JP2023074336A - Medical image diagnostic apparatus and bed apparatus - Google Patents

Abstract

To measure the weight of a subject by a bed apparatus.SOLUTION: A medical image diagnostic apparatus according to an embodiment comprises: a top plate; a lifting mechanism; a power unit; a power control unit; and an estimation unit. A subject is placed on the top plate. The lifting mechanism lifts or lowers the top plate. The power unit gives the power of holding or lifting/lowering the top plate to the lifting mechanism. The power control unit controls the power unit such that the top plate is lowered according to the weight of the subject placed on the top plate. The estimation unit estimates an estimated weight being the weight of the subject on the basis of a displacement amount of a height position of the top plate under the control.SELECTED DRAWING: Figure 2

Description

The embodiments disclosed in the specification and drawings relate to a medical imaging diagnostic apparatus and a couch apparatus.

A medical image diagnostic apparatus obtains a medical image by photographing the inside of a subject, thereby providing a user with useful information for diagnosis and treatment. 2. Description of the Related Art Some imaging conditions in a medical image diagnostic apparatus are determined based on the weight of a subject. For example, the amount of contrast medium administered to the subject, the dose of X-rays, and the like are known. As means for obtaining the weight of the subject, there are the use of a weight scale separate from the medical image diagnostic apparatus and self-reporting of the subject.

JP 2012-125305 A JP 2010-167189 A

One of the problems to be solved by the embodiments disclosed in the specification and drawings is to measure the weight of a subject using a couch apparatus. However, the problems to be solved by the embodiments disclosed in this specification and drawings are not limited to the above problems. Each problem corresponding to each configuration shown in the embodiment described later can also be positioned as another problem.

A medical image diagnostic apparatus according to the present embodiment includes a tabletop, an elevating mechanism, a power unit, a power control unit, and an estimation unit. A subject is placed on the top plate. The elevating mechanism elevates the top board. The power unit provides power for holding or raising/lowering the top plate to the lifting/lowering mechanism. The power control unit controls the power unit so that the top plate is lowered according to the weight of the subject placed on the top plate. The estimation unit estimates an estimated weight, which is the weight of the subject, based on the amount of displacement of the height position of the tabletop under the control.

1 is a block diagram showing an example of the configuration of an X-ray CT apparatus according to a first embodiment; FIG. FIG. 2 is a block diagram showing an example of the configuration of a control device according to the first embodiment; FIG. 3 is a block diagram showing an example of the configuration of the bed device according to the first embodiment; 4 is a block diagram showing an example of a configuration of a support frame according to the first embodiment; FIG. FIG. 5 is a schematic diagram for explaining an example of a position correction amount at the time of photographing according to the first embodiment; 6 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the first embodiment; FIG. FIG. 7 is a graph showing an example of temporal changes in the height position of the tabletop according to the first embodiment; 8 is a diagram for explaining an example of a lookup table according to the first embodiment; FIG. FIG. 9 is a block diagram showing an example of the configuration of a control device according to a second embodiment; 10 is a block diagram showing an example of a configuration of a bed device according to a second embodiment; FIG. 11 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the second embodiment; FIG. FIG. 12 is a graph showing an example of temporal changes in the height position of the table top and the output of the bed driving device according to the second embodiment; FIG. 13 is a diagram for explaining an example of a lookup table according to the second embodiment; 14 is a flowchart showing an example of processing executed by a processing circuit of the X-ray CT apparatus according to the third embodiment; FIG. 15 is a graph showing an example of temporal changes in the height position of the tabletop and the output of the bed driving device according to the third embodiment; FIG. 16 is a block diagram showing an example of a configuration of a bed device according to a fourth embodiment; FIG. FIG. 17 is a block diagram showing an example of a configuration of a bed device according to a fifth embodiment;

A medical image diagnostic apparatus and a bed apparatus according to each embodiment will be described below with reference to the drawings.

Medical diagnostic imaging devices include, for example, X-ray CT (Computed Tomography) devices, MRI (Magnetic Resonance Imaging) devices, PET (Positron Emission Tomography) devices, and SPECT (Single Photon emission Computed Tomography). hy) is a single modality such as a device . Alternatively, the medical diagnostic imaging apparatus may be a composite modality such as a PET-CT apparatus, a SPECT-CT apparatus, and a PET-MR apparatus. In the following description, the medical image diagnostic apparatus according to each embodiment is described as an X-ray CT apparatus, but each embodiment is not limited to an X-ray CT apparatus, and various medical image diagnostic apparatuses described above can be used. A similar implementation is possible.

(First embodiment)
A first embodiment will be described. The bed device 30 according to the present embodiment is provided between a top plate 31, which is a plate on which a subject is placed, and a floor surface on which the top plate 31 and the bed device 30 are installed. and an elastic body 80 that is elastically deformed. In the present embodiment, when the subject P is placed on the top plate 31 held by the elastic force generated in the elastically deformed elastic body 80, the top plate 31 is held until the gravity acting on the subject P and the elastic force generated in the elastic body 80 are balanced. The plate 31 is controlled to descend. By measuring the amount of displacement of the height position of the top plate 31 before the control and the height position of the top plate 31 after being balanced, and referring to a lookup table prepared in advance using the measured displacement amount, the top can be adjusted. An example of estimating the weight of the subject P placed on the plate 31 will be described. A more detailed description of the bed device 30, the top plate 31, and the elastic body 80 will be given later.

FIG. 1 is a block diagram showing an example configuration of an X-ray CT apparatus 1 according to the first embodiment. The X-ray CT apparatus 1 has a gantry device 10, a bed device 30, and a console device 40, for example. For convenience of explanation, FIG. 1 shows both a view of the gantry device 10 viewed from the Z-axis direction and a view of the gantry device 10 viewed from the X-axis direction. In this embodiment, the rotation axis of the rotating frame 17 in the non-tilt state or the longitudinal direction of the top plate 31 of the bed apparatus 30 is the Z-axis direction, and the axis perpendicular to the Z-axis direction and horizontal to the floor surface is X A direction orthogonal to the axial direction and the Z-axis direction and perpendicular to the floor surface is defined as the Y-axis direction.

The gantry device 10 includes an X-ray tube 11, a wedge 12, a collimator 13, an X-ray high voltage device 14, an X-ray detector 15, a DAS (Data Acquisition System) 16, a rotating frame 17, and a control device. 18.

The X-ray tube 11 generates X-rays by applying a high voltage from the X-ray high voltage device 14 and irradiating thermal electrons from a cathode (filament) toward an anode (target). X-ray tube 11 includes a vacuum tube. For example, the X-ray tube 11 is a rotating anode type X-ray tube that generates X-rays by irradiating a rotating anode with thermal electrons.

The wedge 12 is a filter for adjusting the dose of X-rays irradiated from the X-ray tube 11 to the subject P. As shown in FIG. Specifically, the wedge 12 transmits and attenuates the X-rays emitted from the X-ray tube 11 so that the X-rays emitted from the X-ray tube 11 to the subject P have a predetermined distribution. is a filter. For example, the wedge 12 may be a wedge filter or a bow-tie filter, which is a filter machined from aluminum to have a predetermined target angle and thickness.

The collimator 13 is a lead plate or the like for narrowing down the irradiation range of the X-rays transmitted through the wedge 12, and a slit is formed by combining a plurality of lead plates or the like. Note that the collimator 13 may also be called an X-ray diaphragm.

The X-ray high-voltage device 14 has electric circuits such as a transformer and a rectifier, and has a high-voltage generation device having a function of generating a high voltage to be applied to the X-ray tube 11. an X-ray control device for controlling an output voltage according to the amount of X-rays to be applied. The high voltage generator may be of a transformer type or an inverter type. Note that the X-ray high-voltage device 14 may be provided on a rotating frame 17 to be described later, or may be provided on a fixed frame (not shown) side of the gantry device 10 . Note that the fixed frame is a frame that rotatably supports the rotating frame 17 . Also, the X-ray high voltage device 14 is an example of an X-ray high voltage section.

The X-ray detector 15 detects X-rays emitted from the X-ray tube 11 and passing through the subject P, and outputs an electrical signal corresponding to the X-ray dose to the DAS 16 . The X-ray detector 15 has, for example, a plurality of X-ray detection element arrays in which a plurality of X-ray detection elements are arranged in the channel direction along one circular arc centered on the focal point of the X-ray tube 11 . The X-ray detector 15 has, for example, a structure in which a plurality of X-ray detection element arrays each having a plurality of X-ray detection elements arranged in the channel direction are arranged in the slice direction (column direction, row direction). Also, the X-ray detector 15 is, for example, an indirect conversion type detector having a grid, a scintillator array, and a photosensor array.

The scintillator array has a plurality of scintillators, and each scintillator has a scintillator crystal that outputs a photon amount of light corresponding to the amount of incident X-rays.

The grid is arranged on the surface of the scintillator array on the X-ray incident side and has an X-ray shielding plate that absorbs scattered X-rays. Note that the grid may also be called a collimator (one-dimensional collimator or two-dimensional collimator).

The photosensor array has a function of converting the amount of light from the scintillator into an electrical signal, and includes photosensors such as photodiodes and photomultiplier tubes, for example.

