan unit scanning the subject.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a medical image diagnostic system.

  In X-ray computed tomography, various preparations regarding imaging, such as guiding a patient to a bed, setting up an imaging position, inputting patient information, and setting up an optional unit, are required. After these preparations are completed, the scan plan is selected, then the apparatus is set up, and the photographing is finally performed.

JP, 03-70547, A JP, 2007-167634, A JP, 2009-60939, A JP, 11-235334, A

  The problem to be solved by the present invention is to reduce the preparation burden on the operator for medical imaging.

  The medical image diagnostic system according to the embodiment is a storage unit that stores a plurality of scan parameter sets, and a subject or a scan unit that is acquired with the movement of a scan unit that scans the subject, of the subject and the scan unit. A selection unit that selects at least one scan parameter set from the plurality of scan parameter sets based on the position information correlated with the positional relationship.

FIG. 1 is a diagram showing a configuration of an X-ray CT system according to this embodiment. FIG. 2 is a diagram showing the appearance of the gantry and the bed of FIG. FIG. 3 is a diagram showing a workflow of a CT examination related to the X-ray CT system of FIG. FIG. 4 is a diagram showing an example of the scan plan table. FIG. 5 is a diagram schematically showing the relationship between the top plate position and the scan plan. FIG. 6 is a diagram showing a typical flow of a series of processes relating to the scan plan selection process executed by the processing circuit in step S5 of FIG. FIG. 7 is a diagram schematically showing the scan plan candidate selection process performed in step SA2 of FIG. FIG. 8 is a diagram showing an example of a default scan plan selection screen. FIG. 9 is a diagram showing a scan plan selection screen displayed in step SA3 of FIG. FIG. 10 is a diagram showing another scan plan selection screen displayed in step SA3 of FIG. FIG. 11 is a diagram showing another scan plan selection screen displayed in step SA3 of FIG. FIG. 12 is a diagram showing another scan plan selection screen displayed in step SA3 of FIG. FIG. 13 is a diagram showing the position of the tabletop when the head is photographed in a medical facility where the luggage is not placed on the tabletop. FIG. 14 is a diagram showing the position of the tabletop when the head is photographed in a medical facility where luggage is placed on the tabletop. FIG. 15 is a diagram showing a flow from selection of a scan plan to imaging by the processing circuit according to the modified example 1 of the present embodiment.

  Hereinafter, the medical image diagnostic system according to the present embodiment will be described with reference to the drawings.

  The medical image diagnostic system according to the present embodiment is a system related to a medical image diagnostic apparatus that generates a medical image. As the medical image diagnostic apparatus, an X-ray computed tomography apparatus, a magnetic resonance imaging apparatus, an X-ray diagnostic apparatus, a nuclear medicine diagnostic apparatus, etc. can be used. In order to make the description specifically, a system related to an X-ray computed tomography apparatus (hereinafter referred to as an X-ray CT system) will be described as an example of a medical image diagnostic system.

  FIG. 1 is a diagram showing a configuration of an X-ray CT system 1. Although a plurality of pedestals 10 are shown in FIG. 1 for convenience of explanation, the gantry 10 equipped in the X-ray CT system 1 is typically one.

  As shown in FIG. 1, the X-ray CT system 1 has a gantry 10, a bed 30, and a console 40. The gantry 10 is a scanning device having a configuration for X-ray CT imaging the subject P. The bed 30 is a transport device for placing the subject P, which is the target of X-ray CT imaging, and positioning the subject P. The console 40 is a computer that controls the gantry 10. For example, the gantry 10 and the bed 30 are installed in an examination room, and the console 40 is installed in an operation room adjacent to the examination room. The gantry 10, the bed 30, and the console 40 are connected by wire or wirelessly so that they can communicate with each other. The gantry 10 is an example of a scanning unit.

  As shown in FIG. 1, the gantry 10 includes an X-ray tube 11, an X-ray detector 12, a rotary frame 13, an X-ray high voltage device 14, a controller 15, a wedge 16, a collimator 17, and a data acquisition circuit (DAS: Data). Acquisition System) 18.

  The X-ray tube 11 generates X-rays. Specifically, X-ray tube 11 includes a cathode that generates thermoelectrons, an anode that receives thermoelectrons flying from the cathode to generate X-rays, and a vacuum tube that holds the cathode and the anode. The X-ray tube 11 is connected to the X-ray high voltage device 14 via a high voltage cable. A filament current is supplied to the cathode by the X-ray high voltage device 14. The supply of filament current causes thermoelectrons to be generated from the cathode. A tube voltage is applied by the X-ray high voltage device 14 between the cathode and the anode. When a tube voltage is applied, thermoelectrons fly from the cathode toward the anode and collide with the anode, generating X-rays. The generated X-rays are applied to the subject P. A tube current flows by thermionic electrons flying from the cathode to the anode.

  The X-ray detector 12 detects X-rays generated from the X-ray tube 11 and passed through the subject P, and outputs an electric signal corresponding to the detected dose of X-rays to the DAS 18. The X-ray detector 12 has a structure in which a plurality of X-ray detection element rows in which a plurality of X-ray detection elements are arranged in the channel direction are arranged in the slice direction (row direction). The X-ray detector 12 is, for example, an indirect conversion type detector including a grid, a scintillator array, and a photosensor array. The scintillator array has a plurality of scintillators. The scintillator outputs a light amount corresponding to the incident X-ray dose. The grid is arranged on the X-ray incidence surface side of the scintillator array and has an X-ray shield that absorbs scattered X-rays. The grid may be called a collimator (one-dimensional collimator or two-dimensional collimator). The optical sensor array converts the light from the scintillator into an electric signal according to the amount of light. For example, a photodiode is used as the optical sensor.

  The rotating frame 13 is an annular frame that supports the X-ray tube 11 and the X-ray detector 12 rotatably around the rotation axis Z. Specifically, the rotating frame 13 supports the X-ray tube 11 and the X-ray detector 12 so as to face each other. The rotating frame 13 is supported by a fixed frame (not shown) so as to be rotatable around the rotation axis Z. The rotation frame 13 is rotated about the rotation axis Z by the control device 15 to rotate the X-ray tube 11 and the X-ray detector 12 about the rotation axis Z. An image field of view (FOV: Field Of View) is set in the opening 19 of the rotating frame 13.

  In the present embodiment, the longitudinal direction of the rotary shaft of the rotary frame 13 or the top plate 33 of the bed 30 in the non-tilt state is the Z direction, and the direction orthogonal to the Z direction and horizontal to the floor is the X direction. The direction orthogonal to the direction and perpendicular to the floor is defined as the Y direction.