The X-ray detector 15 may be a direct conversion type detector having a semiconductor element that converts incident X-rays into electrical signals. Also, the X-ray detector 15 is an example of an X-ray detection unit.

The DAS 16 has an amplifier that amplifies the electrical signal output from each X-ray detection element of the X-ray detector 15 and an A/D converter that converts the electrical signal into a digital signal. to generate Detection data generated by the DAS 16 is transferred to the console device 40 . Also, the DAS 16 is an example of a data collection unit.

The rotating frame 17 is an annular frame that supports the X-ray tube 11 and the X-ray detector 15 so as to face each other and rotates the X-ray tube 11 and the X-ray detector 15 by means of a control device 18, which will be described later. In addition to the X-ray tube 11 and the X-ray detector 15, the rotating frame 17 further includes an X-ray high voltage device 14 and a DAS 16 to support them. Additionally, the rotating frame 17 can also support various configurations not shown in FIG. Below, in the gantry device 10, the portion that rotates together with the rotating frame 17 and the rotating frame 17 are also referred to as rotating portions.

The detection data generated by the DAS 16 is transmitted by optical communication from a transmitter having a light emitting diode (LED) provided on the rotating frame 17 to a photodiode provided on the non-rotating portion of the gantry device 10. It is transmitted to the receiver and transferred to the console device 40, which will be described later. Contactless data transfer may be employed. Also, the rotating frame 17 is an example of a rotating portion.

The configuration of the control device 18 will be described with reference to FIG. FIG. 2 is a block diagram showing an example of the configuration of the control device 18 according to this embodiment.

The control device 18 has, for example, a memory 181, a driving mechanism (not shown) such as a motor and an actuator, and a processing circuit 182 having a CPU (Central Processing Unit) and the like. The control device 18 has a function of receiving input signals from an input interface 43 and a processing circuit 50 attached to the console device 40 or the gantry device 10 and controlling the operations of the gantry device 10 and the bed device 30 . For example, the control device 18 receives an input signal and performs control to rotate the rotating frame 17 , control to tilt the gantry device 10 , and control to operate the bed device 30 and the tabletop 31 . The control for tilting the gantry device 10 is performed by the control device 18 rotating the frame about an axis parallel to the X-axis direction based on inclination angle (tilt angle) information input by the input interface 43 attached to the gantry device 10 . It is realized by rotating 17. Note that the control device 18 may be provided in the gantry device 10 or may be provided in the console device 40 .

The memory 181 is implemented by, for example, a RAM (Random Access Memory), a semiconductor memory device such as a flash memory, a hard disk, an optical disk, or the like. The memory 181 stores, for example, a contact position H1 (to be described later), a lower limit position H4 that is the lower limit of the height position of the top plate 31, weight data associated with accessories to be described later, and data on the top plate 31 (to be described later). A lookup table used for estimating the weight of the placed subject P, a lookup table and a function that associate the weight of the top plate 31, the weight of the subject P and the appropriate value of the contrast agent, and the subject Data on the cross-sectional shape of the subject P according to the weight of the subject P, data on the imaging range (Field Of View: FOV) used when imaging the positioning image and setting imaging conditions for the main imaging, and the like are stored. These data may be stored in an external memory with which controller 18 can communicate, rather than (or in addition to) memory 181 . The external memory is, for example, memory 41 .

The processing circuit 182 controls operations of the gantry device 10 and the bed device 30 . A power control function 182a, a braking control function 182b, a necessity determination function 182c, a height acquisition function 182d, an accessory weight acquisition function 182e, an estimation function 182f, a calculation function 182g, a shape estimation function 182h, and a position correction function 182i of the processing circuit 182. , are recorded in the memory 181 in the form of a computer-executable program. The processing circuit 182 reads the programs from the memory 181 and executes them to implement functions corresponding to each program. In other words, the processing circuit 182 with each program read has each function shown in the processing circuit 182 of FIG. The processing circuitry 182 is implemented by, for example, a processor. Also, the processing circuit 182 is an example of a processing unit.

2, the processing circuit 182 in a single processor includes a power control function 182a, a braking control function 182b, a necessity determination function 182c, a height acquisition function 182d, an accessory weight acquisition function 182e, Processing functions performed by the estimation function 182f, the calculation function 182g, the shape estimation function 182h, and the position correction function 182i are realized. However, the processing circuit 182 may be configured by combining a plurality of independent processors, and each function of the processing circuit 182 may be realized by each processor executing a program. 2, the single memory 181 stores a program corresponding to each processing function of the processing circuit 182, but a plurality of memories 181 are arranged in a distributed manner so that the processing circuit 182 can be individually stored. A configuration in which the corresponding program is read from the memory 181 may be employed.

The term "processor" used in the above description includes, for example, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), or an application specific integrated circuit (ASIC), a programmable logic device (e.g. , Simple Programmable Logic Device (SPLD), Complex Programmable Logic Device (CPLD), or Field Programmable Gate Array (FPGA)). When the processor is, for example, a CPU, the processor reads out and executes programs stored in the memory 181 to achieve its functions. On the other hand, if the processor is an ASIC, instead of storing the program in memory 181, the functionality is directly embedded as a logic circuit within the circuitry of the processor.

The power control function 182a controls the operation of raising and lowering the tabletop 31 by outputting an instruction signal to the bed driving device 34, which will be described later. The details of the control of the bed driving device 34 by the power control function 182a will be described later. Also, the power control function 182a is an example of a power control unit.

The braking control function 182b outputs an instruction signal to the braking device 38, which will be described later, to turn on/off the braking device 38. FIG. Details of the control on the braking device 38 by the braking control function 182b will be described later. Also, the braking control function 182b is an example of a braking control section.

The necessity determination function 182c determines whether or not to execute the weight estimation of the subject P based on an input operation received from the user via the input interface 43, which will be described later. Note that the necessity determination function 182c is an example of a necessity determination unit.

For example, the necessity determination function 182c causes the display control function 56, which will be described later, to display a GUI (Graphical User Interface) screen on the display 42, which receives from the user whether or not weight estimation of the subject P is necessary. After that, the necessity determination function 182c may receive the user's determination as to whether or not weight estimation of the subject P is necessary via the GUI screen. Further, the necessity determination function 182c, for example, allows the user to input data to the subject via an input interface (such as an input interface 43 to be described later) such as buttons provided in the gantry device 10, the bed device 30, and the console device 40 to be described later. A determination as to whether or not weight estimation of P is necessary may be accepted.

Further, the necessity determination function 182c may determine whether or not to execute the weight estimation of the subject P, which will be described later, based on the information about the subject P in past examinations. The necessity determination function 182c receives, for example, information on the subject P in past examinations from a radiology information system (RIS). The information of the subject P in the past examination is, for example, the date and time of the past examination and the weight of the subject P at the time of the past examination. For example, the necessity determination function 182c determines that execution of weight estimation of the subject P is necessary when the past examination date and time is before the current examination date and time by a certain period of time. On the other hand, for example, the necessity determination function 182c determines that execution of weight estimation of the subject P is unnecessary when the past examination date and time are within a certain period of time from the current date and time. Note that the necessity determination function 182c may receive information in which the user arbitrarily sets the certain period of time, such as three months or six months, via the input interface 43, which will be described later.

The height acquisition function 182 d acquires the height position, which is the position of the top plate 31 in the Y direction, from the encoder 81 described later and outputs it to the memory 181 . Further, the height acquisition function 182d may output to the memory 181 the amount of displacement from the reference height position of the tabletop 31 . The height acquisition function 182d is an example of a height acquisition section.

The accessory weight acquisition function 182 e derives the weight of accessories placed on the top board 31 other than the subject P, and outputs the weight of the accessory to the memory 181 . Accessories include, for example, syringe pumps, drain bags, manure bags, bedside monitors, medical oxygen cylinders, backboards, infusion solutions, and trays. The accessory weight acquisition function 182e acquires an image of a range including the subject P and accessories captured by the camera 20, which will be described later, while the subject P is placed on the table top 31, for example. Thereafter, accessory weight acquisition function 182 e detects accessories from the image and reads the weight corresponding to each detected accessory from the lookup table stored in memory 181 . Then, the total weight of all the detected accessories is output to the memory 181 . Note that the user may input the weight of the accessory via the input interface 43, which will be described later. Also, the accessory weight acquisition function 182e is an example of an accessory weight acquisition unit.

The estimating function 182f estimates the weight of the subject P placed on the tabletop 31 . The estimating function 182f uses, for example, a lookup table in which the amount of displacement of the height position of the tabletop 31 stored in the memory 181 and a plurality of weight values are associated with each other. The weight (estimated weight) of the subject P is output to the memory 181 . Also, the estimation function 182f is an example of an estimation unit.

Assuming that the estimated weight obtained by the estimating function 182f does not match the actual weight of the subject P, the accessory is placed on the top board 31 after the subject P is placed on the top board 31. or a subject P to which accessories are attached may be placed on the top plate 31 .

A method for coping with this case will be described. The estimation function 182f reads from the memory 181 the total weight of accessories acquired by the accessory weight acquisition function 182e. The estimation function 182f then performs post-processing to subtract the total weight of the accessory from the estimated weight. After that, the estimation function 182f updates the estimated weight to the post-processed weight.

The calculation function 182g acquires the estimated weight from the memory 181 and calculates the appropriate amount of the contrast medium to be administered to the subject P from the estimated weight. The calculation function 182g reads, for example, a lookup table and a function that associate the estimated weight of the subject P and the appropriate contrast agent value from the memory 181, and calculates the appropriate contrast agent value according to the weight of the subject P. calculate. The calculation function 182g outputs the appropriate value to the memory 181. FIG. Also, the calculation function 182g is an example of a calculation unit.

The shape estimation function 182h acquires the estimated weight from the memory 181, acquires the height, age, and sex of the subject P from the RIS, and estimates the shape of the subject P. FIG. The estimating function 182f estimates the cross-sectional shape of the subject P by, for example, reading out the cross-sectional shape of the subject P corresponding to information combining the estimated weight, height, age, and sex of the subject P from the memory 181. . The shape estimation function 182 h outputs the cross-sectional shape (estimated cross section) to the memory 181 . Also, the shape estimation function 182h is an example of a shape estimation unit.

The position correcting function 182i acquires the estimated cross section from the memory 181 and corrects the height position of the tabletop 31 during positioning image photography and actual photography. FIG. 5 is a diagram showing an example of the position correction amount in this embodiment. In the left diagram of FIG. 5, the height position of the top plate 31 is set so that the center of gravity of the cross section of the subject P, which is prepared as the initial condition when setting the imaging conditions, and the center of gravity of the FOV coincide with each other. This is an example. The right diagram of FIG. 5 is an example in which the height position of the top plate 31 is set so that the height positions of the center of gravity of the estimated cross section and the center of gravity of the FOV match. If there is a difference in the width in the Y direction between the cross section of the subject P prepared as the initial conditions when setting the imaging conditions and the estimated cross section, the cross section of the subject P will be different if the height position of the tabletop 31 is not corrected. The height positions of the center of gravity and the center of gravity of the FOV are shifted. Therefore, the position correction function 182i calculates the position correction amount of the top plate 31 such that the height positions of the center of gravity of the estimated cross section and the center of gravity of the FOV match. After that, the position correction function 182i outputs a position correction signal for moving the height position of the table top 31 to the bed driving device 34 according to the position correction amount. Also, the position correction function 182i is an example of a position correction unit.

The camera 20 acquires images of the table 31 and the subject P placed on the table 31 . The camera 20 is provided above the top plate 31, for example. The mounting position of the camera 20 may be, for example, the side of the gantry 10 on which the bed device 30 is installed, the ceiling of the room where the X-ray CT apparatus 1 is installed, or the vicinity of the bed device 30 . Note that the camera 20 may include a plurality of cameras.

Next, the configuration of the bed device 30 will be described with reference to FIGS. 3 and 4. FIG. FIG. 3 is a schematic side view of the bed device 30 according to the present embodiment as seen from the -X direction. Note that the housing of the bed device 30 is not shown in FIG. FIG. 4 is a schematic side view of the support frame 32 according to this embodiment as seen from the +Y direction.

The bed device 30 is a device for placing and moving the subject P to be imaged. The bed device 30 includes, for example, a top board 31, a support frame 32, a support table 33, a bed driving device 34, and a sensor 35, as shown in FIG.

The top plate 31 is a plate on which the subject P is placed. The top plate 31 is provided on the upper surface of the support frame 32 . The top plate 31 is made of a material having a relatively high X-ray transmittance, such as urethane foam and carbon.

The support frame 32 is a frame-shaped frame that supports the top plate 31 so as to be slidable in the Z direction (long axis direction of the top plate 31). For example, as shown in FIG. 4, the support frame 32 has guide rails 321 that guide the top plate 31 in the Z direction and a top plate driving device (not shown) for sliding the top plate 31 . The guide rails 321 are provided on a pair of frames that are the long sides of the support frame 32 . The tabletop driving device receives an operation instruction signal from the control device 18 and realizes the sliding operation of the tabletop 31 along the guide rails 321 . The support frame 32 may be, for example, a pair of beam-shaped frames to which the guide rails 321 are attached.

The support table 33 is a support mechanism that allows the top plate 31 and the support frame 32 to move in the Y direction (vertical direction). The support base 33 has, for example, an X link 71 and a base 72 as shown in FIG.

The X-link 71 is a pair of X-shaped links that are connected to the support frame 32 and the base 72 . The X-link 71 has, for example, a movable link 711 and a fixed link 712 . The movable link 711 and the fixed link 712 are provided so as to be rotatable around the fulcrum 73 . Although only one X link 71 is shown in FIG. 3, there is another one in the +X direction. Also, the X link 71 is an example of an elevating mechanism.

Each of the movable link 711 and the fixed link 712 is formed of, for example, a pair of plate-shaped metal plates having substantially the same length. Also, the distance between the end 715 of the movable link 711 on the side of the base 72 and the fulcrum 73, the distance between the end 716 of the movable link 711 on the side of the support frame 32 and the fulcrum 73, the end of the fixed link 712 on the side of the base 72 The distance between the portion 713 and the fulcrum 73 and the distance between the end 714 of the fixed link 712 on the side of the support frame 32 and the fulcrum 73 are designed to have substantially the same length, for example. The ends 714 and 716 are examples of ends connected to the top plate, and the ends 713 and 715 are examples of ends opposite to the ends connected to the top plate.

An end portion 713 of the fixed link 712 on the side of the base 72 is fixed to the base 72 . The end portion 713 may be fixed by, for example, a fastener or the like, or may be fixed by being fitted into a recess provided in the base 72 . An end 714 of the fixed link 712 on the support frame 32 side is fixed to the support frame 32 . The end portion 714 is fixed, for example, by a fastener or the like to a first link 76 between the trochanters 74 provided on the guide rail 321 . For example, the end portion 714 may be fixed to the trochanter 74 with a fastener or the like, or may be fixed by being fitted into a recess provided in the support frame 32 .

An end portion 715 of the movable link 711 on the side of the base 72 is connected to the base 72 so as to be slidable in the Z direction. End 715 is connected to nut 37, for example. An end 716 of the movable link 711 on the side of the support frame 32 is connected to a second link 77 between rollers 75 provided on the guide rail 321 and slidable in the Z direction, for example. For example, the end portion 716 may be fixed to the trochanter 75 with a fastener or the like, or may be fixed by being fitted into a recess provided in the support frame 32 .

The bed driving device 34 is a device that outputs power to move the tabletop 31 on which the subject P is placed in the Y direction (direction perpendicular to the tabletop 31). The bed driving device 34 is, for example, a motor and an actuator. The bed driving device 34 outputs power according to a signal from the control device 18, for example. Also, the bed driving device 34 is an example of a power section.

One end of the lead screw 36 is connected to the drive shaft of the bed drive device 34, and the lead screw 36 rotates in conjunction with the rotation of the bed drive device 34 around the drive shaft. A lead screw 36 passes through a nut 37 and a braking device 38 .

The nut 37 has a through-hole formed with a thread groove that is screwed onto the thread of the lead screw 36 . The nut 37 slides in the Z direction as the lead screw 36 rotates. For example, the nut 37 slides in the +Z direction when the lead screw 36 rotates in the forward direction, and slides in the -Z direction when the lead screw 36 rotates in the reverse direction.

As the nut 37 slides in the +Z direction, the end portion 715 is pressed by the nut 37 in the +Z direction, the movable link 711 and the fixed link 712 approach each other in the Z direction, and the top plate 31 and the support frame 32 move upward. Realized. As the nut 37 slides in the -Z direction, the end portion 715 is released from the +Z direction pressure, and the weight of the top plate 31 and the subject P placed on the top plate 31 causes the movable link 711 and the movable link 711 to move. The fixed link 712 is separated in the Z direction, and the lowering motion of the top plate 31 and the support frame 32 is realized.

When the bed driving device 34 receives an OFF control signal from the control device 18 , the table 31 and the support frame 32 are driven by gravity according to the weight of the table 31 and the subject P or the like placed on the table 31 . down motion. For example, when the bed driving device 34 is turned off, the driving force axis of the bed driving device 34 moves the nut 37 in the −Z direction due to gravity acting on the table 31 and the subject P placed on the table 31. It rotates in conjunction with the reverse rotation of the lead screw 36 accompanying the slide.

The braking device 38 is a braking device that suppresses rotation of the lead screw 36 according to a control signal from the control device 18 . A braking device 38 is provided, for example, at one end of the lead screw 36 . The braking device 38 is, for example, a brake such as a friction brake and an electric brake. The braking device 38 may be a brake provided inside the bed driving device 34 . Also, the braking device 38 is an example of a braking section.

For example, when the braking device 38 is a friction brake, the braking device 38 has a brake that suppresses the rotation of the lead screw 36 and an operation mechanism that supports the brake so that the brake can approach or move away from the lead screw 36. . The braking device 38 is, for example, on-off controlled by a signal received from the control device 18 . For example, when the braking device 38 receives an ON signal from the control device 18, the braking device 38 is turned ON, the brake element is pressed against the lead screw 36, and the lead screw 36 is fixed. Since the position of the nut 37 is thereby fixed, the height position of the top plate 31 is maintained. For example, when the brake device 38 receives an off signal from the controller 18, the brake device 38 is turned off, the brake shoe is separated from the lead screw 36, and the lead screw 36 is released. As a result, the lifting operation of the tabletop 31 is realized according to the power of the bed driving device 34 and the weight of the tabletop 31 and the subject P or the like placed on the tabletop 31 .