  The X-ray high voltage device 14 has a high voltage generator and an X-ray controller. The high voltage generator has an electric circuit such as a transformer and a rectifier, and generates a high voltage applied to the X-ray tube 11 and a filament current supplied to the X-ray tube 11. The X-ray controller controls the high voltage applied to the X-ray tube 11 and the filament current supplied to the X-ray tube 11. The high voltage generator may be a transformer type or an inverter type. The X-ray high voltage device 14 may be provided on the rotary frame 13 in the gantry 10 or may be provided on a fixed frame (not shown) in the gantry 10.

  The wedge 16 adjusts the dose of X-rays with which the subject P is irradiated. Specifically, the wedge 16 attenuates the X-ray so that the dose of the X-ray emitted from the X-ray tube 11 to the subject P has a predetermined distribution. For example, the wedge 16 is a metal filter formed by processing a metal such as aluminum, such as a wedge filter or a bow-tie filter. These wedges 16 are processed so as to have a predetermined target angle and a predetermined thickness.

  The collimator 17 limits the irradiation range of the X-ray transmitted through the wedge 16. The collimator 17 slidably supports a plurality of lead plates that shield X-rays and adjusts the form of slits formed by the plurality of lead plates. The collimator 17 is also called an X-ray diaphragm.

  The DAS 18 reads the electric signal corresponding to the dose of the X-ray detected by the X-ray detector 12 from the X-ray detector 12, amplifies the read electric signal, and integrates the electric signal over the view period. Collect detection data with digital values as a function of X-ray dose over the view period. The detection data is also called projection data. The DAS 18 is realized by, for example, an application-specific integrated circuit (ASIC) equipped with a circuit element capable of generating projection data. The projection data (detection data) generated by the DAS 18 is emitted from a transmitter having a light emitting diode (LED) provided on the rotating frame 13 and is provided on a non-rotating portion (for example, a fixed frame) of the gantry 10 by optical communication. It is transmitted to a receiver having a diode (LED) and transmitted from the receiver to the console 40. The method of transmitting the projection data from the rotating frame 13 to the non-rotating portion of the gantry 10 is not limited to the optical communication described above, and any method may be used as long as it is non-contact data transmission.

  The bed 30 includes a base 31, a support frame 32, a top plate 33, and a bed driving device 34. The base 31 is installed on the floor. The base 31 is a structure that supports the support frame 32 so as to be movable in the vertical direction (Y direction) with respect to the floor surface. The support frame 32 is a frame provided above the base 31. The support frame 32 supports the top plate 33 slidably along the central axis Z. The top plate 33 is a flexible plate-like structure on which the subject P is placed.

  The bed driving device 34 is housed in the bed 30. The bed driving device 34 is a motor or an actuator that generates power for moving the top plate 33 on which the subject P is placed. The bed driving device 34 operates under the control of the console 40 or the like.

  The control device 15 controls the X-ray high voltage device 14, the DAS 18, and the bed 30 in order to execute the X-ray CT imaging according to the imaging control function 441 by the processing circuit 44 of the console 40. The control device 15 has a processing circuit having a CPU (Central Processing Unit) and the like, and drive devices such as a motor and an actuator. The processing circuit has, as hardware resources, a processor such as a CPU and a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The control device 15 controls the gantry 10 and the bed 30 according to an operation signal from the input interface 43 provided on the console 40, the gantry 10, the bed 30 and the like, for example. For example, the control device 15 controls the rotation of the rotary frame 13, the tilt of the gantry 10, and the operations of the top plate 33 and the bed 30.

  The console 40 has a memory 41, a display 42, an input interface 43, and a processing circuit 44. Data communication among the memory 41, the display 42, the input interface 43, and the processing circuit 44 is performed via a bus (BUS). Although the console 40 is described as being separate from the gantry 10, the gantry 10 may include all or some of the components of the console 40.

  The memory 41 is a storage device such as an HDD (Hard Disk Drive), an SSD (Solid State Drive), or an integrated circuit storage device that stores various information. The memory 41 stores, for example, projection data and reconstructed image data. The memory 41 may be a portable storage medium such as a CD (Compact Disc), a DVD (Digital Versatile Disc) and a flash memory, a semiconductor memory device such as a RAM (Random Access Memory), etc. other than the HDD and the SSD. It may be a drive device that reads and writes various information. The storage area of the memory 41 may be in the X-ray CT system 1 or in an external storage device connected by a network. The memory 41 specifically stores a plurality of scan parameter sets. The scan parameter set is a combination of values of a plurality of types of scan parameters. The scan parameter set is synonymous with the scan plan (expert plan). The plurality of scan parameter sets are stored, for example, in a LUT (look up table) format. This LUT will be called a scan plan table.

  The display 42 displays various information. For example, the display 42 outputs a medical image (CT image) generated by the processing circuit 44, a GUI (Graphical User Interface) for receiving various operations from the operator, and the like. For example, as the display 42, for example, a liquid crystal display (LCD: Liquid Crystal Display), a CRT (Cathode Ray Tube) display, an organic EL display (OELD: Organic Electro Luminescence Display), a plasma display, or any other display is appropriately used. , Is ready for use. Further, the display 42 may be provided on the gantry 10. The display 42 may be a desktop type or a tablet type included in a tablet terminal or the like that can wirelessly communicate with the console 40 body.

  The input interface 43 receives various input operations from the operator, converts the received input operations into electric signals, and outputs the electric signals to the processing circuit 44. As the input interface 43, for example, a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touch pad, a touch panel display or the like can be appropriately used. In the present embodiment, the input interface 43 is not limited to the one including a physical operation component such as a mouse, a keyboard, a trackball, a switch, a button, a joystick, a touch pad and a touch panel display. For example, the input interface 43 also includes an electric signal processing circuit that receives an electric signal corresponding to an input operation from an external input device provided separately from the device and outputs the electric signal to the processing circuit 44. . The input interface 43 may be provided on the gantry 10. Further, the input interface 43 may be included in a tablet terminal or the like that can wirelessly communicate with the console 40 body.

  The processing circuit 44 controls the operation of the X-ray CT system 1 according to the electric signal of the input operation output from the input interface 43. For example, the processing circuit 44 has, as hardware resources, a processor such as a CPU and a GPU (Graphics Processing Unit) and a memory such as a ROM and a RAM. The processing circuit 44 executes the program loaded in the memory to execute the imaging control function 441, the reconstruction function 442, the image processing function 443, the information acquisition function 444, the scan planning function 445, the display control function 446, and the calibration function 447. And so on. The functions 441 to 447 are not limited to being realized by a single processing circuit. A plurality of independent processors may be combined to form a processing circuit, and each processor may execute a program to realize each of the functions 441 to 447.

  In the imaging control function 441, the processing circuit 44 controls the X-ray high voltage device 14, the control device 15, and the DAS 18 to perform X-ray CT imaging. The processing circuit 44 controls the X-ray high-voltage device 14, the controller 15, and the DAS 18 according to the imaging conditions determined by the scan planning function 445.