The bed driving device 34 is controlled so as to maintain the height position of the top plate 31 on which the subject P is placed even if the braking device 38 is suddenly turned off due to malfunction or the like. For example, the bed driving device 34 outputs power to maintain the height position of the top plate 31 on which the subject P is placed even when the braking device 38 is on. Therefore, the bed driving device 34 can maintain the height position of the tabletop 31 even when the braking device 38 is switched from on to off.

The elastic body 80 has an end portion 802 fixed to the base 72 , and the other end portion 801 is provided in the +Y direction when viewed from the end portion 802 . Elastic body 80 includes, for example, a helical spring, an air spring, and rubber. When the top plate 31 is at a position lower than the height (contact position H1) at which the end portion 802 contacts the surface (rear surface) of the top plate 31 opposite to the surface on which the subject P is placed, the elastic body 80 elastically deforms and shrinks. When the top plate 31 is lifted in such a state that the elastic body 80 is elastically deformed, the elastic force of the elastic body 80 is obtained in addition to the power output from the bed driving device 34 . In this manner, the elastic body 80 serves as auxiliary power for lifting the top plate 31 from a position lower than the contact position H1. Although not shown, the elastic body 80 may have an end portion 801 fixed to the back surface of the top plate 31 and the other end portion 802 provided in the -Y direction when viewed from the end portion 801 .

The encoder 81 detects the height position of the top plate 31 . Further, the encoder 81 may detect the amount of displacement from the reference height position. Further, the encoder 81 may detect that the height position of the top plate 31 that was stationary has moved by a certain amount or more. The encoder 81 is, for example, a position detector such as a rotary encoder attached to the top plate 31 . The encoder 81 may be attached to the support frame 32, the guide rail 321, etc., and may detect the calibrated value as the height position.

The configuration of the console device 40 will be described with reference to FIG. 1 again. The console device 40 has a memory 41 , a display 42 , an input interface 43 and a processing circuit 50 . Although the console device 40 is described as being separate from the gantry device 10 in the embodiment, the console device 40 or a part of each component of the console device 40 may be included in the gantry device 10 . Also, the bed device 30 may include the console device 40 or a part of each component of the console device 40 .

The memory 41 is implemented by, for example, a RAM (semiconductor memory device such as a flash memory, a hard disk, an optical disc, etc.) The memory 41 stores, for example, detection data, projection data, reconstructed images, CT images, and the like. These data may be stored in an external memory that can be communicated with the X-ray CT apparatus 1 instead of the memory 41 (or in addition to the memory 41). It is controlled by the cloud server by accepting read/write requests, and the memory 41 is an example of a storage unit.

The display 42 displays various information. For example, the display 42 outputs a medical image such as a CT image generated by the processing circuit 50, a GUI for accepting various operations from the user, and the like. For example, the display 42 is a liquid crystal display or a CRT (Cathode Ray Tube) display. Also, the display 42 is an example of a display unit. The display 42 may be of a desktop type, or may be configured by a tablet terminal or the like capable of wireless communication with the main body of the console device 40 .

The input interface 43 receives various input operations from the user, converts the received input operations into electrical signals, and outputs the electrical signals to the processing circuit 50 . For example, the input interface 43 includes acquisition conditions for acquiring projection data, reconstruction conditions for reconstructing CT images, image processing conditions for generating post-processed images from CT images, and weight estimation, which will be described later. It accepts the necessity etc. from the user. For example, the input interface 43 is implemented by a mouse, keyboard, trackball, switch, button, joystick, and the like. Also, the input interface 43 is an example of an input unit. Also, the input interface 43 may be provided in the gantry device 10 and the bed device 30 . Also, the input interface 43 may be composed of a tablet terminal or the like capable of wireless communication with the main body of the console device 40 .

A processing circuit 50 controls the operation of the entire X-ray CT apparatus 1 . The system control function 51, the preprocessing function 52, the reconstruction processing function 53, the image processing function 54, the scan control function 55, and the display control function 56 of the processing circuit 50 are recorded in the memory 41 in the form of programs executable by a computer. there is The processing circuit 50 reads the programs from the memory 41 and executes them to implement functions corresponding to each program. In other words, the processing circuit 50 with each program read has each function shown in the processing circuit 50 of FIG. The processing circuit 50 is implemented by, for example, a processor. Also, the processing circuit 50 is an example of a processing unit.

In FIG. 1, the processing circuit 50 in a single processor includes a system control function 51, a preprocessing function 52, a reconstruction processing function 53, an image processing function 54, a scan control function 55, and a display control function. The processing functions performed at 56 are implemented. However, the processing circuit 50 may be configured by combining a plurality of independent processors, and each function of the processing circuit 50 may be realized by each processor executing a program. 1, the single memory 41 stores the programs corresponding to the processing functions of the processing circuit 50, but a plurality of memories 41 are arranged in a distributed manner so that the processing circuits 50 are individually stored. A configuration in which the corresponding program is read from the memory 41 may be employed.

The system control function 51 controls various functions of the processing circuit 50 based on input operations received from the user via the input interface 43 . Also, the system control function 51 is an example of a system control unit.

A preprocessing function 52 generates data by performing preprocessing such as logarithmic conversion processing, offset correction processing, inter-channel sensitivity correction processing, and beam hardening correction on the detection data output from the DAS 16 . Data before preprocessing (detection data) and data after preprocessing may be collectively referred to as projection data. Also, the preprocessing function 52 is an example of a preprocessing unit.

A reconstruction processing function 53 performs reconstruction processing using a filtered back projection method, an iterative reconstruction method, or the like on the projection data generated by the preprocessing function 52 to generate CT image data. CT image data is sometimes called a reconstructed image. Also, the reconstruction processing function 53 is an example of a reconstruction processing unit.

The image processing function 54 converts the CT image data generated by the reconstruction processing function 53 into tomographic image data and three-dimensional images of arbitrary cross sections by a known method based on the input operation received from the user via the input interface 43. Convert to data. Note that the reconstruction processing function 53 may directly generate the three-dimensional image data. Also, the image processing function 54 is an example of an image processing unit.

The scan control function 55 controls detection data collection processing in the gantry device 10 by instructing the X-ray high-voltage device 14 , the DAS 16 , the bed drive device 34 and the like via the control device 18 . The scan control function 55 controls the operation of each part when taking a positioning image and when performing actual shooting. Also, the scan control function 55 is an example of a scan control unit.

The display control function 56 displays information such as the estimated weight stored in the memory 41 and the memory 181 and the appropriate value of the contrast medium to be administered to the subject P, and information such as a GUI for receiving various operations from the user. 42. Display control function 56 outputs information to memory 41 and memory 181 based on information received via input interface 43 . Also, the display control function 56 is an example of a display control unit.

Here, an example of the processing of the first embodiment executed by the processing circuit 50 will be described with reference to FIGS. 6 and 7. FIG. FIG. 6 is a flow chart showing an example of the processing of the first embodiment executed by the processing circuit 50 of FIG. Blocks with rounded corners such as S105 in the flowchart of FIG. 6 are processing executed by the user, and are not processing contents of the X-ray CT apparatus 1 according to the present embodiment. The order of the processes in the flowchart illustrated in FIG. 6 may be changed as long as the results are not essentially affected, or the processes may be performed in parallel as long as the results are not essentially affected. FIG. 7 is a graph showing an example of changes in the height position of the tabletop 31 along the process of the flowchart shown in FIG.

(Step S101)
Before starting to use the X-ray CT apparatus 1, the processing circuit 182 executes the necessity determination function 182c to determine whether or not the processing from step S102 to step S108 described later is necessary, that is, whether or not the weight of the subject P is designated. judge. If the determination result requires the processing, the process proceeds to step S102. If the determination result indicates that the process is unnecessary, the process proceeds to step S109 after the subject P is placed on the tabletop 31. FIG.

(Step S102)
Processing circuitry 182 turns off brake device 38 via brake control function 182b. After that, the power control function 182a controls the bed driving device 34 to move the tabletop 31 from the initial position H0 to the contact position H1. An example of a change in the height position of the top plate 31 from the initial position H0 to the contact position H1 is a constant speed movement as shown in the graph of FIG. Even after the top plate 31 moves to the contact position H1, the braking control function 182b keeps the braking device 38 off.

(Step S103)
The processing circuitry 182 turns off the bed drive 34 via the power control function 182a. The top plate 31 descends from the contact position H1 due to gravity acting on the top plate 31 . After the top plate 31 is lowered to a height position (top plate weight holding position H2) where the elastic force corresponding to the elastic deformation generated in the elastic body 80 as the top plate 31 is lowered and the gravity due to the weight of the top plate 31 are balanced. ,Stop. An example of a change in the height position of the top plate 31 from the contact position H1 to the top plate weight stop position H2 is as shown in the graph of FIG. It is a movement that accompanies vibration due to the expansion and contraction of the

(Step S104)
The processing circuit 182 outputs the table weight holding position H2 to the memory 181 by the height acquisition function 182d.

(Step S105)
The user places the subject P on the top board 31 . The tabletop 31 is further lowered from the tabletop weight holding position H2 by gravity due to the weight of the subject P. FIG. The tabletop 31 is positioned at a height position (after placement of the subject) at which the elastic force corresponding to the elastic deformation of the elastic body 80 as the tabletop 31 descends and the gravity due to the weight of the tabletop 31 and the subject P are balanced. After descending to the stop position H3), it stops. An example of a change in the height position of the tabletop 31 from the table weight stop position H2 to the post-subject placement stop position H3 is shown in the graph of FIG. It is a movement accompanied by vibration due to expansion and contraction of the elastic body 80 until it stops.

(Step S106)
The processing circuit 182 outputs the stop position H3 after placing the subject to the memory 181 by the height acquisition function 182d. Further, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after placement of the subject from the memory 181, and calculates the displacement amount of the height position from the initial position H0 to the stop position H3 after placement of the subject. do. In this embodiment, the amount of displacement is called the amount of sinking, and the amount of sinking is output to the memory 181 by the height acquisition function 182d.

(Step S107)
The processing circuit 182 outputs the total weight of the accessories placed on the table top 31 to the memory 181 by the accessory weight acquisition function 182e.

Note that the processes of steps S106 and S107 may be processed in parallel, or the order of the processes may be reversed.

(Step S108)
The processing circuit 182 acquires the amount of subduction from the memory 181 by the estimation function 182f. After that, the estimating function 182f outputs the weight value corresponding to the sinking amount in the lookup table stored in the memory 181 to the memory 181 as the weight (estimated weight) of the subject P placed on the top plate 31. . Furthermore, when the weight of the accessory is obtained in step S107, the estimation function 182f performs post-processing to update the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight once stored in the memory 181. Add

FIG. 8 is an example of a lookup table that the estimation function 182f refers to on the memory 181 in step S108. The lookup table associates the sinking amount with the weight value. A different numerical value is entered for each of the sinking amounts a00, a01, a02, and a03. Each of the weight values w00, w01, w02, and w03 may be a different numerical value or partially the same numerical value. The reason is that when the difference in the amount of sinking is small, the weight values are substantially the same.

(Step S109)
Processing circuit 182 turns on bed drive 34 and brake 38 by means of power control function 182a and brake control function 182b. After that, the processing circuit 50 uses the scan control function 55 to execute positioning imaging or main imaging based on imaging conditions set by the user via the input interface 43 .

Between steps S103 and S104 and between steps S105 and S106, there is a possibility that the height position of the top plate 31 will vibrate due to expansion and contraction of the elastic body 80 . As a countermeasure against the vibration, the execution of steps S104 and S106 is suspended for a pre-determined predetermined time, or steps S104 and S106 are performed until the encoder 81 detects that the height position of the top plate 31 becomes constant. You may add a process to suspend the execution of

In step S104, if there is no accessory attached to the top plate 31, the top plate weight holding position H2 is not acquired. This is because the top plate weight holding position H2 is at a constant height when there is no accessory attached to the top plate 31 . On the other hand, if there is an accessory attached to the top plate 31 in step S104, the top plate weight holding position H2 changes according to the weight of the accessory, so it is necessary to acquire the top plate weight holding position H2 each time. . Therefore, the processing in step S104 will be described separately for the case where no accessory is placed on the top plate 31 and the case where the accessory is placed on the top plate 31 in step S104.

First, the process in step S104 when no accessory is placed on the top plate 31 will be described. Unless the top plate 31 is changed, the top plate weight holding position H2 is a height position at which the gravity corresponding to the weight of the top plate 31 and the elastic force generated in the elastic body 80 are balanced, and thus has a constant value. Therefore, by pre-storing the top plate weight holding position H2 in the case where no accessory is placed on the top plate 31 in the memory 181, the processing for obtaining the top plate weight holding position H2 in step S104 can be omitted. good. Furthermore, in step S106, the height acquisition function 182d may read out the table weight holding position H2 from the memory 181 and calculate the sinking amount.

Next, processing when an accessory is placed on the top plate 31 in step S104 will be described. The top plate weight holding position H2 is the height position of the top plate 31 when the gravity corresponding to the weight of the top plate 31 and the weight of the accessory and the elastic force generated in the elastic body 80 are balanced. The holding position H2 varies according to the weight of the accessory. Therefore, in step S104, when an accessory is placed on the top plate 31, a lookup table corresponding to the top plate weight holding position H2 is stored in advance in the memory 181, and the top plate weight holding position H2 is stored in step S106. A suitable lookup table may be selected and referred to.

The first embodiment has been described above. In the X-ray CT apparatus 1 according to the first embodiment, gravity acting on the subject P placed on the top plate 31 causes the top plate 31 to move from the top plate weight holding position H2 to the post-subject placement stop position H3. Control for descending is performed to obtain the sinking amount, which is the amount of displacement of the height position of the table 31 from the table weight holding position H2 to the post-subject placement stop position H3. The estimation function 182f estimates the weight value corresponding to the amount of sinking as the weight of the subject P placed on the table top 31 using a lookup table.

The estimated weight, which is the result of estimating the weight of the subject P, is displayed on the display 42 by the display control function 56 and presented to the user. Imaging conditions such as the dose of , the X-ray dose, and the irradiation method can be set.

Further, the calculation function 182g can calculate the appropriate dose of the contrast medium from the estimated weight, and the display control function 56 can display the appropriate value on the display 42 to present it to the user. Thereby, the user can easily set the contrast agent to be administered to the subject P to an appropriate value.

Further, the cross-sectional shape of the subject P can be estimated from information obtained by combining the estimated weight with the height, age, and sex of the subject P by the shape estimation function 182h. Furthermore, from the cross-sectional shape of the subject P estimated by the shape estimation function 182h, the position correction function 182i can obtain the amount of correction of the height position of the tabletop 31 during positioning image photography and actual photography. As a result, the user can easily adjust the height position of the tabletop 31 when capturing the positioning image and when capturing the main image.

From here, an example of estimating the weight of the subject P by placing the subject P on the top board 31 at the contact position H1 in the present embodiment will be described.

First, steps S101 and S102 are executed to move the top plate 31 to the contact position H1. Here, the user places the subject P on the tabletop 31 . Since the output of the bed driving device 34 is the power to maintain the height position of the table 31 even if the braking device 38 is suddenly turned off due to malfunction or the like, even if the subject P is placed on the table 31, No immediate descent. Next, the power control function 182a gradually lowers the output of the bed driving device 34 until the bed driving device 34 is turned off. After placing the specimen, it descends to the stop position H3.

The amount of displacement of the height position of the top plate 31 from the contact position H1 to the stop position H3 after placing the subject, which is obtained by the above control, is obtained by the height obtaining function 182d. Here, the amount of displacement is set as the amount of sinking, and the estimation function 182f sets the weight value corresponding to the amount of sinking in the lookup table as the estimated weight. The estimated weight includes the weight of the top plate 31 . Therefore, the estimation function 182f updates the estimated weight to the result of subtracting the weight of the tabletop 31 from the estimated weight stored in the memory 181. FIG. Estimation function 182f may apply further post-processing if necessary to subtract the weight of the accessory.

As described above, even if the displacement amount of the height position of the tabletop 31 from the contact position H1 to the post-subject placement stop position H3 is the sinking amount, the subject P placed on the tabletop 31 does not move. Weight can also be estimated.

(Second embodiment)
In this embodiment, the X link 71 to which the power of the bed driving device 34 is transmitted holds the table 31 on which the subject P is placed. is lowered, the power of the bed driving device 34 is increased to control the height position of the top board 31 to be maintained. In this embodiment, the amount of displacement of the height position of the tabletop 31 during the control, the height position immediately before the tabletop 31 descends, the power of the bed driving device 34 after the tabletop 31 descends, the bed An example of estimating the weight of the subject P placed on the tabletop 31 using a lookup table from information on the amount of change in the power of the driving device 34 will be described.

In addition, in the description of the second embodiment, mainly the differences from the first embodiment will be described. Also, the same reference numerals are assigned to the same configurations as those of the first embodiment, and the description thereof may be omitted.

The processing circuit 182 included in the control device 18 of the X-ray CT apparatus 1 according to this embodiment further includes a power acquisition function 182j. Differs from device 18 . Further, the bed device 30 of the X-ray CT apparatus 1 according to this embodiment differs from the bed device 30 of the X-ray CT apparatus 1 according to the first embodiment shown in FIG. 3 in that a sensor 35 is provided.

First, differences between the control device 18 according to the present embodiment and the control device 18 according to the first embodiment will be described. FIG. 9 is a block diagram showing an example of the configuration of the control device 18 according to the second embodiment.

In this embodiment, the memory 181 stores a lookup table different from the lookup table used in the first embodiment. Note that the lookup table will be described later.