  In the reconstruction function 442, the processing circuit 44 generates a CT image based on the projection data output from the DAS 18. Specifically, the processing circuit 44 performs preprocessing such as logarithmic conversion processing, offset correction processing, interchannel sensitivity correction processing, and beam hardening correction on the projection data output from the DAS 18. Then, the processing circuit 44 performs a reconstruction process using the filtered back projection method, the successive approximation reconstruction method, or the like on the preprocessed projection data to generate a CT image.

  In the image processing function 443, the processing circuit 44 converts the CT image generated by the reconstruction processing function 442 into a tomographic image or a volume rendering image of an arbitrary section based on the input operation received from the operator via the input interface 43. Convert.

  In the information acquisition function 444, the processing circuit 44 acquires position information that correlates with the positional relationship between the subject P and the gantry 10 as the subject P or the gantry 10 that scans the subject P moves.

  In the scan plan function 445, the processing circuit 44 makes a scan plan automatically or according to an instruction from the operator input via the input interface 43 or the like. In the scan plan, the processing circuit 44, based on the position information acquired by the information acquisition function 444, selects one or more scans from a plurality of scan parameter sets (in other words, a scan plan table) stored in the memory 41. Select a parameter set. When a plurality of scan parameter sets are selected, the processing circuit 44 selects one scan parameter set automatically or manually via the input interface 43.

  In the display control function 446, the processing circuit 44 displays various information on the display 42. For example, one or more selected scan parameter sets are displayed as various information. Further, a CT image or the like is displayed as various information.

  In the calibration function 447, the processing circuit 44 calibrates the scan plan table based on the mechanical constraint on the moving range of the bed 30 or the gantry 10 of the own device.

  The operation of the X-ray CT system 1 will be described below.

  FIG. 2 is a diagram showing appearances of the gantry 10 and the bed 30. As shown in FIG. 2, the gantry 10 has a gantry body 23 in which a substantially cylindrical opening 19 is formed. The gantry body 23 is supported by a fixing portion 25 installed on the floor so as to be tiltable around a tilt axis AT. The tilt axis AT is horizontally orthogonal to the central axis (rotation axis) AR of the opening 19. A bed 30 is installed in front of the gantry 10. As shown in FIG. 2, the bed 30 is arranged such that the long axis A1 of the top plate 33 is parallel to the central axis AR of the opening 19.

  The support frame 32 supports the top plate 33 slidably along the major axis A1. The base 31 supports the top plate 33 so as to be able to move up and down along a vertical axis A2 that is perpendicular to the long axis A1. The vertical axis A2 is perpendicular to the floor surface. Hereinafter, the direction parallel to the long axis A1 of the top plate 33 will be referred to as the long axis direction or the Z direction, and the direction parallel to the vertical axis A2 will be referred to as the vertical direction or the Y direction. Further, the direction in which the bed 30 approaches the gantry 10 is the + Z direction, the direction in which the bed 30 leaves the gantry 10 is the −Z direction, the direction in which the bed 30 rises is the + Y direction, and the direction in which the bed 30 descends is the −Y direction. . The limit reaching position of the top plate 33 on the + Z direction side is called IN-LIMIT, and the limit reaching position of the top plate 33 on the −Z direction side is called OUT-LIMIT.

  Next, with reference to FIG. 3, a workflow of a CT examination according to the X-ray CT system 1 according to the present embodiment will be described. The left column of FIG. 3 shows the work performed in the examination room in which the gantry 10 and the bed 30 are installed, and the right column of FIG. 3 shows the work performed in the operation room in which the console 40 is installed.

  As shown in FIG. 3, first, the console 40 in the operation room is switched to the next patient (step S1). For example, when the “next patient” button displayed on the display 42 is pressed by the operator such as a doctor or a technician via the input interface 43, the processing circuit 44 changes the patient to be processed by the system to the next patient (current patient). (Patient to be examined). By switching to the next patient, examination order information relating to the current examination subject patient is supplied to the console 40 from a network system such as RIS (Radiology Information System). The examination order information includes basic patient information regarding the patient currently being examined. The basic patient information includes basic information such as the name, patient ID, date of birth, etc. regarding the patient currently being examined. Hereinafter, the next patient or the patient to be inspected at present may be simply referred to as a patient.

  When step S1 is performed, the operator moves to the examination room and sets up the patient on the bed 30 (step S2). In step S2, the patient is laid on the top plate 33 of the bed 30.

  When step S2 is performed, the operator moves to the operation room and inputs patient information regarding the patient who is the current examination target into the console 40 (step S3). In step S3, the processing circuit 44 inputs patient information via the input interface 43 by the operator. The patient information that is input includes patient information that is not included in the examination order, for example, information regarding the imaged site and body position.

  When step S3 is performed, the operator moves to the examination room and sets up the patient position (step S4). In step S4, the operator operates the operation panel provided on the gantry 10 or the switch provided on the bed 30 because the imaged region of the patient is located in the image visual field. According to the operation, the control device 15 moves the top plate 33 along the Z-axis to move the top plate 33 into the bore 19, and arranges the imaging region of the patient in the imaging visual field. Specifically, the X-ray path from the X-ray tube 11 built in the gantry 10 to the X-ray detector 12 is positioned so that the X-ray path is located at the end on the gantry 10 side of both ends of the imaging range of the patient. The plate 33 is moved. This imaging range means the imaging range of the X-ray CT imaging that is first executed in the X-ray CT imaging in step S8. For example, when the X-ray CT imaging is performed in the order of the positioning scan (scano imaging) and the main scan in the X-ray CT imaging in step S8, the top plate is positioned so that the end of the imaging range of the positioning scan is located in the X-ray path. 33 is moved.

  When step S4 is performed, the operator moves to the operation room and selects a scan plan (step S5). In step S5, the processing circuit 44 selects the scan plan based on the positional information correlated with the positional relationship between the subject P and the gantry 10 by implementing the scan planning function 445. The process of step S5 will be described later.

  When step S5 is performed, the operator sets up the device via the console 40 (step S6). The apparatus setup means transition to a state in which the gantry 10 can immediately execute X-ray CT imaging, that is, preparation for X-ray CT imaging. As the apparatus setup, heating (heating up) of the X-ray tube 11 and rotation of the rotary frame 13 are performed.

  When steps S4 and S6 are performed, the operator waits until both the patient position setup and the device setup are completed (step S7).