A power control function 182a, a braking control function 182b, a necessity determination function 182c, a height acquisition function 182d, an accessory weight acquisition function 182e, an estimation function 182f, a calculation function 182g, a shape estimation function 182h, and a position correction function 182i of the processing circuit 182. , and the power acquisition function 182j are recorded in the memory 181 in the form of a computer-executable program. The power control function 182a, the braking control function 182b, the necessity determination function 182c, the height acquisition function 182d, the accessory weight acquisition function 182e, the calculation function 182g, the shape estimation function 182h, the position correction function 182i, and the has the same function as that of the first embodiment, so the description is omitted. From here, the power acquisition function 182j and the difference between the estimation function 182f in the present embodiment and the estimation function 182f in the first embodiment will be described.

The power acquisition function 182 j estimates the power of the bed driving device 34 from the power information acquired from the sensor 35 and outputs the estimation result to the memory 181 . Sensor 35 and power information will be described later. The power acquisition function 182j can calculate the power by using, for example, a relational expression between power information obtained in advance and the power of the bed driving device 34 . Also, the power acquisition function 182j may output to the memory 181 the amount of change from the reference power. The power acquisition function 182j is an example of a power acquisition unit.

The estimation function 182f estimates the weight of the subject P placed on the tabletop 31 also in this embodiment. The estimation function 182f, for example, calculates the height position of the table top 31, the power of the bed drive device 34, and the power of the bed drive device 34 in addition to the amount of displacement of the height position of the table top 31 stored in the memory 181. The weight (estimated weight) of the subject P placed on the tabletop 31 is output to the memory 181 using a lookup table in which displacement amounts are associated with a plurality of weight values. Also in this embodiment, the estimating function 182f has a function of updating to an estimated weight excluding the weight of accessories, like the estimating function 182f in the first embodiment.

Next, differences between the bed device 30 according to the present embodiment and the bed device 30 according to the first embodiment will be described. FIG. 10 is a block diagram showing an example of the configuration of a bed device 30a according to the second embodiment. A bed device 30 according to the present embodiment includes a sensor 35 in addition to the constituent elements of the bed device 30 according to the first embodiment.

The sensor 35 detects power information necessary for estimating the power of the bed driving device 34 . The power information is, for example, the current that flows through the bed drive device 34 when the bed drive device 34 rotates the lead screw 36 . The sensor 35 is, for example, a current sensor that detects a current value flowing through the bed driving device 34 . The sensor 35 may be included in the configuration of the bed driving device 34 or may be configured as a separate body from the bed driving device 34 .

An example of the processing of the second embodiment executed by the processing circuit 182 and the processing circuit 50 will now be described with reference to FIGS. 11 and 12. FIG. FIG. 11 is a flow chart showing an example of the process of the second embodiment executed by the processing circuit 182 and the processing circuit 50. As shown in FIG. Blocks with rounded corners such as S201 in the flowchart of FIG. 11 are processing executed by the user, and are not processing contents of the X-ray CT apparatus 1 according to the present embodiment. The order of the processes in the flowchart illustrated in FIG. 11 may be changed as long as the results are not essentially affected, or the processes may be performed in parallel as long as the results are not essentially affected. FIG. 12 is a graph showing an example of changes in the height position of the tabletop 31 along the process of the flowchart shown in FIG.

(Step S201)
The user places the subject P on the top board 31 . In step S201, the braking device 38 is on. The height position of the top plate 31 is maintained at the initial position H0. Further, the bed drive device 34 outputs power (initial position holding torque T1) for holding the height position of the tabletop 31 even if the braking device 38 is suddenly turned off due to malfunction or the like.

(Step S202)
The processing circuit 182 executes the necessity determination function 182c to determine whether or not the processing from step S203 to step S211, which will be described later, is necessary, that is, whether or not the weight of the subject P is to be specified. If the determination result indicates that the process is required, the process proceeds to step S203. If the determination result indicates that the process is unnecessary, the process proceeds to step S212.

(Step S203)
The processing circuit 182 executes the height acquisition function 182d and outputs the initial position H0, which is the height position of the tabletop 31, to the memory 181. FIG.

(Step S204)
Processing circuitry 182 turns off brake device 38 via brake control function 182b. Further, the processing circuit 182 causes the bed driving device 34 to maintain the output of the initial position holding torque T1 by the power control function 182a. Therefore, the height position of the top plate 31 is maintained.

(Step S205)
The processing circuit 182 executes the power acquisition function 182j to output the initial position holding torque T1 to the memory 181. FIG.

Note that the processes of steps S203, S204, and S205 may be processed in parallel, or the order of the processes may be changed.

(Step S206)
The processing circuit 182 uses the power control function 182a to cause the bed driving device 34 to maintain the output of the power (lowering start torque T4) that is a fixed value lower than the initial position holding torque T1. Thereby, the top plate 31 descends from the initial position H0. The height position of the top plate 31 drops rapidly as shown in the graph of FIG. An example of the relationship between the initial position holding torque T1 and the descent start torque T4 is shown in the graph of FIG. Also, the lowering start torque T4 is an example of power for lowering the top plate 31 .

(Step S207)
When the top plate 31 reaches a lowering detection position H<b>5 lower than the initial position H<b>0 by a certain value, the encoder 81 detects a change in the height position of the top plate 31 . After that, the power control function 182a increases the output of the bed driving device 34 from the lowering start torque T4 until the tabletop 31 stops.

As an example of how to increase the output of the bed driving device 34 in step S207, as shown in the graph of FIG. The smaller the descending speed of the plate 31, the smaller the increase in the output of the bed driving device 34. When the output of the bed driving device 34 is switched from the descent start torque T4 to the output (output T5) that is larger by a certain value like a step function and maintained, if the output T5 is appropriate, the top plate 31 stops, but the output T5 is excessive, the top plate 31 shifts to an upward motion, and when the output T5 becomes insufficient, the downward motion does not stop. This is due to the characteristic of the X link 71 that the higher the height of the top plate 31, the smaller the power required for holding and lifting, and the lower the height of the top plate 31, the larger the power required for holding and lifting. It is. For the above reasons, it is preferable to increase the output of the bed driving device 34 in accordance with the speed at which the tabletop 31 descends, as described above.

(Step S208)
The processing circuit 182 outputs to the memory 181 the height position of the top plate 31 when the top plate 31 stops descending (post-subject placement stop position H3) using the height acquisition function 182d. Further, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after placement of the subject from the memory 181, and calculates the displacement amount of the height position from the initial position H0 to the stop position H3 after placement of the subject. do. In this embodiment, the amount of displacement is called the amount of sinking, and the amount of sinking is output to the memory 181 by the height acquisition function 182d.

(Step S209)
The processing circuit 182 outputs to the memory 181 the power (stop position holding torque T3) of the bed driving device 34 when the top plate 31 is held at the stop position H3 after the subject is placed, using the power acquisition function 182j. Further, the power acquisition function 182j reads out the initial position holding torque T1 and the stop position holding torque T3 from the memory 181, and calculates the amount of change from the initial position holding torque T1 to the stop position holding torque T3. In this embodiment, the amount of change is called a holding torque change amount, and the holding torque change amount is output to the memory 181 by the power acquisition function 182j.

The stop position holding torque T3 becomes a larger value than the initial position holding torque T1. The reason is that the lower the height position of the top plate 31, the greater the power required for holding and lifting.

Note that the processes of steps S208 and S209 may be processed in parallel, or the order of the processes may be reversed.

(Step S210)
The processing circuit 182 outputs the total weight of the accessories placed on the table top 31 to the memory 181 by the accessory weight acquisition function 182e. Note that step S210 may be processed in parallel with the processing from step S203 to step S209, or the order of processing may be changed.

(Step S211)
The processing circuit 182 acquires the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount from the memory 181 by the estimation function 182f. After that, the estimating function 182f puts weight values corresponding to the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount in the lookup table stored in the memory 181 on the table top 31. The weight (estimated weight) of the subject P is output to the memory 181 . Furthermore, when the weight of the accessory is obtained in step S210, the estimation function 182f once updates the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight stored in the memory 181. Add processing.

FIG. 13 is an example of a lookup table referenced by the estimation function 182f in step S210. In the lookup table, the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount are associated with the weight values. Different numerical values are entered for the sinking amounts a10 and a11. On the other hand, the initial positions h10, h11, the stop position holding torques x10, x11, x12, and the amounts of change in the holding torques y11, y12 may be partially the same or different values. The reason for this is to cover possible combinations of the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount. Further, each of the weight values wa10, wa11, wb10, wb11, wc10, wd10, wd11, wd12, we10, we11, and we12 may be partially the same numerical value or may be a different numerical value. The reason for this is that even if conditions such as the sinking amount, the initial position H0, the stop position holding torque T3, and the amount of change in the holding torque change, the change in the weight value may be substantially the same.

(Step S212)
Processing circuit 182 turns on bed drive 34 and brake 38 by means of power control function 182a and brake control function 182b. After that, the processing circuit 50 uses the scan control function 55 to execute positioning imaging or main imaging based on imaging conditions set by the user via the input interface 43 .

The second embodiment has been described above. According to the second embodiment, as described above, in the X-ray CT apparatus 1 according to the present embodiment, the height position of the top plate 31 when placing the subject P is limited to the contact position H1 or less. control is performed so that the top plate 31 descends from the initial position H0 to the stop position H3 after placement of the subject. Accordingly, the user can acquire the weight of the subject P from the couch device 30 after selecting the height of the table top 31 on which the subject P is placed according to the situation.

(Third Embodiment)
In this embodiment, the subject P is placed on the top plate 31 while the top plate 31 on which the subject P is not placed is held by the X link 71 to which the power of the bed driving device 34 is transmitted. Then, the top plate 31 descends. After that, the power of the bed driving device 34 is increased to hold the top board 31.例文帳に追加The amount of displacement of the height position of the top plate 31 during the above control, the height position immediately before the top plate 31 descends, the power of the bed driving device 34 after the top plate 31 has descended, and the power of the bed driving device 34 An example of estimating the weight of the subject P placed on the table top 31 using a lookup table from information on the amount of change in power will be described. Note that in the description of the third embodiment, mainly the differences from the first and second embodiments will be described. Also, since the configuration of this embodiment is the same as that of the second embodiment, the same reference numerals are used and the description thereof is omitted.

An example of the processing of the third embodiment executed by the processing circuit 182 and the processing circuit 50 will now be described with reference to FIGS. 14 and 15. FIG. FIG. 14 is a flow chart showing an example of the processing of this embodiment executed by the processing circuit 182 and the processing circuit 50. As shown in FIG. Blocks with rounded corners such as S306 in the flowchart of FIG. 14 are processing executed by the user, and are not processing contents of the X-ray CT apparatus 1 according to the present embodiment. The order of the processes in the flowchart illustrated in FIG. 14 may be changed as long as the results are not essentially affected, or the processes may be performed in parallel as long as the results are not essentially affected. FIG. 15 is a graph showing an example of changes in the height position of the tabletop 31 along the process of the flowchart shown in FIG.

(Step S301)
Before starting to use the X-ray CT apparatus 1, the processing circuit 182 executes the necessity determination function 182c to determine whether or not the processing from step S302 to step S311 described later is necessary, that is, whether or not the weight of the subject P is designated. judge. If the determination result indicates that the process is required, the process proceeds to step S302. If the determination result indicates that the process is unnecessary, the process proceeds to step S312 after the subject P is placed on the top plate 31 .

(Step S302)
The processing circuit 182 outputs the height position of the tabletop 31 to the memory 181 as the initial position H0 by the height acquisition function 182d. In step S302, the power of the bed driving device 34 is assumed to be the initial position torque T0.

(Step S303)
Processing circuitry 182 turns off brake device 38 via brake control function 182b.

Note that the processes of steps S302 and S303 may be processed in parallel, or the order of the processes may be reversed.

(Step S304)
The processing circuit 182 uses the power control function 182a to convert the power of the bed driving device 34 from the initial position torque T0 to the power for lowering the table 31 when the subject P is placed on the table (table weight holding torque T2). down to The top plate weight holding torque T2 is an example of power for lowering the top plate 31 .

(Step S305)
The processing circuit 182 outputs the table weight holding torque T2 to the memory 181 by the power acquisition function 182j.

(Step S306)
The user places the subject P on the top board 31 . After that, the top plate 31 descends from the initial position H0.

(Step S307)
When the top plate 31 reaches a downward detection position H5 that is lower than the initial position H0 by a fixed value, the encoder 81 detects a change in the height position of the top plate 31 . After that, the power control function 182a increases the power of the bed driving device 34 from the table weight holding torque T2 until the table 31 stops.

One example of how to increase the output of the bed driving device 34 in step S307 is to increase the amount of increase in the output of the bed driving device 34 as the descending speed of the tabletop 31 increases as shown in the graph of FIG. The smaller the descending speed of the plate 31, the smaller the increase in the output of the bed driving device 34. The reason why it is preferable to increase the output of the bed driving device 34 according to the descending speed of the table top 31 is as described in step S207.

(Step S308)
The processing circuit 182 outputs to the memory 181 the height position of the top plate 31 when the top plate 31 stops descending (post-subject placement stop position H3) using the height acquisition function 182d. Further, the height acquisition function 182d reads out the initial position H0 and the stop position H3 after placement of the subject from the memory 181, and calculates the displacement amount of the height position from the initial position H0 to the stop position H3 after placement of the subject. do. In this embodiment, the amount of displacement is called the amount of sinking, and the amount of sinking is output to the memory 181 by the height acquisition function 182d.

(Step S309)
The processing circuit 182 outputs to the memory 181 the power (stop position holding torque T3) of the bed driving device 34 when the top plate 31 is held at the stop position H3 after the subject is placed, using the power acquisition function 182j. Further, the power acquisition function 182j reads out the table weight holding torque T2 and the stop position holding torque T3 from the memory 181, and calculates the amount of change from the table weight holding torque T2 to the stop position holding torque T3. In this embodiment, the amount of change is called a holding torque change amount, and the holding torque change amount is output to the memory 181 by the power acquisition function 182j.

Note that the processes of steps S308 and S309 may be processed in parallel, or the order of the processes may be reversed.

(Step S310)
The processing circuit 182 outputs the total weight of the accessories placed on the table top 31 to the memory 181 by the accessory weight acquisition function 182e. Note that step S310 may be processed in parallel with the processes from step S307 to step S309, or the order of the processes may be changed.

(Step S311)
The processing circuit 182 acquires the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount from the memory 181 by the estimation function 182f. After that, the estimating function 182f uses the lookup table stored in the memory 181 to obtain the weight values corresponding to the amount of sinking, the initial position H0, the stop position holding torque T3, and the amount of change in the holding torque. The weight (estimated weight) of the subject P is output to the memory 181 . Further, when the weight of the accessory is obtained in step S310, the estimation function 182f once updates the estimated weight to a value obtained by subtracting the total weight of the accessories from the estimated weight stored in the memory 181. Add processing.

An example of the lookup table referred to by the estimation function 182f in S311 is shown in FIG. 13, as in the second embodiment. In the lookup table, the sinking amount, the initial position H0, the stop position holding torque T3, and the holding torque change amount are associated with the estimated weight.

(Step S312)
Processing circuit 182 turns on bed drive 34 and brake 38 by means of power control function 182a and brake control function 182b. After that, the processing circuit 50 uses the scan control function 55 to execute positioning imaging or main imaging based on imaging conditions set by the user via the input interface 43 .

The third embodiment has been described above. According to the third embodiment, as described above, in the X-ray CT apparatus 1 according to the present embodiment, the height position of the top board 31 when placing the subject P is limited to the contact position H1 or less. In addition to controlling the table 31 to descend from the initial position H0 to the stop position H3 after the subject P is placed on the table 31, the necessity of the control and weight estimation is determined before the subject P is placed on the table 31. to accept. As a result, the X-ray CT apparatus 1 according to the present embodiment can reduce the number of steps required for weight estimation after the subject P is placed on the top board 31 . As a result, even in an emergency or the like when it is necessary to obtain the estimated weight of the subject P in a shorter time, the user can use the X-ray CT apparatus 1 to estimate the weight before placing the subject P on the tabletop 31 . By making preparations, it is possible to select shooting including weight estimation.

Note that in the second and third embodiments as well, by executing the display control function 56, the user can adjust the dosage of the contrast agent in the positioning image imaging and the main imaging according to the weight of the subject P. , X-ray dose, and exposure method can be determined. In addition, in the second and third embodiments, the calculation function 182g allows the user to easily set imaging conditions for administering an appropriate amount of contrast agent. Furthermore, in the second embodiment and the third embodiment, the shape estimation function 182h and the position correction function 182i allow the user to easily adjust the height position of the tabletop 31 at the time of capturing the positioning image and the actual capturing. be able to.

(Fourth embodiment)
In the first to third embodiments described above, the example of estimating the weight of the subject P with the medical image diagnostic apparatus has been described. In this embodiment, the couch apparatus alone performs processing corresponding to the weight estimation of the subject P in the medical image diagnostic apparatus according to the first embodiment, and the result of the estimation is sent to the communicably connected medical image diagnostic apparatus. An example of transmission will be described. Note that in the description of this embodiment, differences from the first embodiment will mainly be described. Also, the same reference numerals are assigned to the same configurations as those of the first embodiment, and the description thereof may be omitted.

FIG. 16 is a block diagram showing an example of the configuration of a bed device 30a according to the fourth embodiment. A bed device 30a according to the present embodiment includes the memory 181, the processing circuit 182, the camera 20, the display 42, and the input interface 43 according to the first embodiment in addition to the configuration of the bed device 30 according to the first embodiment. , a processing circuit 183, a camera 20a, a display 42a, and an input interface 43a. Power control function 183a, braking control function 183b, necessity determination function 183c, height acquisition function 183d, accessory weight acquisition function 183e, estimation function 183f, calculation function 183g, shape estimation function 183h, position correction function 183i, display The control function 183j includes the power control function 182a, the braking control function 182b, the necessity determination function 182c, the height acquisition function 182d, the accessory weight acquisition function 182e, the estimation function 182f, the calculation function 182g, and the It corresponds to the shape estimation function 182h, the position correction function 182i, and the display control function 56. FIG. Further, the bed device 30a according to the present embodiment further includes a communication device 90. As shown in FIG.