  When both the patient position setup and the device setup are completed, the operator inputs an imaging start instruction through the input interface 43. Upon the input of the imaging start instruction, the processing circuit 44 controls the gantry 10 by the imaging control function 441 to execute the X-ray CT imaging. The gantry 10 irradiates X-rays from the X-ray tube 11 and detects X-rays by the X-ray detector 12 while rotating the rotating frame 13, and collects projection data regarding the patient for each view via the DAS 18. . The processing circuit 44 of the console 40 reconstructs a CT image based on the projection data by implementing the reconstruction function 442. The CT image is displayed on the display 42 or the like and is used for image interpretation or the like by the operator or the like. After the X-ray CT scan, the patient is removed from the examination room.

  With the above, the CT examination for the patient who is the current examination object is completed.

  Next, the selection of the scan plan in step S5 of FIG. 3 will be described in detail. As described above, in step S5, the processing circuit 44 selects a scan plan based on the positional information that correlates with the positional relationship between the subject P and the gantry 10. The positional information that correlates with the positional relationship between the subject P and the gantry 10 is defined in the position of the subject P, the position of the gantry 10, or the position of the top plate 33. The position of the gantry 10 is used when the gantry 10 has a configuration that is movable in the Z-axis direction via a rail provided on the floor surface along the Z-axis. In this embodiment, the gantry 10 is assumed to be fixed to the floor surface.

  First, a scan plan table used in selecting a scan plan will be described.

  FIG. 4 is a diagram showing an example of the scan plan table. As shown in FIG. 4, the scan plan table has a position of the top plate 33 (hereinafter, referred to as a top plate position) as position information correlating with the positional relationship between the subject P and the gantry 10 for each of the plurality of scan plans. Related information. The top plate position is defined as the position of the top plate 33 in the Z-axis direction. For example, when the top plate 33 is located at OUT-LIMIT, the top plate position is set to 0 mm. The scan plan is a combination of values of a plurality of types of scan parameters. The scan parameters constituting the scan plan include the tube voltage [kV], the tube current [mA], the imaging range [mm] in the Z-axis direction, the FOV size, the imaging site, and the like. The scan parameter may include other information such as the tilt angle of the gantry 10, the presence / absence of a contrast agent, the scan type, the reconstruction method, the type of the reconstruction function, and the like. The scan plan table is stored in the memory 41. The scan plan table may be stored in the memory provided in the gantry 10 instead of the memory 41 in the console 40, or may be stored in the storage area of the external server.

  The scan plan table is created in advance by the processing circuit 44 and the like. Specifically, the combination of the scan plan and the top position recorded in the scan plan table is the combination of the actually executed scan plan and the top position when the scan plan is selected. The processing circuit 44 specifies the top plate position when the scan plan is actually selected, specifies the actually executed scan plan, and stores the combination of the specified top plate position and the scan plan in the scan plan table. Record.

  FIG. 5 is a diagram schematically showing the relationship between the top plate position and the scan plan. As shown in FIG. 5, there is a relationship between the top plate position and the scan plan. That is, the top position is roughly determined according to the imaged region, and the tube voltage [kV], the tube current [mA], the imaging range [mm] in the Z-axis direction, the FOV size, etc. are scanned according to the imaged region. The parameters are roughly determined. For example, the upper part of FIG. 5 shows the scan plan 1, and the top plate position is 300 mm when the imaging site is the head. The middle part of FIG. 5 shows the scan plan 2, and the top plate position is 1000 mm when the imaging site is the chest of the scan plan 2. The lower part of FIG. 5 shows the scan plan 3, and the top plate position is 600 mm when the imaging site is the lower limb of the scan plan 3.

  FIG. 6 is a diagram showing a typical flow of a series of processes related to the scan plan selection process executed by the processing circuit 44 in step S5 of FIG. The process of FIG. 6 is performed in parallel with step S4 (patient position setup) shown in FIG.

  As shown in FIG. 6, the processing circuit 44 realizes the information acquisition function 444 to repeatedly acquire information on the current top position (step SA1). For example, the processing circuit 44 repeatedly acquires information regarding the top position during the period from patient switching (step S1) to imaging (step S8). For example, the bed driving device 34 is provided with a rotary encoder that outputs a signal indicating the position of the tabletop 33 in the Z-axis direction. The output signal from the rotary encoder is supplied to the console 40. The processing circuit 44 automatically acquires the output signal from the rotary encoder as the information related to the position of the tabletop during the movement of the tabletop 33 or when the tabletop 33 is moved. This top plate position represents the current top plate position.

  When step SA1 is performed, the processing circuit 44 selects a scan plan candidate based on the current top position by implementing the scan planning function 445 (step SA2). In step SA2, the processing circuit 44 compares the current top plate position acquired in step S1 with the top plate position of each scan plan registered in the scan plan table. Then, the processing circuit 44 selects, as a candidate, at least one scan plan associated with the top position that is close to the current top position. Specifically, the processing circuit 44 calculates the difference between the current top position and the top position of each scan plan registered in the scan plan table, and compares the calculated difference with a threshold value. The processing circuit 44 selects, as a candidate, a scan plan associated with a top plate position whose difference is smaller than the threshold value.

  FIG. 7 is a diagram schematically showing a scan plan candidate selection process performed in step SA2. As shown on the left side of FIG. 7, in the scan plan table, scan plan 1 (imaging site: head, top position: 300 mm), scan plan 2 (imaging site: chest, top position: 1000 mm), scan plan 3 It is assumed that (imaging site: lower limb, top plate position: 600 mm) is registered. Further, for example, assume that the current top position is 250 mm. In this case, the difference between the top plate position of the scan plan 1 and the current top plate position is 50 mm, the difference between the top plate position of the scan plan 2 and the current top plate position is 750 mm, and the top plate position of the scan plan 3 and the current top plate position. The difference from the top plate position of is 350 mm. For example, when the threshold is 100 mm, the scan plan 1 is selected as a candidate. That is, the scan plan 1 which is the scan plan of the head is selected from the current top position.

  Even when the same portion is imaged, the top plate position may differ depending on the orientation of the subject P on the top plate 33 and the physique of the subject P. The processing circuit 44 may select a scan plan candidate based on at least one of the information indicating the orientation of the subject P and the information indicating the physique of the subject P in addition to the top position. The information indicating the orientation of the subject P is information indicating the orientation of the subject P on the top plate 33. Specifically, the information indicating the orientation of the subject P includes head-first in which the head of the subject P faces the gantry 10 and foot-first in which the legs of the subject P face the gantry 10. The information indicating the physique of the subject P is various information that influences the physique of the subject P, and specifically, the weight, height, age, and sex (male / female) of the subject P. The age may be a numerical value indicating the age or a class such as a child or an adult. Further, the information indicating the physique of the subject P may be a class indicating the approximate physique of the subject P such as small size, standard size, or large size.