The communication device 90 performs data communication with devices connected via the network NW. The communication device 90 is a wireless or wired interface for communicating with the outside, and is implemented by, for example, a network card, network adapter, NIC (Network Interface Controller), or the like. Network NW means the entire information communication network using electronic communication technology, and includes Internet networks such as hospital backbone LAN, wireless LAN, and wired LAN, as well as telephone communication network, optical fiber communication network, cable communication network, and Including satellite communication networks. The device is, for example, a medical image diagnostic device, a RIS, and the like. The communication device 90 transmits to the device information generated by each function of the processing circuit 183, such as the estimated weight, the appropriate contrast agent value, and the position correction amount. The communication device 90 receives, for example, a control signal for the bed device 30a during imaging from the medical image diagnostic apparatus. Also, the communication device 90 is an example of a communication unit.

With the configuration described above, the bed device 30a according to the present embodiment also executes the same processing as the flowchart shown in FIG. 6 to obtain the estimated weight. Further, the bed device 30a transmits the estimated weight to the medical image diagnostic apparatus through the communication device 90. FIG.

In the couch device 30a as well, the calculating function 183g calculates the appropriate value of the contrast agent according to the weight of the subject P, and the shape estimating function 183h and the position correcting function 183i determine the position of the tabletop 31 during the positioning image capturing and the actual capturing. Acquisition of the position correction amount of the height position is executed. The couch device 30a can transmit the appropriate value of the contrast medium and the position correction amount to the medical image diagnostic apparatus through the communication device 90 . For these reasons, the user uses the medical image diagnostic apparatus to determine the imaging conditions such as the dose of the contrast medium, the X-ray dose, and the irradiation method for the imaging of the positioning image and the main imaging according to the weight of the subject P. be able to.

Further, the bed device 30a can control the bed device 30a suitable for imaging by receiving the imaging conditions set by the user in the medical image diagnostic device from the medical image diagnostic device via the communication device 90. FIG. This allows the user to use the bed device 30a during photographing.

(Fifth embodiment)
In this embodiment, the bed device 30b alone performs processing equivalent to estimating the weight of the subject P in the medical image diagnostic apparatuses according to the second and third embodiments, and performs medical image diagnosis connected communicably. An example of transmitting the estimation result to the device will be described. In addition, in the description of this embodiment, mainly the differences from the second and third embodiments will be described. Also, the same reference numerals are assigned to the same configurations as those of the second and third embodiments, and description thereof may be omitted.

FIG. 17 is a block diagram showing an example of the configuration of the bed device 30b according to this embodiment. The bed device 30b according to the present embodiment corresponds to the configuration of the bed device 30 according to the second embodiment, and the memory 181, the processing circuit 182, the camera 20, the display 42, and the input interface 43a according to the second embodiment. A memory 181a, a processing circuit 183, a camera 20a, a display 42a, an input interface 43a, and a communication device 90 are further provided. That is, the bed device 30b according to this embodiment includes the sensor 35 and the power acquisition function 183k in addition to the configuration of the bed device 30a. A power acquisition function 183k of the processing circuit 183 corresponds to the power acquisition function 182j according to the second embodiment.

With the configuration described above, the bed device 30b according to the present embodiment can also obtain an estimated weight by executing the same processing as the flowcharts shown in FIGS. 11 and 14 . That is, the bed device 30b can perform processing corresponding to weight estimation of the subject P in the medical image diagnostic apparatuses according to the second and third embodiments. Further, the bed device 30b according to the present embodiment can transmit the estimated weight, the appropriate value of the contrast agent, and the position correction amount to the medical image diagnostic apparatus, like the bed device 30a. For these reasons, the user uses the medical image diagnostic apparatus to determine the imaging conditions such as the dose of the contrast medium, the X-ray dose, and the irradiation method for the imaging of the positioning image and the main imaging according to the weight of the subject P. be able to.

In the couch device 30b, the calculation function 183g calculates the appropriate value of the contrast agent according to the weight of the subject P, and the shape estimation function 183h and the position correction function 183i determine the position of the tabletop 31 during the positioning image capturing and the main capturing. Acquisition of the position correction amount of the height position is executed. The couch device 30a can transmit the appropriate value of the contrast medium and the position correction amount to the medical image diagnostic apparatus through the communication device 90 . For these reasons, the user uses the medical image diagnostic apparatus to determine the imaging conditions such as the dose of the contrast medium, the X-ray dose, and the irradiation method for the imaging of the positioning image and the main imaging according to the weight of the subject P. be able to.

Further, like the bed device 30a, the bed device 30b can receive imaging conditions set by the user in the medical image diagnostic device from the medical image diagnostic device. Therefore, the user can use the bed device 30b when photographing.

According to at least one embodiment described above, the weight of the subject P placed on the tabletop 31 can be obtained using the sinking amount, which is the amount of displacement of the height position of the tabletop 31 . As described above, the X-ray CT apparatus 1, the bed device 30a, and the bed device 30b according to the present embodiment can measure the weight of the subject using the bed device.

While several embodiments have been described, these embodiments are provided 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, changes, and combinations of embodiments can be made without departing from the scope of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, as well as the scope of the invention described in the claims and equivalents thereof.

1 X-ray CT apparatus 30 bed device 30a bed device 30b bed device 31 top board 34 bed drive device 35 sensor 36 lead screw 37 nut 38 braking device 71 X link 80 elastic body 90 communication device 182a power control function 182b braking control function 182c required No determination function 182d Height acquisition function 182e Accessory weight acquisition function 182f Estimation function 182g Calculation function 182h Shape estimation function 182i Position correction function 182j Power acquisition function 183a Power control function 183b Braking control function 183c Necessity determination function 183d Height acquisition function 183e Accessory weight acquisition function 183f Estimation function 183g Calculation function 183h Shape estimation function 183i Position correction function 183k Power acquisition function

Claims (14)

a top plate on which the subject is placed;
a lifting mechanism for lifting and lowering the top plate;
a power unit that applies power to the lifting mechanism to hold or lift the top plate;
a power control unit that controls the power unit so that the top plate descends according to the weight of the subject placed on the top plate;
and an estimating unit that estimates an estimated weight, which is the weight of the subject, based on the amount of displacement of the height position of the tabletop under the control. The estimation unit estimates the estimated weight based on a lookup table in which the displacement amount and the weight value are associated.
The medical image diagnostic apparatus according to claim 1. a base to which an end portion of the lifting mechanism opposite to the end portion connected to the top plate is connected;
an elastic body having one end fixed to either the top plate or the base, and the other end facing the other of the top plate or the base;
Under the control, the amount of displacement is determined by the height position at which the elastic body holds the top plate and the elastic body elastically deformed according to the weight of the subject placed on the top plate. , is the difference from the height position holding the top plate on which the subject is placed,
The medical image diagnostic apparatus according to claim 1 or 2. The medical image diagnostic apparatus according to Claim 1, wherein, under the control, the estimation unit estimates the estimated weight further based on the amount of change in the power for holding the tabletop. 5. The medical image diagnostic apparatus according to claim 4, wherein the estimation unit estimates the estimated weight based on a lookup table in which the amount of displacement, the amount of change in power, and a weight value are associated with each other. The amount of displacement is determined by the height position at which the lifting mechanism holds the top plate before the subject is placed at the start of the control, and the height position at which the subject is placed at the end of the control. It is the difference between the height position where the top plate is held by the lifting mechanism,
The medical image diagnostic apparatus according to claim 4 or 5. The amount of change is the difference between the power for holding the tabletop on which the subject is placed and the power for holding the tabletop on which the subject is placed at the end of the control. is
The medical image diagnostic apparatus according to any one of claims 4 to 6. The amount of change is the difference between the power for holding the top plate under the control and the power for holding the top plate on which the subject is placed at the end of the control,
The medical image diagnostic apparatus according to any one of claims 4 to 6. further comprising an accessory weight acquisition unit that acquires the weight of the accessory placed on the top plate;
The medical image diagnostic apparatus according to any one of claims 1 to 8, wherein the estimation unit updates the estimated weight to a value obtained by subtracting the weight of the accessory from the estimated weight. 10. The medical image diagnostic apparatus according to any one of claims 1 to 9, further comprising a calculator that calculates an appropriate value of contrast agent to be administered to the subject based on the estimated weight. The medical image diagnostic apparatus according to any one of claims 1 to 10, further comprising a shape estimator that estimates the shape of the subject based on the estimated weight. 12. The medical image diagnostic apparatus according to claim 11, further comprising a position correction unit that corrects a height position of said tabletop based on the shape of said subject. a top plate on which the subject is placed;
a lifting mechanism for lifting and lowering the top plate;
a power unit that supplies power for supporting or lifting the top plate to the lifting mechanism;
a power control unit that controls the power unit so that the top plate descends according to the weight of the subject placed on the top plate;
and an estimating unit for estimating an estimated weight, which is the weight of the subject, based on a displacement amount of the height position of the top board as the top board descends according to the weight of the subject. The bed device according to claim 13, further comprising a communication unit that transmits the estimated weight to a device that is communicatively connected.

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