  For example, the processing circuit 44 corrects the current top position or the top position associated with each scan parameter of the scan plan table based on the information indicating the orientation of the subject P, and determines the corrected top position. Select a scan parameter candidate by using it. As a result, it is possible to correct the variation in the top plate position due to the difference in the orientation of the subject P. Further, the processing circuit 44 corrects the current top position or the top position associated with each scan parameter of the scan plan table based on the information indicating the physique of the subject P, and determines the corrected top position. Select a scan parameter candidate by using it. As a result, it is possible to correct variations in the top plate position due to differences in the physique of the subject P.

  When step SA2 is performed, the processing circuit 44 displays the scan plan candidates (step SA3). In step SA3, the processing circuit 44 displays the scan plan candidates selected in step SA2 on the display 42 by implementing the display control function 446.

  FIG. 8 is a diagram showing an example of the default scan plan selection screen IS1. A plurality of scan plans Pn (n is an integer) are displayed in a list on the scan plan selection screen IS1. The scan plan Pn is displayed by, for example, the name of the scan plan and the numbers and characters indicating the values of the scan parameters forming the scan plan. For example, the scan plan P2 has a name “head 2”, and scan parameters are a tube voltage “120 kV”, a tube current “400 mA”, an imaging range “100 mm”, and an FOV size “S”. The scan plan Pn is selectably displayed via the input interface 43. The scan plan selection screen IS1 is displayed before the selection of scan plan candidates in step SA3.

  FIG. 9 is a diagram showing the scan plan selection screen IS2 displayed in step SA3. In FIG. 9, it is assumed that scan plans P3 and P4 related to the imaging region “chest” are selected as candidates. As shown in FIG. 9, the scan plans P3 and P4 selected as candidates are displayed in a different mode from the other scan plans P1, P2, and P5. As a display mode, for example, the scan plans P3 and P4 selected as candidates may be displayed in a different color from the other scan plans P1, P2 and P5, may be displayed in a thick line, and may blink. May be done. In this way, the scan plans P3 and P4 selected as candidates and the other scan plans P1, P2, and P5 are displayed in different modes, so that the operator can easily recognize the candidates.

  FIG. 10 is a diagram showing another scan plan selection screen IS3 displayed in step SA3. As shown in FIG. 10, the scan plans P3 and P4 selected as candidates are displayed at the top of the screen more than the other scan plans P1, P2, and P5. According to such a display mode, the operator can easily recognize the candidates.

  Note that selection via the input interface 43 for each scan plan Pn on the scan plan selection screens of FIGS. 8, 9 and 10 is effective. When the non-candidate scan plans P1, P2, and P5 are selected, the processing circuit 44 may notify the positioning error of the patient (positioning error) via the display 42 or the speaker. As a result, it is possible to prevent an error in selecting a scan plan or an error in positioning a patient.

  FIG. 11 is a diagram showing another scan plan selection screen IS4 displayed in step SA3. As shown in FIG. 11, the scan plans P3 and P4 selected as candidates are displayed in a manner different from the other scan plans P1, P2, and P5, as in FIG. Then, the scan plans P3 and P4 selected as candidates are displayed so as to be selectable via the input interface 43 or the like, but the other scan plans P1, P2, and P5 are displayed as not selectable. In other words, when the candidate is selected in step SA2, the processing circuit 44 sets the scan plans P1, P2, and P5 that have not been selected as candidates from selectable to unselectable. In this way, by displaying the non-candidate scan plans P1, P2, and P5 in an unselectable manner, it is possible to prevent the operator from selecting a non-candidate.

  FIG. 12 is a diagram showing another scan plan selection screen IS5 displayed in step SA3. As shown in FIG. 12, the candidate scan plans P3 and P4 are displayed, and the non-candidate scan plans P1, P2, and P5 are not displayed. In this way, by displaying only the candidate scan plans P3 and P4 in a limited manner, the operator can recognize only the candidates.

  When step SA3 is performed, the processing circuit 44 waits until one scan plan is selected from the candidate scan plans (step SA4). For example, the operator selects, via the input interface 43, an arbitrary scan plan to be used for imaging from the candidate scan plans displayed in step SA3. When the candidate scan plan is not selected (step SA4: NO), the processing circuit 44 returns to step SA1 again and repeats steps SA1, SA2, SA3 and SA4. Steps SA1, SA2, SA3, and SA4 are repeatedly performed during the period during which the patient position setup of FIG. 3 is being performed, in other words, during the period from patient switching (step S1) to imaging (step S8). It is expected that the scan plan will not be selected before or during the movement of the top plate 33. During this period, the candidate scan plan is changed in real time according to the changing top plate position. The scan plan selected in step SA4 is actually the top plate position after the top plate 33 has been moved. For example, when the first photographing is scano photographing, the top plate 33 is arranged so that the top plate position coincides with one end (starting end) of both ends of the scanning range of the scano photographing in the Z-axis direction. In this case, the processing circuit 44 selects a scan plan candidate suitable for the top plate position regarding the start end of the scano imaging.

  When one scan plan is selected in step SA4 (step SA4: YES), the processing circuit 44 ends the scan plan selecting process shown in FIG.

  As described above, in the scan plan selection processing, the processing circuit 44 compares the current top position with the scan plan table in which the combination of the scan plan actually adopted in the past and the top position is registered. Then, the scan plan candidates are presented to the operator. By generating the scan plan table for each medical facility such as a hospital, it is possible to present an appropriate candidate regardless of the difference in the imaging policy for each medical facility.

  FIG. 13 and FIG. 14 are diagrams schematically showing the difference in the top plate position during head imaging, which is caused by the difference in the imaging policy between medical facilities. FIG. 13 shows a top plate position at the time of head imaging in a medical facility where the luggage is not placed on the top plate, and FIG. 14 shows a top plate position at the time of head imaging in a medical facility where the luggage is placed on the top plate. . As shown in FIG. 14, the top plate may be used as a storage space for therapeutic drugs, gauze, and the like. At this time, even if the imaged parts are the same, there will be a difference in the position of the top depending on whether or not the luggage is placed on the top. The scan plan table is created for each medical facility, and the combination of the scan plan and the top plate position actually adopted in the medical facility in the past is registered. By using such a scan plan table, the processing circuit 44 can select and present a scan plan considering the imaging policy of each medical facility.

(Modification 1)
The process flow shown in FIG. 6 is an example, and various changes can be made. For example, in the above embodiments, the scan plan candidates are selected and presented. However, the present embodiment is not limited to this. The processing circuit 44 according to the first modification may automatically select one scan plan.

  FIG. 15 is a diagram showing the flow from the selection of the scan plan to the imaging by the processing circuit 44 according to the first modification of the present embodiment. The process shown in FIG. 15 is another example of steps S4, S5, S6, S7 and S8 shown in FIG. Step SB1 shown in FIG. 15 is started in parallel with step S4 shown in FIG.

  As shown in FIG. 15, the processing circuit 44 acquires the information on the current top plate position by implementing the information acquisition function 444 (step SB1). In step SB1, the processing circuit 44 acquires information about the position of the tabletop automatically or after receiving an instruction from the operator via the input interface 43, for example, after the movement of the tabletop 33 is completed.

  When step SB1 is performed, the processing circuit 44 realizes the scan planning function 445 and selects one scan plan based on the current top position (step SB2). In step SB2, the processing circuit 44 first selects a scan plan candidate from the current top plate position using the scan plan table, as in step SA2 of FIG. Next, the processing circuit 44 calculates the prediction execution probability for each candidate. The predicted execution probability is the probability that the scan plan is predicted to be executed. The predicted execution probability is calculated, for example, based on the number of executions and the number of presentations associated with each scan plan in the scan plan table. The number of executions is the number of times the scan plan is actually executed. The number of presentations is the number of times the scan plan is selected as a candidate. The ratio of the number of executions to the number of presentations is defined as the predicted execution probability. The predicted execution probability may be calculated by another method. Then, the processing circuit 44 selects one scan plan having the highest prediction execution probability.

  When step SB2 is performed, the processing circuit 44 determines whether or not the predicted execution probability of the one scan plan selected in step SB2 exceeds the threshold value by implementing the scan planning function 445 (step SB3). The threshold may be set to any value. When it is determined that the predicted execution probability of one scan plan is less than or equal to the threshold value (step SB3: NO), the same process is performed again from the acquisition of the information regarding the top position in step SB1 and the time range in which the re-execution is permitted. Repeat at. That is, when it is determined that the predicted execution probability of one scan plan is less than or equal to the threshold value (step SB3: NO), the processing circuit 44 determines whether or not it is within the timeout time of automatic scan plan selection (step). SB4). The timeout time may be set, for example, within 1 minute from the start of the process of FIG. Alternatively, the processing circuit 44 may count the number of times of re-execution and compare the number of times of re-execution with a threshold value (for example, three times) that is a timeout time. When the processing circuit 44 determines that it is within the timeout time (step SB4: YES), it repeats steps SB1 to SB3. When it is determined that it is not within the timeout time (step SB4: NO), that is, when the scan plan having the predicted execution probability exceeding the threshold value is not selected within the timeout time (step SB3: NO), the processing circuit 44 Since it is necessary to select the scan plan according to the operator's judgment, the process proceeds to step SA1 shown in FIG.

  When it is determined that the predicted execution probability of one scan plan exceeds the threshold value (step SB3: YES), the processing circuit 44 starts the preparation for photographing by realizing the photographing control function 441 (step SB5). In preparation for imaging, the rotating frame 13 is rotated and the X-ray tube 11 is preheated. More specifically, the processing circuit 44 instructs the control device 15 to start rotation of the rotary frame 13 and preheating of the X-ray tube 11. Upon receiving the start command, the control device 15 rotates the rotating frame 13 at a predetermined speed. The predetermined speed may be the rotation speed corresponding to the scan plan selected in step SB2, or is lower than the rotation speed corresponding to the scan plan selected in step SB2 in order to cope with a change in the rotation speed by the operator. It may be speed. In parallel with the rotation of the rotary frame 13, the control device 15 supplies a current for preheating to the cathode of the X-ray tube 11. Thus, the X-ray tube 11 can immediately shift to a state in which X-rays can be emitted. The preheating of the X-ray tube 11 may be performed by the control of the processing circuit 44 instead of the control of the control device 15. Further, as a preparation for shooting, the processing circuit 44 may delete or move the data stored in the memory 41 in order to secure a storage area for projection data in the memory 41.

  When step SB5 is performed, the processing circuit 44 waits for the completion of preparation for photographing (step SB6). When the preparation for shooting is completed (step SB6: YES), the processing circuit 44 determines whether or not a shooting start instruction has been issued (step SB7). For example, the processing circuit 44 receives a shooting start instruction after starting the shooting preparation. The shooting start instruction is given by the operator via the input interface 43.

  When the imaging start instruction is issued (step SB7: YES), the processing circuit 44 implements the imaging control function 441 to perform X-ray CT imaging according to the scan plan selected in step SB2 (step SB8). The processing circuit 44 controls the gantry 10 by the imaging control function 441 to execute X-ray CT imaging. The gantry 10 irradiates X-rays from the X-ray tube 11 and detects X-rays by the X-ray detector 12 while rotating the rotating frame 13, and collects projection data regarding the patient for each view via the DAS 18. . The processing circuit 44 of the console 40 reconstructs a CT image based on the projection data by implementing the reconstruction function 442. The CT image is displayed on the display 42 or the like and is used for image interpretation or the like by the operator or the like.

  As described above, the processing from the selection of the scan plan to the imaging by the processing circuit 44 according to the first modification is completed.

  Note that the flow of processing illustrated in FIG. 15 is an example, and the present invention is not limited to this. For example, the processing circuit 44 may automatically execute the processing after the preparation for imaging (step SB5) when the operator selects one scan plan.

  As described above, according to the first modification, it is possible to automatically select one scan plan that matches the current top position. According to this configuration, the operator does not need to return to the operation room and select the scan plan after performing the patient position setup in the examination room. Further, according to the first modification, the gantry 10 prepares for imaging in accordance with the selected scan plan when the scan plan is selected. Therefore, the processing circuit 44 does not need to wait for the operator's instruction to set up the apparatus. Further, as an example, as shown in FIG. 15, the gantry 10 automatically starts shooting after the preparation is completed when a shooting start instruction is issued during the preparation for shooting. Therefore, the workflow of CT examination is improved.

(Modification 2)
In the above embodiment, the scan plan table is such that the top plate position is associated with each of the plurality of scan parameters. However, the present embodiment is not limited to this. In the scan plan table according to the second modification, each of the plurality of scan parameters is associated with not only the top position, but also information about a factor affecting the top position (hereinafter, referred to as an influencing factor).

  As the influencing factors, the gantry tilt angle, the horizontal position of the top plate, the vertical position of the top plate, the presence / absence of operation of the pedestal operation button, the presence / absence of an electrocardiographic waveform input, the presence / absence of a respiratory trigger input, and the presence / absence of injector connection are used. Since the gantry 10 is tilted in the head imaging and the swallowing imaging, it is possible to determine whether the head imaging or the swallowing imaging is performed based on the information about the gantry tilt angle. As for the information regarding the vertical position of the top plate, head imaging or abdominal imaging can be determined depending on the difference in body thickness of the subject P. The information on the left and right position of the tabletop can be used to determine whether the image is a target organ or a lower limb image that is a specific organ such as the heart, which is not on the patient midline. Based on the information regarding the presence / absence of operation of the gantry operation button, the orientation of the patient lying on the top plate 33 can be determined. The gantry 10 is provided with switches for operating the top plate 33 on both the side of the bed 30 that faces the base 31 and the side that does not face the base 31. For example, if the switch on the side not facing the base 31 is operated, it can be determined that the patient is lying on the top plate 33 with head first. The presence / absence of electrocardiographic waveform input, the presence / absence of respiratory trigger input, and the presence / absence of injector connection are related to the presence / absence of an option connected to the system. When electrocardiographic waveform input, respiratory trigger input and injector connection are required, it is useful for selecting a specific scan plan to utilize them.

  The processing circuit 44 acquires the current top position and the current influencing factor, and uses the scan plan table to select a scan plan candidate from the combination of the current top position and the current influencing factor. At this time, the processing circuit 44 may select the scan plan associated with the combination of the top position and the influencing factor, which completely matches the combination of the current top position and the current influencing factor. Further, the processing circuit 44 may select a scan plan from the scan plan table based on a composite evaluation function based on the combination of the current top position and the current influencing factor.

  In addition, the processing circuit 44 may use this information to select a scan plan when the body position information and the imaged region information are known in advance when the patient name is registered. When the breathing exercise or the like is performed first, the processing circuit 44 may select the scan plan by also using the information on the language type and the breathing exercise content. In particular, when connected to a patient reservation system or the like, the processing circuit 44 may select the scan plan based on the information registered in advance.

  According to the second modification, it is possible to more accurately select and present a scan plan candidate by using a factor that affects the top position in addition to the top position.

(Modification 3)
In the above embodiment, the scan plan table is created and used for each medical facility. The X-ray CT system used in another medical facility and the X-ray CT system of its own medical facility have different mechanical restrictions on the movement range of the bed 33, the gantry 10, etc. due to the difference in the geometry of the device. There are cases. In this case, the top plate position may be different even when the same imaging region is imaged in its own medical facility and another medical facility. The processing circuit 44 according to the third modification calibrates the scan plan table created in another medical facility by using the calibration function 447 in order to use the scan plan table in its own medical facility. The X-ray CT system 1 according to Modification 3 will be described below.

  A scan plan table created in another medical facility is stored in the memory 41 according to the third modification. The processing circuit 44 calibrates the scan plan table on the basis of mechanical constraints on the movement range of the gantry 10 or the bed 30 of the own device, for example, movement of the top plate of an X-ray CT system used in another medical facility. The top position associated with each of the plurality of scan parameters is calibrated according to the ratio between the range and the moving range of the top 33 of the X-ray CT system 1 used in the medical facility. As a result, since the scan plan table created in another medical facility can be used in its own medical facility, it is possible to reduce the trouble of creating the scan plan table.

(Modification 4)
In the above-described embodiment, the processing circuit 44 is supposed to acquire, as the position information, the information related to the position of the tabletop based on the output from the rotary encoder. However, the present embodiment is not limited to this. The processing circuit 44 according to the modified example 4 acquires the position information by the image analysis of the optical camera.

  For example, the optical camera is installed at a position where the reference point of the top plate 33 is included in the imaging field of view, such as the pedestal 10 or the ceiling or wall surface of the examination room. The reference point of the top plate 33 means an end portion of the top plate 33 or a mark provided on the top plate 33. The reference point of the top plate is provided at a position where the optical camera can capture an image even when the subject P is placed on the top plate 33. The optical camera generates an optical image in which the reference point of the top plate 33 is drawn. The optical image is transmitted to the processing circuit 44. The processing circuit 44 performs image processing on the optical image to specify the position coordinate of the reference point of the top plate 33 in the optical image, and the specified position coordinate is determined based on the installation position and the installation angle of the optical camera. Convert to position coordinates in the coordinate system. As the image processing, for example, threshold processing is used. The position coordinates in the coordinate system of the examination room are used as the top plate position.

  In the above embodiment, the position information is the top position. However, the present embodiment is not limited to this. The position information may be any information as long as it is information that correlates with the positional relationship between the subject P and the gantry 10. For example, the position information may be information related to the position of the subject P (hereinafter referred to as the subject position). The subject position may also be specified by performing image processing on the optical image.

  For example, the optical camera is installed at a position where the reference point of the subject P is included in the imaging field of view, such as the pedestal 10 or the ceiling or wall surface of the examination room. The reference point of the subject P means the crown of the subject P, other characteristic points, and a mark attached to the subject P. An optical image in which a reference point of the subject P is drawn is generated by the optical camera. The optical image is transmitted to the processing circuit 44. The processing circuit 44 performs image processing on the optical image to specify the position coordinates of the reference point of the subject P in the optical image, and the specified position coordinates of the inspection room based on the installation position and the installation angle of the optical camera. Convert to position coordinates in the coordinate system. As the image processing, for example, threshold processing is used. The position coordinate in the coordinate system of the examination room is used as the subject position.

  As described above, according to the fourth modification, it is possible to obtain the position information correlated with the positional relationship between the subject P and the gantry 10 by using the optical camera.

(Modification 5)
In the above embodiment, the top plate 33 of the bed 30 is moved along the Z axis or the like in order to align the subject P with the X-ray path of the gantry 10. However, the present embodiment is not limited to this. For example, the base 31 of the bed 30 may be provided so as to be movable along the Z axis or the like. The base 31 movable along the Z axis or the like may be realized by, for example, a self-propelled base 31 having wheels, or along a rail provided on the floor along the Z axis or the like. It may be realized by the moving base 31.

(Modification 6)
In the above embodiment, the top plate 33 of the bed 30 is moved along the Z axis or the like in order to align the subject P with the X-ray path of the gantry 10. However, the present embodiment is not limited to this. For example, the gantry 10 may be provided so as to be movable along the Z axis along a rail provided on the floor surface. Further, the X-ray CT system may be a composite system having an X-ray CT apparatus and an X-ray diagnostic apparatus that share one bed. Since the position of the gantry 10 correlates with the positional relationship between the subject P and the gantry 10, the processing circuit 44 according to the modified example 5 may acquire the position information of the gantry 10 as the position information.

(Modification 7)
In the above embodiment, the top plate 33 of the bed 30 is moved along the Z axis or the like in order to align the subject P with the X-ray path of the gantry 10. However, the present embodiment is not limited to this. For example, the X-ray CT system 1 may be an upright type having a column that moves the gantry 10 up and down along the Y axis in a posture in which the rotation axis is parallel to the Y axis. In this case, since the position of the gantry 10 correlates with the positional relationship between the subject P and the gantry 10, the processing circuit 44 may acquire the position information of the gantry 10 as the position information.

(Other examples)
The console 40 does not necessarily have to be installed in the operation room. For example, the console 40 may be installed in the same room as the gantry 10 and the bed 30. Further, the console 40 may be incorporated in the gantry 10. Further, some elements such as the memory 41 of the console 40 are physically independent from the console 40 and may be mounted on hardware connected via a network.

  Further, in the above embodiment, the X-ray CT system 1 is assumed to be the so-called third generation. That is, the X-ray CT system 1 is a rotation / rotate type in which the X-ray tube and the X-ray detector are integrally rotated around the rotation axis. However, the X-ray CT system 1 according to this embodiment is not limited to that. For example, the X-ray CT system 1 may be a fixed / rotary type in which a large number of X-ray detection elements arranged in a ring shape are fixed and only the X-ray tube rotates around the rotation axis. . Further, in the X-ray CT system 1, a large number of X-ray detection elements arranged in a ring shape are fixed, an anode is arranged in a ring shape, and the fifth generation in which an electron beam is irradiated to the anode in a ring shape by electromagnetic deflection. Good.

  In the above description, the X-ray CT system 1 according to the present embodiment is described as a one-tube type, but it is also applicable to a so-called multi-tube type.

(Summary)
According to at least one embodiment described above, the medical image diagnostic system according to this embodiment includes a memory 41 and a processing circuit 44. The memory 41 stores a plurality of scan parameter sets (scan plans). Each of the plurality of scan parameter sets relates to a combination of a plurality of types of scan parameter values. The processing circuit 44 selects one of a plurality of scan plans based on the positional information correlated with the positional relationship between the subject P and the gantry 10 that is acquired along with the movement of the subject P or the gantry 10 that scans the subject P. Select at least one scan plan from.

  According to the above configuration, it is possible to automatically select and set the scan plan at the start of shooting preparation based on the position information. As a result, as shown in FIG. 3, the workflow of CT examination is improved and the burden on the operator is reduced. As a result, the operator can concentrate on other tasks such as dealing with the subject P.

  According to at least one embodiment described above, it is possible to reduce the preparation burden on the operator for medical imaging.

  The word "processor" used in the above description is, for example, a CPU, a GPU, or an application specific integrated circuit (ASIC), a programmable logic device (for example, a simple programmable logic device (Simple Programmable Logic Device). : SPLD), a complex programmable logic device (CPLD), and a field programmable gate array (FPGA)). The processor realizes the function by reading and executing the program stored in the memory circuit. Instead of storing the program in the memory circuit, the program may be directly incorporated in the circuit of the processor. In this case, the processor realizes the function by reading and executing the program incorporated in the circuit. Further, instead of executing the program, a function corresponding to the program may be realized by a combination of logic circuits. It should be noted that each processor of the present embodiment is not limited to the case where each processor is configured as a single circuit, and a plurality of independent circuits may be combined and configured as one processor to realize its function. Good. Further, the plurality of constituent elements in FIGS. 1 and 2 may be integrated into one processor to realize its function.

  Although some embodiments of the present invention have been described, these embodiments are presented as examples 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 invention described in the claims and the equivalents thereof as well as included in the scope and the gist of the invention.

1 X-ray CT system 10 Stand 11 X-ray tube 12 X-ray detector 13 Rotating frame 14 X-ray high-voltage device 15 Controller 16 Wedge 17 Collimator 18 Data acquisition circuit (DAS: Data Acquisition System)
19 opening 23 gantry body 25 fixed part 30 bed 31 base 32 support frame 33 top plate 34 bed drive device 40 console 41 memory 42 display 43 input interface 44 processing circuit 441 imaging control function 442 reconstruction processing function 443 image processing function 444 Information acquisition function 445 Scan planning function 446 Display control function 447 Calibration function

Claims (15)

A storage unit that stores a plurality of scan parameter sets,
At least one of the plurality of scan parameter sets is based on position information that is acquired with the movement of the subject or a scanning unit that scans the subject and that is correlated with the positional relationship between the subject and the scanning unit. A selection section for selecting one scan parameter set,
A medical image diagnostic system comprising:   The medical image diagnostic system according to claim 1, wherein the position information includes information about a position of a top plate on which the subject is placed, a position of the scanning unit, or a position of the subject.   The selection unit selects the at least one scan parameter set based on at least one of information indicating the orientation of the subject and information indicating the physique of the subject in addition to the position information. 1. The medical image diagnostic system according to 1.   The medical image diagnostic system according to claim 1, further comprising an acquisition unit that automatically acquires the position information during or after the movement of the subject or the scanning unit.   The medical image diagnostic system according to claim 4, wherein the acquisition unit acquires the position information during a period from a patient switching instruction to the start of a positioning scan. Further comprising the scanning unit,
The scan unit starts preparation for imaging according to the at least one scan parameter set, when the at least one scan parameter set is selected.
The medical image diagnostic system according to claim 1. The scanning unit is
The frame provided with the X-ray tube and the X-ray detector has a pedestal that rotatably supports around the opening,
Upon the selection of the at least one scan parameter set, rotation of the frame is started as the preparation.
The medical image diagnostic system according to claim 6.   7. The medical image diagnostic system according to claim 6, wherein the scanning unit automatically starts imaging after completion of the preparation when a start instruction is given during the preparation period.   A display control unit that displays the at least one scan parameter set on a display unit and does not display a scan parameter set different from the at least one scan parameter set of the plurality of scan parameter sets on the display unit; The medical image diagnostic system according to claim 1.   The at least one scan parameter set is displayed on the display unit in the first display mode, and the scan parameter set different from the at least one scan parameter set is displayed in the second display mode different from the first display mode. The medical image diagnostic system according to claim 1, further comprising a display control unit for displaying on the display unit.   The medical image diagnostic system according to claim 1, wherein the selection unit selects the at least one scan parameter set based on the position information at the time of starting the positioning scan by the scanning unit. The storage unit associates, for each of the plurality of scan parameter sets, positional information when the scan parameter set was selected in the past,
The selecting unit selects the at least one scan parameter set based on a difference between the position information and past position information associated with each of the plurality of scan parameter sets.
The medical image diagnostic system according to claim 1. The scanning unit is
Selecting a first scan parameter set as the at least one scan parameter set from the plurality of scan parameter sets;
If a predicted execution probability of the first scan parameter set is higher than a threshold value, a scan is executed according to the first scan parameter set,
The medical image diagnostic system according to claim 1.   In addition to the position information, the selection unit includes a gantry tilt angle, a top / bottom position, a top / bottom position, presence / absence of an operation button of the pedestal, presence / absence of electrocardiographic waveform input, presence / absence of respiratory trigger input, and presence / absence of injector connection. The medical image diagnostic system according to claim 1, wherein the at least one scan parameter set is selected by using at least one of the plurality of scan parameter sets.   The medical image diagnostic system according to claim 1, wherein the calibration unit calibrates position information associated with each of the plurality of scan parameter sets based on a mechanical constraint regarding a moving range of the bed of the apparatus or the scanning unit.